iOS: Initial work on interruption detection.

miniaudio.h

@@ -5781,19 +5781,19 @@ typedef struct
     {
         struct
         {
-            int __unused;
+            int _unused;
         } started;
         struct
         {
-            int __unused;
+            int _unused;
         } stopped;
         struct
         {
-            int __unused;
+            int _unused;
         } rerouted;
         struct
         {
-            int __unused;
+            int _unused;
         } interruption;
     } data;
 } ma_device_notification;
@@ -6906,7 +6906,7 @@ struct ma_device
             ma_bool32 isDefaultCaptureDevice;
             ma_bool32 isSwitchingPlaybackDevice;   /* <-- Set to true when the default device has changed and miniaudio is in the process of switching. */
             ma_bool32 isSwitchingCaptureDevice;    /* <-- Set to true when the default device has changed and miniaudio is in the process of switching. */
-            void* pRouteChangeHandler;             /* Only used on mobile platforms. Obj-C object for handling route changes. */
+            void* pNotificationHandler;             /* Only used on mobile platforms. Obj-C object for handling route changes. */
         } coreaudio;
 #endif
 #ifdef MA_SUPPORT_SNDIO
@@ -30922,7 +30922,7 @@ static ma_result ma_device_realloc_AudioBufferList__coreaudio(ma_device* pDevice
         AudioBufferList* pNewAudioBufferList;
 
         pNewAudioBufferList = ma_allocate_AudioBufferList__coreaudio(sizeInFrames, format, channels, layout, &pDevice->pContext->allocationCallbacks);
-        if (pNewAudioBufferList != NULL) {
+        if (pNewAudioBufferList == NULL) {
             return MA_OUT_OF_MEMORY;
         }
 
@@ -31053,6 +31053,9 @@ static OSStatus ma_on_input__coreaudio(void* pUserData, AudioUnitRenderActionFla
         return noErr;
     }
     
+    pRenderedBufferList = (AudioBufferList*)pDevice->coreaudio.pAudioBufferList;
+    MA_ASSERT(pRenderedBufferList);
+
     /*
     When you call AudioUnitRender(), Core Audio tries to be helpful by setting the mDataByteSize to the number of bytes
     that were actually rendered. The problem with this is that the next call can fail with -50 due to the size no longer
@@ -31424,19 +31427,23 @@ static ma_result ma_device__untrack__coreaudio(ma_device* pDevice)
 #endif
 
 #if defined(MA_APPLE_MOBILE)
-@interface ma_router_change_handler:NSObject {
+@interface ma_ios_notification_handler:NSObject {
     ma_device* m_pDevice;
 }
 @end
 
-@implementation ma_router_change_handler
+@implementation ma_ios_notification_handler
 -(id)init:(ma_device*)pDevice
 {
     self = [super init];
     m_pDevice = pDevice;
 
+    /* For route changes. */
     [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(handle_route_change:) name:AVAudioSessionRouteChangeNotification object:[AVAudioSession sharedInstance]];
 
+    /* For interruptions. */
+    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(handle_interruption:) name:AVAudioSessionInterruptionNotification object:[AVAudioSession sharedInstance]];
+
     return self;
 }
 
@@ -31448,6 +31455,26 @@ static ma_result ma_device__untrack__coreaudio(ma_device* pDevice)
 -(void)remove_handler
 {
     [[NSNotificationCenter defaultCenter] removeObserver:self name:AVAudioSessionRouteChangeNotification object:nil];
+    [[NSNotificationCenter defaultCenter] removeObserver:self name:AVAudioSessionInterruptionNotification object:nil];
+}
+
+-(void)handle_interruption:(NSNotification*)pNotification
+{
+    NSInteger type = [[[pNotification userInfo] objectForKey:AVAudioSessionInterruptionTypeKey] integerValue];
+    switch (type)
+    {
+        case AVAudioSessionInterruptionTypeBegan:
+        {
+            ma_log_postf(ma_device_get_log(m_pDevice), MA_LOG_LEVEL_DEBUG, "[Core Audio] Interruption: AVAudioSessionInterruptionTypeBegan\n");
+            ma_device__on_notification_interruption_began(m_pDevice);
+        } break;
+        
+        case AVAudioSessionInterruptionTypeEnded:
+        {
+            ma_log_postf(ma_device_get_log(m_pDevice), MA_LOG_LEVEL_DEBUG, "[Core Audio] Interruption: AVAudioSessionInterruptionTypeEnded\n");
+            ma_device__on_notification_interruption_ended(m_pDevice);
+        } break;
+    }
 }
 
 -(void)handle_route_change:(NSNotification*)pNotification
@@ -31496,29 +31523,8 @@ static ma_result ma_device__untrack__coreaudio(ma_device* pDevice)
 
     ma_log_postf(ma_device_get_log(m_pDevice), MA_LOG_LEVEL_DEBUG, "[Core Audio] Changing Route. inputNumberChannels=%d; outputNumberOfChannels=%d\n", (int)pSession.inputNumberOfChannels, (int)pSession.outputNumberOfChannels);
     
-    /* Temporarily disabling this section of code because it appears to be causing errors. */
-#if 0
-    ma_uint32 previousState = ma_device_get_state(m_pDevice);
-
-    if (previousState == ma_device_state_started) {
-        ma_device_stop(m_pDevice);
-    }
-
-    if (m_pDevice->type == ma_device_type_capture || m_pDevice->type == ma_device_type_duplex) {
-        m_pDevice->capture.internalChannels   = (ma_uint32)pSession.inputNumberOfChannels;
-        m_pDevice->capture.internalSampleRate = (ma_uint32)pSession.sampleRate;
-        ma_device__post_init_setup(m_pDevice, ma_device_type_capture);
-    }
-    if (m_pDevice->type == ma_device_type_playback || m_pDevice->type == ma_device_type_duplex) {
-        m_pDevice->playback.internalChannels   = (ma_uint32)pSession.outputNumberOfChannels;
-        m_pDevice->playback.internalSampleRate = (ma_uint32)pSession.sampleRate;
-        ma_device__post_init_setup(m_pDevice, ma_device_type_playback);
-    }
-
-    if (previousState == ma_device_state_started) {
-        ma_device_start(m_pDevice);
-    }
-#endif
+    /* Let the application know about the route change. */
+    ma_device__on_notification_rerouted(m_pDevice);
 }
 @end
 #endif
@@ -31536,9 +31542,9 @@ static ma_result ma_device_uninit__coreaudio(ma_device* pDevice)
     ma_device__untrack__coreaudio(pDevice);
 #endif
 #if defined(MA_APPLE_MOBILE)
-    if (pDevice->coreaudio.pRouteChangeHandler != NULL) {
-        ma_router_change_handler* pRouteChangeHandler = (MA_BRIDGE_TRANSFER ma_router_change_handler*)pDevice->coreaudio.pRouteChangeHandler;
-        [pRouteChangeHandler remove_handler];
+    if (pDevice->coreaudio.pNotificationHandler != NULL) {
+        ma_ios_notification_handler* pNotificationHandler = (MA_BRIDGE_TRANSFER ma_ios_notification_handler*)pDevice->coreaudio.pNotificationHandler;
+        [pNotificationHandler remove_handler];
     }
 #endif
 
@@ -32212,7 +32218,7 @@ static ma_result ma_device_init__coreaudio(ma_device* pDevice, const ma_device_c
     differently on non-Desktop Apple platforms.
     */
 #if defined(MA_APPLE_MOBILE)
-    pDevice->coreaudio.pRouteChangeHandler = (MA_BRIDGE_RETAINED void*)[[ma_router_change_handler alloc] init:pDevice];
+    pDevice->coreaudio.pNotificationHandler = (MA_BRIDGE_RETAINED void*)[[ma_ios_notification_handler alloc] init:pDevice];
 #endif
 
     return MA_SUCCESS;