Fix Bug 1019 - Remedy of Bug 691 causes 'access/modify after free' and crashes the app

The 'magic' MyNSOpenGLContext::dealloc (MacOSXWindowSystemInterface-calayer.m)
of force destroying the underlying CGLContextObj of it's associated
NSOpenGLContext as introduced as a remedy of Bug 691 is plain wrong.

It was added in commit f6e6fab2a7ddfb5c9b614cb072c27ff697629161
to mitigate the experience behavior of delayed GL context
destruction when creating/destroying them multiple times
as exposed in unit test TestGLCanvasAddRemove01SwingAWT.

While this 'hack' worked for some reason on some OSX versions,
it caused a 'access/modify after free' issue exposed under some circumstances
and crashes the application.

The actual culprit of the delayed GL context destruction is different.
The offthread CALayer detachment and hence final destruction
issued on the main-thread is _not_ issued immediately
due to some referencing holding by NSApp.
Issuing an empty event on the NSApp (thread) will wake up the thread
and release claimed resources.

This has been found while realizing that the GL context
are released if the mouse is being moved (duh!).
This issue is also known when triggering stop on the NSApp (NEWT MainThread),
same remedy has been implemented here for a long time.

2 files changed, 89 insertions, 67 deletions

diff --git a/src/nativewindow/classes/jogamp/nativewindow/jawt/macosx/MacOSXJAWTWindow.java b/src/nativewindow/classes/jogamp/nativewindow/jawt/macosx/MacOSXJAWTWindow.java
index 3728bfb59..e64525fbe 100644
--- a/src/nativewindow/classes/jogamp/nativewindow/jawt/macosx/MacOSXJAWTWindow.java
+++ b/src/nativewindow/classes/jogamp/nativewindow/jawt/macosx/MacOSXJAWTWindow.java
@@ -96,7 +96,7 @@ public class MacOSXJAWTWindow extends JAWTWindow implements MutableSurface {
           if(0 != windowHandle) {
               OSXUtil.DestroyNSWindow(windowHandle);
           }
-          OSXUtil.RunOnMainThread(false, new Runnable() {
+          OSXUtil.RunOnMainThread(false, true /* kickNSApp */, new Runnable() {
               @Override
               public void run() {
                   if( 0 != rootSurfaceLayer ) {
@@ -121,7 +121,7 @@ public class MacOSXJAWTWindow extends JAWTWindow implements MutableSurface {
           updatePixelScale();
 
           if( hadPixelScaleX != getPixelScaleX() && 0 != getAttachedSurfaceLayer() ) {
-              OSXUtil.RunOnMainThread(false, new Runnable() {
+              OSXUtil.RunOnMainThread(false, false, new Runnable() {
                   @Override
                   public void run() {
                       final long osl = getAttachedSurfaceLayer();
@@ -136,37 +136,37 @@ public class MacOSXJAWTWindow extends JAWTWindow implements MutableSurface {
 
   @Override
   protected void attachSurfaceLayerImpl(final long layerHandle) {
-      OSXUtil.RunOnMainThread(false, new Runnable() {
-          @Override
-          public void run() {
-              // AWT position is top-left w/ insets, where CALayer position is bottom/left from root CALayer w/o insets.
-              // Determine p0: components location on screen w/o insets.
-              // CALayer position will be determined in native code.
-              // See detailed description in {@link JAWTUtil#JAWT_OSX_CALAYER_QUIRK_LAYOUT}
-              final Point p0 = new Point();
-              final Component outterComp = getLocationOnScreenNonBlocking(p0, component);
-              final java.awt.Insets outterInsets = AWTMisc.getInsets(outterComp, true);
-              final Point p1 = (Point)p0.cloneMutable();
-              p1.translate(-outterComp.getX(), -outterComp.getY());
-              if( null != outterInsets ) {
-                  p1.translate(-outterInsets.left, -outterInsets.top);
-              }
-
-              if( DEBUG_CALAYER_POS_CRITICAL ) {
-                  final java.awt.Point pA0 = component.getLocationOnScreen();
-                  final Point pA1 = new Point(pA0.x, pA0.y);
-                  pA1.translate(-outterComp.getX(), -outterComp.getY());
+      OSXUtil.RunOnMainThread(false, false /* kickNSApp */, new Runnable() {
+              @Override
+              public void run() {
+                  // AWT position is top-left w/ insets, where CALayer position is bottom/left from root CALayer w/o insets.
+                  // Determine p0: components location on screen w/o insets.
+                  // CALayer position will be determined in native code.
+                  // See detailed description in {@link JAWTUtil#JAWT_OSX_CALAYER_QUIRK_LAYOUT}
+                  final Point p0 = new Point();
+                  final Component outterComp = getLocationOnScreenNonBlocking(p0, component);
+                  final java.awt.Insets outterInsets = AWTMisc.getInsets(outterComp, true);
+                  final Point p1 = (Point)p0.cloneMutable();
+                  p1.translate(-outterComp.getX(), -outterComp.getY());
                   if( null != outterInsets ) {
-                      pA1.translate(-outterInsets.left, -outterInsets.top);
+                      p1.translate(-outterInsets.left, -outterInsets.top);
                   }
-                  System.err.println("JAWTWindow.attachSurfaceLayerImpl: "+toHexString(layerHandle) + ", [ins "+outterInsets+"], pA "+pA0+" -> "+pA1+
-                          ", p0 "+p0+" -> "+p1+", bounds "+bounds);
-              } else if( DEBUG ) {
-                  System.err.println("JAWTWindow.attachSurfaceLayerImpl: "+toHexString(layerHandle) + ", [ins "+outterInsets+"], p0 "+p0+" -> "+p1+", bounds "+bounds);
-              }
-              // HiDPI: uniform pixel scale
-              OSXUtil.AddCASublayer(rootSurfaceLayer, layerHandle, p1.getX(), p1.getY(), getWidth(), getHeight(), getPixelScaleX(), JAWTUtil.getOSXCALayerQuirks());
-          } } );
+
+                  if( DEBUG_CALAYER_POS_CRITICAL ) {
+                      final java.awt.Point pA0 = component.getLocationOnScreen();
+                      final Point pA1 = new Point(pA0.x, pA0.y);
+                      pA1.translate(-outterComp.getX(), -outterComp.getY());
+                      if( null != outterInsets ) {
+                          pA1.translate(-outterInsets.left, -outterInsets.top);
+                      }
+                      System.err.println("JAWTWindow.attachSurfaceLayerImpl: "+toHexString(layerHandle) + ", [ins "+outterInsets+"], pA "+pA0+" -> "+pA1+
+                              ", p0 "+p0+" -> "+p1+", bounds "+bounds);
+                  } else if( DEBUG ) {
+                      System.err.println("JAWTWindow.attachSurfaceLayerImpl: "+toHexString(layerHandle) + ", [ins "+outterInsets+"], p0 "+p0+" -> "+p1+", bounds "+bounds);
+                  }
+                  // HiDPI: uniform pixel scale
+                  OSXUtil.AddCASublayer(rootSurfaceLayer, layerHandle, p1.getX(), p1.getY(), getWidth(), getHeight(), getPixelScaleX(), JAWTUtil.getOSXCALayerQuirks());
+              } } );
   }
 
   @Override
@@ -204,12 +204,12 @@ public class MacOSXJAWTWindow extends JAWTWindow implements MutableSurface {
 
   @Override
   protected void detachSurfaceLayerImpl(final long layerHandle, final Runnable detachNotify) {
-      OSXUtil.RunOnMainThread(false, new Runnable() {
-          @Override
-          public void run() {
-              detachNotify.run();
-              OSXUtil.RemoveCASublayer(rootSurfaceLayer, layerHandle);
-          } } );
+      OSXUtil.RunOnMainThread(false, true /* kickNSApp */, new Runnable() {
+              @Override
+              public void run() {
+                  detachNotify.run();
+                  OSXUtil.RemoveCASublayer(rootSurfaceLayer, layerHandle);
+              } });
   }
 
   @Override
@@ -326,30 +326,30 @@ public class MacOSXJAWTWindow extends JAWTWindow implements MutableSurface {
         }
         if(null == errMsg) {
             jawtSurfaceLayersHandle = GetJAWTSurfaceLayersHandle0(dsi.getBuffer());
-            OSXUtil.RunOnMainThread(false, new Runnable() {
-                @Override
-                public void run() {
-                    String errMsg = null;
-                    if(0 == rootSurfaceLayer && 0 != jawtSurfaceLayersHandle) {
-                        rootSurfaceLayer = OSXUtil.CreateCALayer(bounds.getWidth(), bounds.getHeight(), getPixelScaleX()); // HiDPI: uniform pixel scale
-                        if(0 == rootSurfaceLayer) {
-                          errMsg = "Could not create root CALayer";
-                        } else {
-                            try {
-                                SetJAWTRootSurfaceLayer0(jawtSurfaceLayersHandle, rootSurfaceLayer);
-                            } catch(Exception e) {
-                                errMsg = "Could not set JAWT rootSurfaceLayerHandle "+toHexString(rootSurfaceLayer)+", cause: "+e.getMessage();
+            OSXUtil.RunOnMainThread(false, false, new Runnable() {
+                    @Override
+                    public void run() {
+                        String errMsg = null;
+                        if(0 == rootSurfaceLayer && 0 != jawtSurfaceLayersHandle) {
+                            rootSurfaceLayer = OSXUtil.CreateCALayer(bounds.getWidth(), bounds.getHeight(), getPixelScaleX()); // HiDPI: uniform pixel scale
+                            if(0 == rootSurfaceLayer) {
+                              errMsg = "Could not create root CALayer";
+                            } else {
+                                try {
+                                    SetJAWTRootSurfaceLayer0(jawtSurfaceLayersHandle, rootSurfaceLayer);
+                                } catch(Exception e) {
+                                    errMsg = "Could not set JAWT rootSurfaceLayerHandle "+toHexString(rootSurfaceLayer)+", cause: "+e.getMessage();
+                                }
                             }
-                        }
-                        if(null != errMsg) {
-                            if(0 != rootSurfaceLayer) {
-                              OSXUtil.DestroyCALayer(rootSurfaceLayer);
-                              rootSurfaceLayer = 0;
+                            if(null != errMsg) {
+                                if(0 != rootSurfaceLayer) {
+                                  OSXUtil.DestroyCALayer(rootSurfaceLayer);
+                                  rootSurfaceLayer = 0;
+                                }
+                                throw new NativeWindowException(errMsg+": "+MacOSXJAWTWindow.this);
                             }
-                            throw new NativeWindowException(errMsg+": "+MacOSXJAWTWindow.this);
                         }
-                    }
-                } } );
+                    } } );
         }
         if(null != errMsg) {
             if(0 != windowHandle) {
diff --git a/src/nativewindow/classes/jogamp/nativewindow/macosx/OSXUtil.java b/src/nativewindow/classes/jogamp/nativewindow/macosx/OSXUtil.java
index a91698f62..22ac9c355 100644
--- a/src/nativewindow/classes/jogamp/nativewindow/macosx/OSXUtil.java
+++ b/src/nativewindow/classes/jogamp/nativewindow/macosx/OSXUtil.java
@@ -251,9 +251,10 @@ public class OSXUtil implements ToolkitProperties {
      * </p>
      *
      * @param waitUntilDone
+     * @param kickNSApp if <code>true</code> issues {@link #KickNSApp()}
      * @param runnable
      */
-    public static void RunOnMainThread(boolean waitUntilDone, Runnable runnable) {
+    public static void RunOnMainThread(final boolean waitUntilDone, final boolean kickNSApp, final Runnable runnable) {
         if( IsMainThread0() ) {
             runnable.run(); // don't leave the JVM
         } else {
@@ -263,7 +264,7 @@ public class OSXUtil implements ToolkitProperties {
             final Object sync = new Object();
             final RunnableTask rt = new RunnableTask( runnable, waitUntilDone ? sync : null, true, waitUntilDone ? null : System.err );
             synchronized(sync) {
-                RunOnMainThread0(rt);
+                RunOnMainThread0(kickNSApp, rt);
                 if( waitUntilDone ) {
                     try {
                         sync.wait();
@@ -288,14 +289,33 @@ public class OSXUtil implements ToolkitProperties {
      * @param delay delay to run the runnable in milliseconds
      */
     public static void RunLater(boolean onMain, Runnable runnable, int delay) {
-        RunLater0(onMain, new RunnableTask( runnable, null, true, System.err ), delay);
+        RunLater0(onMain, false /* kickNSApp */, new RunnableTask( runnable, null, true, System.err ), delay);
+    }
+
+    /**
+     * Wakes up NSApp thread by sending an empty NSEvent ..
+     * <p>
+     * This is deemed important <i>sometimes</i> where resources shall get freed ASAP, e.g. GL context etc.
+     * </p>
+     * <p>
+     * The following scenarios requiring this <i>wake-up</i> are currently known:
+     * <ul>
+     *   <li>Destruction of an OpenGL context</li>
+     *   <li>Destruction of Windows .. ?</li>
+     *   <li>Stopping the NSApp</li>
+     * </ul>
+     * </p>
+     * FIXME: Complete list of scenarios and reason it.
+     */
+    public static void KickNSApp() {
+        KickNSApp0();
     }
 
     private static Runnable _nop = new Runnable() { @Override public void run() {}; };
 
-    /** Issues a {@link #RunOnMainThread(boolean, Runnable)} w/ an <i>NOP</i> runnable, while waiting until done. */
+    /** Issues a {@link #RunOnMainThread(boolean, boolean, Runnable)} w/ an <i>NOP</i> runnable, while waiting until done and issuing {@link #KickNSApp()}. */
     public static void WaitUntilFinish() {
-        RunOnMainThread(true, _nop);
+        RunOnMainThread(true, true /* kickNSApp */, _nop);
     }
 
     /**
@@ -305,9 +325,10 @@ public class OSXUtil implements ToolkitProperties {
      * </p>
      *
      * @param waitUntilDone
+     * @param kickNSApp if <code>true</code> issues {@link #KickNSApp()}
      * @param func
      */
-    public static <R,A> R RunOnMainThread(boolean waitUntilDone, Function<R,A> func, A... args) {
+    public static <R,A> R RunOnMainThread(final boolean waitUntilDone, final boolean kickNSApp, final Function<R,A> func, final A... args) {
         if( IsMainThread0() ) {
             return func.eval(args); // don't leave the JVM
         } else {
@@ -318,7 +339,7 @@ public class OSXUtil implements ToolkitProperties {
             final FunctionTask<R,A> rt = new FunctionTask<R,A>( func, waitUntilDone ? sync : null, true, waitUntilDone ? null : System.err );
             synchronized(sync) {
                 rt.setArgs(args);
-                RunOnMainThread0(rt);
+                RunOnMainThread0(kickNSApp, rt);
                 if( waitUntilDone ) {
                     try {
                         sync.wait();
@@ -384,8 +405,9 @@ public class OSXUtil implements ToolkitProperties {
     private static native void SetCALayerPixelScale0(long rootCALayer, long subCALayer, float contentsScale);
     private static native void RemoveCASublayer0(long rootCALayer, long subCALayer);
     private static native void DestroyCALayer0(long caLayer);
-    private static native void RunOnMainThread0(Runnable runnable);
-    private static native void RunLater0(boolean onMain, Runnable runnable, int delay);
+    private static native void RunOnMainThread0(boolean kickNSApp, Runnable runnable);
+    private static native void RunLater0(boolean onMain, boolean kickNSApp, Runnable runnable, int delay);
+    private static native void KickNSApp0();
     private static native boolean IsMainThread0();
     private static native int GetScreenRefreshRate0(int scrn_idx);
 }