Mercurial > hg > octave-nkf > gnulib-hg
annotate lib/group-member.c @ 4542:4436daed2dbd
Include "xalloc.h".
(xmalloc, xrealloc): Remove decls.
(get_group_info): Remove casts no longer required in C89.
| author | Paul Eggert <eggert@cs.ucla.edu> |
|---|---|
| date | Thu, 14 Aug 2003 22:56:12 +0000 |
| parents | 807294ed0f4f |
| children | fa597018cd8b |
| rev | line source |
|---|---|
| 785 | 1 /* group-member.c -- determine whether group id is in calling user's group list |
| 4542 | 2 Copyright (C) 1994, 1997, 1998, 2003 Free Software Foundation, Inc. |
| 785 | 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 2, or (at your option) | |
| 7 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, write to the Free Software Foundation, | |
| 16 Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ | |
| 17 | |
|
1278
9ad625a30b7d
Use #if, not #ifdef with HAVE_ macros
Jim Meyering <jim@meyering.net>
parents:
1188
diff
changeset
|
18 #if HAVE_CONFIG_H |
| 785 | 19 # include <config.h> |
| 20 #endif | |
| 21 | |
| 22 #include <stdio.h> | |
| 23 #include <sys/types.h> | |
| 24 | |
| 25 #ifdef STDC_HEADERS | |
| 26 # include <stdlib.h> | |
| 27 #endif | |
| 28 | |
|
1278
9ad625a30b7d
Use #if, not #ifdef with HAVE_ macros
Jim Meyering <jim@meyering.net>
parents:
1188
diff
changeset
|
29 #if HAVE_UNISTD_H |
| 785 | 30 # include <unistd.h> |
| 31 #endif | |
| 32 | |
| 33 #include "group-member.h" | |
| 4542 | 34 #include "xalloc.h" |
| 785 | 35 |
| 36 struct group_info | |
| 37 { | |
| 38 int n_groups; | |
| 39 GETGROUPS_T *group; | |
| 40 }; | |
| 41 | |
|
1278
9ad625a30b7d
Use #if, not #ifdef with HAVE_ macros
Jim Meyering <jim@meyering.net>
parents:
1188
diff
changeset
|
42 #if HAVE_GETGROUPS |
| 785 | 43 |
| 44 static void | |
| 1188 | 45 free_group_info (struct group_info *g) |
| 785 | 46 { |
| 47 free (g->group); | |
| 48 free (g); | |
| 49 } | |
| 50 | |
| 51 static struct group_info * | |
| 1188 | 52 get_group_info (void) |
| 785 | 53 { |
| 54 int n_groups; | |
| 55 int n_group_slots; | |
| 56 struct group_info *gi; | |
| 57 GETGROUPS_T *group; | |
| 58 | |
| 59 /* getgroups () returns the number of elements that it was able to | |
| 60 place into the array. We simply continue to call getgroups () | |
| 61 until the number of elements placed into the array is smaller than | |
| 62 the physical size of the array. */ | |
| 63 | |
| 64 group = NULL; | |
| 65 n_groups = 0; | |
| 66 n_group_slots = 0; | |
| 67 while (n_groups == n_group_slots) | |
| 68 { | |
| 69 n_group_slots += 64; | |
| 4542 | 70 group = xrealloc (group, n_group_slots * sizeof (GETGROUPS_T)); |
| 785 | 71 n_groups = getgroups (n_group_slots, group); |
| 72 } | |
| 73 | |
| 74 /* In case of error, the user loses. */ | |
| 75 if (n_groups < 0) | |
| 76 { | |
| 77 free (group); | |
| 78 return NULL; | |
| 79 } | |
| 80 | |
| 4542 | 81 gi = xmalloc (sizeof (*gi)); |
| 785 | 82 gi->n_groups = n_groups; |
| 83 gi->group = group; | |
| 84 | |
| 85 return gi; | |
| 86 } | |
| 87 | |
| 88 #endif /* not HAVE_GETGROUPS */ | |
| 89 | |
| 90 /* Return non-zero if GID is one that we have in our groups list. | |
| 91 If there is no getgroups function, return non-zero if GID matches | |
| 92 either of the current or effective group IDs. */ | |
| 93 | |
| 94 int | |
| 1188 | 95 group_member (gid_t gid) |
| 785 | 96 { |
| 97 #ifndef HAVE_GETGROUPS | |
| 98 return ((gid == getgid ()) || (gid == getegid ())); | |
| 99 #else | |
| 100 int i; | |
| 101 int found; | |
| 102 struct group_info *gi; | |
| 103 | |
| 104 gi = get_group_info (); | |
| 105 if (gi == NULL) | |
| 106 return 0; | |
| 107 | |
| 108 /* Search through the list looking for GID. */ | |
| 109 found = 0; | |
| 110 for (i = 0; i < gi->n_groups; i++) | |
| 111 { | |
| 112 if (gid == gi->group[i]) | |
| 113 { | |
| 114 found = 1; | |
| 115 break; | |
| 116 } | |
| 117 } | |
| 790 | 118 |
| 785 | 119 free_group_info (gi); |
| 120 | |
| 121 return found; | |
| 122 #endif /* HAVE_GETGROUPS */ | |
| 123 } | |
| 124 | |
| 125 #ifdef TEST | |
| 126 | |
| 127 char *program_name; | |
| 128 | |
| 129 int | |
| 130 main (int argc, char** argv) | |
| 131 { | |
| 132 int i; | |
| 133 | |
| 134 program_name = argv[0]; | |
| 135 | |
| 136 for (i=1; i<argc; i++) | |
| 137 { | |
| 138 gid_t gid; | |
| 139 | |
| 140 gid = atoi (argv[i]); | |
| 141 printf ("%d: %s\n", gid, group_member (gid) ? "yes" : "no"); | |
| 142 } | |
| 143 exit (0); | |
| 144 } | |
| 145 | |
| 146 #endif /* TEST */ |