kc3-lang/gnulib/lib/group-member.c

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• Hash : fae7fdcf
  Author :
  Date : 2011-05-12T02:03:07
  

  group-member: Declare function in <unistd.h>.
  
  * lib/unistd.in.h (group_member): New declaration.
  * lib/group-member.h: Remove file.
  * lib/group-member.c: Include <unistd.h> instead of group-member.h.
  * tests/test-unistd-c++.cc: Check signature of group_member.
  * m4/group-member.m4 (gl_FUNC_GROUP_MEMBER): Require
  gl_UNISTD_H_DEFAULTS. Set HAVE_GROUP_MEMBER.
  * m4/unistd_h.m4 (gl_UNISTD_H): Check whether group_member is declared.
  (gl_UNISTD_H_DEFAULTS): Initialize GNULIB_GROUP_MEMBER,
  HAVE_GROUP_MEMBER.
  * modules/group-member (Files): Remove lib/group-member.h.
  (Depends-on): Add unistd. Specify conditions.
  (configure.ac): Invoke gl_UNISTD_MODULE_INDICATOR.
  (Include): Change to <unistd.h>.
  * modules/unistd (Makefile.am): Substitute GNULIB_GROUP_MEMBER,
  HAVE_GROUP_MEMBER.
  * NEWS: Mention the change.
  * lib/euidaccess.c: Don't include group-member.h.
  

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• lib/group-member.c

• /* group-member.c -- determine whether group id is in calling user's group list
  
     Copyright (C) 1994, 1997-1998, 2003, 2005-2006, 2009-2011 Free Software
     Foundation, Inc.
  
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
     the Free Software Foundation; either version 3 of the License, or
     (at your option) any later version.
  
     This program is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     GNU General Public License for more details.
  
     You should have received a copy of the GNU General Public License
     along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  
  #include <config.h>
  
  /* Specification.  */
  #include <unistd.h>
  
  #include <stdbool.h>
  #include <stdio.h>
  #include <sys/types.h>
  #include <stdlib.h>
  
  #include "xalloc.h"
  
  struct group_info
    {
      int n_groups;
      gid_t *group;
    };
  
  static void
  free_group_info (struct group_info const *g)
  {
    free (g->group);
  }
  
  static bool
  get_group_info (struct group_info *gi)
  {
    int n_groups;
    int n_group_slots = getgroups (0, NULL);
    gid_t *group;
  
    if (n_group_slots < 0)
      return false;
  
    /* Avoid xnmalloc, as it goes awry when SIZE_MAX < n_group_slots.  */
    if (xalloc_oversized (n_group_slots, sizeof *group))
      xalloc_die ();
    group = xmalloc (n_group_slots * sizeof *group);
    n_groups = getgroups (n_group_slots, group);
  
    /* In case of error, the user loses. */
    if (n_groups < 0)
      {
        free (group);
        return false;
      }
  
    gi->n_groups = n_groups;
    gi->group = group;
  
    return true;
  }
  
  /* Return non-zero if GID is one that we have in our groups list.
     Note that the groups list is not guaranteed to contain the current
     or effective group ID, so they should generally be checked
     separately.  */
  
  int
  group_member (gid_t gid)
  {
    int i;
    int found;
    struct group_info gi;
  
    if (! get_group_info (&gi))
      return 0;
  
    /* Search through the list looking for GID. */
    found = 0;
    for (i = 0; i < gi.n_groups; i++)
      {
        if (gid == gi.group[i])
          {
            found = 1;
            break;
          }
      }
  
    free_group_info (&gi);
  
    return found;
  }
  
  #ifdef TEST
  
  char *program_name;
  
  int
  main (int argc, char **argv)
  {
    int i;
  
    program_name = argv[0];
  
    for (i = 1; i < argc; i++)
      {
        gid_t gid;
  
        gid = atoi (argv[i]);
        printf ("%d: %s\n", gid, group_member (gid) ? "yes" : "no");
      }
    exit (0);
  }
  
  #endif /* TEST */
  

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