1 /* GIO - GLib Input, Output and Streaming Library
3 * Copyright © 2009 Codethink Limited
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
7 * by the Free Software Foundation; either version 2 of the licence or (at
8 * your option) any later version.
10 * See the included COPYING file for more information.
12 * Authors: Ryan Lortie <desrt@desrt.ca>
16 * SECTION: gunixfdmessage
17 * @title: GUnixFDMessage
18 * @short_description: A GSocketControlMessage containing a #GUnixFDList
19 * @see_also: #GUnixConnection, #GUnixFDList, #GSocketControlMessage
21 * This #GSocketControlMessage contains a #GUnixFDList. It may be sent
22 * using g_socket_send_message() and received using
23 * g_socket_receive_message() over UNIX sockets (ie: sockets in the
24 * %G_SOCKET_ADDRESS_UNIX family). The file descriptors are copied
25 * between processes by the kernel.
27 * For an easier way to send and receive file descriptors over
28 * stream-oriented UNIX sockets, see g_unix_connection_send_fd() and
29 * g_unix_connection_receive_fd().
34 #include <sys/types.h>
35 #include <sys/socket.h>
41 #include "gunixfdmessage.h"
42 #include "gunixfdlist.h"
48 G_DEFINE_TYPE (GUnixFDMessage, g_unix_fd_message,
49 G_TYPE_SOCKET_CONTROL_MESSAGE);
51 struct _GUnixFDMessagePrivate
57 g_unix_fd_message_get_size (GSocketControlMessage *message)
59 GUnixFDMessage *fd_message = G_UNIX_FD_MESSAGE (message);
61 return g_unix_fd_list_get_length (fd_message->priv->list) * sizeof (gint);
65 g_unix_fd_message_get_level (GSocketControlMessage *message)
71 g_unix_fd_message_get_msg_type (GSocketControlMessage *message)
76 static GSocketControlMessage *
77 g_unix_fd_message_deserialize (int level,
82 GSocketControlMessage *message;
87 if (level != SOL_SOCKET ||
93 g_warning ("Kernel returned non-integral number of fds");
98 n = size / sizeof (gint);
100 for (i = 0; i < n; i++)
103 s = fcntl (fds[i], F_SETFD, FD_CLOEXEC);
104 while (s < 0 && errno == EINTR);
108 g_warning ("Error setting close-on-exec flag on incoming fd: %s",
114 list = g_unix_fd_list_new_from_array (fds, n);
115 message = g_unix_fd_message_new_with_fd_list (list);
116 g_object_unref (list);
122 g_unix_fd_message_serialize (GSocketControlMessage *message,
125 GUnixFDMessage *fd_message = G_UNIX_FD_MESSAGE (message);
129 fds = g_unix_fd_list_peek_fds (fd_message->priv->list, &n_fds);
130 memcpy (data, fds, sizeof (gint) * n_fds);
134 g_unix_fd_message_set_property (GObject *object, guint prop_id,
135 const GValue *value, GParamSpec *pspec)
137 GUnixFDMessage *message = G_UNIX_FD_MESSAGE (object);
139 g_assert (message->priv->list == NULL);
140 g_assert_cmpint (prop_id, ==, 1);
142 message->priv->list = g_value_dup_object (value);
144 if (message->priv->list == NULL)
145 message->priv->list = g_unix_fd_list_new ();
149 * g_unix_fd_message_get_fd_list:
150 * @message: a #GUnixFDMessage
152 * Gets the #GUnixFDList contained in @message. This function does not
153 * return a reference to the caller, but the returned list is valid for
154 * the lifetime of @message.
156 * Returns: the #GUnixFDList from @message
161 g_unix_fd_message_get_fd_list (GUnixFDMessage *message)
163 return message->priv->list;
167 g_unix_fd_message_get_property (GObject *object, guint prop_id,
168 GValue *value, GParamSpec *pspec)
170 GUnixFDMessage *message = G_UNIX_FD_MESSAGE (object);
172 g_assert_cmpint (prop_id, ==, 1);
174 g_value_set_object (value, g_unix_fd_message_get_fd_list (message));
178 g_unix_fd_message_init (GUnixFDMessage *message)
180 message->priv = G_TYPE_INSTANCE_GET_PRIVATE (message,
181 G_TYPE_UNIX_FD_MESSAGE,
182 GUnixFDMessagePrivate);
186 g_unix_fd_message_finalize (GObject *object)
188 GUnixFDMessage *message = G_UNIX_FD_MESSAGE (object);
190 g_object_unref (message->priv->list);
192 G_OBJECT_CLASS (g_unix_fd_message_parent_class)
197 g_unix_fd_message_class_init (GUnixFDMessageClass *class)
199 GSocketControlMessageClass *scm_class = G_SOCKET_CONTROL_MESSAGE_CLASS (class);
200 GObjectClass *object_class = G_OBJECT_CLASS (class);
202 g_type_class_add_private (class, sizeof (GUnixFDMessagePrivate));
203 scm_class->get_size = g_unix_fd_message_get_size;
204 scm_class->get_level = g_unix_fd_message_get_level;
205 scm_class->get_type = g_unix_fd_message_get_msg_type;
206 scm_class->serialize = g_unix_fd_message_serialize;
207 scm_class->deserialize = g_unix_fd_message_deserialize;
208 object_class->finalize = g_unix_fd_message_finalize;
209 object_class->set_property = g_unix_fd_message_set_property;
210 object_class->get_property = g_unix_fd_message_get_property;
212 g_object_class_install_property (object_class, 1,
213 g_param_spec_object ("fd-list", "file descriptor list",
214 "The GUnixFDList object to send with the message",
215 G_TYPE_UNIX_FD_LIST, G_PARAM_STATIC_STRINGS |
216 G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY));
220 * g_unix_fd_message_new:
222 * Creates a new #GUnixFDMessage containing an empty file descriptor
225 * Returns: a new #GUnixFDMessage
229 GSocketControlMessage *
230 g_unix_fd_message_new (void)
232 return g_object_new (G_TYPE_UNIX_FD_MESSAGE, NULL);
236 * g_unix_fd_message_new_with_fd_list:
237 * @fd_list: a #GUnixFDList
239 * Creates a new #GUnixFDMessage containing @list.
241 * Returns: a new #GUnixFDMessage
245 GSocketControlMessage *
246 g_unix_fd_message_new_with_fd_list (GUnixFDList *fd_list)
248 return g_object_new (G_TYPE_UNIX_FD_MESSAGE,
254 * g_unix_fd_message_steal_fds:
255 * @message: a #GUnixFDMessage
256 * @length: pointer to the length of the returned array, or %NULL
258 * Returns the array of file descriptors that is contained in this
261 * After this call, the descriptors are no longer contained in
262 * @message. Further calls will return an empty list (unless more
263 * descriptors have been added).
265 * The return result of this function must be freed with g_free().
266 * The caller is also responsible for closing all of the file
269 * If @length is non-%NULL then it is set to the number of file
270 * descriptors in the returned array. The returned array is also
271 * terminated with -1.
273 * This function never returns %NULL. In case there are no file
274 * descriptors contained in @message, an empty array is returned.
276 * Returns: an array of file descriptors
281 g_unix_fd_message_steal_fds (GUnixFDMessage *message,
284 g_return_val_if_fail (G_UNIX_FD_MESSAGE (message), FALSE);
286 return g_unix_fd_list_steal_fds (message->priv->list, length);
290 * g_unix_fd_message_append_fd:
291 * @message: a #GUnixFDMessage
292 * @fd: a valid open file descriptor
293 * @error: a #GError pointer
295 * Adds a file descriptor to @message.
297 * The file descriptor is duplicated using dup(). You keep your copy
298 * of the descriptor and the copy contained in @message will be closed
299 * when @message is finalized.
301 * A possible cause of failure is exceeding the per-process or
302 * system-wide file descriptor limit.
304 * Returns: %TRUE in case of success, else %FALSE (and @error is set)
309 g_unix_fd_message_append_fd (GUnixFDMessage *message,
313 g_return_val_if_fail (G_UNIX_FD_MESSAGE (message), FALSE);
315 return g_unix_fd_list_append (message->priv->list, fd, error) > 0;
318 #define __G_UNIX_FD_MESSAGE_C__
319 #include "gioaliasdef.c"