Allow synchronous messages to be sent from threads other than the main thread...

chrome/common/db_message_filter.cc

-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/common/db_message_filter.h"
 
-#include "chrome/common/child_process.h"
 #include "chrome/common/render_messages.h"
 #include "third_party/WebKit/WebKit/chromium/public/WebDatabase.h"
 
-DBMessageFilter* DBMessageFilter::instance_ = NULL;
-
-DBMessageFilter::DBMessageFilter()
-    : io_thread_message_loop_(ChildProcess::current()->io_message_loop()),
-      channel_(NULL),
-      shutdown_event_(ChildProcess::current()->GetShutDownEvent()),
-      messages_awaiting_replies_(new IDMap<DBMessageState>()),
-      unique_id_generator_(new base::AtomicSequenceNumber()) {
-  DCHECK(!instance_);
-  instance_ = this;
-}
-
-int DBMessageFilter::GetUniqueID() {
-  return unique_id_generator_->GetNext();
-}
-
-static void SendMessageOnIOThread(IPC::Message* message,
-                                  IPC::Channel* channel,
-                                  Lock* channel_lock) {
-  AutoLock channel_auto_lock(*channel_lock);
-  if (channel)
-    channel->Send(message);
-  else
-    delete message;
-}
-
-void DBMessageFilter::Send(IPC::Message* message) {
-  io_thread_message_loop_->PostTask(FROM_HERE,
-      NewRunnableFunction(SendMessageOnIOThread, message, channel_,
-                          &channel_lock_));
-}
-
-void DBMessageFilter::OnFilterAdded(IPC::Channel* channel) {
-  AutoLock channel_auto_lock(channel_lock_);
-  channel_ = channel;
-}
-
-void DBMessageFilter::OnChannelError() {
-  AutoLock channel_auto_lock(channel_lock_);
-  channel_ = NULL;
-}
-
-void DBMessageFilter::OnChannelClosing() {
-  AutoLock channel_auto_lock(channel_lock_);
-  channel_ = NULL;
+DBMessageFilter::DBMessageFilter() {
 }
 
 bool DBMessageFilter::OnMessageReceived(const IPC::Message& message) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(DBMessageFilter, message)
-    IPC_MESSAGE_HANDLER(ViewMsg_DatabaseOpenFileResponse,
-                        OnResponse<ViewMsg_DatabaseOpenFileResponse_Params>)
-    IPC_MESSAGE_HANDLER(ViewMsg_DatabaseDeleteFileResponse, OnResponse<int>)
-    IPC_MESSAGE_HANDLER(ViewMsg_DatabaseGetFileAttributesResponse,
-                        OnResponse<uint32>)
-    IPC_MESSAGE_HANDLER(ViewMsg_DatabaseGetFileSizeResponse, OnResponse<int64>)
     IPC_MESSAGE_HANDLER(ViewMsg_DatabaseUpdateSize, OnDatabaseUpdateSize)
     IPC_MESSAGE_HANDLER(ViewMsg_DatabaseCloseImmediately,
                         OnDatabaseCloseImmediately)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   return handled;
 }
 
 void DBMessageFilter::OnDatabaseUpdateSize(const string16& origin_identifier,
                                            const string16& database_name,
                                            int64 database_size,
                                            int64 space_available) {
   WebKit::WebDatabase::updateDatabaseSize(
       origin_identifier, database_name, database_size, space_available);
 }
 
 void DBMessageFilter::OnDatabaseCloseImmediately(
     const string16& origin_identifier,
     const string16& database_name) {
   WebKit::WebDatabase::closeDatabaseImmediately(
       origin_identifier, database_name);
 }