Chromium Code Reviews
chromiumcodereview-hr@appspot.gserviceaccount.com (chromiumcodereview-hr) | Please choose your nickname with Settings | Help | Chromium Project | Gerrit Changes | Sign out
(667)

Unified Diff: chrome/browser/dom_ui/chrome_url_data_manager.h

Issue 6479007: Attempt 3 at: Splits ChromeURLDataManager into 2 chunks:... (Closed) Base URL: svn://chrome-svn/chrome/trunk/src/
Patch Set: '' Created 9 years, 10 months ago
Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.
Jump to:
View side-by-side diff with in-line comments
Download patch
Index: chrome/browser/dom_ui/chrome_url_data_manager.h
===================================================================
--- chrome/browser/dom_ui/chrome_url_data_manager.h (revision 74394)
+++ chrome/browser/dom_ui/chrome_url_data_manager.h (working copy)
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
@@ -9,35 +9,45 @@
#include <map>
#include <string>
-#include "base/singleton.h"
#include "base/task.h"
#include "base/ref_counted.h"
#include "chrome/browser/browser_thread.h"
+class ChromeURLDataManagerBackend;
class DictionaryValue;
class FilePath;
-class GURL;
class MessageLoop;
+class Profile;
class RefCountedMemory;
-class URLRequestChromeJob;
-namespace net {
-class URLRequest;
-class URLRequestJob;
-} // namespace net
-
// To serve dynamic data off of chrome: URLs, implement the
// ChromeURLDataManager::DataSource interface and register your handler
-// with AddDataSource.
-
-// ChromeURLDataManager lives on the IO thread, so any interfacing with
-// it from the UI thread needs to go through an InvokeLater.
+// with AddDataSource. DataSources must be added on the UI thread (they are also
+// deleted on the UI thread). Internally the DataSources are maintained by
+// ChromeURLDataManagerBackend, see it for details.
class ChromeURLDataManager {
public:
- // Returns the singleton instance.
- static ChromeURLDataManager* GetInstance();
+ class DataSource;
- typedef int RequestID;
+ // Trait used to handle deleting a DataSource. Deletion happens on the UI
+ // thread.
+ //
+ // Implementation note: the normal shutdown sequence is for the UI loop to
+ // stop pumping events then the IO loop and thread are stopped. When the
+ // DataSources are no longer referenced (which happens when IO thread stops)
+ // they get added to the UI message loop for deletion. But because the UI loop
+ // has stopped by the time this happens the DataSources would be leaked.
+ //
+ // To make sure DataSources are properly deleted ChromeURLDataManager manages
+ // deletion of the DataSources. When a DataSource is no longer referenced it
+ // is added to |data_sources_| and a task is posted to the UI thread to handle
+ // the actual deletion. During shutdown |DeleteDataSources| is invoked so that
+ // all pending DataSources are properly deleted.
+ struct DeleteDataSource {
+ static void Destruct(const DataSource* data_source) {
+ ChromeURLDataManager::DeleteDataSource(data_source);
+ }
+ };
// A DataSource is an object that can answer requests for data
// asynchronously. DataSources are collectively owned with refcounting smart
@@ -49,11 +59,10 @@
// StartDataRequest() by starting its (implementation-specific) asynchronous
// request for the data, then call SendResponse() to notify.
class DataSource : public base::RefCountedThreadSafe<
- DataSource, BrowserThread::DeleteOnUIThread> {
+ DataSource, DeleteDataSource> {
public:
// See source_name_ and message_loop_ below for docs on these parameters.
- DataSource(const std::string& source_name,
- MessageLoop* message_loop);
+ DataSource(const std::string& source_name, MessageLoop* message_loop);
// Sent by the DataManager to request data at |path|. The source should
// call SendResponse() when the data is available or if the request could
@@ -88,13 +97,18 @@
static void SetFontAndTextDirection(DictionaryValue* localized_strings);
protected:
- friend class base::RefCountedThreadSafe<DataSource>;
- friend struct BrowserThread::DeleteOnThread<BrowserThread::UI>;
- friend class DeleteTask<DataSource>;
-
virtual ~DataSource();
private:
+ friend class ChromeURLDataManagerBackend;
+ friend class ChromeURLDataManager;
+ friend class DeleteTask<DataSource>;
+
+ // SendResponse invokes this on the IO thread. Notifies the backend to
+ // handle the actual work of sending the data.
+ virtual void SendResponseOnIOThread(int request_id,
+ scoped_refptr<RefCountedMemory> bytes);
+
// The name of this source.
// E.g., for favicons, this could be "favicon", which results in paths for
// specific resources like "favicon/34" getting sent to this source.
@@ -103,89 +117,57 @@
// The MessageLoop for the thread where this DataSource lives.
// Used to send messages to the DataSource.
MessageLoop* message_loop_;
+
+ // This field is set and maintained by ChromeURLDataManagerBackend. It is
+ // set when the DataSource is added, and unset if the DataSource is removed.
+ // A DataSource can be removed in two ways: the ChromeURLDataManagerBackend
+ // is deleted, or another DataSource is registered with the same
+ // name. backend_ should only be accessed on the IO thread.
+ // This reference can't be via a scoped_refptr else there would be a cycle
+ // between the backend and data source.
+ ChromeURLDataManagerBackend* backend_;
};
- // Add a DataSource to the collection of data sources.
- // Because we don't track users of a given path, we can't know when it's
- // safe to remove them, so the added source effectively leaks.
- // This could be improved in the future but currently the users of this
- // interface are conceptually permanent registration anyway.
- // Adding a second DataSource with the same name clobbers the first.
- // NOTE: Calling this from threads other the IO thread must be done via
- // InvokeLater.
- void AddDataSource(scoped_refptr<DataSource> source);
- // Called during shutdown, before destruction of |BrowserThread|.
- void RemoveDataSourceForTest(const char* source_name); // For unit tests.
- void RemoveAllDataSources(); // For the browser.
+ explicit ChromeURLDataManager(Profile* profile);
+ ~ChromeURLDataManager();
- // Add/remove a path from the collection of file sources.
- // A file source acts like a file:// URL to the specified path.
- // Calling this from threads other the IO thread must be done via
- // InvokeLater.
- void AddFileSource(const std::string& source_name, const FilePath& path);
- void RemoveFileSource(const std::string& source_name);
+ // Adds a DataSource to the collection of data sources. This *must* be invoked
+ // on the UI thread.
+ //
+ // If |AddDataSource| is called more than once for a particular name it will
+ // release the old |DataSource|, most likely resulting in it getting deleted
+ // as there are no other references to it. |DataSource| uses the
+ // |DeleteOnUIThread| trait to insure that the destructor is called on the UI
+ // thread. This is necessary as some |DataSource|s notably |FileIconSource|
+ // and |WebUIFavIconSource|, have members that will DCHECK if they are not
+ // destructed in the same thread as they are constructed (the UI thread).
+ void AddDataSource(DataSource* source);
- static net::URLRequestJob* Factory(net::URLRequest* request,
- const std::string& scheme);
+ // Deletes any data sources no longer referenced. This is normally invoked
+ // for you, but can be invoked to force deletion (such as during shutdown).
+ static void DeleteDataSources();
private:
- friend class URLRequestChromeJob;
- friend struct DefaultSingletonTraits<ChromeURLDataManager>;
+ typedef std::vector<const ChromeURLDataManager::DataSource*> DataSources;
- ChromeURLDataManager();
- ~ChromeURLDataManager();
+ // If invoked on the UI thread the DataSource is deleted immediatlye,
+ // otherwise it is added to |data_sources_| and a task is scheduled to handle
+ // deletion on the UI thread. See note abouve DeleteDataSource for more info.
+ static void DeleteDataSource(const DataSource* data_source);
- // Parse a URL into the components used to resolve its request.
- static void URLToRequest(const GURL& url,
- std::string* source,
- std::string* path);
+ // Returns true if |data_source| is scheduled for deletion (|DeleteDataSource|
+ // was invoked).
+ static bool IsScheduledForDeletion(const DataSource* data_source);
- // Translate a chrome resource URL into a local file path if there is one.
- // Returns false if there is no file handler for this URL
- static bool URLToFilePath(const GURL& url, FilePath* file_path);
+ Profile* profile_;
- // Called by the job when it's starting up.
- // Returns false if |url| is not a URL managed by this object.
- bool StartRequest(const GURL& url, URLRequestChromeJob* job);
- // Remove a request from the list of pending requests.
- void RemoveRequest(URLRequestChromeJob* job);
+ // Lock used when accessing |data_sources_|.
+ static base::Lock delete_lock_;
- // Returns true if the job exists in |pending_requests_|. False otherwise.
- // Called by ~URLRequestChromeJob to verify that |pending_requests_| is kept
- // up to date.
- bool HasPendingJob(URLRequestChromeJob* job) const;
+ // |data_sources_| that are no longer referenced and scheduled for deletion.
+ static DataSources* data_sources_;
- // Sent by Request::SendResponse.
- void DataAvailable(RequestID request_id,
- scoped_refptr<RefCountedMemory> bytes);
-
- // File sources of data, keyed by source name (e.g. "inspector").
- typedef std::map<std::string, FilePath> FileSourceMap;
- FileSourceMap file_sources_;
-
- // Custom sources of data, keyed by source path (e.g. "favicon").
- typedef std::map<std::string, scoped_refptr<DataSource> > DataSourceMap;
- DataSourceMap data_sources_;
-
- // All pending URLRequestChromeJobs, keyed by ID of the request.
- // URLRequestChromeJob calls into this object when it's constructed and
- // destructed to ensure that the pointers in this map remain valid.
- typedef std::map<RequestID, URLRequestChromeJob*> PendingRequestMap;
- PendingRequestMap pending_requests_;
-
- // The ID we'll use for the next request we receive.
- RequestID next_request_id_;
+ DISALLOW_COPY_AND_ASSIGN(ChromeURLDataManager);
};
-// Since we have a single global ChromeURLDataManager, we don't need to
-// grab a reference to it when creating Tasks involving it.
-DISABLE_RUNNABLE_METHOD_REFCOUNT(ChromeURLDataManager);
-
-// Register our special URL handler under our special URL scheme.
-// Must be done once at startup.
-void RegisterURLRequestChromeJob();
-
-// Undoes the registration done by RegisterURLRequestChromeJob.
-void UnregisterURLRequestChromeJob();
-
#endif // CHROME_BROWSER_DOM_UI_CHROME_URL_DATA_MANAGER_H_

Powered by Google App Engine
This is Rietveld 408576698