Separate BufferedDataSource and BufferedResourceLoader into two files.

webkit/glue/media/buffered_resource_loader.h

+// Copyright (c) 2010 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_RESOURCE_LOADER_H_
+#define WEBKIT_GLUE_MEDIA_BUFFERED_RESOURCE_LOADER_H_
+
+#include <string>
+
+#include "base/callback.h"
+#include "base/lock.h"
+#include "base/scoped_ptr.h"
+#include "base/timer.h"
+#include "googleurl/src/gurl.h"
+#include "media/base/seekable_buffer.h"
+#include "net/base/file_stream.h"
+#include "third_party/WebKit/WebKit/chromium/public/WebFrame.h"
+#include "third_party/WebKit/WebKit/chromium/public/WebURLLoader.h"
+#include "third_party/WebKit/WebKit/chromium/public/WebURLLoaderClient.h"
+#include "third_party/WebKit/WebKit/chromium/public/WebURLRequest.h"
+#include "webkit/glue/media/web_data_source.h"
+#include "webkit/glue/webmediaplayer_impl.h"
+
+namespace webkit_glue {
+
+// This class works inside demuxer thread and render thread. It contains a
+// WebURLLoader and does the actual resource loading. This object does
+// buffering internally, it defers the resource loading if buffer is full
+// and un-defers the resource loading if it is under buffered.
+class BufferedResourceLoader :
+    public base::RefCountedThreadSafe<BufferedResourceLoader>,
+    public WebKit::WebURLLoaderClient {
+ public:
+  typedef Callback0::Type NetworkEventCallback;
+
+  // |url| - URL for the resource to be loaded.
+  // |first_byte_position| - First byte to start loading from, -1 for not
+  // specified.
+  // |last_byte_position| - Last byte to be loaded, -1 for not specified.
+  BufferedResourceLoader(const GURL& url,
+                         int64 first_byte_position,
+                         int64 last_byte_position);
+
+  // 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_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.
+  // |event_callback| is called when the response is completed, data is
+  // received, the request is suspended or resumed.
+  virtual void Start(net::CompletionCallback* callback,
+                     NetworkEventCallback* event_callback,
+                     WebKit::WebFrame* frame);
+
+  // Stop this loader, cancels and request and release internal buffer.
+  virtual void Stop();
+
+  // Reads the specified |read_size| from |position| into |buffer| and when
+  // the operation is done invoke |callback| with number of bytes read or an
+  // error code.
+  // |callback| is called with the following values:
+  // - (Anything greater than or equal 0)
+  //   Read was successful with the indicated number of bytes read.
+  // - net::ERR_FAILED
+  //   The read has failed because of an error with the network.
+  // - net::ERR_CACHE_MISS
+  //   The read was made too far away from the current buffered position.
+  virtual void Read(int64 position, int read_size,
+                    uint8* buffer, net::CompletionCallback* callback);
+
+  // Returns the position of the first byte buffered. Returns -1 if such value
+  // is not available.
+  virtual int64 GetBufferedFirstBytePosition();
+
+  // Returns the position of the last byte buffered. Returns -1 if such value
+  // is not available.
+  virtual int64 GetBufferedLastBytePosition();
+
+  // Sets whether deferring data is allowed or disallowed.
+  virtual void SetAllowDefer(bool is_allowed);
+
+  // 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_; }
+
+  // Returns true if network is currently active.
+  virtual bool network_activity() { return !completed_ && !deferred_; }
+
+  // Returns resulting URL.
+  virtual const GURL& url() { return url_; }
+
+  // Used to inject a mock used for unittests.
+  virtual void SetURLLoaderForTest(WebKit::WebURLLoader* mock_loader);
+
+  /////////////////////////////////////////////////////////////////////////////
+  // WebKit::WebURLLoaderClient implementations.
+  virtual void willSendRequest(
+      WebKit::WebURLLoader* loader,
+      WebKit::WebURLRequest& newRequest,
+      const WebKit::WebURLResponse& redirectResponse);
+  virtual void didSendData(
+      WebKit::WebURLLoader* loader,
+      unsigned long long bytesSent,
+      unsigned long long totalBytesToBeSent);
+  virtual void didReceiveResponse(
+      WebKit::WebURLLoader* loader,
+      const WebKit::WebURLResponse& response);
+  virtual void didDownloadData(
+      WebKit::WebURLLoader* loader,
+      int dataLength);
+  virtual void didReceiveData(
+      WebKit::WebURLLoader* loader,
+      const char* data,
+      int dataLength);
+  virtual void didReceiveCachedMetadata(
+      WebKit::WebURLLoader* loader,
+      const char* data, int dataLength);
+  virtual void didFinishLoading(
+      WebKit::WebURLLoader* loader,
+      double finishTime);
+  virtual void didFail(
+      WebKit::WebURLLoader* loader,
+      const WebKit::WebURLError&);
+
+ protected:
+  friend class base::RefCountedThreadSafe<BufferedResourceLoader>;
+
+  virtual ~BufferedResourceLoader();
+
+ private:
+  friend class BufferedResourceLoaderTest;
+
+  // Defer the resource loading if the buffer is full.
+  void EnableDeferIfNeeded();
+
+  // Disable defer loading if we are under-buffered.
+  void DisableDeferIfNeeded();
+
+  // Returns true if the current read request can be fulfilled by what is in
+  // the buffer.
+  bool CanFulfillRead();
+
+  // Returns true if the current read request will be fulfilled in the future.
+  bool WillFulfillRead();
+
+  // Method that does the actual read and calls the |read_callbac_|, assuming
+  // the request range is in |buffer_|.
+  void ReadInternal();
+
+  // If we have made a range request, verify the response from the server.
+  bool VerifyPartialResponse(const WebKit::WebURLResponse& response);
+
+  // Returns the value for a range request header using parameters
+  // |first_byte_position| and |last_byte_position|. Negative numbers other
+  // than -1 are not allowed for |first_byte_position| and |last_byte_position|.
+  // |first_byte_position| should always be less than or equal to
+  // |last_byte_position| if they are both not -1.
+  // Empty string is returned on invalid parameters.
+  std::string GenerateHeaders(int64 first_byte_position,
+                              int64 last_byte_position);
+
+  // Done with read. Invokes the read callback and reset parameters for the
+  // read request.
+  void DoneRead(int error);
+
+  // Done with start. Invokes the start callback and reset it.
+  void DoneStart(int error);
+
+  // Calls |event_callback_| in terms of a network event.
+  void NotifyNetworkEvent();
+
+  bool HasPendingRead() { return read_callback_.get() != NULL; }
+
+  // A sliding window of buffer.
+  scoped_ptr<media::SeekableBuffer> buffer_;
+
+  // True if resource loading was deferred.
+  bool deferred_;
+
+  // True if resource loader is allowed to defer, false otherwise.
+  bool defer_allowed_;
+
+  // True if resource loading has completed.
+  bool completed_;
+
+  // True if a range request was made.
+  bool range_requested_;
+
+  // True if response data received is a partial range.
+  bool partial_response_;
+
+  // Does the work of loading and sends data back to this client.
+  scoped_ptr<WebKit::WebURLLoader> url_loader_;
+
+  GURL url_;
+  int64 first_byte_position_;
+  int64 last_byte_position_;
+
+  // Callback method that listens to network events.
+  scoped_ptr<NetworkEventCallback> event_callback_;
+
+  // Members used during request start.
+  scoped_ptr<net::CompletionCallback> start_callback_;
+  int64 offset_;
+  int64 content_length_;
+  int64 instance_size_;
+
+  // Members used during a read operation. They should be reset after each
+  // read has completed or failed.
+  scoped_ptr<net::CompletionCallback> read_callback_;
+  int64 read_position_;
+  int read_size_;
+  uint8* read_buffer_;
+
+  // Offsets of the requested first byte and last byte in |buffer_|. They are
+  // written by VerifyRead().
+  int first_offset_;
+  int last_offset_;
+
+  // Used to ensure mocks for unittests are used instead of reset in Start().
+  bool keep_test_loader_;
+
+  DISALLOW_COPY_AND_ASSIGN(BufferedResourceLoader);
+};
+
+}  // namespace webkit_glue
+
+#endif  // WEBKIT_GLUE_MEDIA_BUFFERED_RESOURCE_LOADER_H_