lib/write.c

   1 /* POSIX compatible write() function.
   2    Copyright (C) 2008-2009 Free Software Foundation, Inc.
   3    Written by Bruno Haible <bruno@clisp.org>, 2008.
   4
   5    This program is free software: you can redistribute it and/or modify
   6    it under the terms of the GNU Lesser General Public License as published by
   7    the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program 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
  13    GNU Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public License
  16    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  17
  18 #include <config.h>
  19
  20 /* Specification.  */
  21 #include <unistd.h>
  22
  23 /* Replace this function only if module 'sigpipe' is requested.  */
  24 #if GNULIB_SIGPIPE
  25
  26 /* On native Windows platforms, SIGPIPE does not exist.  When write() is
  27    called on a pipe with no readers, WriteFile() fails with error
  28    GetLastError() = ERROR_NO_DATA, and write() in consequence fails with
  29    error EINVAL.  */
  30
  31 # if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
  32
  33 #  include <errno.h>
  34 #  include <signal.h>
  35 #  include <io.h>
  36
  37 #  define WIN32_LEAN_AND_MEAN  /* avoid including junk */
  38 #  include <windows.h>
  39
  40 ssize_t
  41 rpl_write (int fd, const void *buf, size_t count)
  42 #undef write
  43 {
  44   ssize_t ret = write (fd, buf, count);
  45
  46   if (ret < 0)
  47     {
  48       if (GetLastError () == ERROR_NO_DATA
  49           && GetFileType ((HANDLE) _get_osfhandle (fd)) == FILE_TYPE_PIPE)
  50         {
  51           /* Try to raise signal SIGPIPE.  */
  52           raise (SIGPIPE);
  53           /* If it is currently blocked or ignored, change errno from EINVAL
  54              to EPIPE.  */
  55           errno = EPIPE;
  56         }
  57     }
  58   return ret;
  59 }
  60
  61 # endif
  62 #endif