Tracks all open input streams in AudioManagerBase.

media/audio/audio_manager_base.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_AUDIO_MANAGER_BASE_H_
 #define MEDIA_AUDIO_AUDIO_MANAGER_BASE_H_
 
 #include <memory>
 #include <string>
+#include <unordered_set>
 #include <utility>
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "base/memory/scoped_vector.h"
 #include "base/observer_list.h"
 #include "base/threading/thread.h"
 #include "build/build_config.h"
 #include "media/audio/audio_manager.h"
 #include "media/audio/audio_output_dispatcher.h"
@@ skipping 70 matching lines @@
   // Creates the input stream for the |AUDIO_PCM_LOW_LATENCY| format.
   virtual AudioInputStream* MakeLowLatencyInputStream(
       const AudioParameters& params,
       const std::string& device_id,
       const LogCallback& log_callback) = 0;
 
   std::string GetGroupIDOutput(const std::string& output_device_id) override;
   std::string GetGroupIDInput(const std::string& input_device_id) override;
 
   // Get number of input or output streams.
-  int input_stream_count() const { return num_input_streams_; }
+  int input_stream_count() const {
+    return static_cast<int>(input_streams_.size());
+  }
   int output_stream_count() const { return num_output_streams_; }
 
  protected:
   AudioManagerBase(
       scoped_refptr<base::SingleThreadTaskRunner> task_runner,
       scoped_refptr<base::SingleThreadTaskRunner> worker_task_runner,
       AudioLogFactory* audio_log_factory);
 
   // Releases all the audio output dispatchers.
   // All audio streams should be closed before Shutdown() is called.
@@ skipping 36 matching lines @@
   // Max number of open output streams, modified by
   // SetMaxOutputStreamsAllowed().
   int max_num_output_streams_;
 
   // Max number of open input streams.
   int max_num_input_streams_;
 
   // Number of currently open output streams.
   int num_output_streams_;
 
-  // Number of currently open input streams.
-  int num_input_streams_;
-
   // Track output state change listeners.
   base::ObserverList<AudioDeviceListener> output_listeners_;
 
+  // Contains currently open input streams.
+  std::unordered_set<AudioInputStream*> input_streams_;
+
   // Map of cached AudioOutputDispatcher instances.  Must only be touched
   // from the audio thread (no locking).
   AudioOutputDispatchers output_dispatchers_;
 
   // Proxy for creating AudioLog objects.
   AudioLogFactory* const audio_log_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioManagerBase);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_AUDIO_AUDIO_MANAGER_BASE_H_