[PATCH 5/5] cmd: printf: forward '%p' format string specifier

[lukas.funke-oss at weidmueller.com]

From: Lukas Funke <lukas.funke at weidmueller.com>

Forward '%p' format specifier to the underlying format logic in order
to print pointers, especially bitmaps.

Signed-off-by: Lukas Funke <lukas.funke at weidmueller.com>
---

 cmd/printf.c | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/cmd/printf.c b/cmd/printf.c
index 0c6887e0d6..a90c923871 100644
--- a/cmd/printf.c
+++ b/cmd/printf.c
@@ -90,6 +90,7 @@
 #include <stddef.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <linux/bitmap.h>
 
 #define WANT_HEX_ESCAPES 0
 #define PRINT_CONVERSION_ERROR 1
@@ -476,6 +477,16 @@ static int get_width_prec(const char *str)
 	return (int)v;
 }
 
+static int print_pointer(struct print_inf *inf, char *format,
+			 unsigned int fmt_length, const char *argument)
+{
+	u64 value = simple_strtoull(argument, NULL, 0);
+
+	printf_str(inf, format, &value);
+
+	return inf->error;
+}
+
 /* Print the text in FORMAT, using ARGV for arguments to any '%' directives.
  * Return advanced ARGV.
  */
@@ -536,6 +547,24 @@ static char **print_formatted(struct print_inf *inf, char *f, char **argv, int *
 					}
 				}
 			}
+			if (*f == 'p') {
+				static const char ptr_format_chars[] = "bl";
+				++f;
+				++direc_length;
+				char *p = strchr(ptr_format_chars, *f);
+				/* consume whole format token */
+				while (*f != '\0' && *(p++) == *f) {
+					++f;
+					++direc_length;
+				}
+				if (print_pointer(inf, direc_start, direc_length, *argv++)) {
+					printf("`%s': invalid format\n", direc_start);
+					/* causes main() to exit with error */
+					return saved_argv - 1;
+				}
+				f--;
+				break;
+			}
 
 			/* Remove "lLhz" size modifiers, repeatedly.
 			 * bash does not like "%lld", but coreutils
-- 
2.30.2