AudioRecord client threading cleanup

Rename ClientRecordThread to AudioRecordThread to be more similar to
AudioTrack naming.

Only create the thread once, and use resume() and pause() for start()
and stop().  This will allow us to have a known client callback thread
tid that we can pass to AudioFlinger before start().

mActive:
Made mActive a bool not int.
mActive is protected by mLock; volatile is meaningless.
Fixed a few places where mActive was accessed without a lock:
 - stopped()
 - processAudioBuffer()
These aren't used internally, so no need for _l() versions.

Change-Id: I4b8a5c90f3a22d3894b344564cb1c5aef4f1fda2

1 files changed, 19 insertions, 8 deletions

diff --git a/include/media/AudioRecord.h b/include/media/AudioRecord.h
index 01ab8c7..f7ebd39 100644
--- a/include/media/AudioRecord.h
+++ b/include/media/AudioRecord.h
@@ -316,18 +316,31 @@ private:
             AudioRecord& operator = (const AudioRecord& other);
 
     /* a small internal class to handle the callback */
-    class ClientRecordThread : public Thread
+    class AudioRecordThread : public Thread
     {
     public:
-        ClientRecordThread(AudioRecord& receiver, bool bCanCallJava = false);
+        AudioRecordThread(AudioRecord& receiver, bool bCanCallJava = false);
+
+        // Do not call Thread::requestExitAndWait() without first calling requestExit().
+        // Thread::requestExitAndWait() is not virtual, and the implementation doesn't do enough.
+        virtual void        requestExit();
+
+                void        pause();    // suspend thread from execution at next loop boundary
+                void        resume();   // allow thread to execute, if not requested to exit
+
     private:
         friend class AudioRecord;
         virtual bool        threadLoop();
-        virtual status_t    readyToRun();
         AudioRecord& mReceiver;
+        virtual ~AudioRecordThread();
+        Mutex               mMyLock;    // Thread::mLock is private
+        Condition           mMyCond;    // Thread::mThreadExitedCondition is private
+        bool                mPaused;    // whether thread is currently paused
     };
 
-            bool processAudioBuffer(const sp<ClientRecordThread>& thread);
+            // body of AudioRecordThread::threadLoop()
+            bool processAudioBuffer(const sp<AudioRecordThread>& thread);
+
             status_t openRecord_l(uint32_t sampleRate,
                                 audio_format_t format,
                                 audio_channel_mask_t channelMask,
@@ -336,12 +349,10 @@ private:
             audio_io_handle_t getInput_l();
             status_t restoreRecord_l(audio_track_cblk_t*& cblk);
 
-    sp<ClientRecordThread>  mClientRecordThread;
-    status_t                mReadyToRun;
+    sp<AudioRecordThread>   mAudioRecordThread;
     mutable Mutex           mLock;
-    Condition               mCondition;
 
-    volatile int32_t        mActive;
+    bool                    mActive;            // protected by mLock
 
     // for client callback handler
     callback_t              mCbf;