1 files changed, 125 insertions, 0 deletions
diff --git a/chrome/browser/chromeos/pulse_audio_mixer.h b/chrome/browser/chromeos/pulse_audio_mixer.h
new file mode 100644
index 0000000..223fe33
--- /dev/null
+++ b/chrome/browser/chromeos/pulse_audio_mixer.h
@@ -0,0 +1,125 @@
+// Copyright (c) 2010 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 CHROME_BROWSER_CHROMEOS_PULSE_AUDIO_MIXER_H_
+#define CHROME_BROWSER_CHROMEOS_PULSE_AUDIO_MIXER_H_
+
+#include "base/basictypes.h"
+#include "base/callback.h"
+#include "base/scoped_ptr.h"
+#include "base/thread.h"
+
+struct pa_context;
+struct pa_cvolume;
+struct pa_threaded_mainloop;
+struct pa_operation;
+struct pa_sink_info;
+
+namespace chromeos {
+
+class PulseAudioMixer {
+ public:
+  PulseAudioMixer();
+  ~PulseAudioMixer();
+
+  // Non-blocking, connect to PulseAudio and find a default device, and call
+  // callback when complete with success code.
+  typedef Callback1<bool>::Type InitDoneCallback;
+  bool Init(InitDoneCallback* callback);
+
+  // Blocking call. Returns a default of -inf on error.
+  double GetVolumeDb() const;
+
+  // Non-blocking, volume sent in as first param to callback
+  typedef Callback2<double, void*>::Type GetVolumeCallback;
+  void GetVolumeDbAsync(GetVolumeCallback* callback, void* user);
+
+  // Non-blocking call.
+  void SetVolumeDb(double vol_db);
+
+  // Gets the mute state of the default device (true == mute). Blocking call.
+  // Returns a default of false on error.
+  bool IsMute() const;
+
+  // Non-Blocking call.
+  void SetMute(bool mute);
+
+  // Call any time to see if we have a valid working connection to PulseAudio.
+  // Non-blocking call.
+  bool IsValid() const;
+
+ private:
+  struct AudioInfo;
+
+  enum State {
+    UNINITIALIZED = 0,
+    INITIALIZING,
+    READY,
+    SHUTTING_DOWN
+  };
+
+  // These are the tasks to be run in the background on the worker thread.
+  void DoInit(InitDoneCallback* callback);
+  void DoGetVolume(GetVolumeCallback* callback, void* user);
+
+  static void ConnectToPulseCallbackThunk(pa_context* c, void* userdata);
+  void OnConnectToPulseCallback(pa_context* c, bool* connect_done);
+
+  // This goes through sequence of connecting to the default PulseAudio server.
+  // We will block until we either have a valid connection or something failed.
+  // If a connection is lost for some reason, delete and recreate the object.
+  bool PulseAudioInit();
+
+  // PulseAudioFree.  Disconnect from server.
+  void PulseAudioFree();
+
+  // Check if the PA system is ready for communication, as well as if a default
+  // device is available to talk to.  This can return false if we lose the
+  // connection, even after an original successful init.
+  bool PulseAudioValid() const;
+
+  // Iterates the PA mainloop and only returns once an operation has completed
+  // (successfully or unsuccessfully).  This call only blocks the worker thread.
+  void CompleteOperationAndUnlock(pa_operation* pa_op) const;
+
+  // For now, this just gets the first device returned from the enumeration
+  // request.  This will be the 'default' or 'master' device that all further
+  // actions are taken on.  Blocking call.
+  void GetDefaultPlaybackDevice();
+  static void EnumerateDevicesCallback(pa_context* unused,
+                                       const pa_sink_info* sink_info,
+                                       int eol,
+                                       void* userdata);
+  void OnEnumerateDevices(const pa_sink_info* sink_info, int eol);
+
+  // Get the info we're interested in from the default device. Currently this
+  // is an array of volumes, and the mute state.  Blocking call.
+  void GetAudioInfo(AudioInfo* info) const;
+  static void GetAudioInfoCallback(pa_context* unused,
+                                   const pa_sink_info* sink_info,
+                                   int eol,
+                                   void* userdata);
+
+  // The PulseAudio index of the main device being used.
+  mutable int device_id_;
+
+  // Set to the number of channels on the main device.
+  int last_channels_;
+  State mixer_state_;
+
+  // Cached contexts for use in PulseAudio calls.
+  pa_context* pa_context_;
+  pa_threaded_mainloop* pa_mainloop_;
+
+  scoped_ptr<base::Thread> thread_;
+
+  DISALLOW_COPY_AND_ASSIGN(PulseAudioMixer);
+};
+
+}  // namespace chromeos
+
+DISABLE_RUNNABLE_METHOD_REFCOUNT(chromeos::PulseAudioMixer);
+
+#endif  // CHROME_BROWSER_CHROMEOS_PULSE_AUDIO_MIXER_H_
+