Android audio device selection (#6824)

Make it possible to select a specific audio device for Android

android-project/app/src/main/java/org/libsdl/app/SDL.java

@@ -29,6 +29,7 @@ public class SDL {
 
     // This function stores the current activity (SDL or not)
     public static void setContext(Context context) {
+        SDLAudioManager.setContext(context);
         mContext = context;
     }
 

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

@@ -393,7 +393,7 @@ public class SDLActivity extends Activity implements View.OnSystemUiVisibilityCh
         mHIDDeviceManager = HIDDeviceManager.acquire(this);
 
         // Set up the surface
-        mSurface = createSDLSurface(getApplication());
+        mSurface = createSDLSurface(this);
 
         mLayout = new RelativeLayout(this);
         mLayout.addView(mSurface);
@@ -588,6 +588,8 @@ public class SDLActivity extends Activity implements View.OnSystemUiVisibilityCh
             mHIDDeviceManager = null;
         }
 
+        SDLAudioManager.release(this);
+
         if (SDLActivity.mBrokenLibraries) {
            super.onDestroy();
            return;

android-project/app/src/main/java/org/libsdl/app/SDLAudioManager.java

@@ -1,5 +1,8 @@
 package org.libsdl.app;
 
+import android.content.Context;
+import android.media.AudioDeviceCallback;
+import android.media.AudioDeviceInfo;
 import android.media.AudioFormat;
 import android.media.AudioManager;
 import android.media.AudioRecord;
@@ -8,34 +11,59 @@ import android.media.MediaRecorder;
 import android.os.Build;
 import android.util.Log;
 
-public class SDLAudioManager
-{
+import java.util.Arrays;
+
+public class SDLAudioManager {
     protected static final String TAG = "SDLAudio";
 
     protected static AudioTrack mAudioTrack;
     protected static AudioRecord mAudioRecord;
+    protected static Context mContext;
+
+    private static final AudioDeviceCallback mAudioDeviceCallback = new AudioDeviceCallback() {
+        @Override
+        public void onAudioDevicesAdded(AudioDeviceInfo[] addedDevices) {
+            Arrays.stream(addedDevices).forEach(deviceInfo -> addAudioDevice(deviceInfo.isSink(), deviceInfo.getId()));
+        }
+
+        @Override
+        public void onAudioDevicesRemoved(AudioDeviceInfo[] removedDevices) {
+            Arrays.stream(removedDevices).forEach(deviceInfo -> removeAudioDevice(deviceInfo.isSink(), deviceInfo.getId()));
+        }
+    };
 
     public static void initialize() {
         mAudioTrack = null;
         mAudioRecord = null;
     }
 
+    public static void setContext(Context context) {
+        mContext = context;
+        if (context != null) {
+            registerAudioDeviceCallback();
+        }
+    }
+
+    public static void release(Context context) {
+        unregisterAudioDeviceCallback(context);
+    }
+
     // Audio
 
     protected static String getAudioFormatString(int audioFormat) {
         switch (audioFormat) {
-        case AudioFormat.ENCODING_PCM_8BIT:
-            return "8-bit";
-        case AudioFormat.ENCODING_PCM_16BIT:
-            return "16-bit";
-        case AudioFormat.ENCODING_PCM_FLOAT:
-            return "float";
-        default:
-            return Integer.toString(audioFormat);
+            case AudioFormat.ENCODING_PCM_8BIT:
+                return "8-bit";
+            case AudioFormat.ENCODING_PCM_16BIT:
+                return "16-bit";
+            case AudioFormat.ENCODING_PCM_FLOAT:
+                return "float";
+            default:
+                return Integer.toString(audioFormat);
         }
     }
 
-    protected static int[] open(boolean isCapture, int sampleRate, int audioFormat, int desiredChannels, int desiredFrames) {
+    protected static int[] open(boolean isCapture, int sampleRate, int audioFormat, int desiredChannels, int desiredFrames, int deviceId) {
         int channelConfig;
         int sampleSize;
         int frameSize;
@@ -201,6 +229,10 @@ public class SDLAudioManager
                     return null;
                 }
 
+                if (deviceId != 0) {
+                    mAudioRecord.setPreferredDevice(getOutputAudioDeviceInfo(deviceId));
+                }
+
                 mAudioRecord.startRecording();
             }
 
@@ -224,6 +256,10 @@ public class SDLAudioManager
                     return null;
                 }
 
+                if (deviceId != 0) {
+                    mAudioTrack.setPreferredDevice(getInputAudioDeviceInfo(deviceId));
+                }
+
                 mAudioTrack.play();
             }
 
@@ -238,11 +274,53 @@ public class SDLAudioManager
         return results;
     }
 
+    private static AudioDeviceInfo getInputAudioDeviceInfo(int deviceId) {
+        AudioManager audioManager = (AudioManager) mContext.getSystemService(Context.AUDIO_SERVICE);
+        return Arrays.stream(audioManager.getDevices(AudioManager.GET_DEVICES_INPUTS))
+                .filter(deviceInfo -> deviceInfo.getId() == deviceId)
+                .findFirst()
+                .orElse(null);
+    }
+
+    private static AudioDeviceInfo getOutputAudioDeviceInfo(int deviceId) {
+        AudioManager audioManager = (AudioManager) mContext.getSystemService(Context.AUDIO_SERVICE);
+        return Arrays.stream(audioManager.getDevices(AudioManager.GET_DEVICES_OUTPUTS))
+                .filter(deviceInfo -> deviceInfo.getId() == deviceId)
+                .findFirst()
+                .orElse(null);
+    }
+
+    private static void registerAudioDeviceCallback() {
+        AudioManager audioManager = (AudioManager) mContext.getSystemService(Context.AUDIO_SERVICE);
+        audioManager.registerAudioDeviceCallback(mAudioDeviceCallback, null);
+    }
+
+    private static void unregisterAudioDeviceCallback(Context context) {
+        AudioManager audioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);
+        audioManager.unregisterAudioDeviceCallback(mAudioDeviceCallback);
+    }
+
+    /**
+     * This method is called by SDL using JNI.
+     */
+    public static int[] getAudioOutputDevices() {
+        AudioManager audioManager = (AudioManager) mContext.getSystemService(Context.AUDIO_SERVICE);
+        return Arrays.stream(audioManager.getDevices(AudioManager.GET_DEVICES_OUTPUTS)).mapToInt(AudioDeviceInfo::getId).toArray();
+    }
+
+    /**
+     * This method is called by SDL using JNI.
+     */
+    public static int[] getAudioInputDevices() {
+        AudioManager audioManager = (AudioManager) mContext.getSystemService(Context.AUDIO_SERVICE);
+        return Arrays.stream(audioManager.getDevices(AudioManager.GET_DEVICES_INPUTS)).mapToInt(AudioDeviceInfo::getId).toArray();
+    }
+
     /**
      * This method is called by SDL using JNI.
      */
-    public static int[] audioOpen(int sampleRate, int audioFormat, int desiredChannels, int desiredFrames) {
-        return open(false, sampleRate, audioFormat, desiredChannels, desiredFrames);
+    public static int[] audioOpen(int sampleRate, int audioFormat, int desiredChannels, int desiredFrames, int deviceId) {
+        return open(false, sampleRate, audioFormat, desiredChannels, desiredFrames, deviceId);
     }
 
     /**
@@ -326,8 +404,8 @@ public class SDLAudioManager
     /**
      * This method is called by SDL using JNI.
      */
-    public static int[] captureOpen(int sampleRate, int audioFormat, int desiredChannels, int desiredFrames) {
-        return open(true, sampleRate, audioFormat, desiredChannels, desiredFrames);
+    public static int[] captureOpen(int sampleRate, int audioFormat, int desiredChannels, int desiredFrames, int deviceId) {
+        return open(true, sampleRate, audioFormat, desiredChannels, desiredFrames, deviceId);
     }
 
     /** This method is called by SDL using JNI. */
@@ -391,4 +469,9 @@ public class SDLAudioManager
     }
 
     public static native int nativeSetupJNI();
+
+    public static native void removeAudioDevice(boolean isCapture, int deviceId);
+
+    public static native void addAudioDevice(boolean isCapture, int deviceId);
+
 }

include/SDL_surface.h

@@ -683,7 +683,7 @@ extern DECLSPEC SDL_Surface *SDLCALL SDL_ConvertSurface
  * it might be easier to call but it doesn't have access to palette
  * information for the destination surface, in case that would be important.
  *
- * \param surface the existing SDL_Surface structure to convert
+ * \param src the existing SDL_Surface structure to convert
  * \param pixel_format the SDL_PixelFormatEnum that the new surface is
  *                     optimized for
  * \param flags the flags are unused and should be set to 0; this is a

src/audio/aaudio/SDL_aaudio.c

@@ -70,6 +70,45 @@ void aaudio_errorCallback(AAudioStream *stream, void *userData, aaudio_result_t
 
 #define LIB_AAUDIO_SO "libaaudio.so"
 
+static void aaudio_DetectDevices(void)
+{
+    int *inputs;
+    inputs = SDL_malloc(sizeof(int) * 100);
+    SDL_zerop(inputs);
+    int inputs_length = 0;
+
+    Android_JNI_GetAudioInputDevices(inputs, &inputs_length);
+
+    for (int i = 0; i < inputs_length; ++i) {
+        int device_id = inputs[i];
+        int n = (int) (log10(device_id) + 1);
+        char device_name[n];
+        SDL_itoa(device_id, device_name, 10);
+        SDL_Log("Adding input device with name %s", device_name);
+        SDL_AddAudioDevice(SDL_FALSE, SDL_strdup(device_name), NULL, (void *) ((size_t) device_id + 1));
+    }
+
+    SDL_free(inputs);
+
+    int *outputs;
+    outputs = SDL_malloc(sizeof(int) * 100);
+    SDL_zerop(outputs);
+    int outputs_length = 0;
+
+    Android_JNI_GetAudioOutputDevices(outputs, &outputs_length);
+
+    for (int i = 0; i < outputs_length; ++i) {
+        int device_id = outputs[i];
+        int n = (int) (log10(device_id) + 1);
+        char device_name[n];
+        SDL_itoa(device_id, device_name, 10);
+        SDL_Log("Adding output device with name %s", device_name);
+        SDL_AddAudioDevice(SDL_TRUE, SDL_strdup(device_name), NULL, (void *) ((size_t) device_id + 1));
+    }
+
+    SDL_free(outputs);
+}
+
 static int aaudio_OpenDevice(_THIS, const char *devname)
 {
     struct SDL_PrivateAudioData *private;
@@ -101,6 +140,11 @@ static int aaudio_OpenDevice(_THIS, const char *devname)
 
     ctx.AAudioStreamBuilder_setSampleRate(ctx.builder, this->spec.freq);
     ctx.AAudioStreamBuilder_setChannelCount(ctx.builder, this->spec.channels);
+    if(devname != NULL) {
+        int aaudio_device_id = SDL_atoi(devname);
+        LOGI("Opening device id %d", aaudio_device_id);
+        ctx.AAudioStreamBuilder_setDeviceId(ctx.builder, aaudio_device_id);
+    }
     {
         aaudio_direction_t direction = (iscapture ? AAUDIO_DIRECTION_INPUT : AAUDIO_DIRECTION_OUTPUT);
         ctx.AAudioStreamBuilder_setDirection(ctx.builder, direction);
@@ -300,17 +344,19 @@ static SDL_bool aaudio_Init(SDL_AudioDriverImpl *impl)
         goto failure;
     }
 
+    impl->DetectDevices = aaudio_DetectDevices;
     impl->Deinitialize = aaudio_Deinitialize;
     impl->OpenDevice = aaudio_OpenDevice;
     impl->CloseDevice = aaudio_CloseDevice;
     impl->PlayDevice = aaudio_PlayDevice;
     impl->GetDeviceBuf = aaudio_GetDeviceBuf;
     impl->CaptureFromDevice = aaudio_CaptureFromDevice;
+    impl->AllowsArbitraryDeviceNames = SDL_TRUE;
 
     /* and the capabilities */
     impl->HasCaptureSupport = SDL_TRUE;
-    impl->OnlyHasDefaultOutputDevice = SDL_TRUE;
-    impl->OnlyHasDefaultCaptureDevice = SDL_TRUE;
+    impl->OnlyHasDefaultOutputDevice = SDL_FALSE;
+    impl->OnlyHasDefaultCaptureDevice = SDL_FALSE;
 
     /* this audio target is available. */
     LOGI("SDL aaudio_Init OK");

src/audio/aaudio/SDL_aaudiofuncs.h

@@ -24,7 +24,7 @@
 SDL_PROC(const char *, AAudio_convertResultToText, (aaudio_result_t returnCode))
 SDL_PROC(const char *, AAudio_convertStreamStateToText, (aaudio_stream_state_t state))
 SDL_PROC(aaudio_result_t, AAudio_createStreamBuilder, (AAudioStreamBuilder * *builder))
-SDL_PROC_UNUSED(void, AAudioStreamBuilder_setDeviceId, (AAudioStreamBuilder * builder, int32_t deviceId))
+SDL_PROC(void, AAudioStreamBuilder_setDeviceId, (AAudioStreamBuilder * builder, int32_t deviceId))
 SDL_PROC(void, AAudioStreamBuilder_setSampleRate, (AAudioStreamBuilder * builder, int32_t sampleRate))
 SDL_PROC(void, AAudioStreamBuilder_setChannelCount, (AAudioStreamBuilder * builder, int32_t channelCount))
 SDL_PROC_UNUSED(void, AAudioStreamBuilder_setSamplesPerFrame, (AAudioStreamBuilder * builder, int32_t samplesPerFrame))

src/audio/android/SDL_androidaudio.c

@@ -35,6 +35,44 @@
 static SDL_AudioDevice *audioDevice = NULL;
 static SDL_AudioDevice *captureDevice = NULL;
 
+static void ANDROIDAUDIO_DetectDevices(void) {
+    int *inputs;
+    inputs = SDL_malloc(sizeof(int) * 100);
+    SDL_zerop(inputs);
+    int inputs_length = 0;
+
+    Android_JNI_GetAudioInputDevices(inputs, &inputs_length);
+
+    for (int i = 0; i < inputs_length; ++i) {
+        int device_id = inputs[i];
+        int n = (int) (log10(device_id) + 1);
+        char device_name[n];
+        SDL_itoa(device_id, device_name, 10);
+        SDL_Log("Adding input device with name %s", device_name);
+        SDL_AddAudioDevice(SDL_FALSE, SDL_strdup(device_name), NULL, (void *) ((size_t) device_id + 1));
+    }
+
+    SDL_free(inputs);
+
+    int *outputs;
+    outputs = SDL_malloc(sizeof(int) * 100);
+    SDL_zerop(outputs);
+    int outputs_length = 0;
+
+    Android_JNI_GetAudioOutputDevices(outputs, &outputs_length);
+
+    for (int i = 0; i < outputs_length; ++i) {
+        int device_id = outputs[i];
+        int n = (int) (log10(device_id) + 1);
+        char device_name[n];
+        SDL_itoa(device_id, device_name, 10);
+        SDL_Log("Adding output device with name %s", device_name);
+        SDL_AddAudioDevice(SDL_TRUE, SDL_strdup(device_name), NULL, (void *) ((size_t) device_id + 1));
+    }
+
+    SDL_free(outputs);
+}
+
 static int ANDROIDAUDIO_OpenDevice(_THIS, const char *devname)
 {
     SDL_AudioFormat test_format;
@@ -63,12 +101,18 @@ static int ANDROIDAUDIO_OpenDevice(_THIS, const char *devname)
         }
     }
 
+    int audio_device_id = 0;
+
+    if(devname != NULL) {
+        audio_device_id = SDL_atoi(devname);
+    }
+
     if (!test_format) {
         /* Didn't find a compatible format :( */
         return SDL_SetError("%s: Unsupported audio format", "android");
     }
 
-    if (Android_JNI_OpenAudioDevice(iscapture, &this->spec) < 0) {
+    if (Android_JNI_OpenAudioDevice(iscapture, audio_device_id, &this->spec) < 0) {
         return -1;
     }
 
@@ -116,17 +160,19 @@ static void ANDROIDAUDIO_CloseDevice(_THIS)
 static SDL_bool ANDROIDAUDIO_Init(SDL_AudioDriverImpl *impl)
 {
     /* Set the function pointers */
+    impl->DetectDevices = ANDROIDAUDIO_DetectDevices;
     impl->OpenDevice = ANDROIDAUDIO_OpenDevice;
     impl->PlayDevice = ANDROIDAUDIO_PlayDevice;
     impl->GetDeviceBuf = ANDROIDAUDIO_GetDeviceBuf;
     impl->CloseDevice = ANDROIDAUDIO_CloseDevice;
     impl->CaptureFromDevice = ANDROIDAUDIO_CaptureFromDevice;
     impl->FlushCapture = ANDROIDAUDIO_FlushCapture;
+    impl->AllowsArbitraryDeviceNames = SDL_TRUE;
 
     /* and the capabilities */
     impl->HasCaptureSupport = SDL_TRUE;
-    impl->OnlyHasDefaultOutputDevice = SDL_TRUE;
-    impl->OnlyHasDefaultCaptureDevice = SDL_TRUE;
+    impl->OnlyHasDefaultOutputDevice = SDL_FALSE;
+    impl->OnlyHasDefaultCaptureDevice = SDL_FALSE;
 
     return SDL_TRUE; /* this audio target is available. */
 }

src/core/android/SDL_android.c

@@ -221,8 +221,18 @@ static JNINativeMethod SDLInputConnection_tab[] = {
 JNIEXPORT void JNICALL SDL_JAVA_AUDIO_INTERFACE(nativeSetupJNI)(
     JNIEnv *env, jclass jcls);
 
+JNIEXPORT void JNICALL
+SDL_JAVA_AUDIO_INTERFACE(addAudioDevice)(JNIEnv *env, jclass jcls, jboolean is_capture,
+                                         jint device_id);
+
+JNIEXPORT void JNICALL
+SDL_JAVA_AUDIO_INTERFACE(removeAudioDevice)(JNIEnv *env, jclass jcls, jboolean is_capture,
+                                            jint device_id);
+
 static JNINativeMethod SDLAudioManager_tab[] = {
-    { "nativeSetupJNI", "()I", SDL_JAVA_AUDIO_INTERFACE(nativeSetupJNI) }
+    { "nativeSetupJNI", "()I", SDL_JAVA_AUDIO_INTERFACE(nativeSetupJNI) },
+    { "addAudioDevice", "(ZI)V", SDL_JAVA_AUDIO_INTERFACE(addAudioDevice) },
+    { "removeAudioDevice", "(ZI)V", SDL_JAVA_AUDIO_INTERFACE(removeAudioDevice) }
 };
 
 /* Java class SDLControllerManager */
@@ -330,6 +340,8 @@ static jmethodID midSupportsRelativeMouse;
 static jclass mAudioManagerClass;
 
 /* method signatures */
+static jmethodID midGetAudioOutputDevices;
+static jmethodID midGetAudioInputDevices;
 static jmethodID midAudioOpen;
 static jmethodID midAudioWriteByteBuffer;
 static jmethodID midAudioWriteShortBuffer;
@@ -655,8 +667,14 @@ JNIEXPORT void JNICALL SDL_JAVA_AUDIO_INTERFACE(nativeSetupJNI)(JNIEnv *env, jcl
 
     mAudioManagerClass = (jclass)((*env)->NewGlobalRef(env, cls));
 
+    midGetAudioOutputDevices = (*env)->GetStaticMethodID(env, mAudioManagerClass,
+                                                         "getAudioOutputDevices",
+                                                         "()[I");
+    midGetAudioInputDevices = (*env)->GetStaticMethodID(env, mAudioManagerClass,
+                                                        "getAudioInputDevices",
+                                                        "()[I");
     midAudioOpen = (*env)->GetStaticMethodID(env, mAudioManagerClass,
-                                             "audioOpen", "(IIII)[I");
+                                             "audioOpen", "(IIIII)[I");
     midAudioWriteByteBuffer = (*env)->GetStaticMethodID(env, mAudioManagerClass,
                                                         "audioWriteByteBuffer", "([B)V");
     midAudioWriteShortBuffer = (*env)->GetStaticMethodID(env, mAudioManagerClass,
@@ -666,7 +684,7 @@ JNIEXPORT void JNICALL SDL_JAVA_AUDIO_INTERFACE(nativeSetupJNI)(JNIEnv *env, jcl
     midAudioClose = (*env)->GetStaticMethodID(env, mAudioManagerClass,
                                               "audioClose", "()V");
     midCaptureOpen = (*env)->GetStaticMethodID(env, mAudioManagerClass,
-                                               "captureOpen", "(IIII)[I");
+                                               "captureOpen", "(IIIII)[I");
     midCaptureReadByteBuffer = (*env)->GetStaticMethodID(env, mAudioManagerClass,
                                                          "captureReadByteBuffer", "([BZ)I");
     midCaptureReadShortBuffer = (*env)->GetStaticMethodID(env, mAudioManagerClass,
@@ -678,9 +696,13 @@ JNIEXPORT void JNICALL SDL_JAVA_AUDIO_INTERFACE(nativeSetupJNI)(JNIEnv *env, jcl
     midAudioSetThreadPriority = (*env)->GetStaticMethodID(env, mAudioManagerClass,
                                                           "audioSetThreadPriority", "(ZI)V");
 
-    if (!midAudioOpen || !midAudioWriteByteBuffer || !midAudioWriteShortBuffer || !midAudioWriteFloatBuffer || !midAudioClose ||
-        !midCaptureOpen || !midCaptureReadByteBuffer || !midCaptureReadShortBuffer || !midCaptureReadFloatBuffer || !midCaptureClose || !midAudioSetThreadPriority) {
-        __android_log_print(ANDROID_LOG_WARN, "SDL", "Missing some Java callbacks, do you have the latest version of SDLAudioManager.java?");
+    if (!midGetAudioOutputDevices || !midGetAudioInputDevices || !midAudioOpen ||
+        !midAudioWriteByteBuffer || !midAudioWriteShortBuffer || !midAudioWriteFloatBuffer ||
+        !midAudioClose ||
+        !midCaptureOpen || !midCaptureReadByteBuffer || !midCaptureReadShortBuffer ||
+        !midCaptureReadFloatBuffer || !midCaptureClose || !midAudioSetThreadPriority) {
+        __android_log_print(ANDROID_LOG_WARN, "SDL",
+                            "Missing some Java callbacks, do you have the latest version of SDLAudioManager.java?");
     }
 
     checkJNIReady();
@@ -911,6 +933,26 @@ JNIEXPORT void JNICALL SDL_JAVA_INTERFACE(nativePermissionResult)(
     SDL_AtomicSet(&bPermissionRequestPending, SDL_FALSE);
 }
 
+extern void SDL_AddAudioDevice(const SDL_bool iscapture, const char *name, SDL_AudioSpec *spec, void *handle);
+extern void SDL_RemoveAudioDevice(const SDL_bool iscapture, void *handle);
+
+JNIEXPORT void JNICALL
+SDL_JAVA_AUDIO_INTERFACE(addAudioDevice)(JNIEnv *env, jclass jcls, jboolean is_capture,
+                                         jint device_id) {
+    int n = (int) (log10(device_id) + 1);
+    char device_name[n];
+    SDL_itoa(device_id, device_name, 10);
+    SDL_Log("Adding device with name %s, capture %d", device_name, is_capture);
+    SDL_AddAudioDevice(is_capture, SDL_strdup(device_name), NULL, (void *) ((size_t) device_id + 1));
+}
+
+JNIEXPORT void JNICALL
+SDL_JAVA_AUDIO_INTERFACE(removeAudioDevice)(JNIEnv *env, jclass jcls, jboolean is_capture,
+                                            jint device_id) {
+    SDL_Log("Removing device with handle %d, capture %d", device_id + 1, is_capture);
+    SDL_RemoveAudioDevice(is_capture, (void *) ((size_t) device_id + 1));
+}
+
 /* Paddown */
 JNIEXPORT jint JNICALL SDL_JAVA_CONTROLLER_INTERFACE(onNativePadDown)(
     JNIEnv *env, jclass jcls,
@@ -1429,7 +1471,29 @@ static void *audioBufferPinned = NULL;
 static int captureBufferFormat = 0;
 static jobject captureBuffer = NULL;
 
-int Android_JNI_OpenAudioDevice(int iscapture, SDL_AudioSpec *spec)
+void Android_JNI_GetAudioOutputDevices(int *devices, int *length) {
+    JNIEnv *env = Android_JNI_GetEnv();
+    jintArray result;
+
+    result = (*env)->CallStaticObjectMethod(env, mAudioManagerClass, midGetAudioOutputDevices);
+
+    *length = (*env)->GetArrayLength(env, result);
+
+    (*env)->GetIntArrayRegion(env, result, 0, *length, devices);
+}
+
+void Android_JNI_GetAudioInputDevices(int * devices, int *length) {
+    JNIEnv *env = Android_JNI_GetEnv();
+    jintArray result;
+
+    result = (*env)->CallStaticObjectMethod(env, mAudioManagerClass, midGetAudioInputDevices);
+
+    *length = (*env)->GetArrayLength(env, result);
+
+    (*env)->GetIntArrayRegion(env, result, 0, *length, devices);
+}
+
+int Android_JNI_OpenAudioDevice(int iscapture, int device_id, SDL_AudioSpec *spec)
 {
     int audioformat;
     jobject jbufobj = NULL;
@@ -1455,10 +1519,10 @@ int Android_JNI_OpenAudioDevice(int iscapture, SDL_AudioSpec *spec)
 
     if (iscapture) {
         __android_log_print(ANDROID_LOG_VERBOSE, "SDL", "SDL audio: opening device for capture");
-        result = (*env)->CallStaticObjectMethod(env, mAudioManagerClass, midCaptureOpen, spec->freq, audioformat, spec->channels, spec->samples);
+        result = (*env)->CallStaticObjectMethod(env, mAudioManagerClass, midCaptureOpen, spec->freq, audioformat, spec->channels, spec->samples, device_id);
     } else {
         __android_log_print(ANDROID_LOG_VERBOSE, "SDL", "SDL audio: opening device for output");
-        result = (*env)->CallStaticObjectMethod(env, mAudioManagerClass, midAudioOpen, spec->freq, audioformat, spec->channels, spec->samples);
+        result = (*env)->CallStaticObjectMethod(env, mAudioManagerClass, midAudioOpen, spec->freq, audioformat, spec->channels, spec->samples, device_id);
     }
     if (result == NULL) {
         /* Error during audio initialization, error printed from Java */

src/core/android/SDL_android.h

@@ -52,7 +52,9 @@ extern SDL_DisplayOrientation Android_JNI_GetDisplayOrientation(void);
 extern int Android_JNI_GetDisplayDPI(float *ddpi, float *xdpi, float *ydpi);
 
 /* Audio support */
-extern int Android_JNI_OpenAudioDevice(int iscapture, SDL_AudioSpec *spec);
+extern void Android_JNI_GetAudioOutputDevices(int* devices, int *length);
+extern void Android_JNI_GetAudioInputDevices(int* devices, int *length);
+extern int Android_JNI_OpenAudioDevice(int iscapture, int device_id, SDL_AudioSpec *spec);
 extern void *Android_JNI_GetAudioBuffer(void);
 extern void Android_JNI_WriteAudioBuffer(void);
 extern int Android_JNI_CaptureAudioBuffer(void *buffer, int buflen);