Add the base class for decoder buffers used in cast media.

Creates a decoder buffer base class that exposes only the properties
of a decoder buffer. This makes it possible to hide how a buffer
is created and how it is organized in memory, this is left
as an implementation detail of derived classes.

BUG=408189

Review URL: https://codereview.chromium.org/535563002

Cr-Commit-Position: refs/heads/master@{#293298}

chromecast/media/cma/base/decoder_buffer_adapter.cc

+// Copyright 2014 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.
+
+#include "chromecast/media/cma/base/decoder_buffer_adapter.h"
+
+#include "media/base/decoder_buffer.h"
+
+namespace chromecast {
+namespace media {
+
+DecoderBufferAdapter::DecoderBufferAdapter(
+    const scoped_refptr< ::media::DecoderBuffer>& buffer)
+    : buffer_(buffer) {
+}
+
+DecoderBufferAdapter::~DecoderBufferAdapter() {
+}
+
+base::TimeDelta DecoderBufferAdapter::timestamp() const {
+  return buffer_->timestamp();
+}
+
+const uint8* DecoderBufferAdapter::data() const {
+  return buffer_->data();
+}
+
+uint8* DecoderBufferAdapter::writable_data() const {
+  return buffer_->writable_data();
+}
+
+int DecoderBufferAdapter::data_size() const {
+  return buffer_->data_size();
+}
+
+const ::media::DecryptConfig* DecoderBufferAdapter::decrypt_config() const {
+  return buffer_->decrypt_config();
+}
+
+bool DecoderBufferAdapter::end_of_stream() const {
+  return buffer_->end_of_stream();
+}
+
+}  // namespace media
+}  // namespace chromecast

chromecast/media/cma/base/decoder_buffer_adapter.h

+// Copyright 2014 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 CHROMECAST_MEDIA_CMA_BASE_DECODER_BUFFER_ADAPTER_H_
+#define CHROMECAST_MEDIA_CMA_BASE_DECODER_BUFFER_ADAPTER_H_
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "chromecast/media/cma/base/decoder_buffer_base.h"
+
+namespace media {
+class DecoderBuffer;
+}
+
+namespace chromecast {
+namespace media {
+
+// DecoderBufferAdapter wraps a ::media::DecoderBuffer
+// into a DecoderBufferBase.
+class DecoderBufferAdapter : public DecoderBufferBase {
+ public:
+  explicit DecoderBufferAdapter(
+      const scoped_refptr< ::media::DecoderBuffer>& buffer);
+
+  // DecoderBufferBase implementation.
+  virtual base::TimeDelta timestamp() const OVERRIDE;
+  virtual const uint8* data() const OVERRIDE;
+  virtual uint8* writable_data() const OVERRIDE;
+  virtual int data_size() const OVERRIDE;
+  virtual const ::media::DecryptConfig* decrypt_config() const OVERRIDE;
+  virtual bool end_of_stream() const OVERRIDE;
+
+ private:
+  virtual ~DecoderBufferAdapter();
+
+  scoped_refptr< ::media::DecoderBuffer> const buffer_;
+
+  DISALLOW_COPY_AND_ASSIGN(DecoderBufferAdapter);
+};
+
+}  // namespace media
+}  // namespace chromecast
+
+#endif  // CHROMECAST_MEDIA_CMA_BASE_DECODER_BUFFER_ADAPTER_H_

chromecast/media/cma/base/decoder_buffer_base.cc

+// Copyright 2014 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.
+
+#include "chromecast/media/cma/base/decoder_buffer_base.h"
+
+namespace chromecast {
+namespace media {
+
+DecoderBufferBase::DecoderBufferBase() {
+}
+
+DecoderBufferBase::~DecoderBufferBase() {
+}
+
+}  // namespace media
+}  // namespace chromecast

chromecast/media/cma/base/decoder_buffer_base.h

+// Copyright 2014 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 CHROMECAST_MEDIA_CMA_BASE_DECODER_BUFFER_BASE_H_
+#define CHROMECAST_MEDIA_CMA_BASE_DECODER_BUFFER_BASE_H_
+
+#include "base/basictypes.h"
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/time/time.h"
+
+namespace media {
+class DecryptConfig;
+}
+
+namespace chromecast {
+namespace media {
+
+// DecoderBufferBase exposes only the properties of an audio/video buffer.
+// The way a DecoderBufferBase is created and organized in memory
+// is left as a detail of the implementation of derived classes.
+class DecoderBufferBase
+    : public base::RefCountedThreadSafe<DecoderBufferBase> {
+ public:
+  DecoderBufferBase();
+
+  // Returns the PTS of the frame.
+  virtual base::TimeDelta timestamp() const = 0;
+
+  // Gets the frame data.
+  virtual const uint8* data() const = 0;
+  virtual uint8* writable_data() const = 0;
+
+  // Returns the size of the frame in bytes.
+  virtual int data_size() const = 0;
+
+  // Returns the decrypt configuration.
+  // Returns NULL if the buffer has no decrypt info.
+  virtual const ::media::DecryptConfig* decrypt_config() const = 0;
+
+  // Indicate if this is a special frame that indicates the end of the stream.
+  // If true, functions to access the frame content cannot be called.
+  virtual bool end_of_stream() const = 0;
+
+ protected:
+  friend class base::RefCountedThreadSafe<DecoderBufferBase>;
+  virtual ~DecoderBufferBase();
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(DecoderBufferBase);
+};
+
+}  // namespace media
+}  // namespace chromecast
+
+#endif  // CHROMECAST_MEDIA_CMA_BASE_DECODER_BUFFER_BASE_H_

chromecast/media/media.gyp

@@ -20,6 +20,10 @@
         'cma/base/buffering_state.cc',
         'cma/base/buffering_state.h',
         'cma/base/cma_logging.h',
+        'cma/base/decoder_buffer_adapter.cc',
+        'cma/base/decoder_buffer_adapter.h',
+        'cma/base/decoder_buffer_base.cc',
+        'cma/base/decoder_buffer_base.h',
       ],
     },
     {