strings: implement -t radix

v2: minor code cleanup, no changes.
v1: Implement -t radix option.
    Fix help text for -o option.

Signed-off-by: Tito Ragusa <farmatito@tiscali.it>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 23 insertions, 9 deletions

diff --git a/miscutils/strings.c b/miscutils/strings.c
index 9f5018244..ee6649625 100644
--- a/miscutils/strings.c
+++ b/miscutils/strings.c
@@ -8,13 +8,16 @@
  */
 
 //usage:#define strings_trivial_usage
-//usage:       "[-afo] [-n LEN] [FILE]..."
+//usage:       "[-fo] [-t o/d/x] [-n LEN] [FILE]..."
 //usage:#define strings_full_usage "\n\n"
 //usage:       "Display printable strings in a binary file\n"
-//usage:     "\n        -a      Scan whole file (default)"
-//usage:     "\n        -f      Precede strings with filenames"
-//usage:     "\n        -n LEN  At least LEN characters form a string (default 4)"
-//usage:     "\n        -o      Precede strings with decimal offsets"
+//We usually don't bother user with "nop" options. They work, but are not shown:
+////usage:     "\n      -a              Scan whole file (default)"
+//unimplemented alternative is -d: Only strings from initialized, loaded data sections
+//usage:     "\n        -f              Precede strings with filenames"
+//usage:     "\n        -o              Precede strings with octal offsets"
+//usage:     "\n        -t o/d/x        Precede strings with offsets in base 8/10/16"
+//usage:     "\n        -n LEN          At least LEN characters form a string (default 4)"
 
 #include "libbb.h"
 
@@ -22,6 +25,7 @@
 #define PRINT_NAME    2
 #define PRINT_OFFSET  4
 #define SIZE          8
+#define PRINT_RADIX  16
 
 int strings_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int strings_main(int argc UNUSED_PARAM, char **argv)
@@ -33,8 +37,11 @@ int strings_main(int argc UNUSED_PARAM, char **argv)
         char *string;
         const char *fmt = "%s: ";
         const char *n_arg = "4";
+        /* default for -o */
+        const char *radix = "o";
+        char *radix_fmt;
 
-        getopt32(argv, "afon:", &n_arg);
+        getopt32(argv, "afon:t:", &n_arg, &radix);
         /* -a is our default behaviour */
         /*argc -= optind;*/
         argv += optind;
@@ -43,6 +50,11 @@ int strings_main(int argc UNUSED_PARAM, char **argv)
         string = xzalloc(n + 1);
         n--;
 
+        if ((radix[0] != 'd' && radix[0] != 'o' && radix[0] != 'x') || radix[1] != 0)
+                bb_show_usage();
+
+        radix_fmt = xasprintf("%%7"OFF_FMT"%s ", radix);
+
         if (!*argv) {
                 fmt = "{%s}: ";
                 *--argv = (char *)bb_msg_standard_input;
@@ -67,8 +79,8 @@ int strings_main(int argc UNUSED_PARAM, char **argv)
                                                 if (option_mask32 & PRINT_NAME) {
                                                         printf(fmt, *argv);
                                                 }
-                                                if (option_mask32 & PRINT_OFFSET) {
-                                                        printf("%7"OFF_FMT"o ", offset - n);
+                                                if (option_mask32 & (PRINT_OFFSET | PRINT_RADIX)) {
+                                                        printf(radix_fmt, offset - n);
                                                 }
                                                 fputs(string, stdout);
                                         }
@@ -85,8 +97,10 @@ int strings_main(int argc UNUSED_PARAM, char **argv)
                 fclose_if_not_stdin(file);
         } while (*++argv);
 
-        if (ENABLE_FEATURE_CLEAN_UP)
+        if (ENABLE_FEATURE_CLEAN_UP) {
                 free(string);
+                free(radix_fmt);
+        }
 
         fflush_stdout_and_exit(status);
 }