Audio output debug recording.

media/audio/audio_debug_recording_manager.h

+// Copyright 2017 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_AUDIO_DEBUG_RECORDING_MANAGER_H_
+#define MEDIA_AUDIO_AUDIO_DEBUG_RECORDING_MANAGER_H_
+
+#include <map>
+#include <memory>
+
+#include "base/callback.h"
+#include "base/files/file_path.h"
+#include "base/memory/weak_ptr.h"
+#include "base/threading/thread_checker.h"
+#include "media/audio/audio_debug_recording_helper.h"
+#include "media/audio/audio_file_writer.h"
+#include "media/base/audio_parameters.h"
+
+namespace base {
+class FilePath;
+class SingleThreadTaskRunner;
+}
+
+namespace media {
+
+class AudioDebugRecordingHelper;
+
+// TODO BEFORE COMMIT: Is this a good location for these?
+
+// Callback type to unregister an AudioDebugRecorder.
+using UnregisterAudioDebugRecorderCallback = base::Callback<void()>;

[Max Morin, 2017/01/26 17:49:42]

Should probably be a OnceCallback (but some technical limitations might make it
impossible right now).

[Henrik Grunell, 2017/01/27 16:07:23]

Good point. I'm not sure actually about limitations. It's "under development",
but still new code should use Once and Repeatable versions according to
documentation. I'm going to do that.

+
+// A wrapper for AudioDebugRecorder to be able to automatically unregister at
+// destruction.
+// TODO BEFORE COMMIT: I'm not too keen on this. It would be better to have a
+// single interface given to the converter. This could perhaps be incorporated
+// in the recorder interface, making it a base class that contains the
+// unregister callback. But that means the recoder/helper needs to know about
+// registation which is not good either. Alternatively, we could skip automatic
+// unregistration alltogether.
+struct AudioDebugRecorderWrapper {
+  AudioDebugRecorderWrapper(
+      std::unique_ptr<AudioDebugRecorder> recorder,
+      UnregisterAudioDebugRecorderCallback unregister_callback);
+  ~AudioDebugRecorderWrapper();
+
+  // The wrapped recorder.
+  std::unique_ptr<AudioDebugRecorder> recorder;
+
+  // Run by deleter to unregister recorder.
+  UnregisterAudioDebugRecorderCallback unregister_callback;
+};
+
+// Deleter for the wrapper. Runs the unregister callback before deleting.
+struct AudioDebugRecorderWrapperDeleter {
+  void operator()(AudioDebugRecorderWrapper* recorder_wrapper) {
+    recorder_wrapper->unregister_callback.Run();
+    delete recorder_wrapper;
+  }
+};
+
+using AudioDebugRecorderWrapperUniquePtr =

[Max Morin, 2017/01/26 17:49:43]

I'm reading this on the train so I may be completely off, but both wrapper and
uniqueptr seems excessive, the unique ptr with deleter is itself a wrapper.
Maybe all functionality can be in the deleter and this can just be
std::unique_ptr<AudioDebugRecorder, AudioDebugRecorderDeleter> and a factory
function somewhere that puts the callback in the deleter?

Actually, can't it just do it in the destructor?

[o1ka, 2017/01/27 09:25:26]

Agree.

[Henrik Grunell, 2017/01/27 16:07:23]

Removed the wrapper. The helper takes an on destruction closure now.

+    std::unique_ptr<AudioDebugRecorderWrapper,
+                    AudioDebugRecorderWrapperDeleter>;
+
+// Callback type to register an AudioDebugRecorder. Returns an
+// AudioDebugRecorderWrapperUniquePtr which automatically unregisters the
+// recorder at destruction.
+using RegisterDebugRecordingSourceCallback =
+    base::RepeatingCallback<AudioDebugRecorderWrapperUniquePtr(
+        const AudioParameters&)>;
+
+// A manager for audio debug recording that handles registration of data
+// sources and hands them a recorder (AudioDebugRecordingHelper) to feed data
+// to, wrapped so that it unregisters automatically when deleted. When debug
+// recording is enabled, it is enabled on all recorders. It handles constructing
+// a file name for each recorder.
+class AudioDebugRecordingManager {
+ public:
+  explicit AudioDebugRecordingManager(
+      CreateAudioFileWriterCallback create_audio_file_writer_callback,
+      const std::string& file_name_extension,
+      scoped_refptr<base::SingleThreadTaskRunner> task_runner);
+  ~AudioDebugRecordingManager();
+
+  // Enables and disables debug recording.
+  void EnableDebugRecording(const base::FilePath& base_file_name);
+  void DisableDebugRecording();
+
+  // Registers a source and returns a wrapped recorder.
+  AudioDebugRecorderWrapperUniquePtr RegisterDebugRecordingSource(
+      const AudioParameters& params);
+
+ private:
+  // Map type from source id to recorder.
+  using DebugRecordingHelperMap = std::map<int, AudioDebugRecordingHelper*>;
+
+  // Unregisters a source. Stops recording on it's recorder.

[Max Morin, 2017/01/26 17:49:43]

its

[Henrik Grunell, 2017/01/27 16:07:23]

Removed that sentence.

+  void UnregisterDebugRecordingSource(int id);
+
+  // Returns |file_name| with |file_name_extension_| and |id| added to it as
+  // as extensions.
+  base::FilePath GetOutputDebugRecordingFileNameWithExtensions(
+      const base::FilePath& file_name,
+      int id);
+
+  // Recorders, one per source.
+  DebugRecordingHelperMap debug_recording_helpers_;
+
+  // Callback for creating AudioFileWriter objects.
+  const CreateAudioFileWriterCallback create_audio_file_writer_callback_;
+
+  // The base file name for debug recording files. If this is non-empty, debug
+  // recording is enabled.
+  base::FilePath debug_recording_base_file_name_;
+
+  // File name extension that will be added to the base file name.
+  const std::string file_name_extension_;
+
+  // The task runner this class lives on. Also handed to
+  // AudioDebugRecordingHelpers.
+  scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
+
+  base::ThreadChecker thread_checker_;
+  DISALLOW_COPY_AND_ASSIGN(AudioDebugRecordingManager);
+};
+
+}  // namespace media
+
+#endif  // MEDIA_AUDIO_AUDIO_DEBUG_RECORDING_MANAGER_H_