comm: almost total rewrite; add testsuite
[oweals/busybox.git] / coreutils / readlink.c
1 /* vi: set sw=4 ts=4: */
2 /*
3  * Mini readlink implementation for busybox
4  *
5  * Copyright (C) 2000,2001 Matt Kraai <kraai@alumni.carnegiemellon.edu>
6  *
7  * Licensed under GPL v2 or later, see file LICENSE in this tarball for details.
8  */
9
10 #include "libbb.h"
11
12 int readlink_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
13 int readlink_main(int argc UNUSED_PARAM, char **argv)
14 {
15         char *buf;
16         char *fname;
17         char pathbuf[PATH_MAX];
18
19         USE_FEATURE_READLINK_FOLLOW(
20                 unsigned opt;
21                 /* We need exactly one non-option argument.  */
22                 opt_complementary = "=1";
23                 opt = getopt32(argv, "f");
24                 fname = argv[optind];
25         )
26         SKIP_FEATURE_READLINK_FOLLOW(
27                 const unsigned opt = 0;
28                 if (argc != 2) bb_show_usage();
29                 fname = argv[1];
30         )
31
32         /* compat: coreutils readlink reports errors silently via exit code */
33         logmode = LOGMODE_NONE;
34
35         if (opt) {
36                 buf = realpath(fname, pathbuf);
37         } else {
38                 buf = xmalloc_readlink_or_warn(fname);
39         }
40
41         if (!buf)
42                 return EXIT_FAILURE;
43         puts(buf);
44
45         if (ENABLE_FEATURE_CLEAN_UP && !opt)
46                 free(buf);
47
48         fflush_stdout_and_exit(EXIT_SUCCESS);
49 }