gdata: Convert public synchronous functions in GDataFileSystem to asynchronous.

chrome/browser/chromeos/gdata/gdata_file_system.cc

Index: chrome/browser/chromeos/gdata/gdata_file_system.cc
diff --git a/chrome/browser/chromeos/gdata/gdata_file_system.cc b/chrome/browser/chromeos/gdata/gdata_file_system.cc
index f320bc932fe25979e35596a4d3e3a262b54960e5..d4bc88fdfadcc8b377510a5a730c6a0bf0370331 100644
--- a/chrome/browser/chromeos/gdata/gdata_file_system.cc
+++ b/chrome/browser/chromeos/gdata/gdata_file_system.cc
@@ -893,14 +893,6 @@ CallbackType CreateRelayCallback(const CallbackType& callback) {
 
 }  // namespace
 
-// GDataFileProperties struct implementation.
-
-GDataFileProperties::GDataFileProperties() : is_hosted_document(false) {
-}
-
-GDataFileProperties::~GDataFileProperties() {
-}
-
 // GDataFileSystem::GetDocumentsParams struct implementation.
 
 GDataFileSystem::GetDocumentsParams::GetDocumentsParams(
@@ -2022,21 +2014,42 @@ void GDataFileSystem::GetFileByPath(
   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,
@@ -2053,7 +2066,7 @@ void GDataFileSystem::GetFileByPathOnUIThread(
   // 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;
@@ -2064,8 +2077,8 @@ void GDataFileSystem::GetFileByPathOnUIThread(
         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,
@@ -2080,22 +2093,23 @@ void GDataFileSystem::GetFileByPathOnUIThread(
   }
 
   // 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)));
 }
@@ -2554,28 +2568,6 @@ void GDataFileSystem::OnRequestDirectoryRefresh(
   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();
@@ -5147,21 +5139,15 @@ void GDataFileSystem::OnGetFileInfoCompleteForOpenFile(
   }
 
   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(
@@ -5250,21 +5236,13 @@ void GDataFileSystem::OnGetFileInfoCompleteForCloseFile(
   // 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(