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 {
  23         int n, c, i = 0, status = EXIT_SUCCESS;
  24         unsigned opt;
  25         unsigned long count;
  26         FILE *file = stdin;
  27         char *string;
  28         const char *fmt = "%s: ";
  29         char *n_arg = "4";
  30
  31         opt = getopt32(argc, argv, "afon:", &n_arg);
  32         /* -a is our default behaviour */
  33
  34         argc -= optind;
  35         argv += optind;
  36
  37         n = xatoul_range(n_arg, 1, INT_MAX);
  38         string = xzalloc(n + 1);
  39         n--;
  40
  41         if (argc == 0) {
  42                 fmt = "{%s}: ";
  43                 *argv = (char *)bb_msg_standard_input;
  44                 goto PIPE;
  45         }
  46
  47         do {
  48                 file = fopen_or_warn(*argv, "r");
  49                 if (file) {
  50 PIPE:
  51                         count = 0;
  52                         do {
  53                                 c = fgetc(file);
  54                                 if (isprint(c) || c == '\t') {
  55                                         if (i <= n) {
  56                                                 string[i] = c;
  57                                         } else {
  58                                                 putchar(c);
  59                                         }
  60                                         if (i == n) {
  61                                                 if (opt & PRINT_NAME) {
  62                                                         printf(fmt, *argv);
  63                                                 }
  64                                                 if (opt & PRINT_OFFSET) {
  65                                                         printf("%7lo ", count - n);
  66                                                 }
  67                                                 printf("%s", string);
  68                                         }
  69                                         i++;
  70                                 } else {
  71                                         if (i > n) {
  72                                                 putchar('\n');
  73                                         }
  74                                         i = 0;
  75                                 }
  76                                 count++;
  77                         } while (c != EOF);
  78                         fclose_if_not_stdin(file);
  79                 } else {
  80                         status = EXIT_FAILURE;
  81                 }
  82         } while (--argc > 0);
  83
  84         if (ENABLE_FEATURE_CLEAN_UP)
  85                 free(string);
  86
  87         fflush_stdout_and_exit(status);
  88 }