1 /* Copyright (C) 1997-2000,2002,2003,2004,2006 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
25 #include <sysdep-cancel.h>
26 #include <sys/syscall.h>
27 #include <bp-checks.h>
29 #include <kernel-features.h>
31 #ifdef __NR_pread64 /* Newer kernels renamed but it's the same. */
33 # error "__NR_pread and __NR_pread64 both defined???"
35 # define __NR_pread __NR_pread64
38 #if defined __NR_pread || __ASSUME_PREAD_SYSCALL > 0
40 # if __ASSUME_PREAD_SYSCALL == 0
41 static ssize_t __emulate_pread (int fd, void *buf, size_t count,
42 off_t offset) internal_function;
47 #ifdef NO_CANCELLATION
48 inline __attribute ((always_inline))
50 do_pread (int fd, void *buf, size_t count, off_t offset)
54 /* First try the syscall. */
55 assert (sizeof (offset) == 4);
56 result = INLINE_SYSCALL (pread, 5, fd, CHECK_N (buf, count), count,
57 __LONG_LONG_PAIR (offset >> 31, offset));
58 # if __ASSUME_PREAD_SYSCALL == 0
59 if (result == -1 && errno == ENOSYS)
60 /* No system call available. Use the emulation. */
61 result = __emulate_pread (fd, buf, count, offset);
69 __libc_pread (fd, buf, count, offset)
76 return do_pread (fd, buf, count, offset);
78 int oldtype = LIBC_CANCEL_ASYNC ();
80 ssize_t result = do_pread (fd, buf, count, offset);
82 LIBC_CANCEL_RESET (oldtype);
87 strong_alias (__libc_pread, __pread)
88 weak_alias (__libc_pread, pread)
90 # define __libc_pread(fd, buf, count, offset) \
91 static internal_function __emulate_pread (fd, buf, count, offset)
94 #if __ASSUME_PREAD_SYSCALL == 0
95 # include <sysdeps/posix/pread.c>