debianutils/which.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
   4  * Copyright (C) 2006 Gabriel Somlo <somlo at cmu.edu>
   5  *
   6  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   7  */
   8 //config:config WHICH
   9 //config:       bool "which (3.7 kb)"
  10 //config:       default y
  11 //config:       help
  12 //config:       which is used to find programs in your PATH and
  13 //config:       print out their pathnames.
  14
  15 //applet:IF_WHICH(APPLET(which, BB_DIR_USR_BIN, BB_SUID_DROP))
  16
  17 //kbuild:lib-$(CONFIG_WHICH) += which.o
  18
  19 //usage:#define which_trivial_usage
  20 //usage:       "[COMMAND]..."
  21 //usage:#define which_full_usage "\n\n"
  22 //usage:       "Locate a COMMAND"
  23 //usage:
  24 //usage:#define which_example_usage
  25 //usage:       "$ which login\n"
  26 //usage:       "/bin/login\n"
  27
  28 #include "libbb.h"
  29
  30 int which_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  31 int which_main(int argc UNUSED_PARAM, char **argv)
  32 {
  33         const char *env_path;
  34         int status = 0;
  35
  36         env_path = getenv("PATH");
  37         if (!env_path)
  38                 env_path = bb_default_root_path;
  39
  40         opt_complementary = "-1"; /* at least one argument */
  41         getopt32(argv, "a");
  42         argv += optind;
  43
  44         do {
  45                 int missing = 1;
  46
  47                 /* If file contains a slash don't use PATH */
  48                 if (strchr(*argv, '/')) {
  49                         if (file_is_executable(*argv)) {
  50                                 missing = 0;
  51                                 puts(*argv);
  52                         }
  53                 } else {
  54                         char *path;
  55                         char *tmp;
  56                         char *p;
  57
  58                         path = tmp = xstrdup(env_path);
  59                         while ((p = find_executable(*argv, &tmp)) != NULL) {
  60                                 missing = 0;
  61                                 puts(p);
  62                                 free(p);
  63                                 if (!option_mask32) /* -a not set */
  64                                         break;
  65                         }
  66                         free(path);
  67                 }
  68                 status |= missing;
  69         } while (*++argv);
  70
  71         return status;
  72 }