src/greeter-socket.c

   1 /*
   2  * Copyright (C) 2010-2016 Canonical Ltd.
   3  *
   4  * This program is free software: you can redistribute it and/or modify it under
   5  * the terms of the GNU General Public License as published by the Free Software
   6  * Foundation, either version 3 of the License, or (at your option) any later
   7  * version. See http://www.gnu.org/copyleft/gpl.html the full text of the
   8  * license.
   9  */
  10
  11 #include <config.h>
  12
  13 #include <errno.h>
  14 #include <sys/stat.h>
  15 #include <gio/gio.h>
  16 #include <gio/gunixsocketaddress.h>
  17
  18 #include "greeter-socket.h"
  19
  20 enum {
  21     CREATE_GREETER,
  22     LAST_SIGNAL
  23 };
  24 static guint signals[LAST_SIGNAL] = { 0 };
  25
  26 struct GreeterSocketPrivate
  27 {
  28     /* Path of socket to use */
  29     gchar *path;
  30
  31     /* Listening UNIX socket */
  32     GSocket *socket;
  33
  34     /* Source for listening for connections */
  35     GSource *source;
  36
  37     /* Socket to greeter */
  38     GSocket *greeter_socket;
  39
  40     /* Greeter connected on this socket */
  41     Greeter *greeter;
  42 };
  43
  44 G_DEFINE_TYPE (GreeterSocket, greeter_socket, G_TYPE_OBJECT);
  45
  46 GreeterSocket *
  47 greeter_socket_new (const gchar *path)
  48 {
  49     GreeterSocket *socket;
  50
  51     socket = g_object_new (GREETER_SOCKET_TYPE, NULL);
  52     socket->priv->path = g_strdup (path);
  53
  54     return socket;
  55 }
  56
  57 static void
  58 greeter_disconnected_cb (Greeter *greeter, GreeterSocket *socket)
  59 {
  60     if (greeter == socket->priv->greeter)
  61     {
  62         g_clear_object (&socket->priv->greeter);
  63         g_clear_object (&socket->priv->greeter_socket);
  64     }
  65 }
  66
  67 static gboolean
  68 greeter_connect_cb (GSocket *s, GIOCondition condition, GreeterSocket *socket)
  69 {
  70     GSocket *new_socket;
  71     GError *error = NULL;
  72
  73     new_socket = g_socket_accept (socket->priv->socket, NULL, &error);
  74     if (error)
  75         g_warning ("Failed to accept greeter connection: %s", error->message);
  76     g_clear_error (&error);
  77     if (!new_socket)
  78         return G_SOURCE_CONTINUE;
  79
  80     /* Greeter already connected */
  81     if (socket->priv->greeter)
  82     {
  83         g_socket_close (new_socket, NULL);
  84         g_object_unref (new_socket);
  85         return G_SOURCE_CONTINUE;
  86     }
  87
  88     socket->priv->greeter_socket = new_socket;
  89     g_signal_emit (socket, signals[CREATE_GREETER], 0, &socket->priv->greeter);
  90     g_signal_connect (socket->priv->greeter, GREETER_SIGNAL_DISCONNECTED, G_CALLBACK (greeter_disconnected_cb), socket);
  91     greeter_set_file_descriptors (socket->priv->greeter, g_socket_get_fd (new_socket), g_socket_get_fd (new_socket));
  92
  93     return G_SOURCE_CONTINUE;
  94 }
  95
  96 gboolean
  97 greeter_socket_start (GreeterSocket *socket, GError **error)
  98 {
  99     GSocketAddress *address;
 100     gboolean result;
 101
 102     g_return_val_if_fail (socket != NULL, FALSE);
 103     g_return_val_if_fail (socket->priv->socket == NULL, FALSE);
 104
 105     socket->priv->socket = g_socket_new (G_SOCKET_FAMILY_UNIX, G_SOCKET_TYPE_STREAM, G_SOCKET_PROTOCOL_DEFAULT, error);
 106     if (!socket->priv->socket)
 107         return FALSE;
 108
 109     unlink (socket->priv->path);
 110     address = g_unix_socket_address_new (socket->priv->path);
 111     result = g_socket_bind (socket->priv->socket, address, FALSE, error);
 112     g_object_unref (address);
 113     if (!result)
 114         return FALSE;
 115     if (!g_socket_listen (socket->priv->socket, error))
 116         return FALSE;
 117
 118     socket->priv->source = g_socket_create_source (socket->priv->socket, G_IO_IN, NULL);
 119     g_source_set_callback (socket->priv->source, (GSourceFunc) greeter_connect_cb, socket, NULL);
 120     g_source_attach (socket->priv->source, NULL);
 121
 122     /* Allow to be written to */
 123     if (chmod (socket->priv->path, S_IRWXU | S_IRWXG | S_IRWXO) < 0)
 124     {
 125         g_set_error (error,
 126                      G_FILE_ERROR,
 127                      g_file_error_from_errno (errno),
 128                      "Failed to set permissions on greeter socket %s: %s",
 129                      socket->priv->path,
 130                      g_strerror (errno));
 131         return FALSE;
 132     }
 133
 134     return TRUE;
 135 }
 136
 137 static void
 138 greeter_socket_init (GreeterSocket *socket)
 139 {
 140     socket->priv = G_TYPE_INSTANCE_GET_PRIVATE (socket, GREETER_SOCKET_TYPE, GreeterSocketPrivate);
 141 }
 142
 143 static void
 144 greeter_socket_finalize (GObject *object)
 145 {
 146     GreeterSocket *self = GREETER_SOCKET (object);
 147
 148     if (self->priv->path)
 149         unlink (self->priv->path);
 150     g_free (self->priv->path);
 151     g_clear_object (&self->priv->socket);
 152     g_clear_object (&self->priv->source);
 153     g_clear_object (&self->priv->greeter_socket);
 154     g_clear_object (&self->priv->greeter);
 155
 156     G_OBJECT_CLASS (greeter_socket_parent_class)->finalize (object);
 157 }
 158
 159 static void
 160 greeter_socket_class_init (GreeterSocketClass *klass)
 161 {
 162     GObjectClass *object_class = G_OBJECT_CLASS (klass);
 163
 164     object_class->finalize = greeter_socket_finalize;
 165
 166     signals[CREATE_GREETER] =
 167         g_signal_new (GREETER_SOCKET_SIGNAL_CREATE_GREETER,
 168                       G_TYPE_FROM_CLASS (klass),
 169                       G_SIGNAL_RUN_LAST,
 170                       G_STRUCT_OFFSET (GreeterSocketClass, create_greeter),
 171                       g_signal_accumulator_first_wins,
 172                       NULL,
 173                       NULL,
 174                       GREETER_TYPE, 0);
 175
 176     g_type_class_add_private (klass, sizeof (GreeterSocketPrivate));
 177 }