sysdeps/unix/sysv/linux/preadv.c

   1 /* Copyright (C) 2009-2021 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    <https://www.gnu.org/licenses/>.  */
  17
  18 #include <sys/uio.h>
  19 #include <sysdep-cancel.h>
  20
  21 #ifndef __OFF_T_MATCHES_OFF64_T
  22
  23 # ifdef __ASSUME_PREADV
  24
  25 ssize_t
  26 preadv (int fd, const struct iovec *vector, int count, off_t offset)
  27 {
  28   return SYSCALL_CANCEL (preadv, fd, vector, count, LO_HI_LONG (offset));
  29 }
  30 # else
  31 static ssize_t __atomic_preadv_replacement (int, const struct iovec *,
  32                                             int, off_t);
  33 ssize_t
  34 preadv (int fd, const struct iovec *vector, int count, off_t offset)
  35 {
  36   ssize_t result = SYSCALL_CANCEL (preadv, fd, vector, count,
  37                                    LO_HI_LONG (offset));
  38   if (result >= 0 || errno != ENOSYS)
  39     return result;
  40   return __atomic_preadv_replacement (fd, vector, count, offset);
  41 }
  42 #  define PREADV static __atomic_preadv_replacement
  43 #  define PREAD __pread
  44 #  define OFF_T off_t
  45 #  include <sysdeps/posix/preadv_common.c>
  46 # endif /* __ASSUME_PREADV  */
  47
  48 libc_hidden_def (preadv)
  49 #endif