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 2.1 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, see <http://www.gnu.org/licenses/>.
  18  *
  19  * Author: Simon McVittie <simon.mcvittie@collabora.co.uk>
  20  */
  21
  22 #include <errno.h>
  23 #include <unistd.h>
  24
  25 #include <gio/gio.h>
  26
  27 #include "test-io-stream.h"
  28 #include "test-pipe-unix.h"
  29
  30 #ifdef G_OS_UNIX
  31 #   include <gio/gunixinputstream.h>
  32 #   include <gio/gunixoutputstream.h>
  33 #else
  34 #   error This module only exists on Unix
  35 #endif
  36
  37 /**
  38  * test_pipe:
  39  * @is: (out) (optional): used to return a #GInputStream
  40  * @os: (out) (optional): used to return a #GOutputStream
  41  * @error: used to raise an error
  42  *
  43  * Return a "pipe to self" connecting @is to @os. This can be used
  44  * as a unidirectional pipe to or from a child process, for instance.
  45  *
  46  * See test_bidi_pipe() if you want to emulate a bidirectional pipe
  47  * via a pair of unidirectional pipes.
  48  *
  49  * Returns: %TRUE on success
  50  */
  51 gboolean
  52 test_pipe (GInputStream  **is,
  53            GOutputStream **os,
  54            GError        **error)
  55 {
  56   int pipefd[2];
  57   int ret;
  58
  59   ret = pipe (pipefd);
  60
  61   if (ret != 0)
  62     {
  63       int e = errno;
  64
  65       g_set_error (error, G_IO_ERROR, g_io_error_from_errno (e),
  66                    "%s", g_strerror (e));
  67       return FALSE;
  68     }
  69
  70   if (is != NULL)
  71     *is = g_unix_input_stream_new (pipefd[0], TRUE);
  72   else
  73     close (pipefd[0]);
  74
  75   if (os != NULL)
  76     *os = g_unix_output_stream_new (pipefd[1], TRUE);
  77   else
  78     close (pipefd[1]);
  79
  80   return TRUE;
  81 }
  82
  83 /**
  84  * test_bidi_pipe:
  85  * @left: (out) (optional): used to return one #GIOStream
  86  * @right: (out) (optional): used to return the other #GIOStream
  87  * @error: used to raise an error
  88  *
  89  * Return two #GIOStream<!---->s connected to each other with pipes.
  90  * The "left" input stream is connected by a unidirectional pipe
  91  * to the "right" output stream, and vice versa. This can be used
  92  * as a bidirectional pipe to a child process, for instance.
  93  *
  94  * See test_pipe() if you only need a one-way pipe.
  95  *
  96  * Returns: %TRUE on success
  97  */
  98 gboolean
  99 test_bidi_pipe (GIOStream **left,
 100                 GIOStream **right,
 101                 GError    **error)
 102 {
 103   GInputStream *left_in = NULL;
 104   GOutputStream *left_out = NULL;
 105   GInputStream *right_in = NULL;
 106   GOutputStream *right_out = NULL;
 107   gboolean ret = FALSE;
 108
 109   if (!test_pipe (&left_in, &right_out, error))
 110     goto out;
 111
 112   if (!test_pipe (&right_in, &left_out, error))
 113     goto out;
 114
 115   if (left != NULL)
 116     *left = test_io_stream_new (left_in, left_out);
 117
 118   if (right != NULL)
 119     *right = test_io_stream_new (right_in, right_out);
 120
 121   ret = TRUE;
 122
 123 out:
 124   g_clear_object (&left_in);
 125   g_clear_object (&left_out);
 126   g_clear_object (&right_in);
 127   g_clear_object (&right_out);
 128   return ret;
 129 }