Pipeline will execute a callback whenever an run-time error has happened....

media/base/pipeline_impl.h

 // Copyright (c) 2008-2009 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.
 
 // Implementation of Pipeline.
 
 #ifndef MEDIA_BASE_PIPELINE_IMPL_H_
 #define MEDIA_BASE_PIPELINE_IMPL_H_
 
+#include <map>
+#include <set>
 #include <string>
 #include <vector>
-#include <set>
 
 #include "base/message_loop.h"
 #include "base/ref_counted.h"
 #include "base/thread.h"
 #include "base/time.h"
 #include "media/base/filter_host.h"
 #include "media/base/pipeline.h"
 
 namespace media {
 
@@ skipping 52 matching lines @@
   virtual float GetVolume() const;
   virtual void SetVolume(float volume);
   virtual base::TimeDelta GetCurrentTime() const;
   virtual base::TimeDelta GetBufferedTime() const;
   virtual base::TimeDelta GetDuration() const;
   virtual int64 GetBufferedBytes() const;
   virtual int64 GetTotalBytes() const;
   virtual void GetVideoSize(size_t* width_out, size_t* height_out) const;
   virtual PipelineError GetError() const;
 
+  // |error_callback_| will be executed upon an error in the pipeline. If
+  // |error_callback_| is NULL, it is ignored. The pipeline takes ownernship
+  // of |error_callback|.
+  virtual void SetPipelineErrorCallback(PipelineCallback* error_callback);
+
  private:
   // Pipeline states, as described above.
   enum State {
     kCreated,
     kInitDataSource,
     kInitDemuxer,
     kInitAudioDecoder,
     kInitAudioRenderer,
     kInitVideoDecoder,
     kInitVideoRenderer,
@@ skipping 212 matching lines @@
 
   // Filter factory as passed in by Start().
   scoped_refptr<FilterFactory> filter_factory_;
 
   // URL for the data source as passed in by Start().
   std::string url_;
 
   // Callbacks for various pipeline operations.
   scoped_ptr<PipelineCallback> seek_callback_;
   scoped_ptr<PipelineCallback> stop_callback_;
+  scoped_ptr<PipelineCallback> error_callback_;
 
   // Vector of our filters and map maintaining the relationship between the
   // FilterType and the filter itself.
   typedef std::vector<scoped_refptr<MediaFilter> > FilterVector;
   FilterVector filters_;
 
   typedef std::map<FilterType, scoped_refptr<MediaFilter> > FilterTypeMap;
   FilterTypeMap filter_types_;
 
   // Vector of threads owned by the pipeline and being used by filters.
   typedef std::vector<base::Thread*> FilterThreadVector;
   FilterThreadVector filter_threads_;
 
   DISALLOW_COPY_AND_ASSIGN(PipelineImpl);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_PIPELINE_IMPL_H_