Merge lp:~vanvugt/compiz-core/fix-composite-init-fail into lp:compiz-core

[Daniel van Vugt]

Fixed: Composite would fail to initialize even when it was the only
composite window manage running. This was because it leaked its handles
and in the unusual cases where plugin load failures cause other plugins to
unload/reload, composite would fail to init the second time.
(LP: #963465) (LP: #963264) (LP: #833729)

[Sam Spilsbury (smspillaz)]

That's fine.

The XSetSelectionOwner call is probably unnecessary as the protocol does this implicitly. But it doesn't hurt. Bonus points for making a class to wrap the selection atom.

review: Approve

[Alan Griffiths (alan-griffiths)]

review: Approve

=== modified file 'plugins/composite/src/privates.h'
--- plugins/composite/src/privates.h	2012-02-08 10:54:35 +0000
+++ plugins/composite/src/privates.h	2012-03-27 12:21:44 +0000
@@ -103,6 +103,9 @@
 	CompositeFPSLimiterMode FPSLimiterMode;
 
 	CompWindowList withDestroyedWindows;
+
+	Atom cmSnAtom;
+	Window newCmSnOwner;
 };
 
 class PrivateCompositeWindow : WindowInterface

=== modified file 'plugins/composite/src/screen.cpp'
--- plugins/composite/src/screen.cpp	2012-03-23 09:30:55 +0000
+++ plugins/composite/src/screen.cpp	2012-03-27 12:21:44 +0000
@@ -45,9 +45,6 @@
 
 #include <core/timer.h>
 
-#include <cstdlib>
-#include <cstdio>
-
 CompWindow *lastDamagedWindow = 0;
 
 void
@@ -198,26 +195,6 @@
     return priv->damageEvent;
 }
 
-/* TODO - remove these macros, also <cstdio> and <cstdlib> above.
- *
- * We're seeing errors in code that tries to use composite after
- * it fails to initialise.
- *
- * I agree in advance that this macro subverting setFailed() is a
- * horrible hack.  But making the client code either handle errors,
- * or exception neutral, is a LOT of work.
- *
- * This could give us some more immediate feedback on the causes
- * of failure and a better solution.
- *                                             Alan Griffiths
- */
-#define ARG_STRINGIZE(x) ARG_STRINGIZE_(x)
-#define ARG_STRINGIZE_(x) #x
-#define setFailed()\
-do { \
-    std::fputs("error CompositeScreen::CompositeScreen - line " ARG_STRINGIZE(__LINE__) "\n", stderr);\
-    std::exit(EXIT_FAILURE);\
-} while (false)
 
 CompositeScreen::CompositeScreen (CompScreen *s) :
     PluginClassHandler<CompositeScreen, CompScreen, COMPIZ_COMPOSITE_ABI> (s),
@@ -280,11 +257,6 @@
 
 }
 
-#undef ARG_STRINGIZE
-#undef ARG_STRINGIZE_
-#undef setFailed
-
-
 CompositeScreen::~CompositeScreen ()
 {
     priv->paintTimer.stop ();
@@ -310,7 +282,9 @@
     slowAnimations (false),
     pHnd (NULL),
     FPSLimiterMode (CompositeFPSLimiterModeDefault),
-    withDestroyedWindows ()
+    withDestroyedWindows (),
+    cmSnAtom (0),
+    newCmSnOwner (None)
 {
     gettimeofday (&lastRedraw, 0);
     // wrap outputChangeNotify
@@ -321,14 +295,19 @@
 
 PrivateCompositeScreen::~PrivateCompositeScreen ()
 {
+    Display *dpy = screen->dpy ();
+
+    if (cmSnAtom)
+	XSetSelectionOwner (dpy, cmSnAtom, None, CurrentTime);
+
+    if (newCmSnOwner != None)
+	XDestroyWindow (dpy, newCmSnOwner);
 }
 
 bool
 PrivateCompositeScreen::init ()
 {
     Display              *dpy = screen->dpy ();
-    Window               newCmSnOwner = None;
-    Atom                 cmSnAtom = 0;
     Time                 cmSnTimestamp = 0;
     XEvent               event;
     XSetWindowAttributes attr;