sysdeps/unix/sysv/linux/preadv64.c

   1 /* Copyright (C) 2016 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <sys/uio.h>
  19 #include <sysdep-cancel.h>
  20
  21 #ifdef __ASSUME_PREADV
  22
  23 # ifndef __NR_preadv64
  24 #  define __NR_preadv64 __NR_preadv
  25 # endif
  26
  27 ssize_t
  28 preadv64 (int fd, const struct iovec *vector, int count, off64_t offset)
  29 {
  30   return SYSCALL_CANCEL (preadv64, fd, vector, count,
  31                          __ALIGNMENT_ARG SYSCALL_LL64 (offset));
  32 }
  33 #else
  34 static ssize_t __atomic_preadv64_replacement (int, const struct iovec *,
  35                                               int, off64_t) internal_function;
  36 ssize_t
  37 preadv64 (int fd, const struct iovec *vector, int count, off64_t offset)
  38 {
  39 #ifdef __NR_preadv64
  40   ssize_t result = SYSCALL_CANCEL (preadv64, fd, vector, count,
  41                                    __ALIGNMENT_ARG SYSCALL_LL64 (offset));
  42   if (result >= 0 || errno != ENOSYS)
  43     return result;
  44 #endif
  45   return __atomic_preadv64_replacement (fd, vector, count, offset);
  46 }
  47 # define PREADV static internal_function __atomic_preadv64_replacement
  48 # define PREAD __pread64
  49 # define OFF_T off64_t
  50 # include <sysdeps/posix/preadv.c>
  51 #endif
  52
  53 #if __WORDSIZE == 64 && !defined (__ASSUME_OFF_DIFF_OFF64)
  54 strong_alias (preadv64, preadv)
  55 #endif