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Diffstat (limited to 'sysdeps/unix/sysv/linux/s390/s390-32/fchownat.c')
-rw-r--r--sysdeps/unix/sysv/linux/s390/s390-32/fchownat.c140
1 files changed, 140 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/fchownat.c b/sysdeps/unix/sysv/linux/s390/s390-32/fchownat.c
new file mode 100644
index 0000000000..b95665cad3
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/s390/s390-32/fchownat.c
@@ -0,0 +1,140 @@
+/* Copyright (C) 2005 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library 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.
+
+ The GNU C Library 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 the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#include <sysdep.h>
+#include <sys/syscall.h>
+#include <shlib-compat.h>
+#include <bp-checks.h>
+
+#include <linux/posix_types.h>
+#include "kernel-features.h"
+
+/*
+ In Linux 2.1.x the chown functions have been changed. A new function lchown
+ was introduced. The new chown now follows symlinks - the old chown and the
+ new lchown do not follow symlinks.
+ The new lchown function has the same number as the old chown had and the
+ new chown has a new number. When compiling with headers from Linux > 2.1.8x
+ it's impossible to run this libc with older kernels. In these cases libc
+ has therefore to route calls to chown to the old chown function.
+*/
+
+/* Running under Linux > 2.1.80. */
+
+#ifdef __NR_chown32
+# if __ASSUME_32BITUIDS == 0
+/* This variable is shared with all files that need to check for 32bit
+ uids. */
+extern int __libc_missing_32bit_uids;
+# endif
+#endif /* __NR_chown32 */
+
+int
+fchownat (int fd, const char *file, uid_t owner, gid_t group, int flag)
+{
+ if (flag & ~AT_SYMLINK_NOFOLLOW)
+ {
+ __set_errno (EINVAL);
+ return -1;
+ }
+
+ char *buf = NULL;
+
+ if (fd != AT_FDCWD && file[0] != '/')
+ {
+ size_t filelen = strlen (file);
+ static const char procfd[] = "/proc/self/fd/%d/%s";
+ /* Buffer for the path name we are going to use. It consists of
+ - the string /proc/self/fd/
+ - the file descriptor number
+ - the file name provided.
+ The final NUL is included in the sizeof. A bit of overhead
+ due to the format elements compensates for possible negative
+ numbers. */
+ size_t buflen = sizeof (procfd) + sizeof (int) * 3 + filelen;
+ buf = alloca (buflen);
+
+ __snprintf (buf, buflen, procfd, fd, file);
+ file = buf;
+ }
+
+ int result;
+ INTERNAL_SYSCALL_DECL (err);
+
+#if __ASSUME_32BITUIDS > 0
+ result = INTERNAL_SYSCALL (chown32, err, 3, CHECK_STRING (file), owner,
+ group);
+#else
+ static int __libc_old_chown;
+
+# ifdef __NR_chown32
+ if (__libc_missing_32bit_uids <= 0)
+ {
+ if (flag & AT_SYMLINK_NOFOLLOW)
+ result = INTERNAL_SYSCALL (lchown32, err, 3, CHECK_STRING (file),
+ owner, group);
+ else
+ result = INTERNAL_SYSCALL (chown32, err, 3, CHECK_STRING (file),
+ owner, group);
+
+ if (__builtin_expect (!INTERNAL_SYSCALL_ERROR_P (result, err), 1))
+ return result;
+ if (INTERNAL_SYSCALL_ERRNO (result, err) != ENOSYS)
+ goto fail;
+
+ __libc_missing_32bit_uids = 1;
+ }
+# endif /* __NR_chown32 */
+ if (((owner + 1) > (uid_t) ((__kernel_uid_t) -1U))
+ || ((group + 1) > (gid_t) ((__kernel_gid_t) -1U)))
+ {
+ __set_errno (EINVAL);
+ return -1;
+ }
+
+ if (!__libc_old_chown && (flag & AT_SYMLINK_NOFOLLOW) == 0)
+ {
+ result = INTERNAL_SYSCALL (chown, err, 3, CHECK_STRING (file), owner,
+ group);
+
+ if (!INTERNAL_SYSCALL_ERROR_P (result, err))
+ return result;
+ if (INTERNAL_SYSCALL_ERRNO (result, err) != ENOSYS)
+ goto fail;
+
+ __libc_old_chown = 1;
+ }
+
+ result = INTERNAL_SYSCALL (lchown, err, 3, CHECK_STRING (file), owner,
+ group);
+#endif
+
+ if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result, err), 0))
+ {
+ fail:
+ __atfct_seterrno (INTERNAL_SYSCALL_ERRNO (result, err), fd, buf);
+ result = -1;
+ }
+
+ return result;
+}