gio/tests/test-pipe-unix.c

   1 /* Unix pipe-to-self. This is a utility module for tests, not a test.
   2  *
   3  * Copyright © 2008-2010 Red Hat, Inc.
   4  * Copyright © 2011 Nokia Corporation
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General
  17  * Public License along with this library; if not, write to the
  18  * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  19  * Boston, MA 02111-1307, USA.
  20  *
  21  * Author: Simon McVittie <simon.mcvittie@collabora.co.uk>
  22  */
  23
  24 #include <errno.h>
  25 #include <unistd.h>
  26
  27 #include <gio/gio.h>
  28
  29 #include "test-io-stream.h"
  30
  31 #ifdef G_OS_UNIX
  32 #   include <gio/gunixinputstream.h>
  33 #   include <gio/gunixoutputstream.h>
  34 #else
  35 #   error This module only exists on Unix
  36 #endif
  37
  38 /*
  39  * test_pipe:
  40  * @is: (out) (allow-none): used to return a #GInputStream
  41  * @os: (out) (allow-none): used to return a #GOutputStream
  42  * @error: used to raise an error
  43  *
  44  * Return a "pipe to self" connecting @is to @os. This can be used
  45  * as a unidirectional pipe to or from a child process, for instance.
  46  *
  47  * See test_bidi_pipe() if you want to emulate a bidirectional pipe
  48  * via a pair of unidirectional pipes.
  49  *
  50  * Returns: %TRUE on success
  51  */
  52 gboolean
  53 test_pipe (GInputStream  **is,
  54            GOutputStream **os,
  55            GError        **error)
  56 {
  57   int pipefd[2];
  58   int ret;
  59
  60   ret = pipe (pipefd);
  61
  62   if (ret != 0)
  63     {
  64       int e = errno;
  65
  66       g_set_error (error, G_IO_ERROR, g_io_error_from_errno (e),
  67                    "%s", g_strerror (e));
  68       return FALSE;
  69     }
  70
  71   if (is != NULL)
  72     *is = g_unix_input_stream_new (pipefd[0], TRUE);
  73   else
  74     close (pipefd[0]);
  75
  76   if (os != NULL)
  77     *os = g_unix_output_stream_new (pipefd[1], TRUE);
  78   else
  79     close (pipefd[1]);
  80
  81   return TRUE;
  82 }
  83
  84 /*
  85  * test_bidi_pipe:
  86  * @left: (out) (allow-none): used to return one #GIOStream
  87  * @right: (out) (allow-none): used to return the other #GIOStream
  88  * @error: used to raise an error
  89  *
  90  * Return two #GIOStream<!---->s connected to each other with pipes.
  91  * The "left" input stream is connected by a unidirectional pipe
  92  * to the "right" output stream, and vice versa. This can be used
  93  * as a bidirectional pipe to a child process, for instance.
  94  *
  95  * See test_pipe() if you only need a one-way pipe.
  96  *
  97  * Returns: %TRUE on success
  98  */
  99 gboolean
 100 test_bidi_pipe (GIOStream **left,
 101                 GIOStream **right,
 102                 GError    **error)
 103 {
 104   GInputStream *left_in = NULL;
 105   GOutputStream *left_out = NULL;
 106   GInputStream *right_in = NULL;
 107   GOutputStream *right_out = NULL;
 108   gboolean ret;
 109
 110   if (!test_pipe (&left_in, &right_out, error))
 111     goto out;
 112
 113   if (!test_pipe (&right_in, &left_out, error))
 114     goto out;
 115
 116   if (left != NULL)
 117     *left = test_io_stream_new (left_in, left_out);
 118
 119   if (right != NULL)
 120     *right = test_io_stream_new (right_in, right_out);
 121
 122   ret = TRUE;
 123
 124 out:
 125   g_clear_object (&left_in);
 126   g_clear_object (&left_out);
 127   g_clear_object (&right_in);
 128   g_clear_object (&right_out);
 129   return ret;
 130 }