+++ /dev/null
-/* provide consistent interface to chown for systems that don't interpret
- an ID of -1 as meaning `don't change the corresponding ID'.
-
- Copyright (C) 1997, 2004, 2005, 2006, 2007 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>
-
-/* Specification. */
-#include <unistd.h>
-
-#include <stdbool.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <errno.h>
-
-/* Below we refer to the system's chown(). */
-#undef chown
-
-/* The results of open() in this file are not used with fchdir,
- therefore save some unnecessary work in fchdir.c. */
-#undef open
-#undef close
-
-/* Provide a more-closely POSIX-conforming version of chown on
- systems with one or both of the following problems:
- - chown doesn't treat an ID of -1 as meaning
- `don't change the corresponding ID'.
- - chown doesn't dereference symlinks. */
-
-int
-rpl_chown (const char *file, uid_t uid, gid_t gid)
-{
-#if CHOWN_FAILS_TO_HONOR_ID_OF_NEGATIVE_ONE
- if (gid == (gid_t) -1 || uid == (uid_t) -1)
- {
- struct stat file_stats;
-
- /* Stat file to get id(s) that should remain unchanged. */
- if (stat (file, &file_stats))
- return -1;
-
- if (gid == (gid_t) -1)
- gid = file_stats.st_gid;
-
- if (uid == (uid_t) -1)
- uid = file_stats.st_uid;
- }
-#endif
-
-#if CHOWN_MODIFIES_SYMLINK
- {
- /* Handle the case in which the system-supplied chown function
- does *not* follow symlinks. Instead, it changes permissions
- on the symlink itself. To work around that, we open the
- file (but this can fail due to lack of read or write permission) and
- use fchown on the resulting descriptor. */
- int open_flags = O_NONBLOCK | O_NOCTTY;
- int fd = open (file, O_RDONLY | open_flags);
- if (0 <= fd
- || (errno == EACCES
- && 0 <= (fd = open (file, O_WRONLY | open_flags))))
- {
- int result = fchown (fd, uid, gid);
- int saved_errno = errno;
-
- /* POSIX says fchown can fail with errno == EINVAL on sockets,
- so fall back on chown in that case. */
- struct stat sb;
- bool fchown_socket_failure =
- (result != 0 && saved_errno == EINVAL
- && fstat (fd, &sb) == 0 && S_ISFIFO (sb.st_mode));
-
- close (fd);
-
- if (! fchown_socket_failure)
- {
- errno = saved_errno;
- return result;
- }
- }
- else if (errno != EACCES)
- return -1;
- }
-#endif
-
- return chown (file, uid, gid);
-}