1/*strings.c - print the strings of printable characters in files.
2 *
3 * Copyright 2014 Kyung-su Kim <kaspyx@gmail.com>
4 * Copyright 2014 Kyungwan Han <asura321@gmail.com>
5 *
6 * No Standard
7 * TODO: utf8 strings
8 * TODO: posix -t
9
10USE_STRINGS(NEWTOY(strings, "an#=4<1fo", TOYFLAG_USR|TOYFLAG_BIN))
11
12config STRINGS
13  bool "strings"
14  default y
15  help
16    usage: strings [-fo] [-n LEN] [FILE...]
17
18    Display printable strings in a binary file
19
20    -f	Precede strings with filenames
21    -n	At least LEN characters form a string (default 4)
22    -o	Precede strings with decimal offsets
23*/
24
25#define FOR_strings
26#include "toys.h"
27
28GLOBALS(
29  long num;
30)
31
32void do_strings(int fd, char *filename)
33{
34  int nread, i, wlen = TT.num, count = 0;
35  off_t offset = 0;
36  char *string = xzalloc(wlen + 1);
37
38  for (;;) {
39    nread = read(fd, toybuf, sizeof(toybuf));
40    if (nread < 0) perror_msg("%s", filename);
41    if (nread < 1) break;
42    for (i = 0; i < nread; i++, offset++) {
43      if (((toybuf[i] >= 32) && (toybuf[i] <= 126)) || (toybuf[i] == '\t')) {
44        if (count == wlen) fputc(toybuf[i], stdout);
45        else {
46          string[count++] = toybuf[i];
47          if (count == wlen) {
48            if (toys.optflags & FLAG_f) printf("%s: ", filename);
49            if (toys.optflags & FLAG_o)
50              printf("%7lld ",(long long)(offset - wlen));
51            printf("%s", string);
52          }
53        }
54      } else {
55        if (count == wlen) xputc('\n');
56        count = 0;
57      }
58    }
59  }
60  xclose(fd);
61  free(string);
62}
63
64void strings_main(void)
65{
66  loopfiles(toys.optargs, do_strings);
67}
68