Fixed audio buffer lifecycle and implemented audio shutdown

android-project/src/org/libsdl/app/SDLActivity.java

@@ -139,7 +139,7 @@ public class SDLActivity extends Activity {
                 i += result;
             } else if (result == 0) {
                 try {
-                    Thread.sleep(10);
+                    Thread.sleep(1);
                 } catch(InterruptedException e) {
                     // Nom nom
                 }
@@ -157,7 +157,7 @@ public class SDLActivity extends Activity {
                 i += result;
             } else if (result == 0) {
                 try {
-                    Thread.sleep(10);
+                    Thread.sleep(1);
                 } catch(InterruptedException e) {
                     // Nom nom
                 }
@@ -168,6 +168,23 @@ public class SDLActivity extends Activity {
         }
     }
 
+    public static void audioQuit() {
+        if (mAudioThread != null) {
+            try {
+                mAudioThread.join();
+            } catch(Exception e) {
+                Log.v("SDL", "Problem stopping audio thread: " + e);
+            }
+            mAudioThread = null;
+
+            Log.v("SDL", "Finished waiting for audio thread");
+        }
+
+        if (mAudioTrack != null) {
+            mAudioTrack.stop();
+            mAudioTrack = null;
+        }
+    }
 }
 
 /**
@@ -233,13 +250,11 @@ class SDLSurface extends SurfaceView implements SurfaceHolder.Callback,
 
         // Now wait for the SDL thread to quit
         if (mSDLThread != null) {
-            //synchronized (mSDLThread) {
             try {
                 mSDLThread.join();
             } catch(Exception e) {
                 Log.v("SDL", "Problem stopping thread: " + e);
             }
-            //}
             mSDLThread = null;
 
             //Log.v("SDL", "Finished waiting for SDL thread");

src/SDL_android.cpp

@@ -55,6 +55,7 @@ static jmethodID midFlipBuffers;
 static jmethodID midAudioInit;
 static jmethodID midAudioWriteShortBuffer;
 static jmethodID midAudioWriteByteBuffer;
+static jmethodID midAudioQuit;
 
 // Accelerometer data storage
 float fLastAccelerometer[3];
@@ -86,9 +87,10 @@ extern "C" void SDL_Android_Init(JNIEnv* env)
     midAudioInit = mEnv->GetStaticMethodID(cls, "audioInit", "(IZZI)Ljava/lang/Object;");
     midAudioWriteShortBuffer = mEnv->GetStaticMethodID(cls, "audioWriteShortBuffer", "([S)V");
     midAudioWriteByteBuffer = mEnv->GetStaticMethodID(cls, "audioWriteByteBuffer", "([B)V");
+    midAudioQuit = mEnv->GetStaticMethodID(cls, "audioQuit", "()V");
 
     if(!midCreateGLContext || !midFlipBuffers || !midAudioInit ||
-       !midAudioWriteShortBuffer || !midAudioWriteByteBuffer) {
+       !midAudioWriteShortBuffer || !midAudioWriteByteBuffer || !midAudioQuit) {
         __android_log_print(ANDROID_LOG_WARN, "SDL", "SDL: Couldn't locate Java callbacks, check that they're named and typed correctly");
     }
 }
@@ -171,78 +173,69 @@ extern "C" void Android_JNI_SwapWindow()
 //
 // Audio support
 //
-static jint audioBufferFrames = 0;
+static jboolean audioBuffer16Bit = JNI_FALSE;
-static bool audioBuffer16Bit = false;
+static jboolean audioBufferStereo = JNI_FALSE;
-static bool audioBufferStereo = false;
+static jobject audioBuffer = NULL;
-
+static void* audioBufferPinned = NULL;
-static jobject audioBuffer;
-static void * audioPinnedBuffer;
 
 extern "C" int Android_JNI_OpenAudioDevice(int sampleRate, int is16Bit, int channelCount, int desiredBufferFrames)
 {
+    int audioBufferFrames;
+
     __android_log_print(ANDROID_LOG_VERBOSE, "SDL", "SDL audio: opening device");
     audioBuffer16Bit = is16Bit;
     audioBufferStereo = channelCount > 1;
 
     audioBuffer = mEnv->CallStaticObjectMethod(mActivityInstance, midAudioInit, sampleRate, audioBuffer16Bit, audioBufferStereo, desiredBufferFrames);
-	audioBuffer = mEnv->NewGlobalRef(audioBuffer);
 
     if (audioBuffer == NULL) {
         __android_log_print(ANDROID_LOG_WARN, "SDL", "SDL audio: didn't get back a good audio buffer!");
         return 0;
     }
+    audioBuffer = mEnv->NewGlobalRef(audioBuffer);
 
-	if (audioBufferStereo) {
+    jboolean isCopy = JNI_FALSE;
-		audioBufferFrames = mEnv->GetArrayLength((jshortArray)audioBuffer) / 2;
+    if (audioBuffer16Bit) {
+        audioBufferPinned = mEnv->GetShortArrayElements((jshortArray)audioBuffer, &isCopy);
+        audioBufferFrames = mEnv->GetArrayLength((jshortArray)audioBuffer);
     } else {
+        audioBufferPinned = mEnv->GetByteArrayElements((jbyteArray)audioBuffer, &isCopy);
         audioBufferFrames = mEnv->GetArrayLength((jbyteArray)audioBuffer);
     }
+    if (audioBufferStereo) {
+        audioBufferFrames /= 2;
+    }
 
     return audioBufferFrames;
 }
 
-extern "C" void * Android_JNI_PinAudioBuffer()
+extern "C" void * Android_JNI_GetAudioBuffer()
 {
-	jboolean isCopy = JNI_FALSE;
+    //jboolean isCopy = JNI_FALSE;
-
+    //audioBufferPinned = mAudioEnv->GetPrimitiveArrayCritical((jarray)audioBuffer, &isCopy);
-	if (audioPinnedBuffer != NULL) {
+    return audioBufferPinned;
-		return audioPinnedBuffer;
 }
 
-	if (audioBuffer16Bit) {
+extern "C" void Android_JNI_WriteAudioBuffer()
-		audioPinnedBuffer = mAudioEnv->GetShortArrayElements((jshortArray)audioBuffer, &isCopy);
-	} else {
-		audioPinnedBuffer = mAudioEnv->GetByteArrayElements((jbyteArray)audioBuffer, &isCopy);
-	}
-
-	return audioPinnedBuffer;
-}
-
-extern "C" void Android_JNI_WriteAudioBufferAndUnpin()
 {
-	if (audioPinnedBuffer == NULL) {
+    //mAudioEnv->ReleasePrimitiveArrayCritical((jarray)audioBuffer, audioBufferPinned, 0);
-		return;
-	}
-
     if (audioBuffer16Bit) {
-		mAudioEnv->ReleaseShortArrayElements((jshortArray)audioBuffer, (jshort *)audioPinnedBuffer, JNI_COMMIT);
+        mAudioEnv->ReleaseShortArrayElements((jshortArray)audioBuffer, (jshort *)audioBufferPinned, JNI_COMMIT);
         mAudioEnv->CallStaticVoidMethod(mActivityInstance, midAudioWriteShortBuffer, (jshortArray)audioBuffer);
     } else {
-		mAudioEnv->ReleaseByteArrayElements((jbyteArray)audioBuffer, (jbyte *)audioPinnedBuffer, JNI_COMMIT);
+        mAudioEnv->ReleaseByteArrayElements((jbyteArray)audioBuffer, (jbyte *)audioBufferPinned, JNI_COMMIT);
         mAudioEnv->CallStaticVoidMethod(mActivityInstance, midAudioWriteByteBuffer, (jbyteArray)audioBuffer);
     }
 
-	audioPinnedBuffer = NULL;
+    /* JNI_COMMIT means the changes are committed to the VM but the buffer remains pinned */
 }
 
 extern "C" void Android_JNI_CloseAudioDevice()
 {
-    if (audioBuffer) {
+    mEnv->CallStaticVoidMethod(mActivityInstance, midAudioQuit); 
+
     mEnv->DeleteGlobalRef(audioBuffer);
     audioBuffer = NULL;
 }
 
-	// TODO: Implement
-}
-
 /* vi: set ts=4 sw=4 expandtab: */

src/SDL_android.h

@@ -34,8 +34,8 @@ void Android_JNI_SwapWindow();
 
 // Audio support
 int Android_JNI_OpenAudioDevice(int sampleRate, int is16Bit, int channelCount, int desiredBufferFrames);
-void* Android_JNI_PinAudioBuffer();
+void* Android_JNI_GetAudioBuffer();
-void Android_JNI_WriteAudioBufferAndUnpin();
+void Android_JNI_WriteAudioBuffer();
 void Android_JNI_CloseAudioDevice();
 
 /* Ends C function definitions when using C++ */

src/audio/android/SDL_androidaudio.c

@@ -103,26 +103,19 @@ AndroidAUD_OpenDevice(_THIS, const char *devname, int iscapture)
 static void
 AndroidAUD_PlayDevice(_THIS)
 {
-    Android_JNI_WriteAudioBufferAndUnpin();
+    Android_JNI_WriteAudioBuffer();
-    this->hidden->mixbuf = NULL;
 }
 
 static Uint8 *
 AndroidAUD_GetDeviceBuf(_THIS)
 {
-	if (this->hidden->mixbuf == NULL) {
+    return Android_JNI_GetAudioBuffer();
-		this->hidden->mixbuf = Android_JNI_PinAudioBuffer();
-	}
-    return this->hidden->mixbuf;
 }
 
 static void
 AndroidAUD_CloseDevice(_THIS)
 {
     if (this->hidden != NULL) {
-    	if (this->hidden->mixbuf != NULL) {
-    		Android_JNI_WriteAudioBufferAndUnpin();
-    	}
     	SDL_free(this->hidden);
     	this->hidden = NULL;
     }

src/audio/android/SDL_androidaudio.h

@@ -31,9 +31,6 @@
 
 struct SDL_PrivateAudioData
 {
-    /* The file descriptor for the audio device */
-    Uint8 *mixbuf;
-    Uint32 mixlen;
 };
 
 #endif /* _SDL_androidaudio_h */