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/* Copyright (C) 1998,1999,2000,2002,2003,2004,2006
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, see
<http://www.gnu.org/licenses/>. */
#include <errno.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.
*/
extern int __chown_is_lchown (const char *__file, uid_t __owner,
gid_t __group);
extern int __real_chown (const char *__file, uid_t __owner, gid_t __group);
#if defined __NR_lchown || __ASSUME_LCHOWN_SYSCALL > 0
/* 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
__real_chown (const char *file, uid_t owner, gid_t group)
{
# if __ASSUME_LCHOWN_SYSCALL == 0
static int __libc_old_chown;
int result;
if (!__libc_old_chown)
{
int saved_errno = errno;
# ifdef __NR_chown32
if (__libc_missing_32bit_uids <= 0)
{
int result;
int saved_errno = errno;
result = INLINE_SYSCALL (chown32, 3, CHECK_STRING (file), owner, group);
if (result == 0 || errno != ENOSYS)
return result;
__set_errno (saved_errno);
__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;
}
result = INLINE_SYSCALL (chown, 3, CHECK_STRING (file), owner, group);
if (result >= 0 || errno != ENOSYS)
return result;
__set_errno (saved_errno);
__libc_old_chown = 1;
}
return __lchown (file, owner, group);
# elif __ASSUME_32BITUIDS
/* This implies __ASSUME_LCHOWN_SYSCALL. */
return INLINE_SYSCALL (chown32, 3, CHECK_STRING (file), owner, group);
# else
/* !__ASSUME_32BITUIDS && ASSUME_LCHOWN_SYSCALL */
# ifdef __NR_chown32
if (__libc_missing_32bit_uids <= 0)
{
int result;
int saved_errno = errno;
result = INLINE_SYSCALL (chown32, 3, CHECK_STRING (file), owner, group);
if (result == 0 || errno != ENOSYS)
return result;
__set_errno (saved_errno);
__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;
}
return INLINE_SYSCALL (chown, 3, CHECK_STRING (file), owner, group);
# endif
}
#endif
#if !defined __NR_lchown && __ASSUME_LCHOWN_SYSCALL == 0
/* Compiling under older kernels. */
int
__chown_is_lchown (const char *file, uid_t owner, gid_t group)
{
return INLINE_SYSCALL (chown, 3, CHECK_STRING (file), owner, group);
}
#elif SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
/* Compiling for compatibiity. */
int
attribute_compat_text_section
__chown_is_lchown (const char *file, uid_t owner, gid_t group)
{
return __lchown (file, owner, group);
}
#endif
#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
compat_symbol (libc, __chown_is_lchown, chown, GLIBC_2_0);
#endif
#ifdef __NR_lchown
versioned_symbol (libc, __real_chown, chown, GLIBC_2_1);
strong_alias (__real_chown, __chown)
#else
strong_alias (__chown_is_lchown, __chown_is_lchown21)
versioned_symbol (libc, __chown_is_lchown21, chown, GLIBC_2_1);
strong_alias (__chown_is_lchown, __chown)
#endif
libc_hidden_def (__chown)
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