metadataengine/server/inc/mdsobjectlocklist.h
changeset 0 c53acadfccc6
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/metadataengine/server/inc/mdsobjectlocklist.h	Mon Jan 18 20:34:07 2010 +0200
@@ -0,0 +1,129 @@
+/*
+* Copyright (c) 2005-2009 Nokia Corporation and/or its subsidiary(-ies). 
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of "Eclipse Public License v1.0"
+* which accompanies this distribution, and is available
+* at the URL "http://www.eclipse.org/legal/epl-v10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - initial contribution.
+*
+* Contributors:
+*
+* Description:  Object locking features*
+*/
+
+#ifndef __MDSOBJECTLOCKLIST_H__
+#define __MDSOBJECTLOCKLIST_H__
+
+#include <e32base.h>
+
+#include "mdscommoninternal.h"
+
+class TMdSLockEntry;
+class CMdSServerSession;
+class CMdsNamespaceDef;
+
+/**
+* Metadata object locking.
+* When opening objects for modifications, objects
+* is locked so that no other session can modify the
+* same object at same time.
+*/
+class CMdSObjectLockList : public CBase
+    {
+    public: // Constructors and destructor
+
+        virtual ~CMdSObjectLockList();
+
+        static CMdSObjectLockList* NewL();
+        static CMdSObjectLockList* NewLC();
+
+    private: // Private constructors
+
+        void ConstructL();
+
+    public: // Public functions
+        /**
+        * Locks object for modifying.
+        * @param aSession   Session where object is being modified.
+        * @param aNamespace Object's owner namespace
+        * @param aObjId     Object id that is being modified.
+        * @return           Returns whether object could be locked or not.
+        */
+        void LockObjectL( const CMdSServerSession& aSession, 
+        		const CMdsNamespaceDef& aNamespace, const TItemId aObjectId );
+
+        /**
+        * Unlocks all locked objects of particular session.
+        * @param aSession   Session which locked objects are to be released.
+        */
+        void UnlockBySession( const CMdSServerSession& aSession );
+
+        /**
+        * Unlocks locked object by Id.
+        * @param aNamespace Object's owner namespace
+        * @param aObjId     Object id that is being modified.
+        */
+        void UnlockById( const CMdsNamespaceDef& aNamespace, 
+        		const TItemId aObjectId );
+
+        /**
+        * Checks if object is locked for modifying.
+        * @param aNamespace Object's owner namespace
+        * @param aObjId     An objects id which is going to be checked.
+        * @return           <code>ETrue</code> if locked.
+        *                   <code>EFalse</code> if not.
+        */
+        TBool IsLocked( const CMdsNamespaceDef& aNamespace, 
+        		const TItemId aObjectId ) const;
+
+    	/**
+    	 * Empties the object lock list.
+    	 */
+        void Reset();
+
+	protected:
+		TInt Find( const CMdsNamespaceDef& aNamespace, 
+				const TItemId aObjectId ) const;
+
+    private:
+        /**
+         * Array which have the locked objects.
+         */
+        RArray<TMdSLockEntry> iLockListArray;
+    };
+
+/**
+ * Internal data structure for storing information about locked objects.
+ */
+class TMdSLockEntry
+    {
+    public:
+        /**
+    	* Constructs a new lock list object.
+        *
+    	* @param aSession   session to which object id belongs
+        * @param aNamespace Object's owner namespace
+    	* @param aId        object id being modified
+    	*/
+    	TMdSLockEntry( const CMdSServerSession* aSession, 
+    			const CMdsNamespaceDef& aNamespace, const TItemId aId )
+    	: iSession( aSession ) , iNamespace( aNamespace ), iId( aId )
+    	    {}
+
+		static TInt Compare( const TMdSLockEntry& aFirst, 
+				const TMdSLockEntry& aSecond );
+    public:
+        /* Session where object is being modified */
+        const CMdSServerSession* iSession;
+
+        /* Object's owner namespace */
+        const CMdsNamespaceDef& iNamespace;
+
+        /* Object's id which is being modified */
+        TItemId iId;
+    };
+
+#endif  // __MDSOBJECTLOCKLIST_H__