sysdeps/unix/sysv/linux/wordsize-64/pwritev.c

   1 /* 64-bit pwritev.
   2    Copyright (C) 2012-2015 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   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.
   9
  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.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include <stddef.h>
  21 #include <sys/param.h>
  22 /* Hide the pwritev64 declaration.  */
  23 #define pwritev64 __redirect_pwritev64
  24 #include <sys/uio.h>
  25
  26 #include <sysdep-cancel.h>
  27 #include <sys/syscall.h>
  28 #include <kernel-features.h>
  29
  30 #ifndef __ASSUME_PWRITEV
  31 static ssize_t __atomic_pwritev_replacement (int, const struct iovec *,
  32                                              int, off_t) internal_function;
  33 #endif
  34
  35 ssize_t
  36 pwritev (int fd, const struct iovec *vector, int count, off_t offset)
  37 {
  38 #ifdef __NR_pwritev
  39   ssize_t result;
  40
  41   if (SINGLE_THREAD_P)
  42     result = INLINE_SYSCALL (pwritev, 4, fd, vector, count, offset);
  43   else
  44     {
  45       int oldtype = LIBC_CANCEL_ASYNC ();
  46
  47       result = INLINE_SYSCALL (pwritev, 4, fd, vector, count, offset);
  48
  49       LIBC_CANCEL_RESET (oldtype);
  50     }
  51 # ifdef __ASSUME_PWRITEV
  52   return result;
  53 # endif
  54 #endif
  55
  56 #ifndef __ASSUME_PWRITEV
  57 # ifdef __NR_pwritev
  58   if (result >= 0 || errno != ENOSYS)
  59     return result;
  60 # endif
  61
  62   return __atomic_pwritev_replacement (fd, vector, count, offset);
  63 #endif
  64 }
  65 #undef pwritev64
  66 strong_alias (pwritev, pwritev64)
  67
  68 #ifndef __ASSUME_PWRITEV
  69 # define PWRITE __pwrite
  70 # define PWRITEV static internal_function __atomic_pwritev_replacement
  71 # define OFF_T off_t
  72 # include <sysdeps/posix/pwritev.c>
  73 #endif