Segfault if cSkinDisplayMessage is replaced by another display object

[udo_richter at gmx.de (Udo Richter)]

Udo Richter wrote:
> The attached patch changes cSkins::Message() by only checking the 
> existence of cSkinDisplay::Current(). If no current cSkinDisplay exists, 
> any old displayMessage object is deleted and a new one is created.

I've found another segfault related to displayMessage. If VDR gets 
terminated while a message is displayed, the delete displayMessage in 
cSkins::~cSkins() takes action. But since Skins is a global variable, 
~cSkins() will be called very late within the shutdown process, at a 
time when skins and OSD are already free'd. In case of skin plugins, the 
plugin program code is even already unloaded at that point, causing a 
segfault.

The attached patch cleans up any remaining displayMessage before the 
cSkin objects are freed.

Cheers,

Udo

-------------- next part --------------
--- skins.h.orig	2006-12-05 17:35:51.724023920 +0100
+++ skins.h	2006-12-05 17:37:27.589486448 +0100
@@ -360,6 +360,8 @@
        ///< Processes the first queued message, if any.
   void Flush(void);
        ///< Flushes the currently active cSkinDisplay, if any.
+  virtual void Clear(void);
+       ///< Free up all registered skins
   };
 
 extern cSkins Skins;
--- skins.c.orig	2006-12-05 17:47:10.949575792 +0100
+++ skins.c	2006-12-05 18:05:27.597505048 +0100
@@ -358,3 +358,12 @@
   if (cSkinDisplay::Current())
      cSkinDisplay::Current()->Flush();
 }
+
+void cSkins::Clear(void)
+{
+  if (displayMessage) {
+     delete displayMessage;
+     displayMessage = NULL;
+     }
+  cList<cSkin>::Clear();
+}