src/group-list.c

   1 /* group-list.c --Print a list of group IDs or names.
   2    Copyright (C) 1989-2009 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation, either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Arnold Robbins.
  18    Major rewrite by David MacKenzie, djm@gnu.ai.mit.edu.
  19    Extracted from id.c by James Youngman. */
  20
  21 #include <config.h>
  22 #include <stdio.h>
  23 #include <sys/types.h>
  24 #include <pwd.h>
  25 #include <grp.h>
  26
  27 #include "system.h"
  28 #include "error.h"
  29 #include "mgetgroups.h"
  30 #include "quote.h"
  31 #include "group-list.h"
  32
  33
  34 /* Print all of the distinct groups the user is in. */
  35 extern bool
  36 print_group_list (const char *username,
  37                   uid_t ruid, gid_t rgid, gid_t egid,
  38                   bool use_names)
  39 {
  40   bool ok = true;
  41   struct passwd *pwd;
  42
  43   pwd = getpwuid (ruid);
  44   if (pwd == NULL)
  45     ok = false;
  46
  47   if (!print_group (rgid, use_names))
  48     ok = false;
  49
  50   if (egid != rgid)
  51     {
  52       putchar (' ');
  53       if (!print_group (egid, use_names))
  54         ok = false;
  55     }
  56
  57 #if HAVE_GETGROUPS
  58   {
  59     GETGROUPS_T *groups;
  60     int i;
  61
  62     int n_groups = mgetgroups (username, (pwd ? pwd->pw_gid : (gid_t) -1),
  63                                &groups);
  64     if (n_groups < 0)
  65       {
  66         if (username)
  67           {
  68             error (0, errno, _("failed to get groups for user %s"),
  69                    quote (username));
  70           }
  71         else
  72           {
  73             error (0, errno, _("failed to get groups for the current process"));
  74           }
  75         return false;
  76       }
  77
  78     for (i = 0; i < n_groups; i++)
  79       if (groups[i] != rgid && groups[i] != egid)
  80         {
  81           putchar (' ');
  82           if (!print_group (groups[i], use_names))
  83             ok = false;
  84         }
  85     free (groups);
  86   }
  87 #endif /* HAVE_GETGROUPS */
  88   return ok;
  89 }
  90
  91
  92 /* Print the name or value of group ID GID. */
  93 extern bool
  94 print_group (gid_t gid, bool use_name)
  95 {
  96   struct group *grp = NULL;
  97   bool ok = true;
  98
  99   if (use_name)
 100     {
 101       grp = getgrgid (gid);
 102       if (grp == NULL)
 103         {
 104           error (0, 0, _("cannot find name for group ID %lu"),
 105                  (unsigned long int) gid);
 106           ok = false;
 107         }
 108     }
 109
 110   if (grp == NULL)
 111     printf ("%lu", (unsigned long int) gid);
 112   else
 113     printf ("%s", grp->gr_name);
 114   return ok;
 115 }