Workaround deadlocks when starting IO on macOS Big Sur.

This works similarly to the workaround in the previous commit, but avoids the short wait while XPC times out. It still allows some initial frames to be dropped when IO starts. See #328, #388 and PR #390.
kyleneideck · Nov 25, 2020 · c0ab98b · c0ab98b
1 parent 043bfb3
commit c0ab98b
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Showing 3 changed files with 13 additions and 5 deletions.
diff --git a/BGMApp/BGMApp/BGMAudioDeviceManager.mm b/BGMApp/BGMApp/BGMAudioDeviceManager.mm
@@ -378,8 +378,14 @@ - (OSStatus) startPlayThroughSync:(BOOL)forUISoundsDevice {
 
     @try {
         gotLock = [stateLock tryLock];
-
-        if (gotLock) {
+
+        BOOL isBigSur = NO;
+        if (@available(macOS 11.0, *)) {
+            isBigSur = YES;
+        }
+
+        // Always start playthrough asynchronously. Temp workaround for deadlock on Big Sur.
+        if (!isBigSur && gotLock) {
             BGMPlayThrough& pt = (forUISoundsDevice ? playThrough_UISounds : playThrough);
 
             // Playthrough might not have been notified that BGMDevice is starting yet, so make sure

diff --git a/BGMDriver/BGMDriver/BGM_Device.cpp b/BGMDriver/BGMDriver/BGM_Device.cpp
@@ -20,6 +20,7 @@
 //  Copyright © 2016, 2017, 2019 Kyle Neideck
 //  Copyright © 2017 Andrew Tonner
 //  Copyright © 2019 Gordon Childs
+//  Copyright © 2020 Aleksey Yurkevich
 //  Copyright (C) 2013 Apple Inc. All Rights Reserved.
 //
 //  Based largely on SA_Device.cpp from Apple's SimpleAudioDriver Plug-In sample code. Also uses a few sections from Apple's

diff --git a/BGMDriver/BGMDriver/BGM_XPCHelper.m b/BGMDriver/BGMDriver/BGM_XPCHelper.m
@@ -14,10 +14,11 @@
 // along with Background Music. If not, see <http://www.gnu.org/licenses/>.
 
 //
-//  BGM_XPCHelper.cpp
+//  BGM_XPCHelper.m
 //  BGMDriver
 //
-//  Copyright © 2016, 2017 Kyle Neideck
+//  Copyright © 2016, 2017, 2020 Kyle Neideck
+//  Copyright © 2020 Aleksey Yurkevich
 //
 
 // Self Include
@@ -35,7 +36,7 @@
 
 #pragma clang assume_nonnull begin
 
-static const UInt64 REMOTE_CALL_DEFAULT_TIMEOUT_SECS = 1;
+static const UInt64 REMOTE_CALL_DEFAULT_TIMEOUT_SECS = 30;
 
 static NSXPCConnection* CreateXPCHelperConnection()
 {