Fix Bug 669: Recursive GLContext makeCurrent()/release()

Culprit:
  GLContext's makeCurrent() didn't clear the boolean flag 'unlockContextAndSurface'
  in case the context is already current (-> recursion).
  Above case was detected within a code block tailed by a finally block,
  which acted on mentioned flag, i.e. called lock.unlock() and hence decremented the lock count
  even though the method return w/ successful state.

  Fixed.

Added debug code:
  GLContext.release() debug code (DEBUG | TRACE_SWITCH),
  recording stack trace of last release() call, which is dumped in case no current was current.

Added 2 unit tests:
  - Simple recursive GLContext makeCurrent()/release() from within GLEventListener's display().
    Test also validates lock count and lock ownership.

  - GLAutoDrawable display() of another GLAutoDrawable
    from within GLEventListener's display(..).

1 files changed, 11 insertions, 0 deletions

diff --git a/src/jogl/classes/javax/media/opengl/GLContext.java b/src/jogl/classes/javax/media/opengl/GLContext.java
index 8cc29f1f2..455f2d70d 100644
--- a/src/jogl/classes/javax/media/opengl/GLContext.java
+++ b/src/jogl/classes/javax/media/opengl/GLContext.java
@@ -103,6 +103,7 @@ public abstract class GLContext {
   
   public static final boolean DEBUG = Debug.debug("GLContext");
   public static final boolean TRACE_SWITCH = Debug.isPropertyDefined("jogl.debug.GLContext.TraceSwitch", true);
+  public static final boolean DEBUG_TRACE_SWITCH = DEBUG || TRACE_SWITCH;  
 
   /** Reflects property jogl.debug.DebugGL. If true, the debug pipeline is enabled at context creation. */
   public static final boolean DEBUG_GL = Debug.isPropertyDefined("jogl.debug.DebugGL", true);
@@ -414,6 +415,16 @@ public abstract class GLContext {
     }
   }
 
+  /** Returns a String representation of the {@link #makeCurrent()} result. */
+  public static final String makeCurrentResultToString(int res) {
+      switch(res) {
+          case CONTEXT_NOT_CURRENT:   return "CONTEXT_NOT_CURRENT";
+          case CONTEXT_CURRENT:       return "CONTEXT_CURRENT";
+          case CONTEXT_CURRENT_NEW:   return "CONTEXT_NOT_CURRENT";
+          default: return "INVALID_VALUE";
+      }
+  }
+
   /**
    * Sets the thread-local variable returned by {@link #getCurrent}
    * and has no other side-effects. For use by third parties adding