toolkit/system/dbus/nsDBusService.cpp

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   4 /* ***** BEGIN LICENSE BLOCK *****
   5  * Version: NPL 1.1/GPL 2.0/LGPL 2.1
   6  *
   7  *
   8  * The contents of this file are subject to the Mozilla Public
   9  * License Version 1.1 (the "License"); you may not use this file
  10  * except in compliance with the License. You may obtain a copy of
  11  * the License at http://www.mozilla.org/MPL/
  12  *
  13  * Software distributed under the License is distributed on an "AS
  14  * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
  15  * implied. See the License for the specific language governing
  16  * rights and limitations under the License.
  17  *
  18  * The Original Code is Novell code.
  19  *
  20  * The Initial Developer of the Original Code is Novell, Inc.
  21  * Portions created by the Initial Developer are Copyright (C) 2006
  22  * the Initial Developer. All Rights Reserved.
  23  *
  24  * Original Author: Robert O'Callahan (rocallahan@novell.com)
  25  *
  26  * Contributor(s):
  27  *
  28  * Alternatively, the contents of this file may be used under the terms of
  29  * either the GNU General Public License Version 2 or later (the "GPL"), or
  30  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  31  * in which case the provisions of the GPL or the LGPL are applicable instead
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  36  * and other provisions required by the GPL or the LGPL. If you do not delete
  37  * the provisions above, a recipient may use your version of this file under
  38  * the terms of any one of the NPL, the GPL or the LGPL.
  39  *
  40  * ***** END LICENSE BLOCK ***** */
  41
  42 #include "nsDBusService.h"
  43 #include "nsComponentManagerUtils.h"
  44
  45 #include <glib.h>
  46 #include <dbus/dbus-glib-lowlevel.h>
  47 #include <dbus/dbus-glib.h>
  48
  49 nsDBusService::nsDBusService() {
  50   mConnection = nsnull;
  51   mSingleClient = nsnull;
  52 }
  53
  54 nsDBusService::~nsDBusService() {
  55   NS_ASSERTION(!mSingleClient, "Client failed to unregister");
  56   DropConnection();
  57   if (mReconnectTimer) {
  58     mReconnectTimer->Cancel();
  59   }
  60   gSingleton = nsnull;
  61 }
  62
  63 NS_IMPL_ISUPPORTS1(nsDBusService, nsDBusService)
  64 NS_DEFINE_STATIC_IID_ACCESSOR(nsDBusService, NS_DBUS_IID)
  65
  66 nsDBusService* nsDBusService::gSingleton = nsnull;
  67
  68 already_AddRefed<nsDBusService>
  69 nsDBusService::Get() {
  70   if (!gSingleton) {
  71     gSingleton = new nsDBusService();
  72   }
  73   NS_IF_ADDREF(gSingleton);
  74   return gSingleton;
  75 }
  76
  77 nsresult
  78 nsDBusService::AddClient(DBusClient* client) {
  79   NS_ASSERTION(!mSingleClient, "Only one client supported right now");
  80   mSingleClient = client;
  81   nsresult rv = CreateConnection();
  82   if (NS_FAILED(rv)) {
  83     mSingleClient = nsnull;
  84   }
  85   return rv;
  86 }
  87
  88 void
  89 nsDBusService::RemoveClient(DBusClient* client) {
  90   NS_ASSERTION(mSingleClient == client, "Removing wrong client");
  91   mSingleClient = nsnull;
  92 }
  93
  94 DBusPendingCall*
  95 nsDBusService::SendWithReply(DBusClient* client, DBusMessage* message) {
  96   DBusPendingCall* reply = nsnull;
  97   if (mConnection) {
  98     if (!dbus_connection_send_with_reply(mConnection, message, &reply, -1)) {
  99       reply = nsnull;
 100     }
 101   }
 102   dbus_message_unref(message);
 103   return reply;
 104 }
 105
 106 PRBool nsDBusService::HandleMessage(DBusMessage* message) {
 107   if (dbus_message_is_signal(message, DBUS_INTERFACE_LOCAL,
 108                             "Disconnected")) {
 109     HandleDBusDisconnect();
 110     return PR_FALSE;
 111   }
 112
 113   return mSingleClient && mSingleClient->HandleMessage(message);
 114 }
 115
 116 static DBusHandlerResult dbus_filter(DBusConnection* connection,
 117                                      DBusMessage* message,
 118                                      void* user_data) {
 119   return static_cast<nsDBusService*>(user_data)->HandleMessage(message)
 120     ? DBUS_HANDLER_RESULT_HANDLED : DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 121 }
 122
 123 void nsDBusService::DoTimerCallback(nsITimer *aTimer) {
 124   if (aTimer == mReconnectTimer.get()) {
 125     nsresult rv = CreateConnection();
 126     if (NS_SUCCEEDED(rv)) {
 127       mReconnectTimer->Cancel();
 128       mReconnectTimer = nsnull;
 129     }
 130   }
 131 }
 132
 133 static void TimerCallback(nsITimer *aTimer, void *aClosure) {
 134   static_cast<nsDBusService*>(aClosure)->DoTimerCallback(aTimer);
 135 }
 136
 137 void nsDBusService::DropConnection() {
 138   if (mConnection) {
 139     if (mSingleClient) {
 140       mSingleClient->UnregisterWithConnection(mConnection);
 141     }
 142     dbus_connection_unref(mConnection);
 143     mConnection = nsnull;
 144   }
 145 }
 146
 147 void nsDBusService::HandleDBusDisconnect() {
 148   DropConnection();
 149
 150   nsresult rv;
 151   mReconnectTimer = do_CreateInstance("@mozilla.org/timer;1", &rv);
 152   if (NS_FAILED(rv))
 153     return;
 154   rv = mReconnectTimer->InitWithFuncCallback(TimerCallback, this,
 155                                              5000, nsITimer::TYPE_REPEATING_SLACK);
 156   if (NS_FAILED(rv)) {
 157     mReconnectTimer = nsnull;
 158     return;
 159   }
 160 }
 161
 162 nsresult nsDBusService::CreateConnection() {
 163   mConnection = dbus_bus_get(DBUS_BUS_SYSTEM, NULL);
 164   if (!mConnection)
 165     return NS_ERROR_FAILURE;
 166
 167   dbus_connection_set_exit_on_disconnect(mConnection, PR_FALSE);
 168   dbus_connection_setup_with_g_main(mConnection, NULL);
 169
 170   if (!dbus_connection_add_filter(mConnection, dbus_filter, this, NULL))
 171     return NS_ERROR_FAILURE;
 172
 173   mSingleClient->RegisterWithConnection(mConnection);
 174   return NS_OK;
 175 }