kc3-lang/SDL

2017-07-10T17:07:19

Fixed bug 3697 - Main thread gets stuck on left mouse down Amruth Raj - My app runs in full screen to play video(I use SDL_WINDOW_FULLSCREEN_DESKTOP) - Cmd-tab to go out of full screen to another app - Cmd-tab again to get back to my app - Press left mouse button at one of the edges of the screen, don't release yet. After this point the main thread is stuck until I release the left mouse button and hence video rendering doesn't happen anymore. On debugging more, I see that thread 0 is stuck as shown below with sendEvent processing left mouse down. It comes out only after it receives a left mouse up. There are some frames below which show NSWindowResizing, but my window flag doesn't have SDL_WINDOW_RESIZABLE set. Thread 0:: CrBrowserMain Dispatch queue: com.apple.main-thread 0 libsystem_kernel.dylib 0x00007fffbe13d34a mach_msg_trap + 10 1 libsystem_kernel.dylib 0x00007fffbe13c797 mach_msg + 55 2 com.apple.CoreFoundation 0x00007fffa889d434 __CFRunLoopServiceMachPort + 212 3 com.apple.CoreFoundation 0x00007fffa889c8c1 __CFRunLoopRun + 1361 4 com.apple.CoreFoundation 0x00007fffa889c114 CFRunLoopRunSpecific + 420 5 com.apple.HIToolbox 0x00007fffa7dfdebc RunCurrentEventLoopInMode + 240 6 com.apple.HIToolbox 0x00007fffa7dfdcf1 ReceiveNextEventCommon + 432 7 com.apple.HIToolbox 0x00007fffa7dfdb26 _BlockUntilNextEventMatchingListInModeWithFilter + 71 8 com.apple.AppKit 0x00007fffa6396a54 _DPSNextEvent + 1120 9 com.apple.AppKit 0x00007fffa6b127ee -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 2796 10 com.apple.AppKit 0x00007fffa66f568d +[NSWindow(NSWindowResizing) _mouseHysteresisCheck:withExpiration:andDistance:finalMouseLocation:] + 525 11 com.apple.AppKit 0x00007fffa65eedb5 -[NSWindow(NSWindowResizing) _hitTestWithHysteresisCheck:forEvent:allowWindowDragging:] + 394 12 com.apple.AppKit 0x00007fffa6c8f0db -[NSWindow(NSEventRouting) _handleMouseDownEvent:isDelayedEvent:] + 1873 13 com.apple.AppKit 0x00007fffa6c8ca6c -[NSWindow(NSEventRouting) _reallySendEvent:isDelayedEvent:] + 1942 14 com.apple.AppKit 0x00007fffa6c8bf0a -[NSWindow(NSEventRouting) sendEvent:] + 541 15 org.libsdl.SDL2 0x000000010d46d74a -[SDLWindow sendEvent:] + 90 16 com.apple.AppKit 0x00007fffa6b10681 -[NSApplication(NSEvent) sendEvent:] + 1145 17 org.libsdl.SDL2 0x000000010d46532b -[SDLApplication sendEvent:] + 139 18 org.libsdl.SDL2 0x000000010d466b2f Cocoa_PumpEvents + 495 19 org.libsdl.SDL2 0x000000010d44c1d5 SDL_PumpEvents_REAL + 53 20 org.libsdl.SDL2 0x000000010d44c2f5 SDL_WaitEventTimeout_REAL + 53 21 org.libsdl.SDL2 0x000000010d44c2b7 SDL_PollEvent_REAL + 23 22 org.libsdl.SDL2 0x000000010d51bb24 SDL_PollEvent + 36 23 libTest.dylib 0x000000010cf3e0e8 SDLEventProcessor::processEvents(int) + 568 24 Test 0x000000010cde6bba BrowserApp::RunAppMessageLoop(BAInstData*, CefStringBase, CefStringBase) + 810 25 Test 0x000000010ce04bbc main + 17980 26 libdyld.dylib 0x00007fffbe016235 start + 1 I further noticed that while entering full screen in SDL_cocoawindow.m NSResizableWindowMask is set. If I clear it inside windowDidEnterFullScreen, then, the issue doesn't repro. This is discussed at https://discourse.libsdl.org/t/main-thread-gets-stuck-on-left-mouse-down/22753/3 and thanks to Eric for the pointers.

diff --git a/src/video/cocoa/SDL_cocoawindow.m b/src/video/cocoa/SDL_cocoawindow.m
index 6d61867..ac605fc 100644
--- a/src/video/cocoa/SDL_cocoawindow.m
+++ b/src/video/cocoa/SDL_cocoawindow.m
@@ -674,6 +674,7 @@ SetWindowStyle(SDL_Window * window, NSUInteger style)
         pendingWindowOperation = PENDING_OPERATION_NONE;
         [self setFullscreenSpace:NO];
     } else {
+        SetWindowStyle(window, 0);
         if ((window->flags & SDL_WINDOW_FULLSCREEN_DESKTOP) == SDL_WINDOW_FULLSCREEN_DESKTOP) {
             [NSMenu setMenuBarVisible:NO];
         }