glibc/sysdeps/unix/sysv/linux/chown.c
Ulrich Drepper 1581459f2e Update.
1998-03-07  Andreas Jaeger  <aj@arthur.rhein-neckar.de>

	* sysdeps/unix/sysv/linux/chown.c: New file for compatibility of
	Linux 2.0 and 2.1.

	* sysdeps/unix/sysv/linux/syscalls.list: Add chown.
1998-03-08 17:12:51 +00:00

69 lines
2.1 KiB
C

/* Copyright (C) 1998 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 Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <errno.h>
#include <unistd.h>
#include <sys/syscall.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.
*/
extern int __syscall_chown (const char *__file,
uid_t __owner, gid_t __group);
#ifdef __NR_lchown
/* running under Linux 2.0 or < 2.1.8x */
static int __libc_old_chown;
int
__chown (const char *file, uid_t owner, gid_t group)
{
int result;
if (!__libc_old_chown)
{
int saved_errno = errno;
result = __syscall_chown (file, owner, group);
if (result >= 0 || errno != ENOSYS)
return result;
__set_errno (saved_errno);
__libc_old_chown = 1;
}
return __lchown (file, owner, group);
}
#else
/* compiling under older kernels */
int
__chown (const char *file, uid_t owner, gid_t group)
{
return __syscall_chown (file, owner, group);
}
#endif
weak_alias (__chown, chown)