miscutils/strings.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * strings implementation for busybox
   4  *
   5  * Copyright 2003 Tito Ragusa <farmatito@tiscali.it>
   6  *
   7  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   8  */
   9
  10 //usage:#define strings_trivial_usage
  11 //usage:       "[-afo] [-n LEN] [FILE]..."
  12 //usage:#define strings_full_usage "\n\n"
  13 //usage:       "Display printable strings in a binary file\n"
  14 //usage:     "\nOptions:"
  15 //usage:     "\n        -a      Scan whole file (default)"
  16 //usage:     "\n        -f      Precede strings with filenames"
  17 //usage:     "\n        -n LEN  At least LEN characters form a string (default 4)"
  18 //usage:     "\n        -o      Precede strings with decimal offsets"
  19
  20 #include "libbb.h"
  21
  22 #define WHOLE_FILE    1
  23 #define PRINT_NAME    2
  24 #define PRINT_OFFSET  4
  25 #define SIZE          8
  26
  27 int strings_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  28 int strings_main(int argc UNUSED_PARAM, char **argv)
  29 {
  30         int n, c, status = EXIT_SUCCESS;
  31         unsigned count;
  32         off_t offset;
  33         FILE *file;
  34         char *string;
  35         const char *fmt = "%s: ";
  36         const char *n_arg = "4";
  37
  38         getopt32(argv, "afon:", &n_arg);
  39         /* -a is our default behaviour */
  40         /*argc -= optind;*/
  41         argv += optind;
  42
  43         n = xatou_range(n_arg, 1, INT_MAX);
  44         string = xzalloc(n + 1);
  45         n--;
  46
  47         if (!*argv) {
  48                 fmt = "{%s}: ";
  49                 *--argv = (char *)bb_msg_standard_input;
  50         }
  51
  52         do {
  53                 file = fopen_or_warn_stdin(*argv);
  54                 if (!file) {
  55                         status = EXIT_FAILURE;
  56                         continue;
  57                 }
  58                 offset = 0;
  59                 count = 0;
  60                 do {
  61                         c = fgetc(file);
  62                         if (isprint_asciionly(c) || c == '\t') {
  63                                 if (count > n) {
  64                                         bb_putchar(c);
  65                                 } else {
  66                                         string[count] = c;
  67                                         if (count == n) {
  68                                                 if (option_mask32 & PRINT_NAME) {
  69                                                         printf(fmt, *argv);
  70                                                 }
  71                                                 if (option_mask32 & PRINT_OFFSET) {
  72                                                         printf("%7"OFF_FMT"o ", offset - n);
  73                                                 }
  74                                                 fputs(string, stdout);
  75                                         }
  76                                         count++;
  77                                 }
  78                         } else {
  79                                 if (count > n) {
  80                                         bb_putchar('\n');
  81                                 }
  82                                 count = 0;
  83                         }
  84                         offset++;
  85                 } while (c != EOF);
  86                 fclose_if_not_stdin(file);
  87         } while (*++argv);
  88
  89         if (ENABLE_FEATURE_CLEAN_UP)
  90                 free(string);
  91
  92         fflush_stdout_and_exit(status);
  93 }