Mercurial > gnulib
view lib/getgroups.c @ 17363:5a51fb7777a9
sys_select, sys_time: port 2013-01-30 Solaris 2.6 fix to Cygwin
Problem reported by Marco Atzeri in
<http://lists.gnu.org/archive/html/bug-gnulib/2013-03/msg00000.html>.
* lib/sys_select.in.h [HAVE_SYS_SELECT_H && _CYGWIN_SYS_TIME_H]:
Simply delegate to the system <sys/select.h> in this case too.
Also, pay attention to _GL_SYS_SELECT_H_REDIRECT_FROM_SYS_TIME_H only
if OSF/1, since otherwise Cygwin breaks, and it doesn't seem to
be needed on Solaris either.
* lib/sys_time.in.h [_CYGWIN_SYS_TIME_H]:
Simply delgate to the system <sys/time.h> in this case.
author | Paul Eggert <eggert@cs.ucla.edu> |
---|---|
date | Tue, 19 Mar 2013 09:08:47 -0700 |
parents | e542fd46ad6f |
children | 8a7bf20440f8 |
line wrap: on
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/* provide consistent interface to getgroups for systems that don't allow N==0 Copyright (C) 1996, 1999, 2003, 2006-2013 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 */