- Fix: Native X11 Display deadlock (Linux x86_64 32bit on 64bit)

    It turns out that under some circumstances,
    e.g. >3 threads within initialization time,
    the static X11Display usage result in a 
    native deadlock within glXQueryServerString().
    The call never returned. May be 
    This happend even with NativeWindowFactory.getDefaultFactory().getToolkitLock().lock();

    Removed X11Util.getStaticDefaultDisplay()

    This allows us to remove the ToolkitLock around
    these segments, due to a thread local X11Display utilization.




git-svn-id: file:///usr/local/projects/SUN/JOGL/git-svn/svn-server-sync/jogl/trunk@1977 232f8b59-042b-4e1e-8c03-345bb8c30851

3 files changed, 11 insertions, 62 deletions

diff --git a/src/nativewindow/classes/com/sun/nativewindow/impl/x11/X11Util.java b/src/nativewindow/classes/com/sun/nativewindow/impl/x11/X11Util.java
index 38d0fb73d..acd55a823 100644
--- a/src/nativewindow/classes/com/sun/nativewindow/impl/x11/X11Util.java
+++ b/src/nativewindow/classes/com/sun/nativewindow/impl/x11/X11Util.java
@@ -39,28 +39,11 @@ import javax.media.nativewindow.*;
 import com.sun.nativewindow.impl.*;
 
 /**
- * Contains a thread safe X11 utility to retrieve tread local display connection,<br>
+ * Contains a thread safe X11 utility to retrieve thread local display connection,<br>
  * as well as the static global discplay connection.<br>
  *
- * The TLS variant is thread safe per se, but has the memory leak risk on applications
- * heavily utilizing runnables on a new thread.<br>
- * 
- * The static variant is more nice to resources, but involves the default toolkit
- * locking mechanism, which invocation you have to provide as shown below.<br>
- * <PRE>
-   NativeWindowFactory.getDefaultFactory().getToolkitLock().lock();
-   try {
-     long displayHandle = X11Util.getStaticDefaultDisplay();
-     ...
-   } finally {
-     NativeWindowFactory.getDefaultFactory().getToolkitLock().unlock();
-   }
- * </PRE><br>
- *
- * We will use the TLS variant, where a long term display connection is being used,
- * ie in JOGL's <code>X11AWTGLXGraphicsConfigurationFactory</code>,
- * on all other situations where we just query some X11 attributes,
- * the locked static variant shall be used instead.<br>
+ * The TLS variant is thread safe per se, but be aware of the memory leak risk 
+ * where an application heavily utilizing this class on temporary new threads.<br>
  */
 public class X11Util {
     private static final boolean DEBUG = Debug.debug("X11Util");
@@ -73,43 +56,13 @@ public class X11Util {
 
     private static ThreadLocal currentDisplayAssociation = new ThreadLocal();
 
-    private static volatile long    staticDefaultDisplay=0; 
-    private static boolean staticDefaultDisplayXineramaEnable=false; 
-
-    private static long fetchStaticDefaultDisplay() {
-        if(0==staticDefaultDisplay) {
-            synchronized (X11Util.class) {
-                if(0==staticDefaultDisplay) {
-                    NativeWindowFactory.getDefaultFactory().getToolkitLock().lock();
-                    try {
-                        staticDefaultDisplay = X11Lib.XOpenDisplay(null);
-                        if(0==staticDefaultDisplay) {
-                            throw new NativeWindowException("Unable to create a static default display connection");
-                        }
-                        staticDefaultDisplayXineramaEnable = X11Lib.XineramaEnabled(staticDefaultDisplay);
-                    } finally {
-                        NativeWindowFactory.getDefaultFactory().getToolkitLock().unlock();
-                    }
-                }
-            }
-        }
-        return staticDefaultDisplay;
-    }
-
-    /** Returns the global static default display connection, read the toolkit lock/unlock
-      * requirements {@link X11Util above} for synchronization. */
-    public static long getStaticDefaultDisplay() {
-        return fetchStaticDefaultDisplay();
-    }
-
     /** Returns the global static default display connection, read the toolkit lock/unlock
       * requirements {@link X11Util above} for synchronization. */
-    public static boolean isXineramaEnabledOnStaticDefaultDisplay() {
-        fetchStaticDefaultDisplay();
-        return staticDefaultDisplayXineramaEnable;
+    public static boolean isXineramaEnabledOnThreadLocalDefaultDisplay() {
+        long dpy = getThreadLocalDefaultDisplay();
+        return X11Lib.XineramaEnabled(dpy);
     }
 
-
     /** Returns this thread current default display. */
     public static long getThreadLocalDefaultDisplay() {
         Long dpyL = (Long) currentDisplayAssociation.get();
diff --git a/src/nativewindow/classes/javax/media/nativewindow/ToolkitLock.java b/src/nativewindow/classes/javax/media/nativewindow/ToolkitLock.java
index 27e59d8c8..6f83896fa 100644
--- a/src/nativewindow/classes/javax/media/nativewindow/ToolkitLock.java
+++ b/src/nativewindow/classes/javax/media/nativewindow/ToolkitLock.java
@@ -47,8 +47,9 @@ package javax.media.nativewindow;
     <PRE>
     NativeWindowFactory.getDefaultFactory().getToolkitLock().lock();
     try {
-      long displayHandle = X11Util.getStaticDefaultDisplay();
-      ...
+      long displayHandle = X11Util.getThreadLocalDefaultDisplay();
+      ... some code dealing with shared resources 
+      ... ie the window surface
     } finally {
       NativeWindowFactory.getDefaultFactory().getToolkitLock().unlock();
     }
diff --git a/src/nativewindow/classes/javax/media/nativewindow/x11/X11GraphicsScreen.java b/src/nativewindow/classes/javax/media/nativewindow/x11/X11GraphicsScreen.java
index f434050f2..03121dfaa 100644
--- a/src/nativewindow/classes/javax/media/nativewindow/x11/X11GraphicsScreen.java
+++ b/src/nativewindow/classes/javax/media/nativewindow/x11/X11GraphicsScreen.java
@@ -74,13 +74,8 @@ public class X11GraphicsScreen extends DefaultGraphicsScreen implements Cloneabl
     }
 
     private static int fetchScreen(int screen) {
-        NativeWindowFactory.getDefaultFactory().getToolkitLock().lock();
-        try {
-            if(!com.sun.nativewindow.impl.x11.X11Util.isXineramaEnabledOnStaticDefaultDisplay()) {
-                return screen;
-            }
-        } finally {
-            NativeWindowFactory.getDefaultFactory().getToolkitLock().unlock();
+        if(!com.sun.nativewindow.impl.x11.X11Util.isXineramaEnabledOnThreadLocalDefaultDisplay()) {
+            return screen;
         }
         return 0;
     }