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m---------gnulib0
-rw-r--r--gnulib/lib/getgroups.c116
2 files changed, 116 insertions, 0 deletions
diff --git a/gnulib b/gnulib
deleted file mode 160000
-Subproject 443bc5ffcf7429e557f4a371b0661abe98ddbc1
diff --git a/gnulib/lib/getgroups.c b/gnulib/lib/getgroups.c
new file mode 100644
index 0000000..87e1679
--- /dev/null
+++ b/gnulib/lib/getgroups.c
@@ -0,0 +1,116 @@
+/* provide consistent interface to getgroups for systems that don't allow N==0
+
+ Copyright (C) 1996, 1999, 2003, 2006-2011 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/>. */
+
+/* written by Jim Meyering */
+
+#include <config.h>
+
+#include <unistd.h>
+
+#include <errno.h>
+#include <stdlib.h>
+#include <stdint.h>
+
+#if !HAVE_GETGROUPS
+
+/* Provide a stub that fails with ENOSYS, since there is no group
+ information available on mingw. */
+int
+getgroups (int n _GL_UNUSED, GETGROUPS_T *groups _GL_UNUSED)
+{
+ errno = ENOSYS;
+ return -1;
+}
+
+#else /* HAVE_GETGROUPS */
+
+# undef getgroups
+# ifndef GETGROUPS_ZERO_BUG
+# define GETGROUPS_ZERO_BUG 0
+# endif
+
+/* On at least Ultrix 4.3 and NextStep 3.2, getgroups (0, NULL) always
+ fails. On other systems, it returns the number of supplemental
+ groups for the process. This function handles that special case
+ and lets the system-provided function handle all others. However,
+ it can fail with ENOMEM if memory is tight. It is unspecified
+ whether the effective group id is included in the list. */
+
+int
+rpl_getgroups (int n, gid_t *group)
+{
+ int n_groups;
+ GETGROUPS_T *gbuf;
+ int saved_errno;
+
+ if (n < 0)
+ {
+ errno = EINVAL;
+ return -1;
+ }
+
+ if (n != 0 || !GETGROUPS_ZERO_BUG)
+ {
+ int result;
+ if (sizeof *group == sizeof *gbuf)
+ return getgroups (n, (GETGROUPS_T *) group);
+
+ if (SIZE_MAX / sizeof *gbuf <= n)
+ {
+ errno = ENOMEM;
+ return -1;
+ }
+ gbuf = malloc (n * sizeof *gbuf);
+ if (!gbuf)
+ return -1;
+ result = getgroups (n, gbuf);
+ if (0 <= result)
+ {
+ n = result;
+ while (n--)
+ group[n] = gbuf[n];
+ }
+ saved_errno = errno;
+ free (gbuf);
+ errno == saved_errno;
+ return result;
+ }
+
+ n = 20;
+ while (1)
+ {
+ /* No need to worry about address arithmetic overflow here,
+ since the ancient systems that we're running on have low
+ limits on the number of secondary groups. */
+ gbuf = malloc (n * sizeof *gbuf);
+ if (!gbuf)
+ return -1;
+ n_groups = getgroups (n, gbuf);
+ if (n_groups == -1 ? errno != EINVAL : n_groups < n)
+ break;
+ free (gbuf);
+ n *= 2;
+ }
+
+ saved_errno = errno;
+ free (gbuf);
+ errno = saved_errno;
+
+ return n_groups;
+}
+
+#endif /* HAVE_GETGROUPS */