glibc/nptl/sysdeps/unix/sysv/linux/llseek.c

69 lines
2.3 KiB
C

/* Long-long seek operation.
Copyright (C) 1996,1997,1998,1999,2000,2002 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 <sys/types.h>
#include <sysdep.h>
#include <sys/syscall.h>
#include <nptl/pthreadP.h>
#include <tls.h>
extern int __syscall__llseek (int fd, off_t offset_hi, off_t offset_lo,
loff_t *__unbounded result, int whence);
/* Seek to OFFSET on FD, starting from WHENCE. */
extern loff_t __llseek (int fd, loff_t offset, int whence);
loff_t
__llseek (int fd, loff_t offset, int whence)
{
loff_t result;
#ifndef NOT_IN_libc
if (__builtin_expect (THREAD_GETMEM (THREAD_SELF,
header.data.multiple_threads) == 0, 1))
return (loff_t) (INLINE_SYSCALL (_llseek, 5, fd, (off_t) (offset >> 32),
(off_t) (offset & 0xffffffff),
__ptrvalue (&result), whence) ?: result);
int oldtype = LIBC_CANCEL_ASYNC ();
#endif
int retval = INLINE_SYSCALL (_llseek, 5, fd, (off_t) (offset >> 32),
(off_t) (offset & 0xffffffff),
__ptrvalue (&result), whence);
#ifndef NOT_IN_libc
LIBC_CANCEL_RESET (oldtype);
#endif
return (loff_t) (retval ?: result);
}
weak_alias (__llseek, llseek)
strong_alias (__llseek, __libc_lseek64)
strong_alias (__llseek, __lseek64)
weak_alias (__llseek, lseek64)
/* llseek doesn't have a prototype. Since the second parameter is a
64bit type, this results in wrong behaviour if no prototype is
provided. */
link_warning (llseek, "\
the `llseek' function may be dangerous; use `lseek64' instead.")