glibc/sysdeps/unix/sysv/linux/pread64.c
Roland McGrath 4b172769b2 * sysdeps/unix/sysv/linux/pread.c: __NR_pread64 may be defined
instead of __NR_pread.
	* sysdeps/unix/sysv/linux/pread64.c: Likewise.
	* sysdeps/unix/sysv/linux/pwrite.c: __NR_pwrite64 may be defined
	instead of __NR_pwrite.
	* sysdeps/unix/sysv/linux/pwrite64.c: Likewise.
2002-09-14 08:32:37 +00:00

80 lines
2.4 KiB
C

/* Copyright (C) 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
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 <endian.h>
#include <unistd.h>
#include <sysdep.h>
#include <sys/syscall.h>
#include <bp-checks.h>
#include "kernel-features.h"
#ifdef __NR_pread64 /* Newer kernels renamed but it's the same. */
# ifdef __NR_pread
# error "__NR_pread and __NR_pread64 both defined???"
# endif
# define __NR_pread __NR_pread64
#endif
#if defined __NR_pread || __ASSUME_PREAD_SYSCALL > 0
extern ssize_t __syscall_pread (int fd, void *__unbounded buf, size_t count,
off_t offset_hi, off_t offset_lo);
# if __ASSUME_PREAD_SYSCALL == 0
static ssize_t __emulate_pread64 (int fd, void *buf, size_t count,
off64_t offset) internal_function;
# endif
ssize_t
__libc_pread64 (fd, buf, count, offset)
int fd;
void *buf;
size_t count;
off64_t offset;
{
ssize_t result;
/* First try the syscall. */
result = INLINE_SYSCALL (pread, 5, fd, CHECK_N (buf, count), count,
__LONG_LONG_PAIR ((off_t) (offset >> 32),
(off_t) (offset & 0xffffffff)));
# if __ASSUME_PREAD_SYSCALL == 0
if (result == -1 && errno == ENOSYS)
/* No system call available. Use the emulation. */
result = __emulate_pread64 (fd, buf, count, offset);
# endif
return result;
}
weak_alias (__libc_pread64, __pread64)
weak_alias (__libc_pread64, pread64)
# define __libc_pread64(fd, buf, count, offset) \
static internal_function __emulate_pread64 (fd, buf, count, offset)
#endif
# if __ASSUME_PREAD_SYSCALL == 0
# include <sysdeps/posix/pread64.c>
#endif