Index: chrome/browser/sync/glue/bookmark_model_worker.cc |
=================================================================== |
--- chrome/browser/sync/glue/bookmark_model_worker.cc (revision 0) |
+++ chrome/browser/sync/glue/bookmark_model_worker.cc (revision 0) |
@@ -0,0 +1,114 @@ |
+// Copyright (c) 2006-2008 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. |
+ |
+#ifdef CHROME_PERSONALIZATION |
+ |
+#include "chrome/browser/sync/glue/bookmark_model_worker.h" |
+ |
+#include "base/message_loop.h" |
+#include "base/waitable_event.h" |
+ |
+namespace browser_sync { |
+ |
+void BookmarkModelWorker::CallDoWorkFromModelSafeThreadAndWait( |
+ ModelSafeWorkerInterface::Visitor* visitor) { |
+ // It is possible this gets called when we are in the STOPPING state, because |
+ // the UI loop has initiated shutdown but the syncer hasn't got the memo yet. |
+ // This is fine, the work will get scheduled and run normally or run by our |
+ // code handling this case in Stop(). |
+ DCHECK_NE(state_, STOPPED); |
+ if (state_ == STOPPED) |
+ return; |
+ if (MessageLoop::current() == bookmark_model_loop_) { |
+ DLOG(WARNING) << "CallDoWorkFromModelSafeThreadAndWait called from " |
+ << "bookmark_model_loop_. Probably a nested invocation?"; |
+ visitor->DoWork(); |
+ return; |
+ } |
+ |
+ // Create an unsignaled event to wait on. |
+ base::WaitableEvent work_done(false, false); |
+ { |
+ // We lock only to avoid PostTask'ing a NULL pending_work_ (because it |
+ // could get Run() in Stop() and call OnTaskCompleted before we post). |
+ // The task is owned by the message loop as per usual. |
+ AutoLock lock(pending_work_lock_); |
+ DCHECK(!pending_work_); |
+ pending_work_ = new CallDoWorkAndSignalTask(visitor, &work_done, this); |
+ bookmark_model_loop_->PostTask(FROM_HERE, pending_work_); |
+ } |
+ syncapi_event_.Signal(); // Notify that the syncapi produced work for us. |
+ work_done.Wait(); |
+} |
+ |
+BookmarkModelWorker::~BookmarkModelWorker() { |
+ DCHECK_EQ(state_, STOPPED); |
+} |
+ |
+void BookmarkModelWorker::OnSyncerShutdownComplete() { |
+ // The SyncerThread has terminated and we are no longer needed by syncapi. |
+ // The UI loop initiated shutdown and is (or will be) waiting in Stop(). |
+ // We could either be WORKING or RUNNING_MANUAL_SHUTDOWN_PUMP, depending |
+ // on where we timeslice the UI thread in Stop; but we can't be STOPPED, |
+ // because that would imply NotifySyncapiShutdownComplete already signaled. |
+ DCHECK_NE(state_, STOPPED); |
+ |
+ syncapi_has_shutdown_ = true; |
+ syncapi_event_.Signal(); |
+} |
+ |
+void BookmarkModelWorker::Stop() { |
+ DCHECK_EQ(MessageLoop::current(), bookmark_model_loop_); |
+ DCHECK_EQ(state_, WORKING); |
+ |
+ // We're on our own now, the beloved UI MessageLoop is no longer running. |
+ // Any tasks scheduled or to be scheduled on the UI MessageLoop will not run. |
+ state_ = RUNNING_MANUAL_SHUTDOWN_PUMP; |
+ |
+ // Drain any final task manually until the SyncerThread tells us it has |
+ // totally finished. Note we use a 'while' loop and not 'if'. The main subtle |
+ // reason for this is that syncapi_event could be signaled the first time we |
+ // come through due to an old CallDoWork call, and we need to keep looping |
+ // until the SyncerThread either calls it again or tells us it is done. There |
+ // should only ever be 0 or 1 tasks Run() here, however. |
+ while (!syncapi_has_shutdown_) { |
+ { |
+ AutoLock lock(pending_work_lock_); |
+ if (pending_work_) |
+ pending_work_->Run(); |
+ } |
+ syncapi_event_.Wait(); // Signaled either by new task, or SyncerThread |
+ // termination. |
+ } |
+ |
+ state_ = STOPPED; |
+} |
+ |
+void BookmarkModelWorker::CallDoWorkAndSignalTask::Run() { |
+ if (!visitor_) { |
+ // This can happen during tests or cases where there are more than just the |
+ // default BookmarkModelWorker in existence and it gets destroyed before |
+ // the main UI loop has terminated. There is no easy way to assert the |
+ // loop is running / not running at the moment, so we just provide cancel |
+ // semantics here and short-circuit. |
+ // TODO(timsteele): Maybe we should have the message loop destruction |
+ // observer fire when the loop has ended, just a bit before it |
+ // actually gets destroyed. |
+ return; |
+ } |
+ visitor_->DoWork(); |
+ |
+ // Sever ties with visitor_ to allow the sanity-checking above that we don't |
+ // get run twice. |
+ visitor_ = NULL; |
+ |
+ // Notify the BookmarkModelWorker that scheduled us that we have run |
+ // successfully. |
+ scheduler_->OnTaskCompleted(); |
+ work_done_->Signal(); // Unblock the syncer thread that scheduled us. |
+} |
+ |
+} // namespace browser_sync |
+ |
+#endif // CHROME_PERSONALIZATION |
Property changes on: chrome\browser\sync\glue\bookmark_model_worker.cc |
___________________________________________________________________ |
Added: svn:eol-style |
+ LF |