Testcase TestRegionAndGCFailure

[Phil Muldoon <pmuldoon at redhat dot com>]

I added this into the testsuite (with a brokenXXX so it would not cause 
the test-suite to fail).

I suddenly realized why none of our test-cases in isolation could 
reproduce on the way home tonight.  We were not creating the graphical 
context in concert with the region. Both are needed to cause the smash 
(in theory, I cannot cause the smash to happen with just one or the 
other). On FC6 this reduces the smash to a couple lines of code. I 
suspect it could be reduced further. You can thank the traffic on I-565 
home tonight for this little bit of inspiration ;)

For some reason this will occasionally pass without a smash. I've no 
idea why.

Regards

Phil
Index: frysk-gui/frysk/gui/test/TestRegionAndGCFailure.java
diff -u /dev/null frysk-gui/frysk/gui/test/TestRegionAndGCFailure.java:1.1
--- /dev/null	Wed Oct 25 02:33:55 2006
+++ frysk-gui/frysk/gui/test/TestRegionAndGCFailure.java	Wed Oct 25 02:11:59 2006
@@ -0,0 +1,127 @@
+// This file is part of the program FRYSK.
+//
+// Copyright 2006, Red Hat Inc.
+//
+// FRYSK is free software; you can redistribute it and/or modify it
+// under the terms of the GNU General Public License as published by
+// the Free Software Foundation; version 2 of the License.
+//
+// FRYSK is distributed in the hope that it will be useful, but
+// WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// General Public License for more details.
+// type filter text
+// You should have received a copy of the GNU General Public License
+// along with FRYSK; if not, write to the Free Software Foundation,
+// Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+// 
+// In addition, as a special exception, Red Hat, Inc. gives You the
+// additional right to link the code of FRYSK with code not covered
+// under the GNU General Public License ("Non-GPL Code") and to
+// distribute linked combinations including the two, subject to the
+// limitations in this paragraph. Non-GPL Code permitted under this
+// exception must only link to the code of FRYSK through those well
+// defined interfaces identified in the file named EXCEPTION found in
+// the source code files (the "Approved Interfaces"). The files of
+// Non-GPL Code may instantiate templates or use macros or inline
+// functions from the Approved Interfaces without causing the
+// resulting work to be covered by the GNU General Public
+// License. Only Red Hat, Inc. may make changes or additions to the
+// list of Approved Interfaces. You must obey the GNU General Public
+// License in all respects for all of the FRYSK code and other code
+// used in conjunction with FRYSK except the Non-GPL Code covered by
+// this exception. If you modify this file, you may extend this
+// exception to your version of the file, but you are not obligated to
+// do so. If you do not wish to provide this exception without
+// modification, you must delete this exception statement from your
+// version and license this file solely under the GPL without
+// exception.
+
+package frysk.gui.test;
+
+import frysk.junit.TestCase;
+
+import org.gnu.gtk.Gtk;
+import org.gnu.gtk.ScrolledWindow;
+import org.gnu.gtk.TextView;
+import org.gnu.gtk.VBox;
+import org.gnu.gdk.Window;
+import org.gnu.gdk.Drawable;
+import org.gnu.gdk.GC;
+
+/**
+ * 
+ * Creates a testcase for BZ 3116. 
+ * 
+ * Use of Regions and GC (Graphics Context) 
+ * can cause pointer smash.
+ * 
+ * @author pmuldoon
+ *
+ */
+public class TestRegionAndGCFailure extends TestCase {
+
+  public void setUp() 
+  {
+    Gtk.init(new String[] {});
+  }
+
+  public void testRegionAndGCFailure()
+  {
+	
+	// Don't want it to bust testsuite, so remove
+    // below to see crash.
+    if (brokenXXX (3116))
+      return;
+    
+    // Top level window.
+    org.gnu.gtk.Window parent = new org.gnu.gtk.Window();
+    VBox box = new VBox(false,0);
+    parent.add(box);
+    
+    // Scrolled window to hold our TextView.
+    ScrolledWindow sw = new ScrolledWindow();
+    box.add(sw);
+    
+    // TextView.
+    TextView tv = new TextView();
+    sw.addWithViewport(tv);
+    
+    // Have to do this show() so GC will work.
+    parent.showAll();
+    
+    // Get our org.gnu.gdk.Window from the textview.
+    // This is simply the easiest way to get a workable
+    // instance of a GDK window, which is critical to the test.
+    Window drawingArea = tv.getWindow();
+    
+    // Get Graphical Context.
+    GC myContext = new GC((Drawable) drawingArea);
+
+    // Draw rectangle.
+    drawingArea.drawRectangle(myContext, true, 0, 0,
+				drawingArea.getWidth(), drawingArea.getHeight());
+
+    int minY = 0, maxY = 0;
+    
+    // Get the y coordinates for the top and bottom of the window. This creates
+    // an anonymous Region object, that will be scheduled for GC after these 
+    // operations complete. It should be the final piece to get the smash.
+   	minY = drawingArea.getClipRegion().getClipbox().getY();
+   	maxY = minY + drawingArea.getClipRegion().getClipbox().getHeight();
+   	
+   	// GC .. should go BOOM!
+   	System.gc();
+   	
+   	// Create an idle situation.
+   	try {
+		Thread.sleep(1000);
+	} catch (InterruptedException e) {
+		fail(e.getMessage());
+	}
+ 
+    // have to do this so ecj does not barf
+    maxY = minY + maxY;
+
+  }
+}
\ No newline at end of file