X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fchown.c;h=b212198552be6b581207b9ef3514f1a6f11012e4;hb=23eecb48e39afd0d267d64d40ba6bf97aa865e13;hp=5c8b32e0272fd8b3749790fe3b0caff7d065c6dd;hpb=0632e115747ff96e93330c88f536d7354a7ce507;p=gnulib.git
diff --git a/lib/chown.c b/lib/chown.c
index 5c8b32e02..b21219855 100644
--- a/lib/chown.c
+++ b/lib/chown.c
@@ -1,12 +1,12 @@
/* provide consistent interface to chown for systems that don't interpret
- an ID of -1 as meaning `don't change the corresponding ID'.
+ an ID of -1 as meaning "don't change the corresponding ID".
- Copyright (C) 1997, 2004, 2005, 2006 Free Software Foundation, Inc.
+ Copyright (C) 1997, 2004-2007, 2009-2013 Free Software Foundation, Inc.
- This program is free software; you can redistribute it and/or modify
+ 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 2, or (at your option)
- any later version.
+ 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
@@ -14,54 +14,78 @@
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, write to the Free Software Foundation,
- Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+ along with this program. If not, see . */
/* written by Jim Meyering */
#include
-/* Disable the definition of chown to rpl_chown (from config.h) in this
- file. Otherwise, we'd get conflicting prototypes for rpl_chown on
- most systems. */
-#undef chown
+/* Specification. */
+#include
+#include
+#include
#include
-#include
+#include
#include
-#include
-#include
-#include
-#include "stat-macros.h"
+#if !HAVE_CHOWN
+
+/* Simple stub that always fails with ENOSYS, for mingw. */
+int
+chown (const char *file _GL_UNUSED, uid_t uid _GL_UNUSED,
+ gid_t gid _GL_UNUSED)
+{
+ errno = ENOSYS;
+ return -1;
+}
+
+#else /* HAVE_CHOWN */
+
+/* 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'.
+ "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 st;
+ bool stat_valid = false;
+ int result;
+
+# if CHOWN_CHANGE_TIME_BUG
+ if (gid != (gid_t) -1 || uid != (uid_t) -1)
{
- struct stat file_stats;
+ if (stat (file, &st))
+ return -1;
+ stat_valid = true;
+ }
+# endif
+# if CHOWN_FAILS_TO_HONOR_ID_OF_NEGATIVE_ONE
+ if (gid == (gid_t) -1 || uid == (uid_t) -1)
+ {
/* Stat file to get id(s) that should remain unchanged. */
- if (stat (file, &file_stats))
- return -1;
-
+ if (!stat_valid && stat (file, &st))
+ return -1;
if (gid == (gid_t) -1)
- gid = file_stats.st_gid;
-
+ gid = st.st_gid;
if (uid == (uid_t) -1)
- uid = file_stats.st_uid;
+ uid = st.st_uid;
}
-#endif
+# endif
-#if CHOWN_MODIFIES_SYMLINK
+# if CHOWN_MODIFIES_SYMLINK
{
/* Handle the case in which the system-supplied chown function
does *not* follow symlinks. Instead, it changes permissions
@@ -71,31 +95,62 @@ rpl_chown (const char *file, uid_t uid, gid_t gid)
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))))
+ || (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;
- }
+ int saved_errno;
+ bool fchown_socket_failure;
+
+ result = fchown (fd, uid, gid);
+ saved_errno = errno;
+
+ /* POSIX says fchown can fail with errno == EINVAL on sockets
+ and pipes, so fall back on chown in that case. */
+ fchown_socket_failure =
+ (result != 0 && saved_errno == EINVAL
+ && fstat (fd, &st) == 0
+ && (S_ISFIFO (st.st_mode) || S_ISSOCK (st.st_mode)));
+
+ close (fd);
+
+ if (! fchown_socket_failure)
+ {
+ errno = saved_errno;
+ return result;
+ }
}
else if (errno != EACCES)
return -1;
}
-#endif
+# endif
+
+# if CHOWN_TRAILING_SLASH_BUG
+ if (!stat_valid)
+ {
+ size_t len = strlen (file);
+ if (len && file[len - 1] == '/' && stat (file, &st))
+ return -1;
+ }
+# endif
- return chown (file, uid, gid);
+ result = chown (file, uid, gid);
+
+# if CHOWN_CHANGE_TIME_BUG
+ if (result == 0 && stat_valid
+ && (uid == st.st_uid || uid == (uid_t) -1)
+ && (gid == st.st_gid || gid == (gid_t) -1))
+ {
+ /* No change in ownership, but at least one argument was not -1,
+ so we are required to update ctime. Since chown succeeded,
+ we assume that chmod will do likewise. Fortunately, on all
+ known systems where a 'no-op' chown skips the ctime update, a
+ 'no-op' chmod still does the trick. */
+ result = chmod (file, st.st_mode & (S_IRWXU | S_IRWXG | S_IRWXO
+ | S_ISUID | S_ISGID | S_ISVTX));
+ }
+# endif
+
+ return result;
}
+
+#endif /* HAVE_CHOWN */