gdata: Implement periodic file system update checks.

chrome/browser/chromeos/extensions/file_browser_event_router.cc

 // Copyright (c) 2012 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/browser/chromeos/extensions/file_browser_event_router.h"
 
 #include "base/bind.h"
 #include "base/json/json_writer.h"
 #include "base/message_loop.h"
 #include "base/stl_util.h"
@@ skipping 69 matching lines @@
     default:
       NOTREACHED();
   }
   return "";
 }
 
 FileBrowserEventRouter::FileBrowserEventRouter(
     Profile* profile)
     : delegate_(new FileBrowserEventRouter::FileWatcherDelegate(this)),
       notifications_(new FileBrowserNotifications(profile)),
-      profile_(profile) {
+      profile_(profile),
+      num_remote_update_requests_(0) {
 }
 
 FileBrowserEventRouter::~FileBrowserEventRouter() {
 }
 
 void FileBrowserEventRouter::ShutdownOnUIThread() {
   DCHECK(file_watchers_.empty());
   STLDeleteValues(&file_watchers_);
   if (!profile_) {
     NOTREACHED();
@@ skipping 42 matching lines @@
     const std::string& extension_id) {
   base::AutoLock lock(lock_);
   FilePath watch_path = local_path;
   bool is_remote_watch = false;
   // Tweak watch path for remote sources - we need to drop leading /special
   // directory from there in order to be able to pair these events with
   // their change notifications.
   if (gdata::util::GetSpecialRemoteRootPath().IsParent(watch_path)) {
     watch_path = gdata::util::ExtractGDataPath(watch_path);
     is_remote_watch = true;
+    BrowserThread::PostTask(
+        BrowserThread::UI, FROM_HERE,
+        base::Bind(&FileBrowserEventRouter::HandleRemoteUpdateRequestOnUIThread,
+                   this, true));
   }
 
   WatcherMap::iterator iter = file_watchers_.find(watch_path);
   if (iter == file_watchers_.end()) {
     scoped_ptr<FileWatcherExtensions>
         watch(new FileWatcherExtensions(virtual_path,
                                         extension_id,
                                         is_remote_watch));
 
     if (watch->Watch(watch_path, delegate_.get()))
       file_watchers_[watch_path] = watch.release();
     else
       return false;
   } else {
     iter->second->AddExtension(extension_id);
   }
   return true;
 }
 
 void FileBrowserEventRouter::RemoveFileWatch(
     const FilePath& local_path,
     const std::string& extension_id) {
   base::AutoLock lock(lock_);
   FilePath watch_path = local_path;
   // Tweak watch path for remote sources - we need to drop leading /special
   // directory from there in order to be able to pair these events with
   // their change notifications.
   if (gdata::util::GetSpecialRemoteRootPath().IsParent(watch_path)) {
     watch_path = gdata::util::ExtractGDataPath(watch_path);
+    BrowserThread::PostTask(
+        BrowserThread::UI, FROM_HERE,
+        base::Bind(&FileBrowserEventRouter::HandleRemoteUpdateRequestOnUIThread,

[zel, 2012/05/03 21:21:10]

why are you routing this to another thread? this function should be already
running on UI thread - no? 

+                   this, false));
   }
   WatcherMap::iterator iter = file_watchers_.find(watch_path);
   if (iter == file_watchers_.end())
     return;
   // Remove the renderer process for this watch.
   iter->second->RemoveExtension(extension_id);
   if (iter->second->GetRefCount() == 0) {
     delete iter->second;
     file_watchers_.erase(iter);
   }
 }
 
+void FileBrowserEventRouter::HandleRemoteUpdateRequestOnUIThread(bool start) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+
+  gdata::GDataFileSystem* file_system = GetRemoteFileSystem();
+  DCHECK(file_system);
+
+  if (start) {
+    file_system->CheckForUpdates();
+    if (num_remote_update_requests_ == 0)
+      file_system->StartUpdates();
+    ++num_remote_update_requests_;
+  } else {
+    DCHECK_LE(0, num_remote_update_requests_);
+    --num_remote_update_requests_;
+    if (num_remote_update_requests_ == 0)
+      file_system->StopUpdates();
+  }
+}
+
 void FileBrowserEventRouter::DiskChanged(
     DiskMountManagerEventType event,
     const DiskMountManager::Disk* disk) {
   // Disregard hidden devices.
   if (disk->is_hidden())
     return;
   if (event == chromeos::disks::MOUNT_DISK_ADDED) {
     OnDiskAdded(disk);
   } else if (event == chromeos::disks::MOUNT_DISK_REMOVED) {
     OnDiskRemoved(disk);
@@ skipping 44 matching lines @@
      notifications_->ManageNotificationsOnMountCompleted(
         disk->system_path_prefix(), disk->drive_label(), disk->is_parent(),
         error_code == chromeos::MOUNT_ERROR_NONE,
         error_code == chromeos::MOUNT_ERROR_UNSUPORTED_FILESYSTEM);
   } else if (mount_info.mount_type == chromeos::MOUNT_TYPE_ARCHIVE) {
     // Clear the "mounted" state for archive files in gdata cache
     // when mounting failed or unmounting succeeded.
     if ((event_type == DiskMountManager::MOUNTING) !=
         (error_code == chromeos::MOUNT_ERROR_NONE)) {
       FilePath source_path(mount_info.source_path);
-      gdata::GDataSystemService* system_service =
-          gdata::GDataSystemServiceFactory::GetForProfile(profile_);
-      gdata::GDataFileSystem* file_system =
-          system_service ? system_service->file_system() : NULL;
+      gdata::GDataFileSystem* file_system = GetRemoteFileSystem();
       if (file_system && file_system->IsUnderGDataCacheDirectory(source_path))
         file_system->SetMountedState(source_path, false,
                                      gdata::SetMountedStateCallback());
     }
   }
 }
 
 void FileBrowserEventRouter::OnProgressUpdate(
     const std::vector<gdata::GDataOperationRegistry::ProgressStatus>& list) {
   scoped_ptr<ListValue> event_list(
@@ skipping 322 matching lines @@
 unsigned int
 FileBrowserEventRouter::FileWatcherExtensions::GetRefCount() const {
   return ref_count_;
 }
 
 const FilePath&
 FileBrowserEventRouter::FileWatcherExtensions::GetVirtualPath() const {
   return virtual_path_;
 }
 
+gdata::GDataFileSystem* FileBrowserEventRouter::GetRemoteFileSystem() const {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  gdata::GDataSystemService* system_service =
+      gdata::GDataSystemServiceFactory::GetForProfile(profile_);
+  return (system_service ? system_service->file_system() : NULL);
+}
+
 bool FileBrowserEventRouter::FileWatcherExtensions::Watch
     (const FilePath& path, FileWatcherDelegate* delegate) {
   if (is_remote_file_system_)
     return true;
 
   return file_watcher_->Watch(path, delegate);
 }
 
 // static
 scoped_refptr<FileBrowserEventRouter>
@@ skipping 22 matching lines @@
   return scoped_refptr<RefcountedProfileKeyedService>(
       new FileBrowserEventRouter(profile));
 }
 
 bool FileBrowserEventRouterFactory::ServiceHasOwnInstanceInIncognito() {
   // Explicitly and always allow this router in guest login mode.   see
   // chrome/browser/profiles/profile_keyed_base_factory.h comment
   // for the details.
   return true;
 }