miscutils/strings.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * strings implementation for busybox
   4  *
   5  * Copyright Tito Ragusa <farmatito@tiscali.it>
   6  *
   7  * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
   8  */
   9
  10 #include "busybox.h"
  11 #include <stdio.h>
  12 #include <stdlib.h>
  13 #include <getopt.h>
  14 #include <ctype.h>
  15
  16 #define WHOLE_FILE              1
  17 #define PRINT_NAME              2
  18 #define PRINT_OFFSET    4
  19 #define SIZE                    8
  20
  21 int strings_main(int argc, char **argv);
  22 int strings_main(int argc, char **argv)
  23 {
  24         int n, c, i = 0, status = EXIT_SUCCESS;
  25         unsigned opt;
  26         unsigned long count;
  27         FILE *file = stdin;
  28         char *string;
  29         const char *fmt = "%s: ";
  30         const char *n_arg = "4";
  31
  32         opt = getopt32(argc, argv, "afon:", &n_arg);
  33         /* -a is our default behaviour */
  34
  35         argc -= optind;
  36         argv += optind;
  37
  38         n = xatoul_range(n_arg, 1, INT_MAX);
  39         string = xzalloc(n + 1);
  40         n--;
  41
  42         if (argc == 0) {
  43                 fmt = "{%s}: ";
  44                 *argv = (char *)bb_msg_standard_input;
  45                 goto PIPE;
  46         }
  47
  48         do {
  49                 file = fopen_or_warn(*argv, "r");
  50                 if (file) {
  51 PIPE:
  52                         count = 0;
  53                         do {
  54                                 c = fgetc(file);
  55                                 if (isprint(c) || c == '\t') {
  56                                         if (i <= n) {
  57                                                 string[i] = c;
  58                                         } else {
  59                                                 putchar(c);
  60                                         }
  61                                         if (i == n) {
  62                                                 if (opt & PRINT_NAME) {
  63                                                         printf(fmt, *argv);
  64                                                 }
  65                                                 if (opt & PRINT_OFFSET) {
  66                                                         printf("%7lo ", count - n);
  67                                                 }
  68                                                 printf("%s", string);
  69                                         }
  70                                         i++;
  71                                 } else {
  72                                         if (i > n) {
  73                                                 putchar('\n');
  74                                         }
  75                                         i = 0;
  76                                 }
  77                                 count++;
  78                         } while (c != EOF);
  79                         fclose_if_not_stdin(file);
  80                 } else {
  81                         status = EXIT_FAILURE;
  82                 }
  83         } while (--argc > 0);
  84
  85         if (ENABLE_FEATURE_CLEAN_UP)
  86                 free(string);
  87
  88         fflush_stdout_and_exit(status);
  89 }