Introducing DecoderBuffer and general Buffer cleanup.

media/base/decoder_buffer.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.
+
+// A specialized buffer for interfacing with audio / video decoders.
+//
+// Specifically ensures that data is aligned and padded as necessary by the
+// underlying decoding framework.  On desktop platforms this means memory is
+// allocated using FFmpeg with particular alignment and padding requirements.
+//
+// Also includes decoder specific functionality for decryption.
+
+#ifndef MEDIA_BASE_DECODER_BUFFER_H_
+#define MEDIA_BASE_DECODER_BUFFER_H_
+
+#include "base/memory/scoped_ptr.h"
+#include "media/base/buffers.h"
+#include "media/base/decrypt_config.h"
+#if !defined(OS_ANDROID)
+#include "media/ffmpeg/ffmpeg_common.h"

[scherkus (not reviewing), 2012/05/26 01:36:32]

this header file should only be included by .cc files as it pulls in the FFmpeg
header files and pollutes the namespace

It looks like the only reason it's included is for ScopedPtrAVFree but I'd
prefer to use av_malloc/av_free inside this class (with #if guards for android)
instead of having ffmpeg_common.h included here (we're not doing anything tricky
involve complicated scopes inside this class so we're not losing out on much by
not using it)

[DaleCurtis, 2012/05/29 21:17:01]

Done.

+#endif
+
+namespace media {
+
+class MEDIA_EXPORT DecoderBuffer : public Buffer {
+ public:
+  // Allocates buffer of size |buffer_size|.  If |buffer_size| is 0, |data_| is
+  // set to a NULL ptr.  Buffer will be padded and aligned as needed for decode.
+  explicit DecoderBuffer(int buffer_size);
+
+  // Create a DataBuffer whose |data_| is copied from |data|.  Buffer will be
+  // padded and aligned as needed for decode.
+  static scoped_refptr<DecoderBuffer> CopyFrom(const uint8* data, int size);
+
+  // Buffer implementation.
+  virtual const uint8* GetData() const OVERRIDE;
+  virtual int GetDataSize() const OVERRIDE;
+
+  // Returns a read-write pointer to the buffer data.
+  virtual uint8* GetWritableData();
+
+  virtual const DecryptConfig* GetDecryptConfig() const;
+  virtual void SetDecryptConfig(scoped_ptr<DecryptConfig> decrypt_config);
+
+ protected:
+  DecoderBuffer(const uint8* data, int size);
+  virtual ~DecoderBuffer();
+
+ private:
+  int buffer_size_;
+#if !defined(OS_ANDROID)
+  scoped_ptr_malloc<uint8, ScopedPtrAVFree> data_;
+#else
+  scoped_array<uint8> data_;
+#endif
+  scoped_ptr<DecryptConfig> decrypt_config_;
+
+  // Constructor helper method for memory allocations.
+  void Initialize();
+
+  DISALLOW_COPY_AND_ASSIGN(DecoderBuffer);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_BASE_DECODER_BUFFER_H_