tests/test-pipe.c

   1 /* Test of pipe.
   2    Copyright (C) 2009-2025 Free Software Foundation, Inc.
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation, either version 3, or (at your option)
   7    any later version.
   8
   9    This program 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
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, see <https://www.gnu.org/licenses/>.  */
  16
  17 #include <config.h>
  18
  19 #include <unistd.h>
  20
  21 #include "signature.h"
  22 SIGNATURE_CHECK (pipe, int, (int[2]));
  23
  24 #include <fcntl.h>
  25
  26 #if defined _WIN32 && ! defined __CYGWIN__
  27 /* Get declarations of the native Windows API functions.  */
  28 # define WIN32_LEAN_AND_MEAN
  29 # include <windows.h>
  30 /* Get _get_osfhandle.  */
  31 # if GNULIB_MSVC_NOTHROW
  32 #  include "msvc-nothrow.h"
  33 # else
  34 #  include <io.h>
  35 # endif
  36 #endif
  37
  38 #include "binary-io.h"
  39 #include "macros.h"
  40
  41 /* Return true if FD is open.  */
  42 static bool
  43 is_open (int fd)
  44 {
  45 #if defined _WIN32 && ! defined __CYGWIN__
  46   /* On native Windows, the initial state of unassigned standard file
  47      descriptors is that they are open but point to an
  48      INVALID_HANDLE_VALUE, and there is no fcntl.  */
  49   return (HANDLE) _get_osfhandle (fd) != INVALID_HANDLE_VALUE;
  50 #else
  51 # ifndef F_GETFL
  52 #  error Please port fcntl to your platform
  53 # endif
  54   return 0 <= fcntl (fd, F_GETFL);
  55 #endif
  56 }
  57
  58 /* Return true if FD is not inherited to child processes.  */
  59 static bool
  60 is_cloexec (int fd)
  61 {
  62 #if defined _WIN32 && ! defined __CYGWIN__
  63   HANDLE h = (HANDLE) _get_osfhandle (fd);
  64   DWORD flags;
  65   ASSERT (GetHandleInformation (h, &flags));
  66   return (flags & HANDLE_FLAG_INHERIT) == 0;
  67 #else
  68   int flags;
  69   ASSERT ((flags = fcntl (fd, F_GETFD)) >= 0);
  70   return (flags & FD_CLOEXEC) != 0;
  71 #endif
  72 }
  73
  74 /* Return true if FD is in non-blocking mode.  */
  75 static bool
  76 is_nonblocking (int fd)
  77 {
  78 #if defined _WIN32 && ! defined __CYGWIN__
  79   /* We don't use the non-blocking mode for sockets here.  */
  80   return 0;
  81 #else
  82   int flags;
  83   ASSERT ((flags = fcntl (fd, F_GETFL)) >= 0);
  84   return (flags & O_NONBLOCK) != 0;
  85 #endif
  86 }
  87
  88 int
  89 main ()
  90 {
  91   int fd[2];
  92
  93   fd[0] = -1;
  94   fd[1] = -1;
  95   ASSERT (pipe (fd) >= 0);
  96   ASSERT (fd[0] >= 0);
  97   ASSERT (fd[1] >= 0);
  98   ASSERT (fd[0] != fd[1]);
  99   ASSERT (is_open (fd[0]));
 100   ASSERT (is_open (fd[1]));
 101   ASSERT (!is_cloexec (fd[0]));
 102   ASSERT (!is_cloexec (fd[1]));
 103   ASSERT (!is_nonblocking (fd[0]));
 104   ASSERT (!is_nonblocking (fd[1]));
 105
 106   return test_exit_status;
 107 }