Implement simple garbage collection in SourceBufferStream

media/filters/source_buffer_stream.h

 // Copyright (c) 2012 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.
 
 // SourceBufferStream is a data structure that stores media Buffers in ranges.
 // Buffers can be appended out of presentation order. Buffers are retrieved by
 // seeking to the desired start point and calling GetNextBuffer(). Buffers are
 // returned in sequential presentation order.
 
 #ifndef MEDIA_FILTERS_SOURCE_BUFFER_STREAM_H_
@@ skipping 85 matching lines @@
   // Notifies this object that the video config has changed and buffers in
   // future Append() calls should be associated with this new config.
   bool UpdateVideoConfig(const VideoDecoderConfig& config);
 
   // Returns the largest distance between two adjacent buffers in this stream,
   // or an estimate if no two adjacent buffers have been appended to the stream
   // yet.
   base::TimeDelta GetMaxInterbufferDistance() const;
 
  private:
+  friend class SourceBufferStreamTest;
   typedef std::list<SourceBufferRange*> RangeList;
 
+  void set_memory_limit(int memory_limit) { memory_limit_ = memory_limit; }
+
+  // Frees up space if the SourceBufferStream is taking up too much memory.
+  void GarbageCollectIfNeeded();
+
   // Appends |new_buffers| into |range_for_new_buffers_itr|, handling start and
   // end overlaps if necessary.
   // |deleted_next_buffer| is an output parameter that is true if the next
   // buffer that would have been returned from GetNextBuffer() was deleted
   // during this call.
   // |deleted_buffers| is an output parameter containing candidates for
   // |track_buffer_|.
   void InsertIntoExistingRange(
       const RangeList::iterator& range_for_new_buffers_itr,
       const BufferQueue& new_buffers,
@@ skipping 127 matching lines @@
   // True when the next call to Append() begins a new media segment.
   bool new_media_segment_;
 
   // The timestamp of the last buffer appended to the media segment, set to
   // kNoTimestamp() if the beginning of the segment.
   base::TimeDelta last_buffer_timestamp_;
 
   // Stores the largest distance between two adjacent buffers in this stream.
   base::TimeDelta max_interbuffer_distance_;
 
+// The maximum amount of data in bytes the stream will keep in memory.
+  int memory_limit_;
+
   DISALLOW_COPY_AND_ASSIGN(SourceBufferStream);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_SOURCE_BUFFER_STREAM_H_