[PATCH v11 07/24] cli: Add Busybox upstream hush.c file
Francis Laniel
francis.laniel at amarulasolutions.com
Tue Nov 7 22:41:04 CET 2023
This commit adds new file cli_hush_2021_upstream.c, it is a copy of Busybox hush
file it was of time to Busybox commit 37460f5da.
Signed-off-by: Francis Laniel <francis.laniel at amarulasolutions.com>
Reviewed-by: Simon Glass <sjg at chromium.org>
---
common/cli_hush_upstream.c | 12162 +++++++++++++++++++++++++++++++++++
1 file changed, 12162 insertions(+)
create mode 100644 common/cli_hush_upstream.c
diff --git a/common/cli_hush_upstream.c b/common/cli_hush_upstream.c
new file mode 100644
index 0000000000..c970d9097e
--- /dev/null
+++ b/common/cli_hush_upstream.c
@@ -0,0 +1,12162 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * A prototype Bourne shell grammar parser.
+ * Intended to follow the original Thompson and Ritchie
+ * "small and simple is beautiful" philosophy, which
+ * incidentally is a good match to today's BusyBox.
+ *
+ * Copyright (C) 2000,2001 Larry Doolittle <larry at doolittle.boa.org>
+ * Copyright (C) 2008,2009 Denys Vlasenko <vda.linux at googlemail.com>
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
+ *
+ * Credits:
+ * The parser routines proper are all original material, first
+ * written Dec 2000 and Jan 2001 by Larry Doolittle. The
+ * execution engine, the builtins, and much of the underlying
+ * support has been adapted from busybox-0.49pre's lash, which is
+ * Copyright (C) 1999-2004 by Erik Andersen <andersen at codepoet.org>
+ * written by Erik Andersen <andersen at codepoet.org>. That, in turn,
+ * is based in part on ladsh.c, by Michael K. Johnson and Erik W.
+ * Troan, which they placed in the public domain. I don't know
+ * how much of the Johnson/Troan code has survived the repeated
+ * rewrites.
+ *
+ * Other credits:
+ * o_addchr derived from similar w_addchar function in glibc-2.2.
+ * parse_redirect, redirect_opt_num, and big chunks of main
+ * and many builtins derived from contributions by Erik Andersen.
+ * Miscellaneous bugfixes from Matt Kraai.
+ *
+ * There are two big (and related) architecture differences between
+ * this parser and the lash parser. One is that this version is
+ * actually designed from the ground up to understand nearly all
+ * of the Bourne grammar. The second, consequential change is that
+ * the parser and input reader have been turned inside out. Now,
+ * the parser is in control, and asks for input as needed. The old
+ * way had the input reader in control, and it asked for parsing to
+ * take place as needed. The new way makes it much easier to properly
+ * handle the recursion implicit in the various substitutions, especially
+ * across continuation lines.
+ *
+ * TODOs:
+ * grep for "TODO" and fix (some of them are easy)
+ * make complex ${var%...} constructs support optional
+ * make here documents optional
+ * special variables (done: PWD, PPID, RANDOM)
+ * follow IFS rules more precisely, including update semantics
+ * tilde expansion
+ * aliases
+ * "command" missing features:
+ * command -p CMD: run CMD using default $PATH
+ * (can use this to override standalone shell as well?)
+ * command BLTIN: disables special-ness (e.g. errors do not abort)
+ * command -V CMD1 CMD2 CMD3 (multiple args) (not in standard)
+ * builtins mandated by standards we don't support:
+ * [un]alias, fc:
+ * fc -l[nr] [BEG] [END]: list range of commands in history
+ * fc [-e EDITOR] [BEG] [END]: edit/rerun range of commands
+ * fc -s [PAT=REP] [CMD]: rerun CMD, replacing PAT with REP
+ *
+ * Bash compat TODO:
+ * redirection of stdout+stderr: &> and >&
+ * reserved words: function select
+ * advanced test: [[ ]]
+ * process substitution: <(list) and >(list)
+ * let EXPR [EXPR...]
+ * Each EXPR is an arithmetic expression (ARITHMETIC EVALUATION)
+ * If the last arg evaluates to 0, let returns 1; 0 otherwise.
+ * NB: let `echo 'a=a + 1'` - error (IOW: multi-word expansion is used)
+ * ((EXPR))
+ * The EXPR is evaluated according to ARITHMETIC EVALUATION.
+ * This is exactly equivalent to let "EXPR".
+ * $[EXPR]: synonym for $((EXPR))
+ * indirect expansion: ${!VAR}
+ * substring op on @: ${@:n:m}
+ *
+ * Won't do:
+ * Some builtins mandated by standards:
+ * newgrp [GRP]: not a builtin in bash but a suid binary
+ * which spawns a new shell with new group ID
+ *
+ * Status of [[ support:
+ * [[ args ]] are CMD_SINGLEWORD_NOGLOB:
+ * v='a b'; [[ $v = 'a b' ]]; echo 0:$?
+ * [[ /bin/n* ]]; echo 0:$?
+ * = is glob match operator, not equality operator: STR = GLOB
+ * == same as =
+ * =~ is regex match operator: STR =~ REGEX
+ * TODO:
+ * quoting needs to be considered (-f is an operator, "-f" and ""-f are not; etc)
+ * in word = GLOB, quoting should be significant on char-by-char basis: a*cd"*"
+ */
+//config:config HUSH
+//config: bool "hush (68 kb)"
+//config: default y
+//config: select SHELL_HUSH
+//config: help
+//config: hush is a small shell. It handles the normal flow control
+//config: constructs such as if/then/elif/else/fi, for/in/do/done, while loops,
+//config: case/esac. Redirections, here documents, $((arithmetic))
+//config: and functions are supported.
+//config:
+//config: It will compile and work on no-mmu systems.
+//config:
+//config: It does not handle select, aliases, tilde expansion,
+//config: &>file and >&file redirection of stdout+stderr.
+//config:
+// This option is visible (has a description) to make it possible to select
+// a "scripted" applet (such as NOLOGIN) but avoid selecting any shells:
+//config:config SHELL_HUSH
+//config: bool "Internal shell for embedded script support"
+//config: default n
+//config:
+//config:# hush options
+//config:# It's only needed to get "nice" menuconfig indenting.
+//config:if SHELL_HUSH || HUSH || SH_IS_HUSH || BASH_IS_HUSH
+//config:
+//config:config HUSH_BASH_COMPAT
+//config: bool "bash-compatible extensions"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_BRACE_EXPANSION
+//config: bool "Brace expansion"
+//config: default y
+//config: depends on HUSH_BASH_COMPAT
+//config: help
+//config: Enable {abc,def} extension.
+//config:
+//config:config HUSH_BASH_SOURCE_CURDIR
+//config: bool "'source' and '.' builtins search current directory after $PATH"
+//config: default n # do not encourage non-standard behavior
+//config: depends on HUSH_BASH_COMPAT
+//config: help
+//config: This is not compliant with standards. Avoid if possible.
+//config:
+//config:config HUSH_LINENO_VAR
+//config: bool "$LINENO variable (bashism)"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_INTERACTIVE
+//config: bool "Interactive mode"
+//config: default y
+//config: depends on SHELL_HUSH
+//config: help
+//config: Enable interactive mode (prompt and command editing).
+//config: Without this, hush simply reads and executes commands
+//config: from stdin just like a shell script from a file.
+//config: No prompt, no PS1/PS2 magic shell variables.
+//config:
+//config:config HUSH_SAVEHISTORY
+//config: bool "Save command history to .hush_history"
+//config: default y
+//config: depends on HUSH_INTERACTIVE && FEATURE_EDITING_SAVEHISTORY
+//config:
+//config:config HUSH_JOB
+//config: bool "Job control"
+//config: default y
+//config: depends on HUSH_INTERACTIVE
+//config: help
+//config: Enable job control: Ctrl-Z backgrounds, Ctrl-C interrupts current
+//config: command (not entire shell), fg/bg builtins work. Without this option,
+//config: "cmd &" still works by simply spawning a process and immediately
+//config: prompting for next command (or executing next command in a script),
+//config: but no separate process group is formed.
+//config:
+//config:config HUSH_TICK
+//config: bool "Support command substitution"
+//config: default y
+//config: depends on SHELL_HUSH
+//config: help
+//config: Enable `command` and $(command).
+//config:
+//config:config HUSH_IF
+//config: bool "Support if/then/elif/else/fi"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_LOOPS
+//config: bool "Support for, while and until loops"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_CASE
+//config: bool "Support case ... esac statement"
+//config: default y
+//config: depends on SHELL_HUSH
+//config: help
+//config: Enable case ... esac statement. +400 bytes.
+//config:
+//config:config HUSH_FUNCTIONS
+//config: bool "Support funcname() { commands; } syntax"
+//config: default y
+//config: depends on SHELL_HUSH
+//config: help
+//config: Enable support for shell functions. +800 bytes.
+//config:
+//config:config HUSH_LOCAL
+//config: bool "local builtin"
+//config: default y
+//config: depends on HUSH_FUNCTIONS
+//config: help
+//config: Enable support for local variables in functions.
+//config:
+//config:config HUSH_RANDOM_SUPPORT
+//config: bool "Pseudorandom generator and $RANDOM variable"
+//config: default y
+//config: depends on SHELL_HUSH
+//config: help
+//config: Enable pseudorandom generator and dynamic variable "$RANDOM".
+//config: Each read of "$RANDOM" will generate a new pseudorandom value.
+//config:
+//config:config HUSH_MODE_X
+//config: bool "Support 'hush -x' option and 'set -x' command"
+//config: default y
+//config: depends on SHELL_HUSH
+//config: help
+//config: This instructs hush to print commands before execution.
+//config: Adds ~300 bytes.
+//config:
+//config:config HUSH_ECHO
+//config: bool "echo builtin"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_PRINTF
+//config: bool "printf builtin"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_TEST
+//config: bool "test builtin"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_HELP
+//config: bool "help builtin"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_EXPORT
+//config: bool "export builtin"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_EXPORT_N
+//config: bool "Support 'export -n' option"
+//config: default y
+//config: depends on HUSH_EXPORT
+//config: help
+//config: export -n unexports variables. It is a bash extension.
+//config:
+//config:config HUSH_READONLY
+//config: bool "readonly builtin"
+//config: default y
+//config: depends on SHELL_HUSH
+//config: help
+//config: Enable support for read-only variables.
+//config:
+//config:config HUSH_KILL
+//config: bool "kill builtin (supports kill %jobspec)"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_WAIT
+//config: bool "wait builtin"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_COMMAND
+//config: bool "command builtin"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_TRAP
+//config: bool "trap builtin"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_TYPE
+//config: bool "type builtin"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_TIMES
+//config: bool "times builtin"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_READ
+//config: bool "read builtin"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_SET
+//config: bool "set builtin"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_UNSET
+//config: bool "unset builtin"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_ULIMIT
+//config: bool "ulimit builtin"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_UMASK
+//config: bool "umask builtin"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_GETOPTS
+//config: bool "getopts builtin"
+//config: default y
+//config: depends on SHELL_HUSH
+//config:
+//config:config HUSH_MEMLEAK
+//config: bool "memleak builtin (debugging)"
+//config: default n
+//config: depends on SHELL_HUSH
+//config:
+//config:endif # hush options
+
+//applet:IF_HUSH(APPLET(hush, BB_DIR_BIN, BB_SUID_DROP))
+// APPLET_ODDNAME:name main location suid_type help
+//applet:IF_SH_IS_HUSH( APPLET_ODDNAME(sh, hush, BB_DIR_BIN, BB_SUID_DROP, hush))
+//applet:IF_BASH_IS_HUSH(APPLET_ODDNAME(bash, hush, BB_DIR_BIN, BB_SUID_DROP, hush))
+
+//kbuild:lib-$(CONFIG_SHELL_HUSH) += hush.o match.o shell_common.o
+//kbuild:lib-$(CONFIG_HUSH_RANDOM_SUPPORT) += random.o
+
+/* -i (interactive) is also accepted,
+ * but does nothing, therefore not shown in help.
+ * NOMMU-specific options are not meant to be used by users,
+ * therefore we don't show them either.
+ */
+//usage:#define hush_trivial_usage
+//usage: "[-enxl] [-c 'SCRIPT' [ARG0 ARGS] | FILE [ARGS] | -s [ARGS]]"
+//usage:#define hush_full_usage "\n\n"
+//usage: "Unix shell interpreter"
+
+#if !(defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__NetBSD__) \
+ || defined(__APPLE__) \
+ )
+# include <malloc.h> /* for malloc_trim */
+#endif
+#include <glob.h>
+/* #include <dmalloc.h> */
+#if ENABLE_HUSH_CASE
+# include <fnmatch.h>
+#endif
+#include <sys/times.h>
+#include <sys/utsname.h> /* for setting $HOSTNAME */
+
+#include "busybox.h" /* for APPLET_IS_NOFORK/NOEXEC */
+#include "unicode.h"
+#include "shell_common.h"
+#include "math.h"
+#include "match.h"
+#if ENABLE_HUSH_RANDOM_SUPPORT
+# include "random.h"
+#else
+# define CLEAR_RANDOM_T(rnd) ((void)0)
+#endif
+#ifndef O_CLOEXEC
+# define O_CLOEXEC 0
+#endif
+#ifndef F_DUPFD_CLOEXEC
+# define F_DUPFD_CLOEXEC F_DUPFD
+#endif
+
+#if ENABLE_FEATURE_SH_EMBEDDED_SCRIPTS && !(ENABLE_ASH || ENABLE_SH_IS_ASH || ENABLE_BASH_IS_ASH)
+# include "embedded_scripts.h"
+#else
+# define NUM_SCRIPTS 0
+#endif
+
+/* So far, all bash compat is controlled by one config option */
+/* Separate defines document which part of code implements what */
+#define BASH_PATTERN_SUBST ENABLE_HUSH_BASH_COMPAT
+#define BASH_SUBSTR ENABLE_HUSH_BASH_COMPAT
+#define BASH_SOURCE ENABLE_HUSH_BASH_COMPAT
+#define BASH_DOLLAR_SQUOTE ENABLE_HUSH_BASH_COMPAT
+#define BASH_HOSTNAME_VAR ENABLE_HUSH_BASH_COMPAT
+#define BASH_EPOCH_VARS ENABLE_HUSH_BASH_COMPAT
+#define BASH_TEST2 (ENABLE_HUSH_BASH_COMPAT && ENABLE_HUSH_TEST)
+#define BASH_READ_D ENABLE_HUSH_BASH_COMPAT
+
+
+/* Build knobs */
+#define LEAK_HUNTING 0
+#define BUILD_AS_NOMMU 0
+/* Enable/disable sanity checks. Ok to enable in production,
+ * only adds a bit of bloat. Set to >1 to get non-production level verbosity.
+ * Keeping 1 for now even in released versions.
+ */
+#define HUSH_DEBUG 1
+/* Slightly bigger (+200 bytes), but faster hush.
+ * So far it only enables a trick with counting SIGCHLDs and forks,
+ * which allows us to do fewer waitpid's.
+ * (we can detect a case where neither forks were done nor SIGCHLDs happened
+ * and therefore waitpid will return the same result as last time)
+ */
+#define ENABLE_HUSH_FAST 0
+/* TODO: implement simplified code for users which do not need ${var%...} ops
+ * So far ${var%...} ops are always enabled:
+ */
+#define ENABLE_HUSH_DOLLAR_OPS 1
+
+
+#if BUILD_AS_NOMMU
+# undef BB_MMU
+# undef USE_FOR_NOMMU
+# undef USE_FOR_MMU
+# define BB_MMU 0
+# define USE_FOR_NOMMU(...) __VA_ARGS__
+# define USE_FOR_MMU(...)
+#endif
+
+#include "NUM_APPLETS.h"
+#if NUM_APPLETS == 1
+/* STANDALONE does not make sense, and won't compile */
+# undef CONFIG_FEATURE_SH_STANDALONE
+# undef ENABLE_FEATURE_SH_STANDALONE
+# undef IF_FEATURE_SH_STANDALONE
+# undef IF_NOT_FEATURE_SH_STANDALONE
+# define ENABLE_FEATURE_SH_STANDALONE 0
+# define IF_FEATURE_SH_STANDALONE(...)
+# define IF_NOT_FEATURE_SH_STANDALONE(...) __VA_ARGS__
+#endif
+
+#if !ENABLE_HUSH_INTERACTIVE
+# undef ENABLE_FEATURE_EDITING
+# define ENABLE_FEATURE_EDITING 0
+# undef ENABLE_FEATURE_EDITING_FANCY_PROMPT
+# define ENABLE_FEATURE_EDITING_FANCY_PROMPT 0
+# undef ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
+# define ENABLE_FEATURE_EDITING_SAVE_ON_EXIT 0
+#endif
+
+/* Do we support ANY keywords? */
+#if ENABLE_HUSH_IF || ENABLE_HUSH_LOOPS || ENABLE_HUSH_CASE
+# define HAS_KEYWORDS 1
+# define IF_HAS_KEYWORDS(...) __VA_ARGS__
+# define IF_HAS_NO_KEYWORDS(...)
+#else
+# define HAS_KEYWORDS 0
+# define IF_HAS_KEYWORDS(...)
+# define IF_HAS_NO_KEYWORDS(...) __VA_ARGS__
+#endif
+
+/* If you comment out one of these below, it will be #defined later
+ * to perform debug printfs to stderr: */
+#define debug_printf(...) do {} while (0)
+/* Finer-grained debug switches */
+#define debug_printf_parse(...) do {} while (0)
+#define debug_printf_heredoc(...) do {} while (0)
+#define debug_print_tree(a, b) do {} while (0)
+#define debug_printf_exec(...) do {} while (0)
+#define debug_printf_env(...) do {} while (0)
+#define debug_printf_jobs(...) do {} while (0)
+#define debug_printf_expand(...) do {} while (0)
+#define debug_printf_varexp(...) do {} while (0)
+#define debug_printf_glob(...) do {} while (0)
+#define debug_printf_redir(...) do {} while (0)
+#define debug_printf_list(...) do {} while (0)
+#define debug_printf_subst(...) do {} while (0)
+#define debug_printf_prompt(...) do {} while (0)
+#define debug_printf_clean(...) do {} while (0)
+
+#define ERR_PTR ((void*)(long)1)
+
+#define JOB_STATUS_FORMAT "[%u] %-22s %.40s\n"
+
+#define _SPECIAL_VARS_STR "_*@$!?#-"
+#define SPECIAL_VARS_STR ("_*@$!?#-" + 1)
+#define NUMERIC_SPECVARS_STR ("_*@$!?#-" + 3)
+#if BASH_PATTERN_SUBST
+/* Support / and // replace ops */
+/* Note that // is stored as \ in "encoded" string representation */
+# define VAR_ENCODED_SUBST_OPS "\\/%#:-=+?"
+# define VAR_SUBST_OPS ("\\/%#:-=+?" + 1)
+# define MINUS_PLUS_EQUAL_QUESTION ("\\/%#:-=+?" + 5)
+#else
+# define VAR_ENCODED_SUBST_OPS "%#:-=+?"
+# define VAR_SUBST_OPS "%#:-=+?"
+# define MINUS_PLUS_EQUAL_QUESTION ("%#:-=+?" + 3)
+#endif
+
+#define SPECIAL_VAR_SYMBOL_STR "\3"
+#define SPECIAL_VAR_SYMBOL 3
+/* The "variable" with name "\1" emits string "\3". Testcase: "echo ^C" */
+#define SPECIAL_VAR_QUOTED_SVS 1
+
+struct variable;
+
+static const char hush_version_str[] ALIGN1 = "HUSH_VERSION="BB_VER;
+
+/* This supports saving pointers malloced in vfork child,
+ * to be freed in the parent.
+ */
+#if !BB_MMU
+typedef struct nommu_save_t {
+ struct variable *old_vars;
+ char **argv;
+ char **argv_from_re_execing;
+} nommu_save_t;
+#endif
+
+enum {
+ RES_NONE = 0,
+#if ENABLE_HUSH_IF
+ RES_IF ,
+ RES_THEN ,
+ RES_ELIF ,
+ RES_ELSE ,
+ RES_FI ,
+#endif
+#if ENABLE_HUSH_LOOPS
+ RES_FOR ,
+ RES_WHILE ,
+ RES_UNTIL ,
+ RES_DO ,
+ RES_DONE ,
+#endif
+#if ENABLE_HUSH_LOOPS || ENABLE_HUSH_CASE
+ RES_IN ,
+#endif
+#if ENABLE_HUSH_CASE
+ RES_CASE ,
+ /* three pseudo-keywords support contrived "case" syntax: */
+ RES_CASE_IN, /* "case ... IN", turns into RES_MATCH when IN is observed */
+ RES_MATCH , /* "word)" */
+ RES_CASE_BODY, /* "this command is inside CASE" */
+ RES_ESAC ,
+#endif
+ RES_XXXX ,
+ RES_SNTX
+};
+
+typedef struct o_string {
+ char *data;
+ int length; /* position where data is appended */
+ int maxlen;
+ int o_expflags;
+ /* At least some part of the string was inside '' or "",
+ * possibly empty one: word"", wo''rd etc. */
+ smallint has_quoted_part;
+ smallint has_empty_slot;
+ smallint ended_in_ifs;
+} o_string;
+enum {
+ EXP_FLAG_SINGLEWORD = 0x80, /* must be 0x80 */
+ EXP_FLAG_GLOB = 0x2,
+ /* Protect newly added chars against globbing
+ * by prepending \ to *, ?, [, \ */
+ EXP_FLAG_ESC_GLOB_CHARS = 0x1,
+};
+/* Used for initialization: o_string foo = NULL_O_STRING; */
+#define NULL_O_STRING { NULL }
+
+#ifndef debug_printf_parse
+static const char *const assignment_flag[] = {
+ "MAYBE_ASSIGNMENT",
+ "DEFINITELY_ASSIGNMENT",
+ "NOT_ASSIGNMENT",
+ "WORD_IS_KEYWORD",
+};
+#endif
+
+/* We almost can use standard FILE api, but we need an ability to move
+ * its fd when redirects coincide with it. No api exists for that
+ * (RFE for it at https://sourceware.org/bugzilla/show_bug.cgi?id=21902).
+ * HFILE is our internal alternative. Only supports reading.
+ * Since we now can, we incorporate linked list of all opened HFILEs
+ * into the struct (used to be a separate mini-list).
+ */
+typedef struct HFILE {
+ char *cur;
+ char *end;
+ struct HFILE *next_hfile;
+ int fd;
+ char buf[1024];
+} HFILE;
+
+typedef struct in_str {
+ const char *p;
+ int peek_buf[2];
+ int last_char;
+ HFILE *file;
+} in_str;
+
+/* The descrip member of this structure is only used to make
+ * debugging output pretty */
+static const struct {
+ int32_t mode;
+ signed char default_fd;
+ char descrip[3];
+} redir_table[] ALIGN4 = {
+ { O_RDONLY, 0, "<" },
+ { O_CREAT|O_TRUNC|O_WRONLY, 1, ">" },
+ { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" },
+ { O_CREAT|O_RDWR, 1, "<>" },
+ { O_RDONLY, 0, "<<" },
+/* Should not be needed. Bogus default_fd helps in debugging */
+/* { O_RDONLY, 77, "<<" }, */
+};
+
+struct redir_struct {
+ struct redir_struct *next;
+ char *rd_filename; /* filename */
+ int rd_fd; /* fd to redirect */
+ /* fd to redirect to, or -3 if rd_fd is to be closed (n>&-) */
+ int rd_dup;
+ smallint rd_type; /* (enum redir_type) */
+ /* note: for heredocs, rd_filename contains heredoc delimiter,
+ * and subsequently heredoc itself; and rd_dup is a bitmask:
+ * bit 0: do we need to trim leading tabs?
+ * bit 1: is heredoc quoted (<<'delim' syntax) ?
+ */
+};
+typedef enum redir_type {
+ REDIRECT_INPUT = 0,
+ REDIRECT_OVERWRITE = 1,
+ REDIRECT_APPEND = 2,
+ REDIRECT_IO = 3,
+ REDIRECT_HEREDOC = 4,
+ REDIRECT_HEREDOC2 = 5, /* REDIRECT_HEREDOC after heredoc is loaded */
+
+ REDIRFD_CLOSE = -3,
+ REDIRFD_SYNTAX_ERR = -2,
+ REDIRFD_TO_FILE = -1,
+ /* otherwise, rd_fd is redirected to rd_dup */
+
+ HEREDOC_SKIPTABS = 1,
+ HEREDOC_QUOTED = 2,
+} redir_type;
+
+
+struct command {
+ pid_t pid; /* 0 if exited */
+ unsigned assignment_cnt; /* how many argv[i] are assignments? */
+#if ENABLE_HUSH_LINENO_VAR
+ unsigned lineno;
+#endif
+ smallint cmd_type; /* CMD_xxx */
+#define CMD_NORMAL 0
+#define CMD_SUBSHELL 1
+#if BASH_TEST2
+/* used for "[[ EXPR ]]" */
+# define CMD_TEST2_SINGLEWORD_NOGLOB 2
+#endif
+#if BASH_TEST2 || ENABLE_HUSH_LOCAL || ENABLE_HUSH_EXPORT || ENABLE_HUSH_READONLY
+/* used to prevent word splitting and globbing in "export v=t*" */
+# define CMD_SINGLEWORD_NOGLOB 3
+#endif
+#if ENABLE_HUSH_FUNCTIONS
+# define CMD_FUNCDEF 4
+#endif
+
+ smalluint cmd_exitcode;
+ /* if non-NULL, this "command" is { list }, ( list ), or a compound statement */
+ struct pipe *group;
+#if !BB_MMU
+ char *group_as_string;
+#endif
+#if ENABLE_HUSH_FUNCTIONS
+ struct function *child_func;
+/* This field is used to prevent a bug here:
+ * while...do f1() {a;}; f1; f1() {b;}; f1; done
+ * When we execute "f1() {a;}" cmd, we create new function and clear
+ * cmd->group, cmd->group_as_string, cmd->argv[0].
+ * When we execute "f1() {b;}", we notice that f1 exists,
+ * and that its "parent cmd" struct is still "alive",
+ * we put those fields back into cmd->xxx
+ * (struct function has ->parent_cmd ptr to facilitate that).
+ * When we loop back, we can execute "f1() {a;}" again and set f1 correctly.
+ * Without this trick, loop would execute a;b;b;b;...
+ * instead of correct sequence a;b;a;b;...
+ * When command is freed, it severs the link
+ * (sets ->child_func->parent_cmd to NULL).
+ */
+#endif
+ char **argv; /* command name and arguments */
+/* argv vector may contain variable references (^Cvar^C, ^C0^C etc)
+ * and on execution these are substituted with their values.
+ * Substitution can make _several_ words out of one argv[n]!
+ * Example: argv[0]=='.^C*^C.' here: echo .$*.
+ * References of the form ^C`cmd arg^C are `cmd arg` substitutions.
+ */
+ struct redir_struct *redirects; /* I/O redirections */
+};
+/* Is there anything in this command at all? */
+#define IS_NULL_CMD(cmd) \
+ (!(cmd)->group && !(cmd)->argv && !(cmd)->redirects)
+
+struct pipe {
+ struct pipe *next;
+ int num_cmds; /* total number of commands in pipe */
+ int alive_cmds; /* number of commands running (not exited) */
+ int stopped_cmds; /* number of commands alive, but stopped */
+#if ENABLE_HUSH_JOB
+ unsigned jobid; /* job number */
+ pid_t pgrp; /* process group ID for the job */
+ char *cmdtext; /* name of job */
+#endif
+ struct command *cmds; /* array of commands in pipe */
+ smallint followup; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */
+ IF_HAS_KEYWORDS(smallint pi_inverted;) /* "! cmd | cmd" */
+ IF_HAS_KEYWORDS(smallint res_word;) /* needed for if, for, while, until... */
+};
+typedef enum pipe_style {
+ PIPE_SEQ = 0,
+ PIPE_AND = 1,
+ PIPE_OR = 2,
+ PIPE_BG = 3,
+} pipe_style;
+/* Is there anything in this pipe at all? */
+#define IS_NULL_PIPE(pi) \
+ ((pi)->num_cmds == 0 IF_HAS_KEYWORDS( && (pi)->res_word == RES_NONE))
+
+/* This holds pointers to the various results of parsing */
+struct parse_context {
+ /* linked list of pipes */
+ struct pipe *list_head;
+ /* last pipe (being constructed right now) */
+ struct pipe *pipe;
+ /* last command in pipe (being constructed right now) */
+ struct command *command;
+ /* last redirect in command->redirects list */
+ struct redir_struct *pending_redirect;
+ o_string word;
+#if !BB_MMU
+ o_string as_string;
+#endif
+ smallint is_assignment; /* 0:maybe, 1:yes, 2:no, 3:keyword */
+#if HAS_KEYWORDS
+ smallint ctx_res_w;
+ smallint ctx_inverted; /* "! cmd | cmd" */
+#if ENABLE_HUSH_CASE
+ smallint ctx_dsemicolon; /* ";;" seen */
+#endif
+ /* bitmask of FLAG_xxx, for figuring out valid reserved words */
+ int old_flag;
+ /* group we are enclosed in:
+ * example: "if pipe1; pipe2; then pipe3; fi"
+ * when we see "if" or "then", we malloc and copy current context,
+ * and make ->stack point to it. then we parse pipeN.
+ * when closing "then" / fi" / whatever is found,
+ * we move list_head into ->stack->command->group,
+ * copy ->stack into current context, and delete ->stack.
+ * (parsing of { list } and ( list ) doesn't use this method)
+ */
+ struct parse_context *stack;
+#endif
+};
+enum {
+ MAYBE_ASSIGNMENT = 0,
+ DEFINITELY_ASSIGNMENT = 1,
+ NOT_ASSIGNMENT = 2,
+ /* Not an assignment, but next word may be: "if v=xyz cmd;" */
+ WORD_IS_KEYWORD = 3,
+};
+
+/* On program start, environ points to initial environment.
+ * putenv adds new pointers into it, unsetenv removes them.
+ * Neither of these (de)allocates the strings.
+ * setenv allocates new strings in malloc space and does putenv,
+ * and thus setenv is unusable (leaky) for shell's purposes */
+#define setenv(...) setenv_is_leaky_dont_use()
+struct variable {
+ struct variable *next;
+ char *varstr; /* points to "name=" portion */
+ int max_len; /* if > 0, name is part of initial env; else name is malloced */
+ uint16_t var_nest_level;
+ smallint flg_export; /* putenv should be done on this var */
+ smallint flg_read_only;
+};
+
+enum {
+ BC_BREAK = 1,
+ BC_CONTINUE = 2,
+};
+
+#if ENABLE_HUSH_FUNCTIONS
+struct function {
+ struct function *next;
+ char *name;
+ struct command *parent_cmd;
+ struct pipe *body;
+# if !BB_MMU
+ char *body_as_string;
+# endif
+};
+#endif
+
+
+/* set -/+o OPT support. (TODO: make it optional)
+ * bash supports the following opts:
+ * allexport off
+ * braceexpand on
+ * emacs on
+ * errexit off
+ * errtrace off
+ * functrace off
+ * hashall on
+ * histexpand off
+ * history on
+ * ignoreeof off
+ * interactive-comments on
+ * keyword off
+ * monitor on
+ * noclobber off
+ * noexec off
+ * noglob off
+ * nolog off
+ * notify off
+ * nounset off
+ * onecmd off
+ * physical off
+ * pipefail off
+ * posix off
+ * privileged off
+ * verbose off
+ * vi off
+ * xtrace off
+ */
+static const char o_opt_strings[] ALIGN1 =
+ "pipefail\0"
+ "noexec\0"
+ "errexit\0"
+#if ENABLE_HUSH_MODE_X
+ "xtrace\0"
+#endif
+ ;
+enum {
+ OPT_O_PIPEFAIL,
+ OPT_O_NOEXEC,
+ OPT_O_ERREXIT,
+#if ENABLE_HUSH_MODE_X
+ OPT_O_XTRACE,
+#endif
+ NUM_OPT_O
+};
+
+/* "Globals" within this file */
+/* Sorted roughly by size (smaller offsets == smaller code) */
+struct globals {
+ /* interactive_fd != 0 means we are an interactive shell.
+ * If we are, then saved_tty_pgrp can also be != 0, meaning
+ * that controlling tty is available. With saved_tty_pgrp == 0,
+ * job control still works, but terminal signals
+ * (^C, ^Z, ^Y, ^\) won't work at all, and background
+ * process groups can only be created with "cmd &".
+ * With saved_tty_pgrp != 0, hush will use tcsetpgrp()
+ * to give tty to the foreground process group,
+ * and will take it back when the group is stopped (^Z)
+ * or killed (^C).
+ */
+#if ENABLE_HUSH_INTERACTIVE
+ /* 'interactive_fd' is a fd# open to ctty, if we have one
+ * _AND_ if we decided to act interactively */
+ int interactive_fd;
+ IF_NOT_FEATURE_EDITING_FANCY_PROMPT(char *PS1;)
+# define G_interactive_fd (G.interactive_fd)
+#else
+# define G_interactive_fd 0
+#endif
+#if ENABLE_FEATURE_EDITING
+ line_input_t *line_input_state;
+#endif
+ pid_t root_pid;
+ pid_t root_ppid;
+ pid_t last_bg_pid;
+#if ENABLE_HUSH_RANDOM_SUPPORT
+ random_t random_gen;
+#endif
+#if ENABLE_HUSH_JOB
+ int run_list_level;
+ unsigned last_jobid;
+ pid_t saved_tty_pgrp;
+ struct pipe *job_list;
+# define G_saved_tty_pgrp (G.saved_tty_pgrp)
+#else
+# define G_saved_tty_pgrp 0
+#endif
+ /* How deeply are we in context where "set -e" is ignored */
+ int errexit_depth;
+ /* "set -e" rules (do we follow them correctly?):
+ * Exit if pipe, list, or compound command exits with a non-zero status.
+ * Shell does not exit if failed command is part of condition in
+ * if/while, part of && or || list except the last command, any command
+ * in a pipe but the last, or if the command's return value is being
+ * inverted with !. If a compound command other than a subshell returns a
+ * non-zero status because a command failed while -e was being ignored, the
+ * shell does not exit. A trap on ERR, if set, is executed before the shell
+ * exits [ERR is a bashism].
+ *
+ * If a compound command or function executes in a context where -e is
+ * ignored, none of the commands executed within are affected by the -e
+ * setting. If a compound command or function sets -e while executing in a
+ * context where -e is ignored, that setting does not have any effect until
+ * the compound command or the command containing the function call completes.
+ */
+
+ char o_opt[NUM_OPT_O];
+#if ENABLE_HUSH_MODE_X
+# define G_x_mode (G.o_opt[OPT_O_XTRACE])
+#else
+# define G_x_mode 0
+#endif
+ char opt_s;
+ char opt_c;
+#if ENABLE_HUSH_INTERACTIVE
+ smallint promptmode; /* 0: PS1, 1: PS2 */
+#endif
+ smallint flag_SIGINT;
+#if ENABLE_HUSH_LOOPS
+ smallint flag_break_continue;
+#endif
+#if ENABLE_HUSH_FUNCTIONS
+ /* 0: outside of a function (or sourced file)
+ * -1: inside of a function, ok to use return builtin
+ * 1: return is invoked, skip all till end of func
+ */
+ smallint flag_return_in_progress;
+# define G_flag_return_in_progress (G.flag_return_in_progress)
+#else
+# define G_flag_return_in_progress 0
+#endif
+ smallint exiting; /* used to prevent EXIT trap recursion */
+ /* These support $? */
+ smalluint last_exitcode;
+ smalluint expand_exitcode;
+ smalluint last_bg_pid_exitcode;
+#if ENABLE_HUSH_SET
+ /* are global_argv and global_argv[1..n] malloced? (note: not [0]) */
+ smalluint global_args_malloced;
+# define G_global_args_malloced (G.global_args_malloced)
+#else
+# define G_global_args_malloced 0
+#endif
+#if ENABLE_HUSH_BASH_COMPAT
+ int dead_job_exitcode; /* for "wait -n" */
+#endif
+ /* how many non-NULL argv's we have. NB: $# + 1 */
+ int global_argc;
+ char **global_argv;
+#if !BB_MMU
+ char *argv0_for_re_execing;
+#endif
+#if ENABLE_HUSH_LOOPS
+ unsigned depth_break_continue;
+ unsigned depth_of_loop;
+#endif
+#if ENABLE_HUSH_GETOPTS
+ unsigned getopt_count;
+#endif
+ const char *ifs;
+ char *ifs_whitespace; /* = G.ifs or malloced */
+ const char *cwd;
+ struct variable *top_var;
+ char **expanded_assignments;
+ struct variable **shadowed_vars_pp;
+ unsigned var_nest_level;
+#if ENABLE_HUSH_FUNCTIONS
+# if ENABLE_HUSH_LOCAL
+ unsigned func_nest_level; /* solely to prevent "local v" in non-functions */
+# endif
+ struct function *top_func;
+#endif
+ /* Signal and trap handling */
+#if ENABLE_HUSH_FAST
+ unsigned count_SIGCHLD;
+ unsigned handled_SIGCHLD;
+ smallint we_have_children;
+#endif
+#if ENABLE_HUSH_LINENO_VAR
+ unsigned parse_lineno;
+ unsigned execute_lineno;
+#endif
+ HFILE *HFILE_list;
+ HFILE *HFILE_stdin;
+ /* Which signals have non-DFL handler (even with no traps set)?
+ * Set at the start to:
+ * (SIGQUIT + maybe SPECIAL_INTERACTIVE_SIGS + maybe SPECIAL_JOBSTOP_SIGS)
+ * SPECIAL_INTERACTIVE_SIGS are cleared after fork.
+ * The rest is cleared right before execv syscalls.
+ * Other than these two times, never modified.
+ */
+ unsigned special_sig_mask;
+#if ENABLE_HUSH_JOB
+ unsigned fatal_sig_mask;
+# define G_fatal_sig_mask (G.fatal_sig_mask)
+#else
+# define G_fatal_sig_mask 0
+#endif
+#if ENABLE_HUSH_TRAP
+ int pre_trap_exitcode;
+# if ENABLE_HUSH_FUNCTIONS
+ int return_exitcode;
+# endif
+ char **traps; /* char *traps[NSIG] */
+# define G_traps G.traps
+#else
+# define G_traps ((char**)NULL)
+#endif
+ sigset_t pending_set;
+#if ENABLE_HUSH_MEMLEAK
+ unsigned long memleak_value;
+#endif
+#if ENABLE_HUSH_MODE_X
+ unsigned x_mode_depth;
+ /* "set -x" output should not be redirectable with subsequent 2>FILE.
+ * We dup fd#2 to x_mode_fd when "set -x" is executed, and use it
+ * for all subsequent output.
+ */
+ int x_mode_fd;
+ o_string x_mode_buf;
+#endif
+#if HUSH_DEBUG >= 2
+ int debug_indent;
+#endif
+ struct sigaction sa;
+ char optstring_buf[sizeof("eixcs")];
+#if BASH_EPOCH_VARS
+ char epoch_buf[sizeof("%llu.nnnnnn") + sizeof(long long)*3];
+#endif
+#if ENABLE_FEATURE_EDITING
+ char user_input_buf[CONFIG_FEATURE_EDITING_MAX_LEN];
+#endif
+};
+#define G (*ptr_to_globals)
+/* Not #defining name to G.name - this quickly gets unwieldy
+ * (too many defines). Also, I actually prefer to see when a variable
+ * is global, thus "G." prefix is a useful hint */
+#define INIT_G() do { \
+ SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
+ /* memset(&G.sa, 0, sizeof(G.sa)); */ \
+ sigfillset(&G.sa.sa_mask); \
+ G.sa.sa_flags = SA_RESTART; \
+} while (0)
+
+
+/* Function prototypes for builtins */
+static int builtin_cd(char **argv) FAST_FUNC;
+#if ENABLE_HUSH_ECHO
+static int builtin_echo(char **argv) FAST_FUNC;
+#endif
+static int builtin_eval(char **argv) FAST_FUNC;
+static int builtin_exec(char **argv) FAST_FUNC;
+static int builtin_exit(char **argv) FAST_FUNC;
+#if ENABLE_HUSH_EXPORT
+static int builtin_export(char **argv) FAST_FUNC;
+#endif
+#if ENABLE_HUSH_READONLY
+static int builtin_readonly(char **argv) FAST_FUNC;
+#endif
+#if ENABLE_HUSH_JOB
+static int builtin_fg_bg(char **argv) FAST_FUNC;
+static int builtin_jobs(char **argv) FAST_FUNC;
+#endif
+#if ENABLE_HUSH_GETOPTS
+static int builtin_getopts(char **argv) FAST_FUNC;
+#endif
+#if ENABLE_HUSH_HELP
+static int builtin_help(char **argv) FAST_FUNC;
+#endif
+#if MAX_HISTORY && ENABLE_FEATURE_EDITING
+static int builtin_history(char **argv) FAST_FUNC;
+#endif
+#if ENABLE_HUSH_LOCAL
+static int builtin_local(char **argv) FAST_FUNC;
+#endif
+#if ENABLE_HUSH_MEMLEAK
+static int builtin_memleak(char **argv) FAST_FUNC;
+#endif
+#if ENABLE_HUSH_PRINTF
+static int builtin_printf(char **argv) FAST_FUNC;
+#endif
+static int builtin_pwd(char **argv) FAST_FUNC;
+#if ENABLE_HUSH_READ
+static int builtin_read(char **argv) FAST_FUNC;
+#endif
+#if ENABLE_HUSH_SET
+static int builtin_set(char **argv) FAST_FUNC;
+#endif
+static int builtin_shift(char **argv) FAST_FUNC;
+static int builtin_source(char **argv) FAST_FUNC;
+#if ENABLE_HUSH_TEST || BASH_TEST2
+static int builtin_test(char **argv) FAST_FUNC;
+#endif
+#if ENABLE_HUSH_TRAP
+static int builtin_trap(char **argv) FAST_FUNC;
+#endif
+#if ENABLE_HUSH_TYPE
+static int builtin_type(char **argv) FAST_FUNC;
+#endif
+#if ENABLE_HUSH_TIMES
+static int builtin_times(char **argv) FAST_FUNC;
+#endif
+static int builtin_true(char **argv) FAST_FUNC;
+#if ENABLE_HUSH_UMASK
+static int builtin_umask(char **argv) FAST_FUNC;
+#endif
+#if ENABLE_HUSH_UNSET
+static int builtin_unset(char **argv) FAST_FUNC;
+#endif
+#if ENABLE_HUSH_KILL
+static int builtin_kill(char **argv) FAST_FUNC;
+#endif
+#if ENABLE_HUSH_WAIT
+static int builtin_wait(char **argv) FAST_FUNC;
+#endif
+#if ENABLE_HUSH_LOOPS
+static int builtin_break(char **argv) FAST_FUNC;
+static int builtin_continue(char **argv) FAST_FUNC;
+#endif
+#if ENABLE_HUSH_FUNCTIONS
+static int builtin_return(char **argv) FAST_FUNC;
+#endif
+
+/* Table of built-in functions. They can be forked or not, depending on
+ * context: within pipes, they fork. As simple commands, they do not.
+ * When used in non-forking context, they can change global variables
+ * in the parent shell process. If forked, of course they cannot.
+ * For example, 'unset foo | whatever' will parse and run, but foo will
+ * still be set at the end. */
+struct built_in_command {
+ const char *b_cmd;
+ int (*b_function)(char **argv) FAST_FUNC;
+#if ENABLE_HUSH_HELP
+ const char *b_descr;
+# define BLTIN(cmd, func, help) { cmd, func, help }
+#else
+# define BLTIN(cmd, func, help) { cmd, func }
+#endif
+};
+
+static const struct built_in_command bltins1[] ALIGN_PTR = {
+ BLTIN("." , builtin_source , "Run commands in file"),
+ BLTIN(":" , builtin_true , NULL),
+#if ENABLE_HUSH_JOB
+ BLTIN("bg" , builtin_fg_bg , "Resume job in background"),
+#endif
+#if ENABLE_HUSH_LOOPS
+ BLTIN("break" , builtin_break , "Exit loop"),
+#endif
+ BLTIN("cd" , builtin_cd , "Change directory"),
+#if ENABLE_HUSH_LOOPS
+ BLTIN("continue" , builtin_continue, "Start new loop iteration"),
+#endif
+ BLTIN("eval" , builtin_eval , "Construct and run shell command"),
+ BLTIN("exec" , builtin_exec , "Execute command, don't return to shell"),
+ BLTIN("exit" , builtin_exit , NULL),
+#if ENABLE_HUSH_EXPORT
+ BLTIN("export" , builtin_export , "Set environment variables"),
+#endif
+#if ENABLE_HUSH_JOB
+ BLTIN("fg" , builtin_fg_bg , "Bring job to foreground"),
+#endif
+#if ENABLE_HUSH_GETOPTS
+ BLTIN("getopts" , builtin_getopts , NULL),
+#endif
+#if ENABLE_HUSH_HELP
+ BLTIN("help" , builtin_help , NULL),
+#endif
+#if MAX_HISTORY && ENABLE_FEATURE_EDITING
+ BLTIN("history" , builtin_history , "Show history"),
+#endif
+#if ENABLE_HUSH_JOB
+ BLTIN("jobs" , builtin_jobs , "List jobs"),
+#endif
+#if ENABLE_HUSH_KILL
+ BLTIN("kill" , builtin_kill , "Send signals to processes"),
+#endif
+#if ENABLE_HUSH_LOCAL
+ BLTIN("local" , builtin_local , "Set local variables"),
+#endif
+#if ENABLE_HUSH_MEMLEAK
+ BLTIN("memleak" , builtin_memleak , NULL),
+#endif
+#if ENABLE_HUSH_READ
+ BLTIN("read" , builtin_read , "Input into variable"),
+#endif
+#if ENABLE_HUSH_READONLY
+ BLTIN("readonly" , builtin_readonly, "Make variables read-only"),
+#endif
+#if ENABLE_HUSH_FUNCTIONS
+ BLTIN("return" , builtin_return , "Return from function"),
+#endif
+#if ENABLE_HUSH_SET
+ BLTIN("set" , builtin_set , "Set positional parameters"),
+#endif
+ BLTIN("shift" , builtin_shift , "Shift positional parameters"),
+#if BASH_SOURCE
+ BLTIN("source" , builtin_source , NULL),
+#endif
+#if ENABLE_HUSH_TIMES
+ BLTIN("times" , builtin_times , NULL),
+#endif
+#if ENABLE_HUSH_TRAP
+ BLTIN("trap" , builtin_trap , "Trap signals"),
+#endif
+ BLTIN("true" , builtin_true , NULL),
+#if ENABLE_HUSH_TYPE
+ BLTIN("type" , builtin_type , "Show command type"),
+#endif
+#if ENABLE_HUSH_ULIMIT
+ BLTIN("ulimit" , shell_builtin_ulimit, "Control resource limits"),
+#endif
+#if ENABLE_HUSH_UMASK
+ BLTIN("umask" , builtin_umask , "Set file creation mask"),
+#endif
+#if ENABLE_HUSH_UNSET
+ BLTIN("unset" , builtin_unset , "Unset variables"),
+#endif
+#if ENABLE_HUSH_WAIT
+ BLTIN("wait" , builtin_wait , "Wait for process to finish"),
+#endif
+};
+/* These builtins won't be used if we are on NOMMU and need to re-exec
+ * (it's cheaper to run an external program in this case):
+ */
+static const struct built_in_command bltins2[] ALIGN_PTR = {
+#if ENABLE_HUSH_TEST
+ BLTIN("[" , builtin_test , NULL),
+#endif
+#if BASH_TEST2
+ BLTIN("[[" , builtin_test , NULL),
+#endif
+#if ENABLE_HUSH_ECHO
+ BLTIN("echo" , builtin_echo , NULL),
+#endif
+#if ENABLE_HUSH_PRINTF
+ BLTIN("printf" , builtin_printf , NULL),
+#endif
+ BLTIN("pwd" , builtin_pwd , NULL),
+#if ENABLE_HUSH_TEST
+ BLTIN("test" , builtin_test , NULL),
+#endif
+};
+
+
+/* Debug printouts.
+ */
+#if HUSH_DEBUG >= 2
+/* prevent disasters with G.debug_indent < 0 */
+# define indent() fdprintf(2, "%*s", (G.debug_indent * 2) & 0xff, "")
+# define debug_enter() (G.debug_indent++)
+# define debug_leave() (G.debug_indent--)
+#else
+# define indent() ((void)0)
+# define debug_enter() ((void)0)
+# define debug_leave() ((void)0)
+#endif
+
+#ifndef debug_printf
+# define debug_printf(...) (indent(), fdprintf(2, __VA_ARGS__))
+#endif
+
+#ifndef debug_printf_parse
+# define debug_printf_parse(...) (indent(), fdprintf(2, __VA_ARGS__))
+#endif
+
+#ifndef debug_printf_heredoc
+# define debug_printf_heredoc(...) (indent(), fdprintf(2, __VA_ARGS__))
+#endif
+
+#ifndef debug_printf_exec
+#define debug_printf_exec(...) (indent(), fdprintf(2, __VA_ARGS__))
+#endif
+
+#ifndef debug_printf_env
+# define debug_printf_env(...) (indent(), fdprintf(2, __VA_ARGS__))
+#endif
+
+#ifndef debug_printf_jobs
+# define debug_printf_jobs(...) (indent(), fdprintf(2, __VA_ARGS__))
+# define DEBUG_JOBS 1
+#else
+# define DEBUG_JOBS 0
+#endif
+
+#ifndef debug_printf_expand
+# define debug_printf_expand(...) (indent(), fdprintf(2, __VA_ARGS__))
+# define DEBUG_EXPAND 1
+#else
+# define DEBUG_EXPAND 0
+#endif
+
+#ifndef debug_printf_varexp
+# define debug_printf_varexp(...) (indent(), fdprintf(2, __VA_ARGS__))
+#endif
+
+#ifndef debug_printf_glob
+# define debug_printf_glob(...) (indent(), fdprintf(2, __VA_ARGS__))
+# define DEBUG_GLOB 1
+#else
+# define DEBUG_GLOB 0
+#endif
+
+#ifndef debug_printf_redir
+# define debug_printf_redir(...) (indent(), fdprintf(2, __VA_ARGS__))
+#endif
+
+#ifndef debug_printf_list
+# define debug_printf_list(...) (indent(), fdprintf(2, __VA_ARGS__))
+#endif
+
+#ifndef debug_printf_subst
+# define debug_printf_subst(...) (indent(), fdprintf(2, __VA_ARGS__))
+#endif
+
+#ifndef debug_printf_prompt
+# define debug_printf_prompt(...) (indent(), fdprintf(2, __VA_ARGS__))
+#endif
+
+#ifndef debug_printf_clean
+# define debug_printf_clean(...) (indent(), fdprintf(2, __VA_ARGS__))
+# define DEBUG_CLEAN 1
+#else
+# define DEBUG_CLEAN 0
+#endif
+
+#if DEBUG_EXPAND
+static void debug_print_strings(const char *prefix, char **vv)
+{
+ indent();
+ fdprintf(2, "%s:\n", prefix);
+ while (*vv)
+ fdprintf(2, " '%s'\n", *vv++);
+}
+#else
+# define debug_print_strings(prefix, vv) ((void)0)
+#endif
+
+
+/* Leak hunting. Use hush_leaktool.sh for post-processing.
+ */
+#if LEAK_HUNTING
+static void *xxmalloc(int lineno, size_t size)
+{
+ void *ptr = xmalloc((size + 0xff) & ~0xff);
+ fdprintf(2, "line %d: malloc %p\n", lineno, ptr);
+ return ptr;
+}
+static void *xxrealloc(int lineno, void *ptr, size_t size)
+{
+ ptr = xrealloc(ptr, (size + 0xff) & ~0xff);
+ fdprintf(2, "line %d: realloc %p\n", lineno, ptr);
+ return ptr;
+}
+static char *xxstrdup(int lineno, const char *str)
+{
+ char *ptr = xstrdup(str);
+ fdprintf(2, "line %d: strdup %p\n", lineno, ptr);
+ return ptr;
+}
+static void xxfree(void *ptr)
+{
+ fdprintf(2, "free %p\n", ptr);
+ free(ptr);
+}
+# define xmalloc(s) xxmalloc(__LINE__, s)
+# define xrealloc(p, s) xxrealloc(__LINE__, p, s)
+# define xstrdup(s) xxstrdup(__LINE__, s)
+# define free(p) xxfree(p)
+#endif
+
+
+/* Syntax and runtime errors. They always abort scripts.
+ * In interactive use they usually discard unparsed and/or unexecuted commands
+ * and return to the prompt.
+ * HUSH_DEBUG >= 2 prints line number in this file where it was detected.
+ */
+#if HUSH_DEBUG < 2
+# define msg_and_die_if_script(lineno, ...) msg_and_die_if_script(__VA_ARGS__)
+# define syntax_error(lineno, msg) syntax_error(msg)
+# define syntax_error_at(lineno, msg) syntax_error_at(msg)
+# define syntax_error_unterm_ch(lineno, ch) syntax_error_unterm_ch(ch)
+# define syntax_error_unterm_str(lineno, s) syntax_error_unterm_str(s)
+# define syntax_error_unexpected_ch(lineno, ch) syntax_error_unexpected_ch(ch)
+#endif
+
+static void die_if_script(void)
+{
+ if (!G_interactive_fd) {
+ if (G.last_exitcode) /* sometines it's 2, not 1 (bash compat) */
+ xfunc_error_retval = G.last_exitcode;
+ xfunc_die();
+ }
+}
+
+static void msg_and_die_if_script(unsigned lineno, const char *fmt, ...)
+{
+ va_list p;
+
+#if HUSH_DEBUG >= 2
+ bb_error_msg("hush.c:%u", lineno);
+#endif
+ va_start(p, fmt);
+ bb_verror_msg(fmt, p, NULL);
+ va_end(p);
+ die_if_script();
+}
+
+static void syntax_error(unsigned lineno UNUSED_PARAM, const char *msg)
+{
+ if (msg)
+ bb_error_msg("syntax error: %s", msg);
+ else
+ bb_simple_error_msg("syntax error");
+ die_if_script();
+}
+
+static void syntax_error_at(unsigned lineno UNUSED_PARAM, const char *msg)
+{
+ bb_error_msg("syntax error at '%s'", msg);
+ die_if_script();
+}
+
+static void syntax_error_unterm_str(unsigned lineno UNUSED_PARAM, const char *s)
+{
+ bb_error_msg("syntax error: unterminated %s", s);
+//? source4.tests fails: in bash, echo ${^} in script does not terminate the script
+// die_if_script();
+}
+
+static void syntax_error_unterm_ch(unsigned lineno, char ch)
+{
+ char msg[2] = { ch, '\0' };
+ syntax_error_unterm_str(lineno, msg);
+}
+
+static void syntax_error_unexpected_ch(unsigned lineno UNUSED_PARAM, int ch)
+{
+ char msg[2];
+ msg[0] = ch;
+ msg[1] = '\0';
+#if HUSH_DEBUG >= 2
+ bb_error_msg("hush.c:%u", lineno);
+#endif
+ bb_error_msg("syntax error: unexpected %s", ch == EOF ? "EOF" : msg);
+ die_if_script();
+}
+
+#if HUSH_DEBUG < 2
+# undef msg_and_die_if_script
+# undef syntax_error
+# undef syntax_error_at
+# undef syntax_error_unterm_ch
+# undef syntax_error_unterm_str
+# undef syntax_error_unexpected_ch
+#else
+# define msg_and_die_if_script(...) msg_and_die_if_script(__LINE__, __VA_ARGS__)
+# define syntax_error(msg) syntax_error(__LINE__, msg)
+# define syntax_error_at(msg) syntax_error_at(__LINE__, msg)
+# define syntax_error_unterm_ch(ch) syntax_error_unterm_ch(__LINE__, ch)
+# define syntax_error_unterm_str(s) syntax_error_unterm_str(__LINE__, s)
+# define syntax_error_unexpected_ch(ch) syntax_error_unexpected_ch(__LINE__, ch)
+#endif
+
+
+/* Utility functions
+ */
+/* Replace each \x with x in place, return ptr past NUL. */
+static char *unbackslash(char *src)
+{
+ char *dst = src = strchrnul(src, '\\');
+ while (1) {
+ if (*src == '\\') {
+ src++;
+ if (*src != '\0') {
+ /* \x -> x */
+ *dst++ = *src++;
+ continue;
+ }
+ /* else: "\<nul>". Do not delete this backslash.
+ * Testcase: eval 'echo ok\'
+ */
+ *dst++ = '\\';
+ /* fallthrough */
+ }
+ if ((*dst++ = *src++) == '\0')
+ break;
+ }
+ return dst;
+}
+
+static char **add_strings_to_strings(char **strings, char **add, int need_to_dup)
+{
+ int i;
+ unsigned count1;
+ unsigned count2;
+ char **v;
+
+ v = strings;
+ count1 = 0;
+ if (v) {
+ while (*v) {
+ count1++;
+ v++;
+ }
+ }
+ count2 = 0;
+ v = add;
+ while (*v) {
+ count2++;
+ v++;
+ }
+ v = xrealloc(strings, (count1 + count2 + 1) * sizeof(char*));
+ v[count1 + count2] = NULL;
+ i = count2;
+ while (--i >= 0)
+ v[count1 + i] = (need_to_dup ? xstrdup(add[i]) : add[i]);
+ return v;
+}
+#if LEAK_HUNTING
+static char **xx_add_strings_to_strings(int lineno, char **strings, char **add, int need_to_dup)
+{
+ char **ptr = add_strings_to_strings(strings, add, need_to_dup);
+ fdprintf(2, "line %d: add_strings_to_strings %p\n", lineno, ptr);
+ return ptr;
+}
+#define add_strings_to_strings(strings, add, need_to_dup) \
+ xx_add_strings_to_strings(__LINE__, strings, add, need_to_dup)
+#endif
+
+/* Note: takes ownership of "add" ptr (it is not strdup'ed) */
+static char **add_string_to_strings(char **strings, char *add)
+{
+ char *v[2];
+ v[0] = add;
+ v[1] = NULL;
+ return add_strings_to_strings(strings, v, /*dup:*/ 0);
+}
+#if LEAK_HUNTING
+static char **xx_add_string_to_strings(int lineno, char **strings, char *add)
+{
+ char **ptr = add_string_to_strings(strings, add);
+ fdprintf(2, "line %d: add_string_to_strings %p\n", lineno, ptr);
+ return ptr;
+}
+#define add_string_to_strings(strings, add) \
+ xx_add_string_to_strings(__LINE__, strings, add)
+#endif
+
+static void free_strings(char **strings)
+{
+ char **v;
+
+ if (!strings)
+ return;
+ v = strings;
+ while (*v) {
+ free(*v);
+ v++;
+ }
+ free(strings);
+}
+
+static int dup_CLOEXEC(int fd, int avoid_fd)
+{
+ int newfd;
+ repeat:
+ newfd = fcntl(fd, F_DUPFD_CLOEXEC, avoid_fd + 1);
+ if (newfd >= 0) {
+ if (F_DUPFD_CLOEXEC == F_DUPFD) /* if old libc (w/o F_DUPFD_CLOEXEC) */
+ fcntl(newfd, F_SETFD, FD_CLOEXEC);
+ } else { /* newfd < 0 */
+ if (errno == EBUSY)
+ goto repeat;
+ if (errno == EINTR)
+ goto repeat;
+ }
+ return newfd;
+}
+
+static int xdup_CLOEXEC_and_close(int fd, int avoid_fd)
+{
+ int newfd;
+ repeat:
+ newfd = fcntl(fd, F_DUPFD_CLOEXEC, avoid_fd + 1);
+ if (newfd < 0) {
+ if (errno == EBUSY)
+ goto repeat;
+ if (errno == EINTR)
+ goto repeat;
+ /* fd was not open? */
+ if (errno == EBADF)
+ return fd;
+ xfunc_die();
+ }
+ if (F_DUPFD_CLOEXEC == F_DUPFD) /* if old libc (w/o F_DUPFD_CLOEXEC) */
+ fcntl(newfd, F_SETFD, FD_CLOEXEC);
+ close(fd);
+ return newfd;
+}
+
+
+/* Manipulating HFILEs */
+static HFILE *hfopen(const char *name)
+{
+ HFILE *fp;
+ int fd;
+
+ fd = STDIN_FILENO;
+ if (name) {
+ fd = open(name, O_RDONLY | O_CLOEXEC);
+ if (fd < 0)
+ return NULL;
+ if (O_CLOEXEC == 0) /* ancient libc */
+ close_on_exec_on(fd);
+ }
+
+ fp = xmalloc(sizeof(*fp));
+ if (name == NULL)
+ G.HFILE_stdin = fp;
+ fp->fd = fd;
+ fp->cur = fp->end = fp->buf;
+ fp->next_hfile = G.HFILE_list;
+ G.HFILE_list = fp;
+ return fp;
+}
+static void hfclose(HFILE *fp)
+{
+ HFILE **pp = &G.HFILE_list;
+ while (*pp) {
+ HFILE *cur = *pp;
+ if (cur == fp) {
+ *pp = cur->next_hfile;
+ break;
+ }
+ pp = &cur->next_hfile;
+ }
+ if (fp->fd >= 0)
+ close(fp->fd);
+ free(fp);
+}
+static int refill_HFILE_and_getc(HFILE *fp)
+{
+ int n;
+
+ if (fp->fd < 0) {
+ /* Already saw EOF */
+ return EOF;
+ }
+#if ENABLE_HUSH_INTERACTIVE && !ENABLE_FEATURE_EDITING
+ /* If user presses ^C, read() restarts after SIGINT (we use SA_RESTART).
+ * IOW: ^C will not immediately stop line input.
+ * But poll() is different: it does NOT restart after signals.
+ */
+ if (fp == G.HFILE_stdin) {
+ struct pollfd pfd[1];
+ pfd[0].fd = fp->fd;
+ pfd[0].events = POLLIN;
+ n = poll(pfd, 1, -1);
+ if (n < 0
+ /*&& errno == EINTR - assumed true */
+ && sigismember(&G.pending_set, SIGINT)
+ ) {
+ return '\0';
+ }
+ }
+#else
+/* if FEATURE_EDITING=y, we do not use this routine for interactive input */
+#endif
+ /* Try to buffer more input */
+ n = safe_read(fp->fd, fp->buf, sizeof(fp->buf));
+ if (n < 0) {
+ bb_simple_perror_msg("read error");
+ n = 0;
+ }
+ fp->cur = fp->buf;
+ fp->end = fp->buf + n;
+ if (n == 0) {
+ /* EOF/error */
+ close(fp->fd);
+ fp->fd = -1;
+ return EOF;
+ }
+ return (unsigned char)(*fp->cur++);
+}
+/* Inlined for common case of non-empty buffer.
+ */
+static ALWAYS_INLINE int hfgetc(HFILE *fp)
+{
+ if (fp->cur < fp->end)
+ return (unsigned char)(*fp->cur++);
+ /* Buffer empty */
+ return refill_HFILE_and_getc(fp);
+}
+static int move_HFILEs_on_redirect(int fd, int avoid_fd)
+{
+ HFILE *fl = G.HFILE_list;
+ while (fl) {
+ if (fd == fl->fd) {
+ /* We use it only on script files, they are all CLOEXEC */
+ fl->fd = xdup_CLOEXEC_and_close(fd, avoid_fd);
+ debug_printf_redir("redirect_fd %d: matches a script fd, moving it to %d\n", fd, fl->fd);
+ return 1; /* "found and moved" */
+ }
+ fl = fl->next_hfile;
+ }
+#if ENABLE_HUSH_MODE_X
+ if (G.x_mode_fd > 0 && fd == G.x_mode_fd) {
+ G.x_mode_fd = xdup_CLOEXEC_and_close(fd, avoid_fd);
+ return 1; /* "found and moved" */
+ }
+#endif
+ return 0; /* "not in the list" */
+}
+#if ENABLE_FEATURE_SH_STANDALONE && BB_MMU
+static void close_all_HFILE_list(void)
+{
+ HFILE *fl = G.HFILE_list;
+ while (fl) {
+ /* hfclose would also free HFILE object.
+ * It is disastrous if we share memory with a vforked parent.
+ * I'm not sure we never come here after vfork.
+ * Therefore just close fd, nothing more.
+ *
+ * ">" instead of ">=": we don't close fd#0,
+ * interactive shell uses hfopen(NULL) as stdin input
+ * which has fl->fd == 0, but fd#0 gets redirected in pipes.
+ * If we'd close it here, then e.g. interactive "set | sort"
+ * with NOFORKed sort, would have sort's input fd closed.
+ */
+ if (fl->fd > 0)
+ /*hfclose(fl); - unsafe */
+ close(fl->fd);
+ fl = fl->next_hfile;
+ }
+}
+#endif
+static int fd_in_HFILEs(int fd)
+{
+ HFILE *fl = G.HFILE_list;
+ while (fl) {
+ if (fl->fd == fd)
+ return 1;
+ fl = fl->next_hfile;
+ }
+ return 0;
+}
+
+
+/* Helpers for setting new $n and restoring them back
+ */
+typedef struct save_arg_t {
+ char *sv_argv0;
+ char **sv_g_argv;
+ int sv_g_argc;
+ IF_HUSH_SET(smallint sv_g_malloced;)
+} save_arg_t;
+
+static void save_and_replace_G_args(save_arg_t *sv, char **argv)
+{
+ sv->sv_argv0 = argv[0];
+ sv->sv_g_argv = G.global_argv;
+ sv->sv_g_argc = G.global_argc;
+ IF_HUSH_SET(sv->sv_g_malloced = G.global_args_malloced;)
+
+ argv[0] = G.global_argv[0]; /* retain $0 */
+ G.global_argv = argv;
+ IF_HUSH_SET(G.global_args_malloced = 0;)
+
+ G.global_argc = 1 + string_array_len(argv + 1);
+}
+
+static void restore_G_args(save_arg_t *sv, char **argv)
+{
+#if ENABLE_HUSH_SET
+ if (G.global_args_malloced) {
+ /* someone ran "set -- arg1 arg2 ...", undo */
+ char **pp = G.global_argv;
+ while (*++pp) /* note: does not free $0 */
+ free(*pp);
+ free(G.global_argv);
+ }
+#endif
+ argv[0] = sv->sv_argv0;
+ G.global_argv = sv->sv_g_argv;
+ G.global_argc = sv->sv_g_argc;
+ IF_HUSH_SET(G.global_args_malloced = sv->sv_g_malloced;)
+}
+
+
+/* Basic theory of signal handling in shell
+ * ========================================
+ * This does not describe what hush does, rather, it is current understanding
+ * what it _should_ do. If it doesn't, it's a bug.
+ * http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#trap
+ *
+ * Signals are handled only after each pipe ("cmd | cmd | cmd" thing)
+ * is finished or backgrounded. It is the same in interactive and
+ * non-interactive shells, and is the same regardless of whether
+ * a user trap handler is installed or a shell special one is in effect.
+ * ^C or ^Z from keyboard seems to execute "at once" because it usually
+ * backgrounds (i.e. stops) or kills all members of currently running
+ * pipe.
+ *
+ * Wait builtin is interruptible by signals for which user trap is set
+ * or by SIGINT in interactive shell.
+ *
+ * Trap handlers will execute even within trap handlers. (right?)
+ *
+ * User trap handlers are forgotten when subshell ("(cmd)") is entered,
+ * except for handlers set to '' (empty string).
+ *
+ * If job control is off, backgrounded commands ("cmd &")
+ * have SIGINT, SIGQUIT set to SIG_IGN.
+ *
+ * Commands which are run in command substitution ("`cmd`")
+ * have SIGTTIN, SIGTTOU, SIGTSTP set to SIG_IGN.
+ *
+ * Ordinary commands have signals set to SIG_IGN/DFL as inherited
+ * by the shell from its parent.
+ *
+ * Signals which differ from SIG_DFL action
+ * (note: child (i.e., [v]forked) shell is not an interactive shell):
+ *
+ * SIGQUIT: ignore
+ * SIGTERM (interactive): ignore
+ * SIGHUP (interactive):
+ * send SIGCONT to stopped jobs, send SIGHUP to all jobs and exit
+ * SIGTTIN, SIGTTOU, SIGTSTP (if job control is on): ignore
+ * Note that ^Z is handled not by trapping SIGTSTP, but by seeing
+ * that all pipe members are stopped. Try this in bash:
+ * while :; do :; done - ^Z does not background it
+ * (while :; do :; done) - ^Z backgrounds it
+ * SIGINT (interactive): wait for last pipe, ignore the rest
+ * of the command line, show prompt. NB: ^C does not send SIGINT
+ * to interactive shell while shell is waiting for a pipe,
+ * since shell is bg'ed (is not in foreground process group).
+ * Example 1: this waits 5 sec, but does not execute ls:
+ * "echo $$; sleep 5; ls -l" + "kill -INT <pid>"
+ * Example 2: this does not wait and does not execute ls:
+ * "echo $$; sleep 5 & wait; ls -l" + "kill -INT <pid>"
+ * Example 3: this does not wait 5 sec, but executes ls:
+ * "sleep 5; ls -l" + press ^C
+ * Example 4: this does not wait and does not execute ls:
+ * "sleep 5 & wait; ls -l" + press ^C
+ *
+ * (What happens to signals which are IGN on shell start?)
+ * (What happens with signal mask on shell start?)
+ *
+ * Old implementation
+ * ==================
+ * We use in-kernel pending signal mask to determine which signals were sent.
+ * We block all signals which we don't want to take action immediately,
+ * i.e. we block all signals which need to have special handling as described
+ * above, and all signals which have traps set.
+ * After each pipe execution, we extract any pending signals via sigtimedwait()
+ * and act on them.
+ *
+ * unsigned special_sig_mask: a mask of such "special" signals
+ * sigset_t blocked_set: current blocked signal set
+ *
+ * "trap - SIGxxx":
+ * clear bit in blocked_set unless it is also in special_sig_mask
+ * "trap 'cmd' SIGxxx":
+ * set bit in blocked_set (even if 'cmd' is '')
+ * after [v]fork, if we plan to be a shell:
+ * unblock signals with special interactive handling
+ * (child shell is not interactive),
+ * unset all traps except '' (note: regardless of child shell's type - {}, (), etc)
+ * after [v]fork, if we plan to exec:
+ * POSIX says fork clears pending signal mask in child - no need to clear it.
+ * Restore blocked signal set to one inherited by shell just prior to exec.
+ *
+ * Note: as a result, we do not use signal handlers much. The only uses
+ * are to count SIGCHLDs
+ * and to restore tty pgrp on signal-induced exit.
+ *
+ * Note 2 (compat):
+ * Standard says "When a subshell is entered, traps that are not being ignored
+ * are set to the default actions". bash interprets it so that traps which
+ * are set to '' (ignore) are NOT reset to defaults. We do the same.
+ *
+ * Problem: the above approach makes it unwieldy to catch signals while
+ * we are in read builtin, or while we read commands from stdin:
+ * masked signals are not visible!
+ *
+ * New implementation
+ * ==================
+ * We record each signal we are interested in by installing signal handler
+ * for them - a bit like emulating kernel pending signal mask in userspace.
+ * We are interested in: signals which need to have special handling
+ * as described above, and all signals which have traps set.
+ * Signals are recorded in pending_set.
+ * After each pipe execution, we extract any pending signals
+ * and act on them.
+ *
+ * unsigned special_sig_mask: a mask of shell-special signals.
+ * unsigned fatal_sig_mask: a mask of signals on which we restore tty pgrp.
+ * char *traps[sig] if trap for sig is set (even if it's '').
+ * sigset_t pending_set: set of sigs we received.
+ *
+ * "trap - SIGxxx":
+ * if sig is in special_sig_mask, set handler back to:
+ * record_pending_signo, or to IGN if it's a tty stop signal
+ * if sig is in fatal_sig_mask, set handler back to sigexit.
+ * else: set handler back to SIG_DFL
+ * "trap 'cmd' SIGxxx":
+ * set handler to record_pending_signo.
+ * "trap '' SIGxxx":
+ * set handler to SIG_IGN.
+ * after [v]fork, if we plan to be a shell:
+ * set signals with special interactive handling to SIG_DFL
+ * (because child shell is not interactive),
+ * unset all traps except '' (note: regardless of child shell's type - {}, (), etc)
+ * after [v]fork, if we plan to exec:
+ * POSIX says fork clears pending signal mask in child - no need to clear it.
+ *
+ * To make wait builtin interruptible, we handle SIGCHLD as special signal,
+ * otherwise (if we leave it SIG_DFL) sigsuspend in wait builtin will not wake up on it.
+ *
+ * Note (compat):
+ * Standard says "When a subshell is entered, traps that are not being ignored
+ * are set to the default actions". bash interprets it so that traps which
+ * are set to '' (ignore) are NOT reset to defaults. We do the same.
+ */
+enum {
+ SPECIAL_INTERACTIVE_SIGS = 0
+ | (1 << SIGTERM)
+ | (1 << SIGINT)
+ | (1 << SIGHUP)
+ ,
+ SPECIAL_JOBSTOP_SIGS = 0
+#if ENABLE_HUSH_JOB
+ | (1 << SIGTTIN)
+ | (1 << SIGTTOU)
+ | (1 << SIGTSTP)
+#endif
+ ,
+};
+
+static void record_pending_signo(int sig)
+{
+ sigaddset(&G.pending_set, sig);
+#if ENABLE_HUSH_FAST
+ if (sig == SIGCHLD) {
+ G.count_SIGCHLD++;
+//bb_error_msg("[%d] SIGCHLD_handler: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
+ }
+#endif
+}
+
+static sighandler_t install_sighandler(int sig, sighandler_t handler)
+{
+ struct sigaction old_sa;
+
+ /* We could use signal() to install handlers... almost:
+ * except that we need to mask ALL signals while handlers run.
+ * I saw signal nesting in strace, race window isn't small.
+ * SA_RESTART is also needed, but in Linux, signal()
+ * sets SA_RESTART too.
+ */
+ /* memset(&G.sa, 0, sizeof(G.sa)); - already done */
+ /* sigfillset(&G.sa.sa_mask); - already done */
+ /* G.sa.sa_flags = SA_RESTART; - already done */
+ G.sa.sa_handler = handler;
+ sigaction(sig, &G.sa, &old_sa);
+ return old_sa.sa_handler;
+}
+
+static void hush_exit(int exitcode) NORETURN;
+
+static void restore_ttypgrp_and__exit(void) NORETURN;
+static void restore_ttypgrp_and__exit(void)
+{
+ /* xfunc has failed! die die die */
+ /* no EXIT traps, this is an escape hatch! */
+ G.exiting = 1;
+ hush_exit(xfunc_error_retval);
+}
+
+#if ENABLE_HUSH_JOB
+
+/* Needed only on some libc:
+ * It was observed that on exit(), fgetc'ed buffered data
+ * gets "unwound" via lseek(fd, -NUM, SEEK_CUR).
+ * With the net effect that even after fork(), not vfork(),
+ * exit() in NOEXECed applet in "sh SCRIPT":
+ * noexec_applet_here
+ * echo END_OF_SCRIPT
+ * lseeks fd in input FILE object from EOF to "e" in "echo END_OF_SCRIPT".
+ * This makes "echo END_OF_SCRIPT" executed twice.
+ * Similar problems can be seen with msg_and_die_if_script() -> xfunc_die()
+ * and in `cmd` handling.
+ * If set as die_func(), this makes xfunc_die() exit via _exit(), not exit():
+ */
+static void fflush_and__exit(void) NORETURN;
+static void fflush_and__exit(void)
+{
+ fflush_all();
+ _exit(xfunc_error_retval);
+}
+
+/* After [v]fork, in child: do not restore tty pgrp on xfunc death */
+# define disable_restore_tty_pgrp_on_exit() (die_func = fflush_and__exit)
+/* After [v]fork, in parent: restore tty pgrp on xfunc death */
+# define enable_restore_tty_pgrp_on_exit() (die_func = restore_ttypgrp_and__exit)
+
+/* Restores tty foreground process group, and exits.
+ * May be called as signal handler for fatal signal
+ * (will resend signal to itself, producing correct exit state)
+ * or called directly with -EXITCODE.
+ * We also call it if xfunc is exiting.
+ */
+static void sigexit(int sig) NORETURN;
+static void sigexit(int sig)
+{
+ /* Careful: we can end up here after [v]fork. Do not restore
+ * tty pgrp then, only top-level shell process does that */
+ if (G_saved_tty_pgrp && getpid() == G.root_pid) {
+ /* Disable all signals: job control, SIGPIPE, etc.
+ * Mostly paranoid measure, to prevent infinite SIGTTOU.
+ */
+ sigprocmask_allsigs(SIG_BLOCK);
+ tcsetpgrp(G_interactive_fd, G_saved_tty_pgrp);
+ }
+
+ /* Not a signal, just exit */
+ if (sig <= 0)
+ _exit(- sig);
+
+ kill_myself_with_sig(sig); /* does not return */
+}
+#else
+
+# define disable_restore_tty_pgrp_on_exit() ((void)0)
+# define enable_restore_tty_pgrp_on_exit() ((void)0)
+
+#endif
+
+static sighandler_t pick_sighandler(unsigned sig)
+{
+ sighandler_t handler = SIG_DFL;
+ if (sig < sizeof(unsigned)*8) {
+ unsigned sigmask = (1 << sig);
+
+#if ENABLE_HUSH_JOB
+ /* is sig fatal? */
+ if (G_fatal_sig_mask & sigmask)
+ handler = sigexit;
+ else
+#endif
+ /* sig has special handling? */
+ if (G.special_sig_mask & sigmask) {
+ handler = record_pending_signo;
+ /* TTIN/TTOU/TSTP can't be set to record_pending_signo
+ * in order to ignore them: they will be raised
+ * in an endless loop when we try to do some
+ * terminal ioctls! We do have to _ignore_ these.
+ */
+ if (SPECIAL_JOBSTOP_SIGS & sigmask)
+ handler = SIG_IGN;
+ }
+ }
+ return handler;
+}
+
+/* Restores tty foreground process group, and exits. */
+static void hush_exit(int exitcode)
+{
+#if ENABLE_FEATURE_EDITING_SAVE_ON_EXIT
+ save_history(G.line_input_state); /* may be NULL */
+#endif
+
+ fflush_all();
+ if (G.exiting <= 0 && G_traps && G_traps[0] && G_traps[0][0]) {
+ char *argv[3];
+ /* argv[0] is unused */
+ argv[1] = xstrdup(G_traps[0]); /* copy, since EXIT trap handler may modify G_traps[0] */
+ argv[2] = NULL;
+ G.exiting = 1; /* prevent EXIT trap recursion */
+ /* Note: G_traps[0] is not cleared!
+ * "trap" will still show it, if executed
+ * in the handler */
+ builtin_eval(argv);
+ }
+
+#if ENABLE_FEATURE_CLEAN_UP
+ {
+ struct variable *cur_var;
+ if (G.cwd != bb_msg_unknown)
+ free((char*)G.cwd);
+ cur_var = G.top_var;
+ while (cur_var) {
+ struct variable *tmp = cur_var;
+ if (!cur_var->max_len)
+ free(cur_var->varstr);
+ cur_var = cur_var->next;
+ free(tmp);
+ }
+ }
+#endif
+
+ fflush_all();
+#if ENABLE_HUSH_JOB
+ sigexit(- (exitcode & 0xff));
+#else
+ _exit(exitcode);
+#endif
+}
+
+//TODO: return a mask of ALL handled sigs?
+static int check_and_run_traps(void)
+{
+ int last_sig = 0;
+
+ while (1) {
+ int sig;
+
+ if (sigisemptyset(&G.pending_set))
+ break;
+ sig = 0;
+ do {
+ sig++;
+ if (sigismember(&G.pending_set, sig)) {
+ sigdelset(&G.pending_set, sig);
+ goto got_sig;
+ }
+ } while (sig < NSIG);
+ break;
+ got_sig:
+#if ENABLE_HUSH_TRAP
+ if (G_traps && G_traps[sig]) {
+ debug_printf_exec("%s: sig:%d handler:'%s'\n", __func__, sig, G.traps[sig]);
+ if (G_traps[sig][0]) {
+ /* We have user-defined handler */
+ smalluint save_rcode;
+ int save_pre;
+ char *argv[3];
+ /* argv[0] is unused */
+ argv[1] = xstrdup(G_traps[sig]);
+ /* why strdup? trap can modify itself: trap 'trap "echo oops" INT' INT */
+ argv[2] = NULL;
+ save_pre = G.pre_trap_exitcode;
+ G.pre_trap_exitcode = save_rcode = G.last_exitcode;
+ builtin_eval(argv);
+ free(argv[1]);
+ G.pre_trap_exitcode = save_pre;
+ G.last_exitcode = save_rcode;
+# if ENABLE_HUSH_FUNCTIONS
+ if (G.return_exitcode >= 0) {
+ debug_printf_exec("trap exitcode:%d\n", G.return_exitcode);
+ G.last_exitcode = G.return_exitcode;
+ }
+# endif
+ last_sig = sig;
+ } /* else: "" trap, ignoring signal */
+ continue;
+ }
+#endif
+ /* not a trap: special action */
+ switch (sig) {
+ case SIGINT:
+ debug_printf_exec("%s: sig:%d default SIGINT handler\n", __func__, sig);
+ G.flag_SIGINT = 1;
+ last_sig = sig;
+ break;
+#if ENABLE_HUSH_JOB
+ case SIGHUP: {
+//TODO: why are we doing this? ash and dash don't do this,
+//they have no handler for SIGHUP at all,
+//they rely on kernel to send SIGHUP+SIGCONT to orphaned process groups
+ struct pipe *job;
+ debug_printf_exec("%s: sig:%d default SIGHUP handler\n", __func__, sig);
+ /* bash is observed to signal whole process groups,
+ * not individual processes */
+ for (job = G.job_list; job; job = job->next) {
+ if (job->pgrp <= 0)
+ continue;
+ debug_printf_exec("HUPing pgrp %d\n", job->pgrp);
+ if (kill(- job->pgrp, SIGHUP) == 0)
+ kill(- job->pgrp, SIGCONT);
+ }
+ sigexit(SIGHUP);
+ }
+#endif
+#if ENABLE_HUSH_FAST
+ case SIGCHLD:
+ debug_printf_exec("%s: sig:%d default SIGCHLD handler\n", __func__, sig);
+ G.count_SIGCHLD++;
+//bb_error_msg("[%d] check_and_run_traps: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
+ /* Note:
+ * We don't do 'last_sig = sig' here -> NOT returning this sig.
+ * This simplifies wait builtin a bit.
+ */
+ break;
+#endif
+ default: /* ignored: */
+ debug_printf_exec("%s: sig:%d default handling is to ignore\n", __func__, sig);
+ /* SIGTERM, SIGQUIT, SIGTTIN, SIGTTOU, SIGTSTP */
+ /* Note:
+ * We don't do 'last_sig = sig' here -> NOT returning this sig.
+ * Example: wait is not interrupted by TERM
+ * in interactive shell, because TERM is ignored.
+ */
+ break;
+ }
+ }
+ return last_sig;
+}
+
+
+static const char *get_cwd(int force)
+{
+ if (force || G.cwd == NULL) {
+ /* xrealloc_getcwd_or_warn(arg) calls free(arg),
+ * we must not try to free(bb_msg_unknown) */
+ if (G.cwd == bb_msg_unknown)
+ G.cwd = NULL;
+ G.cwd = xrealloc_getcwd_or_warn((char *)G.cwd);
+ if (!G.cwd)
+ G.cwd = bb_msg_unknown;
+ }
+ return G.cwd;
+}
+
+
+/*
+ * Shell and environment variable support
+ */
+static struct variable **get_ptr_to_local_var(const char *name, unsigned len)
+{
+ struct variable **pp;
+ struct variable *cur;
+
+ pp = &G.top_var;
+ while ((cur = *pp) != NULL) {
+ if (strncmp(cur->varstr, name, len) == 0 && cur->varstr[len] == '=')
+ return pp;
+ pp = &cur->next;
+ }
+ return NULL;
+}
+
+static const char* FAST_FUNC get_local_var_value(const char *name)
+{
+ struct variable **vpp;
+ unsigned len = strlen(name);
+
+ if (G.expanded_assignments) {
+ char **cpp = G.expanded_assignments;
+ while (*cpp) {
+ char *cp = *cpp;
+ if (strncmp(cp, name, len) == 0 && cp[len] == '=')
+ return cp + len + 1;
+ cpp++;
+ }
+ }
+
+ vpp = get_ptr_to_local_var(name, len);
+ if (vpp)
+ return (*vpp)->varstr + len + 1;
+
+ if (strcmp(name, "PPID") == 0)
+ return utoa(G.root_ppid);
+ // bash compat: UID? EUID?
+#if ENABLE_HUSH_RANDOM_SUPPORT
+ if (strcmp(name, "RANDOM") == 0)
+ return utoa(next_random(&G.random_gen));
+#endif
+#if ENABLE_HUSH_LINENO_VAR
+ if (strcmp(name, "LINENO") == 0)
+ return utoa(G.execute_lineno);
+#endif
+#if BASH_EPOCH_VARS
+ {
+ const char *fmt = NULL;
+ if (strcmp(name, "EPOCHSECONDS") == 0)
+ fmt = "%llu";
+ else if (strcmp(name, "EPOCHREALTIME") == 0)
+ fmt = "%llu.%06u";
+ if (fmt) {
+ struct timeval tv;
+ xgettimeofday(&tv);
+ sprintf(G.epoch_buf, fmt, (unsigned long long)tv.tv_sec,
+ (unsigned)tv.tv_usec);
+ return G.epoch_buf;
+ }
+ }
+#endif
+ return NULL;
+}
+
+#if ENABLE_HUSH_GETOPTS
+static void handle_changed_special_names(const char *name, unsigned name_len)
+{
+ if (name_len == 6) {
+ if (strncmp(name, "OPTIND", 6) == 0) {
+ G.getopt_count = 0;
+ return;
+ }
+ }
+}
+#else
+/* Do not even bother evaluating arguments */
+# define handle_changed_special_names(...) ((void)0)
+#endif
+
+/* str holds "NAME=VAL" and is expected to be malloced.
+ * We take ownership of it.
+ */
+#define SETFLAG_EXPORT (1 << 0)
+#define SETFLAG_UNEXPORT (1 << 1)
+#define SETFLAG_MAKE_RO (1 << 2)
+#define SETFLAG_VARLVL_SHIFT 3
+static int set_local_var(char *str, unsigned flags)
+{
+ struct variable **cur_pp;
+ struct variable *cur;
+ char *free_me = NULL;
+ char *eq_sign;
+ int name_len;
+ int retval;
+ unsigned local_lvl = (flags >> SETFLAG_VARLVL_SHIFT);
+
+ eq_sign = strchr(str, '=');
+ if (HUSH_DEBUG && !eq_sign)
+ bb_simple_error_msg_and_die("BUG in setvar");
+
+ name_len = eq_sign - str + 1; /* including '=' */
+ cur_pp = &G.top_var;
+ while ((cur = *cur_pp) != NULL) {
+ if (strncmp(cur->varstr, str, name_len) != 0) {
+ cur_pp = &cur->next;
+ continue;
+ }
+
+ /* We found an existing var with this name */
+ if (cur->flg_read_only) {
+ bb_error_msg("%s: readonly variable", str);
+ free(str);
+//NOTE: in bash, assignment in "export READONLY_VAR=Z" fails, and sets $?=1,
+//but export per se succeeds (does put the var in env). We don't mimic that.
+ return -1;
+ }
+ if (flags & SETFLAG_UNEXPORT) { // && cur->flg_export ?
+ debug_printf_env("%s: unsetenv '%s'\n", __func__, str);
+ *eq_sign = '\0';
+ unsetenv(str);
+ *eq_sign = '=';
+ }
+ if (cur->var_nest_level < local_lvl) {
+ /* bash 3.2.33(1) and exported vars:
+ * # export z=z
+ * # f() { local z=a; env | grep ^z; }
+ * # f
+ * z=a
+ * # env | grep ^z
+ * z=z
+ */
+ if (cur->flg_export)
+ flags |= SETFLAG_EXPORT;
+ /* New variable is local ("local VAR=VAL" or
+ * "VAR=VAL cmd")
+ * and existing one is global, or local
+ * on a lower level that new one.
+ * Remove it from global variable list:
+ */
+ *cur_pp = cur->next;
+ if (G.shadowed_vars_pp) {
+ /* Save in "shadowed" list */
+ debug_printf_env("shadowing %s'%s'/%u by '%s'/%u\n",
+ cur->flg_export ? "exported " : "",
+ cur->varstr, cur->var_nest_level, str, local_lvl
+ );
+ cur->next = *G.shadowed_vars_pp;
+ *G.shadowed_vars_pp = cur;
+ } else {
+ /* Came from pseudo_exec_argv(), no need to save: delete it */
+ debug_printf_env("shadow-deleting %s'%s'/%u by '%s'/%u\n",
+ cur->flg_export ? "exported " : "",
+ cur->varstr, cur->var_nest_level, str, local_lvl
+ );
+ if (cur->max_len == 0) /* allocated "VAR=VAL"? */
+ free_me = cur->varstr; /* then free it later */
+ free(cur);
+ }
+ break;
+ }
+
+ if (strcmp(cur->varstr + name_len, eq_sign + 1) == 0) {
+ debug_printf_env("assignement '%s' does not change anything\n", str);
+ free_and_exp:
+ free(str);
+ goto exp;
+ }
+
+ /* Replace the value in the found "struct variable" */
+ if (cur->max_len != 0) {
+ if (cur->max_len >= strnlen(str, cur->max_len + 1)) {
+ /* This one is from startup env, reuse space */
+ debug_printf_env("reusing startup env for '%s'\n", str);
+ strcpy(cur->varstr, str);
+ goto free_and_exp;
+ }
+ /* Can't reuse */
+ cur->max_len = 0;
+ goto set_str_and_exp;
+ }
+ /* max_len == 0 signifies "malloced" var, which we can
+ * (and have to) free. But we can't free(cur->varstr) here:
+ * if cur->flg_export is 1, it is in the environment.
+ * We should either unsetenv+free, or wait until putenv,
+ * then putenv(new)+free(old).
+ */
+ free_me = cur->varstr;
+ goto set_str_and_exp;
+ }
+
+ /* Not found or shadowed - create new variable struct */
+ debug_printf_env("%s: alloc new var '%s'/%u\n", __func__, str, local_lvl);
+ cur = xzalloc(sizeof(*cur));
+ cur->var_nest_level = local_lvl;
+ cur->next = *cur_pp;
+ *cur_pp = cur;
+
+ set_str_and_exp:
+ cur->varstr = str;
+ exp:
+#if !BB_MMU || ENABLE_HUSH_READONLY
+ if (flags & SETFLAG_MAKE_RO) {
+ cur->flg_read_only = 1;
+ }
+#endif
+ if (flags & SETFLAG_EXPORT)
+ cur->flg_export = 1;
+ retval = 0;
+ if (cur->flg_export) {
+ if (flags & SETFLAG_UNEXPORT) {
+ cur->flg_export = 0;
+ /* unsetenv was already done */
+ } else {
+ debug_printf_env("%s: putenv '%s'/%u\n", __func__, cur->varstr, cur->var_nest_level);
+ retval = putenv(cur->varstr);
+ /* fall through to "free(free_me)" -
+ * only now we can free old exported malloced string
+ */
+ }
+ }
+ free(free_me);
+
+ handle_changed_special_names(cur->varstr, name_len - 1);
+
+ return retval;
+}
+
+static void FAST_FUNC set_local_var_from_halves(const char *name, const char *val)
+{
+ char *var = xasprintf("%s=%s", name, val);
+ set_local_var(var, /*flag:*/ 0);
+}
+
+/* Used at startup and after each cd */
+static void set_pwd_var(unsigned flag)
+{
+ set_local_var(xasprintf("PWD=%s", get_cwd(/*force:*/ 1)), flag);
+}
+
+#if ENABLE_HUSH_UNSET || ENABLE_HUSH_GETOPTS
+static int unset_local_var_len(const char *name, int name_len)
+{
+ struct variable *cur;
+ struct variable **cur_pp;
+
+ cur_pp = &G.top_var;
+ while ((cur = *cur_pp) != NULL) {
+ if (strncmp(cur->varstr, name, name_len) == 0
+ && cur->varstr[name_len] == '='
+ ) {
+ if (cur->flg_read_only) {
+ bb_error_msg("%s: readonly variable", name);
+ return EXIT_FAILURE;
+ }
+
+ *cur_pp = cur->next;
+ debug_printf_env("%s: unsetenv '%s'\n", __func__, cur->varstr);
+ bb_unsetenv(cur->varstr);
+ if (!cur->max_len)
+ free(cur->varstr);
+ free(cur);
+
+ break;
+ }
+ cur_pp = &cur->next;
+ }
+
+ /* Handle "unset LINENO" et al even if did not find the variable to unset */
+ handle_changed_special_names(name, name_len);
+
+ return EXIT_SUCCESS;
+}
+
+static int unset_local_var(const char *name)
+{
+ return unset_local_var_len(name, strlen(name));
+}
+#endif
+
+
+/*
+ * Helpers for "var1=val1 var2=val2 cmd" feature
+ */
+static void add_vars(struct variable *var)
+{
+ struct variable *next;
+
+ while (var) {
+ next = var->next;
+ var->next = G.top_var;
+ G.top_var = var;
+ if (var->flg_export) {
+ debug_printf_env("%s: restoring exported '%s'/%u\n", __func__, var->varstr, var->var_nest_level);
+ putenv(var->varstr);
+ } else {
+ debug_printf_env("%s: restoring variable '%s'/%u\n", __func__, var->varstr, var->var_nest_level);
+ }
+ var = next;
+ }
+}
+
+/* We put strings[i] into variable table and possibly putenv them.
+ * If variable is read only, we can free the strings[i]
+ * which attempts to overwrite it.
+ * The strings[] vector itself is freed.
+ */
+static void set_vars_and_save_old(char **strings)
+{
+ char **s;
+
+ if (!strings)
+ return;
+
+ s = strings;
+ while (*s) {
+ struct variable *var_p;
+ struct variable **var_pp;
+ char *eq;
+
+ eq = strchr(*s, '=');
+ if (HUSH_DEBUG && !eq)
+ bb_simple_error_msg_and_die("BUG in varexp4");
+ var_pp = get_ptr_to_local_var(*s, eq - *s);
+ if (var_pp) {
+ var_p = *var_pp;
+ if (var_p->flg_read_only) {
+ char **p;
+ bb_error_msg("%s: readonly variable", *s);
+ /*
+ * "VAR=V BLTIN" unsets VARs after BLTIN completes.
+ * If VAR is readonly, leaving it in the list
+ * after asssignment error (msg above)
+ * causes doubled error message later, on unset.
+ */
+ debug_printf_env("removing/freeing '%s' element\n", *s);
+ free(*s);
+ p = s;
+ do { *p = p[1]; p++; } while (*p);
+ goto next;
+ }
+ /* below, set_local_var() with nest level will
+ * "shadow" (remove) this variable from
+ * global linked list.
+ */
+ }
+ debug_printf_env("%s: env override '%s'/%u\n", __func__, *s, G.var_nest_level);
+ set_local_var(*s, (G.var_nest_level << SETFLAG_VARLVL_SHIFT) | SETFLAG_EXPORT);
+ s++;
+ next: ;
+ }
+ free(strings);
+}
+
+
+/*
+ * Unicode helper
+ */
+static void reinit_unicode_for_hush(void)
+{
+ /* Unicode support should be activated even if LANG is set
+ * _during_ shell execution, not only if it was set when
+ * shell was started. Therefore, re-check LANG every time:
+ */
+ if (ENABLE_FEATURE_CHECK_UNICODE_IN_ENV
+ || ENABLE_UNICODE_USING_LOCALE
+ ) {
+ const char *s = get_local_var_value("LC_ALL");
+ if (!s) s = get_local_var_value("LC_CTYPE");
+ if (!s) s = get_local_var_value("LANG");
+ reinit_unicode(s);
+ }
+}
+
+/*
+ * in_str support (strings, and "strings" read from files).
+ */
+
+#if ENABLE_HUSH_INTERACTIVE
+/* To test correct lineedit/interactive behavior, type from command line:
+ * echo $P\
+ * \
+ * AT\
+ * H\
+ * \
+ * It exercises a lot of corner cases.
+ */
+static const char *setup_prompt_string(void)
+{
+ const char *prompt_str;
+
+ debug_printf_prompt("%s promptmode:%d\n", __func__, G.promptmode);
+
+# if ENABLE_FEATURE_EDITING_FANCY_PROMPT
+ prompt_str = get_local_var_value(G.promptmode == 0 ? "PS1" : "PS2");
+ if (!prompt_str)
+ prompt_str = "";
+# else
+ prompt_str = "> "; /* if PS2, else... */
+ if (G.promptmode == 0) { /* PS1 */
+ /* No fancy prompts supported, (re)generate "CURDIR $ " by hand */
+ free(G.PS1);
+ /* bash uses $PWD value, even if it is set by user.
+ * It uses current dir only if PWD is unset.
+ * We always use current dir. */
+ prompt_str = G.PS1 = xasprintf("%s %c ", get_cwd(0), (geteuid() != 0) ? '$' : '#');
+ }
+# endif
+ debug_printf("prompt_str '%s'\n", prompt_str);
+ return prompt_str;
+}
+static int get_user_input(struct in_str *i)
+{
+# if ENABLE_FEATURE_EDITING
+ /* In EDITING case, this function reads next input line,
+ * saves it in i->p, then returns 1st char of it.
+ */
+ int r;
+ const char *prompt_str;
+
+ prompt_str = setup_prompt_string();
+ for (;;) {
+ reinit_unicode_for_hush();
+ G.flag_SIGINT = 0;
+ /* buglet: SIGINT will not make new prompt to appear _at once_,
+ * only after <Enter>. (^C works immediately) */
+ r = read_line_input(G.line_input_state, prompt_str,
+ G.user_input_buf, CONFIG_FEATURE_EDITING_MAX_LEN-1
+ );
+ /* read_line_input intercepts ^C, "convert" it to SIGINT */
+ if (r == 0) {
+ raise(SIGINT);
+ }
+ check_and_run_traps();
+ if (r != 0 && !G.flag_SIGINT)
+ break;
+ /* ^C or SIGINT: repeat */
+ /* bash prints ^C even on real SIGINT (non-kbd generated) */
+ write(STDOUT_FILENO, "^C\n", 3);
+ G.last_exitcode = 128 | SIGINT;
+ }
+ if (r < 0) {
+ /* EOF/error detected */
+ /* ^D on interactive input goes to next line before exiting: */
+ write(STDOUT_FILENO, "\n", 1);
+ i->p = NULL;
+ i->peek_buf[0] = r = EOF;
+ return r;
+ }
+ i->p = G.user_input_buf;
+ return (unsigned char)*i->p++;
+# else
+ /* In !EDITING case, this function gets called for every char.
+ * Buffering happens deeper in the call chain, in hfgetc(i->file).
+ */
+ int r;
+
+ for (;;) {
+ G.flag_SIGINT = 0;
+ if (i->last_char == '\0' || i->last_char == '\n') {
+ const char *prompt_str = setup_prompt_string();
+ /* Why check_and_run_traps here? Try this interactively:
+ * $ trap 'echo INT' INT; (sleep 2; kill -INT $$) &
+ * $ <[enter], repeatedly...>
+ * Without check_and_run_traps, handler never runs.
+ */
+ check_and_run_traps();
+ fputs_stdout(prompt_str);
+ fflush_all();
+ }
+ r = hfgetc(i->file);
+ /* In !ENABLE_FEATURE_EDITING we don't use read_line_input,
+ * no ^C masking happens during fgetc, no special code for ^C:
+ * it generates SIGINT as usual.
+ */
+ check_and_run_traps();
+ if (r != '\0' && !G.flag_SIGINT)
+ break;
+ if (G.flag_SIGINT) {
+ /* ^C or SIGINT: repeat */
+ /* bash prints ^C even on real SIGINT (non-kbd generated) */
+ /* kernel prints "^C" itself, just print newline: */
+ write(STDOUT_FILENO, "\n", 1);
+ G.last_exitcode = 128 | SIGINT;
+ }
+ }
+ return r;
+# endif
+}
+/* This is the magic location that prints prompts
+ * and gets data back from the user */
+static int fgetc_interactive(struct in_str *i)
+{
+ int ch;
+ /* If it's interactive stdin, get new line. */
+ if (G_interactive_fd && i->file == G.HFILE_stdin) {
+ /* Returns first char (or EOF), the rest is in i->p[] */
+ ch = get_user_input(i);
+ G.promptmode = 1; /* PS2 */
+ debug_printf_prompt("%s promptmode=%d\n", __func__, G.promptmode);
+ } else {
+ /* Not stdin: script file, sourced file, etc */
+ do ch = hfgetc(i->file); while (ch == '\0');
+ }
+ return ch;
+}
+#else /* !INTERACTIVE */
+static ALWAYS_INLINE int fgetc_interactive(struct in_str *i)
+{
+ int ch;
+ do ch = hfgetc(i->file); while (ch == '\0');
+ return ch;
+}
+#endif /* !INTERACTIVE */
+
+static int i_getch(struct in_str *i)
+{
+ int ch;
+
+ if (!i->file) {
+ /* string-based in_str */
+ ch = (unsigned char)*i->p;
+ if (ch != '\0') {
+ i->p++;
+ i->last_char = ch;
+ return ch;
+ }
+ return EOF;
+ }
+
+ /* FILE-based in_str */
+
+#if ENABLE_FEATURE_EDITING
+ /* This can be stdin, check line editing char[] buffer */
+ if (i->p && *i->p != '\0') {
+ ch = (unsigned char)*i->p++;
+ goto out;
+ }
+#endif
+ /* peek_buf[] is an int array, not char. Can contain EOF. */
+ ch = i->peek_buf[0];
+ if (ch != 0) {
+ int ch2 = i->peek_buf[1];
+ i->peek_buf[0] = ch2;
+ if (ch2 == 0) /* very likely, avoid redundant write */
+ goto out;
+ i->peek_buf[1] = 0;
+ goto out;
+ }
+
+ ch = fgetc_interactive(i);
+ out:
+ debug_printf("file_get: got '%c' %d\n", ch, ch);
+ i->last_char = ch;
+#if ENABLE_HUSH_LINENO_VAR
+ if (ch == '\n') {
+ G.parse_lineno++;
+ debug_printf_parse("G.parse_lineno++ = %u\n", G.parse_lineno);
+ }
+#endif
+ return ch;
+}
+
+static int i_peek(struct in_str *i)
+{
+ int ch;
+
+ if (!i->file) {
+ /* string-based in_str */
+ /* Doesn't report EOF on NUL. None of the callers care. */
+ return (unsigned char)*i->p;
+ }
+
+ /* FILE-based in_str */
+
+#if ENABLE_FEATURE_EDITING && ENABLE_HUSH_INTERACTIVE
+ /* This can be stdin, check line editing char[] buffer */
+ if (i->p && *i->p != '\0')
+ return (unsigned char)*i->p;
+#endif
+ /* peek_buf[] is an int array, not char. Can contain EOF. */
+ ch = i->peek_buf[0];
+ if (ch != 0)
+ return ch;
+
+ /* Need to get a new char */
+ ch = fgetc_interactive(i);
+ debug_printf("file_peek: got '%c' %d\n", ch, ch);
+
+ /* Save it by either rolling back line editing buffer, or in i->peek_buf[0] */
+#if ENABLE_FEATURE_EDITING && ENABLE_HUSH_INTERACTIVE
+ if (i->p) {
+ i->p -= 1;
+ return ch;
+ }
+#endif
+ i->peek_buf[0] = ch;
+ /*i->peek_buf[1] = 0; - already is */
+ return ch;
+}
+
+/* Only ever called if i_peek() was called, and did not return EOF.
+ * IOW: we know the previous peek saw an ordinary char, not EOF, not NUL,
+ * not end-of-line. Therefore we never need to read a new editing line here.
+ */
+static int i_peek2(struct in_str *i)
+{
+ int ch;
+
+ /* There are two cases when i->p[] buffer exists.
+ * (1) it's a string in_str.
+ * (2) It's a file, and we have a saved line editing buffer.
+ * In both cases, we know that i->p[0] exists and not NUL, and
+ * the peek2 result is in i->p[1].
+ */
+ if (i->p)
+ return (unsigned char)i->p[1];
+
+ /* Now we know it is a file-based in_str. */
+
+ /* peek_buf[] is an int array, not char. Can contain EOF. */
+ /* Is there 2nd char? */
+ ch = i->peek_buf[1];
+ if (ch == 0) {
+ /* We did not read it yet, get it now */
+ do ch = hfgetc(i->file); while (ch == '\0');
+ i->peek_buf[1] = ch;
+ }
+
+ debug_printf("file_peek2: got '%c' %d\n", ch, ch);
+ return ch;
+}
+
+static int i_getch_and_eat_bkslash_nl(struct in_str *input)
+{
+ for (;;) {
+ int ch, ch2;
+
+ ch = i_getch(input);
+ if (ch != '\\')
+ return ch;
+ ch2 = i_peek(input);
+ if (ch2 != '\n')
+ return ch;
+ /* backslash+newline, skip it */
+ i_getch(input);
+ }
+}
+
+/* Note: this function _eats_ \<newline> pairs, safe to use plain
+ * i_getch() after it instead of i_getch_and_eat_bkslash_nl().
+ */
+static int i_peek_and_eat_bkslash_nl(struct in_str *input)
+{
+ for (;;) {
+ int ch, ch2;
+
+ ch = i_peek(input);
+ if (ch != '\\')
+ return ch;
+ ch2 = i_peek2(input);
+ if (ch2 != '\n')
+ return ch;
+ /* backslash+newline, skip it */
+ i_getch(input);
+ i_getch(input);
+ }
+}
+
+static void setup_file_in_str(struct in_str *i, HFILE *fp)
+{
+ memset(i, 0, sizeof(*i));
+ i->file = fp;
+ /* i->p = NULL; */
+}
+
+static void setup_string_in_str(struct in_str *i, const char *s)
+{
+ memset(i, 0, sizeof(*i));
+ /*i->file = NULL */;
+ i->p = s;
+}
+
+
+/*
+ * o_string support
+ */
+#define B_CHUNK (32 * sizeof(char*))
+
+static void o_reset_to_empty_unquoted(o_string *o)
+{
+ o->length = 0;
+ o->has_quoted_part = 0;
+ if (o->data)
+ o->data[0] = '\0';
+}
+
+static void o_free_and_set_NULL(o_string *o)
+{
+ free(o->data);
+ memset(o, 0, sizeof(*o));
+}
+
+static ALWAYS_INLINE void o_free(o_string *o)
+{
+ free(o->data);
+}
+
+static void o_grow_by(o_string *o, int len)
+{
+ if (o->length + len > o->maxlen) {
+ o->maxlen += (2 * len) | (B_CHUNK-1);
+ o->data = xrealloc(o->data, 1 + o->maxlen);
+ }
+}
+
+static void o_addchr(o_string *o, int ch)
+{
+ debug_printf("o_addchr: '%c' o->length=%d o=%p\n", ch, o->length, o);
+ if (o->length < o->maxlen) {
+ /* likely. avoid o_grow_by() call */
+ add:
+ o->data[o->length] = ch;
+ o->length++;
+ o->data[o->length] = '\0';
+ return;
+ }
+ o_grow_by(o, 1);
+ goto add;
+}
+
+#if 0
+/* Valid only if we know o_string is not empty */
+static void o_delchr(o_string *o)
+{
+ o->length--;
+ o->data[o->length] = '\0';
+}
+#endif
+
+static void o_addblock(o_string *o, const char *str, int len)
+{
+ o_grow_by(o, len);
+ ((char*)mempcpy(&o->data[o->length], str, len))[0] = '\0';
+ o->length += len;
+}
+
+static void o_addstr(o_string *o, const char *str)
+{
+ o_addblock(o, str, strlen(str));
+}
+
+static void o_addstr_with_NUL(o_string *o, const char *str)
+{
+ o_addblock(o, str, strlen(str) + 1);
+}
+
+#if !BB_MMU
+static void nommu_addchr(o_string *o, int ch)
+{
+ if (o)
+ o_addchr(o, ch);
+}
+#else
+# define nommu_addchr(o, str) ((void)0)
+#endif
+
+#if ENABLE_HUSH_MODE_X
+static void x_mode_addchr(int ch)
+{
+ o_addchr(&G.x_mode_buf, ch);
+}
+static void x_mode_addstr(const char *str)
+{
+ o_addstr(&G.x_mode_buf, str);
+}
+static void x_mode_addblock(const char *str, int len)
+{
+ o_addblock(&G.x_mode_buf, str, len);
+}
+static void x_mode_prefix(void)
+{
+ int n = G.x_mode_depth;
+ do x_mode_addchr('+'); while (--n >= 0);
+}
+static void x_mode_flush(void)
+{
+ int len = G.x_mode_buf.length;
+ if (len <= 0)
+ return;
+ if (G.x_mode_fd > 0) {
+ G.x_mode_buf.data[len] = '\n';
+ full_write(G.x_mode_fd, G.x_mode_buf.data, len + 1);
+ }
+ G.x_mode_buf.length = 0;
+}
+#endif
+
+/*
+ * HUSH_BRACE_EXPANSION code needs corresponding quoting on variable expansion side.
+ * Currently, "v='{q,w}'; echo $v" erroneously expands braces in $v.
+ * Apparently, on unquoted $v bash still does globbing
+ * ("v='*.txt'; echo $v" prints all .txt files),
+ * but NOT brace expansion! Thus, there should be TWO independent
+ * quoting mechanisms on $v expansion side: one protects
+ * $v from brace expansion, and other additionally protects "$v" against globbing.
+ * We have only second one.
+ */
+
+#if ENABLE_HUSH_BRACE_EXPANSION
+# define MAYBE_BRACES "{}"
+#else
+# define MAYBE_BRACES ""
+#endif
+
+/* My analysis of quoting semantics tells me that state information
+ * is associated with a destination, not a source.
+ */
+static void o_addqchr(o_string *o, int ch)
+{
+ int sz = 1;
+ /* '-' is included because of this case:
+ * >filename0 >filename1 >filename9; v='-'; echo filename[0"$v"9]
+ */
+ char *found = strchr("*?[-\\" MAYBE_BRACES, ch);
+ if (found)
+ sz++;
+ o_grow_by(o, sz);
+ if (found) {
+ o->data[o->length] = '\\';
+ o->length++;
+ }
+ o->data[o->length] = ch;
+ o->length++;
+ o->data[o->length] = '\0';
+}
+
+static void o_addQchr(o_string *o, int ch)
+{
+ int sz = 1;
+ if ((o->o_expflags & EXP_FLAG_ESC_GLOB_CHARS)
+ && strchr("*?[-\\" MAYBE_BRACES, ch)
+ ) {
+ sz++;
+ o->data[o->length] = '\\';
+ o->length++;
+ }
+ o_grow_by(o, sz);
+ o->data[o->length] = ch;
+ o->length++;
+ o->data[o->length] = '\0';
+}
+
+static void o_addqblock(o_string *o, const char *str, int len)
+{
+ while (len) {
+ char ch;
+ int sz;
+ int ordinary_cnt = strcspn(str, "*?[-\\" MAYBE_BRACES);
+ if (ordinary_cnt > len) /* paranoia */
+ ordinary_cnt = len;
+ o_addblock(o, str, ordinary_cnt);
+ if (ordinary_cnt == len)
+ return; /* NUL is already added by o_addblock */
+ str += ordinary_cnt;
+ len -= ordinary_cnt + 1; /* we are processing + 1 char below */
+
+ ch = *str++;
+ sz = 1;
+ if (ch) { /* it is necessarily one of "*?[-\\" MAYBE_BRACES */
+ sz++;
+ o->data[o->length] = '\\';
+ o->length++;
+ }
+ o_grow_by(o, sz);
+ o->data[o->length] = ch;
+ o->length++;
+ }
+ o->data[o->length] = '\0';
+}
+
+static void o_addQblock(o_string *o, const char *str, int len)
+{
+ if (!(o->o_expflags & EXP_FLAG_ESC_GLOB_CHARS)) {
+ o_addblock(o, str, len);
+ return;
+ }
+ o_addqblock(o, str, len);
+}
+
+static void o_addQstr(o_string *o, const char *str)
+{
+ o_addQblock(o, str, strlen(str));
+}
+
+/* A special kind of o_string for $VAR and `cmd` expansion.
+ * It contains char* list[] at the beginning, which is grown in 16 element
+ * increments. Actual string data starts at the next multiple of 16 * (char*).
+ * list[i] contains an INDEX (int!) into this string data.
+ * It means that if list[] needs to grow, data needs to be moved higher up
+ * but list[i]'s need not be modified.
+ * NB: remembering how many list[i]'s you have there is crucial.
+ * o_finalize_list() operation post-processes this structure - calculates
+ * and stores actual char* ptrs in list[]. Oh, it NULL terminates it as well.
+ */
+#if DEBUG_EXPAND || DEBUG_GLOB
+static void debug_print_list(const char *prefix, o_string *o, int n)
+{
+ char **list = (char**)o->data;
+ int string_start = ((n + 0xf) & ~0xf) * sizeof(list[0]);
+ int i = 0;
+
+ indent();
+ fdprintf(2, "%s: list:%p n:%d string_start:%d length:%d maxlen:%d glob:%d quoted:%d escape:%d\n",
+ prefix, list, n, string_start, o->length, o->maxlen,
+ !!(o->o_expflags & EXP_FLAG_GLOB),
+ o->has_quoted_part,
+ !!(o->o_expflags & EXP_FLAG_ESC_GLOB_CHARS));
+ while (i < n) {
+ indent();
+ fdprintf(2, " list[%d]=%d '%s' %p\n", i, (int)(uintptr_t)list[i],
+ o->data + (int)(uintptr_t)list[i] + string_start,
+ o->data + (int)(uintptr_t)list[i] + string_start);
+ i++;
+ }
+ if (n) {
+ const char *p = o->data + (int)(uintptr_t)list[n - 1] + string_start;
+ indent();
+ fdprintf(2, " total_sz:%ld\n", (long)((p + strlen(p) + 1) - o->data));
+ }
+}
+#else
+# define debug_print_list(prefix, o, n) ((void)0)
+#endif
+
+/* n = o_save_ptr_helper(str, n) "starts new string" by storing an index value
+ * in list[n] so that it points past last stored byte so far.
+ * It returns n+1. */
+static int o_save_ptr_helper(o_string *o, int n)
+{
+ char **list = (char**)o->data;
+ int string_start;
+ int string_len;
+
+ if (!o->has_empty_slot) {
+ string_start = ((n + 0xf) & ~0xf) * sizeof(list[0]);
+ string_len = o->length - string_start;
+ if (!(n & 0xf)) { /* 0, 0x10, 0x20...? */
+ debug_printf_list("list[%d]=%d string_start=%d (growing)\n", n, string_len, string_start);
+ /* list[n] points to string_start, make space for 16 more pointers */
+ o->maxlen += 0x10 * sizeof(list[0]);
+ o->data = xrealloc(o->data, o->maxlen + 1);
+ list = (char**)o->data;
+ memmove(list + n + 0x10, list + n, string_len);
+ /*
+ * expand_on_ifs() has a "previous argv[] ends in IFS?"
+ * check. (grep for -prev-ifs-check-).
+ * Ensure that argv[-1][last] is not garbage
+ * but zero bytes, to save index check there.
+ */
+ list[n + 0x10 - 1] = 0;
+ o->length += 0x10 * sizeof(list[0]);
+ } else {
+ debug_printf_list("list[%d]=%d string_start=%d\n",
+ n, string_len, string_start);
+ }
+ } else {
+ /* We have empty slot at list[n], reuse without growth */
+ string_start = ((n+1 + 0xf) & ~0xf) * sizeof(list[0]); /* NB: n+1! */
+ string_len = o->length - string_start;
+ debug_printf_list("list[%d]=%d string_start=%d (empty slot)\n",
+ n, string_len, string_start);
+ o->has_empty_slot = 0;
+ }
+ o->has_quoted_part = 0;
+ list[n] = (char*)(uintptr_t)string_len;
+ return n + 1;
+}
+
+/* "What was our last o_save_ptr'ed position (byte offset relative o->data)?" */
+static int o_get_last_ptr(o_string *o, int n)
+{
+ char **list = (char**)o->data;
+ int string_start = ((n + 0xf) & ~0xf) * sizeof(list[0]);
+
+ return ((int)(uintptr_t)list[n-1]) + string_start;
+}
+
+/*
+ * Globbing routines.
+ *
+ * Most words in commands need to be globbed, even ones which are
+ * (single or double) quoted. This stems from the possiblity of
+ * constructs like "abc"* and 'abc'* - these should be globbed.
+ * Having a different code path for fully-quoted strings ("abc",
+ * 'abc') would only help performance-wise, but we still need
+ * code for partially-quoted strings.
+ *
+ * Unfortunately, if we want to match bash and ash behavior in all cases,
+ * the logic can't be "shell-syntax argument is first transformed
+ * to a string, then globbed, and if globbing does not match anything,
+ * it is used verbatim". Here are two examples where it fails:
+ *
+ * echo 'b\*'?
+ *
+ * The globbing can't be avoided (because of '?' at the end).
+ * The glob pattern is: b\\\*? - IOW, both \ and * are literals
+ * and are glob-escaped. If this does not match, bash/ash print b\*?
+ * - IOW: they "unbackslash" the glob pattern.
+ * Now, look at this:
+ *
+ * v='\\\*'; echo b$v?
+ *
+ * The glob pattern is the same here: b\\\*? - the unquoted $v expansion
+ * should be used as glob pattern with no changes. However, if glob
+ * does not match, bash/ash print b\\\*? - NOT THE SAME as first example!
+ *
+ * ash implements this by having an encoded representation of the word
+ * to glob, which IS NOT THE SAME as the glob pattern - it has more data.
+ * Glob pattern is derived from it. If glob fails, the decision what result
+ * should be is made using that encoded representation. Not glob pattern.
+ */
+
+#if ENABLE_HUSH_BRACE_EXPANSION
+/* There in a GNU extension, GLOB_BRACE, but it is not usable:
+ * first, it processes even {a} (no commas), second,
+ * I didn't manage to make it return strings when they don't match
+ * existing files. Need to re-implement it.
+ */
+
+/* Helper */
+static int glob_needed(const char *s)
+{
+ while (*s) {
+ if (*s == '\\') {
+ if (!s[1])
+ return 0;
+ s += 2;
+ continue;
+ }
+ if (*s == '*' || *s == '[' || *s == '?' || *s == '{')
+ return 1;
+ s++;
+ }
+ return 0;
+}
+/* Return pointer to next closing brace or to comma */
+static const char *next_brace_sub(const char *cp)
+{
+ unsigned depth = 0;
+ cp++;
+ while (*cp != '\0') {
+ if (*cp == '\\') {
+ if (*++cp == '\0')
+ break;
+ cp++;
+ continue;
+ }
+ if ((*cp == '}' && depth-- == 0) || (*cp == ',' && depth == 0))
+ break;
+ if (*cp++ == '{')
+ depth++;
+ }
+
+ return *cp != '\0' ? cp : NULL;
+}
+/* Recursive brace globber. Note: may garble pattern[]. */
+static int glob_brace(char *pattern, o_string *o, int n)
+{
+ char *new_pattern_buf;
+ const char *begin;
+ const char *next;
+ const char *rest;
+ const char *p;
+ size_t rest_len;
+
+ debug_printf_glob("glob_brace('%s')\n", pattern);
+
+ begin = pattern;
+ while (1) {
+ if (*begin == '\0')
+ goto simple_glob;
+ if (*begin == '{') {
+ /* Find the first sub-pattern and at the same time
+ * find the rest after the closing brace */
+ next = next_brace_sub(begin);
+ if (next == NULL) {
+ /* An illegal expression */
+ goto simple_glob;
+ }
+ if (*next == '}') {
+ /* "{abc}" with no commas - illegal
+ * brace expr, disregard and skip it */
+ begin = next + 1;
+ continue;
+ }
+ break;
+ }
+ if (*begin == '\\' && begin[1] != '\0')
+ begin++;
+ begin++;
+ }
+ debug_printf_glob("begin:%s\n", begin);
+ debug_printf_glob("next:%s\n", next);
+
+ /* Now find the end of the whole brace expression */
+ rest = next;
+ while (*rest != '}') {
+ rest = next_brace_sub(rest);
+ if (rest == NULL) {
+ /* An illegal expression */
+ goto simple_glob;
+ }
+ debug_printf_glob("rest:%s\n", rest);
+ }
+ rest_len = strlen(++rest) + 1;
+
+ /* We are sure the brace expression is well-formed */
+
+ /* Allocate working buffer large enough for our work */
+ new_pattern_buf = xmalloc(strlen(pattern));
+
+ /* We have a brace expression. BEGIN points to the opening {,
+ * NEXT points past the terminator of the first element, and REST
+ * points past the final }. We will accumulate result names from
+ * recursive runs for each brace alternative in the buffer using
+ * GLOB_APPEND. */
+
+ p = begin + 1;
+ while (1) {
+ /* Construct the new glob expression */
+ memcpy(
+ mempcpy(
+ mempcpy(new_pattern_buf,
+ /* We know the prefix for all sub-patterns */
+ pattern, begin - pattern),
+ p, next - p),
+ rest, rest_len);
+
+ /* Note: glob_brace() may garble new_pattern_buf[].
+ * That's why we re-copy prefix every time (1st memcpy above).
+ */
+ n = glob_brace(new_pattern_buf, o, n);
+ if (*next == '}') {
+ /* We saw the last entry */
+ break;
+ }
+ p = next + 1;
+ next = next_brace_sub(next);
+ }
+ free(new_pattern_buf);
+ return n;
+
+ simple_glob:
+ {
+ int gr;
+ glob_t globdata;
+
+ memset(&globdata, 0, sizeof(globdata));
+ gr = glob(pattern, 0, NULL, &globdata);
+ debug_printf_glob("glob('%s'):%d\n", pattern, gr);
+ if (gr != 0) {
+ if (gr == GLOB_NOMATCH) {
+ globfree(&globdata);
+ /* NB: garbles parameter */
+ unbackslash(pattern);
+ o_addstr_with_NUL(o, pattern);
+ debug_printf_glob("glob pattern '%s' is literal\n", pattern);
+ return o_save_ptr_helper(o, n);
+ }
+ if (gr == GLOB_NOSPACE)
+ bb_die_memory_exhausted();
+ /* GLOB_ABORTED? Only happens with GLOB_ERR flag,
+ * but we didn't specify it. Paranoia again. */
+ bb_error_msg_and_die("glob error %d on '%s'", gr, pattern);
+ }
+ if (globdata.gl_pathv && globdata.gl_pathv[0]) {
+ char **argv = globdata.gl_pathv;
+ while (1) {
+ o_addstr_with_NUL(o, *argv);
+ n = o_save_ptr_helper(o, n);
+ argv++;
+ if (!*argv)
+ break;
+ }
+ }
+ globfree(&globdata);
+ }
+ return n;
+}
+/* Performs globbing on last list[],
+ * saving each result as a new list[].
+ */
+static int perform_glob(o_string *o, int n)
+{
+ char *pattern, *copy;
+
+ debug_printf_glob("start perform_glob: n:%d o->data:%p\n", n, o->data);
+ if (!o->data)
+ return o_save_ptr_helper(o, n);
+ pattern = o->data + o_get_last_ptr(o, n);
+ debug_printf_glob("glob pattern '%s'\n", pattern);
+ if (!glob_needed(pattern)) {
+ /* unbackslash last string in o in place, fix length */
+ o->length = unbackslash(pattern) - o->data;
+ debug_printf_glob("glob pattern '%s' is literal\n", pattern);
+ return o_save_ptr_helper(o, n);
+ }
+
+ copy = xstrdup(pattern);
+ /* "forget" pattern in o */
+ o->length = pattern - o->data;
+ n = glob_brace(copy, o, n);
+ free(copy);
+ if (DEBUG_GLOB)
+ debug_print_list("perform_glob returning", o, n);
+ return n;
+}
+
+#else /* !HUSH_BRACE_EXPANSION */
+
+/* Helper */
+static int glob_needed(const char *s)
+{
+ while (*s) {
+ if (*s == '\\') {
+ if (!s[1])
+ return 0;
+ s += 2;
+ continue;
+ }
+ if (*s == '*' || *s == '[' || *s == '?')
+ return 1;
+ s++;
+ }
+ return 0;
+}
+/* Performs globbing on last list[],
+ * saving each result as a new list[].
+ */
+static int perform_glob(o_string *o, int n)
+{
+ glob_t globdata;
+ int gr;
+ char *pattern;
+
+ debug_printf_glob("start perform_glob: n:%d o->data:%p\n", n, o->data);
+ if (!o->data)
+ return o_save_ptr_helper(o, n);
+ pattern = o->data + o_get_last_ptr(o, n);
+ debug_printf_glob("glob pattern '%s'\n", pattern);
+ if (!glob_needed(pattern)) {
+ literal:
+ /* unbackslash last string in o in place, fix length */
+ o->length = unbackslash(pattern) - o->data;
+ debug_printf_glob("glob pattern '%s' is literal\n", pattern);
+ return o_save_ptr_helper(o, n);
+ }
+
+ memset(&globdata, 0, sizeof(globdata));
+ /* Can't use GLOB_NOCHECK: it does not unescape the string.
+ * If we glob "*.\*" and don't find anything, we need
+ * to fall back to using literal "*.*", but GLOB_NOCHECK
+ * will return "*.\*"!
+ */
+ gr = glob(pattern, 0, NULL, &globdata);
+ debug_printf_glob("glob('%s'):%d\n", pattern, gr);
+ if (gr != 0) {
+ if (gr == GLOB_NOMATCH) {
+ globfree(&globdata);
+ goto literal;
+ }
+ if (gr == GLOB_NOSPACE)
+ bb_die_memory_exhausted();
+ /* GLOB_ABORTED? Only happens with GLOB_ERR flag,
+ * but we didn't specify it. Paranoia again. */
+ bb_error_msg_and_die("glob error %d on '%s'", gr, pattern);
+ }
+ if (globdata.gl_pathv && globdata.gl_pathv[0]) {
+ char **argv = globdata.gl_pathv;
+ /* "forget" pattern in o */
+ o->length = pattern - o->data;
+ while (1) {
+ o_addstr_with_NUL(o, *argv);
+ n = o_save_ptr_helper(o, n);
+ argv++;
+ if (!*argv)
+ break;
+ }
+ }
+ globfree(&globdata);
+ if (DEBUG_GLOB)
+ debug_print_list("perform_glob returning", o, n);
+ return n;
+}
+
+#endif /* !HUSH_BRACE_EXPANSION */
+
+/* If o->o_expflags & EXP_FLAG_GLOB, glob the string so far remembered.
+ * Otherwise, just finish current list[] and start new */
+static int o_save_ptr(o_string *o, int n)
+{
+ if (o->o_expflags & EXP_FLAG_GLOB) {
+ /* If o->has_empty_slot, list[n] was already globbed
+ * (if it was requested back then when it was filled)
+ * so don't do that again! */
+ if (!o->has_empty_slot)
+ return perform_glob(o, n); /* o_save_ptr_helper is inside */
+ }
+ return o_save_ptr_helper(o, n);
+}
+
+/* "Please convert list[n] to real char* ptrs, and NULL terminate it." */
+static char **o_finalize_list(o_string *o, int n)
+{
+ char **list;
+ int string_start;
+
+ if (DEBUG_EXPAND)
+ debug_print_list("finalized", o, n);
+ debug_printf_expand("finalized n:%d\n", n);
+ list = (char**)o->data;
+ string_start = ((n + 0xf) & ~0xf) * sizeof(list[0]);
+ list[--n] = NULL;
+ while (n) {
+ n--;
+ list[n] = o->data + (int)(uintptr_t)list[n] + string_start;
+ }
+ return list;
+}
+
+static void free_pipe_list(struct pipe *pi);
+
+/* Returns pi->next - next pipe in the list */
+static struct pipe *free_pipe(struct pipe *pi)
+{
+ struct pipe *next;
+ int i;
+
+ debug_printf_clean("free_pipe (pid %d)\n", getpid());
+ for (i = 0; i < pi->num_cmds; i++) {
+ struct command *command;
+ struct redir_struct *r, *rnext;
+
+ command = &pi->cmds[i];
+ debug_printf_clean(" command %d:\n", i);
+ if (command->argv) {
+ if (DEBUG_CLEAN) {
+ int a;
+ char **p;
+ for (a = 0, p = command->argv; *p; a++, p++) {
+ debug_printf_clean(" argv[%d] = %s\n", a, *p);
+ }
+ }
+ free_strings(command->argv);
+ //command->argv = NULL;
+ }
+ /* not "else if": on syntax error, we may have both! */
+ if (command->group) {
+ debug_printf_clean(" begin group (cmd_type:%d)\n",
+ command->cmd_type);
+ free_pipe_list(command->group);
+ debug_printf_clean(" end group\n");
+ //command->group = NULL;
+ }
+ /* else is crucial here.
+ * If group != NULL, child_func is meaningless */
+#if ENABLE_HUSH_FUNCTIONS
+ else if (command->child_func) {
+ debug_printf_exec("cmd %p releases child func at %p\n", command, command->child_func);
+ command->child_func->parent_cmd = NULL;
+ }
+#endif
+#if !BB_MMU
+ free(command->group_as_string);
+ //command->group_as_string = NULL;
+#endif
+ for (r = command->redirects; r; r = rnext) {
+ debug_printf_clean(" redirect %d%s",
+ r->rd_fd, redir_table[r->rd_type].descrip);
+ /* guard against the case >$FOO, where foo is unset or blank */
+ if (r->rd_filename) {
+ debug_printf_clean(" fname:'%s'\n", r->rd_filename);
+ free(r->rd_filename);
+ //r->rd_filename = NULL;
+ }
+ debug_printf_clean(" rd_dup:%d\n", r->rd_dup);
+ rnext = r->next;
+ free(r);
+ }
+ //command->redirects = NULL;
+ }
+ free(pi->cmds); /* children are an array, they get freed all at once */
+ //pi->cmds = NULL;
+#if ENABLE_HUSH_JOB
+ free(pi->cmdtext);
+ //pi->cmdtext = NULL;
+#endif
+
+ next = pi->next;
+ free(pi);
+ return next;
+}
+
+static void free_pipe_list(struct pipe *pi)
+{
+ while (pi) {
+#if HAS_KEYWORDS
+ debug_printf_clean("pipe reserved word %d\n", pi->res_word);
+#endif
+ debug_printf_clean("pipe followup code %d\n", pi->followup);
+ pi = free_pipe(pi);
+ }
+}
+
+
+/*** Parsing routines ***/
+
+#ifndef debug_print_tree
+static void debug_print_tree(struct pipe *pi, int lvl)
+{
+ static const char *const PIPE[] = {
+ [PIPE_SEQ] = "SEQ",
+ [PIPE_AND] = "AND",
+ [PIPE_OR ] = "OR" ,
+ [PIPE_BG ] = "BG" ,
+ };
+ static const char *RES[] = {
+ [RES_NONE ] = "NONE" ,
+# if ENABLE_HUSH_IF
+ [RES_IF ] = "IF" ,
+ [RES_THEN ] = "THEN" ,
+ [RES_ELIF ] = "ELIF" ,
+ [RES_ELSE ] = "ELSE" ,
+ [RES_FI ] = "FI" ,
+# endif
+# if ENABLE_HUSH_LOOPS
+ [RES_FOR ] = "FOR" ,
+ [RES_WHILE] = "WHILE",
+ [RES_UNTIL] = "UNTIL",
+ [RES_DO ] = "DO" ,
+ [RES_DONE ] = "DONE" ,
+# endif
+# if ENABLE_HUSH_LOOPS || ENABLE_HUSH_CASE
+ [RES_IN ] = "IN" ,
+# endif
+# if ENABLE_HUSH_CASE
+ [RES_CASE ] = "CASE" ,
+ [RES_CASE_IN ] = "CASE_IN" ,
+ [RES_MATCH] = "MATCH",
+ [RES_CASE_BODY] = "CASE_BODY",
+ [RES_ESAC ] = "ESAC" ,
+# endif
+ [RES_XXXX ] = "XXXX" ,
+ [RES_SNTX ] = "SNTX" ,
+ };
+ static const char *const CMDTYPE[] = {
+ "{}",
+ "()",
+ "[noglob]",
+# if ENABLE_HUSH_FUNCTIONS
+ "func()",
+# endif
+ };
+
+ int pin, prn;
+
+ pin = 0;
+ while (pi) {
+ fdprintf(2, "%*spipe %d #cmds:%d %sres_word=%s followup=%d %s\n",
+ lvl*2, "",
+ pin,
+ pi->num_cmds,
+ (IF_HAS_KEYWORDS(pi->pi_inverted ? "! " :) ""),
+ RES[pi->res_word],
+ pi->followup, PIPE[pi->followup]
+ );
+ prn = 0;
+ while (prn < pi->num_cmds) {
+ struct command *command = &pi->cmds[prn];
+ char **argv = command->argv;
+
+ fdprintf(2, "%*s cmd %d assignment_cnt:%d",
+ lvl*2, "", prn,
+ command->assignment_cnt);
+# if ENABLE_HUSH_LINENO_VAR
+ fdprintf(2, " LINENO:%u", command->lineno);
+# endif
+ if (command->group) {
+ fdprintf(2, " group %s: (argv=%p)%s%s\n",
+ CMDTYPE[command->cmd_type],
+ argv
+# if !BB_MMU
+ , " group_as_string:", command->group_as_string
+# else
+ , "", ""
+# endif
+ );
+ debug_print_tree(command->group, lvl+1);
+ prn++;
+ continue;
+ }
+ if (argv) while (*argv) {
+ fdprintf(2, " '%s'", *argv);
+ argv++;
+ }
+ if (command->redirects)
+ fdprintf(2, " {redir}");
+ fdprintf(2, "\n");
+ prn++;
+ }
+ pi = pi->next;
+ pin++;
+ }
+}
+#endif /* debug_print_tree */
+
+static struct pipe *new_pipe(void)
+{
+ struct pipe *pi;
+ pi = xzalloc(sizeof(struct pipe));
+ /*pi->res_word = RES_NONE; - RES_NONE is 0 anyway */
+ return pi;
+}
+
+/* Command (member of a pipe) is complete, or we start a new pipe
+ * if ctx->command is NULL.
+ * No errors possible here.
+ */
+static int done_command(struct parse_context *ctx)
+{
+ /* The command is really already in the pipe structure, so
+ * advance the pipe counter and make a new, null command. */
+ struct pipe *pi = ctx->pipe;
+ struct command *command = ctx->command;
+
+#if 0 /* Instead we emit error message at run time */
+ if (ctx->pending_redirect) {
+ /* For example, "cmd >" (no filename to redirect to) */
+ syntax_error("invalid redirect");
+ ctx->pending_redirect = NULL;
+ }
+#endif
+
+ if (command) {
+ if (IS_NULL_CMD(command)) {
+ debug_printf_parse("done_command: skipping null cmd, num_cmds=%d\n", pi->num_cmds);
+ goto clear_and_ret;
+ }
+ pi->num_cmds++;
+ debug_printf_parse("done_command: ++num_cmds=%d\n", pi->num_cmds);
+ //debug_print_tree(ctx->list_head, 20);
+ } else {
+ debug_printf_parse("done_command: initializing, num_cmds=%d\n", pi->num_cmds);
+ }
+
+ /* Only real trickiness here is that the uncommitted
+ * command structure is not counted in pi->num_cmds. */
+ pi->cmds = xrealloc(pi->cmds, sizeof(*pi->cmds) * (pi->num_cmds+1));
+ ctx->command = command = &pi->cmds[pi->num_cmds];
+ clear_and_ret:
+ memset(command, 0, sizeof(*command));
+#if ENABLE_HUSH_LINENO_VAR
+ command->lineno = G.parse_lineno;
+ debug_printf_parse("command->lineno = G.parse_lineno (%u)\n", G.parse_lineno);
+#endif
+ return pi->num_cmds; /* used only for 0/nonzero check */
+}
+
+static void done_pipe(struct parse_context *ctx, pipe_style type)
+{
+ int not_null;
+
+ debug_printf_parse("done_pipe entered, followup %d\n", type);
+ /* Close previous command */
+ not_null = done_command(ctx);
+#if HAS_KEYWORDS
+ ctx->pipe->pi_inverted = ctx->ctx_inverted;
+ ctx->ctx_inverted = 0;
+ ctx->pipe->res_word = ctx->ctx_res_w;
+#endif
+ if (type == PIPE_BG && ctx->list_head != ctx->pipe) {
+ /* Necessary since && and || have precedence over &:
+ * "cmd1 && cmd2 &" must spawn both cmds, not only cmd2,
+ * in a backgrounded subshell.
+ */
+ struct pipe *pi;
+ struct command *command;
+
+ /* Is this actually this construct, all pipes end with && or ||? */
+ pi = ctx->list_head;
+ while (pi != ctx->pipe) {
+ if (pi->followup != PIPE_AND && pi->followup != PIPE_OR)
+ goto no_conv;
+ pi = pi->next;
+ }
+
+ debug_printf_parse("BG with more than one pipe, converting to { p1 &&...pN; } &\n");
+ pi->followup = PIPE_SEQ; /* close pN _not_ with "&"! */
+ pi = xzalloc(sizeof(*pi));
+ pi->followup = PIPE_BG;
+ pi->num_cmds = 1;
+ pi->cmds = xzalloc(sizeof(pi->cmds[0]));
+ command = &pi->cmds[0];
+ if (CMD_NORMAL != 0) /* "if xzalloc didn't do that already" */
+ command->cmd_type = CMD_NORMAL;
+ command->group = ctx->list_head;
+#if !BB_MMU
+ command->group_as_string = xstrndup(
+ ctx->as_string.data,
+ ctx->as_string.length - 1 /* do not copy last char, "&" */
+ );
+#endif
+ /* Replace all pipes in ctx with one newly created */
+ ctx->list_head = ctx->pipe = pi;
+ /* for cases like "cmd && &", do not be tricked by last command
+ * being null - the entire {...} & is NOT null! */
+ not_null = 1;
+ } else {
+ no_conv:
+ ctx->pipe->followup = type;
+ }
+
+ /* Without this check, even just <enter> on command line generates
+ * tree of three NOPs (!). Which is harmless but annoying.
+ * IOW: it is safe to do it unconditionally. */
+ if (not_null
+#if ENABLE_HUSH_IF
+ || ctx->ctx_res_w == RES_FI
+#endif
+#if ENABLE_HUSH_LOOPS
+ || ctx->ctx_res_w == RES_DONE
+ || ctx->ctx_res_w == RES_FOR
+ || ctx->ctx_res_w == RES_IN
+#endif
+#if ENABLE_HUSH_CASE
+ || ctx->ctx_res_w == RES_ESAC
+#endif
+ ) {
+ struct pipe *new_p;
+ debug_printf_parse("done_pipe: adding new pipe: "
+ "not_null:%d ctx->ctx_res_w:%d\n",
+ not_null, ctx->ctx_res_w);
+ new_p = new_pipe();
+ ctx->pipe->next = new_p;
+ ctx->pipe = new_p;
+ /* RES_THEN, RES_DO etc are "sticky" -
+ * they remain set for pipes inside if/while.
+ * This is used to control execution.
+ * RES_FOR and RES_IN are NOT sticky (needed to support
+ * cases where variable or value happens to match a keyword):
+ */
+#if ENABLE_HUSH_LOOPS
+ if (ctx->ctx_res_w == RES_FOR
+ || ctx->ctx_res_w == RES_IN)
+ ctx->ctx_res_w = RES_NONE;
+#endif
+#if ENABLE_HUSH_CASE
+ if (ctx->ctx_res_w == RES_MATCH)
+ ctx->ctx_res_w = RES_CASE_BODY;
+ if (ctx->ctx_res_w == RES_CASE)
+ ctx->ctx_res_w = RES_CASE_IN;
+#endif
+ ctx->command = NULL; /* trick done_command below */
+ /* Create the memory for command, roughly:
+ * ctx->pipe->cmds = new struct command;
+ * ctx->command = &ctx->pipe->cmds[0];
+ */
+ done_command(ctx);
+ //debug_print_tree(ctx->list_head, 10);
+ }
+ debug_printf_parse("done_pipe return\n");
+}
+
+static void initialize_context(struct parse_context *ctx)
+{
+ memset(ctx, 0, sizeof(*ctx));
+ if (MAYBE_ASSIGNMENT != 0)
+ ctx->is_assignment = MAYBE_ASSIGNMENT;
+ ctx->pipe = ctx->list_head = new_pipe();
+ /* Create the memory for command, roughly:
+ * ctx->pipe->cmds = new struct command;
+ * ctx->command = &ctx->pipe->cmds[0];
+ */
+ done_command(ctx);
+}
+
+/* If a reserved word is found and processed, parse context is modified
+ * and 1 is returned.
+ */
+#if HAS_KEYWORDS
+struct reserved_combo {
+ char literal[6];
+ unsigned char res;
+ unsigned char assignment_flag;
+ uint32_t flag;
+};
+enum {
+ FLAG_END = (1 << RES_NONE ),
+# if ENABLE_HUSH_IF
+ FLAG_IF = (1 << RES_IF ),
+ FLAG_THEN = (1 << RES_THEN ),
+ FLAG_ELIF = (1 << RES_ELIF ),
+ FLAG_ELSE = (1 << RES_ELSE ),
+ FLAG_FI = (1 << RES_FI ),
+# endif
+# if ENABLE_HUSH_LOOPS
+ FLAG_FOR = (1 << RES_FOR ),
+ FLAG_WHILE = (1 << RES_WHILE),
+ FLAG_UNTIL = (1 << RES_UNTIL),
+ FLAG_DO = (1 << RES_DO ),
+ FLAG_DONE = (1 << RES_DONE ),
+ FLAG_IN = (1 << RES_IN ),
+# endif
+# if ENABLE_HUSH_CASE
+ FLAG_MATCH = (1 << RES_MATCH),
+ FLAG_ESAC = (1 << RES_ESAC ),
+# endif
+ FLAG_START = (1 << RES_XXXX ),
+};
+
+static const struct reserved_combo* match_reserved_word(o_string *word)
+{
+ /* Mostly a list of accepted follow-up reserved words.
+ * FLAG_END means we are done with the sequence, and are ready
+ * to turn the compound list into a command.
+ * FLAG_START means the word must start a new compound list.
+ */
+ static const struct reserved_combo reserved_list[] ALIGN4 = {
+# if ENABLE_HUSH_IF
+ { "!", RES_NONE, NOT_ASSIGNMENT , 0 },
+ { "if", RES_IF, MAYBE_ASSIGNMENT, FLAG_THEN | FLAG_START },
+ { "then", RES_THEN, MAYBE_ASSIGNMENT, FLAG_ELIF | FLAG_ELSE | FLAG_FI },
+ { "elif", RES_ELIF, MAYBE_ASSIGNMENT, FLAG_THEN },
+ { "else", RES_ELSE, MAYBE_ASSIGNMENT, FLAG_FI },
+ { "fi", RES_FI, NOT_ASSIGNMENT , FLAG_END },
+# endif
+# if ENABLE_HUSH_LOOPS
+ { "for", RES_FOR, NOT_ASSIGNMENT , FLAG_IN | FLAG_DO | FLAG_START },
+ { "while", RES_WHILE, MAYBE_ASSIGNMENT, FLAG_DO | FLAG_START },
+ { "until", RES_UNTIL, MAYBE_ASSIGNMENT, FLAG_DO | FLAG_START },
+ { "in", RES_IN, NOT_ASSIGNMENT , FLAG_DO },
+ { "do", RES_DO, MAYBE_ASSIGNMENT, FLAG_DONE },
+ { "done", RES_DONE, NOT_ASSIGNMENT , FLAG_END },
+# endif
+# if ENABLE_HUSH_CASE
+ { "case", RES_CASE, NOT_ASSIGNMENT , FLAG_MATCH | FLAG_START },
+ { "esac", RES_ESAC, NOT_ASSIGNMENT , FLAG_END },
+# endif
+ };
+ const struct reserved_combo *r;
+
+ for (r = reserved_list; r < reserved_list + ARRAY_SIZE(reserved_list); r++) {
+ if (strcmp(word->data, r->literal) == 0)
+ return r;
+ }
+ return NULL;
+}
+/* Return NULL: not a keyword, else: keyword
+ */
+static const struct reserved_combo* reserved_word(struct parse_context *ctx)
+{
+# if ENABLE_HUSH_CASE
+ static const struct reserved_combo reserved_match = {
+ "", RES_MATCH, NOT_ASSIGNMENT , FLAG_MATCH | FLAG_ESAC
+ };
+# endif
+ const struct reserved_combo *r;
+
+ if (ctx->word.has_quoted_part)
+ return 0;
+ r = match_reserved_word(&ctx->word);
+ if (!r)
+ return r; /* NULL */
+
+ debug_printf("found reserved word %s, res %d\n", r->literal, r->res);
+# if ENABLE_HUSH_CASE
+ if (r->res == RES_IN && ctx->ctx_res_w == RES_CASE_IN) {
+ /* "case word IN ..." - IN part starts first MATCH part */
+ r = &reserved_match;
+ } else
+# endif
+ if (r->flag == 0) { /* '!' */
+ if (ctx->ctx_inverted) { /* bash doesn't accept '! ! true' */
+ syntax_error("! ! command");
+ ctx->ctx_res_w = RES_SNTX;
+ }
+ ctx->ctx_inverted = 1;
+ return r;
+ }
+ if (r->flag & FLAG_START) {
+ struct parse_context *old;
+
+ old = xmemdup(ctx, sizeof(*ctx));
+ debug_printf_parse("push stack %p\n", old);
+ initialize_context(ctx);
+ ctx->stack = old;
+ } else if (/*ctx->ctx_res_w == RES_NONE ||*/ !(ctx->old_flag & (1 << r->res))) {
+ syntax_error_at(ctx->word.data);
+ ctx->ctx_res_w = RES_SNTX;
+ return r;
+ } else {
+ /* "{...} fi" is ok. "{...} if" is not
+ * Example:
+ * if { echo foo; } then { echo bar; } fi */
+ if (ctx->command->group)
+ done_pipe(ctx, PIPE_SEQ);
+ }
+
+ ctx->ctx_res_w = r->res;
+ ctx->old_flag = r->flag;
+ ctx->is_assignment = r->assignment_flag;
+ debug_printf_parse("ctx->is_assignment='%s'\n", assignment_flag[ctx->is_assignment]);
+
+ if (ctx->old_flag & FLAG_END) {
+ struct parse_context *old;
+
+ done_pipe(ctx, PIPE_SEQ);
+ debug_printf_parse("pop stack %p\n", ctx->stack);
+ old = ctx->stack;
+ old->command->group = ctx->list_head;
+ old->command->cmd_type = CMD_NORMAL;
+# if !BB_MMU
+ /* At this point, the compound command's string is in
+ * ctx->as_string... except for the leading keyword!
+ * Consider this example: "echo a | if true; then echo a; fi"
+ * ctx->as_string will contain "true; then echo a; fi",
+ * with "if " remaining in old->as_string!
+ */
+ {
+ char *str;
+ int len = old->as_string.length;
+ /* Concatenate halves */
+ o_addstr(&old->as_string, ctx->as_string.data);
+ o_free(&ctx->as_string);
+ /* Find where leading keyword starts in first half */
+ str = old->as_string.data + len;
+ if (str > old->as_string.data)
+ str--; /* skip whitespace after keyword */
+ while (str > old->as_string.data && isalpha(str[-1]))
+ str--;
+ /* Ugh, we're done with this horrid hack */
+ old->command->group_as_string = xstrdup(str);
+ debug_printf_parse("pop, remembering as:'%s'\n",
+ old->command->group_as_string);
+ }
+# endif
+ *ctx = *old; /* physical copy */
+ free(old);
+ }
+ return r;
+}
+#endif /* HAS_KEYWORDS */
+
+/* Word is complete, look at it and update parsing context.
+ * Normal return is 0. Syntax errors return 1.
+ * Note: on return, word is reset, but not o_free'd!
+ */
+static int done_word(struct parse_context *ctx)
+{
+ struct command *command = ctx->command;
+
+ debug_printf_parse("done_word entered: '%s' %p\n", ctx->word.data, command);
+ if (ctx->word.length == 0 && !ctx->word.has_quoted_part) {
+ debug_printf_parse("done_word return 0: true null, ignored\n");
+ return 0;
+ }
+
+ if (ctx->pending_redirect) {
+ /* We do not glob in e.g. >*.tmp case. bash seems to glob here
+ * only if run as "bash", not "sh" */
+ /* http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html
+ * "2.7 Redirection
+ * If the redirection operator is "<<" or "<<-", the word
+ * that follows the redirection operator shall be
+ * subjected to quote removal; it is unspecified whether
+ * any of the other expansions occur. For the other
+ * redirection operators, the word that follows the
+ * redirection operator shall be subjected to tilde
+ * expansion, parameter expansion, command substitution,
+ * arithmetic expansion, and quote removal.
+ * Pathname expansion shall not be performed
+ * on the word by a non-interactive shell; an interactive
+ * shell may perform it, but shall do so only when
+ * the expansion would result in one word."
+ */
+//bash does not do parameter/command substitution or arithmetic expansion
+//for _heredoc_ redirection word: these constructs look for exact eof marker
+// as written:
+// <<EOF$t
+// <<EOF$((1))
+// <<EOF`true` [this case also makes heredoc "quoted", a-la <<"EOF". Probably bash-4.3.43 bug]
+
+ ctx->pending_redirect->rd_filename = xstrdup(ctx->word.data);
+ /* Cater for >\file case:
+ * >\a creates file a; >\\a, >"\a", >"\\a" create file \a
+ * Same with heredocs:
+ * for <<\H delim is H; <<\\H, <<"\H", <<"\\H" - \H
+ */
+ if (ctx->pending_redirect->rd_type == REDIRECT_HEREDOC) {
+ unbackslash(ctx->pending_redirect->rd_filename);
+ /* Is it <<"HEREDOC"? */
+ if (ctx->word.has_quoted_part) {
+ ctx->pending_redirect->rd_dup |= HEREDOC_QUOTED;
+ }
+ }
+ debug_printf_parse("word stored in rd_filename: '%s'\n", ctx->word.data);
+ ctx->pending_redirect = NULL;
+ } else {
+#if HAS_KEYWORDS
+# if ENABLE_HUSH_CASE
+ if (ctx->ctx_dsemicolon
+ && strcmp(ctx->word.data, "esac") != 0 /* not "... pattern) cmd;; esac" */
+ ) {
+ /* already done when ctx_dsemicolon was set to 1: */
+ /* ctx->ctx_res_w = RES_MATCH; */
+ ctx->ctx_dsemicolon = 0;
+ } else
+# endif
+# if defined(CMD_TEST2_SINGLEWORD_NOGLOB)
+ if (command->cmd_type == CMD_TEST2_SINGLEWORD_NOGLOB
+ && strcmp(ctx->word.data, "]]") == 0
+ ) {
+ /* allow "[[ ]] >file" etc */
+ command->cmd_type = CMD_SINGLEWORD_NOGLOB;
+ } else
+# endif
+ if (!command->argv /* if it's the first word... */
+# if ENABLE_HUSH_LOOPS
+ && ctx->ctx_res_w != RES_FOR /* ...not after FOR or IN */
+ && ctx->ctx_res_w != RES_IN
+# endif
+# if ENABLE_HUSH_CASE
+ && ctx->ctx_res_w != RES_CASE
+# endif
+ ) {
+ const struct reserved_combo *reserved;
+ reserved = reserved_word(ctx);
+ debug_printf_parse("checking for reserved-ness: %d\n", !!reserved);
+ if (reserved) {
+# if ENABLE_HUSH_LINENO_VAR
+/* Case:
+ * "while ...; do
+ * cmd ..."
+ * If we don't close the pipe _now_, immediately after "do", lineno logic
+ * sees "cmd" as starting at "do" - i.e., at the previous line.
+ */
+ if (0
+ IF_HUSH_IF(|| reserved->res == RES_THEN)
+ IF_HUSH_IF(|| reserved->res == RES_ELIF)
+ IF_HUSH_IF(|| reserved->res == RES_ELSE)
+ IF_HUSH_LOOPS(|| reserved->res == RES_DO)
+ ) {
+ done_pipe(ctx, PIPE_SEQ);
+ }
+# endif
+ o_reset_to_empty_unquoted(&ctx->word);
+ debug_printf_parse("done_word return %d\n",
+ (ctx->ctx_res_w == RES_SNTX));
+ return (ctx->ctx_res_w == RES_SNTX);
+ }
+# if defined(CMD_TEST2_SINGLEWORD_NOGLOB)
+ if (strcmp(ctx->word.data, "[[") == 0) {
+ command->cmd_type = CMD_TEST2_SINGLEWORD_NOGLOB;
+ } else
+# endif
+# if defined(CMD_SINGLEWORD_NOGLOB)
+ if (0
+ /* In bash, local/export/readonly are special, args
+ * are assignments and therefore expansion of them
+ * should be "one-word" expansion:
+ * $ export i=`echo 'a b'` # one arg: "i=a b"
+ * compare with:
+ * $ ls i=`echo 'a b'` # two args: "i=a" and "b"
+ * ls: cannot access i=a: No such file or directory
+ * ls: cannot access b: No such file or directory
+ * Note: bash 3.2.33(1) does this only if export word
+ * itself is not quoted:
+ * $ export i=`echo 'aaa bbb'`; echo "$i"
+ * aaa bbb
+ * $ "export" i=`echo 'aaa bbb'`; echo "$i"
+ * aaa
+ */
+ IF_HUSH_LOCAL( || strcmp(ctx->word.data, "local") == 0)
+ IF_HUSH_EXPORT( || strcmp(ctx->word.data, "export") == 0)
+ IF_HUSH_READONLY(|| strcmp(ctx->word.data, "readonly") == 0)
+ ) {
+ command->cmd_type = CMD_SINGLEWORD_NOGLOB;
+ }
+# else
+ { /* empty block to pair "if ... else" */ }
+# endif
+ }
+#endif /* HAS_KEYWORDS */
+
+ if (command->group) {
+ /* "{ echo foo; } echo bar" - bad */
+ syntax_error_at(ctx->word.data);
+ debug_printf_parse("done_word return 1: syntax error, "
+ "groups and arglists don't mix\n");
+ return 1;
+ }
+
+ /* If this word wasn't an assignment, next ones definitely
+ * can't be assignments. Even if they look like ones. */
+ if (ctx->is_assignment != DEFINITELY_ASSIGNMENT
+ && ctx->is_assignment != WORD_IS_KEYWORD
+ ) {
+ ctx->is_assignment = NOT_ASSIGNMENT;
+ } else {
+ if (ctx->is_assignment == DEFINITELY_ASSIGNMENT) {
+ command->assignment_cnt++;
+ debug_printf_parse("++assignment_cnt=%d\n", command->assignment_cnt);
+ }
+ debug_printf_parse("ctx->is_assignment was:'%s'\n", assignment_flag[ctx->is_assignment]);
+ ctx->is_assignment = MAYBE_ASSIGNMENT;
+ }
+ debug_printf_parse("ctx->is_assignment='%s'\n", assignment_flag[ctx->is_assignment]);
+ command->argv = add_string_to_strings(command->argv, xstrdup(ctx->word.data));
+ debug_print_strings("word appended to argv", command->argv);
+ }
+
+#if ENABLE_HUSH_LOOPS
+ if (ctx->ctx_res_w == RES_FOR) {
+ if (ctx->word.has_quoted_part
+ || endofname(command->argv[0])[0] != '\0'
+ ) {
+ /* bash says just "not a valid identifier" */
+ syntax_error("bad variable name in for");
+ return 1;
+ }
+ /* Force FOR to have just one word (variable name) */
+ /* NB: basically, this makes hush see "for v in ..."
+ * syntax as if it is "for v; in ...". FOR and IN become
+ * two pipe structs in parse tree. */
+ done_pipe(ctx, PIPE_SEQ);
+ }
+#endif
+#if ENABLE_HUSH_CASE
+ /* Force CASE to have just one word */
+ if (ctx->ctx_res_w == RES_CASE) {
+ done_pipe(ctx, PIPE_SEQ);
+ }
+#endif
+
+ o_reset_to_empty_unquoted(&ctx->word);
+
+ debug_printf_parse("done_word return 0\n");
+ return 0;
+}
+
+
+/* Peek ahead in the input to find out if we have a "&n" construct,
+ * as in "2>&1", that represents duplicating a file descriptor.
+ * Return:
+ * REDIRFD_CLOSE if >&- "close fd" construct is seen,
+ * REDIRFD_SYNTAX_ERR if syntax error,
+ * REDIRFD_TO_FILE if no & was seen,
+ * or the number found.
+ */
+#if BB_MMU
+#define parse_redir_right_fd(as_string, input) \
+ parse_redir_right_fd(input)
+#endif
+static int parse_redir_right_fd(o_string *as_string, struct in_str *input)
+{
+ int ch, d, ok;
+
+ ch = i_peek(input);
+ if (ch != '&')
+ return REDIRFD_TO_FILE;
+
+ ch = i_getch(input); /* get the & */
+ nommu_addchr(as_string, ch);
+ ch = i_peek(input);
+ if (ch == '-') {
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ return REDIRFD_CLOSE;
+ }
+ d = 0;
+ ok = 0;
+ while (ch != EOF && isdigit(ch)) {
+ d = d*10 + (ch-'0');
+ ok = 1;
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ ch = i_peek(input);
+ }
+ if (ok) return d;
+
+//TODO: this is the place to catch ">&file" bashism (redirect both fd 1 and 2)
+
+ bb_simple_error_msg("ambiguous redirect");
+ return REDIRFD_SYNTAX_ERR;
+}
+
+/* Return code is 0 normal, 1 if a syntax error is detected
+ */
+static int parse_redirect(struct parse_context *ctx,
+ int fd,
+ redir_type style,
+ struct in_str *input)
+{
+ struct command *command = ctx->command;
+ struct redir_struct *redir;
+ struct redir_struct **redirp;
+ int dup_num;
+
+ dup_num = REDIRFD_TO_FILE;
+ if (style != REDIRECT_HEREDOC) {
+ /* Check for a '>&1' type redirect */
+ dup_num = parse_redir_right_fd(&ctx->as_string, input);
+ if (dup_num == REDIRFD_SYNTAX_ERR)
+ return 1;
+ } else {
+ int ch = i_peek_and_eat_bkslash_nl(input);
+ dup_num = (ch == '-'); /* HEREDOC_SKIPTABS bit is 1 */
+ if (dup_num) { /* <<-... */
+ ch = i_getch(input);
+ nommu_addchr(&ctx->as_string, ch);
+ ch = i_peek(input);
+ }
+ }
+
+ if (style == REDIRECT_OVERWRITE && dup_num == REDIRFD_TO_FILE) {
+ int ch = i_peek_and_eat_bkslash_nl(input);
+ if (ch == '|') {
+ /* >|FILE redirect ("clobbering" >).
+ * Since we do not support "set -o noclobber" yet,
+ * >| and > are the same for now. Just eat |.
+ */
+ ch = i_getch(input);
+ nommu_addchr(&ctx->as_string, ch);
+ }
+ }
+
+ /* Create a new redir_struct and append it to the linked list */
+ redirp = &command->redirects;
+ while ((redir = *redirp) != NULL) {
+ redirp = &(redir->next);
+ }
+ *redirp = redir = xzalloc(sizeof(*redir));
+ /* redir->next = NULL; */
+ /* redir->rd_filename = NULL; */
+ redir->rd_type = style;
+ redir->rd_fd = (fd == -1) ? redir_table[style].default_fd : fd;
+
+ debug_printf_parse("redirect type %d %s\n", redir->rd_fd,
+ redir_table[style].descrip);
+
+ redir->rd_dup = dup_num;
+ if (style != REDIRECT_HEREDOC && dup_num != REDIRFD_TO_FILE) {
+ /* Erik had a check here that the file descriptor in question
+ * is legit; I postpone that to "run time"
+ * A "-" representation of "close me" shows up as a -3 here */
+ debug_printf_parse("duplicating redirect '%d>&%d'\n",
+ redir->rd_fd, redir->rd_dup);
+ } else {
+#if 0 /* Instead we emit error message at run time */
+ if (ctx->pending_redirect) {
+ /* For example, "cmd > <file" */
+ syntax_error("invalid redirect");
+ }
+#endif
+ /* Set ctx->pending_redirect, so we know what to do at the
+ * end of the next parsed word. */
+ ctx->pending_redirect = redir;
+ }
+ return 0;
+}
+
+/* If a redirect is immediately preceded by a number, that number is
+ * supposed to tell which file descriptor to redirect. This routine
+ * looks for such preceding numbers. In an ideal world this routine
+ * needs to handle all the following classes of redirects...
+ * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo
+ * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo
+ * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo
+ * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo
+ *
+ * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html
+ * "2.7 Redirection
+ * ... If n is quoted, the number shall not be recognized as part of
+ * the redirection expression. For example:
+ * echo \2>a
+ * writes the character 2 into file a"
+ * We are getting it right by setting ->has_quoted_part on any \<char>
+ *
+ * A -1 return means no valid number was found,
+ * the caller should use the appropriate default for this redirection.
+ */
+static int redirect_opt_num(o_string *o)
+{
+ int num;
+
+ if (o->data == NULL)
+ return -1;
+ num = bb_strtou(o->data, NULL, 10);
+ if (errno || num < 0)
+ return -1;
+ o_reset_to_empty_unquoted(o);
+ return num;
+}
+
+#if BB_MMU
+#define fetch_till_str(as_string, input, word, skip_tabs) \
+ fetch_till_str(input, word, skip_tabs)
+#endif
+static char *fetch_till_str(o_string *as_string,
+ struct in_str *input,
+ const char *word,
+ int heredoc_flags)
+{
+ o_string heredoc = NULL_O_STRING;
+ unsigned past_EOL;
+ int prev = 0; /* not \ */
+ int ch;
+
+ /* Starting with "" is necessary for this case:
+ * cat <<EOF
+ *
+ * xxx
+ * EOF
+ */
+ heredoc.data = xzalloc(1); /* start as "", not as NULL */
+
+ goto jump_in;
+
+ while (1) {
+ ch = i_getch(input);
+ if (ch != EOF)
+ nommu_addchr(as_string, ch);
+ if (ch == '\n' || ch == EOF) {
+ check_heredoc_end:
+ if ((heredoc_flags & HEREDOC_QUOTED) || prev != '\\') {
+ /* End-of-line, and not a line continuation */
+ if (strcmp(heredoc.data + past_EOL, word) == 0) {
+ heredoc.data[past_EOL] = '\0';
+ debug_printf_heredoc("parsed '%s' heredoc '%s'\n", word, heredoc.data);
+ return heredoc.data;
+ }
+ if (ch == '\n') {
+ /* This is a new line.
+ * Remember position and backslash-escaping status.
+ */
+ o_addchr(&heredoc, ch);
+ prev = ch;
+ jump_in:
+ past_EOL = heredoc.length;
+ /* Get 1st char of next line, possibly skipping leading tabs */
+ do {
+ ch = i_getch(input);
+ if (ch != EOF)
+ nommu_addchr(as_string, ch);
+ } while ((heredoc_flags & HEREDOC_SKIPTABS) && ch == '\t');
+ /* If this immediately ended the line,
+ * go back to end-of-line checks.
+ */
+ if (ch == '\n')
+ goto check_heredoc_end;
+ }
+ } else {
+ /* Backslash-line continuation in an unquoted
+ * heredoc. This does not need special handling
+ * for heredoc body (unquoted heredocs are
+ * expanded on "execution" and that would take
+ * care of this case too), but not the case
+ * of line continuation *in terminator*:
+ * cat <<EOF
+ * Ok1
+ * EO\
+ * F
+ */
+ heredoc.data[--heredoc.length] = '\0';
+ prev = 0; /* not '\' */
+ continue;
+ }
+ }
+ if (ch == EOF) {
+ o_free(&heredoc);
+ return NULL; /* error */
+ }
+ o_addchr(&heredoc, ch);
+ nommu_addchr(as_string, ch);
+ if (prev == '\\' && ch == '\\')
+ /* Correctly handle foo\\<eol> (not a line cont.) */
+ prev = 0; /* not '\' */
+ else
+ prev = ch;
+ }
+}
+
+/* Look at entire parse tree for not-yet-loaded REDIRECT_HEREDOCs
+ * and load them all. There should be exactly heredoc_cnt of them.
+ */
+#if BB_MMU
+#define fetch_heredocs(as_string, pi, heredoc_cnt, input) \
+ fetch_heredocs(pi, heredoc_cnt, input)
+#endif
+static int fetch_heredocs(o_string *as_string, struct pipe *pi, int heredoc_cnt, struct in_str *input)
+{
+ while (pi && heredoc_cnt) {
+ int i;
+ struct command *cmd = pi->cmds;
+
+ debug_printf_heredoc("fetch_heredocs: num_cmds:%d cmd argv0:'%s'\n",
+ pi->num_cmds,
+ cmd->argv ? cmd->argv[0] : "NONE"
+ );
+ for (i = 0; i < pi->num_cmds; i++) {
+ struct redir_struct *redir = cmd->redirects;
+
+ debug_printf_heredoc("fetch_heredocs: %d cmd argv0:'%s'\n",
+ i, cmd->argv ? cmd->argv[0] : "NONE");
+ while (redir) {
+ if (redir->rd_type == REDIRECT_HEREDOC) {
+ char *p;
+
+ redir->rd_type = REDIRECT_HEREDOC2;
+ /* redir->rd_dup is (ab)used to indicate <<- */
+ p = fetch_till_str(as_string, input,
+ redir->rd_filename, redir->rd_dup);
+ if (!p) {
+ syntax_error("unexpected EOF in here document");
+ return -1;
+ }
+ free(redir->rd_filename);
+ redir->rd_filename = p;
+ heredoc_cnt--;
+ }
+ redir = redir->next;
+ }
+ if (cmd->group) {
+ //bb_error_msg("%s:%u heredoc_cnt:%d", __func__, __LINE__, heredoc_cnt);
+ heredoc_cnt = fetch_heredocs(as_string, cmd->group, heredoc_cnt, input);
+ //bb_error_msg("%s:%u heredoc_cnt:%d", __func__, __LINE__, heredoc_cnt);
+ if (heredoc_cnt < 0)
+ return heredoc_cnt; /* error */
+ }
+ cmd++;
+ }
+ pi = pi->next;
+ }
+ return heredoc_cnt;
+}
+
+
+static int run_list(struct pipe *pi);
+#if BB_MMU
+#define parse_stream(pstring, heredoc_cnt_ptr, input, end_trigger) \
+ parse_stream(heredoc_cnt_ptr, input, end_trigger)
+#endif
+static struct pipe *parse_stream(char **pstring,
+ int *heredoc_cnt_ptr,
+ struct in_str *input,
+ int end_trigger);
+
+/* Returns number of heredocs not yet consumed,
+ * or -1 on error.
+ */
+static int parse_group(struct parse_context *ctx,
+ struct in_str *input, int ch)
+{
+ /* ctx->word contains characters seen prior to ( or {.
+ * Typically it's empty, but for function defs,
+ * it contains function name (without '()'). */
+#if BB_MMU
+# define as_string NULL
+#else
+ char *as_string = NULL;
+#endif
+ struct pipe *pipe_list;
+ int heredoc_cnt = 0;
+ int endch;
+ struct command *command = ctx->command;
+
+ debug_printf_parse("parse_group entered\n");
+#if ENABLE_HUSH_FUNCTIONS
+ if (ch == '(' && !ctx->word.has_quoted_part) {
+ if (ctx->word.length)
+ if (done_word(ctx))
+ return -1;
+ if (!command->argv)
+ goto skip; /* (... */
+ if (command->argv[1]) { /* word word ... (... */
+ syntax_error_unexpected_ch('(');
+ return -1;
+ }
+ /* it is "word(..." or "word (..." */
+ do
+ ch = i_getch(input);
+ while (ch == ' ' || ch == '\t');
+ if (ch != ')') {
+ syntax_error_unexpected_ch(ch);
+ return -1;
+ }
+ nommu_addchr(&ctx->as_string, ch);
+ do
+ ch = i_getch(input);
+ while (ch == ' ' || ch == '\t' || ch == '\n');
+ if (ch != '{' && ch != '(') {
+ syntax_error_unexpected_ch(ch);
+ return -1;
+ }
+ nommu_addchr(&ctx->as_string, ch);
+ command->cmd_type = CMD_FUNCDEF;
+ goto skip;
+ }
+#endif
+
+#if 0 /* Prevented by caller */
+ if (command->argv /* word [word]{... */
+ || ctx->word.length /* word{... */
+ || ctx->word.has_quoted_part /* ""{... */
+ ) {
+ syntax_error(NULL);
+ debug_printf_parse("parse_group return -1: "
+ "syntax error, groups and arglists don't mix\n");
+ return -1;
+ }
+#endif
+
+ IF_HUSH_FUNCTIONS(skip:)
+
+ endch = '}';
+ if (ch == '(') {
+ endch = ')';
+ IF_HUSH_FUNCTIONS(if (command->cmd_type != CMD_FUNCDEF))
+ command->cmd_type = CMD_SUBSHELL;
+ } else {
+ /* bash does not allow "{echo...", requires whitespace */
+ ch = i_peek(input);
+ if (ch != ' ' && ch != '\t' && ch != '\n'
+ && ch != '(' /* but "{(..." is allowed (without whitespace) */
+ ) {
+ syntax_error_unexpected_ch(ch);
+ return -1;
+ }
+ if (ch != '(') {
+ ch = i_getch(input);
+ nommu_addchr(&ctx->as_string, ch);
+ }
+ }
+
+ debug_printf_heredoc("calling parse_stream, heredoc_cnt:%d\n", heredoc_cnt);
+ pipe_list = parse_stream(&as_string, &heredoc_cnt, input, endch);
+ debug_printf_heredoc("parse_stream returned: heredoc_cnt:%d\n", heredoc_cnt);
+#if !BB_MMU
+ if (as_string)
+ o_addstr(&ctx->as_string, as_string);
+#endif
+
+ /* empty ()/{} or parse error? */
+ if (!pipe_list || pipe_list == ERR_PTR) {
+ /* parse_stream already emitted error msg */
+ if (!BB_MMU)
+ free(as_string);
+ debug_printf_parse("parse_group return -1: "
+ "parse_stream returned %p\n", pipe_list);
+ return -1;
+ }
+#if !BB_MMU
+ as_string[strlen(as_string) - 1] = '\0'; /* plink ')' or '}' */
+ command->group_as_string = as_string;
+ debug_printf_parse("end of group, remembering as:'%s'\n",
+ command->group_as_string);
+#endif
+
+#if ENABLE_HUSH_FUNCTIONS
+ /* Convert "f() (cmds)" to "f() {(cmds)}" */
+ if (command->cmd_type == CMD_FUNCDEF && endch == ')') {
+ struct command *cmd2;
+
+ cmd2 = xzalloc(sizeof(*cmd2));
+ cmd2->cmd_type = CMD_SUBSHELL;
+ cmd2->group = pipe_list;
+# if !BB_MMU
+//UNTESTED!
+ cmd2->group_as_string = command->group_as_string;
+ command->group_as_string = xasprintf("(%s)", command->group_as_string);
+# endif
+
+ pipe_list = new_pipe();
+ pipe_list->cmds = cmd2;
+ pipe_list->num_cmds = 1;
+ }
+#endif
+
+ command->group = pipe_list;
+
+ debug_printf_parse("parse_group return %d\n", heredoc_cnt);
+ return heredoc_cnt;
+ /* command remains "open", available for possible redirects */
+#undef as_string
+}
+
+#if ENABLE_HUSH_TICK || ENABLE_FEATURE_SH_MATH || ENABLE_HUSH_DOLLAR_OPS
+/* Subroutines for copying $(...) and `...` things */
+/* '...' */
+static int add_till_single_quote(o_string *dest, struct in_str *input)
+{
+ while (1) {
+ int ch = i_getch(input);
+ if (ch == EOF) {
+ syntax_error_unterm_ch('\'');
+ return 0;
+ }
+ if (ch == '\'')
+ return 1;
+ o_addchr(dest, ch);
+ }
+}
+static int add_till_single_quote_dquoted(o_string *dest, struct in_str *input)
+{
+ while (1) {
+ int ch = i_getch(input);
+ if (ch == EOF) {
+ syntax_error_unterm_ch('\'');
+ return 0;
+ }
+ if (ch == '\'')
+ return 1;
+ o_addqchr(dest, ch);
+ }
+}
+/* "...\"...`..`...." - do we need to handle "...$(..)..." too? */
+static int add_till_backquote(o_string *dest, struct in_str *input, int in_dquote);
+static int add_till_double_quote(o_string *dest, struct in_str *input)
+{
+ while (1) {
+ int ch = i_getch(input);
+ if (ch == EOF) {
+ syntax_error_unterm_ch('"');
+ return 0;
+ }
+ if (ch == '"')
+ return 1;
+ if (ch == '\\') { /* \x. Copy both chars. */
+ o_addchr(dest, ch);
+ ch = i_getch(input);
+ }
+ o_addchr(dest, ch);
+ if (ch == '`') {
+ if (!add_till_backquote(dest, input, /*in_dquote:*/ 1))
+ return 0;
+ o_addchr(dest, ch);
+ continue;
+ }
+ //if (ch == '$') ...
+ }
+}
+/* Process `cmd` - copy contents until "`" is seen. Complicated by
+ * \` quoting.
+ * "Within the backquoted style of command substitution, backslash
+ * shall retain its literal meaning, except when followed by: '$', '`', or '\'.
+ * The search for the matching backquote shall be satisfied by the first
+ * backquote found without a preceding backslash; during this search,
+ * if a non-escaped backquote is encountered within a shell comment,
+ * a here-document, an embedded command substitution of the $(command)
+ * form, or a quoted string, undefined results occur. A single-quoted
+ * or double-quoted string that begins, but does not end, within the
+ * "`...`" sequence produces undefined results."
+ * Example Output
+ * echo `echo '\'TEST\`echo ZZ\`BEST` \TESTZZBEST
+ */
+static int add_till_backquote(o_string *dest, struct in_str *input, int in_dquote)
+{
+ while (1) {
+ int ch = i_getch(input);
+ if (ch == '`')
+ return 1;
+ if (ch == '\\') {
+ /* \x. Copy both unless it is \`, \$, \\ and maybe \" */
+ ch = i_getch(input);
+ if (ch != '`'
+ && ch != '$'
+ && ch != '\\'
+ && (!in_dquote || ch != '"')
+ ) {
+ o_addchr(dest, '\\');
+ }
+ }
+ if (ch == EOF) {
+ syntax_error_unterm_ch('`');
+ return 0;
+ }
+ o_addchr(dest, ch);
+ }
+}
+/* Process $(cmd) - copy contents until ")" is seen. Complicated by
+ * quoting and nested ()s.
+ * "With the $(command) style of command substitution, all characters
+ * following the open parenthesis to the matching closing parenthesis
+ * constitute the command. Any valid shell script can be used for command,
+ * except a script consisting solely of redirections which produces
+ * unspecified results."
+ * Example Output
+ * echo $(echo '(TEST)' BEST) (TEST) BEST
+ * echo $(echo 'TEST)' BEST) TEST) BEST
+ * echo $(echo \(\(TEST\) BEST) ((TEST) BEST
+ *
+ * Also adapted to eat ${var%...} and $((...)) constructs, since ... part
+ * can contain arbitrary constructs, just like $(cmd).
+ * In bash compat mode, it needs to also be able to stop on ':' or '/'
+ * for ${var:N[:M]} and ${var/P[/R]} parsing.
+ */
+#define DOUBLE_CLOSE_CHAR_FLAG 0x80
+static int add_till_closing_bracket(o_string *dest, struct in_str *input, unsigned end_ch)
+{
+ int ch;
+ char dbl = end_ch & DOUBLE_CLOSE_CHAR_FLAG;
+# if BASH_SUBSTR || BASH_PATTERN_SUBST
+ char end_char2 = end_ch >> 8;
+# endif
+ end_ch &= (DOUBLE_CLOSE_CHAR_FLAG - 1);
+
+# if ENABLE_HUSH_INTERACTIVE
+ G.promptmode = 1; /* PS2 */
+# endif
+ debug_printf_prompt("%s promptmode=%d\n", __func__, G.promptmode);
+
+ while (1) {
+ ch = i_getch(input);
+ if (ch == EOF) {
+ syntax_error_unterm_ch(end_ch);
+ return 0;
+ }
+ if (ch == end_ch
+# if BASH_SUBSTR || BASH_PATTERN_SUBST
+ || ch == end_char2
+# endif
+ ) {
+ if (!dbl)
+ break;
+ /* we look for closing )) of $((EXPR)) */
+ if (i_peek_and_eat_bkslash_nl(input) == end_ch) {
+ i_getch(input); /* eat second ')' */
+ break;
+ }
+ }
+ o_addchr(dest, ch);
+ //bb_error_msg("%s:o_addchr('%c')", __func__, ch);
+ if (ch == '(' || ch == '{') {
+ ch = (ch == '(' ? ')' : '}');
+ if (!add_till_closing_bracket(dest, input, ch))
+ return 0;
+ o_addchr(dest, ch);
+ continue;
+ }
+ if (ch == '\'') {
+ if (!add_till_single_quote(dest, input))
+ return 0;
+ o_addchr(dest, ch);
+ continue;
+ }
+ if (ch == '"') {
+ if (!add_till_double_quote(dest, input))
+ return 0;
+ o_addchr(dest, ch);
+ continue;
+ }
+ if (ch == '`') {
+ if (!add_till_backquote(dest, input, /*in_dquote:*/ 0))
+ return 0;
+ o_addchr(dest, ch);
+ continue;
+ }
+ if (ch == '\\') {
+ /* \x. Copy verbatim. Important for \(, \) */
+ ch = i_getch(input);
+ if (ch == EOF) {
+ syntax_error_unterm_ch(end_ch);
+ return 0;
+ }
+# if 0
+ if (ch == '\n') {
+ /* "backslash+newline", ignore both */
+ o_delchr(dest); /* undo insertion of '\' */
+ continue;
+ }
+# endif
+ o_addchr(dest, ch);
+ //bb_error_msg("%s:o_addchr('%c') after '\\'", __func__, ch);
+ continue;
+ }
+ }
+ debug_printf_parse("%s return '%s' ch:'%c'\n", __func__, dest->data, ch);
+ return ch;
+}
+#endif /* ENABLE_HUSH_TICK || ENABLE_FEATURE_SH_MATH || ENABLE_HUSH_DOLLAR_OPS */
+
+#if BASH_DOLLAR_SQUOTE
+/* Return code: 1 for "found and parsed", 0 for "seen something else" */
+# if BB_MMU
+#define parse_dollar_squote(as_string, dest, input) \
+ parse_dollar_squote(dest, input)
+#define as_string NULL
+# endif
+static int parse_dollar_squote(o_string *as_string, o_string *dest, struct in_str *input)
+{
+ int start;
+ int ch = i_peek_and_eat_bkslash_nl(input); /* first character after the $ */
+ debug_printf_parse("parse_dollar_squote entered: ch='%c'\n", ch);
+ if (ch != '\'')
+ return 0;
+
+ dest->has_quoted_part = 1;
+ start = dest->length;
+
+ ch = i_getch(input); /* eat ' */
+ nommu_addchr(as_string, ch);
+ while (1) {
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ if (ch == EOF) {
+ syntax_error_unterm_ch('\'');
+ return 0;
+ }
+ if (ch == '\'')
+ break;
+ if (ch == SPECIAL_VAR_SYMBOL) {
+ /* Convert raw ^C to corresponding special variable reference */
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ o_addchr(dest, SPECIAL_VAR_QUOTED_SVS);
+ /* will addchr() another SPECIAL_VAR_SYMBOL (see after the if() block) */
+ } else if (ch == '\\') {
+ static const char C_escapes[] ALIGN1 = "nrbtfav""x\\01234567";
+
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ if (strchr(C_escapes, ch)) {
+ char buf[4];
+ char *p = buf;
+ int cnt = 2;
+
+ buf[0] = ch;
+ if ((unsigned char)(ch - '0') <= 7) { /* \ooo */
+ do {
+ ch = i_peek(input);
+ if ((unsigned char)(ch - '0') > 7)
+ break;
+ *++p = ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ } while (--cnt != 0);
+ } else if (ch == 'x') { /* \xHH */
+ do {
+ ch = i_peek(input);
+ if (!isxdigit(ch))
+ break;
+ *++p = ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ } while (--cnt != 0);
+ if (cnt == 2) { /* \x but next char is "bad" */
+ ch = 'x';
+ goto unrecognized;
+ }
+ } /* else simple seq like \\ or \t */
+ *++p = '\0';
+ p = buf;
+ ch = bb_process_escape_sequence((void*)&p);
+ //bb_error_msg("buf:'%s' ch:%x", buf, ch);
+ if (ch == '\0')
+ continue; /* bash compat: $'...\0...' emits nothing */
+ } else { /* unrecognized "\z": encode both chars unless ' or " */
+ if (ch != '\'' && ch != '"') {
+ unrecognized:
+ o_addqchr(dest, '\\');
+ }
+ }
+ } /* if (\...) */
+ o_addqchr(dest, ch);
+ }
+
+ if (dest->length == start) {
+ /* $'', $'\0', $'\000\x00' and the like */
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ }
+
+ return 1;
+# undef as_string
+}
+#else
+# #define parse_dollar_squote(as_string, dest, input) 0
+#endif /* BASH_DOLLAR_SQUOTE */
+
+/* Return code: 0 for OK, 1 for syntax error */
+#if BB_MMU
+#define parse_dollar(as_string, dest, input, quote_mask) \
+ parse_dollar(dest, input, quote_mask)
+#define as_string NULL
+#endif
+static int parse_dollar(o_string *as_string,
+ o_string *dest,
+ struct in_str *input, unsigned char quote_mask)
+{
+ int ch = i_peek_and_eat_bkslash_nl(input); /* first character after the $ */
+
+ debug_printf_parse("parse_dollar entered: ch='%c' quote_mask:0x%x\n", ch, quote_mask);
+ if (isalpha(ch)) {
+ make_var:
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ /*make_var1:*/
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ while (1) {
+ debug_printf_parse(": '%c'\n", ch);
+ o_addchr(dest, ch | quote_mask);
+ quote_mask = 0;
+ ch = i_peek_and_eat_bkslash_nl(input);
+ if (!isalnum(ch) && ch != '_') {
+ /* End of variable name reached */
+ break;
+ }
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ }
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ } else if (isdigit(ch)) {
+ make_one_char_var:
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ debug_printf_parse(": '%c'\n", ch);
+ o_addchr(dest, ch | quote_mask);
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ } else switch (ch) {
+ case '$': /* pid */
+ case '!': /* last bg pid */
+ case '?': /* last exit code */
+ case '#': /* number of args */
+ case '*': /* args */
+ case '@': /* args */
+ case '-': /* $- option flags set by set builtin or shell options (-i etc) */
+ goto make_one_char_var;
+ case '{': {
+ char len_single_ch;
+
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+
+ ch = i_getch(input); /* eat '{' */
+ nommu_addchr(as_string, ch);
+
+ ch = i_getch_and_eat_bkslash_nl(input); /* first char after '{' */
+ /* It should be ${?}, or ${#var},
+ * or even ${?+subst} - operator acting on a special variable,
+ * or the beginning of variable name.
+ */
+ if (ch == EOF
+ || (!strchr(_SPECIAL_VARS_STR, ch) && !isalnum(ch)) /* not one of those */
+ ) {
+ bad_dollar_syntax:
+ syntax_error_unterm_str("${name}");
+ debug_printf_parse("parse_dollar return 0: unterminated ${name}\n");
+ return 0;
+ }
+ nommu_addchr(as_string, ch);
+ len_single_ch = ch;
+ ch |= quote_mask;
+
+ /* It's possible to just call add_till_closing_bracket() at this point.
+ * However, this regresses some of our testsuite cases
+ * which check invalid constructs like ${%}.
+ * Oh well... let's check that the var name part is fine... */
+
+ if (isdigit(len_single_ch)
+ || (len_single_ch == '#' && isdigit(i_peek_and_eat_bkslash_nl(input)))
+ ) {
+ /* Execution engine uses plain xatoi_positive()
+ * to interpret ${NNN} and {#NNN},
+ * check syntax here in the parser.
+ * (bash does not support expressions in ${#NN},
+ * e.g. ${#$var} and {#1:+WORD} are not supported).
+ */
+ unsigned cnt = 9; /* max 9 digits for ${NN} and 8 for {#NN} */
+ while (1) {
+ o_addchr(dest, ch);
+ debug_printf_parse(": '%c'\n", ch);
+ ch = i_getch_and_eat_bkslash_nl(input);
+ nommu_addchr(as_string, ch);
+ if (ch == '}')
+ break;
+ if (--cnt == 0)
+ goto bad_dollar_syntax;
+ if (len_single_ch != '#' && strchr(VAR_SUBST_OPS, ch))
+ /* ${NN<op>...} is valid */
+ goto eat_until_closing;
+ if (!isdigit(ch))
+ goto bad_dollar_syntax;
+ }
+ } else
+ while (1) {
+ unsigned pos;
+
+ o_addchr(dest, ch);
+ debug_printf_parse(": '%c'\n", ch);
+
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ if (ch == '}')
+ break;
+ if (!isalnum(ch) && ch != '_') {
+ unsigned end_ch;
+ unsigned char last_ch;
+ /* handle parameter expansions
+ * http://www.opengroup.org/onlinepubs/009695399/utilities/xcu_chap02.html#tag_02_06_02
+ */
+ if (!strchr(VAR_SUBST_OPS, ch)) { /* ${var<bad_char>... */
+ if (len_single_ch != '#'
+ /*|| !strchr(SPECIAL_VARS_STR, ch) - disallow errors like ${#+} ? */
+ || i_peek(input) != '}'
+ ) {
+ goto bad_dollar_syntax;
+ }
+ /* else: it's "length of C" ${#C} op,
+ * where C is a single char
+ * special var name, e.g. ${#!}.
+ */
+ }
+ eat_until_closing:
+ /* Eat everything until closing '}' (or ':') */
+ end_ch = '}';
+ if (BASH_SUBSTR
+ && ch == ':'
+ && !strchr(MINUS_PLUS_EQUAL_QUESTION, i_peek(input))
+ ) {
+ /* It's ${var:N[:M]} thing */
+ end_ch = '}' * 0x100 + ':';
+ }
+ if (BASH_PATTERN_SUBST
+ && ch == '/'
+ ) {
+ /* It's ${var/[/]pattern[/repl]} thing */
+ if (i_peek(input) == '/') { /* ${var//pattern[/repl]}? */
+ i_getch(input);
+ nommu_addchr(as_string, '/');
+ ch = '\\';
+ }
+ end_ch = '}' * 0x100 + '/';
+ }
+ o_addchr(dest, ch);
+ /* The pattern can't be empty.
+ * IOW: if the first char after "${v//" is a slash,
+ * it does not terminate the pattern - it's the first char of the pattern:
+ * v=/dev/ram; echo ${v////-} prints -dev-ram (pattern is "/")
+ * v=/dev/ram; echo ${v///r/-} prints /dev-am (pattern is "/r")
+ */
+ if (i_peek(input) == '/') {
+ o_addchr(dest, i_getch(input));
+ }
+ again:
+ if (!BB_MMU)
+ pos = dest->length;
+#if ENABLE_HUSH_DOLLAR_OPS
+ last_ch = add_till_closing_bracket(dest, input, end_ch);
+ if (last_ch == 0) /* error? */
+ return 0;
+#else
+# error Simple code to only allow ${var} is not implemented
+#endif
+ if (as_string) {
+ o_addstr(as_string, dest->data + pos);
+ o_addchr(as_string, last_ch);
+ }
+
+ if ((BASH_SUBSTR || BASH_PATTERN_SUBST)
+ && (end_ch & 0xff00)
+ ) {
+ /* close the first block: */
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ /* while parsing N from ${var:N[:M]}
+ * or pattern from ${var/[/]pattern[/repl]} */
+ if ((end_ch & 0xff) == last_ch) {
+ /* got ':' or '/'- parse the rest */
+ end_ch = '}';
+ goto again;
+ }
+ /* got '}' */
+ if (BASH_SUBSTR && end_ch == '}' * 0x100 + ':') {
+ /* it's ${var:N} - emulate :999999999 */
+ o_addstr(dest, "999999999");
+ } /* else: it's ${var/[/]pattern} */
+ }
+ break;
+ }
+ len_single_ch = 0; /* it can't be ${#C} op */
+ }
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ break;
+ }
+#if ENABLE_FEATURE_SH_MATH || ENABLE_HUSH_TICK
+ case '(': {
+ unsigned pos;
+
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+# if ENABLE_FEATURE_SH_MATH
+ if (i_peek_and_eat_bkslash_nl(input) == '(') {
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ o_addchr(dest, quote_mask | '+');
+ if (!BB_MMU)
+ pos = dest->length;
+ if (!add_till_closing_bracket(dest, input, ')' | DOUBLE_CLOSE_CHAR_FLAG))
+ return 0; /* error */
+ if (as_string) {
+ o_addstr(as_string, dest->data + pos);
+ o_addchr(as_string, ')');
+ o_addchr(as_string, ')');
+ }
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ break;
+ }
+# endif
+# if ENABLE_HUSH_TICK
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ o_addchr(dest, quote_mask | '`');
+ if (!BB_MMU)
+ pos = dest->length;
+ if (!add_till_closing_bracket(dest, input, ')'))
+ return 0; /* error */
+ if (as_string) {
+ o_addstr(as_string, dest->data + pos);
+ o_addchr(as_string, ')');
+ }
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+# endif
+ break;
+ }
+#endif
+ case '_':
+ goto make_var;
+#if 0
+ /* TODO: $_: */
+ /* $_ Shell or shell script name; or last argument of last command
+ * (if last command wasn't a pipe; if it was, bash sets $_ to "");
+ * but in command's env, set to full pathname used to invoke it */
+ ch = i_getch(input);
+ nommu_addchr(as_string, ch);
+ ch = i_peek_and_eat_bkslash_nl(input);
+ if (isalnum(ch)) { /* it's $_name or $_123 */
+ ch = '_';
+ goto make_var1;
+ }
+ /* else: it's $_ */
+#endif
+ default:
+ o_addQchr(dest, '$');
+ }
+ debug_printf_parse("parse_dollar return 1 (ok)\n");
+ return 1;
+#undef as_string
+}
+
+#if BB_MMU
+#define encode_string(as_string, dest, input, dquote_end) \
+ encode_string(dest, input, dquote_end)
+#define as_string NULL
+#endif
+static int encode_string(o_string *as_string,
+ o_string *dest,
+ struct in_str *input,
+ int dquote_end)
+{
+ int ch;
+ int next;
+
+ again:
+ ch = i_getch(input);
+ if (ch != EOF)
+ nommu_addchr(as_string, ch);
+ if (ch == dquote_end) { /* may be only '"' or EOF */
+ debug_printf_parse("encode_string return 1 (ok)\n");
+ return 1;
+ }
+ /* note: can't move it above ch == dquote_end check! */
+ if (ch == EOF) {
+ syntax_error_unterm_ch('"');
+ return 0; /* error */
+ }
+ next = '\0';
+ if (ch != '\n') {
+ next = i_peek(input);
+ }
+ debug_printf_parse("\" ch=%c (%d) escape=%d\n",
+ ch, ch, !!(dest->o_expflags & EXP_FLAG_ESC_GLOB_CHARS));
+ if (ch == '\\') {
+ if (next == EOF) {
+ /* Testcase: in interactive shell a file with
+ * echo "unterminated string\<eof>
+ * is sourced.
+ */
+ syntax_error_unterm_ch('"');
+ return 0; /* error */
+ }
+ /* bash:
+ * "The backslash retains its special meaning [in "..."]
+ * only when followed by one of the following characters:
+ * $, `, ", \, or <newline>. A double quote may be quoted
+ * within double quotes by preceding it with a backslash."
+ * NB: in (unquoted) heredoc, above does not apply to ",
+ * therefore we check for it by "next == dquote_end" cond.
+ */
+ if (next == dquote_end || strchr("$`\\\n", next)) {
+ ch = i_getch(input); /* eat next */
+ if (ch == '\n')
+ goto again; /* skip \<newline> */
+ } /* else: ch remains == '\\', and we double it below: */
+ o_addqchr(dest, ch); /* \c if c is a glob char, else just c */
+ nommu_addchr(as_string, ch);
+ goto again;
+ }
+ if (ch == '$') {
+ //if (parse_dollar_squote(as_string, dest, input))
+ // goto again;
+ if (!parse_dollar(as_string, dest, input, /*quote_mask:*/ 0x80)) {
+ debug_printf_parse("encode_string return 0: "
+ "parse_dollar returned 0 (error)\n");
+ return 0;
+ }
+ goto again;
+ }
+#if ENABLE_HUSH_TICK
+ if (ch == '`') {
+ //unsigned pos = dest->length;
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ o_addchr(dest, 0x80 | '`');
+ if (!add_till_backquote(dest, input, /*in_dquote:*/ dquote_end == '"'))
+ return 0; /* error */
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ //debug_printf_subst("SUBST RES3 '%s'\n", dest->data + pos);
+ goto again;
+ }
+#endif
+ o_addQchr(dest, ch);
+ if (ch == SPECIAL_VAR_SYMBOL) {
+ /* Convert "^C" to corresponding special variable reference */
+ o_addchr(dest, SPECIAL_VAR_QUOTED_SVS);
+ o_addchr(dest, SPECIAL_VAR_SYMBOL);
+ }
+ goto again;
+#undef as_string
+}
+
+/*
+ * Scan input until EOF or end_trigger char.
+ * Return a list of pipes to execute, or NULL on EOF
+ * or if end_trigger character is met.
+ * On syntax error, exit if shell is not interactive,
+ * reset parsing machinery and start parsing anew,
+ * or return ERR_PTR.
+ */
+static struct pipe *parse_stream(char **pstring,
+ int *heredoc_cnt_ptr,
+ struct in_str *input,
+ int end_trigger)
+{
+ struct parse_context ctx;
+ int heredoc_cnt;
+
+ /* Single-quote triggers a bypass of the main loop until its mate is
+ * found. When recursing, quote state is passed in via ctx.word.o_expflags.
+ */
+ debug_printf_parse("parse_stream entered, end_trigger='%c'\n",
+ end_trigger ? end_trigger : 'X');
+ debug_enter();
+
+ initialize_context(&ctx);
+
+ /* If very first arg is "" or '', ctx.word.data may end up NULL.
+ * Preventing this:
+ */
+ ctx.word.data = xzalloc(1); /* start as "", not as NULL */
+
+ /* We used to separate words on $IFS here. This was wrong.
+ * $IFS is used only for word splitting when $var is expanded,
+ * here we should use blank chars as separators, not $IFS
+ */
+
+ heredoc_cnt = 0;
+ while (1) {
+ const char *is_blank;
+ const char *is_special;
+ int ch;
+ int next;
+ int redir_fd;
+ redir_type redir_style;
+
+ ch = i_getch(input);
+ debug_printf_parse(": ch=%c (%d) escape=%d\n",
+ ch, ch, !!(ctx.word.o_expflags & EXP_FLAG_ESC_GLOB_CHARS));
+ if (ch == EOF) {
+ struct pipe *pi;
+
+ if (heredoc_cnt) {
+ syntax_error_unterm_str("here document");
+ goto parse_error_exitcode1;
+ }
+ if (end_trigger == ')') {
+ syntax_error_unterm_ch('(');
+ goto parse_error_exitcode1;
+ }
+ if (end_trigger == '}') {
+ syntax_error_unterm_ch('{');
+ goto parse_error_exitcode1;
+ }
+
+ if (done_word(&ctx)) {
+ goto parse_error_exitcode1;
+ }
+ o_free_and_set_NULL(&ctx.word);
+ done_pipe(&ctx, PIPE_SEQ);
+ pi = ctx.list_head;
+ /* If we got nothing... */
+ /* (this makes bare "&" cmd a no-op.
+ * bash says: "syntax error near unexpected token '&'") */
+ if (pi->num_cmds == 0
+ IF_HAS_KEYWORDS(&& pi->res_word == RES_NONE)
+ ) {
+ free_pipe_list(pi);
+ pi = NULL;
+ }
+#if !BB_MMU
+ debug_printf_parse("as_string1 '%s'\n", ctx.as_string.data);
+ if (pstring)
+ *pstring = ctx.as_string.data;
+ else
+ o_free(&ctx.as_string);
+#endif
+ // heredoc_cnt must be 0 here anyway
+ //if (heredoc_cnt_ptr)
+ // *heredoc_cnt_ptr = heredoc_cnt;
+ debug_leave();
+ debug_printf_heredoc("parse_stream return heredoc_cnt:%d\n", heredoc_cnt);
+ debug_printf_parse("parse_stream return %p\n", pi);
+ return pi;
+ }
+
+ /* Handle "'" and "\" first, as they won't play nice with
+ * i_peek_and_eat_bkslash_nl() anyway:
+ * echo z\\
+ * and
+ * echo '\
+ * '
+ * would break.
+ */
+ if (ch == '\\') {
+ ch = i_getch(input);
+ if (ch == '\n')
+ continue; /* drop \<newline>, get next char */
+ nommu_addchr(&ctx.as_string, '\\');
+ if (ch == SPECIAL_VAR_SYMBOL) {
+ nommu_addchr(&ctx.as_string, ch);
+ /* Convert \^C to corresponding special variable reference */
+ goto case_SPECIAL_VAR_SYMBOL;
+ }
+ o_addchr(&ctx.word, '\\');
+ if (ch == EOF) {
+ /* Testcase: eval 'echo Ok\' */
+ /* bash-4.3.43 was removing backslash,
+ * but 4.4.19 retains it, most other shells too
+ */
+ continue; /* get next char */
+ }
+ /* Example: echo Hello \2>file
+ * we need to know that word 2 is quoted
+ */
+ ctx.word.has_quoted_part = 1;
+ nommu_addchr(&ctx.as_string, ch);
+ o_addchr(&ctx.word, ch);
+ continue; /* get next char */
+ }
+ nommu_addchr(&ctx.as_string, ch);
+ if (ch == '\'') {
+ ctx.word.has_quoted_part = 1;
+ next = i_getch(input);
+ if (next == '\'' && !ctx.pending_redirect)
+ goto insert_empty_quoted_str_marker;
+
+ ch = next;
+ while (1) {
+ if (ch == EOF) {
+ syntax_error_unterm_ch('\'');
+ goto parse_error_exitcode1;
+ }
+ nommu_addchr(&ctx.as_string, ch);
+ if (ch == '\'')
+ break;
+ if (ch == SPECIAL_VAR_SYMBOL) {
+ /* Convert raw ^C to corresponding special variable reference */
+ o_addchr(&ctx.word, SPECIAL_VAR_SYMBOL);
+ o_addchr(&ctx.word, SPECIAL_VAR_QUOTED_SVS);
+ }
+ o_addqchr(&ctx.word, ch);
+ ch = i_getch(input);
+ }
+ continue; /* get next char */
+ }
+
+ next = '\0';
+ if (ch != '\n')
+ next = i_peek_and_eat_bkslash_nl(input);
+
+ is_special = "{}<>&|();#" /* special outside of "str" */
+ "$\"" IF_HUSH_TICK("`") /* always special */
+ SPECIAL_VAR_SYMBOL_STR;
+#if defined(CMD_TEST2_SINGLEWORD_NOGLOB)
+ if (ctx.command->cmd_type == CMD_TEST2_SINGLEWORD_NOGLOB) {
+ /* In [[ ]], {}<>&|() are not special */
+ is_special += 8;
+ } else
+#endif
+ /* Are { and } special here? */
+ if (ctx.command->argv /* word [word]{... - non-special */
+ || ctx.word.length /* word{... - non-special */
+ || ctx.word.has_quoted_part /* ""{... - non-special */
+ || (next != ';' /* }; - special */
+ && next != ')' /* }) - special */
+ && next != '(' /* {( - special */
+ && next != '&' /* }& and }&& ... - special */
+ && next != '|' /* }|| ... - special */
+ && !strchr(defifs, next) /* {word - non-special */
+ )
+ ) {
+ /* They are not special, skip "{}" */
+ is_special += 2;
+ }
+ is_special = strchr(is_special, ch);
+ is_blank = strchr(defifs, ch);
+
+ if (!is_special && !is_blank) { /* ordinary char */
+ ordinary_char:
+ o_addQchr(&ctx.word, ch);
+ if ((ctx.is_assignment == MAYBE_ASSIGNMENT
+ || ctx.is_assignment == WORD_IS_KEYWORD)
+ && ch == '='
+ && endofname(ctx.word.data)[0] == '='
+ ) {
+ ctx.is_assignment = DEFINITELY_ASSIGNMENT;
+ debug_printf_parse("ctx.is_assignment='%s'\n", assignment_flag[ctx.is_assignment]);
+ }
+ continue;
+ }
+
+ if (is_blank) {
+#if ENABLE_HUSH_LINENO_VAR
+/* Case:
+ * "while ...; do<whitespace><newline>
+ * cmd ..."
+ * would think that "cmd" starts in <whitespace> -
+ * i.e., at the previous line.
+ * We need to skip all whitespace before newlines.
+ */
+ while (ch != '\n') {
+ next = i_peek(input);
+ if (next != ' ' && next != '\t' && next != '\n')
+ break; /* next char is not ws */
+ ch = i_getch(input);
+ }
+ /* ch == last eaten whitespace char */
+#endif
+ if (done_word(&ctx)) {
+ goto parse_error_exitcode1;
+ }
+ if (ch == '\n') {
+ /* Is this a case when newline is simply ignored?
+ * Some examples:
+ * "cmd | <newline> cmd ..."
+ * "case ... in <newline> word) ..."
+ */
+ if (IS_NULL_CMD(ctx.command)
+ && ctx.word.length == 0
+ && !ctx.word.has_quoted_part
+ && heredoc_cnt == 0
+ ) {
+ /* This newline can be ignored. But...
+ * Without check #1, interactive shell
+ * ignores even bare <newline>,
+ * and shows the continuation prompt:
+ * ps1_prompt$ <enter>
+ * ps2> _ <=== wrong, should be ps1
+ * Without check #2, "cmd & <newline>"
+ * is similarly mistreated.
+ * (BTW, this makes "cmd & cmd"
+ * and "cmd && cmd" non-orthogonal.
+ * Really, ask yourself, why
+ * "cmd && <newline>" doesn't start
+ * cmd but waits for more input?
+ * The only reason is that it might be
+ * a "cmd1 && <nl> cmd2 &" construct,
+ * cmd1 may need to run in BG).
+ */
+ struct pipe *pi = ctx.list_head;
+ if (pi->num_cmds != 0 /* check #1 */
+ && pi->followup != PIPE_BG /* check #2 */
+ ) {
+ continue;
+ }
+ }
+ /* Treat newline as a command separator. */
+ done_pipe(&ctx, PIPE_SEQ);
+ debug_printf_heredoc("heredoc_cnt:%d\n", heredoc_cnt);
+ if (heredoc_cnt) {
+ heredoc_cnt = fetch_heredocs(&ctx.as_string, ctx.list_head, heredoc_cnt, input);
+ if (heredoc_cnt != 0)
+ goto parse_error_exitcode1;
+ }
+ ctx.is_assignment = MAYBE_ASSIGNMENT;
+ debug_printf_parse("ctx.is_assignment='%s'\n", assignment_flag[ctx.is_assignment]);
+ ch = ';';
+ /* note: if (is_blank) continue;
+ * will still trigger for us */
+ }
+ }
+
+ /* "cmd}" or "cmd }..." without semicolon or &:
+ * } is an ordinary char in this case, even inside { cmd; }
+ * Pathological example: { ""}; } should exec "}" cmd
+ */
+ if (ch == '}') {
+ if (ctx.word.length != 0 /* word} */
+ || ctx.word.has_quoted_part /* ""} */
+ ) {
+ goto ordinary_char;
+ }
+ if (!IS_NULL_CMD(ctx.command)) { /* cmd } */
+ /* Generally, there should be semicolon: "cmd; }"
+ * However, bash allows to omit it if "cmd" is
+ * a group. Examples:
+ * { { echo 1; } }
+ * {(echo 1)}
+ * { echo 0 >&2 | { echo 1; } }
+ * { while false; do :; done }
+ * { case a in b) ;; esac }
+ */
+ if (ctx.command->group)
+ goto term_group;
+ goto ordinary_char;
+ }
+ if (!IS_NULL_PIPE(ctx.pipe)) /* cmd | } */
+ /* Can't be an end of {cmd}, skip the check */
+ goto skip_end_trigger;
+ /* else: } does terminate a group */
+ }
+ term_group:
+ if (end_trigger && end_trigger == ch
+ && (ch != ';' || heredoc_cnt == 0)
+#if ENABLE_HUSH_CASE
+ && (ch != ')'
+ || ctx.ctx_res_w != RES_MATCH
+ || (!ctx.word.has_quoted_part && strcmp(ctx.word.data, "esac") == 0)
+ )
+#endif
+ ) {
+ if (done_word(&ctx)) {
+ goto parse_error_exitcode1;
+ }
+ done_pipe(&ctx, PIPE_SEQ);
+ ctx.is_assignment = MAYBE_ASSIGNMENT;
+ debug_printf_parse("ctx.is_assignment='%s'\n", assignment_flag[ctx.is_assignment]);
+ /* Do we sit outside of any if's, loops or case's? */
+ if (!HAS_KEYWORDS
+ IF_HAS_KEYWORDS(|| (ctx.ctx_res_w == RES_NONE && ctx.old_flag == 0))
+ ) {
+ o_free_and_set_NULL(&ctx.word);
+#if !BB_MMU
+ debug_printf_parse("as_string2 '%s'\n", ctx.as_string.data);
+ if (pstring)
+ *pstring = ctx.as_string.data;
+ else
+ o_free(&ctx.as_string);
+#endif
+ if (ch != ';' && IS_NULL_PIPE(ctx.list_head)) {
+ /* Example: bare "{ }", "()" */
+ G.last_exitcode = 2; /* bash compat */
+ syntax_error_unexpected_ch(ch);
+ goto parse_error;
+ }
+ if (heredoc_cnt_ptr)
+ *heredoc_cnt_ptr = heredoc_cnt;
+ debug_printf_heredoc("parse_stream return heredoc_cnt:%d\n", heredoc_cnt);
+ debug_printf_parse("parse_stream return %p: "
+ "end_trigger char found\n",
+ ctx.list_head);
+ debug_leave();
+ return ctx.list_head;
+ }
+ }
+
+ if (is_blank)
+ continue;
+
+ /* Catch <, > before deciding whether this word is
+ * an assignment. a=1 2>z b=2: b=2 is still assignment */
+ switch (ch) {
+ case '>':
+ redir_fd = redirect_opt_num(&ctx.word);
+ if (done_word(&ctx)) {
+ goto parse_error_exitcode1;
+ }
+ redir_style = REDIRECT_OVERWRITE;
+ if (next == '>') {
+ redir_style = REDIRECT_APPEND;
+ ch = i_getch(input);
+ nommu_addchr(&ctx.as_string, ch);
+ }
+#if 0
+ else if (next == '(') {
+ syntax_error(">(process) not supported");
+ goto parse_error_exitcode1;
+ }
+#endif
+ if (parse_redirect(&ctx, redir_fd, redir_style, input))
+ goto parse_error_exitcode1;
+ continue; /* get next char */
+ case '<':
+ redir_fd = redirect_opt_num(&ctx.word);
+ if (done_word(&ctx)) {
+ goto parse_error_exitcode1;
+ }
+ redir_style = REDIRECT_INPUT;
+ if (next == '<') {
+ redir_style = REDIRECT_HEREDOC;
+ heredoc_cnt++;
+ debug_printf_heredoc("++heredoc_cnt=%d\n", heredoc_cnt);
+ ch = i_getch(input);
+ nommu_addchr(&ctx.as_string, ch);
+ } else if (next == '>') {
+ redir_style = REDIRECT_IO;
+ ch = i_getch(input);
+ nommu_addchr(&ctx.as_string, ch);
+ }
+#if 0
+ else if (next == '(') {
+ syntax_error("<(process) not supported");
+ goto parse_error_exitcode1;
+ }
+#endif
+ if (parse_redirect(&ctx, redir_fd, redir_style, input))
+ goto parse_error_exitcode1;
+ continue; /* get next char */
+ case '#':
+ if (ctx.word.length == 0 && !ctx.word.has_quoted_part) {
+ /* skip "#comment" */
+ /* note: we do not add it to &ctx.as_string */
+/* TODO: in bash:
+ * comment inside $() goes to the next \n, even inside quoted string (!):
+ * cmd "$(cmd2 #comment)" - syntax error
+ * cmd "`cmd2 #comment`" - ok
+ * We accept both (comment ends where command subst ends, in both cases).
+ */
+ while (1) {
+ ch = i_peek(input);
+ if (ch == '\n') {
+ nommu_addchr(&ctx.as_string, '\n');
+ break;
+ }
+ ch = i_getch(input);
+ if (ch == EOF)
+ break;
+ }
+ continue; /* get next char */
+ }
+ break;
+ }
+ skip_end_trigger:
+
+ if (ctx.is_assignment == MAYBE_ASSIGNMENT
+ /* check that we are not in word in "a=1 2>word b=1": */
+ && !ctx.pending_redirect
+ ) {
+ /* ch is a special char and thus this word
+ * cannot be an assignment */
+ ctx.is_assignment = NOT_ASSIGNMENT;
+ debug_printf_parse("ctx.is_assignment='%s'\n", assignment_flag[ctx.is_assignment]);
+ }
+
+ /* Note: nommu_addchr(&ctx.as_string, ch) is already done */
+
+ switch (ch) {
+ case_SPECIAL_VAR_SYMBOL:
+ case SPECIAL_VAR_SYMBOL:
+ /* Convert raw ^C to corresponding special variable reference */
+ o_addchr(&ctx.word, SPECIAL_VAR_SYMBOL);
+ o_addchr(&ctx.word, SPECIAL_VAR_QUOTED_SVS);
+ /* fall through */
+ case '#':
+ /* non-comment #: "echo a#b" etc */
+ o_addchr(&ctx.word, ch);
+ continue; /* get next char */
+ case '$':
+ if (parse_dollar_squote(&ctx.as_string, &ctx.word, input))
+ continue; /* get next char */
+ if (!parse_dollar(&ctx.as_string, &ctx.word, input, /*quote_mask:*/ 0)) {
+ debug_printf_parse("parse_stream parse error: "
+ "parse_dollar returned 0 (error)\n");
+ goto parse_error_exitcode1;
+ }
+ continue; /* get next char */
+ case '"':
+ ctx.word.has_quoted_part = 1;
+ if (next == '"' && !ctx.pending_redirect) {
+ i_getch(input); /* eat second " */
+ insert_empty_quoted_str_marker:
+ nommu_addchr(&ctx.as_string, next);
+ o_addchr(&ctx.word, SPECIAL_VAR_SYMBOL);
+ o_addchr(&ctx.word, SPECIAL_VAR_SYMBOL);
+ continue; /* get next char */
+ }
+ if (ctx.is_assignment == NOT_ASSIGNMENT)
+ ctx.word.o_expflags |= EXP_FLAG_ESC_GLOB_CHARS;
+ if (!encode_string(&ctx.as_string, &ctx.word, input, '"'))
+ goto parse_error_exitcode1;
+ ctx.word.o_expflags &= ~EXP_FLAG_ESC_GLOB_CHARS;
+ continue; /* get next char */
+#if ENABLE_HUSH_TICK
+ case '`': {
+ USE_FOR_NOMMU(unsigned pos;)
+
+ o_addchr(&ctx.word, SPECIAL_VAR_SYMBOL);
+ o_addchr(&ctx.word, '`');
+ USE_FOR_NOMMU(pos = ctx.word.length;)
+ if (!add_till_backquote(&ctx.word, input, /*in_dquote:*/ 0))
+ goto parse_error_exitcode1;
+# if !BB_MMU
+ o_addstr(&ctx.as_string, ctx.word.data + pos);
+ o_addchr(&ctx.as_string, '`');
+# endif
+ o_addchr(&ctx.word, SPECIAL_VAR_SYMBOL);
+ //debug_printf_subst("SUBST RES3 '%s'\n", ctx.word.data + pos);
+ continue; /* get next char */
+ }
+#endif
+ case ';':
+#if ENABLE_HUSH_CASE
+ case_semi:
+#endif
+ if (done_word(&ctx)) {
+ goto parse_error_exitcode1;
+ }
+ done_pipe(&ctx, PIPE_SEQ);
+#if ENABLE_HUSH_CASE
+ /* Eat multiple semicolons, detect
+ * whether it means something special */
+ while (1) {
+ ch = i_peek_and_eat_bkslash_nl(input);
+ if (ch != ';')
+ break;
+ ch = i_getch(input);
+ nommu_addchr(&ctx.as_string, ch);
+ if (ctx.ctx_res_w == RES_CASE_BODY) {
+ ctx.ctx_dsemicolon = 1;
+ ctx.ctx_res_w = RES_MATCH;
+ break;
+ }
+ }
+#endif
+ new_cmd:
+ /* We just finished a cmd. New one may start
+ * with an assignment */
+ ctx.is_assignment = MAYBE_ASSIGNMENT;
+ debug_printf_parse("ctx.is_assignment='%s'\n", assignment_flag[ctx.is_assignment]);
+ continue; /* get next char */
+ case '&':
+ if (done_word(&ctx)) {
+ goto parse_error_exitcode1;
+ }
+ if (next == '&') {
+ ch = i_getch(input);
+ nommu_addchr(&ctx.as_string, ch);
+ done_pipe(&ctx, PIPE_AND);
+ } else {
+ done_pipe(&ctx, PIPE_BG);
+ }
+ goto new_cmd;
+ case '|':
+ if (done_word(&ctx)) {
+ goto parse_error_exitcode1;
+ }
+#if ENABLE_HUSH_CASE
+ if (ctx.ctx_res_w == RES_MATCH)
+ break; /* we are in case's "word | word)" */
+#endif
+ if (next == '|') { /* || */
+ ch = i_getch(input);
+ nommu_addchr(&ctx.as_string, ch);
+ done_pipe(&ctx, PIPE_OR);
+ } else {
+ /* we could pick up a file descriptor choice here
+ * with redirect_opt_num(), but bash doesn't do it.
+ * "echo foo 2| cat" yields "foo 2". */
+ done_command(&ctx);
+ }
+ goto new_cmd;
+ case '(':
+#if ENABLE_HUSH_CASE
+ /* "case... in [(]word)..." - skip '(' */
+ if (ctx.ctx_res_w == RES_MATCH
+ && ctx.command->argv == NULL /* not (word|(... */
+ && ctx.word.length == 0 /* not word(... */
+ && ctx.word.has_quoted_part == 0 /* not ""(... */
+ ) {
+ continue; /* get next char */
+ }
+#endif
+ /* fall through */
+ case '{': {
+ int n = parse_group(&ctx, input, ch);
+ if (n < 0) {
+ goto parse_error_exitcode1;
+ }
+ debug_printf_heredoc("parse_group done, needs heredocs:%d\n", n);
+ heredoc_cnt += n;
+ goto new_cmd;
+ }
+ case ')':
+#if ENABLE_HUSH_CASE
+ if (ctx.ctx_res_w == RES_MATCH)
+ goto case_semi;
+#endif
+ case '}':
+ /* proper use of this character is caught by end_trigger:
+ * if we see {, we call parse_group(..., end_trigger='}')
+ * and it will match } earlier (not here). */
+ G.last_exitcode = 2;
+ syntax_error_unexpected_ch(ch);
+ goto parse_error;
+ default:
+ if (HUSH_DEBUG)
+ bb_error_msg_and_die("BUG: unexpected %c", ch);
+ }
+ } /* while (1) */
+
+ parse_error_exitcode1:
+ G.last_exitcode = 1;
+ parse_error:
+ {
+ struct parse_context *pctx;
+ IF_HAS_KEYWORDS(struct parse_context *p2;)
+
+ /* Clean up allocated tree.
+ * Sample for finding leaks on syntax error recovery path.
+ * Run it from interactive shell, watch pmap `pidof hush`.
+ * while if false; then false; fi; do break; fi
+ * Samples to catch leaks at execution:
+ * while if (true | { true;}); then echo ok; fi; do break; done
+ * while if (true | { true;}); then echo ok; fi; do (if echo ok; break; then :; fi) | cat; break; done
+ */
+ pctx = &ctx;
+ do {
+ /* Update pipe/command counts,
+ * otherwise freeing may miss some */
+ done_pipe(pctx, PIPE_SEQ);
+ debug_printf_clean("freeing list %p from ctx %p\n",
+ pctx->list_head, pctx);
+ debug_print_tree(pctx->list_head, 0);
+ free_pipe_list(pctx->list_head);
+ debug_printf_clean("freed list %p\n", pctx->list_head);
+#if !BB_MMU
+ o_free(&pctx->as_string);
+#endif
+ IF_HAS_KEYWORDS(p2 = pctx->stack;)
+ if (pctx != &ctx) {
+ free(pctx);
+ }
+ IF_HAS_KEYWORDS(pctx = p2;)
+ } while (HAS_KEYWORDS && pctx);
+
+ o_free(&ctx.word);
+#if !BB_MMU
+ if (pstring)
+ *pstring = NULL;
+#endif
+ debug_leave();
+ return ERR_PTR;
+ }
+}
+
+
+/*** Execution routines ***/
+
+/* Expansion can recurse, need forward decls: */
+#if !BASH_PATTERN_SUBST && !ENABLE_HUSH_CASE
+#define expand_string_to_string(str, EXP_flags, do_unbackslash) \
+ expand_string_to_string(str)
+#endif
+static char *expand_string_to_string(const char *str, int EXP_flags, int do_unbackslash);
+#if ENABLE_HUSH_TICK
+static int process_command_subs(o_string *dest, const char *s);
+#endif
+static int expand_vars_to_list(o_string *output, int n, char *arg);
+
+/* expand_strvec_to_strvec() takes a list of strings, expands
+ * all variable references within and returns a pointer to
+ * a list of expanded strings, possibly with larger number
+ * of strings. (Think VAR="a b"; echo $VAR).
+ * This new list is allocated as a single malloc block.
+ * NULL-terminated list of char* pointers is at the beginning of it,
+ * followed by strings themselves.
+ * Caller can deallocate entire list by single free(list). */
+
+/* A horde of its helpers come first: */
+
+static void o_addblock_duplicate_backslash(o_string *o, const char *str, int len)
+{
+ while (--len >= 0) {
+ char c = *str++;
+
+#if ENABLE_HUSH_BRACE_EXPANSION
+ if (c == '{' || c == '}') {
+ /* { -> \{, } -> \} */
+ o_addchr(o, '\\');
+ /* And now we want to add { or } and continue:
+ * o_addchr(o, c);
+ * continue;
+ * luckily, just falling through achieves this.
+ */
+ }
+#endif
+ o_addchr(o, c);
+ if (c == '\\') {
+ /* \z -> \\\z; \<eol> -> \\<eol> */
+ o_addchr(o, '\\');
+ if (len) {
+ len--;
+ o_addchr(o, '\\');
+ o_addchr(o, *str++);
+ }
+ }
+ }
+}
+
+/* Store given string, finalizing the word and starting new one whenever
+ * we encounter IFS char(s). This is used for expanding variable values.
+ * End-of-string does NOT finalize word: think about 'echo -$VAR-'.
+ * Return in output->ended_in_ifs:
+ * 1 - ended with IFS char, else 0 (this includes case of empty str).
+ */
+static int expand_on_ifs(o_string *output, int n, const char *str)
+{
+ int last_is_ifs = 0;
+
+ while (1) {
+ int word_len;
+
+ if (!*str) /* EOL - do not finalize word */
+ break;
+ word_len = strcspn(str, G.ifs);
+ if (word_len) {
+ /* We have WORD_LEN leading non-IFS chars */
+ if (!(output->o_expflags & EXP_FLAG_GLOB)) {
+ o_addblock(output, str, word_len);
+ } else {
+ /* Protect backslashes against globbing up :)
+ * Example: "v='\*'; echo b$v" prints "b\*"
+ * (and does not try to glob on "*")
+ */
+ o_addblock_duplicate_backslash(output, str, word_len);
+ /*/ Why can't we do it easier? */
+ /*o_addblock(output, str, word_len); - WRONG: "v='\*'; echo Z$v" prints "Z*" instead of "Z\*" */
+ /*o_addqblock(output, str, word_len); - WRONG: "v='*'; echo Z$v" prints "Z*" instead of Z* files */
+ }
+ last_is_ifs = 0;
+ str += word_len;
+ if (!*str) /* EOL - do not finalize word */
+ break;
+ }
+
+ /* We know str here points to at least one IFS char */
+ last_is_ifs = 1;
+ str += strspn(str, G.ifs_whitespace); /* skip IFS whitespace chars */
+ if (!*str) /* EOL - do not finalize word */
+ break;
+
+ if (G.ifs_whitespace != G.ifs /* usually false ($IFS is usually all whitespace), */
+ && strchr(G.ifs, *str) /* the second check would fail */
+ ) {
+ /* This is a non-whitespace $IFS char */
+ /* Skip it and IFS whitespace chars, start new word */
+ str++;
+ str += strspn(str, G.ifs_whitespace);
+ goto new_word;
+ }
+
+ /* Start new word... but not always! */
+ /* Case "v=' a'; echo ''$v": we do need to finalize empty word: */
+ if (output->has_quoted_part
+ /*
+ * Case "v=' a'; echo $v":
+ * here nothing precedes the space in $v expansion,
+ * therefore we should not finish the word
+ * (IOW: if there *is* word to finalize, only then do it):
+ * It's okay if this accesses the byte before first argv[]:
+ * past call to o_save_ptr() cleared it to zero byte
+ * (grep for -prev-ifs-check-).
+ */
+ || output->data[output->length - 1]
+ ) {
+ new_word:
+ o_addchr(output, '\0');
+ debug_print_list("expand_on_ifs", output, n);
+ n = o_save_ptr(output, n);
+ }
+ }
+
+ output->ended_in_ifs = last_is_ifs;
+ debug_print_list("expand_on_ifs[1]", output, n);
+ return n;
+}
+
+/* Helper to expand $((...)) and heredoc body. These act as if
+ * they are in double quotes, with the exception that they are not :).
+ * Just the rules are similar: "expand only $var and `cmd`"
+ *
+ * Returns malloced string.
+ * As an optimization, we return NULL if expansion is not needed.
+ */
+static char *encode_then_expand_string(const char *str)
+{
+ char *exp_str;
+ struct in_str input;
+ o_string dest = NULL_O_STRING;
+ const char *cp;
+
+ cp = str;
+ for (;;) {
+ if (!*cp) return NULL; /* string has no special chars */
+ if (*cp == '$') break;
+ if (*cp == '\\') break;
+#if ENABLE_HUSH_TICK
+ if (*cp == '`') break;
+#endif
+ cp++;
+ }
+
+ /* We need to expand. Example:
+ * echo $(($a + `echo 1`)) $((1 + $((2)) ))
+ */
+ setup_string_in_str(&input, str);
+ encode_string(NULL, &dest, &input, EOF);
+//TODO: error check (encode_string returns 0 on error)?
+ //bb_error_msg("'%s' -> '%s'", str, dest.data);
+ exp_str = expand_string_to_string(dest.data,
+ EXP_FLAG_ESC_GLOB_CHARS,
+ /*unbackslash:*/ 1
+ );
+ //bb_error_msg("'%s' -> '%s'", dest.data, exp_str);
+ o_free(&dest);
+ return exp_str;
+}
+
+static const char *first_special_char_in_vararg(const char *cp)
+{
+ for (;;) {
+ if (!*cp) return NULL; /* string has no special chars */
+ if (*cp == '$') return cp;
+ if (*cp == '\\') return cp;
+ if (*cp == '\'') return cp;
+ if (*cp == '"') return cp;
+#if ENABLE_HUSH_TICK
+ if (*cp == '`') return cp;
+#endif
+ /* dquoted "${x:+ARG}" should not glob, therefore
+ * '*' et al require some non-literal processing: */
+ if (*cp == '*') return cp;
+ if (*cp == '?') return cp;
+ if (*cp == '[') return cp;
+ cp++;
+ }
+}
+
+/* Expanding ARG in ${var#ARG}, ${var%ARG}, or ${var/ARG/ARG}.
+ * These can contain single- and double-quoted strings,
+ * and treated as if the ARG string is initially unquoted. IOW:
+ * ${var#ARG} and "${var#ARG}" treat ARG the same (ARG can even be
+ * a dquoted string: "${var#"zz"}"), the difference only comes later
+ * (word splitting and globbing of the ${var...} result).
+ */
+#if !BASH_PATTERN_SUBST
+#define encode_then_expand_vararg(str, handle_squotes, do_unbackslash) \
+ encode_then_expand_vararg(str, handle_squotes)
+#endif
+static char *encode_then_expand_vararg(const char *str, int handle_squotes, int do_unbackslash)
+{
+#if !BASH_PATTERN_SUBST && ENABLE_HUSH_CASE
+ const int do_unbackslash = 0;
+#endif
+ char *exp_str;
+ struct in_str input;
+ o_string dest = NULL_O_STRING;
+
+ if (!first_special_char_in_vararg(str)) {
+ /* string has no special chars */
+ return NULL;
+ }
+
+ setup_string_in_str(&input, str);
+ dest.data = xzalloc(1); /* start as "", not as NULL */
+ exp_str = NULL;
+
+ for (;;) {
+ int ch;
+
+ ch = i_getch(&input);
+ debug_printf_parse("%s: ch=%c (%d) escape=%d\n",
+ __func__, ch, ch, !!dest.o_expflags);
+
+ if (!dest.o_expflags) {
+ if (ch == EOF)
+ break;
+ if (handle_squotes && ch == '\'') {
+ if (!add_till_single_quote_dquoted(&dest, &input))
+ goto ret; /* error */
+ continue;
+ }
+ }
+ if (ch == EOF) {
+ syntax_error_unterm_ch('"');
+ goto ret; /* error */
+ }
+ if (ch == '"') {
+ dest.o_expflags ^= EXP_FLAG_ESC_GLOB_CHARS;
+ continue;
+ }
+ if (ch == '\\') {
+ ch = i_getch(&input);
+ if (ch == EOF) {
+//example? error message? syntax_error_unterm_ch('"');
+ debug_printf_parse("%s: error: \\<eof>\n", __func__);
+ goto ret;
+ }
+ o_addqchr(&dest, ch);
+ continue;
+ }
+ if (ch == '$') {
+ if (parse_dollar_squote(NULL, &dest, &input))
+ continue;
+ if (!parse_dollar(NULL, &dest, &input, /*quote_mask:*/ 0x80)) {
+ debug_printf_parse("%s: error: parse_dollar returned 0 (error)\n", __func__);
+ goto ret;
+ }
+ continue;
+ }
+#if ENABLE_HUSH_TICK
+ if (ch == '`') {
+ //unsigned pos = dest->length;
+ o_addchr(&dest, SPECIAL_VAR_SYMBOL);
+ o_addchr(&dest, 0x80 | '`');
+ if (!add_till_backquote(&dest, &input,
+ /*in_dquote:*/ dest.o_expflags /* nonzero if EXP_FLAG_ESC_GLOB_CHARS set */
+ )
+ ) {
+ goto ret; /* error */
+ }
+ o_addchr(&dest, SPECIAL_VAR_SYMBOL);
+ //debug_printf_subst("SUBST RES3 '%s'\n", dest->data + pos);
+ continue;
+ }
+#endif
+ o_addQchr(&dest, ch);
+ } /* for (;;) */
+
+ debug_printf_parse("encode: '%s' -> '%s'\n", str, dest.data);
+ exp_str = expand_string_to_string(dest.data,
+ do_unbackslash ? EXP_FLAG_ESC_GLOB_CHARS : 0,
+ do_unbackslash
+ );
+ ret:
+ debug_printf_parse("expand: '%s' -> '%s'\n", dest.data, exp_str);
+ o_free(&dest);
+ return exp_str;
+}
+
+/* Expanding ARG in ${var+ARG}, ${var-ARG}
+ */
+static int encode_then_append_var_plusminus(o_string *output, int n,
+ char *str, int dquoted)
+{
+ struct in_str input;
+ o_string dest = NULL_O_STRING;
+
+ if (!first_special_char_in_vararg(str)
+ && '\0' == str[strcspn(str, G.ifs)]
+ ) {
+ /* string has no special chars
+ * && string has no $IFS chars
+ */
+ if (dquoted) {
+ /* Prints 1 (quoted expansion is a "" word, not nothing):
+ * set -- "${notexist-}"; echo $#
+ */
+ output->has_quoted_part = 1;
+ }
+ return expand_vars_to_list(output, n, str);
+ }
+
+ setup_string_in_str(&input, str);
+
+ for (;;) {
+ int ch;
+
+ ch = i_getch(&input);
+ debug_printf_parse("%s: ch=%c (%d) escape=%x\n",
+ __func__, ch, ch, dest.o_expflags);
+
+ if (!dest.o_expflags) {
+ if (ch == EOF)
+ break;
+ if (!dquoted && strchr(G.ifs, ch)) {
+ /* PREFIX${x:d${e}f ...} and we met space: expand "d${e}f" and start new word.
+ * do not assume we are at the start of the word (PREFIX above).
+ */
+ if (dest.data) {
+ n = expand_vars_to_list(output, n, dest.data);
+ o_free_and_set_NULL(&dest);
+ o_addchr(output, '\0');
+ n = o_save_ptr(output, n); /* create next word */
+ } else
+ if (output->length != o_get_last_ptr(output, n)
+ || output->has_quoted_part
+ ) {
+ /* For these cases:
+ * f() { for i; do echo "|$i|"; done; }; x=x
+ * f a${x:+ }b # 1st condition
+ * |a|
+ * |b|
+ * f ""${x:+ }b # 2nd condition
+ * ||
+ * |b|
+ */
+ o_addchr(output, '\0');
+ n = o_save_ptr(output, n); /* create next word */
+ }
+ continue;
+ }
+ if (!dquoted && ch == '\'') {
+ if (!add_till_single_quote_dquoted(&dest, &input))
+ goto ret; /* error */
+ o_addchr(&dest, SPECIAL_VAR_SYMBOL);
+ o_addchr(&dest, SPECIAL_VAR_SYMBOL);
+ continue;
+ }
+ }
+ if (ch == EOF) {
+ syntax_error_unterm_ch('"');
+ goto ret; /* error */
+ }
+ if (ch == '"') {
+ dest.o_expflags ^= EXP_FLAG_ESC_GLOB_CHARS;
+ if (dest.o_expflags) {
+ o_addchr(&dest, SPECIAL_VAR_SYMBOL);
+ o_addchr(&dest, SPECIAL_VAR_SYMBOL);
+ }
+ continue;
+ }
+ if (ch == '\\') {
+ ch = i_getch(&input);
+ if (ch == EOF) {
+//example? error message? syntax_error_unterm_ch('"');
+ debug_printf_parse("%s: error: \\<eof>\n", __func__);
+ goto ret;
+ }
+ o_addqchr(&dest, ch);
+ continue;
+ }
+ if (ch == '$') {
+ if (!parse_dollar(NULL, &dest, &input, /*quote_mask:*/ (dest.o_expflags || dquoted) ? 0x80 : 0)) {
+ debug_printf_parse("%s: error: parse_dollar returned 0 (error)\n", __func__);
+ goto ret;
+ }
+ continue;
+ }
+#if ENABLE_HUSH_TICK
+ if (ch == '`') {
+ //unsigned pos = dest->length;
+ o_addchr(&dest, SPECIAL_VAR_SYMBOL);
+ o_addchr(&dest, (dest.o_expflags || dquoted) ? 0x80 | '`' : '`');
+ if (!add_till_backquote(&dest, &input,
+ /*in_dquote:*/ dest.o_expflags /* nonzero if EXP_FLAG_ESC_GLOB_CHARS set */
+ )
+ ) {
+ goto ret; /* error */
+ }
+ o_addchr(&dest, SPECIAL_VAR_SYMBOL);
+ //debug_printf_subst("SUBST RES3 '%s'\n", dest->data + pos);
+ continue;
+ }
+#endif
+ if (dquoted) {
+ /* Always glob-protect if in dquotes:
+ * x=x; echo "${x:+/bin/c*}" - prints: /bin/c*
+ * x=x; echo "${x:+"/bin/c*"}" - prints: /bin/c*
+ */
+ o_addqchr(&dest, ch);
+ } else {
+ /* Glob-protect only if char is quoted:
+ * x=x; echo ${x:+/bin/c*} - prints many filenames
+ * x=x; echo ${x:+"/bin/c*"} - prints: /bin/c*
+ */
+ o_addQchr(&dest, ch);
+ }
+ } /* for (;;) */
+
+ if (dest.data) {
+ n = expand_vars_to_list(output, n, dest.data);
+ }
+ ret:
+ o_free(&dest);
+ return n;
+}
+
+#if ENABLE_FEATURE_SH_MATH
+static arith_t expand_and_evaluate_arith(const char *arg, const char **errmsg_p)
+{
+ arith_state_t math_state;
+ arith_t res;
+ char *exp_str;
+
+ math_state.lookupvar = get_local_var_value;
+ math_state.setvar = set_local_var_from_halves;
+ //math_state.endofname = endofname;
+ exp_str = encode_then_expand_string(arg);
+ res = arith(&math_state, exp_str ? exp_str : arg);
+ free(exp_str);
+ if (errmsg_p)
+ *errmsg_p = math_state.errmsg;
+ if (math_state.errmsg)
+ msg_and_die_if_script(math_state.errmsg);
+ return res;
+}
+#endif
+
+#if BASH_PATTERN_SUBST
+/* ${var/[/]pattern[/repl]} helpers */
+static char *strstr_pattern(char *val, const char *pattern, int *size)
+{
+ int sz = strcspn(pattern, "*?[\\");
+ if (pattern[sz] == '\0') {
+ /* Optimization for trivial patterns.
+ * Testcase for very slow replace (performs about 22k replaces):
+ * x=::::::::::::::::::::::
+ * x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;echo ${#x}
+ * echo "${x//:/|}"
+ */
+ *size = sz;
+ return strstr(val, pattern);
+ }
+
+ while (1) {
+ char *end = scan_and_match(val, pattern, SCAN_MOVE_FROM_RIGHT + SCAN_MATCH_LEFT_HALF);
+ debug_printf_varexp("val:'%s' pattern:'%s' end:'%s'\n", val, pattern, end);
+ if (end) {
+ *size = end - val;
+ return val;
+ }
+ if (*val == '\0')
+ return NULL;
+ /* Optimization: if "*pat" did not match the start of "string",
+ * we know that "tring", "ring" etc will not match too:
+ */
+ if (pattern[0] == '*')
+ return NULL;
+ val++;
+ }
+}
+static char *replace_pattern(char *val, const char *pattern, const char *repl, char exp_op)
+{
+ char *result = NULL;
+ unsigned res_len = 0;
+ unsigned repl_len = strlen(repl);
+
+ /* Null pattern never matches, including if "var" is empty */
+ if (!pattern[0])
+ return result; /* NULL, no replaces happened */
+
+ while (1) {
+ int size;
+ char *s = strstr_pattern(val, pattern, &size);
+ if (!s)
+ break;
+
+ result = xrealloc(result, res_len + (s - val) + repl_len + 1);
+ strcpy(mempcpy(result + res_len, val, s - val), repl);
+ res_len += (s - val) + repl_len;
+ debug_printf_varexp("val:'%s' s:'%s' result:'%s'\n", val, s, result);
+
+ val = s + size;
+ if (exp_op == '/')
+ break;
+ }
+ if (*val && result) {
+ result = xrealloc(result, res_len + strlen(val) + 1);
+ strcpy(result + res_len, val);
+ debug_printf_varexp("val:'%s' result:'%s'\n", val, result);
+ }
+ debug_printf_varexp("result:'%s'\n", result);
+ return result;
+}
+#endif /* BASH_PATTERN_SUBST */
+
+static int append_str_maybe_ifs_split(o_string *output, int n,
+ int first_ch, const char *val)
+{
+ if (!(first_ch & 0x80)) { /* unquoted $VAR */
+ debug_printf_expand("unquoted '%s', output->o_escape:%d\n", val,
+ !!(output->o_expflags & EXP_FLAG_ESC_GLOB_CHARS));
+ if (val && val[0])
+ n = expand_on_ifs(output, n, val);
+ } else { /* quoted "$VAR" */
+ output->has_quoted_part = 1;
+ debug_printf_expand("quoted '%s', output->o_escape:%d\n", val,
+ !!(output->o_expflags & EXP_FLAG_ESC_GLOB_CHARS));
+ if (val && val[0])
+ o_addQstr(output, val);
+ }
+ return n;
+}
+
+/* Handle <SPECIAL_VAR_SYMBOL>varname...<SPECIAL_VAR_SYMBOL> construct.
+ */
+static NOINLINE int expand_one_var(o_string *output, int n,
+ int first_ch, char *arg, char **pp)
+{
+ const char *val;
+ char *to_be_freed;
+ char *p;
+ char *var;
+ char exp_op;
+ char exp_save = exp_save; /* for compiler */
+ char *exp_saveptr; /* points to expansion operator */
+ char *exp_word = exp_word; /* for compiler */
+ char arg0;
+
+ val = NULL;
+ to_be_freed = NULL;
+ p = *pp;
+ *p = '\0'; /* replace trailing SPECIAL_VAR_SYMBOL */
+ var = arg;
+ exp_saveptr = arg[1] ? strchr(VAR_ENCODED_SUBST_OPS, arg[1]) : NULL;
+ arg0 = arg[0];
+ arg[0] = (arg0 & 0x7f);
+ exp_op = 0;
+
+ if (arg[0] == '#' && arg[1] /* ${#...} but not ${#} */
+ && (!exp_saveptr /* and ( not(${#<op_char>...}) */
+ || (arg[2] == '\0' && strchr(SPECIAL_VARS_STR, arg[1])) /* or ${#C} "len of $C" ) */
+ ) /* NB: skipping ^^^specvar check mishandles ${#::2} */
+ ) {
+ /* It must be length operator: ${#var} */
+ var++;
+ exp_op = 'L';
+ } else {
+ /* Maybe handle parameter expansion */
+ if (exp_saveptr /* if 2nd char is one of expansion operators */
+ && strchr(NUMERIC_SPECVARS_STR, arg[0]) /* 1st char is special variable */
+ ) {
+ /* ${?:0}, ${#[:]%0} etc */
+ exp_saveptr = var + 1;
+ } else {
+ /* ${?}, ${var}, ${var:0}, ${var[:]%0} etc */
+ exp_saveptr = var+1 + strcspn(var+1, VAR_ENCODED_SUBST_OPS);
+ }
+ exp_op = exp_save = *exp_saveptr;
+ if (exp_op) {
+ exp_word = exp_saveptr + 1;
+ if (exp_op == ':') {
+ exp_op = *exp_word++;
+//TODO: try ${var:} and ${var:bogus} in non-bash config
+ if (BASH_SUBSTR
+ && (!exp_op || !strchr(MINUS_PLUS_EQUAL_QUESTION, exp_op))
+ ) {
+ /* oops... it's ${var:N[:M]}, not ${var:?xxx} or some such */
+ exp_op = ':';
+ exp_word--;
+ }
+ }
+ *exp_saveptr = '\0';
+ } /* else: it's not an expansion op, but bare ${var} */
+ }
+
+ /* Look up the variable in question */
+ if (isdigit(var[0])) {
+ /* parse_dollar should have vetted var for us */
+ int nn = xatoi_positive(var);
+ if (nn < G.global_argc)
+ val = G.global_argv[nn];
+ /* else val remains NULL: $N with too big N */
+ } else {
+ switch (var[0]) {
+ case '$': /* pid */
+ val = utoa(G.root_pid);
+ break;
+ case '!': /* bg pid */
+ val = G.last_bg_pid ? utoa(G.last_bg_pid) : "";
+ break;
+ case '?': /* exitcode */
+ val = utoa(G.last_exitcode);
+ break;
+ case '#': /* argc */
+ val = utoa(G.global_argc ? G.global_argc-1 : 0);
+ break;
+ case '-': { /* active options */
+ /* Check set_mode() to see what option chars we support */
+ char *cp;
+ val = cp = G.optstring_buf;
+ if (G.o_opt[OPT_O_ERREXIT])
+ *cp++ = 'e';
+ if (G_interactive_fd)
+ *cp++ = 'i';
+ if (G_x_mode)
+ *cp++ = 'x';
+ /* If G.o_opt[OPT_O_NOEXEC] is true,
+ * commands read but are not executed,
+ * so $- can not execute too, 'n' is never seen in $-.
+ */
+ if (G.opt_c)
+ *cp++ = 'c';
+ if (G.opt_s)
+ *cp++ = 's';
+ *cp = '\0';
+ break;
+ }
+ default:
+ val = get_local_var_value(var);
+ }
+ }
+
+ /* Handle any expansions */
+ if (exp_op == 'L') {
+ reinit_unicode_for_hush();
+ debug_printf_expand("expand: length(%s)=", val);
+ val = utoa(val ? unicode_strlen(val) : 0);
+ debug_printf_expand("%s\n", val);
+ } else if (exp_op) {
+ if (exp_op == '%' || exp_op == '#') {
+ /* Standard-mandated substring removal ops:
+ * ${parameter%word} - remove smallest suffix pattern
+ * ${parameter%%word} - remove largest suffix pattern
+ * ${parameter#word} - remove smallest prefix pattern
+ * ${parameter##word} - remove largest prefix pattern
+ *
+ * Word is expanded to produce a glob pattern.
+ * Then var's value is matched to it and matching part removed.
+ */
+ /* bash compat: if x is "" and no shrinking of it is possible,
+ * inner ${...} is not evaluated. Example:
+ * unset b; : ${a%${b=B}}; echo $b
+ * assignment b=B only happens if $a is not "".
+ */
+ if (val && val[0]) {
+ char *t;
+ char *exp_exp_word;
+ char *loc;
+ unsigned scan_flags = pick_scan(exp_op, *exp_word);
+ if (exp_op == *exp_word) /* ## or %% */
+ exp_word++;
+ debug_printf_expand("expand: exp_word:'%s'\n", exp_word);
+ exp_exp_word = encode_then_expand_vararg(exp_word, /*handle_squotes:*/ 1, /*unbackslash:*/ 0);
+ if (exp_exp_word)
+ exp_word = exp_exp_word;
+ debug_printf_expand("expand: exp_word:'%s'\n", exp_word);
+ /*
+ * HACK ALERT. We depend here on the fact that
+ * G.global_argv and results of utoa and get_local_var_value
+ * are actually in writable memory:
+ * scan_and_match momentarily stores NULs there.
+ */
+ t = (char*)val;
+ loc = scan_and_match(t, exp_word, scan_flags);
+ debug_printf_expand("op:%c str:'%s' pat:'%s' res:'%s'\n", exp_op, t, exp_word, loc);
+ free(exp_exp_word);
+ if (loc) { /* match was found */
+ if (scan_flags & SCAN_MATCH_LEFT_HALF) /* #[#] */
+ val = loc; /* take right part */
+ else /* %[%] */
+ val = to_be_freed = xstrndup(val, loc - val); /* left */
+ }
+ }
+ }
+#if BASH_PATTERN_SUBST
+ else if (exp_op == '/' || exp_op == '\\') {
+ /* It's ${var/[/]pattern[/repl]} thing.
+ * Note that in encoded form it has TWO parts:
+ * var/pattern<SPECIAL_VAR_SYMBOL>repl<SPECIAL_VAR_SYMBOL>
+ * and if // is used, it is encoded as \:
+ * var\pattern<SPECIAL_VAR_SYMBOL>repl<SPECIAL_VAR_SYMBOL>
+ */
+ /* bash compat: if var is "", both pattern and repl
+ * are still evaluated, if it is unset, then not:
+ * unset b; a=; : ${a/z/${b=3}}; echo $b # b=3
+ * unset b; unset a; : ${a/z/${b=3}}; echo $b # b not set
+ */
+ if (val /*&& val[0]*/) {
+ /* pattern uses non-standard expansion.
+ * repl should be unbackslashed and globbed
+ * by the usual expansion rules:
+ * >az >bz
+ * v='a bz'; echo "${v/a*z/a*z}" #prints "a*z"
+ * v='a bz'; echo "${v/a*z/\z}" #prints "z"
+ * v='a bz'; echo ${v/a*z/a*z} #prints "az"
+ * v='a bz'; echo ${v/a*z/\z} #prints "z"
+ * (note that a*z _pattern_ is never globbed!)
+ */
+ char *pattern, *repl, *t;
+ pattern = encode_then_expand_vararg(exp_word, /*handle_squotes:*/ 1, /*unbackslash:*/ 0);
+ if (!pattern)
+ pattern = xstrdup(exp_word);
+ debug_printf_varexp("pattern:'%s'->'%s'\n", exp_word, pattern);
+ *p++ = SPECIAL_VAR_SYMBOL;
+ exp_word = p;
+ p = strchr(p, SPECIAL_VAR_SYMBOL);
+ *p = '\0';
+ repl = encode_then_expand_vararg(exp_word, /*handle_squotes:*/ 1, /*unbackslash:*/ 1);
+ debug_printf_varexp("repl:'%s'->'%s'\n", exp_word, repl);
+ /* HACK ALERT. We depend here on the fact that
+ * G.global_argv and results of utoa and get_local_var_value
+ * are actually in writable memory:
+ * replace_pattern momentarily stores NULs there. */
+ t = (char*)val;
+ to_be_freed = replace_pattern(t,
+ pattern,
+ (repl ? repl : exp_word),
+ exp_op);
+ if (to_be_freed) /* at least one replace happened */
+ val = to_be_freed;
+ free(pattern);
+ free(repl);
+ } else {
+ /* Unset variable always gives nothing */
+ // a=; echo ${a/*/w} # "w"
+ // unset a; echo ${a/*/w} # ""
+ /* Just skip "replace" part */
+ *p++ = SPECIAL_VAR_SYMBOL;
+ p = strchr(p, SPECIAL_VAR_SYMBOL);
+ *p = '\0';
+ }
+ }
+#endif /* BASH_PATTERN_SUBST */
+ else if (exp_op == ':') {
+#if BASH_SUBSTR && ENABLE_FEATURE_SH_MATH
+ /* It's ${var:N[:M]} bashism.
+ * Note that in encoded form it has TWO parts:
+ * var:N<SPECIAL_VAR_SYMBOL>M<SPECIAL_VAR_SYMBOL>
+ */
+ arith_t beg, len;
+ unsigned vallen;
+ const char *errmsg;
+
+ beg = expand_and_evaluate_arith(exp_word, &errmsg);
+ if (errmsg)
+ goto empty_result;
+ debug_printf_varexp("beg:'%s'=%lld\n", exp_word, (long long)beg);
+ *p++ = SPECIAL_VAR_SYMBOL;
+ exp_word = p;
+ p = strchr(p, SPECIAL_VAR_SYMBOL);
+ *p = '\0';
+ vallen = val ? strlen(val) : 0;
+ if (beg < 0) {
+ /* negative beg counts from the end */
+ beg = (arith_t)vallen + beg;
+ }
+ /* If expansion will be empty, do not even evaluate len */
+ if (!val || beg < 0 || beg > vallen) {
+ /* Why > vallen, not >=? bash:
+ * unset b; a=ab; : ${a:2:${b=3}}; echo $b # "", b=3 (!!!)
+ * unset b; a=a; : ${a:2:${b=3}}; echo $b # "", b not set
+ */
+ goto empty_result;
+ }
+ len = expand_and_evaluate_arith(exp_word, &errmsg);
+ if (errmsg)
+ goto empty_result;
+ debug_printf_varexp("len:'%s'=%lld\n", exp_word, (long long)len);
+ debug_printf_varexp("from val:'%s'\n", val);
+ if (len < 0) {
+ /* in bash, len=-n means strlen()-n */
+ len = (arith_t)vallen - beg + len;
+ if (len < 0) /* bash compat */
+ msg_and_die_if_script("%s: substring expression < 0", var);
+ }
+ if (len <= 0 || !val /*|| beg >= vallen*/) {
+ empty_result:
+ val = NULL;
+ } else {
+ /* Paranoia. What if user entered 9999999999999
+ * which fits in arith_t but not int? */
+ if (len > INT_MAX)
+ len = INT_MAX;
+ val = to_be_freed = xstrndup(val + beg, len);
+ }
+ debug_printf_varexp("val:'%s'\n", val);
+#else /* not (HUSH_SUBSTR_EXPANSION && FEATURE_SH_MATH) */
+ msg_and_die_if_script("malformed ${%s:...}", var);
+ val = NULL;
+#endif
+ } else { /* one of "-=+?" */
+ /* Standard-mandated substitution ops:
+ * ${var?word} - indicate error if unset
+ * If var is unset, word (or a message indicating it is unset
+ * if word is null) is written to standard error
+ * and the shell exits with a non-zero exit status.
+ * Otherwise, the value of var is substituted.
+ * ${var-word} - use default value
+ * If var is unset, word is substituted.
+ * ${var=word} - assign and use default value
+ * If var is unset, word is assigned to var.
+ * In all cases, final value of var is substituted.
+ * ${var+word} - use alternative value
+ * If var is unset, null is substituted.
+ * Otherwise, word is substituted.
+ *
+ * Word is subjected to tilde expansion, parameter expansion,
+ * command substitution, and arithmetic expansion.
+ * If word is not needed, it is not expanded.
+ *
+ * Colon forms (${var:-word}, ${var:=word} etc) do the same,
+ * but also treat null var as if it is unset.
+ *
+ * Word-splitting and single quote behavior:
+ *
+ * $ f() { for i; do echo "|$i|"; done; }
+ *
+ * $ x=; f ${x:?'x y' z}; echo $?
+ * bash: x: x y z # neither f nor "echo $?" executes
+ * (if interactive, bash does not exit, but merely aborts to prompt. $? is set to 1)
+ * $ x=; f "${x:?'x y' z}"
+ * bash: x: x y z # dash prints: dash: x: 'x y' z
+ *
+ * $ x=; f ${x:='x y' z}
+ * |x|
+ * |y|
+ * |z|
+ * $ x=; f "${x:='x y' z}"
+ * |'x y' z|
+ *
+ * $ x=x; f ${x:+'x y' z}
+ * |x y|
+ * |z|
+ * $ x=x; f "${x:+'x y' z}"
+ * |'x y' z|
+ *
+ * $ x=; f ${x:-'x y' z}
+ * |x y|
+ * |z|
+ * $ x=; f "${x:-'x y' z}"
+ * |'x y' z|
+ */
+ int use_word = (!val || ((exp_save == ':') && !val[0]));
+ if (exp_op == '+')
+ use_word = !use_word;
+ debug_printf_expand("expand: op:%c (null:%s) test:%i\n", exp_op,
+ (exp_save == ':') ? "true" : "false", use_word);
+ if (use_word) {
+ if (exp_op == '+' || exp_op == '-') {
+ /* ${var+word} - use alternative value */
+ /* ${var-word} - use default value */
+ n = encode_then_append_var_plusminus(output, n, exp_word,
+ /*dquoted:*/ (arg0 & 0x80)
+ );
+ val = NULL;
+ } else {
+ /* ${var?word} - indicate error if unset */
+ /* ${var=word} - assign and use default value */
+ to_be_freed = encode_then_expand_vararg(exp_word,
+ /*handle_squotes:*/ !(arg0 & 0x80),
+ /*unbackslash:*/ 0
+ );
+ if (to_be_freed)
+ exp_word = to_be_freed;
+ if (exp_op == '?') {
+ /* mimic bash message */
+ msg_and_die_if_script("%s: %s",
+ var,
+ exp_word[0]
+ ? exp_word
+ : "parameter null or not set"
+ /* ash has more specific messages, a-la: */
+ /*: (exp_save == ':' ? "parameter null or not set" : "parameter not set")*/
+ );
+//TODO: how interactive bash aborts expansion mid-command?
+//It aborts the entire line, returns to prompt:
+// $ f() { for i; do echo "|$i|"; done; }; x=; f "${x:?'x y' z}"; echo YO
+// bash: x: x y z
+// $
+// ("echo YO" is not executed, neither the f function call)
+ } else {
+ val = exp_word;
+ }
+ if (exp_op == '=') {
+ /* ${var=[word]} or ${var:=[word]} */
+ if (isdigit(var[0]) || var[0] == '#') {
+ /* mimic bash message */
+ msg_and_die_if_script("$%s: cannot assign in this way", var);
+ val = NULL;
+ } else {
+ char *new_var = xasprintf("%s=%s", var, val);
+ set_local_var(new_var, /*flag:*/ 0);
+ }
+ }
+ }
+ }
+ } /* one of "-=+?" */
+
+ *exp_saveptr = exp_save;
+ } /* if (exp_op) */
+
+ arg[0] = arg0;
+ *pp = p;
+
+ n = append_str_maybe_ifs_split(output, n, first_ch, val);
+
+ free(to_be_freed);
+ return n;
+}
+
+/* Expand all variable references in given string, adding words to list[]
+ * at n, n+1,... positions. Return updated n (so that list[n] is next one
+ * to be filled). This routine is extremely tricky: has to deal with
+ * variables/parameters with whitespace, $* and $@, and constructs like
+ * 'echo -$*-'. If you play here, you must run testsuite afterwards! */
+static NOINLINE int expand_vars_to_list(o_string *output, int n, char *arg)
+{
+ /* output->o_expflags & EXP_FLAG_SINGLEWORD (0x80) if we are in
+ * expansion of right-hand side of assignment == 1-element expand.
+ */
+ char cant_be_null = 0; /* only bit 0x80 matters */
+ char *p;
+
+ debug_printf_expand("expand_vars_to_list: arg:'%s' singleword:%x\n", arg,
+ !!(output->o_expflags & EXP_FLAG_SINGLEWORD));
+ debug_print_list("expand_vars_to_list[0]", output, n);
+
+ while ((p = strchr(arg, SPECIAL_VAR_SYMBOL)) != NULL) {
+ char first_ch;
+#if ENABLE_FEATURE_SH_MATH
+ char arith_buf[sizeof(arith_t)*3 + 2];
+#endif
+
+ if (output->ended_in_ifs) {
+ o_addchr(output, '\0');
+ n = o_save_ptr(output, n);
+ output->ended_in_ifs = 0;
+ }
+
+ o_addblock(output, arg, p - arg);
+ debug_print_list("expand_vars_to_list[1]", output, n);
+ arg = ++p;
+ p = strchr(p, SPECIAL_VAR_SYMBOL);
+
+ /* Fetch special var name (if it is indeed one of them)
+ * and quote bit, force the bit on if singleword expansion -
+ * important for not getting v=$@ expand to many words. */
+ first_ch = arg[0] | (output->o_expflags & EXP_FLAG_SINGLEWORD);
+
+ /* Is this variable quoted and thus expansion can't be null?
+ * "$@" is special. Even if quoted, it can still
+ * expand to nothing (not even an empty string),
+ * thus it is excluded. */
+ if ((first_ch & 0x7f) != '@')
+ cant_be_null |= first_ch;
+
+ switch (first_ch & 0x7f) {
+ /* Highest bit in first_ch indicates that var is double-quoted */
+ case '*':
+ case '@': {
+ int i;
+ if (!G.global_argv[1])
+ break;
+ i = 1;
+ cant_be_null |= first_ch; /* do it for "$@" _now_, when we know it's not empty */
+ if (!(first_ch & 0x80)) { /* unquoted $* or $@ */
+ while (G.global_argv[i]) {
+ n = expand_on_ifs(output, n, G.global_argv[i]);
+ debug_printf_expand("expand_vars_to_list: argv %d (last %d)\n", i, G.global_argc - 1);
+ if (G.global_argv[i++][0] && G.global_argv[i]) {
+ /* this argv[] is not empty and not last:
+ * put terminating NUL, start new word */
+ o_addchr(output, '\0');
+ debug_print_list("expand_vars_to_list[2]", output, n);
+ n = o_save_ptr(output, n);
+ debug_print_list("expand_vars_to_list[3]", output, n);
+ }
+ }
+ } else
+ /* If EXP_FLAG_SINGLEWORD, we handle assignment 'a=....$@.....'
+ * and in this case should treat it like '$*' - see 'else...' below */
+ if (first_ch == (char)('@'|0x80) /* quoted $@ */
+ && !(output->o_expflags & EXP_FLAG_SINGLEWORD) /* not v="$@" case */
+ ) {
+ while (1) {
+ o_addQstr(output, G.global_argv[i]);
+ if (++i >= G.global_argc)
+ break;
+ o_addchr(output, '\0');
+ debug_print_list("expand_vars_to_list[4]", output, n);
+ n = o_save_ptr(output, n);
+ }
+ } else { /* quoted $* (or v="$@" case): add as one word */
+ while (1) {
+ o_addQstr(output, G.global_argv[i]);
+ if (!G.global_argv[++i])
+ break;
+ if (G.ifs[0])
+ o_addchr(output, G.ifs[0]);
+ }
+ output->has_quoted_part = 1;
+ }
+ break;
+ }
+ case SPECIAL_VAR_SYMBOL: {
+ /* <SPECIAL_VAR_SYMBOL><SPECIAL_VAR_SYMBOL> */
+ /* "Empty variable", used to make "" etc to not disappear */
+ output->has_quoted_part = 1;
+ cant_be_null = 0x80;
+ arg++;
+ break;
+ }
+ case SPECIAL_VAR_QUOTED_SVS:
+ /* <SPECIAL_VAR_SYMBOL><SPECIAL_VAR_QUOTED_SVS><SPECIAL_VAR_SYMBOL> */
+ /* "^C variable", represents literal ^C char (possible in scripts) */
+ o_addchr(output, SPECIAL_VAR_SYMBOL);
+ arg++;
+ break;
+#if ENABLE_HUSH_TICK
+ case '`': {
+ /* <SPECIAL_VAR_SYMBOL>`cmd<SPECIAL_VAR_SYMBOL> */
+ o_string subst_result = NULL_O_STRING;
+
+ *p = '\0'; /* replace trailing <SPECIAL_VAR_SYMBOL> */
+ arg++;
+ /* Can't just stuff it into output o_string,
+ * expanded result may need to be globbed
+ * and $IFS-split */
+ debug_printf_subst("SUBST '%s' first_ch %x\n", arg, first_ch);
+ G.last_exitcode = process_command_subs(&subst_result, arg);
+ G.expand_exitcode = G.last_exitcode;
+ debug_printf_subst("SUBST RES:%d '%s'\n", G.last_exitcode, subst_result.data);
+ n = append_str_maybe_ifs_split(output, n, first_ch, subst_result.data);
+ o_free(&subst_result);
+ break;
+ }
+#endif
+#if ENABLE_FEATURE_SH_MATH
+ case '+': {
+ /* <SPECIAL_VAR_SYMBOL>+arith<SPECIAL_VAR_SYMBOL> */
+ arith_t res;
+
+ arg++; /* skip '+' */
+ *p = '\0'; /* replace trailing <SPECIAL_VAR_SYMBOL> */
+ debug_printf_subst("ARITH '%s' first_ch %x\n", arg, first_ch);
+ res = expand_and_evaluate_arith(arg, NULL);
+ debug_printf_subst("ARITH RES '"ARITH_FMT"'\n", res);
+ sprintf(arith_buf, ARITH_FMT, res);
+ if (res < 0
+ && first_ch == (char)('+'|0x80)
+ /* && (output->o_expflags & EXP_FLAG_ESC_GLOB_CHARS) */
+ ) {
+ /* Quoted negative ariths, like filename[0"$((-9))"],
+ * should not be interpreted as glob ranges.
+ * Convert leading '-' to '\-':
+ */
+ o_grow_by(output, 1);
+ output->data[output->length++] = '\\';
+ }
+ o_addstr(output, arith_buf);
+ break;
+ }
+#endif
+ default:
+ /* <SPECIAL_VAR_SYMBOL>varname[ops]<SPECIAL_VAR_SYMBOL> */
+ n = expand_one_var(output, n, first_ch, arg, &p);
+ break;
+ } /* switch (char after <SPECIAL_VAR_SYMBOL>) */
+
+ /* Restore NULL'ed SPECIAL_VAR_SYMBOL.
+ * Do the check to avoid writing to a const string. */
+ if (*p != SPECIAL_VAR_SYMBOL)
+ *p = SPECIAL_VAR_SYMBOL;
+ arg = ++p;
+ } /* end of "while (SPECIAL_VAR_SYMBOL is found) ..." */
+
+ if (*arg) {
+ /* handle trailing string */
+ if (output->ended_in_ifs) {
+ o_addchr(output, '\0');
+ n = o_save_ptr(output, n);
+ }
+ debug_print_list("expand_vars_to_list[a]", output, n);
+ /* this part is literal, and it was already pre-quoted
+ * if needed (much earlier), do not use o_addQstr here!
+ */
+ o_addstr(output, arg);
+ debug_print_list("expand_vars_to_list[b]", output, n);
+ } else
+ if (output->length == o_get_last_ptr(output, n) /* expansion is empty */
+ && !(cant_be_null & 0x80) /* and all vars were not quoted */
+ && !output->has_quoted_part
+ ) {
+ n--;
+ /* allow to reuse list[n] later without re-growth */
+ output->has_empty_slot = 1;
+ }
+
+ return n;
+}
+
+static char **expand_variables(char **argv, unsigned expflags)
+{
+ int n;
+ char **list;
+ o_string output = NULL_O_STRING;
+
+ output.o_expflags = expflags;
+
+ n = 0;
+ for (;;) {
+ /* go to next list[n] */
+ output.ended_in_ifs = 0;
+ n = o_save_ptr(&output, n);
+
+ if (!*argv)
+ break;
+
+ /* expand argv[i] */
+ n = expand_vars_to_list(&output, n, *argv++);
+ /* if (!output->has_empty_slot) -- need this?? */
+ o_addchr(&output, '\0');
+ }
+ debug_print_list("expand_variables", &output, n);
+
+ /* output.data (malloced in one block) gets returned in "list" */
+ list = o_finalize_list(&output, n);
+ debug_print_strings("expand_variables[1]", list);
+ return list;
+}
+
+static char **expand_strvec_to_strvec(char **argv)
+{
+ return expand_variables(argv, EXP_FLAG_GLOB | EXP_FLAG_ESC_GLOB_CHARS);
+}
+
+#if defined(CMD_SINGLEWORD_NOGLOB) || defined(CMD_TEST2_SINGLEWORD_NOGLOB)
+static char **expand_strvec_to_strvec_singleword_noglob(char **argv)
+{
+ return expand_variables(argv, EXP_FLAG_SINGLEWORD);
+}
+#endif
+
+/* Used for expansion of right hand of assignments,
+ * $((...)), heredocs, variable expansion parts.
+ *
+ * NB: should NOT do globbing!
+ * "export v=/bin/c*; env | grep ^v=" outputs "v=/bin/c*"
+ */
+static char *expand_string_to_string(const char *str, int EXP_flags, int do_unbackslash)
+{
+#if !BASH_PATTERN_SUBST && !ENABLE_HUSH_CASE
+ const int do_unbackslash = 1;
+ const int EXP_flags = EXP_FLAG_ESC_GLOB_CHARS;
+#endif
+ char *argv[2], **list;
+
+ debug_printf_expand("string_to_string<='%s'\n", str);
+ /* This is generally an optimization, but it also
+ * handles "", which otherwise trips over !list[0] check below.
+ * (is this ever happens that we actually get str="" here?)
+ */
+ if (!strchr(str, SPECIAL_VAR_SYMBOL) && !strchr(str, '\\')) {
+ //TODO: Can use on strings with \ too, just unbackslash() them?
+ debug_printf_expand("string_to_string(fast)=>'%s'\n", str);
+ return xstrdup(str);
+ }
+
+ argv[0] = (char*)str;
+ argv[1] = NULL;
+ list = expand_variables(argv, EXP_flags | EXP_FLAG_SINGLEWORD);
+ if (!list[0]) {
+ /* Example where it happens:
+ * x=; echo ${x:-"$@"}
+ */
+ ((char*)list)[0] = '\0';
+ } else {
+ if (HUSH_DEBUG)
+ if (list[1])
+ bb_simple_error_msg_and_die("BUG in varexp2");
+ /* actually, just move string 2*sizeof(char*) bytes back */
+ overlapping_strcpy((char*)list, list[0]);
+ if (do_unbackslash)
+ unbackslash((char*)list);
+ }
+ debug_printf_expand("string_to_string=>'%s'\n", (char*)list);
+ return (char*)list;
+}
+
+#if 0
+static char* expand_strvec_to_string(char **argv)
+{
+ char **list;
+
+ list = expand_variables(argv, EXP_FLAG_SINGLEWORD);
+ /* Convert all NULs to spaces */
+ if (list[0]) {
+ int n = 1;
+ while (list[n]) {
+ if (HUSH_DEBUG)
+ if (list[n-1] + strlen(list[n-1]) + 1 != list[n])
+ bb_error_msg_and_die("BUG in varexp3");
+ /* bash uses ' ' regardless of $IFS contents */
+ list[n][-1] = ' ';
+ n++;
+ }
+ }
+ overlapping_strcpy((char*)list, list[0] ? list[0] : "");
+ debug_printf_expand("strvec_to_string='%s'\n", (char*)list);
+ return (char*)list;
+}
+#endif
+
+static char **expand_assignments(char **argv, int count)
+{
+ int i;
+ char **p;
+
+ G.expanded_assignments = p = NULL;
+ /* Expand assignments into one string each */
+ for (i = 0; i < count; i++) {
+ p = add_string_to_strings(p,
+ expand_string_to_string(argv[i],
+ EXP_FLAG_ESC_GLOB_CHARS,
+ /*unbackslash:*/ 1
+ )
+ );
+ G.expanded_assignments = p;
+ }
+ G.expanded_assignments = NULL;
+ return p;
+}
+
+
+static void switch_off_special_sigs(unsigned mask)
+{
+ unsigned sig = 0;
+ while ((mask >>= 1) != 0) {
+ sig++;
+ if (!(mask & 1))
+ continue;
+#if ENABLE_HUSH_TRAP
+ if (G_traps) {
+ if (G_traps[sig] && !G_traps[sig][0])
+ /* trap is '', has to remain SIG_IGN */
+ continue;
+ free(G_traps[sig]);
+ G_traps[sig] = NULL;
+ }
+#endif
+ /* We are here only if no trap or trap was not '' */
+ install_sighandler(sig, SIG_DFL);
+ }
+}
+
+#if BB_MMU
+/* never called */
+void re_execute_shell(char ***to_free, const char *s,
+ char *g_argv0, char **g_argv,
+ char **builtin_argv) NORETURN;
+
+static void reset_traps_to_defaults(void)
+{
+ /* This function is always called in a child shell
+ * after fork (not vfork, NOMMU doesn't use this function).
+ */
+ IF_HUSH_TRAP(unsigned sig;)
+ unsigned mask;
+
+ /* Child shells are not interactive.
+ * SIGTTIN/SIGTTOU/SIGTSTP should not have special handling.
+ * Testcase: (while :; do :; done) + ^Z should background.
+ * Same goes for SIGTERM, SIGHUP, SIGINT.
+ */
+ mask = (G.special_sig_mask & SPECIAL_INTERACTIVE_SIGS) | G_fatal_sig_mask;
+ if (!G_traps && !mask)
+ return; /* already no traps and no special sigs */
+
+ /* Switch off special sigs */
+ switch_off_special_sigs(mask);
+# if ENABLE_HUSH_JOB
+ G_fatal_sig_mask = 0;
+# endif
+ G.special_sig_mask &= ~SPECIAL_INTERACTIVE_SIGS;
+ /* SIGQUIT,SIGCHLD and maybe SPECIAL_JOBSTOP_SIGS
+ * remain set in G.special_sig_mask */
+
+# if ENABLE_HUSH_TRAP
+ if (!G_traps)
+ return;
+
+ /* Reset all sigs to default except ones with empty traps */
+ for (sig = 0; sig < NSIG; sig++) {
+ if (!G_traps[sig])
+ continue; /* no trap: nothing to do */
+ if (!G_traps[sig][0])
+ continue; /* empty trap: has to remain SIG_IGN */
+ /* sig has non-empty trap, reset it: */
+ free(G_traps[sig]);
+ G_traps[sig] = NULL;
+ /* There is no signal for trap 0 (EXIT) */
+ if (sig == 0)
+ continue;
+ install_sighandler(sig, pick_sighandler(sig));
+ }
+# endif
+}
+
+#else /* !BB_MMU */
+
+static void re_execute_shell(char ***to_free, const char *s,
+ char *g_argv0, char **g_argv,
+ char **builtin_argv) NORETURN;
+static void re_execute_shell(char ***to_free, const char *s,
+ char *g_argv0, char **g_argv,
+ char **builtin_argv)
+{
+# define NOMMU_HACK_FMT ("-$%x:%x:%x:%x:%x:%llx" IF_HUSH_LOOPS(":%x"))
+ /* delims + 2 * (number of bytes in printed hex numbers) */
+ char param_buf[sizeof(NOMMU_HACK_FMT) + 2 * (sizeof(int)*6 + sizeof(long long)*1)];
+ char *heredoc_argv[4];
+ struct variable *cur;
+# if ENABLE_HUSH_FUNCTIONS
+ struct function *funcp;
+# endif
+ char **argv, **pp;
+ unsigned cnt;
+ unsigned long long empty_trap_mask;
+
+ if (!g_argv0) { /* heredoc */
+ argv = heredoc_argv;
+ argv[0] = (char *) G.argv0_for_re_execing;
+ argv[1] = (char *) "-<";
+ argv[2] = (char *) s;
+ argv[3] = NULL;
+ pp = &argv[3]; /* used as pointer to empty environment */
+ goto do_exec;
+ }
+
+ cnt = 0;
+ pp = builtin_argv;
+ if (pp) while (*pp++)
+ cnt++;
+
+ empty_trap_mask = 0;
+ if (G_traps) {
+ int sig;
+ for (sig = 1; sig < NSIG; sig++) {
+ if (G_traps[sig] && !G_traps[sig][0])
+ empty_trap_mask |= 1LL << sig;
+ }
+ }
+
+ sprintf(param_buf, NOMMU_HACK_FMT
+ , (unsigned) G.root_pid
+ , (unsigned) G.root_ppid
+ , (unsigned) G.last_bg_pid
+ , (unsigned) G.last_exitcode
+ , cnt
+ , empty_trap_mask
+ IF_HUSH_LOOPS(, G.depth_of_loop)
+ );
+# undef NOMMU_HACK_FMT
+ /* 1:hush 2:-$<pid>:<pid>:<exitcode>:<etc...> <vars...> <funcs...>
+ * 3:-c 4:<cmd> 5:<arg0> <argN...> 6:NULL
+ */
+ cnt += 6;
+ for (cur = G.top_var; cur; cur = cur->next) {
+ if (!cur->flg_export || cur->flg_read_only)
+ cnt += 2;
+ }
+# if ENABLE_HUSH_FUNCTIONS
+ for (funcp = G.top_func; funcp; funcp = funcp->next)
+ cnt += 3;
+# endif
+ pp = g_argv;
+ while (*pp++)
+ cnt++;
+ *to_free = argv = pp = xzalloc(sizeof(argv[0]) * cnt);
+ *pp++ = (char *) G.argv0_for_re_execing;
+ *pp++ = param_buf;
+ for (cur = G.top_var; cur; cur = cur->next) {
+ if (strcmp(cur->varstr, hush_version_str) == 0)
+ continue;
+ if (cur->flg_read_only) {
+ *pp++ = (char *) "-R";
+ *pp++ = cur->varstr;
+ } else if (!cur->flg_export) {
+ *pp++ = (char *) "-V";
+ *pp++ = cur->varstr;
+ }
+ }
+# if ENABLE_HUSH_FUNCTIONS
+ for (funcp = G.top_func; funcp; funcp = funcp->next) {
+ *pp++ = (char *) "-F";
+ *pp++ = funcp->name;
+ *pp++ = funcp->body_as_string;
+ }
+# endif
+ /* We can pass activated traps here. Say, -Tnn:trap_string
+ *
+ * However, POSIX says that subshells reset signals with traps
+ * to SIG_DFL.
+ * I tested bash-3.2 and it not only does that with true subshells
+ * of the form ( list ), but with any forked children shells.
+ * I set trap "echo W" WINCH; and then tried:
+ *
+ * { echo 1; sleep 20; echo 2; } &
+ * while true; do echo 1; sleep 20; echo 2; break; done &
+ * true | { echo 1; sleep 20; echo 2; } | cat
+ *
+ * In all these cases sending SIGWINCH to the child shell
+ * did not run the trap. If I add trap "echo V" WINCH;
+ * _inside_ group (just before echo 1), it works.
+ *
+ * I conclude it means we don't need to pass active traps here.
+ */
+ *pp++ = (char *) "-c";
+ *pp++ = (char *) s;
+ if (builtin_argv) {
+ while (*++builtin_argv)
+ *pp++ = *builtin_argv;
+ *pp++ = (char *) "";
+ }
+ *pp++ = g_argv0;
+ while (*g_argv)
+ *pp++ = *g_argv++;
+ /* *pp = NULL; - is already there */
+ pp = environ;
+
+ do_exec:
+ debug_printf_exec("re_execute_shell pid:%d cmd:'%s'\n", getpid(), s);
+ /* Don't propagate SIG_IGN to the child */
+ if (SPECIAL_JOBSTOP_SIGS != 0)
+ switch_off_special_sigs(G.special_sig_mask & SPECIAL_JOBSTOP_SIGS);
+ execve(bb_busybox_exec_path, argv, pp);
+ /* Fallback. Useful for init=/bin/hush usage etc */
+ if (argv[0][0] == '/')
+ execve(argv[0], argv, pp);
+ xfunc_error_retval = 127;
+ bb_simple_error_msg_and_die("can't re-execute the shell");
+}
+#endif /* !BB_MMU */
+
+
+static int run_and_free_list(struct pipe *pi);
+
+/* Executing from string: eval, sh -c '...'
+ * or from file: /etc/profile, . file, sh <script>, sh (intereactive)
+ * end_trigger controls how often we stop parsing
+ * NUL: parse all, execute, return
+ * ';': parse till ';' or newline, execute, repeat till EOF
+ */
+static void parse_and_run_stream(struct in_str *inp, int end_trigger)
+{
+ /* Why we need empty flag?
+ * An obscure corner case "false; ``; echo $?":
+ * empty command in `` should still set $? to 0.
+ * But we can't just set $? to 0 at the start,
+ * this breaks "false; echo `echo $?`" case.
+ */
+ bool empty = 1;
+ while (1) {
+ struct pipe *pipe_list;
+
+#if ENABLE_HUSH_INTERACTIVE
+ if (end_trigger == ';') {
+ G.promptmode = 0; /* PS1 */
+ debug_printf_prompt("%s promptmode=%d\n", __func__, G.promptmode);
+ }
+#endif
+ pipe_list = parse_stream(NULL, NULL, inp, end_trigger);
+ if (!pipe_list || pipe_list == ERR_PTR) { /* EOF/error */
+ /* If we are in "big" script
+ * (not in `cmd` or something similar)...
+ */
+ if (pipe_list == ERR_PTR && end_trigger == ';') {
+ /* Discard cached input (rest of line) */
+ int ch = inp->last_char;
+ while (ch != EOF && ch != '\n') {
+ //bb_error_msg("Discarded:'%c'", ch);
+ ch = i_getch(inp);
+ }
+ /* Force prompt */
+ inp->p = NULL;
+ /* This stream isn't empty */
+ empty = 0;
+ continue;
+ }
+ if (!pipe_list && empty)
+ G.last_exitcode = 0;
+ break;
+ }
+ debug_print_tree(pipe_list, 0);
+ debug_printf_exec("parse_and_run_stream: run_and_free_list\n");
+ run_and_free_list(pipe_list);
+ empty = 0;
+ if (G_flag_return_in_progress == 1)
+ break;
+ }
+}
+
+static void parse_and_run_string(const char *s)
+{
+ struct in_str input;
+ //IF_HUSH_LINENO_VAR(unsigned sv = G.parse_lineno;)
+
+ setup_string_in_str(&input, s);
+ parse_and_run_stream(&input, '\0');
+ //IF_HUSH_LINENO_VAR(G.parse_lineno = sv;)
+}
+
+static void parse_and_run_file(HFILE *fp)
+{
+ struct in_str input;
+ IF_HUSH_LINENO_VAR(unsigned sv = G.parse_lineno;)
+
+ IF_HUSH_LINENO_VAR(G.parse_lineno = 1;)
+ setup_file_in_str(&input, fp);
+ parse_and_run_stream(&input, ';');
+ IF_HUSH_LINENO_VAR(G.parse_lineno = sv;)
+}
+
+#if ENABLE_HUSH_TICK
+static int generate_stream_from_string(const char *s, pid_t *pid_p)
+{
+ pid_t pid;
+ int channel[2];
+# if !BB_MMU
+ char **to_free = NULL;
+# endif
+
+ xpipe(channel);
+ pid = BB_MMU ? xfork() : xvfork();
+ if (pid == 0) { /* child */
+ disable_restore_tty_pgrp_on_exit();
+ /* Process substitution is not considered to be usual
+ * 'command execution'.
+ * SUSv3 says ctrl-Z should be ignored, ctrl-C should not.
+ */
+ bb_signals(0
+ + (1 << SIGTSTP)
+ + (1 << SIGTTIN)
+ + (1 << SIGTTOU)
+ , SIG_IGN);
+ close(channel[0]); /* NB: close _first_, then move fd! */
+ xmove_fd(channel[1], 1);
+# if ENABLE_HUSH_TRAP
+ /* Awful hack for `trap` or $(trap).
+ *
+ * http://www.opengroup.org/onlinepubs/009695399/utilities/trap.html
+ * contains an example where "trap" is executed in a subshell:
+ *
+ * save_traps=$(trap)
+ * ...
+ * eval "$save_traps"
+ *
+ * Standard does not say that "trap" in subshell shall print
+ * parent shell's traps. It only says that its output
+ * must have suitable form, but then, in the above example
+ * (which is not supposed to be normative), it implies that.
+ *
+ * bash (and probably other shell) does implement it
+ * (traps are reset to defaults, but "trap" still shows them),
+ * but as a result, "trap" logic is hopelessly messed up:
+ *
+ * # trap
+ * trap -- 'echo Ho' SIGWINCH <--- we have a handler
+ * # (trap) <--- trap is in subshell - no output (correct, traps are reset)
+ * # true | trap <--- trap is in subshell - no output (ditto)
+ * # echo `true | trap` <--- in subshell - output (but traps are reset!)
+ * trap -- 'echo Ho' SIGWINCH
+ * # echo `(trap)` <--- in subshell in subshell - output
+ * trap -- 'echo Ho' SIGWINCH
+ * # echo `true | (trap)` <--- in subshell in subshell in subshell - output!
+ * trap -- 'echo Ho' SIGWINCH
+ *
+ * The rules when to forget and when to not forget traps
+ * get really complex and nonsensical.
+ *
+ * Our solution: ONLY bare $(trap) or `trap` is special.
+ */
+ s = skip_whitespace(s);
+ if (is_prefixed_with(s, "trap")
+ && skip_whitespace(s + 4)[0] == '\0'
+ ) {
+ static const char *const argv[] = { NULL, NULL };
+ builtin_trap((char**)argv);
+ fflush_all(); /* important */
+ _exit(0);
+ }
+# endif
+# if BB_MMU
+ /* Prevent it from trying to handle ctrl-z etc */
+ IF_HUSH_JOB(G.run_list_level = 1;)
+ CLEAR_RANDOM_T(&G.random_gen); /* or else $RANDOM repeats in child */
+ reset_traps_to_defaults();
+ IF_HUSH_MODE_X(G.x_mode_depth++;)
+ //bb_error_msg("%s: ++x_mode_depth=%d", __func__, G.x_mode_depth);
+ parse_and_run_string(s);
+ _exit(G.last_exitcode);
+# else
+ /* We re-execute after vfork on NOMMU. This makes this script safe:
+ * yes "0123456789012345678901234567890" | dd bs=32 count=64k >BIG
+ * huge=`cat BIG` # was blocking here forever
+ * echo OK
+ */
+ re_execute_shell(&to_free,
+ s,
+ G.global_argv[0],
+ G.global_argv + 1,
+ NULL);
+# endif
+ }
+
+ /* parent */
+ *pid_p = pid;
+# if ENABLE_HUSH_FAST
+ G.count_SIGCHLD++;
+//bb_error_msg("[%d] fork in generate_stream_from_string:"
+// " G.count_SIGCHLD:%d G.handled_SIGCHLD:%d",
+// getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
+# endif
+ enable_restore_tty_pgrp_on_exit();
+# if !BB_MMU
+ free(to_free);
+# endif
+ close(channel[1]);
+ return channel[0];
+}
+
+/* Return code is exit status of the process that is run. */
+static int process_command_subs(o_string *dest, const char *s)
+{
+ FILE *fp;
+ pid_t pid;
+ int status, ch, eol_cnt;
+
+ fp = xfdopen_for_read(generate_stream_from_string(s, &pid));
+
+ /* Now send results of command back into original context */
+ eol_cnt = 0;
+ while ((ch = getc(fp)) != EOF) {
+ if (ch == '\0')
+ continue;
+ if (ch == '\n') {
+ eol_cnt++;
+ continue;
+ }
+ while (eol_cnt) {
+ o_addchr(dest, '\n');
+ eol_cnt--;
+ }
+ o_addQchr(dest, ch);
+ }
+
+ debug_printf("done reading from `cmd` pipe, closing it\n");
+ fclose(fp);
+ /* We need to extract exitcode. Test case
+ * "true; echo `sleep 1; false` $?"
+ * should print 1 */
+ safe_waitpid(pid, &status, 0);
+ debug_printf("child exited. returning its exitcode:%d\n", WEXITSTATUS(status));
+ return WEXITSTATUS(status);
+}
+#endif /* ENABLE_HUSH_TICK */
+
+
+static void setup_heredoc(struct redir_struct *redir)
+{
+ struct fd_pair pair;
+ pid_t pid;
+ int len, written;
+ /* the _body_ of heredoc (misleading field name) */
+ const char *heredoc = redir->rd_filename;
+ char *expanded;
+#if !BB_MMU
+ char **to_free;
+#endif
+
+ expanded = NULL;
+ if (!(redir->rd_dup & HEREDOC_QUOTED)) {
+ expanded = encode_then_expand_string(heredoc);
+ if (expanded)
+ heredoc = expanded;
+ }
+ len = strlen(heredoc);
+
+ close(redir->rd_fd); /* often saves dup2+close in xmove_fd */
+ xpiped_pair(pair);
+ xmove_fd(pair.rd, redir->rd_fd);
+
+ /* Try writing without forking. Newer kernels have
+ * dynamically growing pipes. Must use non-blocking write! */
+ ndelay_on(pair.wr);
+ while (1) {
+ written = write(pair.wr, heredoc, len);
+ if (written <= 0)
+ break;
+ len -= written;
+ if (len == 0) {
+ close(pair.wr);
+ free(expanded);
+ return;
+ }
+ heredoc += written;
+ }
+ ndelay_off(pair.wr);
+
+ /* Okay, pipe buffer was not big enough */
+ /* Note: we must not create a stray child (bastard? :)
+ * for the unsuspecting parent process. Child creates a grandchild
+ * and exits before parent execs the process which consumes heredoc
+ * (that exec happens after we return from this function) */
+#if !BB_MMU
+ to_free = NULL;
+#endif
+ pid = xvfork();
+ if (pid == 0) {
+ /* child */
+ disable_restore_tty_pgrp_on_exit();
+ pid = BB_MMU ? xfork() : xvfork();
+ if (pid != 0)
+ _exit(0);
+ /* grandchild */
+ close(redir->rd_fd); /* read side of the pipe */
+#if BB_MMU
+ full_write(pair.wr, heredoc, len); /* may loop or block */
+ _exit(0);
+#else
+ /* Delegate blocking writes to another process */
+ xmove_fd(pair.wr, STDOUT_FILENO);
+ re_execute_shell(&to_free, heredoc, NULL, NULL, NULL);
+#endif
+ }
+ /* parent */
+#if ENABLE_HUSH_FAST
+ G.count_SIGCHLD++;
+//bb_error_msg("[%d] fork in setup_heredoc: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
+#endif
+ enable_restore_tty_pgrp_on_exit();
+#if !BB_MMU
+ free(to_free);
+#endif
+ close(pair.wr);
+ free(expanded);
+ wait(NULL); /* wait till child has died */
+}
+
+struct squirrel {
+ int orig_fd;
+ int moved_to;
+ /* moved_to = n: fd was moved to n; restore back to orig_fd after redir */
+ /* moved_to = -1: fd was opened by redirect; close orig_fd after redir */
+};
+
+static struct squirrel *append_squirrel(struct squirrel *sq, int i, int orig, int moved)
+{
+ sq = xrealloc(sq, (i + 2) * sizeof(sq[0]));
+ sq[i].orig_fd = orig;
+ sq[i].moved_to = moved;
+ sq[i+1].orig_fd = -1; /* end marker */
+ return sq;
+}
+
+static struct squirrel *add_squirrel(struct squirrel *sq, int fd, int avoid_fd)
+{
+ int moved_to;
+ int i;
+
+ i = 0;
+ if (sq) for (; sq[i].orig_fd >= 0; i++) {
+ /* If we collide with an already moved fd... */
+ if (fd == sq[i].moved_to) {
+ sq[i].moved_to = dup_CLOEXEC(sq[i].moved_to, avoid_fd);
+ debug_printf_redir("redirect_fd %d: already busy, moving to %d\n", fd, sq[i].moved_to);
+ if (sq[i].moved_to < 0) /* what? */
+ xfunc_die();
+ return sq;
+ }
+ if (fd == sq[i].orig_fd) {
+ /* Example: echo Hello >/dev/null 1>&2 */
+ debug_printf_redir("redirect_fd %d: already moved\n", fd);
+ return sq;
+ }
+ }
+
+ /* If this fd is open, we move and remember it; if it's closed, moved_to = -1 */
+ moved_to = dup_CLOEXEC(fd, avoid_fd);
+ debug_printf_redir("redirect_fd %d: previous fd is moved to %d (-1 if it was closed)\n", fd, moved_to);
+ if (moved_to < 0 && errno != EBADF)
+ xfunc_die();
+ return append_squirrel(sq, i, fd, moved_to);
+}
+
+static struct squirrel *add_squirrel_closed(struct squirrel *sq, int fd)
+{
+ int i;
+
+ i = 0;
+ if (sq) for (; sq[i].orig_fd >= 0; i++) {
+ /* If we collide with an already moved fd... */
+ if (fd == sq[i].orig_fd) {
+ /* Examples:
+ * "echo 3>FILE 3>&- 3>FILE"
+ * "echo 3>&- 3>FILE"
+ * No need for last redirect to insert
+ * another "need to close 3" indicator.
+ */
+ debug_printf_redir("redirect_fd %d: already moved or closed\n", fd);
+ return sq;
+ }
+ }
+
+ debug_printf_redir("redirect_fd %d: previous fd was closed\n", fd);
+ return append_squirrel(sq, i, fd, -1);
+}
+
+/* fd: redirect wants this fd to be used (e.g. 3>file).
+ * Move all conflicting internally used fds,
+ * and remember them so that we can restore them later.
+ */
+static int save_fd_on_redirect(int fd, int avoid_fd, struct squirrel **sqp)
+{
+ if (avoid_fd < 9) /* the important case here is that it can be -1 */
+ avoid_fd = 9;
+
+#if ENABLE_HUSH_INTERACTIVE
+ if (fd != 0 /* don't trigger for G_interactive_fd == 0 (that's "not interactive" flag) */
+ && fd == G_interactive_fd
+ ) {
+ /* Testcase: "ls -l /proc/$$/fd 255>&-" should work */
+ G_interactive_fd = xdup_CLOEXEC_and_close(G_interactive_fd, avoid_fd);
+ debug_printf_redir("redirect_fd %d: matches interactive_fd, moving it to %d\n", fd, G_interactive_fd);
+ return 1; /* "we closed fd" */
+ }
+#endif
+ /* Are we called from setup_redirects(squirrel==NULL)
+ * in redirect in a [v]forked child?
+ */
+ if (sqp == NULL) {
+ /* No need to move script fds.
+ * For NOMMU case, it's actively wrong: we'd change ->fd
+ * fields in memory for the parent, but parent's fds
+ * aren't moved, it would use wrong fd!
+ * Reproducer: "cmd 3>FILE" in script.
+ * If we would call move_HFILEs_on_redirect(), child would:
+ * fcntl64(3, F_DUPFD_CLOEXEC, 10) = 10
+ * close(3) = 0
+ * and change ->fd to 10 if fd#3 is a script fd. WRONG.
+ */
+ //bb_error_msg("sqp == NULL: [v]forked child");
+ return 0;
+ }
+
+ /* If this one of script's fds? */
+ if (move_HFILEs_on_redirect(fd, avoid_fd))
+ return 1; /* yes. "we closed fd" (actually moved it) */
+
+ /* Are we called for "exec 3>FILE"? Came through
+ * redirect_and_varexp_helper(squirrel=ERR_PTR) -> setup_redirects(ERR_PTR)
+ * This case used to fail for this script:
+ * exec 3>FILE
+ * echo Ok
+ * ...100000 more lines...
+ * echo Ok
+ * as follows:
+ * read(3, "exec 3>FILE\necho Ok\necho Ok"..., 1024) = 1024
+ * open("FILE", O_WRONLY|O_CREAT|O_TRUNC|O_LARGEFILE, 0666) = 4
+ * dup2(4, 3) = 3
+ * ^^^^^^^^ oops, we lost fd#3 opened to our script!
+ * close(4) = 0
+ * write(1, "Ok\n", 3) = 3
+ * ... = 3
+ * write(1, "Ok\n", 3) = 3
+ * read(3, 0x94fbc08, 1024) = -1 EBADF (Bad file descriptor)
+ * ^^^^^^^^ oops, wrong fd!!!
+ * With this case separate from sqp == NULL and *after* move_HFILEs,
+ * it now works:
+ */
+ if (sqp == ERR_PTR) {
+ /* Don't preserve redirected fds: exec is _meant_ to change these */
+ //bb_error_msg("sqp == ERR_PTR: exec >FILE");
+ return 0;
+ }
+
+ /* Check whether it collides with any open fds (e.g. stdio), save fds as needed */
+ *sqp = add_squirrel(*sqp, fd, avoid_fd);
+ return 0; /* "we did not close fd" */
+}
+
+static void restore_redirects(struct squirrel *sq)
+{
+ if (sq) {
+ int i;
+ for (i = 0; sq[i].orig_fd >= 0; i++) {
+ if (sq[i].moved_to >= 0) {
+ /* We simply die on error */
+ debug_printf_redir("restoring redirected fd from %d to %d\n", sq[i].moved_to, sq[i].orig_fd);
+ xmove_fd(sq[i].moved_to, sq[i].orig_fd);
+ } else {
+ /* cmd1 9>FILE; cmd2_should_see_fd9_closed */
+ debug_printf_redir("restoring redirected fd %d: closing it\n", sq[i].orig_fd);
+ close(sq[i].orig_fd);
+ }
+ }
+ free(sq);
+ }
+ if (G.HFILE_stdin
+ && G.HFILE_stdin->fd > STDIN_FILENO
+ /* we compare > STDIN, not == STDIN, since hfgetc()
+ * closes fd and sets ->fd to -1 if EOF is reached.
+ * Testcase: echo 'pwd' | hush
+ */
+ ) {
+ /* Testcase: interactive "read r <FILE; echo $r; read r; echo $r".
+ * Redirect moves ->fd to e.g. 10,
+ * and it is not restored above (we do not restore script fds
+ * after redirects, we just use new, "moved" fds).
+ * However for stdin, get_user_input() -> read_line_input(),
+ * and read builtin, depend on fd == STDIN_FILENO.
+ */
+ debug_printf_redir("restoring %d to stdin\n", G.HFILE_stdin->fd);
+ xmove_fd(G.HFILE_stdin->fd, STDIN_FILENO);
+ G.HFILE_stdin->fd = STDIN_FILENO;
+ }
+
+ /* If moved, G_interactive_fd stays on new fd, not restoring it */
+}
+
+#if ENABLE_FEATURE_SH_STANDALONE && BB_MMU
+static void close_saved_fds_and_FILE_fds(void)
+{
+ if (G_interactive_fd)
+ close(G_interactive_fd);
+ close_all_HFILE_list();
+}
+#endif
+
+static int internally_opened_fd(int fd, struct squirrel *sq)
+{
+ int i;
+
+#if ENABLE_HUSH_INTERACTIVE
+ if (fd == G_interactive_fd)
+ return 1;
+#endif
+ /* If this one of script's fds? */
+ if (fd_in_HFILEs(fd))
+ return 1;
+
+ if (sq) for (i = 0; sq[i].orig_fd >= 0; i++) {
+ if (fd == sq[i].moved_to)
+ return 1;
+ }
+ return 0;
+}
+
+/* squirrel != NULL means we squirrel away copies of stdin, stdout,
+ * and stderr if they are redirected. */
+static int setup_redirects(struct command *prog, struct squirrel **sqp)
+{
+ struct redir_struct *redir;
+
+ for (redir = prog->redirects; redir; redir = redir->next) {
+ int newfd;
+ int closed;
+
+ if (redir->rd_type == REDIRECT_HEREDOC2) {
+ /* "rd_fd<<HERE" case */
+ save_fd_on_redirect(redir->rd_fd, /*avoid:*/ 0, sqp);
+ /* for REDIRECT_HEREDOC2, rd_filename holds _contents_
+ * of the heredoc */
+ debug_printf_redir("set heredoc '%s'\n",
+ redir->rd_filename);
+ setup_heredoc(redir);
+ continue;
+ }
+
+ if (redir->rd_dup == REDIRFD_TO_FILE) {
+ /* "rd_fd<*>file" case (<*> is <,>,>>,<>) */
+ char *p;
+ int mode;
+
+ if (redir->rd_filename == NULL) {
+ /* Examples:
+ * "cmd >" (no filename)
+ * "cmd > <file" (2nd redirect starts too early)
+ */
+ syntax_error("invalid redirect");
+ continue;
+ }
+ mode = redir_table[redir->rd_type].mode;
+ p = expand_string_to_string(redir->rd_filename,
+ EXP_FLAG_ESC_GLOB_CHARS, /*unbackslash:*/ 1);
+ newfd = open_or_warn(p, mode);
+ free(p);
+ if (newfd < 0) {
+ /* Error message from open_or_warn can be lost
+ * if stderr has been redirected, but bash
+ * and ash both lose it as well
+ * (though zsh doesn't!)
+ */
+ return 1;
+ }
+ if (newfd == redir->rd_fd && sqp) {
+ /* open() gave us precisely the fd we wanted.
+ * This means that this fd was not busy
+ * (not opened to anywhere).
+ * Remember to close it on restore:
+ */
+ *sqp = add_squirrel_closed(*sqp, newfd);
+ debug_printf_redir("redir to previously closed fd %d\n", newfd);
+ }
+ } else {
+ /* "rd_fd>&rd_dup" or "rd_fd>&-" case */
+ newfd = redir->rd_dup;
+ }
+
+ if (newfd == redir->rd_fd)
+ continue;
+
+ /* if "N>FILE": move newfd to redir->rd_fd */
+ /* if "N>&M": dup newfd to redir->rd_fd */
+ /* if "N>&-": close redir->rd_fd (newfd is REDIRFD_CLOSE) */
+
+ closed = save_fd_on_redirect(redir->rd_fd, /*avoid:*/ newfd, sqp);
+ if (newfd == REDIRFD_CLOSE) {
+ /* "N>&-" means "close me" */
+ if (!closed) {
+ /* ^^^ optimization: saving may already
+ * have closed it. If not... */
+ close(redir->rd_fd);
+ }
+ /* Sometimes we do another close on restore, getting EBADF.
+ * Consider "echo 3>FILE 3>&-"
+ * first redirect remembers "need to close 3",
+ * and second redirect closes 3! Restore code then closes 3 again.
+ */
+ } else {
+ /* if newfd is a script fd or saved fd, simulate EBADF */
+ if (internally_opened_fd(newfd, sqp && sqp != ERR_PTR ? *sqp : NULL)) {
+ //errno = EBADF;
+ //bb_perror_msg_and_die("can't duplicate file descriptor");
+ newfd = -1; /* same effect as code above */
+ }
+ xdup2(newfd, redir->rd_fd);
+ if (redir->rd_dup == REDIRFD_TO_FILE)
+ /* "rd_fd > FILE" */
+ close(newfd);
+ /* else: "rd_fd > rd_dup" */
+ }
+ }
+ return 0;
+}
+
+static char *find_in_path(const char *arg)
+{
+ char *ret = NULL;
+ const char *PATH = get_local_var_value("PATH");
+
+ if (!PATH)
+ return NULL;
+
+ while (1) {
+ const char *end = strchrnul(PATH, ':');
+ int sz = end - PATH; /* must be int! */
+
+ free(ret);
+ if (sz != 0) {
+ ret = xasprintf("%.*s/%s", sz, PATH, arg);
+ } else {
+ /* We have xxx::yyyy in $PATH,
+ * it means "use current dir" */
+ ret = xstrdup(arg);
+ }
+ if (access(ret, F_OK) == 0)
+ break;
+
+ if (*end == '\0') {
+ free(ret);
+ return NULL;
+ }
+ PATH = end + 1;
+ }
+
+ return ret;
+}
+
+static const struct built_in_command *find_builtin_helper(const char *name,
+ const struct built_in_command *x,
+ const struct built_in_command *end)
+{
+ while (x != end) {
+ if (strcmp(name, x->b_cmd) != 0) {
+ x++;
+ continue;
+ }
+ debug_printf_exec("found builtin '%s'\n", name);
+ return x;
+ }
+ return NULL;
+}
+static const struct built_in_command *find_builtin1(const char *name)
+{
+ return find_builtin_helper(name, bltins1, &bltins1[ARRAY_SIZE(bltins1)]);
+}
+static const struct built_in_command *find_builtin(const char *name)
+{
+ const struct built_in_command *x = find_builtin1(name);
+ if (x)
+ return x;
+ return find_builtin_helper(name, bltins2, &bltins2[ARRAY_SIZE(bltins2)]);
+}
+
+#if ENABLE_HUSH_JOB && EDITING_HAS_get_exe_name
+static const char * FAST_FUNC get_builtin_name(int i)
+{
+ if (/*i >= 0 && */ i < ARRAY_SIZE(bltins1)) {
+ return bltins1[i].b_cmd;
+ }
+ i -= ARRAY_SIZE(bltins1);
+ if (i < ARRAY_SIZE(bltins2)) {
+ return bltins2[i].b_cmd;
+ }
+ return NULL;
+}
+#endif
+
+static void remove_nested_vars(void)
+{
+ struct variable *cur;
+ struct variable **cur_pp;
+
+ cur_pp = &G.top_var;
+ while ((cur = *cur_pp) != NULL) {
+ if (cur->var_nest_level <= G.var_nest_level) {
+ cur_pp = &cur->next;
+ continue;
+ }
+ /* Unexport */
+ if (cur->flg_export) {
+ debug_printf_env("unexporting nested '%s'/%u\n", cur->varstr, cur->var_nest_level);
+ bb_unsetenv(cur->varstr);
+ }
+ /* Remove from global list */
+ *cur_pp = cur->next;
+ /* Free */
+ if (!cur->max_len) {
+ debug_printf_env("freeing nested '%s'/%u\n", cur->varstr, cur->var_nest_level);
+ free(cur->varstr);
+ }
+ free(cur);
+ }
+}
+
+static void enter_var_nest_level(void)
+{
+ G.var_nest_level++;
+ debug_printf_env("var_nest_level++ %u\n", G.var_nest_level);
+
+ /* Try: f() { echo -n .; f; }; f
+ * struct variable::var_nest_level is uint16_t,
+ * thus limiting recursion to < 2^16.
+ * In any case, with 8 Mbyte stack SEGV happens
+ * not too long after 2^16 recursions anyway.
+ */
+ if (G.var_nest_level > 0xff00)
+ bb_error_msg_and_die("fatal recursion (depth %u)", G.var_nest_level);
+}
+
+static void leave_var_nest_level(void)
+{
+ G.var_nest_level--;
+ debug_printf_env("var_nest_level-- %u\n", G.var_nest_level);
+ if (HUSH_DEBUG && (int)G.var_nest_level < 0)
+ bb_simple_error_msg_and_die("BUG: nesting underflow");
+
+ remove_nested_vars();
+}
+
+#if ENABLE_HUSH_FUNCTIONS
+static struct function **find_function_slot(const char *name)
+{
+ struct function *funcp;
+ struct function **funcpp = &G.top_func;
+
+ while ((funcp = *funcpp) != NULL) {
+ if (strcmp(name, funcp->name) == 0) {
+ debug_printf_exec("found function '%s'\n", name);
+ break;
+ }
+ funcpp = &funcp->next;
+ }
+ return funcpp;
+}
+
+static ALWAYS_INLINE const struct function *find_function(const char *name)
+{
+ const struct function *funcp = *find_function_slot(name);
+ return funcp;
+}
+
+/* Note: takes ownership on name ptr */
+static struct function *new_function(char *name)
+{
+ struct function **funcpp = find_function_slot(name);
+ struct function *funcp = *funcpp;
+
+ if (funcp != NULL) {
+ struct command *cmd = funcp->parent_cmd;
+ debug_printf_exec("func %p parent_cmd %p\n", funcp, cmd);
+ if (!cmd) {
+ debug_printf_exec("freeing & replacing function '%s'\n", funcp->name);
+ free(funcp->name);
+ /* Note: if !funcp->body, do not free body_as_string!
+ * This is a special case of "-F name body" function:
+ * body_as_string was not malloced! */
+ if (funcp->body) {
+ free_pipe_list(funcp->body);
+# if !BB_MMU
+ free(funcp->body_as_string);
+# endif
+ }
+ } else {
+ debug_printf_exec("reinserting in tree & replacing function '%s'\n", funcp->name);
+ cmd->argv[0] = funcp->name;
+ cmd->group = funcp->body;
+# if !BB_MMU
+ cmd->group_as_string = funcp->body_as_string;
+# endif
+ }
+ } else {
+ debug_printf_exec("remembering new function '%s'\n", name);
+ funcp = *funcpp = xzalloc(sizeof(*funcp));
+ /*funcp->next = NULL;*/
+ }
+
+ funcp->name = name;
+ return funcp;
+}
+
+# if ENABLE_HUSH_UNSET
+static void unset_func(const char *name)
+{
+ struct function **funcpp = find_function_slot(name);
+ struct function *funcp = *funcpp;
+
+ if (funcp != NULL) {
+ debug_printf_exec("freeing function '%s'\n", funcp->name);
+ *funcpp = funcp->next;
+ /* funcp is unlinked now, deleting it.
+ * Note: if !funcp->body, the function was created by
+ * "-F name body", do not free ->body_as_string
+ * and ->name as they were not malloced. */
+ if (funcp->body) {
+ free_pipe_list(funcp->body);
+ free(funcp->name);
+# if !BB_MMU
+ free(funcp->body_as_string);
+# endif
+ }
+ free(funcp);
+ }
+}
+# endif
+
+# if BB_MMU
+#define exec_function(to_free, funcp, argv) \
+ exec_function(funcp, argv)
+# endif
+static void exec_function(char ***to_free,
+ const struct function *funcp,
+ char **argv) NORETURN;
+static void exec_function(char ***to_free,
+ const struct function *funcp,
+ char **argv)
+{
+# if BB_MMU
+ int n;
+
+ argv[0] = G.global_argv[0];
+ G.global_argv = argv;
+ G.global_argc = n = 1 + string_array_len(argv + 1);
+
+// Example when we are here: "cmd | func"
+// func will run with saved-redirect fds open.
+// $ f() { echo /proc/self/fd/*; }
+// $ true | f
+// /proc/self/fd/0 /proc/self/fd/1 /proc/self/fd/2 /proc/self/fd/255 /proc/self/fd/3
+// stdio^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ G_interactive_fd^ DIR fd for glob
+// Same in script:
+// $ . ./SCRIPT
+// /proc/self/fd/0 /proc/self/fd/1 /proc/self/fd/2 /proc/self/fd/255 /proc/self/fd/3 /proc/self/fd/4
+// stdio^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ G_interactive_fd^ opened ./SCRIPT DIR fd for glob
+// They are CLOEXEC so external programs won't see them, but
+// for "more correctness" we might want to close those extra fds here:
+//? close_saved_fds_and_FILE_fds();
+
+ /* "we are in a function, ok to use return" */
+ G_flag_return_in_progress = -1;
+ enter_var_nest_level();
+ IF_HUSH_LOCAL(G.func_nest_level++;)
+
+ /* On MMU, funcp->body is always non-NULL */
+ n = run_list(funcp->body);
+ _exit(n);
+# else
+//? close_saved_fds_and_FILE_fds();
+
+//TODO: check whether "true | func_with_return" works
+
+ re_execute_shell(to_free,
+ funcp->body_as_string,
+ G.global_argv[0],
+ argv + 1,
+ NULL);
+# endif
+}
+
+static int run_function(const struct function *funcp, char **argv)
+{
+ int rc;
+ save_arg_t sv;
+ smallint sv_flg;
+
+ save_and_replace_G_args(&sv, argv);
+
+ /* "We are in function, ok to use return" */
+ sv_flg = G_flag_return_in_progress;
+ G_flag_return_in_progress = -1;
+
+ /* Make "local" variables properly shadow previous ones */
+ IF_HUSH_LOCAL(enter_var_nest_level();)
+ IF_HUSH_LOCAL(G.func_nest_level++;)
+
+ /* On MMU, funcp->body is always non-NULL */
+# if !BB_MMU
+ if (!funcp->body) {
+ /* Function defined by -F */
+ parse_and_run_string(funcp->body_as_string);
+ rc = G.last_exitcode;
+ } else
+# endif
+ {
+ rc = run_list(funcp->body);
+ }
+
+ IF_HUSH_LOCAL(G.func_nest_level--;)
+ IF_HUSH_LOCAL(leave_var_nest_level();)
+
+ G_flag_return_in_progress = sv_flg;
+# if ENABLE_HUSH_TRAP
+ debug_printf_exec("G.return_exitcode=-1\n");
+ G.return_exitcode = -1; /* invalidate stashed return value */
+# endif
+
+ restore_G_args(&sv, argv);
+
+ return rc;
+}
+#endif /* ENABLE_HUSH_FUNCTIONS */
+
+
+#if BB_MMU
+#define exec_builtin(to_free, x, argv) \
+ exec_builtin(x, argv)
+#else
+#define exec_builtin(to_free, x, argv) \
+ exec_builtin(to_free, argv)
+#endif
+static void exec_builtin(char ***to_free,
+ const struct built_in_command *x,
+ char **argv) NORETURN;
+static void exec_builtin(char ***to_free,
+ const struct built_in_command *x,
+ char **argv)
+{
+#if BB_MMU
+ int rcode;
+//? close_saved_fds_and_FILE_fds();
+ rcode = x->b_function(argv);
+ fflush_all();
+ _exit(rcode);
+#else
+ fflush_all();
+ /* On NOMMU, we must never block!
+ * Example: { sleep 99 | read line; } & echo Ok
+ */
+ re_execute_shell(to_free,
+ argv[0],
+ G.global_argv[0],
+ G.global_argv + 1,
+ argv);
+#endif
+}
+
+
+static void execvp_or_die(char **argv) NORETURN;
+static void execvp_or_die(char **argv)
+{
+ int e;
+ debug_printf_exec("execing '%s'\n", argv[0]);
+ /* Don't propagate SIG_IGN to the child */
+ if (SPECIAL_JOBSTOP_SIGS != 0)
+ switch_off_special_sigs(G.special_sig_mask & SPECIAL_JOBSTOP_SIGS);
+ execvp(argv[0], argv);
+ e = 2;
+ if (errno == EACCES) e = 126;
+ if (errno == ENOENT) e = 127;
+ bb_perror_msg("can't execute '%s'", argv[0]);
+ _exit(e);
+}
+
+#if ENABLE_HUSH_MODE_X
+static void x_mode_print_optionally_squoted(const char *str)
+{
+ unsigned len;
+ const char *cp;
+
+ cp = str;
+
+ /* the set of chars which-cause-string-to-be-squoted mimics bash */
+ /* test a char with: bash -c 'set -x; echo "CH"' */
+ if (str[strcspn(str, "\\\"'`$(){}[]<>;#&|~*?!^"
+ " " "\001\002\003\004\005\006\007"
+ "\010\011\012\013\014\015\016\017"
+ "\020\021\022\023\024\025\026\027"
+ "\030\031\032\033\034\035\036\037"
+ )
+ ] == '\0'
+ ) {
+ /* string has no special chars */
+ x_mode_addstr(str);
+ return;
+ }
+
+ cp = str;
+ for (;;) {
+ /* print '....' up to EOL or first squote */
+ len = (int)(strchrnul(cp, '\'') - cp);
+ if (len != 0) {
+ x_mode_addchr('\'');
+ x_mode_addblock(cp, len);
+ x_mode_addchr('\'');
+ cp += len;
+ }
+ if (*cp == '\0')
+ break;
+ /* string contains squote(s), print them as \' */
+ x_mode_addchr('\\');
+ x_mode_addchr('\'');
+ cp++;
+ }
+}
+static void dump_cmd_in_x_mode(char **argv)
+{
+ if (G_x_mode && argv) {
+ unsigned n;
+
+ /* "+[+++...][ cmd...]\n\0" */
+ x_mode_prefix();
+ n = 0;
+ while (argv[n]) {
+ x_mode_addchr(' ');
+ if (argv[n][0] == '\0') {
+ x_mode_addchr('\'');
+ x_mode_addchr('\'');
+ } else {
+ x_mode_print_optionally_squoted(argv[n]);
+ }
+ n++;
+ }
+ x_mode_flush();
+ }
+}
+#else
+# define dump_cmd_in_x_mode(argv) ((void)0)
+#endif
+
+#if ENABLE_HUSH_COMMAND
+static void if_command_vV_print_and_exit(char opt_vV, char *cmd, const char *explanation)
+{
+ char *to_free;
+
+ if (!opt_vV)
+ return;
+
+ to_free = NULL;
+ if (!explanation) {
+ char *path = getenv("PATH");
+ explanation = to_free = find_executable(cmd, &path); /* path == NULL is ok */
+ if (!explanation)
+ _exit(1); /* PROG was not found */
+ if (opt_vV != 'V')
+ cmd = to_free; /* -v PROG prints "/path/to/PROG" */
+ }
+ printf((opt_vV == 'V') ? "%s is %s\n" : "%s\n", cmd, explanation);
+ free(to_free);
+ fflush_all();
+ _exit(0);
+}
+#else
+# define if_command_vV_print_and_exit(a,b,c) ((void)0)
+#endif
+
+#if BB_MMU
+#define pseudo_exec_argv(nommu_save, argv, assignment_cnt, argv_expanded) \
+ pseudo_exec_argv(argv, assignment_cnt, argv_expanded)
+#define pseudo_exec(nommu_save, command, argv_expanded) \
+ pseudo_exec(command, argv_expanded)
+#endif
+
+/* Called after [v]fork() in run_pipe, or from builtin_exec.
+ * Never returns.
+ * Don't exit() here. If you don't exec, use _exit instead.
+ * The at_exit handlers apparently confuse the calling process,
+ * in particular stdin handling. Not sure why? -- because of vfork! (vda)
+ */
+static void pseudo_exec_argv(nommu_save_t *nommu_save,
+ char **argv, int assignment_cnt,
+ char **argv_expanded) NORETURN;
+static NOINLINE void pseudo_exec_argv(nommu_save_t *nommu_save,
+ char **argv, int assignment_cnt,
+ char **argv_expanded)
+{
+ const struct built_in_command *x;
+ struct variable **sv_shadowed;
+ char **new_env;
+ IF_HUSH_COMMAND(char opt_vV = 0;)
+ IF_HUSH_FUNCTIONS(const struct function *funcp;)
+
+ new_env = expand_assignments(argv, assignment_cnt);
+ dump_cmd_in_x_mode(new_env);
+
+ if (!argv[assignment_cnt]) {
+ /* Case when we are here: ... | var=val | ...
+ * (note that we do not exit early, i.e., do not optimize out
+ * expand_assignments(): think about ... | var=`sleep 1` | ...
+ */
+ free_strings(new_env);
+ _exit(EXIT_SUCCESS);
+ }
+
+ sv_shadowed = G.shadowed_vars_pp;
+#if BB_MMU
+ G.shadowed_vars_pp = NULL; /* "don't save, free them instead" */
+#else
+ G.shadowed_vars_pp = &nommu_save->old_vars;
+ G.var_nest_level++;
+#endif
+ set_vars_and_save_old(new_env);
+ G.shadowed_vars_pp = sv_shadowed;
+
+ if (argv_expanded) {
+ argv = argv_expanded;
+ } else {
+ argv = expand_strvec_to_strvec(argv + assignment_cnt);
+#if !BB_MMU
+ nommu_save->argv = argv;
+#endif
+ }
+ dump_cmd_in_x_mode(argv);
+
+#if ENABLE_FEATURE_SH_STANDALONE || BB_MMU
+ if (strchr(argv[0], '/') != NULL)
+ goto skip;
+#endif
+
+#if ENABLE_HUSH_FUNCTIONS
+ /* Check if the command matches any functions (this goes before bltins) */
+ funcp = find_function(argv[0]);
+ if (funcp)
+ exec_function(&nommu_save->argv_from_re_execing, funcp, argv);
+#endif
+
+#if ENABLE_HUSH_COMMAND
+ /* "command BAR": run BAR without looking it up among functions
+ * "command -v BAR": print "BAR" or "/path/to/BAR"; or exit 1
+ * "command -V BAR": print "BAR is {a function,a shell builtin,/path/to/BAR}"
+ */
+ while (strcmp(argv[0], "command") == 0 && argv[1]) {
+ char *p;
+
+ argv++;
+ p = *argv;
+ if (p[0] != '-' || !p[1])
+ continue; /* bash allows "command command command [-OPT] BAR" */
+
+ for (;;) {
+ p++;
+ switch (*p) {
+ case '\0':
+ argv++;
+ p = *argv;
+ if (p[0] != '-' || !p[1])
+ goto after_opts;
+ continue; /* next arg is also -opts, process it too */
+ case 'v':
+ case 'V':
+ opt_vV = *p;
+ continue;
+ default:
+ bb_error_msg_and_die("%s: %s: invalid option", "command", argv[0]);
+ }
+ }
+ }
+ after_opts:
+# if ENABLE_HUSH_FUNCTIONS
+ if (opt_vV && find_function(argv[0]))
+ if_command_vV_print_and_exit(opt_vV, argv[0], "a function");
+# endif
+#endif
+
+ /* Check if the command matches any of the builtins.
+ * Depending on context, this might be redundant. But it's
+ * easier to waste a few CPU cycles than it is to figure out
+ * if this is one of those cases.
+ */
+ /* Why "BB_MMU ? :" difference in logic? -
+ * On NOMMU, it is more expensive to re-execute shell
+ * just in order to run echo or test builtin.
+ * It's better to skip it here and run corresponding
+ * non-builtin later. */
+ x = BB_MMU ? find_builtin(argv[0]) : find_builtin1(argv[0]);
+ if (x) {
+ if_command_vV_print_and_exit(opt_vV, argv[0], "a shell builtin");
+ exec_builtin(&nommu_save->argv_from_re_execing, x, argv);
+ }
+
+#if ENABLE_FEATURE_SH_STANDALONE
+ /* Check if the command matches any busybox applets */
+ {
+ int a = find_applet_by_name(argv[0]);
+ if (a >= 0) {
+ if_command_vV_print_and_exit(opt_vV, argv[0], "an applet");
+# if BB_MMU /* see above why on NOMMU it is not allowed */
+ if (APPLET_IS_NOEXEC(a)) {
+ /* Do not leak open fds from opened script files etc.
+ * Testcase: interactive "ls -l /proc/self/fd"
+ * should not show tty fd open.
+ */
+ close_saved_fds_and_FILE_fds();
+//FIXME: should also close saved redir fds
+//This casuses test failures in
+//redir_children_should_not_see_saved_fd_2.tests
+//redir_children_should_not_see_saved_fd_3.tests
+//if you replace "busybox find" with just "find" in them
+ /* Without this, "rm -i FILE" can't be ^C'ed: */
+ switch_off_special_sigs(G.special_sig_mask);
+ debug_printf_exec("running applet '%s'\n", argv[0]);
+ run_noexec_applet_and_exit(a, argv[0], argv);
+ }
+# endif
+ /* Re-exec ourselves */
+ debug_printf_exec("re-execing applet '%s'\n", argv[0]);
+ /* Don't propagate SIG_IGN to the child */
+ if (SPECIAL_JOBSTOP_SIGS != 0)
+ switch_off_special_sigs(G.special_sig_mask & SPECIAL_JOBSTOP_SIGS);
+ execv(bb_busybox_exec_path, argv);
+ /* If they called chroot or otherwise made the binary no longer
+ * executable, fall through */
+ }
+ }
+#endif
+
+#if ENABLE_FEATURE_SH_STANDALONE || BB_MMU
+ skip:
+#endif
+ if_command_vV_print_and_exit(opt_vV, argv[0], NULL);
+ execvp_or_die(argv);
+}
+
+/* Called after [v]fork() in run_pipe
+ */
+static void pseudo_exec(nommu_save_t *nommu_save,
+ struct command *command,
+ char **argv_expanded) NORETURN;
+static void pseudo_exec(nommu_save_t *nommu_save,
+ struct command *command,
+ char **argv_expanded)
+{
+#if ENABLE_HUSH_FUNCTIONS
+ if (command->cmd_type == CMD_FUNCDEF) {
+ /* Ignore funcdefs in pipes:
+ * true | f() { cmd }
+ */
+ _exit(0);
+ }
+#endif
+
+ if (command->argv) {
+ pseudo_exec_argv(nommu_save, command->argv,
+ command->assignment_cnt, argv_expanded);
+ }
+
+ if (command->group) {
+ /* Cases when we are here:
+ * ( list )
+ * { list } &
+ * ... | ( list ) | ...
+ * ... | { list } | ...
+ */
+#if BB_MMU
+ int rcode;
+ debug_printf_exec("pseudo_exec: run_list\n");
+ reset_traps_to_defaults();
+ rcode = run_list(command->group);
+ /* OK to leak memory by not calling free_pipe_list,
+ * since this process is about to exit */
+ _exit(rcode);
+#else
+ re_execute_shell(&nommu_save->argv_from_re_execing,
+ command->group_as_string,
+ G.global_argv[0],
+ G.global_argv + 1,
+ NULL);
+#endif
+ }
+
+ /* Case when we are here: ... | >file */
+ debug_printf_exec("pseudo_exec'ed null command\n");
+ _exit(EXIT_SUCCESS);
+}
+
+#if ENABLE_HUSH_JOB
+static const char *get_cmdtext(struct pipe *pi)
+{
+ char **argv;
+ char *p;
+ int len;
+
+ /* This is subtle. ->cmdtext is created only on first backgrounding.
+ * (Think "cat, <ctrl-z>, fg, <ctrl-z>, fg, <ctrl-z>...." here...)
+ * On subsequent bg argv is trashed, but we won't use it */
+ if (pi->cmdtext)
+ return pi->cmdtext;
+
+ argv = pi->cmds[0].argv;
+ if (!argv) {
+ pi->cmdtext = xzalloc(1);
+ return pi->cmdtext;
+ }
+ len = 0;
+ do {
+ len += strlen(*argv) + 1;
+ } while (*++argv);
+ p = xmalloc(len);
+ pi->cmdtext = p;
+ argv = pi->cmds[0].argv;
+ do {
+ p = stpcpy(p, *argv);
+ *p++ = ' ';
+ } while (*++argv);
+ p[-1] = '\0';
+ return pi->cmdtext;
+}
+
+static void remove_job_from_table(struct pipe *pi)
+{
+ struct pipe *prev_pipe;
+
+ if (pi == G.job_list) {
+ G.job_list = pi->next;
+ } else {
+ prev_pipe = G.job_list;
+ while (prev_pipe->next != pi)
+ prev_pipe = prev_pipe->next;
+ prev_pipe->next = pi->next;
+ }
+ G.last_jobid = 0;
+ if (G.job_list)
+ G.last_jobid = G.job_list->jobid;
+}
+
+static void delete_finished_job(struct pipe *pi)
+{
+ remove_job_from_table(pi);
+ free_pipe(pi);
+}
+
+static void clean_up_last_dead_job(void)
+{
+ if (G.job_list && !G.job_list->alive_cmds)
+ delete_finished_job(G.job_list);
+}
+
+static void insert_job_into_table(struct pipe *pi)
+{
+ struct pipe *job, **jobp;
+ int i;
+
+ clean_up_last_dead_job();
+
+ /* Find the end of the list, and find next job ID to use */
+ i = 0;
+ jobp = &G.job_list;
+ while ((job = *jobp) != NULL) {
+ if (job->jobid > i)
+ i = job->jobid;
+ jobp = &job->next;
+ }
+ pi->jobid = i + 1;
+
+ /* Create a new job struct at the end */
+ job = *jobp = xmemdup(pi, sizeof(*pi));
+ job->next = NULL;
+ job->cmds = xzalloc(sizeof(pi->cmds[0]) * pi->num_cmds);
+ /* Cannot copy entire pi->cmds[] vector! This causes double frees */
+ for (i = 0; i < pi->num_cmds; i++) {
+ job->cmds[i].pid = pi->cmds[i].pid;
+ /* all other fields are not used and stay zero */
+ }
+ job->cmdtext = xstrdup(get_cmdtext(pi));
+
+ if (G_interactive_fd)
+ printf("[%u] %u %s\n", job->jobid, (unsigned)job->cmds[0].pid, job->cmdtext);
+ G.last_jobid = job->jobid;
+}
+#endif /* JOB */
+
+static int job_exited_or_stopped(struct pipe *pi)
+{
+ int rcode, i;
+
+ if (pi->alive_cmds != pi->stopped_cmds)
+ return -1;
+
+ /* All processes in fg pipe have exited or stopped */
+ rcode = 0;
+ i = pi->num_cmds;
+ while (--i >= 0) {
+ rcode = pi->cmds[i].cmd_exitcode;
+ /* usually last process gives overall exitstatus,
+ * but with "set -o pipefail", last *failed* process does */
+ if (G.o_opt[OPT_O_PIPEFAIL] == 0 || rcode != 0)
+ break;
+ }
+ IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;)
+ return rcode;
+}
+
+static int process_wait_result(struct pipe *fg_pipe, pid_t childpid, int status)
+{
+#if ENABLE_HUSH_JOB
+ struct pipe *pi;
+#endif
+ int i, dead;
+
+ dead = WIFEXITED(status) || WIFSIGNALED(status);
+
+#if DEBUG_JOBS
+ if (WIFSTOPPED(status))
+ debug_printf_jobs("pid %d stopped by sig %d (exitcode %d)\n",
+ childpid, WSTOPSIG(status), WEXITSTATUS(status));
+ if (WIFSIGNALED(status))
+ debug_printf_jobs("pid %d killed by sig %d (exitcode %d)\n",
+ childpid, WTERMSIG(status), WEXITSTATUS(status));
+ if (WIFEXITED(status))
+ debug_printf_jobs("pid %d exited, exitcode %d\n",
+ childpid, WEXITSTATUS(status));
+#endif
+ /* Were we asked to wait for a fg pipe? */
+ if (fg_pipe) {
+ i = fg_pipe->num_cmds;
+
+ while (--i >= 0) {
+ int rcode;
+
+ debug_printf_jobs("check pid %d\n", fg_pipe->cmds[i].pid);
+ if (fg_pipe->cmds[i].pid != childpid)
+ continue;
+ if (dead) {
+ int ex;
+ fg_pipe->cmds[i].pid = 0;
+ fg_pipe->alive_cmds--;
+ ex = WEXITSTATUS(status);
+ /* bash prints killer signal's name for *last*
+ * process in pipe (prints just newline for SIGINT/SIGPIPE).
+ * Mimic this. Example: "sleep 5" + (^\ or kill -QUIT)
+ */
+ if (WIFSIGNALED(status)) {
+ int sig = WTERMSIG(status);
+#if ENABLE_HUSH_JOB
+ if (G.run_list_level == 1
+ /* ^^^^^ Do not print in nested contexts, example:
+ * echo `sleep 1; sh -c 'kill -9 $$'` - prints "137", NOT "Killed 137"
+ */
+ && i == fg_pipe->num_cmds-1
+ ) {
+ /* strsignal() is for bash compat. ~600 bloat versus bbox's get_signame() */
+ puts(sig == SIGINT || sig == SIGPIPE ? "" : strsignal(sig));
+ }
+#endif
+ /* TODO: if (WCOREDUMP(status)) + " (core dumped)"; */
+ /* MIPS has 128 sigs (1..128), if sig==128,
+ * 128 + sig would result in exitcode 256 -> 0!
+ */
+ ex = 128 | sig;
+ }
+ fg_pipe->cmds[i].cmd_exitcode = ex;
+ } else {
+ fg_pipe->stopped_cmds++;
+ }
+ debug_printf_jobs("fg_pipe: alive_cmds %d stopped_cmds %d\n",
+ fg_pipe->alive_cmds, fg_pipe->stopped_cmds);
+ rcode = job_exited_or_stopped(fg_pipe);
+ if (rcode >= 0) {
+/* Note: *non-interactive* bash does not continue if all processes in fg pipe
+ * are stopped. Testcase: "cat | cat" in a script (not on command line!)
+ * and "killall -STOP cat" */
+ if (G_interactive_fd) {
+#if ENABLE_HUSH_JOB
+ if (fg_pipe->alive_cmds != 0)
+ insert_job_into_table(fg_pipe);
+#endif
+ return rcode;
+ }
+ if (fg_pipe->alive_cmds == 0)
+ return rcode;
+ }
+ /* There are still running processes in the fg_pipe */
+ return -1;
+ }
+ /* It wasn't in fg_pipe, look for process in bg pipes */
+ }
+
+#if ENABLE_HUSH_JOB
+ /* We were asked to wait for bg or orphaned children */
+ /* No need to remember exitcode in this case */
+ for (pi = G.job_list; pi; pi = pi->next) {
+ for (i = 0; i < pi->num_cmds; i++) {
+ if (pi->cmds[i].pid == childpid)
+ goto found_pi_and_prognum;
+ }
+ }
+ /* Happens when shell is used as init process (init=/bin/sh) */
+ debug_printf("checkjobs: pid %d was not in our list!\n", childpid);
+ return -1; /* this wasn't a process from fg_pipe */
+
+ found_pi_and_prognum:
+ if (dead) {
+ /* child exited */
+ int rcode = WEXITSTATUS(status);
+ if (WIFSIGNALED(status))
+ /* NB: not 128 + sig, MIPS has sig 128 */
+ rcode = 128 | WTERMSIG(status);
+ pi->cmds[i].cmd_exitcode = rcode;
+ if (G.last_bg_pid == pi->cmds[i].pid)
+ G.last_bg_pid_exitcode = rcode;
+ pi->cmds[i].pid = 0;
+ pi->alive_cmds--;
+ if (!pi->alive_cmds) {
+# if ENABLE_HUSH_BASH_COMPAT
+ G.dead_job_exitcode = job_exited_or_stopped(pi);
+# endif
+ if (G_interactive_fd) {
+ printf(JOB_STATUS_FORMAT, pi->jobid,
+ "Done", pi->cmdtext);
+ delete_finished_job(pi);
+ } else {
+/*
+ * bash deletes finished jobs from job table only in interactive mode,
+ * after "jobs" cmd, or if pid of a new process matches one of the old ones
+ * (see cleanup_dead_jobs(), delete_old_job(), J_NOTIFIED in bash source).
+ * Testcase script: "(exit 3) & sleep 1; wait %1; echo $?" prints 3 in bash.
+ * We only retain one "dead" job, if it's the single job on the list.
+ * This covers most of real-world scenarios where this is useful.
+ */
+ if (pi != G.job_list)
+ delete_finished_job(pi);
+ }
+ }
+ } else {
+ /* child stopped */
+ pi->stopped_cmds++;
+ }
+#endif
+ return -1; /* this wasn't a process from fg_pipe */
+}
+
+/* Check to see if any processes have exited -- if they have,
+ * figure out why and see if a job has completed.
+ *
+ * If non-NULL fg_pipe: wait for its completion or stop.
+ * Return its exitcode or zero if stopped.
+ *
+ * Alternatively (fg_pipe == NULL, waitfor_pid != 0):
+ * waitpid(WNOHANG), if waitfor_pid exits or stops, return exitcode+1,
+ * else return <0 if waitpid errors out (e.g. ECHILD: nothing to wait for)
+ * or 0 if no children changed status.
+ *
+ * Alternatively (fg_pipe == NULL, waitfor_pid == 0),
+ * return <0 if waitpid errors out (e.g. ECHILD: nothing to wait for)
+ * or 0 if no children changed status.
+ */
+static int checkjobs(struct pipe *fg_pipe, pid_t waitfor_pid)
+{
+ int attributes;
+ int status;
+ int rcode = 0;
+
+ debug_printf_jobs("checkjobs %p\n", fg_pipe);
+
+ attributes = WUNTRACED;
+ if (fg_pipe == NULL)
+ attributes |= WNOHANG;
+
+ errno = 0;
+#if ENABLE_HUSH_FAST
+ if (G.handled_SIGCHLD == G.count_SIGCHLD) {
+//bb_error_msg("[%d] checkjobs: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d children?:%d fg_pipe:%p",
+//getpid(), G.count_SIGCHLD, G.handled_SIGCHLD, G.we_have_children, fg_pipe);
+ /* There was neither fork nor SIGCHLD since last waitpid */
+ /* Avoid doing waitpid syscall if possible */
+ if (!G.we_have_children) {
+ errno = ECHILD;
+ return -1;
+ }
+ if (fg_pipe == NULL) { /* is WNOHANG set? */
+ /* We have children, but they did not exit
+ * or stop yet (we saw no SIGCHLD) */
+ return 0;
+ }
+ /* else: !WNOHANG, waitpid will block, can't short-circuit */
+ }
+#endif
+
+/* Do we do this right?
+ * bash-3.00# sleep 20 | false
+ * <ctrl-Z pressed>
+ * [3]+ Stopped sleep 20 | false
+ * bash-3.00# echo $?
+ * 1 <========== bg pipe is not fully done, but exitcode is already known!
+ * [hush 1.14.0: yes we do it right]
+ */
+ while (1) {
+ pid_t childpid;
+#if ENABLE_HUSH_FAST
+ int i;
+ i = G.count_SIGCHLD;
+#endif
+ childpid = waitpid(-1, &status, attributes);
+ if (childpid <= 0) {
+ if (childpid && errno != ECHILD)
+ bb_simple_perror_msg("waitpid");
+#if ENABLE_HUSH_FAST
+ else { /* Until next SIGCHLD, waitpid's are useless */
+ G.we_have_children = (childpid == 0);
+ G.handled_SIGCHLD = i;
+//bb_error_msg("[%d] checkjobs: waitpid returned <= 0, G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
+ }
+#endif
+ /* ECHILD (no children), or 0 (no change in children status) */
+ rcode = childpid;
+ break;
+ }
+ rcode = process_wait_result(fg_pipe, childpid, status);
+ if (rcode >= 0) {
+ /* fg_pipe exited or stopped */
+ break;
+ }
+ if (childpid == waitfor_pid) { /* "wait PID" */
+ debug_printf_exec("childpid==waitfor_pid:%d status:0x%08x\n", childpid, status);
+ rcode = WEXITSTATUS(status);
+ if (WIFSIGNALED(status))
+ rcode = 128 | WTERMSIG(status);
+ if (WIFSTOPPED(status))
+ /* bash: "cmd & wait $!" and cmd stops: $? = 128 | stopsig */
+ rcode = 128 | WSTOPSIG(status);
+ rcode++;
+ break; /* "wait PID" called us, give it exitcode+1 */
+ }
+#if ENABLE_HUSH_BASH_COMPAT
+ if (-1 == waitfor_pid /* "wait -n" (wait for any one job) */
+ && G.dead_job_exitcode >= 0 /* some job did finish */
+ ) {
+ debug_printf_exec("waitfor_pid:-1\n");
+ rcode = G.dead_job_exitcode + 1;
+ break;
+ }
+#endif
+ /* This wasn't one of our processes, or */
+ /* fg_pipe still has running processes, do waitpid again */
+ } /* while (waitpid succeeds)... */
+
+ return rcode;
+}
+
+#if ENABLE_HUSH_JOB
+static int checkjobs_and_fg_shell(struct pipe *fg_pipe)
+{
+ pid_t p;
+ int rcode = checkjobs(fg_pipe, 0 /*(no pid to wait for)*/);
+ if (G_saved_tty_pgrp) {
+ /* Job finished, move the shell to the foreground */
+ p = getpgrp(); /* our process group id */
+ debug_printf_jobs("fg'ing ourself: getpgrp()=%d\n", (int)p);
+ tcsetpgrp(G_interactive_fd, p);
+ }
+ return rcode;
+}
+#endif
+
+/* Start all the jobs, but don't wait for anything to finish.
+ * See checkjobs().
+ *
+ * Return code is normally -1, when the caller has to wait for children
+ * to finish to determine the exit status of the pipe. If the pipe
+ * is a simple builtin command, however, the action is done by the
+ * time run_pipe returns, and the exit code is provided as the
+ * return value.
+ *
+ * Returns -1 only if started some children. IOW: we have to
+ * mask out retvals of builtins etc with 0xff!
+ *
+ * The only case when we do not need to [v]fork is when the pipe
+ * is single, non-backgrounded, non-subshell command. Examples:
+ * cmd ; ... { list } ; ...
+ * cmd && ... { list } && ...
+ * cmd || ... { list } || ...
+ * If it is, then we can run cmd as a builtin, NOFORK,
+ * or (if SH_STANDALONE) an applet, and we can run the { list }
+ * with run_list. If it isn't one of these, we fork and exec cmd.
+ *
+ * Cases when we must fork:
+ * non-single: cmd | cmd
+ * backgrounded: cmd & { list } &
+ * subshell: ( list ) [&]
+ */
+#if !ENABLE_HUSH_MODE_X
+#define redirect_and_varexp_helper(command, sqp, argv_expanded) \
+ redirect_and_varexp_helper(command, sqp)
+#endif
+static int redirect_and_varexp_helper(
+ struct command *command,
+ struct squirrel **sqp,
+ char **argv_expanded)
+{
+ /* Assignments occur before redirects. Try:
+ * a=`sleep 1` sleep 2 3>/qwe/rty
+ */
+
+ char **new_env = expand_assignments(command->argv, command->assignment_cnt);
+ dump_cmd_in_x_mode(new_env);
+ dump_cmd_in_x_mode(argv_expanded);
+ /* this takes ownership of new_env[i] elements, and frees new_env: */
+ set_vars_and_save_old(new_env);
+
+ return setup_redirects(command, sqp);
+}
+static NOINLINE int run_pipe(struct pipe *pi)
+{
+ static const char *const null_ptr = NULL;
+
+ int cmd_no;
+ int next_infd;
+ struct command *command;
+ char **argv_expanded;
+ char **argv;
+ struct squirrel *squirrel = NULL;
+ int rcode;
+
+ debug_printf_exec("run_pipe start: members:%d\n", pi->num_cmds);
+ debug_enter();
+
+ /* Testcase: set -- q w e; (IFS='' echo "$*"; IFS=''; echo "$*"); echo "$*"
+ * Result should be 3 lines: q w e, qwe, q w e
+ */
+ if (G.ifs_whitespace != G.ifs)
+ free(G.ifs_whitespace);
+ G.ifs = get_local_var_value("IFS");
+ if (G.ifs) {
+ char *p;
+ G.ifs_whitespace = (char*)G.ifs;
+ p = skip_whitespace(G.ifs);
+ if (*p) {
+ /* Not all $IFS is whitespace */
+ char *d;
+ int len = p - G.ifs;
+ p = skip_non_whitespace(p);
+ G.ifs_whitespace = xmalloc(len + strlen(p) + 1); /* can overestimate */
+ d = mempcpy(G.ifs_whitespace, G.ifs, len);
+ while (*p) {
+ if (isspace(*p))
+ *d++ = *p;
+ p++;
+ }
+ *d = '\0';
+ }
+ } else {
+ G.ifs = defifs;
+ G.ifs_whitespace = (char*)G.ifs;
+ }
+
+ IF_HUSH_JOB(pi->pgrp = -1;)
+ pi->stopped_cmds = 0;
+ command = &pi->cmds[0];
+ argv_expanded = NULL;
+
+ if (pi->num_cmds != 1
+ || pi->followup == PIPE_BG
+ || command->cmd_type == CMD_SUBSHELL
+ ) {
+ goto must_fork;
+ }
+
+ pi->alive_cmds = 1;
+
+ debug_printf_exec(": group:%p argv:'%s'\n",
+ command->group, command->argv ? command->argv[0] : "NONE");
+
+ if (command->group) {
+#if ENABLE_HUSH_FUNCTIONS
+ if (command->cmd_type == CMD_FUNCDEF) {
+ /* "executing" func () { list } */
+ struct function *funcp;
+
+ funcp = new_function(command->argv[0]);
+ /* funcp->name is already set to argv[0] */
+ funcp->body = command->group;
+# if !BB_MMU
+ funcp->body_as_string = command->group_as_string;
+ command->group_as_string = NULL;
+# endif
+ command->group = NULL;
+ command->argv[0] = NULL;
+ debug_printf_exec("cmd %p has child func at %p\n", command, funcp);
+ funcp->parent_cmd = command;
+ command->child_func = funcp;
+
+ debug_printf_exec("run_pipe: return EXIT_SUCCESS\n");
+ debug_leave();
+ return EXIT_SUCCESS;
+ }
+#endif
+ /* { list } */
+ debug_printf_exec("non-subshell group\n");
+ rcode = 1; /* exitcode if redir failed */
+ if (setup_redirects(command, &squirrel) == 0) {
+ debug_printf_exec(": run_list\n");
+//FIXME: we need to pass squirrel down into run_list()
+//for SH_STANDALONE case, or else this construct:
+// { find /proc/self/fd; true; } >FILE; cmd2
+//has no way of closing saved fd#1 for "find",
+//and in SH_STANDALONE mode, "find" is not execed,
+//therefore CLOEXEC on saved fd does not help.
+ rcode = run_list(command->group) & 0xff;
+ }
+ restore_redirects(squirrel);
+ IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;)
+ debug_leave();
+ debug_printf_exec("run_pipe: return %d\n", rcode);
+ return rcode;
+ }
+
+ argv = command->argv ? command->argv : (char **) &null_ptr;
+ {
+ const struct built_in_command *x;
+ IF_HUSH_FUNCTIONS(const struct function *funcp;)
+ IF_NOT_HUSH_FUNCTIONS(enum { funcp = 0 };)
+ struct variable **sv_shadowed;
+ struct variable *old_vars;
+
+#if ENABLE_HUSH_LINENO_VAR
+ G.execute_lineno = command->lineno;
+#endif
+
+ if (argv[command->assignment_cnt] == NULL) {
+ /* Assignments, but no command.
+ * Ensure redirects take effect (that is, create files).
+ * Try "a=t >file"
+ */
+ unsigned i;
+ G.expand_exitcode = 0;
+ only_assignments:
+ rcode = setup_redirects(command, &squirrel);
+ restore_redirects(squirrel);
+
+ /* Set shell variables */
+ i = 0;
+ while (i < command->assignment_cnt) {
+ char *p = expand_string_to_string(argv[i],
+ EXP_FLAG_ESC_GLOB_CHARS,
+ /*unbackslash:*/ 1
+ );
+#if ENABLE_HUSH_MODE_X
+ if (G_x_mode) {
+ char *eq;
+ if (i == 0)
+ x_mode_prefix();
+ x_mode_addchr(' ');
+ eq = strchrnul(p, '=');
+ if (*eq) eq++;
+ x_mode_addblock(p, (eq - p));
+ x_mode_print_optionally_squoted(eq);
+ x_mode_flush();
+ }
+#endif
+ debug_printf_env("set shell var:'%s'->'%s'\n", *argv, p);
+ if (set_local_var(p, /*flag:*/ 0)) {
+ /* assignment to readonly var / putenv error? */
+ rcode = 1;
+ }
+ i++;
+ }
+ /* Redirect error sets $? to 1. Otherwise,
+ * if evaluating assignment value set $?, retain it.
+ * Else, clear $?:
+ * false; q=`exit 2`; echo $? - should print 2
+ * false; x=1; echo $? - should print 0
+ * Because of the 2nd case, we can't just use G.last_exitcode.
+ */
+ if (rcode == 0)
+ rcode = G.expand_exitcode;
+ IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;)
+ debug_leave();
+ debug_printf_exec("run_pipe: return %d\n", rcode);
+ return rcode;
+ }
+
+ /* Expand the rest into (possibly) many strings each */
+#if defined(CMD_TEST2_SINGLEWORD_NOGLOB)
+ if (command->cmd_type == CMD_TEST2_SINGLEWORD_NOGLOB)
+ argv_expanded = expand_strvec_to_strvec_singleword_noglob(argv + command->assignment_cnt);
+ else
+#endif
+#if defined(CMD_SINGLEWORD_NOGLOB)
+ if (command->cmd_type == CMD_SINGLEWORD_NOGLOB)
+ argv_expanded = expand_strvec_to_strvec_singleword_noglob(argv + command->assignment_cnt);
+ else
+#endif
+ argv_expanded = expand_strvec_to_strvec(argv + command->assignment_cnt);
+
+ /* If someone gives us an empty string: `cmd with empty output` */
+ if (!argv_expanded[0]) {
+ free(argv_expanded);
+ /* `false` still has to set exitcode 1 */
+ G.expand_exitcode = G.last_exitcode;
+ goto only_assignments;
+ }
+
+ old_vars = NULL;
+ sv_shadowed = G.shadowed_vars_pp;
+
+ /* Check if argv[0] matches any functions (this goes before bltins) */
+ IF_HUSH_FUNCTIONS(funcp = find_function(argv_expanded[0]);)
+ IF_HUSH_FUNCTIONS(x = NULL;)
+ IF_HUSH_FUNCTIONS(if (!funcp))
+ x = find_builtin(argv_expanded[0]);
+ if (x || funcp) {
+ if (x && x->b_function == builtin_exec && argv_expanded[1] == NULL) {
+ debug_printf("exec with redirects only\n");
+ /*
+ * Variable assignments are executed, but then "forgotten":
+ * a=`sleep 1;echo A` exec 3>&-; echo $a
+ * sleeps, but prints nothing.
+ */
+ enter_var_nest_level();
+ G.shadowed_vars_pp = &old_vars;
+ rcode = redirect_and_varexp_helper(command,
+ /*squirrel:*/ ERR_PTR,
+ argv_expanded
+ );
+ G.shadowed_vars_pp = sv_shadowed;
+ /* rcode=1 can be if redir file can't be opened */
+
+ goto clean_up_and_ret1;
+ }
+
+ /* Bump var nesting, or this will leak exported $a:
+ * a=b true; env | grep ^a=
+ */
+ enter_var_nest_level();
+ /* Collect all variables "shadowed" by helper
+ * (IOW: old vars overridden by "var1=val1 var2=val2 cmd..." syntax)
+ * into old_vars list:
+ */
+ G.shadowed_vars_pp = &old_vars;
+ rcode = redirect_and_varexp_helper(command, &squirrel, argv_expanded);
+ if (rcode == 0) {
+ if (!funcp) {
+ /* Do not collect *to old_vars list* vars shadowed
+ * by e.g. "local VAR" builtin (collect them
+ * in the previously nested list instead):
+ * don't want them to be restored immediately
+ * after "local" completes.
+ */
+ G.shadowed_vars_pp = sv_shadowed;
+
+ debug_printf_exec(": builtin '%s' '%s'...\n",
+ x->b_cmd, argv_expanded[1]);
+ fflush_all();
+ rcode = x->b_function(argv_expanded) & 0xff;
+ fflush_all();
+ }
+#if ENABLE_HUSH_FUNCTIONS
+ else {
+ debug_printf_exec(": function '%s' '%s'...\n",
+ funcp->name, argv_expanded[1]);
+ rcode = run_function(funcp, argv_expanded) & 0xff;
+ /*
+ * But do collect *to old_vars list* vars shadowed
+ * within function execution. To that end, restore
+ * this pointer _after_ function run:
+ */
+ G.shadowed_vars_pp = sv_shadowed;
+ }
+#endif
+ }
+ } else
+ if (ENABLE_FEATURE_SH_NOFORK && NUM_APPLETS > 1) {
+ int n = find_applet_by_name(argv_expanded[0]);
+ if (n < 0 || !APPLET_IS_NOFORK(n))
+ goto must_fork;
+
+ enter_var_nest_level();
+ /* Collect all variables "shadowed" by helper into old_vars list */
+ G.shadowed_vars_pp = &old_vars;
+ rcode = redirect_and_varexp_helper(command, &squirrel, argv_expanded);
+ G.shadowed_vars_pp = sv_shadowed;
+
+ if (rcode == 0) {
+ debug_printf_exec(": run_nofork_applet '%s' '%s'...\n",
+ argv_expanded[0], argv_expanded[1]);
+ /*
+ * Note: signals (^C) can't interrupt here.
+ * We remember them and they will be acted upon
+ * after applet returns.
+ * This makes applets which can run for a long time
+ * and/or wait for user input ineligible for NOFORK:
+ * for example, "yes" or "rm" (rm -i waits for input).
+ */
+ rcode = run_nofork_applet(n, argv_expanded);
+ }
+ } else
+ goto must_fork;
+
+ restore_redirects(squirrel);
+ clean_up_and_ret1:
+ leave_var_nest_level();
+ add_vars(old_vars);
+
+ /*
+ * Try "usleep 99999999" + ^C + "echo $?"
+ * with FEATURE_SH_NOFORK=y.
+ */
+ if (!funcp) {
+ /* It was builtin or nofork.
+ * if this would be a real fork/execed program,
+ * it should have died if a fatal sig was received.
+ * But OTOH, there was no separate process,
+ * the sig was sent to _shell_, not to non-existing
+ * child.
+ * Let's just handle ^C only, this one is obvious:
+ * we aren't ok with exitcode 0 when ^C was pressed
+ * during builtin/nofork.
+ */
+ if (sigismember(&G.pending_set, SIGINT))
+ rcode = 128 | SIGINT;
+ }
+ free(argv_expanded);
+ IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;)
+ debug_leave();
+ debug_printf_exec("run_pipe return %d\n", rcode);
+ return rcode;
+ }
+
+ must_fork:
+ /* NB: argv_expanded may already be created, and that
+ * might include `cmd` runs! Do not rerun it! We *must*
+ * use argv_expanded if it's non-NULL */
+
+ /* Going to fork a child per each pipe member */
+ pi->alive_cmds = 0;
+ next_infd = 0;
+
+ cmd_no = 0;
+ while (cmd_no < pi->num_cmds) {
+ struct fd_pair pipefds;
+#if !BB_MMU
+ int sv_var_nest_level = G.var_nest_level;
+ volatile nommu_save_t nommu_save;
+ nommu_save.old_vars = NULL;
+ nommu_save.argv = NULL;
+ nommu_save.argv_from_re_execing = NULL;
+#endif
+ command = &pi->cmds[cmd_no];
+ cmd_no++;
+ if (command->argv) {
+ debug_printf_exec(": pipe member '%s' '%s'...\n",
+ command->argv[0], command->argv[1]);
+ } else {
+ debug_printf_exec(": pipe member with no argv\n");
+ }
+
+ /* pipes are inserted between pairs of commands */
+ pipefds.rd = 0;
+ pipefds.wr = 1;
+ if (cmd_no < pi->num_cmds)
+ xpiped_pair(pipefds);
+
+#if ENABLE_HUSH_LINENO_VAR
+ G.execute_lineno = command->lineno;
+#endif
+
+ command->pid = BB_MMU ? fork() : vfork();
+ if (!command->pid) { /* child */
+#if ENABLE_HUSH_JOB
+ disable_restore_tty_pgrp_on_exit();
+ CLEAR_RANDOM_T(&G.random_gen); /* or else $RANDOM repeats in child */
+
+ /* Every child adds itself to new process group
+ * with pgid == pid_of_first_child_in_pipe */
+ if (G.run_list_level == 1 && G_interactive_fd) {
+ pid_t pgrp;
+ pgrp = pi->pgrp;
+ if (pgrp < 0) /* true for 1st process only */
+ pgrp = getpid();
+ if (setpgid(0, pgrp) == 0
+ && pi->followup != PIPE_BG
+ && G_saved_tty_pgrp /* we have ctty */
+ ) {
+ /* We do it in *every* child, not just first,
+ * to avoid races */
+ tcsetpgrp(G_interactive_fd, pgrp);
+ }
+ }
+#endif
+ if (pi->alive_cmds == 0 && pi->followup == PIPE_BG) {
+ /* 1st cmd in backgrounded pipe
+ * should have its stdin /dev/null'ed */
+ close(0);
+ if (open(bb_dev_null, O_RDONLY))
+ xopen("/", O_RDONLY);
+ } else {
+ xmove_fd(next_infd, 0);
+ }
+ xmove_fd(pipefds.wr, 1);
+ if (pipefds.rd > 1)
+ close(pipefds.rd);
+ /* Like bash, explicit redirects override pipes,
+ * and the pipe fd (fd#1) is available for dup'ing:
+ * "cmd1 2>&1 | cmd2": fd#1 is duped to fd#2, thus stderr
+ * of cmd1 goes into pipe.
+ */
+ if (setup_redirects(command, NULL)) {
+ /* Happens when redir file can't be opened:
+ * $ hush -c 'echo FOO >&2 | echo BAR 3>/qwe/rty; echo BAZ'
+ * FOO
+ * hush: can't open '/qwe/rty': No such file or directory
+ * BAZ
+ * (echo BAR is not executed, it hits _exit(1) below)
+ */
+ _exit(1);
+ }
+
+ /* Stores to nommu_save list of env vars putenv'ed
+ * (NOMMU, on MMU we don't need that) */
+ /* cast away volatility... */
+ pseudo_exec((nommu_save_t*) &nommu_save, command, argv_expanded);
+ /* pseudo_exec() does not return */
+ }
+
+ /* parent or error */
+#if ENABLE_HUSH_FAST
+ G.count_SIGCHLD++;
+//bb_error_msg("[%d] fork in run_pipe: G.count_SIGCHLD:%d G.handled_SIGCHLD:%d", getpid(), G.count_SIGCHLD, G.handled_SIGCHLD);
+#endif
+ enable_restore_tty_pgrp_on_exit();
+#if !BB_MMU
+ /* Clean up after vforked child */
+ free(nommu_save.argv);
+ free(nommu_save.argv_from_re_execing);
+ G.var_nest_level = sv_var_nest_level;
+ remove_nested_vars();
+ add_vars(nommu_save.old_vars);
+#endif
+ free(argv_expanded);
+ argv_expanded = NULL;
+ if (command->pid < 0) { /* [v]fork failed */
+ /* Clearly indicate, was it fork or vfork */
+ bb_simple_perror_msg(BB_MMU ? "vfork"+1 : "vfork");
+ } else {
+ pi->alive_cmds++;
+#if ENABLE_HUSH_JOB
+ /* Second and next children need to know pid of first one */
+ if (pi->pgrp < 0)
+ pi->pgrp = command->pid;
+#endif
+ }
+
+ if (cmd_no > 1)
+ close(next_infd);
+ if (cmd_no < pi->num_cmds)
+ close(pipefds.wr);
+ /* Pass read (output) pipe end to next iteration */
+ next_infd = pipefds.rd;
+ }
+
+ if (!pi->alive_cmds) {
+ debug_leave();
+ debug_printf_exec("run_pipe return 1 (all forks failed, no children)\n");
+ return 1;
+ }
+
+ debug_leave();
+ debug_printf_exec("run_pipe return -1 (%u children started)\n", pi->alive_cmds);
+ return -1;
+}
+
+/* NB: called by pseudo_exec, and therefore must not modify any
+ * global data until exec/_exit (we can be a child after vfork!) */
+static int run_list(struct pipe *pi)
+{
+#if ENABLE_HUSH_CASE
+ char *case_word = NULL;
+#endif
+#if ENABLE_HUSH_LOOPS
+ struct pipe *loop_top = NULL;
+ char **for_lcur = NULL;
+ char **for_list = NULL;
+#endif
+ smallint last_followup;
+ smalluint rcode;
+#if ENABLE_HUSH_IF || ENABLE_HUSH_CASE
+ smalluint cond_code = 0;
+#else
+ enum { cond_code = 0 };
+#endif
+#if HAS_KEYWORDS
+ smallint rword; /* RES_foo */
+ smallint last_rword; /* ditto */
+#endif
+
+ debug_printf_exec("run_list start lvl %d\n", G.run_list_level);
+ debug_enter();
+
+#if ENABLE_HUSH_LOOPS
+ /* Check syntax for "for" */
+ {
+ struct pipe *cpipe;
+ for (cpipe = pi; cpipe; cpipe = cpipe->next) {
+ if (cpipe->res_word != RES_FOR && cpipe->res_word != RES_IN)
+ continue;
+ /* current word is FOR or IN (BOLD in comments below) */
+ if (cpipe->next == NULL) {
+ syntax_error("malformed for");
+ debug_leave();
+ debug_printf_exec("run_list lvl %d return 1\n", G.run_list_level);
+ return 1;
+ }
+ /* "FOR v; do ..." and "for v IN a b; do..." are ok */
+ if (cpipe->next->res_word == RES_DO)
+ continue;
+ /* next word is not "do". It must be "in" then ("FOR v in ...") */
+ if (cpipe->res_word == RES_IN /* "for v IN a b; not_do..."? */
+ || cpipe->next->res_word != RES_IN /* FOR v not_do_and_not_in..."? */
+ ) {
+ syntax_error("malformed for");
+ debug_leave();
+ debug_printf_exec("run_list lvl %d return 1\n", G.run_list_level);
+ return 1;
+ }
+ }
+ }
+#endif
+
+ /* Past this point, all code paths should jump to ret: label
+ * in order to return, no direct "return" statements please.
+ * This helps to ensure that no memory is leaked. */
+
+#if ENABLE_HUSH_JOB
+ G.run_list_level++;
+#endif
+
+#if HAS_KEYWORDS
+ rword = RES_NONE;
+ last_rword = RES_XXXX;
+#endif
+ last_followup = PIPE_SEQ;
+ rcode = G.last_exitcode;
+
+ /* Go through list of pipes, (maybe) executing them. */
+ for (; pi; pi = IF_HUSH_LOOPS(rword == RES_DONE ? loop_top : ) pi->next) {
+ int r;
+ int sv_errexit_depth;
+
+ if (G.flag_SIGINT)
+ break;
+ if (G_flag_return_in_progress == 1)
+ break;
+
+ IF_HAS_KEYWORDS(rword = pi->res_word;)
+ debug_printf_exec(": rword=%d cond_code=%d last_rword=%d\n",
+ rword, cond_code, last_rword);
+
+ sv_errexit_depth = G.errexit_depth;
+ if (
+#if ENABLE_HUSH_IF
+ rword == RES_IF || rword == RES_ELIF ||
+#endif
+ pi->followup != PIPE_SEQ
+ ) {
+ G.errexit_depth++;
+ }
+#if ENABLE_HUSH_LOOPS
+ if ((rword == RES_WHILE || rword == RES_UNTIL || rword == RES_FOR)
+ && loop_top == NULL /* avoid bumping G.depth_of_loop twice */
+ ) {
+ /* start of a loop: remember where loop starts */
+ loop_top = pi;
+ G.depth_of_loop++;
+ }
+#endif
+ /* Still in the same "if...", "then..." or "do..." branch? */
+ if (IF_HAS_KEYWORDS(rword == last_rword &&) 1) {
+ if ((rcode == 0 && last_followup == PIPE_OR)
+ || (rcode != 0 && last_followup == PIPE_AND)
+ ) {
+ /* It is "<true> || CMD" or "<false> && CMD"
+ * and we should not execute CMD */
+ debug_printf_exec("skipped cmd because of || or &&\n");
+ last_followup = pi->followup;
+ goto dont_check_jobs_but_continue;
+ }
+ }
+ last_followup = pi->followup;
+ IF_HAS_KEYWORDS(last_rword = rword;)
+#if ENABLE_HUSH_IF
+ if (cond_code) {
+ if (rword == RES_THEN) {
+ /* if false; then ... fi has exitcode 0! */
+ G.last_exitcode = rcode = EXIT_SUCCESS;
+ /* "if <false> THEN cmd": skip cmd */
+ continue;
+ }
+ } else {
+ if (rword == RES_ELSE || rword == RES_ELIF) {
+ /* "if <true> then ... ELSE/ELIF cmd":
+ * skip cmd and all following ones */
+ break;
+ }
+ }
+#endif
+#if ENABLE_HUSH_LOOPS
+ if (rword == RES_FOR) { /* && pi->num_cmds - always == 1 */
+ if (!for_lcur) {
+ /* first loop through for */
+
+ static const char encoded_dollar_at[] ALIGN1 = {
+ SPECIAL_VAR_SYMBOL, '@' | 0x80, SPECIAL_VAR_SYMBOL, '\0'
+ }; /* encoded representation of "$@" */
+ static const char *const encoded_dollar_at_argv[] = {
+ encoded_dollar_at, NULL
+ }; /* argv list with one element: "$@" */
+ char **vals;
+
+ G.last_exitcode = rcode = EXIT_SUCCESS;
+ vals = (char**)encoded_dollar_at_argv;
+ if (pi->next->res_word == RES_IN) {
+ /* if no variable values after "in" we skip "for" */
+ if (!pi->next->cmds[0].argv) {
+ debug_printf_exec(": null FOR: exitcode EXIT_SUCCESS\n");
+ break;
+ }
+ vals = pi->next->cmds[0].argv;
+ } /* else: "for var; do..." -> assume "$@" list */
+ /* create list of variable values */
+ debug_print_strings("for_list made from", vals);
+ for_list = expand_strvec_to_strvec(vals);
+ for_lcur = for_list;
+ debug_print_strings("for_list", for_list);
+ }
+ if (!*for_lcur) {
+ /* "for" loop is over, clean up */
+ free(for_list);
+ for_list = NULL;
+ for_lcur = NULL;
+ break;
+ }
+ /* Insert next value from for_lcur */
+ /* note: *for_lcur already has quotes removed, $var expanded, etc */
+ set_local_var(xasprintf("%s=%s", pi->cmds[0].argv[0], *for_lcur++), /*flag:*/ 0);
+ continue;
+ }
+ if (rword == RES_IN) {
+ continue; /* "for v IN list;..." - "in" has no cmds anyway */
+ }
+ if (rword == RES_DONE) {
+ continue; /* "done" has no cmds too */
+ }
+#endif
+#if ENABLE_HUSH_CASE
+ if (rword == RES_CASE) {
+ debug_printf_exec("CASE cond_code:%d\n", cond_code);
+ case_word = expand_string_to_string(pi->cmds->argv[0],
+ EXP_FLAG_ESC_GLOB_CHARS, /*unbackslash:*/ 1);
+ debug_printf_exec("CASE word1:'%s'\n", case_word);
+ //unbackslash(case_word);
+ //debug_printf_exec("CASE word2:'%s'\n", case_word);
+ continue;
+ }
+ if (rword == RES_MATCH) {
+ char **argv;
+
+ debug_printf_exec("MATCH cond_code:%d\n", cond_code);
+ if (!case_word) /* "case ... matched_word) ... WORD)": we executed selected branch, stop */
+ break;
+ /* all prev words didn't match, does this one match? */
+ argv = pi->cmds->argv;
+ while (*argv) {
+ char *pattern;
+ debug_printf_exec("expand_string_to_string('%s')\n", *argv);
+ pattern = expand_string_to_string(*argv,
+ EXP_FLAG_ESC_GLOB_CHARS,
+ /*unbackslash:*/ 0
+ );
+ /* TODO: which FNM_xxx flags to use? */
+ cond_code = (fnmatch(pattern, case_word, /*flags:*/ 0) != 0);
+ debug_printf_exec("fnmatch(pattern:'%s',str:'%s'):%d\n",
+ pattern, case_word, cond_code);
+ free(pattern);
+ if (cond_code == 0) {
+ /* match! we will execute this branch */
+ free(case_word);
+ case_word = NULL; /* make future "word)" stop */
+ break;
+ }
+ argv++;
+ }
+ continue;
+ }
+ if (rword == RES_CASE_BODY) { /* inside of a case branch */
+ debug_printf_exec("CASE_BODY cond_code:%d\n", cond_code);
+ if (cond_code != 0)
+ continue; /* not matched yet, skip this pipe */
+ }
+ if (rword == RES_ESAC) {
+ debug_printf_exec("ESAC cond_code:%d\n", cond_code);
+ if (case_word) {
+ /* "case" did not match anything: still set $? (to 0) */
+ G.last_exitcode = rcode = EXIT_SUCCESS;
+ }
+ }
+#endif
+ /* Just pressing <enter> in shell should check for jobs.
+ * OTOH, in non-interactive shell this is useless
+ * and only leads to extra job checks */
+ if (pi->num_cmds == 0) {
+ if (G_interactive_fd)
+ goto check_jobs_and_continue;
+ continue;
+ }
+
+ /* After analyzing all keywords and conditions, we decided
+ * to execute this pipe. NB: have to do checkjobs(NULL)
+ * after run_pipe to collect any background children,
+ * even if list execution is to be stopped. */
+ debug_printf_exec(": run_pipe with %d members\n", pi->num_cmds);
+#if ENABLE_HUSH_LOOPS
+ G.flag_break_continue = 0;
+#endif
+ rcode = r = run_pipe(pi); /* NB: rcode is a smalluint, r is int */
+ if (r != -1) {
+ /* We ran a builtin, function, or group.
+ * rcode is already known
+ * and we don't need to wait for anything. */
+ debug_printf_exec(": builtin/func exitcode %d\n", rcode);
+ G.last_exitcode = rcode;
+ check_and_run_traps();
+#if ENABLE_HUSH_TRAP && ENABLE_HUSH_FUNCTIONS
+ rcode = G.last_exitcode; /* "return" in trap can change it, read back */
+#endif
+#if ENABLE_HUSH_LOOPS
+ /* Was it "break" or "continue"? */
+ if (G.flag_break_continue) {
+ smallint fbc = G.flag_break_continue;
+ /* We might fall into outer *loop*,
+ * don't want to break it too */
+ if (loop_top) {
+ G.depth_break_continue--;
+ if (G.depth_break_continue == 0)
+ G.flag_break_continue = 0;
+ /* else: e.g. "continue 2" should *break* once, *then* continue */
+ } /* else: "while... do... { we are here (innermost list is not a loop!) };...done" */
+ if (G.depth_break_continue != 0 || fbc == BC_BREAK) {
+ checkjobs(NULL, 0 /*(no pid to wait for)*/);
+ break;
+ }
+ /* "continue": simulate end of loop */
+ rword = RES_DONE;
+ continue;
+ }
+#endif
+ if (G_flag_return_in_progress == 1) {
+ checkjobs(NULL, 0 /*(no pid to wait for)*/);
+ break;
+ }
+ } else if (pi->followup == PIPE_BG) {
+ /* What does bash do with attempts to background builtins? */
+ /* even bash 3.2 doesn't do that well with nested bg:
+ * try "{ { sleep 10; echo DEEP; } & echo HERE; } &".
+ * I'm NOT treating inner &'s as jobs */
+#if ENABLE_HUSH_JOB
+ if (G.run_list_level == 1)
+ insert_job_into_table(pi);
+#endif
+ /* Last command's pid goes to $! */
+ G.last_bg_pid = pi->cmds[pi->num_cmds - 1].pid;
+ G.last_bg_pid_exitcode = 0;
+ debug_printf_exec(": cmd&: exitcode EXIT_SUCCESS\n");
+/* Check pi->pi_inverted? "! sleep 1 & echo $?": bash says 1. dash and ash say 0 */
+ rcode = EXIT_SUCCESS;
+ goto check_traps;
+ } else {
+#if ENABLE_HUSH_JOB
+ if (G.run_list_level == 1 && G_interactive_fd) {
+ /* Waits for completion, then fg's main shell */
+ rcode = checkjobs_and_fg_shell(pi);
+ debug_printf_exec(": checkjobs_and_fg_shell exitcode %d\n", rcode);
+ goto check_traps;
+ }
+#endif
+ /* This one just waits for completion */
+ rcode = checkjobs(pi, 0 /*(no pid to wait for)*/);
+ debug_printf_exec(": checkjobs exitcode %d\n", rcode);
+ check_traps:
+ G.last_exitcode = rcode;
+ check_and_run_traps();
+#if ENABLE_HUSH_TRAP && ENABLE_HUSH_FUNCTIONS
+ rcode = G.last_exitcode; /* "return" in trap can change it, read back */
+#endif
+ }
+
+ /* Handle "set -e" */
+ if (rcode != 0 && G.o_opt[OPT_O_ERREXIT]) {
+ debug_printf_exec("ERREXIT:1 errexit_depth:%d\n", G.errexit_depth);
+ if (G.errexit_depth == 0)
+ hush_exit(rcode);
+ }
+ G.errexit_depth = sv_errexit_depth;
+
+ /* Analyze how result affects subsequent commands */
+#if ENABLE_HUSH_IF
+ if (rword == RES_IF || rword == RES_ELIF)
+ cond_code = rcode;
+#endif
+ check_jobs_and_continue:
+ checkjobs(NULL, 0 /*(no pid to wait for)*/);
+ dont_check_jobs_but_continue: ;
+#if ENABLE_HUSH_LOOPS
+ /* Beware of "while false; true; do ..."! */
+ if (pi->next
+ && (pi->next->res_word == RES_DO || pi->next->res_word == RES_DONE)
+ /* check for RES_DONE is needed for "while ...; do \n done" case */
+ ) {
+ if (rword == RES_WHILE) {
+ if (rcode) {
+ /* "while false; do...done" - exitcode 0 */
+ G.last_exitcode = rcode = EXIT_SUCCESS;
+ debug_printf_exec(": while expr is false: breaking (exitcode:EXIT_SUCCESS)\n");
+ break;
+ }
+ }
+ if (rword == RES_UNTIL) {
+ if (!rcode) {
+ debug_printf_exec(": until expr is true: breaking\n");
+ break;
+ }
+ }
+ }
+#endif
+ } /* for (pi) */
+
+#if ENABLE_HUSH_JOB
+ G.run_list_level--;
+#endif
+#if ENABLE_HUSH_LOOPS
+ if (loop_top)
+ G.depth_of_loop--;
+ free(for_list);
+#endif
+#if ENABLE_HUSH_CASE
+ free(case_word);
+#endif
+ debug_leave();
+ debug_printf_exec("run_list lvl %d return %d\n", G.run_list_level + 1, rcode);
+ return rcode;
+}
+
+/* Select which version we will use */
+static int run_and_free_list(struct pipe *pi)
+{
+ int rcode = 0;
+ debug_printf_exec("run_and_free_list entered\n");
+ if (!G.o_opt[OPT_O_NOEXEC]) {
+ debug_printf_exec(": run_list: 1st pipe with %d cmds\n", pi->num_cmds);
+ rcode = run_list(pi);
+ }
+ /* free_pipe_list has the side effect of clearing memory.
+ * In the long run that function can be merged with run_list,
+ * but doing that now would hobble the debugging effort. */
+ free_pipe_list(pi);
+ debug_printf_exec("run_and_free_list return %d\n", rcode);
+ return rcode;
+}
+
+
+static void install_sighandlers(unsigned mask)
+{
+ sighandler_t old_handler;
+ unsigned sig = 0;
+ while ((mask >>= 1) != 0) {
+ sig++;
+ if (!(mask & 1))
+ continue;
+ old_handler = install_sighandler(sig, pick_sighandler(sig));
+ /* POSIX allows shell to re-enable SIGCHLD
+ * even if it was SIG_IGN on entry.
+ * Therefore we skip IGN check for it:
+ */
+ if (sig == SIGCHLD)
+ continue;
+ /* Interactive bash re-enables SIGHUP which is SIG_IGNed on entry.
+ * Try:
+ * trap '' hup; bash; echo RET # type "kill -hup $$", see SIGHUP having effect
+ * trap '' hup; bash -c 'kill -hup $$; echo ALIVE' # here SIGHUP is SIG_IGNed
+ */
+ if (sig == SIGHUP && G_interactive_fd)
+ continue;
+ /* Unless one of the above signals, is it SIG_IGN? */
+ if (old_handler == SIG_IGN) {
+ /* oops... restore back to IGN, and record this fact */
+ install_sighandler(sig, old_handler);
+#if ENABLE_HUSH_TRAP
+ if (!G_traps)
+ G_traps = xzalloc(sizeof(G_traps[0]) * NSIG);
+ free(G_traps[sig]);
+ G_traps[sig] = xzalloc(1); /* == xstrdup(""); */
+#endif
+ }
+ }
+}
+
+/* Called a few times only (or even once if "sh -c") */
+static void install_special_sighandlers(void)
+{
+ unsigned mask;
+
+ /* Which signals are shell-special? */
+ mask = (1 << SIGQUIT) | (1 << SIGCHLD);
+ if (G_interactive_fd) {
+ mask |= SPECIAL_INTERACTIVE_SIGS;
+ if (G_saved_tty_pgrp) /* we have ctty, job control sigs work */
+ mask |= SPECIAL_JOBSTOP_SIGS;
+ }
+ /* Careful, do not re-install handlers we already installed */
+ if (G.special_sig_mask != mask) {
+ unsigned diff = mask & ~G.special_sig_mask;
+ G.special_sig_mask = mask;
+ install_sighandlers(diff);
+ }
+}
+
+#if ENABLE_HUSH_JOB
+/* helper */
+/* Set handlers to restore tty pgrp and exit */
+static void install_fatal_sighandlers(void)
+{
+ unsigned mask;
+
+ /* We will restore tty pgrp on these signals */
+ mask = 0
+ /*+ (1 << SIGILL ) * HUSH_DEBUG*/
+ /*+ (1 << SIGFPE ) * HUSH_DEBUG*/
+ + (1 << SIGBUS ) * HUSH_DEBUG
+ + (1 << SIGSEGV) * HUSH_DEBUG
+ /*+ (1 << SIGTRAP) * HUSH_DEBUG*/
+ + (1 << SIGABRT)
+ /* bash 3.2 seems to handle these just like 'fatal' ones */
+ + (1 << SIGPIPE)
+ + (1 << SIGALRM)
+ /* if we are interactive, SIGHUP, SIGTERM and SIGINT are special sigs.
+ * if we aren't interactive... but in this case
+ * we never want to restore pgrp on exit, and this fn is not called
+ */
+ /*+ (1 << SIGHUP )*/
+ /*+ (1 << SIGTERM)*/
+ /*+ (1 << SIGINT )*/
+ ;
+ G_fatal_sig_mask = mask;
+
+ install_sighandlers(mask);
+}
+#endif
+
+static int set_mode(int state, char mode, const char *o_opt)
+{
+ int idx;
+ switch (mode) {
+ case 'n':
+ G.o_opt[OPT_O_NOEXEC] = state;
+ break;
+ case 'x':
+ IF_HUSH_MODE_X(G_x_mode = state;)
+ IF_HUSH_MODE_X(if (G.x_mode_fd <= 0) G.x_mode_fd = dup_CLOEXEC(2, 10);)
+ break;
+ case 'e':
+ G.o_opt[OPT_O_ERREXIT] = state;
+ break;
+ case 'o':
+ if (!o_opt) {
+ /* "set -o" or "set +o" without parameter.
+ * in bash, set -o produces this output:
+ * pipefail off
+ * and set +o:
+ * set +o pipefail
+ * We always use the second form.
+ */
+ const char *p = o_opt_strings;
+ idx = 0;
+ while (*p) {
+ printf("set %co %s\n", (G.o_opt[idx] ? '-' : '+'), p);
+ idx++;
+ p += strlen(p) + 1;
+ }
+ break;
+ }
+ idx = index_in_strings(o_opt_strings, o_opt);
+ if (idx >= 0) {
+ G.o_opt[idx] = state;
+ break;
+ }
+ /* fall through to error */
+ default:
+ return EXIT_FAILURE;
+ }
+ return EXIT_SUCCESS;
+}
+
+int hush_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int hush_main(int argc, char **argv)
+{
+ pid_t cached_getpid;
+ enum {
+ OPT_login = (1 << 0),
+ };
+ unsigned flags;
+#if !BB_MMU
+ unsigned builtin_argc = 0;
+#endif
+ char **e;
+ struct variable *cur_var;
+ struct variable *shell_ver;
+
+ INIT_G();
+ if (EXIT_SUCCESS != 0) /* if EXIT_SUCCESS == 0, it is already done */
+ G.last_exitcode = EXIT_SUCCESS;
+#if ENABLE_HUSH_TRAP
+# if ENABLE_HUSH_FUNCTIONS
+ G.return_exitcode = -1;
+# endif
+ G.pre_trap_exitcode = -1;
+#endif
+
+#if ENABLE_HUSH_FAST
+ G.count_SIGCHLD++; /* ensure it is != G.handled_SIGCHLD */
+#endif
+#if !BB_MMU
+ G.argv0_for_re_execing = argv[0];
+#endif
+
+ cached_getpid = getpid(); /* for tcsetpgrp() during init */
+ G.root_pid = cached_getpid; /* for $PID (NOMMU can override via -$HEXPID:HEXPPID:...) */
+ G.root_ppid = getppid(); /* for $PPID (NOMMU can override) */
+
+ /* Deal with HUSH_VERSION */
+ debug_printf_env("unsetenv '%s'\n", "HUSH_VERSION");
+ unsetenv("HUSH_VERSION"); /* in case it exists in initial env */
+ shell_ver = xzalloc(sizeof(*shell_ver));
+ shell_ver->flg_export = 1;
+ shell_ver->flg_read_only = 1;
+ /* Code which handles ${var<op>...} needs writable values for all variables,
+ * therefore we xstrdup: */
+ shell_ver->varstr = xstrdup(hush_version_str);
+
+ /* Create shell local variables from the values
+ * currently living in the environment */
+ G.top_var = shell_ver;
+ cur_var = G.top_var;
+ e = environ;
+ if (e) while (*e) {
+ char *value = strchr(*e, '=');
+ if (value) { /* paranoia */
+ cur_var->next = xzalloc(sizeof(*cur_var));
+ cur_var = cur_var->next;
+ cur_var->varstr = *e;
+ cur_var->max_len = strlen(*e);
+ cur_var->flg_export = 1;
+ }
+ e++;
+ }
+ /* (Re)insert HUSH_VERSION into env (AFTER we scanned the env!) */
+ debug_printf_env("putenv '%s'\n", shell_ver->varstr);
+ putenv(shell_ver->varstr);
+
+ /* Export PWD */
+ set_pwd_var(SETFLAG_EXPORT);
+
+#if BASH_HOSTNAME_VAR
+ /* Set (but not export) HOSTNAME unless already set */
+ if (!get_local_var_value("HOSTNAME")) {
+ struct utsname uts;
+ uname(&uts);
+ set_local_var_from_halves("HOSTNAME", uts.nodename);
+ }
+#endif
+ /* IFS is not inherited from the parent environment */
+ set_local_var_from_halves("IFS", defifs);
+
+ if (!get_local_var_value("PATH"))
+ set_local_var_from_halves("PATH", bb_default_root_path);
+
+ /* PS1/PS2 are set later, if we determine that we are interactive */
+
+ /* bash also exports SHLVL and _,
+ * and sets (but doesn't export) the following variables:
+ * BASH=/bin/bash
+ * BASH_VERSINFO=([0]="3" [1]="2" [2]="0" [3]="1" [4]="release" [5]="i386-pc-linux-gnu")
+ * BASH_VERSION='3.2.0(1)-release'
+ * HOSTTYPE=i386
+ * MACHTYPE=i386-pc-linux-gnu
+ * OSTYPE=linux-gnu
+ * PPID=<NNNNN> - we also do it elsewhere
+ * EUID=<NNNNN>
+ * UID=<NNNNN>
+ * GROUPS=()
+ * LINES=<NNN>
+ * COLUMNS=<NNN>
+ * BASH_ARGC=()
+ * BASH_ARGV=()
+ * BASH_LINENO=()
+ * BASH_SOURCE=()
+ * DIRSTACK=()
+ * PIPESTATUS=([0]="0")
+ * HISTFILE=/<xxx>/.bash_history
+ * HISTFILESIZE=500
+ * HISTSIZE=500
+ * MAILCHECK=60
+ * PATH=/usr/gnu/bin:/usr/local/bin:/bin:/usr/bin:.
+ * SHELL=/bin/bash
+ * SHELLOPTS=braceexpand:emacs:hashall:histexpand:history:interactive-comments:monitor
+ * TERM=dumb
+ * OPTERR=1
+ * OPTIND=1
+ * PS4='+ '
+ */
+
+#if NUM_SCRIPTS > 0
+ if (argc < 0) {
+ char *script = get_script_content(-argc - 1);
+ G.global_argv = argv;
+ G.global_argc = string_array_len(argv);
+ //install_special_sighandlers(); - needed?
+ parse_and_run_string(script);
+ goto final_return;
+ }
+#endif
+
+ /* Initialize some more globals to non-zero values */
+ die_func = restore_ttypgrp_and__exit;
+
+ /* Shell is non-interactive at first. We need to call
+ * install_special_sighandlers() if we are going to execute "sh <script>",
+ * "sh -c <cmds>" or login shell's /etc/profile and friends.
+ * If we later decide that we are interactive, we run install_special_sighandlers()
+ * in order to intercept (more) signals.
+ */
+
+ /* Parse options */
+ /* http://www.opengroup.org/onlinepubs/9699919799/utilities/sh.html */
+ flags = (argv[0] && argv[0][0] == '-') ? OPT_login : 0;
+ while (1) {
+ int opt = getopt(argc, argv, "+" /* stop at 1st non-option */
+ "cexinsl"
+#if !BB_MMU
+ "<:$:R:V:"
+# if ENABLE_HUSH_FUNCTIONS
+ "F:"
+# endif
+#endif
+ );
+ if (opt <= 0)
+ break;
+ switch (opt) {
+ case 'c':
+ /* Note: -c is not an option with param!
+ * "hush -c -l SCRIPT" is valid. "hush -cSCRIPT" is not.
+ */
+ G.opt_c = 1;
+ break;
+ case 'i':
+ /* Well, we cannot just declare interactiveness,
+ * we have to have some stuff (ctty, etc) */
+ /* G_interactive_fd++; */
+ break;
+ case 's':
+ G.opt_s = 1;
+ break;
+ case 'l':
+ flags |= OPT_login;
+ break;
+#if !BB_MMU
+ case '<': /* "big heredoc" support */
+ full_write1_str(optarg);
+ _exit(0);
+ case '$': {
+ unsigned long long empty_trap_mask;
+
+ G.root_pid = bb_strtou(optarg, &optarg, 16);
+ optarg++;
+ G.root_ppid = bb_strtou(optarg, &optarg, 16);
+ optarg++;
+ G.last_bg_pid = bb_strtou(optarg, &optarg, 16);
+ optarg++;
+ G.last_exitcode = bb_strtou(optarg, &optarg, 16);
+ optarg++;
+ builtin_argc = bb_strtou(optarg, &optarg, 16);
+ optarg++;
+ empty_trap_mask = bb_strtoull(optarg, &optarg, 16);
+ if (empty_trap_mask != 0) {
+ IF_HUSH_TRAP(int sig;)
+ install_special_sighandlers();
+# if ENABLE_HUSH_TRAP
+ G_traps = xzalloc(sizeof(G_traps[0]) * NSIG);
+ for (sig = 1; sig < NSIG; sig++) {
+ if (empty_trap_mask & (1LL << sig)) {
+ G_traps[sig] = xzalloc(1); /* == xstrdup(""); */
+ install_sighandler(sig, SIG_IGN);
+ }
+ }
+# endif
+ }
+# if ENABLE_HUSH_LOOPS
+ optarg++;
+ G.depth_of_loop = bb_strtou(optarg, &optarg, 16);
+# endif
+ /* Suppress "killed by signal" message, -$ hack is used
+ * for subshells: echo `sh -c 'kill -9 $$'`
+ * should be silent.
+ */
+ IF_HUSH_JOB(G.run_list_level = 1;)
+# if ENABLE_HUSH_FUNCTIONS
+ /* nommu uses re-exec trick for "... | func | ...",
+ * should allow "return".
+ * This accidentally allows returns in subshells.
+ */
+ G_flag_return_in_progress = -1;
+# endif
+ break;
+ }
+ case 'R':
+ case 'V':
+ set_local_var(xstrdup(optarg), opt == 'R' ? SETFLAG_MAKE_RO : 0);
+ break;
+# if ENABLE_HUSH_FUNCTIONS
+ case 'F': {
+ struct function *funcp = new_function(optarg);
+ /* funcp->name is already set to optarg */
+ /* funcp->body is set to NULL. It's a special case. */
+ funcp->body_as_string = argv[optind];
+ optind++;
+ break;
+ }
+# endif
+#endif
+ /*case '?': invalid option encountered (set_mode('?') will fail) */
+ /*case 'n':*/
+ /*case 'x':*/
+ /*case 'e':*/
+ default:
+ if (set_mode(1, opt, NULL) == 0) /* no error */
+ break;
+ bb_show_usage();
+ }
+ } /* option parsing loop */
+
+ /* Skip options. Try "hush -l": $1 should not be "-l"! */
+ G.global_argc = argc - (optind - 1);
+ G.global_argv = argv + (optind - 1);
+ G.global_argv[0] = argv[0];
+
+ /* If we are login shell... */
+ if (flags & OPT_login) {
+ const char *hp = NULL;
+ HFILE *input;
+
+ debug_printf("sourcing /etc/profile\n");
+ input = hfopen("/etc/profile");
+ run_profile:
+ if (input != NULL) {
+ install_special_sighandlers();
+ parse_and_run_file(input);
+ hfclose(input);
+ }
+ /* bash: after sourcing /etc/profile,
+ * tries to source (in the given order):
+ * ~/.bash_profile, ~/.bash_login, ~/.profile,
+ * stopping on first found. --noprofile turns this off.
+ * bash also sources ~/.bash_logout on exit.
+ * If called as sh, skips .bash_XXX files.
+ */
+ if (!hp) { /* unless we looped on the "goto" already */
+ hp = get_local_var_value("HOME");
+ if (hp && hp[0]) {
+ debug_printf("sourcing ~/.profile\n");
+ hp = concat_path_file(hp, ".profile");
+ input = hfopen(hp);
+ free((char*)hp);
+ goto run_profile;
+ }
+ }
+ }
+
+ /* -c takes effect *after* -l */
+ if (G.opt_c) {
+ /* Possibilities:
+ * sh ... -c 'script'
+ * sh ... -c 'script' ARG0 [ARG1...]
+ * On NOMMU, if builtin_argc != 0,
+ * sh ... -c 'builtin' BARGV... "" ARG0 [ARG1...]
+ * "" needs to be replaced with NULL
+ * and BARGV vector fed to builtin function.
+ * Note: the form without ARG0 never happens:
+ * sh ... -c 'builtin' BARGV... ""
+ */
+ char *script;
+
+ install_special_sighandlers();
+
+ G.global_argc--;
+ G.global_argv++;
+#if !BB_MMU
+ if (builtin_argc) {
+ /* -c 'builtin' [BARGV...] "" ARG0 [ARG1...] */
+ const struct built_in_command *x;
+ x = find_builtin(G.global_argv[0]);
+ if (x) { /* paranoia */
+ argv = G.global_argv;
+ G.global_argc -= builtin_argc + 1; /* skip [BARGV...] "" */
+ G.global_argv += builtin_argc + 1;
+ G.global_argv[-1] = NULL; /* replace "" */
+ G.last_exitcode = x->b_function(argv);
+ }
+ goto final_return;
+ }
+#endif
+
+ script = G.global_argv[0];
+ if (!script)
+ bb_error_msg_and_die(bb_msg_requires_arg, "-c");
+ if (!G.global_argv[1]) {
+ /* -c 'script' (no params): prevent empty $0 */
+ G.global_argv[0] = argv[0];
+ } else { /* else -c 'script' ARG0 [ARG1...]: $0 is ARG0 */
+ G.global_argc--;
+ G.global_argv++;
+ }
+ parse_and_run_string(script);
+ goto final_return;
+ }
+
+ /* -s is: hush -s ARGV1 ARGV2 (no SCRIPT) */
+ if (!G.opt_s && G.global_argv[1]) {
+ HFILE *input;
+ /*
+ * "bash <script>" (which is never interactive (unless -i?))
+ * sources $BASH_ENV here (without scanning $PATH).
+ * If called as sh, does the same but with $ENV.
+ * Also NB, per POSIX, $ENV should undergo parameter expansion.
+ */
+ G.global_argc--;
+ G.global_argv++;
+ debug_printf("running script '%s'\n", G.global_argv[0]);
+ xfunc_error_retval = 127; /* for "hush /does/not/exist" case */
+ input = hfopen(G.global_argv[0]);
+ if (!input) {
+ bb_simple_perror_msg_and_die(G.global_argv[0]);
+ }
+ xfunc_error_retval = 1;
+ install_special_sighandlers();
+ parse_and_run_file(input);
+#if ENABLE_FEATURE_CLEAN_UP
+ hfclose(input);
+#endif
+ goto final_return;
+ }
+ /* "implicit" -s: bare interactive hush shows 's' in $- */
+ G.opt_s = 1;
+
+ /* Up to here, shell was non-interactive. Now it may become one.
+ * NB: don't forget to (re)run install_special_sighandlers() as needed.
+ */
+
+ /* A shell is interactive if the '-i' flag was given,
+ * or if all of the following conditions are met:
+ * no -c command
+ * no arguments remaining or the -s flag given
+ * standard input is a terminal
+ * standard output is a terminal
+ * Refer to Posix.2, the description of the 'sh' utility.
+ */
+#if ENABLE_HUSH_JOB
+ if (isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)) {
+ G_saved_tty_pgrp = tcgetpgrp(STDIN_FILENO);
+ debug_printf("saved_tty_pgrp:%d\n", G_saved_tty_pgrp);
+ if (G_saved_tty_pgrp < 0)
+ G_saved_tty_pgrp = 0;
+
+ /* try to dup stdin to high fd#, >= 255 */
+ G_interactive_fd = dup_CLOEXEC(STDIN_FILENO, 254);
+ if (G_interactive_fd < 0) {
+ /* try to dup to any fd */
+ G_interactive_fd = dup(STDIN_FILENO);
+ if (G_interactive_fd < 0) {
+ /* give up */
+ G_interactive_fd = 0;
+ G_saved_tty_pgrp = 0;
+ }
+ }
+ }
+ debug_printf("interactive_fd:%d\n", G_interactive_fd);
+ if (G_interactive_fd) {
+ close_on_exec_on(G_interactive_fd);
+
+ if (G_saved_tty_pgrp) {
+ /* If we were run as 'hush &', sleep until we are
+ * in the foreground (tty pgrp == our pgrp).
+ * If we get started under a job aware app (like bash),
+ * make sure we are now in charge so we don't fight over
+ * who gets the foreground */
+ while (1) {
+ pid_t shell_pgrp = getpgrp();
+ G_saved_tty_pgrp = tcgetpgrp(G_interactive_fd);
+ if (G_saved_tty_pgrp == shell_pgrp)
+ break;
+ /* send TTIN to ourself (should stop us) */
+ kill(- shell_pgrp, SIGTTIN);
+ }
+ }
+
+ /* Install more signal handlers */
+ install_special_sighandlers();
+
+ if (G_saved_tty_pgrp) {
+ /* Set other signals to restore saved_tty_pgrp */
+ install_fatal_sighandlers();
+ /* Put ourselves in our own process group
+ * (bash, too, does this only if ctty is available) */
+ bb_setpgrp(); /* is the same as setpgid(our_pid, our_pid); */
+ /* Grab control of the terminal */
+ tcsetpgrp(G_interactive_fd, cached_getpid);
+ }
+ enable_restore_tty_pgrp_on_exit();
+
+# if ENABLE_FEATURE_EDITING
+ G.line_input_state = new_line_input_t(FOR_SHELL);
+# if EDITING_HAS_get_exe_name
+ G.line_input_state->get_exe_name = get_builtin_name;
+# endif
+# endif
+# if ENABLE_HUSH_SAVEHISTORY && MAX_HISTORY > 0
+ {
+ const char *hp = get_local_var_value("HISTFILE");
+ if (!hp) {
+ hp = get_local_var_value("HOME");
+ if (hp)
+ hp = concat_path_file(hp, ".hush_history");
+ } else {
+ hp = xstrdup(hp);
+ }
+ if (hp) {
+ G.line_input_state->hist_file = hp;
+ //set_local_var(xasprintf("HISTFILE=%s", ...));
+ }
+# if ENABLE_FEATURE_SH_HISTFILESIZE
+ hp = get_local_var_value("HISTFILESIZE");
+ G.line_input_state->max_history = size_from_HISTFILESIZE(hp);
+# endif
+ }
+# endif
+ } else {
+ install_special_sighandlers();
+ }
+#elif ENABLE_HUSH_INTERACTIVE
+ /* No job control compiled in, only prompt/line editing */
+ if (isatty(STDIN_FILENO) && isatty(STDOUT_FILENO)) {
+ G_interactive_fd = dup_CLOEXEC(STDIN_FILENO, 254);
+ if (G_interactive_fd < 0) {
+ /* try to dup to any fd */
+ G_interactive_fd = dup_CLOEXEC(STDIN_FILENO, -1);
+ if (G_interactive_fd < 0)
+ /* give up */
+ G_interactive_fd = 0;
+ }
+ }
+ if (G_interactive_fd) {
+ close_on_exec_on(G_interactive_fd);
+ }
+ install_special_sighandlers();
+#else
+ /* We have interactiveness code disabled */
+ install_special_sighandlers();
+#endif
+ /* bash:
+ * if interactive but not a login shell, sources ~/.bashrc
+ * (--norc turns this off, --rcfile <file> overrides)
+ */
+
+ if (G_interactive_fd) {
+#if ENABLE_HUSH_INTERACTIVE && ENABLE_FEATURE_EDITING_FANCY_PROMPT
+ /* Set (but not export) PS1/2 unless already set */
+ if (!get_local_var_value("PS1"))
+ set_local_var_from_halves("PS1", "\\w \\$ ");
+ if (!get_local_var_value("PS2"))
+ set_local_var_from_halves("PS2", "> ");
+#endif
+ if (!ENABLE_FEATURE_SH_EXTRA_QUIET) {
+ /* note: ash and hush share this string */
+ printf("\n\n%s %s\n"
+ IF_HUSH_HELP("Enter 'help' for a list of built-in commands.\n")
+ "\n",
+ bb_banner,
+ "hush - the humble shell"
+ );
+ }
+ }
+
+ parse_and_run_file(hfopen(NULL)); /* stdin */
+
+ final_return:
+ hush_exit(G.last_exitcode);
+}
+
+
+/*
+ * Built-ins
+ */
+static int FAST_FUNC builtin_true(char **argv UNUSED_PARAM)
+{
+ return 0;
+}
+
+#if ENABLE_HUSH_TEST || ENABLE_HUSH_ECHO || ENABLE_HUSH_PRINTF || ENABLE_HUSH_KILL
+static NOINLINE int run_applet_main(char **argv, int (*applet_main_func)(int argc, char **argv))
+{
+ int argc = string_array_len(argv);
+ return applet_main_func(argc, argv);
+}
+#endif
+#if ENABLE_HUSH_TEST || BASH_TEST2
+static int FAST_FUNC builtin_test(char **argv)
+{
+ return run_applet_main(argv, test_main);
+}
+#endif
+#if ENABLE_HUSH_ECHO
+static int FAST_FUNC builtin_echo(char **argv)
+{
+ return run_applet_main(argv, echo_main);
+}
+#endif
+#if ENABLE_HUSH_PRINTF
+static int FAST_FUNC builtin_printf(char **argv)
+{
+ return run_applet_main(argv, printf_main);
+}
+#endif
+
+#if ENABLE_HUSH_HELP
+static int FAST_FUNC builtin_help(char **argv UNUSED_PARAM)
+{
+ const struct built_in_command *x;
+
+ printf(
+ "Built-in commands:\n"
+ "------------------\n");
+ for (x = bltins1; x != &bltins1[ARRAY_SIZE(bltins1)]; x++) {
+ if (x->b_descr)
+ printf("%-10s%s\n", x->b_cmd, x->b_descr);
+ }
+ return EXIT_SUCCESS;
+}
+#endif
+
+#if MAX_HISTORY && ENABLE_FEATURE_EDITING
+static int FAST_FUNC builtin_history(char **argv UNUSED_PARAM)
+{
+ show_history(G.line_input_state);
+ return EXIT_SUCCESS;
+}
+#endif
+
+static char **skip_dash_dash(char **argv)
+{
+ argv++;
+ if (argv[0] && argv[0][0] == '-' && argv[0][1] == '-' && argv[0][2] == '\0')
+ argv++;
+ return argv;
+}
+
+static int FAST_FUNC builtin_cd(char **argv)
+{
+ const char *newdir;
+
+ argv = skip_dash_dash(argv);
+ newdir = argv[0];
+ if (newdir == NULL) {
+ /* bash does nothing (exitcode 0) if HOME is ""; if it's unset,
+ * bash says "bash: cd: HOME not set" and does nothing
+ * (exitcode 1)
+ */
+ const char *home = get_local_var_value("HOME");
+ newdir = home ? home : "/";
+ }
+ if (chdir(newdir)) {
+ /* Mimic bash message exactly */
+ bb_perror_msg("cd: %s", newdir);
+ return EXIT_FAILURE;
+ }
+ /* Read current dir (get_cwd(1) is inside) and set PWD.
+ * Note: do not enforce exporting. If PWD was unset or unexported,
+ * set it again, but do not export. bash does the same.
+ */
+ set_pwd_var(/*flag:*/ 0);
+ return EXIT_SUCCESS;
+}
+
+static int FAST_FUNC builtin_pwd(char **argv UNUSED_PARAM)
+{
+ puts(get_cwd(0));
+ return EXIT_SUCCESS;
+}
+
+static int FAST_FUNC builtin_eval(char **argv)
+{
+ argv = skip_dash_dash(argv);
+
+ if (!argv[0])
+ return EXIT_SUCCESS;
+
+ IF_HUSH_MODE_X(G.x_mode_depth++;)
+ //bb_error_msg("%s: ++x_mode_depth=%d", __func__, G.x_mode_depth);
+ if (!argv[1]) {
+ /* bash:
+ * eval "echo Hi; done" ("done" is syntax error):
+ * "echo Hi" will not execute too.
+ */
+ parse_and_run_string(argv[0]);
+ } else {
+ /* "The eval utility shall construct a command by
+ * concatenating arguments together, separating
+ * each with a <space> character."
+ */
+ char *str, *p;
+ unsigned len = 0;
+ char **pp = argv;
+ do
+ len += strlen(*pp) + 1;
+ while (*++pp);
+ str = p = xmalloc(len);
+ pp = argv;
+ for (;;) {
+ p = stpcpy(p, *pp);
+ pp++;
+ if (!*pp)
+ break;
+ *p++ = ' ';
+ }
+ parse_and_run_string(str);
+ free(str);
+ }
+ IF_HUSH_MODE_X(G.x_mode_depth--;)
+ //bb_error_msg("%s: --x_mode_depth=%d", __func__, G.x_mode_depth);
+ return G.last_exitcode;
+}
+
+static int FAST_FUNC builtin_exec(char **argv)
+{
+ argv = skip_dash_dash(argv);
+ if (argv[0] == NULL)
+ return EXIT_SUCCESS; /* bash does this */
+
+ /* Careful: we can end up here after [v]fork. Do not restore
+ * tty pgrp then, only top-level shell process does that */
+ if (G_saved_tty_pgrp && getpid() == G.root_pid)
+ tcsetpgrp(G_interactive_fd, G_saved_tty_pgrp);
+
+ /* Saved-redirect fds, script fds and G_interactive_fd are still
+ * open here. However, they are all CLOEXEC, and execv below
+ * closes them. Try interactive "exec ls -l /proc/self/fd",
+ * it should show no extra open fds in the "ls" process.
+ * If we'd try to run builtins/NOEXECs, this would need improving.
+ */
+ //close_saved_fds_and_FILE_fds();
+
+ /* TODO: if exec fails, bash does NOT exit! We do.
+ * We'll need to undo trap cleanup (it's inside execvp_or_die)
+ * and tcsetpgrp, and this is inherently racy.
+ */
+ execvp_or_die(argv);
+}
+
+static int FAST_FUNC builtin_exit(char **argv)
+{
+ debug_printf_exec("%s()\n", __func__);
+
+ /* interactive bash:
+ * # trap "echo EEE" EXIT
+ * # exit
+ * exit
+ * There are stopped jobs.
+ * (if there are _stopped_ jobs, running ones don't count)
+ * # exit
+ * exit
+ * EEE (then bash exits)
+ *
+ * TODO: we can use G.exiting = -1 as indicator "last cmd was exit"
+ */
+
+ /* note: EXIT trap is run by hush_exit */
+ argv = skip_dash_dash(argv);
+ if (argv[0] == NULL) {
+#if ENABLE_HUSH_TRAP
+ if (G.pre_trap_exitcode >= 0) /* "exit" in trap uses $? from before the trap */
+ hush_exit(G.pre_trap_exitcode);
+#endif
+ hush_exit(G.last_exitcode);
+ }
+ /* mimic bash: exit 123abc == exit 255 + error msg */
+ xfunc_error_retval = 255;
+ /* bash: exit -2 == exit 254, no error msg */
+ hush_exit(xatoi(argv[0]) & 0xff);
+}
+
+#if ENABLE_HUSH_TYPE
+/* http://www.opengroup.org/onlinepubs/9699919799/utilities/type.html */
+static int FAST_FUNC builtin_type(char **argv)
+{
+ int ret = EXIT_SUCCESS;
+
+ while (*++argv) {
+ const char *type;
+ char *path = NULL;
+
+ if (0) {} /* make conditional compile easier below */
+ /*else if (find_alias(*argv))
+ type = "an alias";*/
+# if ENABLE_HUSH_FUNCTIONS
+ else if (find_function(*argv))
+ type = "a function";
+# endif
+ else if (find_builtin(*argv))
+ type = "a shell builtin";
+ else if ((path = find_in_path(*argv)) != NULL)
+ type = path;
+ else {
+ bb_error_msg("type: %s: not found", *argv);
+ ret = EXIT_FAILURE;
+ continue;
+ }
+
+ printf("%s is %s\n", *argv, type);
+ free(path);
+ }
+
+ return ret;
+}
+#endif
+
+#if ENABLE_HUSH_READ
+/* Interruptibility of read builtin in bash
+ * (tested on bash-4.2.8 by sending signals (not by ^C)):
+ *
+ * Empty trap makes read ignore corresponding signal, for any signal.
+ *
+ * SIGINT:
+ * - terminates non-interactive shell;
+ * - interrupts read in interactive shell;
+ * if it has non-empty trap:
+ * - executes trap and returns to command prompt in interactive shell;
+ * - executes trap and returns to read in non-interactive shell;
+ * SIGTERM:
+ * - is ignored (does not interrupt) read in interactive shell;
+ * - terminates non-interactive shell;
+ * if it has non-empty trap:
+ * - executes trap and returns to read;
+ * SIGHUP:
+ * - terminates shell (regardless of interactivity);
+ * if it has non-empty trap:
+ * - executes trap and returns to read;
+ * SIGCHLD from children:
+ * - does not interrupt read regardless of interactivity:
+ * try: sleep 1 & read x; echo $x
+ */
+static int FAST_FUNC builtin_read(char **argv)
+{
+ const char *r;
+ struct builtin_read_params params;
+
+ memset(¶ms, 0, sizeof(params));
+
+ /* "!": do not abort on errors.
+ * Option string must start with "sr" to match BUILTIN_READ_xxx
+ */
+ params.read_flags = getopt32(argv,
+# if BASH_READ_D
+ IF_NOT_HUSH_BASH_COMPAT("^")
+ "!srn:p:t:u:d:" IF_NOT_HUSH_BASH_COMPAT("\0" "-1"/*min 1 arg*/),
+ ¶ms.opt_n, ¶ms.opt_p, ¶ms.opt_t, ¶ms.opt_u, ¶ms.opt_d
+# else
+ IF_NOT_HUSH_BASH_COMPAT("^")
+ "!srn:p:t:u:" IF_NOT_HUSH_BASH_COMPAT("\0" "-1"/*min 1 arg*/),
+ ¶ms.opt_n, ¶ms.opt_p, ¶ms.opt_t, ¶ms.opt_u
+# endif
+//TODO: print "read: need variable name"
+//for the case of !BASH "read" with no args (now it fails silently)
+//(or maybe extend getopt32() to emit a message if "-1" fails)
+ );
+ if ((uint32_t)params.read_flags == (uint32_t)-1)
+ return EXIT_FAILURE;
+ argv += optind;
+ params.argv = argv;
+ params.setvar = set_local_var_from_halves;
+ params.ifs = get_local_var_value("IFS"); /* can be NULL */
+
+ again:
+ r = shell_builtin_read(¶ms);
+
+ if ((uintptr_t)r == 1 && errno == EINTR) {
+ unsigned sig = check_and_run_traps();
+ if (sig != SIGINT)
+ goto again;
+ }
+
+ if ((uintptr_t)r > 1) {
+ bb_simple_error_msg(r);
+ r = (char*)(uintptr_t)1;
+ }
+
+ return (uintptr_t)r;
+}
+#endif
+
+#if ENABLE_HUSH_UMASK
+static int FAST_FUNC builtin_umask(char **argv)
+{
+ int rc;
+ mode_t mask;
+
+ rc = 1;
+ mask = umask(0);
+ argv = skip_dash_dash(argv);
+ if (argv[0]) {
+ mode_t old_mask = mask;
+
+ /* numeric umasks are taken as-is */
+ /* symbolic umasks are inverted: "umask a=rx" calls umask(222) */
+ if (!isdigit(argv[0][0]))
+ mask ^= 0777;
+ mask = bb_parse_mode(argv[0], mask);
+ if (!isdigit(argv[0][0]))
+ mask ^= 0777;
+ if ((unsigned)mask > 0777) {
+ mask = old_mask;
+ /* bash messages:
+ * bash: umask: 'q': invalid symbolic mode operator
+ * bash: umask: 999: octal number out of range
+ */
+ bb_error_msg("%s: invalid mode '%s'", "umask", argv[0]);
+ rc = 0;
+ }
+ } else {
+ /* Mimic bash */
+ printf("%04o\n", (unsigned) mask);
+ /* fall through and restore mask which we set to 0 */
+ }
+ umask(mask);
+
+ return !rc; /* rc != 0 - success */
+}
+#endif
+
+#if ENABLE_HUSH_EXPORT || ENABLE_HUSH_TRAP
+static void print_escaped(const char *s)
+{
+ if (*s == '\'')
+ goto squote;
+ do {
+ const char *p = strchrnul(s, '\'');
+ /* print 'xxxx', possibly just '' */
+ printf("'%.*s'", (int)(p - s), s);
+ if (*p == '\0')
+ break;
+ s = p;
+ squote:
+ /* s points to '; print "'''...'''" */
+ putchar('"');
+ do putchar('\''); while (*++s == '\'');
+ putchar('"');
+ } while (*s);
+}
+#endif
+
+#if ENABLE_HUSH_EXPORT || ENABLE_HUSH_LOCAL || ENABLE_HUSH_READONLY
+static int helper_export_local(char **argv, unsigned flags)
+{
+ do {
+ char *name = *argv;
+ const char *name_end = endofname(name);
+
+ if (*name_end == '\0') {
+ struct variable *var, **vpp;
+
+ vpp = get_ptr_to_local_var(name, name_end - name);
+ var = vpp ? *vpp : NULL;
+
+ if (flags & SETFLAG_UNEXPORT) {
+ /* export -n NAME (without =VALUE) */
+ if (var) {
+ var->flg_export = 0;
+ debug_printf_env("%s: unsetenv '%s'\n", __func__, name);
+ unsetenv(name);
+ } /* else: export -n NOT_EXISTING_VAR: no-op */
+ continue;
+ }
+ if (flags & SETFLAG_EXPORT) {
+ /* export NAME (without =VALUE) */
+ if (var) {
+ var->flg_export = 1;
+ debug_printf_env("%s: putenv '%s'\n", __func__, var->varstr);
+ putenv(var->varstr);
+ continue;
+ }
+ }
+ if (flags & SETFLAG_MAKE_RO) {
+ /* readonly NAME (without =VALUE) */
+ if (var) {
+ var->flg_read_only = 1;
+ continue;
+ }
+ }
+# if ENABLE_HUSH_LOCAL
+ /* Is this "local" bltin? */
+ if (!(flags & (SETFLAG_EXPORT|SETFLAG_UNEXPORT|SETFLAG_MAKE_RO))) {
+ unsigned lvl = flags >> SETFLAG_VARLVL_SHIFT;
+ if (var && var->var_nest_level == lvl) {
+ /* "local x=abc; ...; local x" - ignore second local decl */
+ continue;
+ }
+ }
+# endif
+ /* Exporting non-existing variable.
+ * bash does not put it in environment,
+ * but remembers that it is exported,
+ * and does put it in env when it is set later.
+ * We just set it to "" and export.
+ */
+ /* Or, it's "local NAME" (without =VALUE).
+ * bash sets the value to "".
+ */
+ /* Or, it's "readonly NAME" (without =VALUE).
+ * bash remembers NAME and disallows its creation
+ * in the future.
+ */
+ name = xasprintf("%s=", name);
+ } else {
+ if (*name_end != '=') {
+ bb_error_msg("'%s': bad variable name", name);
+ /* do not parse following argv[]s: */
+ return 1;
+ }
+ /* (Un)exporting/making local NAME=VALUE */
+ name = xstrdup(name);
+ /* Testcase: export PS1='\w \$ ' */
+ unbackslash(name);
+ }
+ debug_printf_env("%s: set_local_var('%s')\n", __func__, name);
+ if (set_local_var(name, flags))
+ return EXIT_FAILURE;
+ } while (*++argv);
+ return EXIT_SUCCESS;
+}
+#endif
+
+#if ENABLE_HUSH_EXPORT
+static int FAST_FUNC builtin_export(char **argv)
+{
+ unsigned opt_unexport;
+
+# if ENABLE_HUSH_EXPORT_N
+ /* "!": do not abort on errors */
+ opt_unexport = getopt32(argv, "!n");
+ if (opt_unexport == (uint32_t)-1)
+ return EXIT_FAILURE;
+ argv += optind;
+# else
+ opt_unexport = 0;
+ argv++;
+# endif
+
+ if (argv[0] == NULL) {
+ char **e = environ;
+ if (e) {
+ while (*e) {
+# if 0
+ puts(*e++);
+# else
+ /* ash emits: export VAR='VAL'
+ * bash: declare -x VAR="VAL"
+ * we follow ash example */
+ const char *s = *e++;
+ const char *p = strchr(s, '=');
+
+ if (!p) /* wtf? take next variable */
+ continue;
+ /* export var= */
+ printf("export %.*s", (int)(p - s) + 1, s);
+ print_escaped(p + 1);
+ putchar('\n');
+# endif
+ }
+ /*fflush_all(); - done after each builtin anyway */
+ }
+ return EXIT_SUCCESS;
+ }
+
+ return helper_export_local(argv, opt_unexport ? SETFLAG_UNEXPORT : SETFLAG_EXPORT);
+}
+#endif
+
+#if ENABLE_HUSH_LOCAL
+static int FAST_FUNC builtin_local(char **argv)
+{
+ if (G.func_nest_level == 0) {
+ bb_error_msg("%s: not in a function", argv[0]);
+ return EXIT_FAILURE; /* bash compat */
+ }
+ argv++;
+ /* Since all builtins run in a nested variable level,
+ * need to use level - 1 here. Or else the variable will be removed at once
+ * after builtin returns.
+ */
+ return helper_export_local(argv, (G.var_nest_level - 1) << SETFLAG_VARLVL_SHIFT);
+}
+#endif
+
+#if ENABLE_HUSH_READONLY
+static int FAST_FUNC builtin_readonly(char **argv)
+{
+ argv++;
+ if (*argv == NULL) {
+ /* bash: readonly [-p]: list all readonly VARs
+ * (-p has no effect in bash)
+ */
+ struct variable *e;
+ for (e = G.top_var; e; e = e->next) {
+ if (e->flg_read_only) {
+//TODO: quote value: readonly VAR='VAL'
+ printf("readonly %s\n", e->varstr);
+ }
+ }
+ return EXIT_SUCCESS;
+ }
+ return helper_export_local(argv, SETFLAG_MAKE_RO);
+}
+#endif
+
+#if ENABLE_HUSH_UNSET
+/* http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#unset */
+static int FAST_FUNC builtin_unset(char **argv)
+{
+ int ret;
+ unsigned opts;
+
+ /* "!": do not abort on errors */
+ /* "+": stop at 1st non-option */
+ opts = getopt32(argv, "!+vf");
+ if (opts == (unsigned)-1)
+ return EXIT_FAILURE;
+ if (opts == 3) {
+ bb_simple_error_msg("unset: -v and -f are exclusive");
+ return EXIT_FAILURE;
+ }
+ argv += optind;
+
+ ret = EXIT_SUCCESS;
+ while (*argv) {
+ if (!(opts & 2)) { /* not -f */
+ if (unset_local_var(*argv)) {
+ /* unset <nonexistent_var> doesn't fail.
+ * Error is when one tries to unset RO var.
+ * Message was printed by unset_local_var. */
+ ret = EXIT_FAILURE;
+ }
+ }
+# if ENABLE_HUSH_FUNCTIONS
+ else {
+ unset_func(*argv);
+ }
+# endif
+ argv++;
+ }
+ return ret;
+}
+#endif
+
+#if ENABLE_HUSH_SET
+/* http://www.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#set
+ * built-in 'set' handler
+ * SUSv3 says:
+ * set [-abCefhmnuvx] [-o option] [argument...]
+ * set [+abCefhmnuvx] [+o option] [argument...]
+ * set -- [argument...]
+ * set -o
+ * set +o
+ * Implementations shall support the options in both their hyphen and
+ * plus-sign forms. These options can also be specified as options to sh.
+ * Examples:
+ * Write out all variables and their values: set
+ * Set $1, $2, and $3 and set "$#" to 3: set c a b
+ * Turn on the -x and -v options: set -xv
+ * Unset all positional parameters: set --
+ * Set $1 to the value of x, even if it begins with '-' or '+': set -- "$x"
+ * Set the positional parameters to the expansion of x, even if x expands
+ * with a leading '-' or '+': set -- $x
+ *
+ * So far, we only support "set -- [argument...]" and some of the short names.
+ */
+static int FAST_FUNC builtin_set(char **argv)
+{
+ int n;
+ char **pp, **g_argv;
+ char *arg = *++argv;
+
+ if (arg == NULL) {
+ struct variable *e;
+ for (e = G.top_var; e; e = e->next)
+ puts(e->varstr);
+ return EXIT_SUCCESS;
+ }
+
+ do {
+ if (strcmp(arg, "--") == 0) {
+ ++argv;
+ goto set_argv;
+ }
+ if (arg[0] != '+' && arg[0] != '-')
+ break;
+ for (n = 1; arg[n]; ++n) {
+ if (set_mode((arg[0] == '-'), arg[n], argv[1])) {
+ bb_error_msg("%s: %s: invalid option", "set", arg);
+ return EXIT_FAILURE;
+ }
+ if (arg[n] == 'o' && argv[1])
+ argv++;
+ }
+ } while ((arg = *++argv) != NULL);
+ /* Now argv[0] is 1st argument */
+
+ if (arg == NULL)
+ return EXIT_SUCCESS;
+ set_argv:
+
+ /* NB: G.global_argv[0] ($0) is never freed/changed */
+ g_argv = G.global_argv;
+ if (G.global_args_malloced) {
+ pp = g_argv;
+ while (*++pp)
+ free(*pp);
+ g_argv[1] = NULL;
+ } else {
+ G.global_args_malloced = 1;
+ pp = xzalloc(sizeof(pp[0]) * 2);
+ pp[0] = g_argv[0]; /* retain $0 */
+ g_argv = pp;
+ }
+ /* This realloc's G.global_argv */
+ G.global_argv = pp = add_strings_to_strings(g_argv, argv, /*dup:*/ 1);
+
+ G.global_argc = 1 + string_array_len(pp + 1);
+
+ return EXIT_SUCCESS;
+}
+#endif
+
+static int FAST_FUNC builtin_shift(char **argv)
+{
+ int n = 1;
+ argv = skip_dash_dash(argv);
+ if (argv[0]) {
+ n = bb_strtou(argv[0], NULL, 10);
+ if (errno || n < 0) {
+ /* shared string with ash.c */
+ bb_error_msg("Illegal number: %s", argv[0]);
+ /*
+ * ash aborts in this case.
+ * bash prints error message and set $? to 1.
+ * Interestingly, for "shift 99999" bash does not
+ * print error message, but does set $? to 1
+ * (and does no shifting at all).
+ */
+ }
+ }
+ if (n >= 0 && n < G.global_argc) {
+ if (G_global_args_malloced) {
+ int m = 1;
+ while (m <= n)
+ free(G.global_argv[m++]);
+ }
+ G.global_argc -= n;
+ memmove(&G.global_argv[1], &G.global_argv[n+1],
+ G.global_argc * sizeof(G.global_argv[0]));
+ return EXIT_SUCCESS;
+ }
+ return EXIT_FAILURE;
+}
+
+#if ENABLE_HUSH_GETOPTS
+static int FAST_FUNC builtin_getopts(char **argv)
+{
+/* http://pubs.opengroup.org/onlinepubs/9699919799/utilities/getopts.html
+
+TODO:
+If a required argument is not found, and getopts is not silent,
+a question mark (?) is placed in VAR, OPTARG is unset, and a
+diagnostic message is printed. If getopts is silent, then a
+colon (:) is placed in VAR and OPTARG is set to the option
+character found.
+
+Test that VAR is a valid variable name?
+
+"Whenever the shell is invoked, OPTIND shall be initialized to 1"
+*/
+ char cbuf[2];
+ const char *cp, *optstring, *var;
+ int c, n, exitcode, my_opterr;
+ unsigned count;
+
+ optstring = *++argv;
+ if (!optstring || !(var = *++argv)) {
+ bb_simple_error_msg("usage: getopts OPTSTRING VAR [ARGS]");
+ return EXIT_FAILURE;
+ }
+
+ if (argv[1])
+ argv[0] = G.global_argv[0]; /* for error messages in getopt() */
+ else
+ argv = G.global_argv;
+ cbuf[1] = '\0';
+
+ my_opterr = 0;
+ if (optstring[0] != ':') {
+ cp = get_local_var_value("OPTERR");
+ /* 0 if "OPTERR=0", 1 otherwise */
+ my_opterr = (!cp || NOT_LONE_CHAR(cp, '0'));
+ }
+
+ /* getopts stops on first non-option. Add "+" to force that */
+ /*if (optstring[0] != '+')*/ {
+ char *s = alloca(strlen(optstring) + 2);
+ sprintf(s, "+%s", optstring);
+ optstring = s;
+ }
+
+ /* Naively, now we should just
+ * cp = get_local_var_value("OPTIND");
+ * optind = cp ? atoi(cp) : 0;
+ * optarg = NULL;
+ * opterr = my_opterr;
+ * c = getopt(string_array_len(argv), argv, optstring);
+ * and be done? Not so fast...
+ * Unlike normal getopt() usage in C programs, here
+ * each successive call will (usually) have the same argv[] CONTENTS,
+ * but not the ADDRESSES. Worse yet, it's possible that between
+ * invocations of "getopts", there will be calls to shell builtins
+ * which use getopt() internally. Example:
+ * while getopts "abc" RES -a -bc -abc de; do
+ * unset -ff func
+ * done
+ * This would not work correctly: getopt() call inside "unset"
+ * modifies internal libc state which is tracking position in
+ * multi-option strings ("-abc"). At best, it can skip options
+ * or return the same option infinitely. With glibc implementation
+ * of getopt(), it would use outright invalid pointers and return
+ * garbage even _without_ "unset" mangling internal state.
+ *
+ * We resort to resetting getopt() state and calling it N times,
+ * until we get Nth result (or failure).
+ * (N == G.getopt_count is reset to 0 whenever OPTIND is [un]set).
+ */
+ GETOPT_RESET();
+ count = 0;
+ n = string_array_len(argv);
+ do {
+ optarg = NULL;
+ opterr = (count < G.getopt_count) ? 0 : my_opterr;
+ c = getopt(n, argv, optstring);
+ if (c < 0)
+ break;
+ count++;
+ } while (count <= G.getopt_count);
+
+ /* Set OPTIND. Prevent resetting of the magic counter! */
+ set_local_var_from_halves("OPTIND", utoa(optind));
+ G.getopt_count = count; /* "next time, give me N+1'th result" */
+ GETOPT_RESET(); /* just in case */
+
+ /* Set OPTARG */
+ /* Always set or unset, never left as-is, even on exit/error:
+ * "If no option was found, or if the option that was found
+ * does not have an option-argument, OPTARG shall be unset."
+ */
+ cp = optarg;
+ if (c == '?') {
+ /* If ":optstring" and unknown option is seen,
+ * it is stored to OPTARG.
+ */
+ if (optstring[1] == ':') {
+ cbuf[0] = optopt;
+ cp = cbuf;
+ }
+ }
+ if (cp)
+ set_local_var_from_halves("OPTARG", cp);
+ else
+ unset_local_var("OPTARG");
+
+ /* Convert -1 to "?" */
+ exitcode = EXIT_SUCCESS;
+ if (c < 0) { /* -1: end of options */
+ exitcode = EXIT_FAILURE;
+ c = '?';
+ }
+
+ /* Set VAR */
+ cbuf[0] = c;
+ set_local_var_from_halves(var, cbuf);
+
+ return exitcode;
+}
+#endif
+
+static int FAST_FUNC builtin_source(char **argv)
+{
+ char *arg_path, *filename;
+ HFILE *input;
+ save_arg_t sv;
+ char *args_need_save;
+#if ENABLE_HUSH_FUNCTIONS
+ smallint sv_flg;
+#endif
+
+ argv = skip_dash_dash(argv);
+ filename = argv[0];
+ if (!filename) {
+ /* bash says: "bash: .: filename argument required" */
+ return 2; /* bash compat */
+ }
+ arg_path = NULL;
+ if (!strchr(filename, '/')) {
+ arg_path = find_in_path(filename);
+ if (arg_path)
+ filename = arg_path;
+ else if (!ENABLE_HUSH_BASH_SOURCE_CURDIR) {
+ errno = ENOENT;
+ bb_simple_perror_msg(filename);
+ return EXIT_FAILURE;
+ }
+ }
+ input = hfopen(filename);
+ free(arg_path);
+ if (!input) {
+ bb_perror_msg("%s", filename);
+ /* POSIX: non-interactive shell should abort here,
+ * not merely fail. So far no one complained :)
+ */
+ return EXIT_FAILURE;
+ }
+
+#if ENABLE_HUSH_FUNCTIONS
+ sv_flg = G_flag_return_in_progress;
+ /* "we are inside sourced file, ok to use return" */
+ G_flag_return_in_progress = -1;
+#endif
+ args_need_save = argv[1]; /* used as a boolean variable */
+ if (args_need_save)
+ save_and_replace_G_args(&sv, argv);
+
+ /* "false; . ./empty_line; echo Zero:$?" should print 0 */
+ G.last_exitcode = 0;
+ parse_and_run_file(input);
+ hfclose(input);
+
+ if (args_need_save) /* can't use argv[1] instead: "shift" can mangle it */
+ restore_G_args(&sv, argv);
+#if ENABLE_HUSH_FUNCTIONS
+ G_flag_return_in_progress = sv_flg;
+#endif
+
+ return G.last_exitcode;
+}
+
+#if ENABLE_HUSH_TRAP
+static int FAST_FUNC builtin_trap(char **argv)
+{
+ int sig;
+ char *new_cmd;
+
+ if (!G_traps)
+ G_traps = xzalloc(sizeof(G_traps[0]) * NSIG);
+
+ argv++;
+ if (!*argv) {
+ int i;
+ /* No args: print all trapped */
+ for (i = 0; i < NSIG; ++i) {
+ if (G_traps[i]) {
+ printf("trap -- ");
+ print_escaped(G_traps[i]);
+ /* note: bash adds "SIG", but only if invoked
+ * as "bash". If called as "sh", or if set -o posix,
+ * then it prints short signal names.
+ * We are printing short names: */
+ printf(" %s\n", get_signame(i));
+ }
+ }
+ /*fflush_all(); - done after each builtin anyway */
+ return EXIT_SUCCESS;
+ }
+
+ new_cmd = NULL;
+ /* If first arg is a number: reset all specified signals */
+ sig = bb_strtou(*argv, NULL, 10);
+ if (errno == 0) {
+ int ret;
+ process_sig_list:
+ ret = EXIT_SUCCESS;
+ while (*argv) {
+ sighandler_t handler;
+
+ sig = get_signum(*argv++);
+ if (sig < 0) {
+ ret = EXIT_FAILURE;
+ /* Mimic bash message exactly */
+ bb_error_msg("trap: %s: invalid signal specification", argv[-1]);
+ continue;
+ }
+
+ free(G_traps[sig]);
+ G_traps[sig] = xstrdup(new_cmd);
+
+ debug_printf("trap: setting SIG%s (%i) to '%s'\n",
+ get_signame(sig), sig, G_traps[sig]);
+
+ /* There is no signal for 0 (EXIT) */
+ if (sig == 0)
+ continue;
+
+ if (new_cmd)
+ handler = (new_cmd[0] ? record_pending_signo : SIG_IGN);
+ else
+ /* We are removing trap handler */
+ handler = pick_sighandler(sig);
+ install_sighandler(sig, handler);
+ }
+ return ret;
+ }
+
+ if (!argv[1]) { /* no second arg */
+ bb_simple_error_msg("trap: invalid arguments");
+ return EXIT_FAILURE;
+ }
+
+ /* First arg is "-": reset all specified to default */
+ /* First arg is "--": skip it, the rest is "handler SIGs..." */
+ /* Everything else: set arg as signal handler
+ * (includes "" case, which ignores signal) */
+ if (argv[0][0] == '-') {
+ if (argv[0][1] == '\0') { /* "-" */
+ /* new_cmd remains NULL: "reset these sigs" */
+ goto reset_traps;
+ }
+ if (argv[0][1] == '-' && argv[0][2] == '\0') { /* "--" */
+ argv++;
+ }
+ /* else: "-something", no special meaning */
+ }
+ new_cmd = *argv;
+ reset_traps:
+ argv++;
+ goto process_sig_list;
+}
+#endif
+
+#if ENABLE_HUSH_JOB
+static struct pipe *parse_jobspec(const char *str)
+{
+ struct pipe *pi;
+ unsigned jobnum;
+
+ if (sscanf(str, "%%%u", &jobnum) != 1) {
+ if (str[0] != '%'
+ || (str[1] != '%' && str[1] != '+' && str[1] != '\0')
+ ) {
+ bb_error_msg("bad argument '%s'", str);
+ return NULL;
+ }
+ /* It is "%%", "%+" or "%" - current job */
+ jobnum = G.last_jobid;
+ if (jobnum == 0) {
+ bb_simple_error_msg("no current job");
+ return NULL;
+ }
+ }
+ for (pi = G.job_list; pi; pi = pi->next) {
+ if (pi->jobid == jobnum) {
+ return pi;
+ }
+ }
+ bb_error_msg("%u: no such job", jobnum);
+ return NULL;
+}
+
+static int FAST_FUNC builtin_jobs(char **argv UNUSED_PARAM)
+{
+ struct pipe *job;
+ const char *status_string;
+
+ checkjobs(NULL, 0 /*(no pid to wait for)*/);
+ for (job = G.job_list; job; job = job->next) {
+ if (job->alive_cmds == job->stopped_cmds)
+ status_string = "Stopped";
+ else
+ status_string = "Running";
+
+ printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->cmdtext);
+ }
+
+ clean_up_last_dead_job();
+
+ return EXIT_SUCCESS;
+}
+
+/* built-in 'fg' and 'bg' handler */
+static int FAST_FUNC builtin_fg_bg(char **argv)
+{
+ int i;
+ struct pipe *pi;
+
+ if (!G_interactive_fd)
+ return EXIT_FAILURE;
+
+ /* If they gave us no args, assume they want the last backgrounded task */
+ if (!argv[1]) {
+ for (pi = G.job_list; pi; pi = pi->next) {
+ if (pi->jobid == G.last_jobid) {
+ goto found;
+ }
+ }
+ bb_error_msg("%s: no current job", argv[0]);
+ return EXIT_FAILURE;
+ }
+
+ pi = parse_jobspec(argv[1]);
+ if (!pi)
+ return EXIT_FAILURE;
+ found:
+ /* TODO: bash prints a string representation
+ * of job being foregrounded (like "sleep 1 | cat") */
+ if (argv[0][0] == 'f' && G_saved_tty_pgrp) {
+ /* Put the job into the foreground. */
+ tcsetpgrp(G_interactive_fd, pi->pgrp);
+ }
+
+ /* Restart the processes in the job */
+ debug_printf_jobs("reviving %d procs, pgrp %d\n", pi->num_cmds, pi->pgrp);
+ for (i = 0; i < pi->num_cmds; i++) {
+ debug_printf_jobs("reviving pid %d\n", pi->cmds[i].pid);
+ }
+ pi->stopped_cmds = 0;
+
+ i = kill(- pi->pgrp, SIGCONT);
+ if (i < 0) {
+ if (errno == ESRCH) {
+ delete_finished_job(pi);
+ return EXIT_SUCCESS;
+ }
+ bb_simple_perror_msg("kill (SIGCONT)");
+ }
+
+ if (argv[0][0] == 'f') {
+ remove_job_from_table(pi); /* FG job shouldn't be in job table */
+ return checkjobs_and_fg_shell(pi);
+ }
+ return EXIT_SUCCESS;
+}
+#endif
+
+#if ENABLE_HUSH_KILL
+static int FAST_FUNC builtin_kill(char **argv)
+{
+ int ret = 0;
+
+# if ENABLE_HUSH_JOB
+ if (argv[1] && strcmp(argv[1], "-l") != 0) {
+ int i = 1;
+
+ do {
+ struct pipe *pi;
+ char *dst;
+ int j, n;
+
+ if (argv[i][0] != '%')
+ continue;
+ /*
+ * "kill %N" - job kill
+ * Converting to pgrp / pid kill
+ */
+ pi = parse_jobspec(argv[i]);
+ if (!pi) {
+ /* Eat bad jobspec */
+ j = i;
+ do {
+ j++;
+ argv[j - 1] = argv[j];
+ } while (argv[j]);
+ ret = 1;
+ i--;
+ continue;
+ }
+ /*
+ * In jobs started under job control, we signal
+ * entire process group by kill -PGRP_ID.
+ * This happens, f.e., in interactive shell.
+ *
+ * Otherwise, we signal each child via
+ * kill PID1 PID2 PID3.
+ * Testcases:
+ * sh -c 'sleep 1|sleep 1 & kill %1'
+ * sh -c 'true|sleep 2 & sleep 1; kill %1'
+ * sh -c 'true|sleep 1 & sleep 2; kill %1'
+ */
+ n = G_interactive_fd ? 1 : pi->num_cmds;
+ dst = alloca(n * sizeof(int)*4);
+ argv[i] = dst;
+ if (G_interactive_fd)
+ dst += sprintf(dst, " -%u", (int)pi->pgrp);
+ else for (j = 0; j < n; j++) {
+ struct command *cmd = &pi->cmds[j];
+ /* Skip exited members of the job */
+ if (cmd->pid == 0)
+ continue;
+ /*
+ * kill_main has matching code to expect
+ * leading space. Needed to not confuse
+ * negative pids with "kill -SIGNAL_NO" syntax
+ */
+ dst += sprintf(dst, " %u", (int)cmd->pid);
+ }
+ *dst = '\0';
+ } while (argv[++i]);
+ }
+# endif
+
+ if (argv[1] || ret == 0) {
+ ret = run_applet_main(argv, kill_main);
+ }
+ /* else: ret = 1, "kill %bad_jobspec" case */
+ return ret;
+}
+#endif
+
+#if ENABLE_HUSH_WAIT
+/* http://www.opengroup.org/onlinepubs/9699919799/utilities/wait.html */
+# if !ENABLE_HUSH_JOB
+# define wait_for_child_or_signal(pipe,pid) wait_for_child_or_signal(pid)
+# endif
+static int wait_for_child_or_signal(struct pipe *waitfor_pipe, pid_t waitfor_pid)
+{
+ int ret = 0;
+ for (;;) {
+ int sig;
+ sigset_t oldset;
+
+ if (!sigisemptyset(&G.pending_set))
+ goto check_sig;
+
+ /* waitpid is not interruptible by SA_RESTARTed
+ * signals which we use. Thus, this ugly dance:
+ */
+
+ /* Make sure possible SIGCHLD is stored in kernel's
+ * pending signal mask before we call waitpid.
+ * Or else we may race with SIGCHLD, lose it,
+ * and get stuck in sigsuspend...
+ */
+ sigfillset(&oldset); /* block all signals, remember old set */
+ sigprocmask2(SIG_SETMASK, &oldset);
+
+ if (!sigisemptyset(&G.pending_set)) {
+ /* Crap! we raced with some signal! */
+ goto restore;
+ }
+
+ /*errno = 0; - checkjobs does this */
+/* Can't pass waitfor_pipe into checkjobs(): it won't be interruptible */
+ ret = checkjobs(NULL, waitfor_pid); /* waitpid(WNOHANG) inside */
+ debug_printf_exec("checkjobs:%d\n", ret);
+# if ENABLE_HUSH_JOB
+ if (waitfor_pipe) {
+ int rcode = job_exited_or_stopped(waitfor_pipe);
+ debug_printf_exec("job_exited_or_stopped:%d\n", rcode);
+ if (rcode >= 0) {
+ ret = rcode;
+ sigprocmask(SIG_SETMASK, &oldset, NULL);
+ break;
+ }
+ }
+# endif
+ /* if ECHILD, there are no children (ret is -1 or 0) */
+ /* if ret == 0, no children changed state */
+ /* if ret != 0, it's exitcode+1 of exited waitfor_pid child */
+ if (errno == ECHILD || ret) {
+ ret--;
+ if (ret < 0) /* if ECHILD, may need to fix "ret" */
+ ret = 0;
+# if ENABLE_HUSH_BASH_COMPAT
+ if (waitfor_pid == -1 && errno == ECHILD) {
+ /* exitcode of "wait -n" with no children is 127, not 0 */
+ ret = 127;
+ }
+# endif
+ sigprocmask(SIG_SETMASK, &oldset, NULL);
+ break;
+ }
+ /* Wait for SIGCHLD or any other signal */
+ /* It is vitally important for sigsuspend that SIGCHLD has non-DFL handler! */
+ /* Note: sigsuspend invokes signal handler */
+ sigsuspend(&oldset);
+ /* ^^^ add "sigdelset(&oldset, SIGCHLD)" before sigsuspend
+ * to make sure SIGCHLD is not masked off?
+ * It was reported that this:
+ * fn() { : | return; }
+ * shopt -s lastpipe
+ * fn
+ * exec hush SCRIPT
+ * under bash 4.4.23 runs SCRIPT with SIGCHLD masked,
+ * making "wait" commands in SCRIPT block forever.
+ */
+ restore:
+ sigprocmask(SIG_SETMASK, &oldset, NULL);
+ check_sig:
+ /* So, did we get a signal? */
+ sig = check_and_run_traps();
+ if (sig /*&& sig != SIGCHLD - always true */) {
+ /* Do this for any (non-ignored) signal, not only for ^C */
+ ret = 128 | sig;
+ break;
+ }
+ /* SIGCHLD, or no signal, or ignored one, such as SIGQUIT. Repeat */
+ }
+ return ret;
+}
+
+static int FAST_FUNC builtin_wait(char **argv)
+{
+ int ret;
+ int status;
+
+ argv = skip_dash_dash(argv);
+# if ENABLE_HUSH_BASH_COMPAT
+ if (argv[0] && strcmp(argv[0], "-n") == 0) {
+ /* wait -n */
+ /* (bash accepts "wait -n PID" too and ignores PID) */
+ G.dead_job_exitcode = -1;
+ return wait_for_child_or_signal(NULL, -1 /*no job, wait for one job*/);
+ }
+# endif
+ if (argv[0] == NULL) {
+ /* Don't care about wait results */
+ /* Note 1: must wait until there are no more children */
+ /* Note 2: must be interruptible */
+ /* Examples:
+ * $ sleep 3 & sleep 6 & wait
+ * [1] 30934 sleep 3
+ * [2] 30935 sleep 6
+ * [1] Done sleep 3
+ * [2] Done sleep 6
+ * $ sleep 3 & sleep 6 & wait
+ * [1] 30936 sleep 3
+ * [2] 30937 sleep 6
+ * [1] Done sleep 3
+ * ^C <-- after ~4 sec from keyboard
+ * $
+ */
+ return wait_for_child_or_signal(NULL, 0 /*no job and no pid to wait for*/);
+ }
+
+ do {
+ pid_t pid = bb_strtou(*argv, NULL, 10);
+ if (errno || pid <= 0) {
+# if ENABLE_HUSH_JOB
+ if (argv[0][0] == '%') {
+ struct pipe *wait_pipe;
+ ret = 127; /* bash compat for bad jobspecs */
+ wait_pipe = parse_jobspec(*argv);
+ if (wait_pipe) {
+ ret = job_exited_or_stopped(wait_pipe);
+ if (ret < 0) {
+ ret = wait_for_child_or_signal(wait_pipe, 0);
+ } else {
+ /* waiting on "last dead job" removes it */
+ clean_up_last_dead_job();
+ }
+ }
+ /* else: parse_jobspec() already emitted error msg */
+ continue;
+ }
+# endif
+ /* mimic bash message */
+ bb_error_msg("wait: '%s': not a pid or valid job spec", *argv);
+ ret = EXIT_FAILURE;
+ continue; /* bash checks all argv[] */
+ }
+
+ /* Do we have such child? */
+ ret = waitpid(pid, &status, WNOHANG);
+ if (ret < 0) {
+ /* No */
+ ret = 127;
+ if (errno == ECHILD) {
+ if (pid == G.last_bg_pid) {
+ /* "wait $!" but last bg task has already exited. Try:
+ * (sleep 1; exit 3) & sleep 2; echo $?; wait $!; echo $?
+ * In bash it prints exitcode 0, then 3.
+ * In dash, it is 127.
+ */
+ ret = G.last_bg_pid_exitcode;
+ } else {
+ /* Example: "wait 1". mimic bash message */
+ bb_error_msg("wait: pid %u is not a child of this shell", (unsigned)pid);
+ }
+ } else {
+ /* ??? */
+ bb_perror_msg("wait %s", *argv);
+ }
+ continue; /* bash checks all argv[] */
+ }
+ if (ret == 0) {
+ /* Yes, and it still runs */
+ ret = wait_for_child_or_signal(NULL, pid);
+ } else {
+ /* Yes, and it just exited */
+ process_wait_result(NULL, pid, status);
+ ret = WEXITSTATUS(status);
+ if (WIFSIGNALED(status))
+ ret = 128 | WTERMSIG(status);
+ }
+ } while (*++argv);
+
+ return ret;
+}
+#endif
+
+#if ENABLE_HUSH_LOOPS || ENABLE_HUSH_FUNCTIONS
+static unsigned parse_numeric_argv1(char **argv, unsigned def, unsigned def_min)
+{
+ if (argv[1]) {
+ def = bb_strtou(argv[1], NULL, 10);
+ if (errno || def < def_min || argv[2]) {
+ bb_error_msg("%s: bad arguments", argv[0]);
+ def = UINT_MAX;
+ }
+ }
+ return def;
+}
+#endif
+
+#if ENABLE_HUSH_LOOPS
+static int FAST_FUNC builtin_break(char **argv)
+{
+ unsigned depth;
+ if (G.depth_of_loop == 0) {
+ bb_error_msg("%s: only meaningful in a loop", argv[0]);
+ /* if we came from builtin_continue(), need to undo "= 1" */
+ G.flag_break_continue = 0;
+ return EXIT_SUCCESS; /* bash compat */
+ }
+ G.flag_break_continue++; /* BC_BREAK = 1, or BC_CONTINUE = 2 */
+
+ G.depth_break_continue = depth = parse_numeric_argv1(argv, 1, 1);
+ if (depth == UINT_MAX)
+ G.flag_break_continue = BC_BREAK;
+ if (G.depth_of_loop < depth)
+ G.depth_break_continue = G.depth_of_loop;
+
+ return EXIT_SUCCESS;
+}
+
+static int FAST_FUNC builtin_continue(char **argv)
+{
+ G.flag_break_continue = 1; /* BC_CONTINUE = 2 = 1+1 */
+ return builtin_break(argv);
+}
+#endif
+
+#if ENABLE_HUSH_FUNCTIONS
+static int FAST_FUNC builtin_return(char **argv)
+{
+ int rc;
+
+ if (G_flag_return_in_progress != -1) {
+ bb_error_msg("%s: not in a function or sourced script", argv[0]);
+ return EXIT_FAILURE; /* bash compat */
+ }
+
+ G_flag_return_in_progress = 1;
+
+ /* bash:
+ * out of range: wraps around at 256, does not error out
+ * non-numeric param:
+ * f() { false; return qwe; }; f; echo $?
+ * bash: return: qwe: numeric argument required <== we do this
+ * 255 <== we also do this
+ */
+ rc = parse_numeric_argv1(argv, G.last_exitcode, 0);
+# if ENABLE_HUSH_TRAP
+ if (argv[1]) { /* "return ARG" inside a running trap sets $? */
+ debug_printf_exec("G.return_exitcode=%d\n", rc);
+ G.return_exitcode = rc;
+ }
+# endif
+ return rc;
+}
+#endif
+
+#if ENABLE_HUSH_TIMES
+static int FAST_FUNC builtin_times(char **argv UNUSED_PARAM)
+{
+ static const uint8_t times_tbl[] ALIGN1 = {
+ ' ', offsetof(struct tms, tms_utime),
+ '\n', offsetof(struct tms, tms_stime),
+ ' ', offsetof(struct tms, tms_cutime),
+ '\n', offsetof(struct tms, tms_cstime),
+ 0
+ };
+ const uint8_t *p;
+ unsigned clk_tck;
+ struct tms buf;
+
+ clk_tck = bb_clk_tck();
+
+ times(&buf);
+ p = times_tbl;
+ do {
+ unsigned sec, frac;
+ unsigned long t;
+ t = *(clock_t *)(((char *) &buf) + p[1]);
+ sec = t / clk_tck;
+ frac = t % clk_tck;
+ printf("%um%u.%03us%c",
+ sec / 60, sec % 60,
+ (frac * 1000) / clk_tck,
+ p[0]);
+ p += 2;
+ } while (*p);
+
+ return EXIT_SUCCESS;
+}
+#endif
+
+#if ENABLE_HUSH_MEMLEAK
+static int FAST_FUNC builtin_memleak(char **argv UNUSED_PARAM)
+{
+ void *p;
+ unsigned long l;
+
+# ifdef M_TRIM_THRESHOLD
+ /* Optional. Reduces probability of false positives */
+ malloc_trim(0);
+# endif
+ /* Crude attempt to find where "free memory" starts,
+ * sans fragmentation. */
+ p = malloc(240);
+ l = (unsigned long)p;
+ free(p);
+ p = malloc(3400);
+ if (l < (unsigned long)p) l = (unsigned long)p;
+ free(p);
+
+
+# if 0 /* debug */
+ {
+ struct mallinfo mi = mallinfo();
+ printf("top alloc:0x%lx malloced:%d+%d=%d\n", l,
+ mi.arena, mi.hblkhd, mi.arena + mi.hblkhd);
+ }
+# endif
+
+ if (!G.memleak_value)
+ G.memleak_value = l;
+
+ l -= G.memleak_value;
+ if ((long)l < 0)
+ l = 0;
+ l /= 1024;
+ if (l > 127)
+ l = 127;
+
+ /* Exitcode is "how many kilobytes we leaked since 1st call" */
+ return l;
+}
+#endif
--
2.34.1
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