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m---------gnulib0
-rw-r--r--gnulib/lib/group-member.c124
2 files changed, 124 insertions, 0 deletions
diff --git a/gnulib b/gnulib
deleted file mode 160000
-Subproject 443bc5ffcf7429e557f4a371b0661abe98ddbc1
diff --git a/gnulib/lib/group-member.c b/gnulib/lib/group-member.c
new file mode 100644
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--- /dev/null
+++ b/gnulib/lib/group-member.c
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+/* 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 */