Copy the KDE 3.5 branch to branches/trinity for new KDE 3.5 features.

BUG:215923


git-svn-id: svn://anonsvn.kde.org/home/kde/branches/trinity/kdelibs@1054174 283d02a7-25f6-0310-bc7c-ecb5cbfe19da

1 files changed, 139 insertions, 0 deletions

diff --git a/kdecore/kstaticdeleter.h b/kdecore/kstaticdeleter.h
new file mode 100644
index 000000000..ee3e5755c
--- /dev/null
+++ b/kdecore/kstaticdeleter.h
@@ -0,0 +1,139 @@
+/*
+ * This file is part of the KDE Libraries
+ * Copyright (C) 2000 Stephan Kulow <coolo@kde.org>
+ *               2001 KDE Team
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public License
+ * along with this library; see the file COPYING.LIB.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ *
+ */
+
+#ifndef _KSTATIC_DELETER_H_
+#define _KSTATIC_DELETER_H_
+
+#include <kglobal.h>
+
+/**
+ * Static deleters are used to manage static resources. They can register
+ * themselves with KGlobal. KGlobal will call destructObject() when
+ * KGlobal::deleteStaticDeleters() is called or when it the process
+ * finishes.
+ *
+ * @see KStaticDeleter
+ * @see KGlobal::registerStaticDeleter()
+ * @see KGlobal::unregisterStaticDeleter()
+ * @see KGlobal::deleteStaticDeleters()
+ */
+class KDECORE_EXPORT KStaticDeleterBase {
+public:
+    virtual ~KStaticDeleterBase() { }
+    /**
+     * Should destruct the resources managed by this KStaticDeleterBase.
+     * Usually you also want to call it in your destructor.
+     * @see KGlobal::deleteStaticDeleters()
+     */
+    virtual void destructObject();
+};
+
+/**
+ * Little helper class to clean up static objects that are
+ * held as pointer.
+ * When the library is unloaded, or the app terminated, all static deleters
+ * are destroyed, which in turn destroys those static objects properly.
+ * There are some rules which you should accept in the KStaticDeleter managed
+ * class:
+ * @li Don't rely on the global reference variable in the destructor of the 
+ * object, it will be '0' at destruction time.
+ * @li Don't rely on other KStaticDeleter managed objects in the destructor 
+ * of the object, because it may be destroyed before your destructor get called.
+ * This one can be tricky, because you might not know that you actually use a
+ * KStaticDeleter managed class. So try to keep your destructor simple.
+ *
+ * A typical use is
+ * \code
+ * static KStaticDeleter<MyClass> sd;
+ *
+ * MyClass &MyClass::self() {
+ *   if (!_self) { sd.setObject(_self, new MyClass()); }
+ *   return *_self;
+ * }
+ * \endcode
+ */
+template<class type> class KStaticDeleter : public KStaticDeleterBase {
+public:
+    KStaticDeleter() { deleteit = 0; globalReference = 0; array = false; }
+    /**
+     * Sets the object to delete and registers the object to be
+     * deleted to KGlobal. If the given object is 0, the former
+     * registration is unregistered.
+     * @param obj the object to delete
+     * @param isArray tells the destructor to delete an array instead of an object
+     * @deprecated See the other setObject variant.
+     **/
+    KDE_DEPRECATED type *setObject( type *obj, bool isArray = false) {
+        deleteit = obj;
+        globalReference = 0;
+	array = isArray;
+	if (obj)
+            KGlobal::registerStaticDeleter(this);
+	else
+	    KGlobal::unregisterStaticDeleter(this);
+        return obj;
+    }
+    /**
+     * Sets the object to delete and registers the object to be
+     * deleted to KGlobal. If the given object is 0, the former
+     * registration is unregistered.
+     * @param globalRef the static pointer where this object is stored
+     * This pointer will be reset to 0 after deletion of the object.
+     * @param obj the object to delete
+     * @param isArray tells the destructor to delete an array instead of an object
+     **/
+    type *setObject( type* & globalRef, type *obj, bool isArray = false) {
+        globalReference = &globalRef;
+        deleteit = obj;
+	array = isArray;
+	if (obj)
+            KGlobal::registerStaticDeleter(this);
+	else
+	    KGlobal::unregisterStaticDeleter(this);
+        globalRef = obj;
+	return obj;
+    }
+
+    /**
+     * Destructs the object. This has the same effect as deleting
+     * the KStaticDeleter.
+     */
+    virtual void destructObject() {
+        if (globalReference)
+           *globalReference = 0;
+	if (array)
+	   delete [] deleteit;
+	else
+	   delete deleteit;
+    	deleteit = 0;
+    }
+    virtual ~KStaticDeleter() {
+    	KGlobal::unregisterStaticDeleter(this);
+	destructObject();
+    }
+private:
+    type *deleteit;
+    type **globalReference;
+    bool array;
+};
+
+#endif