Change how <video> fetch a resource to make it friendly to sparse caching

webkit/glue/media/buffered_data_source.h

 // Copyright (c) 2009 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.
 
 #ifndef WEBKIT_GLUE_MEDIA_BUFFERED_DATA_SOURCE_H_
 #define WEBKIT_GLUE_MEDIA_BUFFERED_DATA_SOURCE_H_
 
 #include <string>
 
 #include "base/lock.h"
@@ skipping 33 matching lines @@
       int64 first_byte_position,
       int64 last_byte_position);
   virtual ~BufferedResourceLoader();
 
   // Start the resource loading with the specified URL and range.
   // This method operates in asynchronous mode. Once there's a response from the
   // server, success or fail |callback| is called with the result.
   // |callback| is called with the following values:
   // - net::OK
   //   The request has started successfully.
-  // - net::ERR_REQUEST_RANGE_NOT_SATISFIABLE
-  //   A range request was made to the server but the server doesn't support it.
   // - net::ERR_FAILED
   //   The request has failed because of an error with the network.
   // - net::ERR_INVALID_RESPONSE
   //   An invalid response is received from the server.
   // - (Anything else)
   //   An error code that indicates the request has failed.
   virtual void Start(net::CompletionCallback* callback);
 
   // Stop this loader, cancels and request and release internal buffer.
   virtual void Stop();
@@ skipping 12 matching lines @@
                     uint8* buffer, net::CompletionCallback* callback);
 
   // Gets the content length in bytes of the instance after this loader has been
   // started. If this value is -1, then content length is unknown.
   virtual int64 content_length() { return content_length_; }
 
   // Gets the original size of the file requested. If this value is -1, then
   // the size is unknown.
   virtual int64 instance_size() { return instance_size_; }
 
+  // Returns true if the response for this loader is a partial response.
+  // It means a 206 response in HTTP/HTTPS protocol.
+  virtual bool partial_response() { return partial_response_; }
+
   /////////////////////////////////////////////////////////////////////////////
   // webkit_glue::ResourceLoaderBridge::Peer implementations.
   virtual void OnUploadProgress(uint64 position, uint64 size) {}
   virtual bool OnReceivedRedirect(
       const GURL& new_url,
       const webkit_glue::ResourceLoaderBridge::ResponseInfo& info);
   virtual void OnReceivedResponse(
       const webkit_glue::ResourceLoaderBridge::ResponseInfo& info,
       bool content_filtered);
   virtual void OnReceivedData(const char* data, int len);
@@ skipping 32 matching lines @@
   void DoneRead(int error);
 
   // Done with start. Invokes the start callback and reset it.
   void DoneStart(int error);
 
   bool HasPendingRead() { return read_callback_.get() != NULL; }
 
   // A sliding window of buffer.
   scoped_ptr<media::SeekableBuffer> buffer_;
 
+  // True if resource loading is deffered.

[scherkus (not reviewing), 2009/09/29 23:10:34]

deffered -> deferred

   bool deferred_;
+
+  // True if resource loading is completed.

[scherkus (not reviewing), 2009/09/29 23:10:34]

is -> has

   bool completed_;
+
+  // True if a range request is made.

[scherkus (not reviewing), 2009/09/29 23:10:34]

is -> was

   bool range_requested_;
 
+  // True if response data received is a partial range.

[scherkus (not reviewing), 2009/09/29 23:10:34]

is -> was

+  bool partial_response_;
+
   webkit_glue::MediaResourceLoaderBridgeFactory* bridge_factory_;
   GURL url_;
   int64 first_byte_position_;
   int64 last_byte_position_;
 
   // Members used during request start.
   scoped_ptr<net::CompletionCallback> start_callback_;
   scoped_ptr<webkit_glue::ResourceLoaderBridge> bridge_;
   int64 offset_;
   int64 content_length_;
@@ skipping 96 matching lines @@
   // Calls |read_callback_| and reset all read parameters.
   void DoneRead(int error);
 
   // Calls |initialize_callback_| and reset it.
   void DoneInitialization();
 
   // Callback method for |loader_|. This method is called when response for
   // initial request is received.
   void InitialStartCallback(int error);
 
-  // Callback method for |probe_loader_|. This method is called when the
-  // response for probe request is received.
-  void ProbeStartCallback(int error);
-
   // Callback method to be passed to BufferedResourceLoader during range
   // request. Once a resource request has started, this method will be called
   // with the error code. This method will be executed on the thread
   // BufferedResourceLoader lives, i.e. render thread.
   void PartialReadStartCallback(int error);
 
   // Callback method for making a read request to BufferedResourceLoader.
   // If data arrives or the request has failed, this method is called with
   // the error code or the number of bytes read.
   void ReadCallback(int error);
@@ skipping 12 matching lines @@
   // This value will be true if this data source can only support streaming.
   // i.e. range request is not supported.
   bool streaming_;
 
   // A factory object to produce ResourceLoaderBridge.
   scoped_ptr<webkit_glue::MediaResourceLoaderBridgeFactory> bridge_factory_;
 
   // A resource loader for the media resource.
   scoped_refptr<BufferedResourceLoader> loader_;
 
-  // A resource loader that probes the server's ability to serve range requests.
-  scoped_refptr<BufferedResourceLoader> probe_loader_;
-
   // Callback method from the pipeline for initialization.
   scoped_ptr<media::FilterCallback> initialize_callback_;
 
   // Read parameters received from the Read() method call.
   scoped_ptr<media::DataSource::ReadCallback> read_callback_;
   int64 read_position_;
   int read_size_;
   uint8* read_buffer_;
   base::Time read_submitted_time_;
   int read_attempts_;
 
-  // This flag is set to true if the initial request has started.
-  bool initial_response_received_;
-
-  // This flag is set to true if the probe request has started.
-  bool probe_response_received_;
-
   // This buffer is intermediate, we use it for BufferedResourceLoader to write
   // to. And when read in BufferedResourceLoader is done, we copy data from
   // this buffer to |read_buffer_|. The reason for an additional copy is that
   // we don't own |read_buffer_|. But since the read operation is asynchronous,
   // |read_buffer| can be destroyed at any time, so we only copy into
   // |read_buffer| in the final step when it is safe.
   // Memory is allocated for this member during initialization of this object
   // because we want buffer to be passed into BufferedResourceLoader to be
   // always non-null. And by initializing this member with a default size we can
   // avoid creating zero-sized buffered if the first read has zero size.
@@ skipping 19 matching lines @@
   // loop. The RepeatingTimer does PostDelayedTask() internally, by using it
   // the message loop doesn't hold a reference for the watch dog task.
   base::RepeatingTimer<BufferedDataSource> watch_dog_timer_;
 
   DISALLOW_COPY_AND_ASSIGN(BufferedDataSource);
 };
 
 }  // namespace webkit_glue
 
 #endif  // WEBKIT_GLUE_MEDIA_BUFFERED_DATA_SOURCE_H_