Refactor WritableBuffer interface for more useful ptr management.

media/filters/ffmpeg_audio_decoder.cc

 // Copyright (c) 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.
 
 #include "media/base/data_buffer.h"
 #include "media/filters/ffmpeg_audio_decoder.h"
 #include "media/filters/ffmpeg_common.h"
 #include "media/filters/ffmpeg_demuxer.h"
 
 namespace media {
@@ skipping 89 matching lines @@
   // of a size_t.
   if (result < 0 ||
       output_buffer_size < 0 ||
       static_cast<size_t>(output_buffer_size) > kOutputBufferSize) {
     host()->Error(PIPELINE_ERROR_DECODE);
     return;
   }
 
   // If we have decoded something, enqueue the result.
   if (output_buffer_size) {
-    DataBuffer* result_buffer = new DataBuffer();
-    memcpy(result_buffer->GetWritableData(output_buffer_size),
-           output_buffer, output_buffer_size);
+    DataBuffer* result_buffer = new DataBuffer(output_buffer_size);
+    uint8* data = result_buffer->GetWritableData();
+    memcpy(data, output_buffer, output_buffer_size);
 
     // Determine the duration if the demuxer couldn't figure it out, otherwise
     // copy it over.
     if (input->GetDuration().InMicroseconds() == 0) {
       result_buffer->SetDuration(CalculateDuration(output_buffer_size));
     } else {
       result_buffer->SetDuration(input->GetDuration());
     }
 
     // Copy over the timestamp.
     result_buffer->SetTimestamp(input->GetTimestamp());
 
     EnqueueResult(result_buffer);
     return;
   }
 
   // Three conditions to meet to declare end of stream for this decoder:
   // 1. FFmpeg didn't read anything.
   // 2. FFmpeg didn't output anything.
   // 3. An end of stream buffer is received.
   if (result == 0 && output_buffer_size == 0 && input->IsEndOfStream()) {
-    DataBuffer* result_buffer = new DataBuffer();
+    DataBuffer* result_buffer = new DataBuffer(0);
     result_buffer->SetTimestamp(input->GetTimestamp());
     result_buffer->SetDuration(input->GetDuration());
     EnqueueResult(result_buffer);
   }
 }
 
 base::TimeDelta FFmpegAudioDecoder::CalculateDuration(size_t size) {
   int64 denominator = codec_context_->channels *
       av_get_bits_per_sample_format(codec_context_->sample_fmt) / 8 *
       codec_context_->sample_rate;
   double microseconds = size /
       (denominator / static_cast<double>(base::Time::kMicrosecondsPerSecond));
   return base::TimeDelta::FromMicroseconds(static_cast<int64>(microseconds));
 }
 
 }  // namespace