[Java-game-lib-cvs] SF.net SVN: java-game-lib: [2970] trunk/LWJGL/src

[<eli...@us...>]

Revision: 2970
          http://java-game-lib.svn.sourceforge.net/java-game-lib/?rev=2970&view=rev
Author:   elias_naur
Date:     2008-04-06 14:34:22 -0700 (Sun, 06 Apr 2008)

Log Message:
-----------
Linux: Attempt to avoid race condition when tracking Display parent focus

Modified Paths:
--------------
    trunk/LWJGL/src/java/org/lwjgl/opengl/LinuxDisplay.java
    trunk/LWJGL/src/native/linux/org_lwjgl_opengl_Display.c

Modified: trunk/LWJGL/src/java/org/lwjgl/opengl/LinuxDisplay.java
===================================================================
--- trunk/LWJGL/src/java/org/lwjgl/opengl/LinuxDisplay.java	2008-04-06 20:56:52 UTC (rev 2969)
+++ trunk/LWJGL/src/java/org/lwjgl/opengl/LinuxDisplay.java	2008-04-06 21:34:22 UTC (rev 2970)
@@ -623,8 +623,6 @@
 	private native static void setInputFocus(long display, long window);
 
 	private void processEvents() {
-		if (!focused && parent != null && parent.isFocusOwner())
-			setInputFocus(getDisplay(), getWindow());
 		while (LinuxEvent.getPending(getDisplay()) > 0) {
 			event_buffer.nextEvent(getDisplay());
 			long event_window = event_buffer.getWindow();
@@ -742,15 +740,30 @@
 	}
 	
 	private void checkInput() {
-		focused = nGetInputFocus(getDisplay()) == getWindow();
+		long current_focus = nGetInputFocus(getDisplay());
+		focused = current_focus == getWindow();
 		if (focused) {
 			focused_at_least_once = true;
 			acquireInput();
-		} else if (focused_at_least_once) {
-			releaseInput();
+		} else {
+			if (focused_at_least_once)
+				releaseInput();
+			if (parent != null && parent.isFocusOwner()) {
+				// Normally, a real time stamp from an event should be passed to XSetInputFocus instead of CurrentTime, but we don't get timestamps
+				// from awt. Instead we grab the server and check if the focus changed to avoid a race where our window is made unviewable while focusing it.
+				grabServer(getDisplay());
+				try {
+					if (nGetInputFocus(getDisplay()) == current_focus)
+						setInputFocus(getDisplay(), getWindow());
+				} finally {
+					ungrabServer(getDisplay());
+				}
+			}
 		}
 	}
 	static native long nGetInputFocus(long display);
+	private static native void grabServer(long display);
+	private static native void ungrabServer(long display);
 
 	private void releaseInput() {
 		if (isLegacyFullscreen() || input_released)

Modified: trunk/LWJGL/src/native/linux/org_lwjgl_opengl_Display.c
===================================================================
--- trunk/LWJGL/src/native/linux/org_lwjgl_opengl_Display.c	2008-04-06 20:56:52 UTC (rev 2969)
+++ trunk/LWJGL/src/native/linux/org_lwjgl_opengl_Display.c	2008-04-06 21:34:22 UTC (rev 2970)
@@ -327,14 +327,20 @@
 	return win;
 }
 
+JNIEXPORT void JNICALL Java_org_lwjgl_opengl_LinuxDisplay_grabServer(JNIEnv *env, jclass unused, jlong display) {
+	Display *disp = (Display *)(intptr_t)display;
+	XGrabServer(disp);
+}
+
+JNIEXPORT void JNICALL Java_org_lwjgl_opengl_LinuxDisplay_ungrabServer(JNIEnv *env, jclass unused, jlong display) {
+	Display *disp = (Display *)(intptr_t)display;
+	XUngrabServer(disp);
+}
+
 JNIEXPORT void JNICALL Java_org_lwjgl_opengl_LinuxDisplay_setInputFocus(JNIEnv *env, jclass clazz, jlong display, jlong window_ptr) {
 	Display *disp = (Display *)(intptr_t)display;
 	Window window = (Window)window_ptr;
-	// Normally, a real time stamp from an event should be passed instead of CurrentTime, but we don't get timestamps
-	// from awt. Instead we grab the server before and ungrab it after the request
-	XGrabServer(disp);
 	XSetInputFocus(disp, window, RevertToParent, CurrentTime);
-	XUngrabServer(disp);
 }
 
 JNIEXPORT jlong JNICALL Java_org_lwjgl_opengl_LinuxDisplay_nCreateWindow(JNIEnv *env, jclass clazz, jlong display, jint screen, jobject peer_info_handle, jobject mode, jint window_mode, jint x, jint y, jboolean undecorated, jlong parent_handle) {


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