darwin: Pause the audio when sleeping

Updates hajimehoshi/ebiten#1259

driver_darwin.go

@@ -21,6 +21,8 @@ package oto
 // #import <AudioToolbox/AudioToolbox.h>
 //
 // void oto_render(void* inUserData, AudioQueueRef inAQ, AudioQueueBufferRef inBuffer);
+//
+// void oto_setNotificationHandler(AudioQueueRef audioQueue);
 import "C"
 
 import (
@@ -242,3 +244,17 @@ func (d *driver) Close() error {
 	setDriver(nil)
 	return nil
 }
+
+func setNotificationHandler(driver *driver) {
+	C.oto_setNotificationHandler(driver.audioQueue)
+}
+
+//export oto_setErrorByNotification
+func oto_setErrorByNotification(s C.OSStatus, from *C.char) {
+	if theDriver.err != nil {
+		return
+	}
+
+	gofrom := C.GoString(from)
+	theDriver.err = fmt.Errorf("oto: %s at notification failed: %d", gofrom, s)
+}

driver_ios.go

@@ -20,28 +20,12 @@ package oto
 // #cgo LDFLAGS: -framework Foundation -framework AVFoundation
 //
 // #import <AudioToolbox/AudioToolbox.h>
-//
-// void oto_setNotificationHandler(AudioQueueRef audioQueue);
 import "C"
 
 import (
 	"fmt"
 )
 
-func setNotificationHandler(driver *driver) {
-	C.oto_setNotificationHandler(driver.audioQueue)
-}
-
 func componentSubType() C.OSType {
 	return C.kAudioUnitSubType_RemoteIO
 }
-
-//export oto_setErrorByNotification
-func oto_setErrorByNotification(s C.OSStatus, from *C.char) {
-	if theDriver.err != nil {
-		return
-	}
-
-	gofrom := C.GoString(from)
-	theDriver.err = fmt.Errorf("oto: %s at notification failed: %d", gofrom, s)
-}

driver_macos.go

@@ -17,13 +17,11 @@
 
 package oto
 
+// #cgo LDFLAGS: -framework AppKit
+//
 // #import <AudioToolbox/AudioToolbox.h>
 import "C"
 
-func setNotificationHandler(driver *driver) {
-	// Do nothing
-}
-
 func componentSubType() C.OSType {
 	return C.kAudioUnitSubType_DefaultOutput
 }

driver_macos.m

@@ -0,0 +1,63 @@
+// Copyright 2020 The Oto Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build darwin,!ios,!js
+
+#import <AppKit/AppKit.h>
+
+#include "_cgo_export.h"
+
+@interface OtoInterruptObserver : NSObject {
+}
+
+@property(nonatomic) AudioQueueRef audioQueue;
+
+@end
+
+@implementation OtoInterruptObserver {
+  AudioQueueRef _audioQueue;
+}
+
+- (void)receiveSleepNote:(NSNotification *)note {
+  OSStatus status = AudioQueuePause([self audioQueue]);
+  if (status != noErr) {
+    oto_setErrorByNotification(status, "AudioQueuePause");
+  }
+}
+
+- (void)receiveWakeNote:(NSNotification *)note {
+  OSStatus status = AudioQueueStart([self audioQueue], nil);
+  if (status != noErr) {
+    oto_setErrorByNotification(status, "AudioQueueStart");
+  }
+}
+
+@end
+
+// oto_setNotificationHandler sets a handler for interruption events.
+void oto_setNotificationHandler(AudioQueueRef audioQueue) {
+  OtoInterruptObserver *observer = [[OtoInterruptObserver alloc] init];
+  observer.audioQueue = audioQueue;
+
+  [[[NSWorkspace sharedWorkspace] notificationCenter]
+      addObserver:observer
+         selector:@selector(receiveSleepNote:)
+             name:NSWorkspaceWillSleepNotification
+           object:NULL];
+  [[[NSWorkspace sharedWorkspace] notificationCenter]
+      addObserver:observer
+         selector:@selector(receiveWakeNote:)
+             name:NSWorkspaceDidWakeNotification
+           object:NULL];
+}