summaryrefslogtreecommitdiffstats
path: root/lib/getugroups.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 16:58:41 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 16:58:41 +0000
commite1908ae95dd4c9d19ee4dfabfc8bf8a7f85943fe (patch)
treef5cc731bedcac0fb7fe14d952e4581e749f8bb87 /lib/getugroups.c
parentInitial commit. (diff)
downloadcoreutils-e1908ae95dd4c9d19ee4dfabfc8bf8a7f85943fe.tar.xz
coreutils-e1908ae95dd4c9d19ee4dfabfc8bf8a7f85943fe.zip
Adding upstream version 9.4.upstream/9.4upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/getugroups.c')
-rw-r--r--lib/getugroups.c128
1 files changed, 128 insertions, 0 deletions
diff --git a/lib/getugroups.c b/lib/getugroups.c
new file mode 100644
index 0000000..0145165
--- /dev/null
+++ b/lib/getugroups.c
@@ -0,0 +1,128 @@
+/* getugroups.c -- return a list of the groups a user is in
+
+ Copyright (C) 1990-1991, 1998-2000, 2003-2023 Free Software Foundation, Inc.
+
+ This file is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Lesser General Public License as
+ published by the Free Software Foundation; either version 2.1 of the
+ License, or (at your option) any later version.
+
+ This file 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 Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+/* Written by David MacKenzie. */
+
+#include <config.h>
+
+#include "getugroups.h"
+
+#include <errno.h>
+#include <limits.h>
+#include <stdio.h> /* grp.h on alpha OSF1 V2.0 uses "FILE *". */
+#include <string.h>
+#include <unistd.h>
+
+#if !HAVE_GRP_H || defined __ANDROID__
+
+/* Mingw lacks all things related to group management. The best we
+ can do is fail with ENOSYS.
+
+ Bionic declares e.g. getgrent() in <grp.h> but it isn't actually
+ defined in the library. */
+
+int
+getugroups (_GL_UNUSED int maxcount,
+ _GL_UNUSED gid_t *grouplist,
+ _GL_UNUSED char const *username,
+ _GL_UNUSED gid_t gid)
+{
+ errno = ENOSYS;
+ return -1;
+}
+
+#else /* HAVE_GRP_H */
+# include <grp.h>
+
+# define STREQ(a, b) (strcmp (a, b) == 0)
+
+/* Like 'getgroups', but for user USERNAME instead of for the current
+ process. Store at most MAXCOUNT group IDs in the GROUPLIST array.
+ If GID is not -1, store it first (if possible). GID should be the
+ group ID (pw_gid) obtained from getpwuid, in case USERNAME is not
+ listed in /etc/groups. Upon failure, set errno and return -1.
+ Otherwise, return the number of IDs we've written into GROUPLIST. */
+
+int
+getugroups (int maxcount, gid_t *grouplist, char const *username,
+ gid_t gid)
+{
+ int count = 0;
+
+ if (gid != (gid_t) -1)
+ {
+ if (maxcount != 0)
+ grouplist[count] = gid;
+ ++count;
+ }
+
+ setgrent ();
+ while (1)
+ {
+ char **cp;
+ struct group *grp;
+
+ errno = 0;
+ grp = getgrent ();
+ if (grp == NULL)
+ break;
+
+ for (cp = grp->gr_mem; *cp; ++cp)
+ {
+ int n;
+
+ if ( ! STREQ (username, *cp))
+ continue;
+
+ /* See if this group number is already on the list. */
+ for (n = 0; n < count; ++n)
+ if (grouplist && grouplist[n] == grp->gr_gid)
+ break;
+
+ /* If it's a new group number, then try to add it to the list. */
+ if (n == count)
+ {
+ if (maxcount != 0)
+ {
+ if (count >= maxcount)
+ goto done;
+ grouplist[count] = grp->gr_gid;
+ }
+ if (count == INT_MAX)
+ {
+ errno = EOVERFLOW;
+ goto done;
+ }
+ count++;
+ }
+ }
+ }
+
+ if (errno != 0)
+ count = -1;
+
+ done:
+ {
+ int saved_errno = errno;
+ endgrent ();
+ errno = saved_errno;
+ }
+
+ return count;
+}
+
+#endif /* HAVE_GRP_H */