Improve input handling for WaveAudioHandler.

media/audio/simple_sources.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.
 
 #ifndef MEDIA_AUDIO_SIMPLE_SOURCES_H_
 #define MEDIA_AUDIO_SIMPLE_SOURCES_H_
 
 #include "base/files/file_path.h"
 #include "base/synchronization/lock.h"
 #include "media/audio/audio_io.h"
@@ skipping 30 matching lines @@
  protected:
   int channels_;
   double f_;
   int time_state_;
   int cap_;
   int callbacks_;
   int errors_;
   base::Lock time_lock_;
 };
 
-class FileSource : public AudioOutputStream::AudioSourceCallback,
-                   public AudioConverter::InputCallback {
+class MEDIA_EXPORT FileSource : public AudioOutputStream::AudioSourceCallback,
+                                public AudioConverter::InputCallback {
  public:
   FileSource(const AudioParameters& params,
              const base::FilePath& path_to_wav_file);
   ~FileSource() override;
 
   // Implementation of AudioSourceCallback.
   int OnMoreData(AudioBus* audio_bus, uint32 total_bytes_delay) override;
   void OnError(AudioOutputStream* stream) override;
 
  private:
   AudioParameters params_;
   base::FilePath path_to_wav_file_;
-  scoped_ptr<uint8[]> wav_file_data_;
+
+  // The WAV data at |path_to_wav_file_| is read into memory and kept here.
+  // This memory needs to survive for the lifetime of |wav_audio_handler_|,
+  // so declare it first. Do not access this member directly.
+  scoped_ptr<char[]> raw_wav_data_;
+
   scoped_ptr<WavAudioHandler> wav_audio_handler_;
   scoped_ptr<AudioConverter> file_audio_converter_;
   int wav_file_read_pos_;
   bool load_failed_;
 
   // Provides audio data from wav_audio_handler_ into the file audio converter.
   double ProvideInput(AudioBus* audio_bus,
                       base::TimeDelta buffer_delay) override;
 
   // Loads the wav file on the first OnMoreData invocation.
@@ skipping 17 matching lines @@
   base::TimeTicks last_callback_time_;
   base::TimeDelta interval_from_last_beep_;
   int beep_duration_in_buffers_;
   int beep_generated_in_buffers_;
   int beep_period_in_frames_;
 };
 
 }  // namespace media
 
 #endif  // MEDIA_AUDIO_SIMPLE_SOURCES_H_