debianutils/which.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Which implementation for busybox
   4  *
   5  * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
   6  * Copyright (C) 2006 Gabriel Somlo <somlo at cmu.edu>
   7  *
   8  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   9  *
  10  * Based on which from debianutils
  11  */
  12
  13 //usage:#define which_trivial_usage
  14 //usage:       "[COMMAND]..."
  15 //usage:#define which_full_usage "\n\n"
  16 //usage:       "Locate a COMMAND"
  17 //usage:
  18 //usage:#define which_example_usage
  19 //usage:       "$ which login\n"
  20 //usage:       "/bin/login\n"
  21
  22 #include "libbb.h"
  23
  24 int which_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  25 int which_main(int argc UNUSED_PARAM, char **argv)
  26 {
  27         IF_DESKTOP(int opt;)
  28         int status = EXIT_SUCCESS;
  29         char *path;
  30         char *p;
  31
  32         opt_complementary = "-1"; /* at least one argument */
  33         IF_DESKTOP(opt =) getopt32(argv, "a");
  34         argv += optind;
  35
  36         /* This matches what is seen on e.g. ubuntu.
  37          * "which" there is a shell script. */
  38         path = getenv("PATH");
  39         if (!path) {
  40                 path = (char*)bb_PATH_root_path;
  41                 putenv(path);
  42                 path += 5; /* skip "PATH=" */
  43         }
  44
  45         do {
  46 #if ENABLE_DESKTOP
  47 /* Much bloat just to support -a */
  48                 if (strchr(*argv, '/')) {
  49                         if (execable_file(*argv)) {
  50                                 puts(*argv);
  51                                 continue;
  52                         }
  53                         status = EXIT_FAILURE;
  54                 } else {
  55                         char *path2 = xstrdup(path);
  56                         char *tmp = path2;
  57
  58                         p = find_execable(*argv, &tmp);
  59                         if (!p)
  60                                 status = EXIT_FAILURE;
  61                         else {
  62  print:
  63                                 puts(p);
  64                                 free(p);
  65                                 if (opt) {
  66                                         /* -a: show matches in all PATH components */
  67                                         if (tmp) {
  68                                                 p = find_execable(*argv, &tmp);
  69                                                 if (p)
  70                                                         goto print;
  71                                         }
  72                                 }
  73                         }
  74                         free(path2);
  75                 }
  76 #else
  77 /* Just ignoring -a */
  78                 if (strchr(*argv, '/')) {
  79                         if (execable_file(*argv)) {
  80                                 puts(*argv);
  81                                 continue;
  82                         }
  83                 } else {
  84                         char *path2 = xstrdup(path);
  85                         char *tmp = path2;
  86                         p = find_execable(*argv, &tmp);
  87                         free(path2);
  88                         if (p) {
  89                                 puts(p);
  90                                 free(p);
  91                                 continue;
  92                         }
  93                 }
  94                 status = EXIT_FAILURE;
  95 #endif
  96         } while (*(++argv) != NULL);
  97
  98         fflush_stdout_and_exit(status);
  99 }