debianutils/which.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Which implementation for busybox
   4  *
   5  * Copyright (C) 1999-2003 by Erik Andersen <andersen@codepoet.org>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  20  *
  21  */
  22
  23 /* getopt not needed */
  24 #include <string.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include "busybox.h"
  28
  29 static int file_exists(char *file)
  30 {
  31         struct stat filestat;
  32
  33         if (stat(file, &filestat) == 0 &&
  34                         S_ISREG(filestat.st_mode) &&
  35                         filestat.st_mode & S_IXUSR)
  36                 return 1;
  37         else
  38                 return 0;
  39 }
  40
  41 extern int which_main(int argc, char **argv)
  42 {
  43         char *path_list, *path_n;
  44         int i, count=1, found, status = EXIT_SUCCESS;
  45
  46         if (argc <= 1 || **(argv + 1) == '-')
  47                 bb_show_usage();
  48         argc--;
  49
  50         path_list = getenv("PATH");
  51         if (path_list != NULL) {
  52                 for(i=strlen(path_list); i > 0; i--)
  53                         if (path_list[i]==':') {
  54                                 path_list[i]=0;
  55                                 count++;
  56                         }
  57         } else {
  58                 path_list = "/bin\0/sbin\0/usr/bin\0/usr/sbin\0/usr/local/bin";
  59                 count = 5;
  60         }
  61
  62         while(argc-- > 0) {
  63                 char *buf;
  64                 path_n = path_list;
  65                 argv++;
  66                 found = 0;
  67
  68                 /*
  69                  * Check if we were given the full path, first.
  70                  * Otherwise see if the file exists in our $PATH.
  71                  */
  72                 buf = *argv;
  73                 if (file_exists(buf)) {
  74                         puts(buf);
  75                         found = 1;
  76                 } else {
  77                         for (i = 0; i < count; i++) {
  78                                 buf = concat_path_file(path_n, *argv);
  79                                 if (file_exists(buf)) {
  80                                         puts(buf);
  81                                         found = 1;
  82                                         break;
  83                                 }
  84                                 free(buf);
  85                                 path_n += (strlen(path_n) + 1);
  86                         }
  87                 }
  88                 if (!found)
  89                         status = EXIT_FAILURE;
  90         }
  91         return status;
  92 }
  93
  94 /*
  95 Local Variables:
  96 c-file-style: "linux"
  97 c-basic-offset: 4
  98 tab-width: 4
  99 End:
 100 */