gdata: Convert public synchronous functions in GDataFileSystem to asynchronous.

chrome/browser/chromeos/gdata/gdata_file_system.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/gdata/gdata_file_system.h"
 
 #include <errno.h>
 #include <sys/stat.h>
 
 #include <set>
@@ skipping 875 matching lines @@
 // Returns callback which runs the given |callback| on the current thread.
 template<typename CallbackType>
 CallbackType CreateRelayCallback(const CallbackType& callback) {
   return base::Bind(&RelayCallback<CallbackType>::Run,
                     base::MessageLoopProxy::current(),
                     callback);
 }
 
 }  // namespace
 
-// GDataFileProperties struct implementation.
-
-GDataFileProperties::GDataFileProperties() : is_hosted_document(false) {
-}
-
-GDataFileProperties::~GDataFileProperties() {
-}
-
 // GDataFileSystem::GetDocumentsParams struct implementation.
 
 GDataFileSystem::GetDocumentsParams::GetDocumentsParams(
     int start_changestamp,
     int root_feed_changestamp,
     std::vector<DocumentFeed*>* feed_list,
     bool should_fetch_multiple_feeds,
     const FilePath& search_file_path,
     const std::string& search_query,
     const std::string& directory_resource_id,
@@ skipping 1101 matching lines @@
                      callback)));
 }
 
 void GDataFileSystem::GetFileByPath(
     const FilePath& file_path,
     const GetFileCallback& get_file_callback,
     const GetDownloadDataCallback& get_download_data_callback) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI) ||
          BrowserThread::CurrentlyOn(BrowserThread::IO));
   RunTaskOnUIThread(
-      base::Bind(&GDataFileSystem::GetFileByPathOnUIThread,
+      base::Bind(&GDataFileSystem::GetFileInfoByPathAsync,

[satorux1, 2012/06/07 22:47:17]

Can you keep the function as before? We use this pattern (call FooOnUI from Foo)
in other functions. I'd like to keep consistency. 

[hshi1, 2012/06/08 00:22:05]

Done.

Note that I have to create a common shared function called
"GetResolvedFileByPath" (suggestions welcome for a proper name). This is shared
by OnGetFileInfoCompleteForGetFileByPath and OnGetFileInfoCompleteForOpenFile.
Previously OnGetFileInfoCompleteForOpenFile just calls GetFileByPathOnUIThread()
but after this refactoring I need to invent some new function names :-)

                  ui_weak_ptr_,
                  file_path,
-                 CreateRelayCallback(get_file_callback),
-                 CreateRelayCallback(get_download_data_callback)));
+                 base::Bind(
+                     &GDataFileSystem::OnGetFileInfoCompleteForGetFileByPath,
+                     ui_weak_ptr_,
+                     file_path,
+                     CreateRelayCallback(get_file_callback),
+                     CreateRelayCallback(get_download_data_callback))));
+}
+
+void GDataFileSystem::OnGetFileInfoCompleteForGetFileByPath(
+    const FilePath& file_path,
+    const GetFileCallback& get_file_callback,
+    const GetDownloadDataCallback& get_download_data_callback,
+    base::PlatformFileError error,
+    scoped_ptr<GDataFileProto> file_info) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+
+  DCHECK(!file_info->gdata_entry().resource_id().empty());
+  GetFileByPathOnUIThread(file_path,
+                          get_file_callback,
+                          get_download_data_callback,
+                          error,
+                          file_info.get());
 }
 
 void GDataFileSystem::GetFileByPathOnUIThread(
     const FilePath& file_path,
     const GetFileCallback& get_file_callback,
-    const GetDownloadDataCallback& get_download_data_callback) {
+    const GetDownloadDataCallback& get_download_data_callback,
+    base::PlatformFileError error,
+    const GDataFileProto* file_proto) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));

[satorux1, 2012/06/07 22:47:17]

DCHECK(file_proto);

[hshi1, 2012/06/08 00:22:05]

Actually file_proto can be NULL. It is checked in the line below: if error != OK
or !file_proto then make callback with ERROR_NOT_FOUND error.

 
-  GDataFileProperties file_properties;
-  if (!GetFileInfoByPath(file_path, &file_properties)) {
+  if (error != base::PLATFORM_FILE_OK || !file_proto) {
     if (!get_file_callback.is_null()) {
       MessageLoop::current()->PostTask(
           FROM_HERE,
           base::Bind(get_file_callback,
                      base::PLATFORM_FILE_ERROR_NOT_FOUND,
                      FilePath(),
                      std::string(),
                      REGULAR_FILE));
     }
     return;
   }
 
   // For a hosted document, we create a special JSON file to represent the
   // document instead of fetching the document content in one of the exported
   // formats. The JSON file contains the edit URL and resource ID of the
   // document.
-  if (file_properties.is_hosted_document) {
+  if (file_proto->is_hosted_document()) {
     base::PlatformFileError* error =
         new base::PlatformFileError(base::PLATFORM_FILE_OK);
     FilePath* temp_file_path = new FilePath;
     std::string* mime_type = new std::string;
     GDataFileType* file_type = new GDataFileType(REGULAR_FILE);
     PostBlockingPoolSequencedTaskAndReply(
         FROM_HERE,
         base::Bind(&CreateDocumentJsonFileOnIOThreadPool,
                    GetCacheDirectoryPath(
                        GDataCache::CACHE_TYPE_TMP_DOCUMENTS),
-                   file_properties.alternate_url,
-                   file_properties.resource_id,
+                   GURL(file_proto->alternate_url()),
+                   file_proto->gdata_entry().resource_id(),
                    error,
                    temp_file_path,
                    mime_type,
                    file_type),
         base::Bind(&RunGetFileCallbackHelper,
                    get_file_callback,
                    base::Owned(error),
                    base::Owned(temp_file_path),
                    base::Owned(mime_type),
                    base::Owned(file_type)));
     return;
   }
 
   // Returns absolute path of the file if it were cached or to be cached.
-  FilePath local_tmp_path = GetCacheFilePath(file_properties.resource_id,
-                                             file_properties.file_md5,
-                                             GDataCache::CACHE_TYPE_TMP,
-                                             CACHED_FILE_FROM_SERVER);
+  FilePath local_tmp_path = GetCacheFilePath(
+      file_proto->gdata_entry().resource_id(),
+      file_proto->file_md5(),
+      GDataCache::CACHE_TYPE_TMP,
+      CACHED_FILE_FROM_SERVER);
   GetFileFromCacheByResourceIdAndMd5(
-      file_properties.resource_id,
-      file_properties.file_md5,
+      file_proto->gdata_entry().resource_id(),
+      file_proto->file_md5(),
       base::Bind(
           &GDataFileSystem::OnGetFileFromCache,
           ui_weak_ptr_,
           GetFileFromCacheParams(file_path,
                                  local_tmp_path,
-                                 file_properties.content_url,
-                                 file_properties.resource_id,
-                                 file_properties.file_md5,
-                                 file_properties.mime_type,
+                                 GURL(file_proto->gdata_entry().content_url()),
+                                 file_proto->gdata_entry().resource_id(),
+                                 file_proto->file_md5(),
+                                 file_proto->content_mime_type(),
                                  get_file_callback,
                                  get_download_data_callback)));
 }
 
 void GDataFileSystem::GetFileByResourceId(
     const std::string& resource_id,
     const GetFileCallback& get_file_callback,
     const GetDownloadDataCallback& get_download_data_callback) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI) ||
          BrowserThread::CurrentlyOn(BrowserThread::IO));
@@ skipping 438 matching lines @@
     directory->AddEntry(entry.release());
   }
 
   // Note that there may be no change in the directory, but it's expensive to
   // check if the new metadata matches the existing one, so we just always
   // notify that the directory is changed.
   NotifyDirectoryChanged(directory_path);
   DVLOG(1) << "Directory refreshed: " << directory_path.value();
 }
 
-bool GDataFileSystem::GetFileInfoByPath(
-    const FilePath& file_path, GDataFileProperties* properties) {
-  DCHECK(properties);
-  base::AutoLock lock(lock_);
-  GDataEntry* entry = GetGDataEntryByPath(file_path);
-  if (!entry)
-    return false;
-
-  properties->file_info = entry->file_info();
-  properties->resource_id = entry->resource_id();
-
-  GDataFile* regular_file = entry->AsGDataFile();
-  if (regular_file) {
-    properties->file_md5 = regular_file->file_md5();
-    properties->mime_type = regular_file->content_mime_type();
-    properties->content_url = regular_file->content_url();
-    properties->alternate_url = regular_file->alternate_url();
-    properties->is_hosted_document = regular_file->is_hosted_document();
-  }
-  return true;
-}
-
 GDataEntry* GDataFileSystem::GetGDataEntryByPath(
     const FilePath& file_path) {
   lock_.AssertAcquired();
   // Find directory element within the cached file system snapshot.
   GDataEntry* entry = NULL;
   root_->FindEntryByPath(file_path, base::Bind(&ReadOnlyFindEntryCallback,
                                                &entry));
   return entry;
 }
 
@@ skipping 2551 matching lines @@
     }
   }
 
   if (error != base::PLATFORM_FILE_OK) {
     if (!callback.is_null())
       callback.Run(error, FilePath());
     return;
   }
 
   DCHECK(!file_info->gdata_entry().resource_id().empty());
-
-  // TODO(kinaba): once it is cleaned up (crbug/127048), remove the indirection.
-  // Do not call GetFileByPathOnUIThread() directly for avoiding deadlock.
-  // The current method is called as a callback from GetFileInfoByPathAsync(),
-  // which is under the lock taken.
-  base::MessageLoopProxy::current()->PostTask(
-      FROM_HERE,
-      base::Bind(&GDataFileSystem::GetFileByPathOnUIThread,
+  GetFileByPathOnUIThread(
+      file_path,
+      base::Bind(&GDataFileSystem::OnGetFileCompleteForOpenFile,
                  ui_weak_ptr_,
-                 file_path,
-                 base::Bind(&GDataFileSystem::OnGetFileCompleteForOpenFile,
-                            ui_weak_ptr_,
-                            callback,
-                            base::Passed(&file_info)),
-                 GetDownloadDataCallback()));
+                 callback,
+                 base::Passed(&file_info)),
+      GetDownloadDataCallback(),
+      error,
+      file_info.get());
 }
 
 void GDataFileSystem::OnGetFileCompleteForOpenFile(
     const OpenFileCallback& callback,
     scoped_ptr<GDataFileProto> file_info,
     base::PlatformFileError error,
     const FilePath& file_path,
     const std::string& mime_type,
     GDataFileType file_type) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
@@ skipping 68 matching lines @@
       callback.Run(error);
     return;
   }
 
   DCHECK(!file_info->gdata_entry().resource_id().empty());
 
   // TODO(benchan,kinaba): Call ClearDirtyInCache instead of CommitDirtyInCache
   // if the file has not been modified. Come up with a way to detect the
   // intactness effectively, or provide a method for user to declare it when
   // calling CloseFile().
-
-  // TODO(kinaba): once it is cleaned up (crbug/127048), remove the indirection.
-  // Do not call CommitDirtyInCache() directly for avoiding deadlock.
-  // The current method is called as a callback from GetFileInfoByPathAsync(),
-  // which is under the lock taken.
-  base::MessageLoopProxy::current()->PostTask(
-      FROM_HERE,
+  CommitDirtyInCache(
+      file_info->gdata_entry().resource_id(),
+      file_info->file_md5(),
       base::Bind(
-          &GDataFileSystem::CommitDirtyInCache,
+          &GDataFileSystem::OnCommitDirtyInCacheCompleteForCloseFile,
           ui_weak_ptr_,
-          file_info->gdata_entry().resource_id(),
-          file_info->file_md5(),
-          base::Bind(&GDataFileSystem::OnCommitDirtyInCacheCompleteForCloseFile,
-                     ui_weak_ptr_,
-                     callback)));
+          callback));
 }
 
 void GDataFileSystem::OnCommitDirtyInCacheCompleteForCloseFile(
     const CloseFileCallback& callback,
     base::PlatformFileError error,
     const std::string& resource_id,
     const std::string& md5) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
   if (!callback.is_null())
     callback.Run(error);
 }
 
 }  // namespace gdata