Workaround (Fix) for Bug 502: Multithreading issue w/ libX11 1.4.2 and libxcb 1.7 bug 20708

See https://jogamp.org/bugzilla/show_bug.cgi?id=502

Since the libX11/xcb code doesn't seem to be fixed anytime soon
a better usable workaround is required than using a system property
to enable 'over locking'.

It turns out that the race condition is related to the parallel
X11 Display connection usage of GLX/OpenGL and event dispatching.
This workaround utilizes 2 X11 Display handles, one for windowing/OpenGL
and one for event dispatching.
This approach allows us to cont. multithreading use w/o locking the display
and works on both implementations, the old bug-free libX11 and the 'new' buggy one.

Downside is the little resource overhead of the 2nd X11 Display connection .. well.

- Removes the property: 'nativewindow.x11.mt-bug'

2 files changed, 40 insertions, 13 deletions

diff --git a/src/newt/classes/jogamp/newt/driver/x11/X11Display.java b/src/newt/classes/jogamp/newt/driver/x11/X11Display.java
index 483556f82..94e5a0bcc 100644
--- a/src/newt/classes/jogamp/newt/driver/x11/X11Display.java
+++ b/src/newt/classes/jogamp/newt/driver/x11/X11Display.java
@@ -69,14 +69,23 @@ public class X11Display extends DisplayImpl {
         if( 0 == handle ) {
             throw new RuntimeException("Error creating display: "+name);
         }
+        if(USE_SEPARATE_DISPLAY_FOR_EDT) {
+            edtDisplayHandle = X11Util.createDisplay(name);
+            if( 0 == edtDisplayHandle ) {
+                X11Util.closeDisplay(handle);
+                throw new RuntimeException("Error creating display(EDT): "+name);
+            }
+        } else {
+            edtDisplayHandle = handle;
+        }
         try {
-            CompleteDisplay0(handle);
+            CompleteDisplay0(edtDisplayHandle);
         } catch(RuntimeException e) {
-            X11Util.closeDisplay(handle);
+            closeNativeImpl();
             throw e;
         }
         
-        if(X11Util.XINITTHREADS_ALWAYS_ENABLED && !X11Util.MULTITHREADING_BUG) {
+        if(X11Util.XINITTHREADS_ALWAYS_ENABLED) {
             // Hack: Force non X11Display locking, even w/ AWT and w/o isFirstUIActionOnProcess() 
             aDevice = new X11GraphicsDevice(handle, AbstractGraphicsDevice.DEFAULT_UNIT, NativeWindowFactory.getNullToolkitLock());            
         } else {
@@ -86,25 +95,29 @@ public class X11Display extends DisplayImpl {
     }
 
     protected void closeNativeImpl() {
-        X11Util.closeDisplay(getHandle());
+        final long handle = getHandle();
+        if(handle != edtDisplayHandle) {
+            X11Util.closeDisplay(edtDisplayHandle);
+        }
+        X11Util.closeDisplay(handle);
     }
 
     protected void dispatchMessagesNative() {
-        long dpy = getHandle();
-        if(0!=dpy) {
-            DispatchMessages0(dpy, javaObjectAtom, windowDeleteAtom);
+        if(0 != edtDisplayHandle) {
+            DispatchMessages0(edtDisplayHandle, javaObjectAtom, windowDeleteAtom);
         }
     }
 
+    protected long getEDTHandle() { return edtDisplayHandle; }
     protected long getJavaObjectAtom() { return javaObjectAtom; }
     protected long getWindowDeleteAtom() { return windowDeleteAtom; }
-
+    
     //----------------------------------------------------------------------
     // Internals only
     //
     private static native boolean initIDs0();
 
-    private native void CompleteDisplay0(long handle);
+    private native void CompleteDisplay0(long handleEDT);
 
     private native void DispatchMessages0(long display, long javaObjectAtom, long windowDeleteAtom);
 
@@ -113,7 +126,21 @@ public class X11Display extends DisplayImpl {
         this.windowDeleteAtom=windowDeleteAtom;
     }
 
+    /**
+     * 2011/06/14 libX11 1.4.2 and libxcb 1.7 bug 20708 - Multithreading Issues w/ OpenGL, ..
+     *            https://bugs.freedesktop.org/show_bug.cgi?id=20708
+     *            https://jogamp.org/bugzilla/show_bug.cgi?id=502
+     *            Affects: Ubuntu 11.04, OpenSuSE 11, ..
+     *            Workaround: Using a separate X11 Display connection for event dispatching (EDT)
+     */    
+    private final boolean USE_SEPARATE_DISPLAY_FOR_EDT = true;
+    
+    private long edtDisplayHandle;
+    
+    /** X11 Window delete atom marker used on EDT */
     private long windowDeleteAtom;
+    
+    /** X11 Window java object property used on EDT */
     private long javaObjectAtom;
 }
 
diff --git a/src/newt/classes/jogamp/newt/driver/x11/X11Window.java b/src/newt/classes/jogamp/newt/driver/x11/X11Window.java
index 19a0c7626..cbb43934b 100644
--- a/src/newt/classes/jogamp/newt/driver/x11/X11Window.java
+++ b/src/newt/classes/jogamp/newt/driver/x11/X11Window.java
@@ -64,7 +64,7 @@ public class X11Window extends WindowImpl {
         X11GraphicsConfiguration x11config = (X11GraphicsConfiguration) config;
         long visualID = x11config.getVisualID();
         long w = CreateWindow0(getParentWindowHandle(),
-                               display.getHandle(), screen.getIndex(), visualID, 
+                               display.getHandle(), display.getEDTHandle(), screen.getIndex(), visualID, 
                                display.getJavaObjectAtom(), display.getWindowDeleteAtom(), 
                                x, y, width, height, isUndecorated());
         if (w == 0) {
@@ -78,7 +78,7 @@ public class X11Window extends WindowImpl {
         if(0!=windowHandleClose && null!=getScreen() ) {
             X11Display display = (X11Display) getScreen().getDisplay();
             try {
-                CloseWindow0(display.getHandle(), windowHandleClose, 
+                CloseWindow0(display.getHandle(), display.getEDTHandle(), windowHandleClose, 
                              display.getJavaObjectAtom(), display.getWindowDeleteAtom());
             } catch (Throwable t) {
                 if(DEBUG_IMPLEMENTATION) { 
@@ -124,10 +124,10 @@ public class X11Window extends WindowImpl {
     //
 
     protected static native boolean initIDs0();
-    private native long CreateWindow0(long parentWindowHandle, long display, int screen_index, 
+    private native long CreateWindow0(long parentWindowHandle, long display, long displayEDT, int screen_index, 
                                             long visualID, long javaObjectAtom, long windowDeleteAtom, 
                                             int x, int y, int width, int height, boolean undecorated);
-    private native void CloseWindow0(long display, long windowHandle, long javaObjectAtom, long windowDeleteAtom);
+    private native void CloseWindow0(long display, long displayEDT, long windowHandle, long javaObjectAtom, long windowDeleteAtom);
     private native void setVisible0(long display, long windowHandle, boolean visible, int x, int y, int width, int height);
     private native void reconfigureWindow0(long display, int screen_index, long parentWindowHandle, long windowHandle, 
                                                   int x, int y, int width, int height, boolean isVisible,