[PATCH v2] cmd: Add pause command

[Samuel Dionne-Riel]

This command is being introduced with the goal of allowing user-friendly
"generic use case" U-Boot builds to pause until user input under some
situations.

The main use case would be when a boot failure happens, to pause until
the user has had time to acknowledge the current state.

Tested with sandbox using:

    make && ./u-boot -v -T -c 'ut lib lib_test_hush_pause'

Signed-off-by: Samuel Dionne-Riel <samuel at dionne-riel.com>
---
 cmd/Kconfig                 |  7 +++++
 cmd/Makefile                |  1 +
 cmd/pause.c                 | 35 +++++++++++++++++++++
 configs/sandbox64_defconfig |  1 +
 configs/sandbox_defconfig   |  1 +
 test/cmd/Makefile           |  3 ++
 test/cmd/test_pause.c       | 62 +++++++++++++++++++++++++++++++++++++
 7 files changed, 110 insertions(+)
 create mode 100644 cmd/pause.c
 create mode 100644 test/cmd/test_pause.c

diff --git a/cmd/Kconfig b/cmd/Kconfig
index 3625ff2a50b..e774670a35c 100644
--- a/cmd/Kconfig
+++ b/cmd/Kconfig
@@ -1961,6 +1961,13 @@ config CMD_GETTIME
 	  milliseconds. See also the 'bootstage' command which
provides more flexibility for boot timing.
 
+config CMD_PAUSE
+	bool "pause command"
+	default n
+	help
+	  Delay execution waiting for any user input.
+	  Useful to allow the user to read a failure log.
+
 config CMD_RNG
 	bool "rng command"
 	depends on DM_RNG
diff --git a/cmd/Makefile b/cmd/Makefile
index 5e43a1e022e..98a6224bdc1 100644
--- a/cmd/Makefile
+++ b/cmd/Makefile
@@ -102,6 +102,7 @@ obj-$(CONFIG_CMD_MFSL) += mfsl.o
 obj-$(CONFIG_CMD_MII) += mii.o
 obj-$(CONFIG_CMD_MISC) += misc.o
 obj-$(CONFIG_CMD_MDIO) += mdio.o
+obj-$(CONFIG_CMD_PAUSE) += pause.o
 obj-$(CONFIG_CMD_SLEEP) += sleep.o
 obj-$(CONFIG_CMD_MMC) += mmc.o
 obj-$(CONFIG_CMD_OPTEE_RPMB) += optee_rpmb.o
diff --git a/cmd/pause.c b/cmd/pause.c
new file mode 100644
index 00000000000..07bf346f3d1
--- /dev/null
+++ b/cmd/pause.c
@@ -0,0 +1,35 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2021
+ * Samuel Dionne-Riel <samuel at dionne-riel.com>
+ */
+
+#include <command.h>
+#include <stdio.h>
+
+static int do_pause(struct cmd_tbl *cmdtp, int flag, int argc, char
*const argv[]) +{
+	char *message = "Press any key to continue...";
+
+	if (argc > 2)
+		return CMD_RET_USAGE;
+
+	if (argc == 2)
+		message = argv[1];
+
+	/* No newline, so it sticks to the bottom of the screen */
+	printf("%s", message);
+
+	/* Wait on "any" key... */
+	(void) getchar();
+
+	/* Since there was no newline, we need it now. */
+	printf("\n");
+
+	return CMD_RET_SUCCESS;
+}
+
+U_BOOT_CMD(pause, 2, 1, do_pause,
+	"delay until user input",
+	"pause [prompt] - Wait until users presses any key. [prompt]
can be used to customize the message.\n" +);
diff --git a/configs/sandbox64_defconfig b/configs/sandbox64_defconfig
index 6553568e768..0af582d642d 100644
--- a/configs/sandbox64_defconfig
+++ b/configs/sandbox64_defconfig
@@ -67,6 +67,7 @@ CONFIG_CMD_BMP=y
 CONFIG_CMD_EFIDEBUG=y
 CONFIG_CMD_RTC=y
 CONFIG_CMD_TIME=y
+CONFIG_CMD_PAUSE=y
 CONFIG_CMD_TIMER=y
 CONFIG_CMD_SOUND=y
 CONFIG_CMD_QFW=y
diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig
index eba7bcbb483..d856d9b0942 100644
--- a/configs/sandbox_defconfig
+++ b/configs/sandbox_defconfig
@@ -96,6 +96,7 @@ CONFIG_CMD_BOOTCOUNT=y
 CONFIG_CMD_EFIDEBUG=y
 CONFIG_CMD_RTC=y
 CONFIG_CMD_TIME=y
+CONFIG_CMD_PAUSE=y
 CONFIG_CMD_TIMER=y
 CONFIG_CMD_SOUND=y
 CONFIG_CMD_QFW=y
diff --git a/test/cmd/Makefile b/test/cmd/Makefile
index c331757425e..1bb02d93a23 100644
--- a/test/cmd/Makefile
+++ b/test/cmd/Makefile
@@ -5,6 +5,9 @@
 ifdef CONFIG_HUSH_PARSER
 obj-$(CONFIG_CONSOLE_RECORD) += test_echo.o
 endif
+ifdef CONFIG_CONSOLE_RECORD
+obj-$(CONFIG_CMD_PAUSE) += test_pause.o
+endif
 obj-y += mem.o
 obj-$(CONFIG_CMD_ADDRMAP) += addrmap.o
 obj-$(CONFIG_CMD_FDT) += fdt.o
diff --git a/test/cmd/test_pause.c b/test/cmd/test_pause.c
new file mode 100644
index 00000000000..9c55c6302bc
--- /dev/null
+++ b/test/cmd/test_pause.c
@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Tests for pause command
+ *
+ * Copyright 2022, Samuel Dionne-Riel <samuel at dionne-riel.com>
+ *
+ * Based on tests for echo:
+ * Copyright 2020, Heinrich Schuchadt <xypron.glpk at gmx.de>
+ */
+
+#include <common.h>
+#include <command.h>
+#include <asm/global_data.h>
+#include <display_options.h>
+#include <test/lib.h>
+#include <test/test.h>
+#include <test/ut.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct test_data {
+	char *cmd;
+	char *expected;
+	int expected_ret;
+};
+
+static struct test_data pause_data[] = {
+	/* Test default message */
+	{"pause",
+	 "Press any key to continue...",
+	 0},
+	/* Test provided message */
+	{"pause 'Prompt for pause...'",
+	 "Prompt for pause...",
+	 0},
+	/* Test providing more than one params */
+	{"pause a b",
+	 "pause - delay until user input", /* start of help message */
+	 1},
+};
+
+static int lib_test_hush_pause(struct unit_test_state *uts)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(pause_data); ++i) {
+		ut_silence_console(uts);
+		console_record_reset_enable();
+		/* Only cook a newline when the command is expected to
pause. */
+		if (pause_data[i].expected_ret == 0)
+			console_in_puts("\n");
+		ut_asserteq(pause_data[i].expected_ret,
run_command(pause_data[i].cmd, 0));
+		ut_unsilence_console(uts);
+		console_record_readline(uts->actual_str,
+					sizeof(uts->actual_str));
+		ut_asserteq_str(pause_data[i].expected,
uts->actual_str);
+		ut_asserteq(pause_data[i].expected_ret,
ut_check_console_end(uts));
+	}
+	return 0;
+}
+
+LIB_TEST(lib_test_hush_pause, 0);
-- 
2.35.1


-- 
Samuel Dionne-Riel