glibc/sysdeps/unix/sysv/linux/access.c
Adhemerval Zanella afcf3cd8eb New internal function __access_noerrno
Implement an internal version of __access called __access_noerrno that
avoids setting errno.  This is useful to check accessibility of files
very early on in process startup i.e. before TLS setup.  This allows
tunables to replace MALLOC_CHECK_ safely (i.e. check existence of
/etc/suid-debug to enable/disable MALLOC_CHECK) and at the same time
initialize very early so that it can override IFUNCs.

Checked on x86_64.

	* hurd/hurd.h (__hurd_fail_noerrno): New function.
	* include/unistd.h [IS_IN (rtld) || !defined SHARED]: Declare
	__access_noerrno.
	* io/access.c (__access_noerrno): New function.
	* sysdeps/mach/hurd/access.c (hurd_fail_seterrno): New function.
	(hurd_fail_seterrno): Likewise.
	(access_common): Likewise.
	(__access_noerrno): Likewise.
	* sysdeps/nacl/access.c (__access_noerrno): Likewise.
	* sysdeps/unix/sysv/linux/access.c (__access_noerrno): Likewise.
	* sysdeps/nacl/nacl-interfaces.h (NACL_CALL_NOERRNO): New
	macro.
2016-11-16 15:53:58 -02:00

48 lines
1.4 KiB
C

/* Linux implementation for access function.
Copyright (C) 2016 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 <fcntl.h>
#include <unistd.h>
#include <sysdep-cancel.h>
int
__access_noerrno (const char *file, int type)
{
int res;
INTERNAL_SYSCALL_DECL (err);
#ifdef __NR_access
res = INTERNAL_SYSCALL_CALL (access, err, file, type);
#else
res = INTERNAL_SYSCALL_CALL (faccessat, err, AT_FDCWD, file, type);
#endif
if (INTERNAL_SYSCALL_ERROR_P (res, err))
return INTERNAL_SYSCALL_ERRNO (res, err);
return 0;
}
int
__access (const char *file, int type)
{
#ifdef __NR_access
return INLINE_SYSCALL_CALL (access, file, type);
#else
return INLINE_SYSCALL_CALL (faccessat, AT_FDCWD, file, type);
#endif
}
weak_alias (__access, access)