Revert 66125 -- Broke Windows build - Move FilterType into MediaFilterCollect...

media/base/filters.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.
 
 // Filters are connected in a strongly typed manner, with downstream filters
 // always reading data from upstream filters.  Upstream filters have no clue
 // who is actually reading from them, and return the results via callbacks.
 //
 //                         DemuxerStream(Video) <- VideoDecoder <- VideoRenderer
 // DataSource <- Demuxer <
@@ skipping 25 matching lines @@
 class MessageLoop;
 
 namespace media {
 
 class Buffer;
 class Decoder;
 class DemuxerStream;
 class FilterHost;
 class MediaFilter;
 
+// Identifies the type of filter implementation. Each filter has to be one of
+// the following types. This is used to identify filter object during
+// initialization of pipeline.
+enum FilterType {
+  FILTER_DATA_SOURCE,
+  FILTER_DEMUXER,
+  FILTER_AUDIO_DECODER,
+  FILTER_VIDEO_DECODER,
+  FILTER_AUDIO_RENDERER,
+  FILTER_VIDEO_RENDERER
+};
+
 // Used for completing asynchronous methods.
 typedef Callback0::Type FilterCallback;
 
 class MediaFilter : public base::RefCountedThreadSafe<MediaFilter> {
  public:
   MediaFilter();
 
+  // Return the type of this filter. All implementor has to provide this
+  // method.
+  virtual FilterType filter_type() const = 0;
+
   // Return the major mime type for this filter.
   virtual const char* major_mime_type() const;
 
   // Sets the private member |host_|. This is the first method called by
   // the FilterHost after a filter is created.  The host holds a strong
   // reference to the filter.  The reference held by the host is guaranteed
   // to be released before the host object is destroyed by the pipeline.
   virtual void set_host(FilterHost* host);
 
   virtual FilterHost* host();
@@ skipping 60 matching lines @@
   DISALLOW_COPY_AND_ASSIGN(MediaFilter);
 };
 
 class DataSource : public MediaFilter {
  public:
   typedef Callback1<size_t>::Type ReadCallback;
   static const size_t kReadError = static_cast<size_t>(-1);
 
   virtual bool IsUrlSupported(const std::string& url);
 
+  static FilterType static_filter_type() { return FILTER_DATA_SOURCE; }
+  virtual FilterType filter_type() const;
+
   // Initialize a DataSource for the given URL, executing the callback upon
   // completion.
   virtual void Initialize(const std::string& url, FilterCallback* callback) = 0;
 
   // Reads |size| bytes from |position| into |data|. And when the read is done
   // or failed, |read_callback| is called with the number of bytes read or
   // kReadError in case of error.
   // TODO(hclam): should change |size| to int! It makes the code so messy
   // with size_t and int all over the place..
   virtual void Read(int64 position, size_t size,
                     uint8* data, ReadCallback* read_callback) = 0;
 
   // Returns true and the file size, false if the file size could not be
   // retrieved.
   virtual bool GetSize(int64* size_out) = 0;
 
   // Returns true if we are performing streaming. In this case seeking is
   // not possible.
   virtual bool IsStreaming() = 0;
 };
 
 
 class Demuxer : public MediaFilter {
  public:
+  static FilterType static_filter_type() { return FILTER_DEMUXER; }
+  virtual FilterType filter_type() const;
+
   virtual bool requires_message_loop() const;
   virtual const char* message_loop_name() const;
 
   // Initialize a Demuxer with the given DataSource, executing the callback upon
   // completion.
   virtual void Initialize(DataSource* data_source,
                           FilterCallback* callback) = 0;
 
   // Returns the number of streams available
   virtual size_t GetNumberOfStreams() = 0;
@@ skipping 36 matching lines @@
   // public template function will assign the interface to a scoped_refptr<>.
   virtual void* QueryInterface(const char* interface_id) { return NULL; }
 
   friend class base::RefCountedThreadSafe<DemuxerStream>;
   virtual ~DemuxerStream();
 };
 
 
 class VideoDecoder : public MediaFilter {
  public:
+  static FilterType static_filter_type() { return FILTER_VIDEO_DECODER; }
+  virtual FilterType filter_type() const;
+
   virtual const char* major_mime_type() const;
   virtual bool requires_message_loop() const;
   virtual const char* message_loop_name() const;
 
 
   // Initialize a VideoDecoder with the given DemuxerStream, executing the
   // callback upon completion.
   virtual void Initialize(DemuxerStream* stream, FilterCallback* callback) = 0;
 
   // |set_fill_buffer_done_callback| install permanent callback from downstream
@@ skipping 25 matching lines @@
   VideoDecoder();
   virtual ~VideoDecoder();
 
  private:
   scoped_ptr<ConsumeVideoFrameCallback> consume_video_frame_callback_;
 };
 
 
 class AudioDecoder : public MediaFilter {
  public:
+  static FilterType static_filter_type() { return FILTER_AUDIO_DECODER; }
+  virtual FilterType filter_type() const;
+
   virtual const char* major_mime_type() const;
   virtual bool requires_message_loop() const;
   virtual const char* message_loop_name() const;
 
   // Initialize a AudioDecoder with the given DemuxerStream, executing the
   // callback upon completion.
   virtual void Initialize(DemuxerStream* stream, FilterCallback* callback) = 0;
 
   // |set_fill_buffer_done_callback| install permanent callback from downstream
   // filter (i.e. Renderer). The callback is used to deliver buffers at
@@ skipping 19 matching lines @@
   AudioDecoder();
   ~AudioDecoder();
 
  private:
   scoped_ptr<ConsumeAudioSamplesCallback> consume_audio_samples_callback_;
 };
 
 
 class VideoRenderer : public MediaFilter {
  public:
+  static FilterType static_filter_type() { return FILTER_VIDEO_RENDERER; }
+  virtual FilterType filter_type() const;
+
   virtual const char* major_mime_type() const;
 
   // Initialize a VideoRenderer with the given VideoDecoder, executing the
   // callback upon completion.
   virtual void Initialize(VideoDecoder* decoder, FilterCallback* callback) = 0;
 
   // Returns true if this filter has received and processed an end-of-stream
   // buffer.
   virtual bool HasEnded() = 0;
 };
 
 
 class AudioRenderer : public MediaFilter {
  public:
+  static FilterType static_filter_type() { return FILTER_AUDIO_RENDERER; }
+  virtual FilterType filter_type() const;
+
   virtual const char* major_mime_type() const;
 
   // Initialize a AudioRenderer with the given AudioDecoder, executing the
   // callback upon completion.
   virtual void Initialize(AudioDecoder* decoder, FilterCallback* callback) = 0;
 
   // Returns true if this filter has received and processed an end-of-stream
   // buffer.
   virtual bool HasEnded() = 0;
 
   // Sets the output volume.
   virtual void SetVolume(float volume) = 0;
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_FILTERS_H_