williamr@2: /**
williamr@2: * Copyright (c) 2004-2009 Nokia Corporation and/or its subsidiary(-ies).
williamr@2: * All rights reserved.
williamr@2: * This component and the accompanying materials are made available
williamr@2: * under the terms of the License "Symbian Foundation License v1.0" to Symbian Foundation members and "Symbian Foundation End User License Agreement v1.0" to non-members
williamr@2: * which accompanies this distribution, and is available
williamr@2: * at the URL "http://www.symbianfoundation.org/legal/licencesv10.html".
williamr@2: *
williamr@2: * Initial Contributors:
williamr@2: * Nokia Corporation - initial contribution.
williamr@2: *
williamr@2: * Contributors:
williamr@2: *
williamr@2: * Description:
williamr@2: *
williamr@2: */
williamr@2: 
williamr@2: 
williamr@2: 
williamr@2: 
williamr@2: 
williamr@2: /**
williamr@2:  @file MetaType.h
williamr@2:  @internalTechnology
williamr@2: */
williamr@2: 
williamr@2: #if (!defined METATYPE_H)
williamr@2: #define METATYPE_H
williamr@2: 
williamr@2: #include <e32base.h>
williamr@2: #include <e32std.h>
williamr@2: 
williamr@2: namespace Meta
williamr@2: {
williamr@2: 
williamr@2: template<class TYPE> class TMeta;
williamr@2: typedef TMeta<TInt> TMetaNumber;
williamr@2: typedef TMeta<TTime> TMetaTime;
williamr@2: 
williamr@2: class MMetaType
williamr@2: /**
williamr@2: 
williamr@2: Abstract interface of a helper meta type. A meta type is responsible for handling
williamr@2: a particular type. A meta type knows how to copy an object of the type, store it
williamr@2: in a descriptor, load, etc, etc.
williamr@2: 
williamr@2: @internalComponent
williamr@2: @released since v9.0 */
williamr@2:     {
williamr@2: public:
williamr@2: 	virtual TInt Load(TPtrC8& aBuffer) = 0;
williamr@2: 	virtual TInt Store(TDes8& aBuffer) const = 0;
williamr@2:     virtual void Copy(const TAny* aData) = 0;
williamr@2: 	virtual TInt Length() const = 0;
williamr@2:     };
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: class TMeta : public MMetaType
williamr@2: /**
williamr@2: 
williamr@2: Implementation of MMetaType for simple types (e.g. symbian T-types).
williamr@2: 
williamr@2: @internalComponent
williamr@2: @released since v9.0 */
williamr@2:     {
williamr@2: public:
williamr@2:     inline static MMetaType* NewL(const TAny* aMem, const TAny* aData);
williamr@2: 
williamr@2: public:
williamr@2: 	virtual TInt Load(TPtrC8& aBuffer);
williamr@2: 	virtual TInt Store(TDes8& aBuffer) const;
williamr@2:     virtual void Copy(const TAny* aData);
williamr@2: 	virtual TInt Length() const;
williamr@2: 
williamr@2: protected:
williamr@2:     TMeta(const TAny* aData);
williamr@2: 
williamr@2: private:
williamr@2:     const TYPE* iData;
williamr@2:     };
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: class TMetaObject : public MMetaType
williamr@2: /**
williamr@2: 
williamr@2: Implementation of MMetaType for meta objects
williamr@2: 
williamr@2: @internalComponent
williamr@2: @released since v9.0 */
williamr@2: 	{
williamr@2: public:
williamr@2:     inline static MMetaType* NewL(const TAny* aMem, const TAny* aData);
williamr@2: 
williamr@2: public:
williamr@2: 	virtual TInt Load(TPtrC8& aBuffer);
williamr@2: 	virtual TInt Store(TDes8& aBuffer) const;
williamr@2:     virtual void Copy(const TAny* aData);
williamr@2: 	virtual TInt Length() const;
williamr@2: 
williamr@2: protected:
williamr@2:     TMetaObject(const TAny* aData);
williamr@2: 
williamr@2: private:
williamr@2:     TYPE* iData;
williamr@2: 	};
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: class TMetaObjectPtr : public MMetaType
williamr@2: /**
williamr@2: 
williamr@2: Implementation of MMetaType for meta pointers to objects that are never created
williamr@2: 
williamr@2: @internalComponent
williamr@2: @released since v9.0 */
williamr@2: 	{
williamr@2: public:
williamr@2:     inline static MMetaType* NewL(const TAny* aMem, const TAny* aData);
williamr@2: 
williamr@2: public:
williamr@2: 	virtual TInt Load(TPtrC8& aBuffer);
williamr@2: 	virtual TInt Store(TDes8& aBuffer) const;
williamr@2:     virtual void Copy(const TAny* aData);
williamr@2: 	virtual TInt Length() const;
williamr@2: 
williamr@2: protected:
williamr@2:     TMetaObjectPtr(const TAny* aData);
williamr@2: 
williamr@2: private:
williamr@2:     TYPE** iData;
williamr@2: 	};
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: class TMetaPtr : public MMetaType
williamr@2: /**
williamr@2: 
williamr@2: Implementation of MMetaType for pointers to meta objects
williamr@2: 
williamr@2: @internalComponent
williamr@2: @released since v9.0 */
williamr@2: 	{
williamr@2: public:
williamr@2:     inline static MMetaType* NewL(const TAny* aMem, const TAny* aData);
williamr@2: 
williamr@2: 	virtual TInt Load(TPtrC8& aBuffer);
williamr@2: 	virtual TInt Store(TDes8& aBuffer) const;
williamr@2:     virtual void Copy(const TAny* aData);
williamr@2: 	virtual TInt Length() const;
williamr@2: 
williamr@2: protected:
williamr@2:     TMetaPtr(const TAny* aData);
williamr@2: 
williamr@2: private:
williamr@2:     TYPE** iData;
williamr@2: 	};
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: MMetaType* TMeta<TYPE>::NewL(const TAny* aMem, const TAny* aData)
williamr@2: /**
williamr@2:  * Instantiates a meta type of a particular type.
williamr@2:  * Used for attribure registration (in the data v-table).
williamr@2:  */
williamr@2:     {
williamr@2:     return ::new ((TUint8*)aMem) TMeta<TYPE>(aData);
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: inline TMeta<TYPE>::TMeta(const TAny* aData)
williamr@2: :    iData((TYPE*)aData)
williamr@2: /**
williamr@2:  * Constructor
williamr@2:  */
williamr@2:     {
williamr@2:     __ASSERT_DEBUG(iData!=NULL,User::Panic(_L("TMetaType"),KErrArgument));
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: TInt TMeta<TYPE>::Load(TPtrC8& aBuffer)
williamr@2: /**
williamr@2:  * Loads content of a meta object (in iData) from a descriptor
williamr@2:  */
williamr@2:     {
williamr@2: 	TInt len = Length();
williamr@2: 	if (aBuffer.Length() < len)
williamr@2: 		{
williamr@2: 		return KErrArgument;
williamr@2: 		}
williamr@2:     Mem::Copy((TYPE*)iData,aBuffer.Ptr(),len);
williamr@2: 	aBuffer.Set(aBuffer.Ptr()+len, aBuffer.Length()-len); //update pointer
williamr@2: 	return KErrNone;
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: TInt TMeta<TYPE>::Store(TDes8& aBuffer) const
williamr@2: /**
williamr@2:  * Stores content of a meta object (in iData) to a descriptor
williamr@2:  */
williamr@2:     {
williamr@2: 	TInt len = Length();
williamr@2: 	if (aBuffer.MaxLength() - aBuffer.Length() < len)
williamr@2: 		{
williamr@2: 		return KErrOverflow;
williamr@2: 		}
williamr@2: 	aBuffer.Append((TUint8*)iData, len);
williamr@2: 	return KErrNone;
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: void TMeta<TYPE>::Copy(const TAny* aData)
williamr@2: /**
williamr@2:  * Copies content of a meta object (in aData) into another meta object (in iData).
williamr@2:  * This is a MMetaType implementation for simple (T) types so it just copies the memory.
williamr@2:  */
williamr@2:     {
williamr@2:     Mem::Copy((TAny*)iData,aData,Length());
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: TInt TMeta<TYPE>::Length() const
williamr@2: /**
williamr@2:  * Returns the length of the handled meta object.
williamr@2:  */
williamr@2:     {
williamr@2:     return sizeof(TYPE);
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: MMetaType* TMetaObject<TYPE>::NewL(const TAny* aMem, const TAny* aData)
williamr@2: /**
williamr@2:  * Instantiates a meta type of a particular type.
williamr@2:  * Used for attribure registration (in the data v-table).
williamr@2:  */
williamr@2:     {
williamr@2:     return ::new ((TUint8*)aMem) TMetaObject<TYPE>(aData);
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: inline TMetaObject<TYPE>::TMetaObject(const TAny* aData)
williamr@2: :    iData((TYPE*)aData)
williamr@2: /**
williamr@2:  * Constructor
williamr@2:  */
williamr@2:     {
williamr@2:     __ASSERT_DEBUG(iData!=NULL,User::Panic(_L("TMetaType"),KErrArgument));
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: TInt TMetaObject<TYPE>::Load(TPtrC8& aBuffer)
williamr@2: /**
williamr@2:  * Loads content of a meta object (in iData) from a descriptor
williamr@2:  */
williamr@2:    {
williamr@2: 	TInt err = iData->GetTypeId().Check( aBuffer );
williamr@2: 	return err == KErrNone ? iData->Load(aBuffer) : err;
williamr@2:    }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: TInt TMetaObject<TYPE>::Store(TDes8& aBuffer) const
williamr@2: /**
williamr@2:  * Stores content of a meta object (in iData) to a descriptor
williamr@2:  */
williamr@2:     {
williamr@2: 	return iData->Store(aBuffer);
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: void TMetaObject<TYPE>::Copy(const TAny* aData)
williamr@2: /**
williamr@2:  * Copies content of a meta object (in aData) into another meta object (in iData).
williamr@2:  */
williamr@2:     {
williamr@2: 	iData->Copy(*((TYPE*)aData));
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: TInt TMetaObject<TYPE>::Length() const
williamr@2: /**
williamr@2:  * Returns the length of the handled meta object.
williamr@2:  */
williamr@2:     {
williamr@2: 	return iData->Length();
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: MMetaType* TMetaObjectPtr<TYPE>::NewL(const TAny* aMem, const TAny* aData)
williamr@2: /**
williamr@2:  * Instantiates a meta type of a particular type.
williamr@2:  * Used for attribure registration (in the data v-table).
williamr@2:  */
williamr@2:     {
williamr@2:     return ::new ((TUint8*)aMem) TMetaObjectPtr<TYPE>(aData);
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: inline TMetaObjectPtr<TYPE>::TMetaObjectPtr(const TAny* aData)
williamr@2: :    iData((TYPE**)aData)
williamr@2: /**
williamr@2:  * Constructor
williamr@2:  */
williamr@2:     {
williamr@2:     __ASSERT_DEBUG(iData!=NULL,User::Panic(_L("TMetaType"),KErrArgument));
williamr@2:     __ASSERT_DEBUG(*iData!=NULL,User::Panic(_L("TMetaType"),KErrArgument));
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: TInt TMetaObjectPtr<TYPE>::Load(TPtrC8& aBuffer)
williamr@2: /**
williamr@2:  * Loads content of a meta object (in iData) from a descriptor
williamr@2:  */
williamr@2:    {
williamr@2: 	TInt err = (*iData)->GetTypeId().Check( aBuffer );
williamr@2: 	return err == KErrNone ? (*iData)->Load(aBuffer) : err;
williamr@2:    }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: TInt TMetaObjectPtr<TYPE>::Store(TDes8& aBuffer) const
williamr@2: /**
williamr@2:  * Stores content of a meta object (in iData) to a descriptor
williamr@2:  */
williamr@2:     {
williamr@2: 	return (*iData)->Store(aBuffer);
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: void TMetaObjectPtr<TYPE>::Copy(const TAny* aData)
williamr@2: /**
williamr@2:  * Copies content of a meta object (in aData) into another meta object (in iData).
williamr@2:  */
williamr@2:     {
williamr@2: 	(*iData)->Copy(*((TYPE*)aData));
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: TInt TMetaObjectPtr<TYPE>::Length() const
williamr@2: /**
williamr@2:  * Returns the length of the handled meta object.
williamr@2:  */
williamr@2:     {
williamr@2: 	return (*iData)->Length();
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: inline TMetaPtr<TYPE>::TMetaPtr(const TAny* aData)
williamr@2: :    iData((TYPE**)aData)
williamr@2: /**
williamr@2:  * Constructor
williamr@2:  */
williamr@2:     {
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: MMetaType* TMetaPtr<TYPE>::NewL(const TAny* aMem, const TAny* aData)
williamr@2: /**
williamr@2:  * Instantiates a meta type of a particular type.
williamr@2:  * Used for attribure registration (in the data v-table).
williamr@2:  */
williamr@2:     {
williamr@2:     return ::new ((TUint8*)aMem) TMetaPtr<TYPE>(aData);
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: TInt TMetaPtr<TYPE>::Load(TPtrC8& aBuffer)
williamr@2: /**
williamr@2:  * Loads content of a meta object (in iData) from a descriptor
williamr@2:  */
williamr@2:     {
williamr@2: 	if (aBuffer.Length() < (TInt) sizeof(TUint32))
williamr@2: 		{
williamr@2: 		return KErrArgument;
williamr@2: 		}
williamr@2: 
williamr@2: 	// Check for a NULL pointer when stored (First four bytes == 0)
williamr@2: 	if (*((TUint32*)aBuffer.Ptr()) == 0)
williamr@2: 		{
williamr@2: 		// The pointer was NULL when it was stored
williamr@2: 		aBuffer.Set(aBuffer.Ptr() + sizeof(TUint32), aBuffer.Length() - sizeof(TUint32));
williamr@2: 		if (*iData != NULL)
williamr@2: 			{
williamr@2: 			delete *iData;
williamr@2: 			*iData = NULL;
williamr@2: 			}
williamr@2: 		return KErrNone;
williamr@2: 		}
williamr@2: 
williamr@2: 	if (*iData == NULL)
williamr@2: 		{
williamr@2: 		TRAPD(ret, *iData = reinterpret_cast<TYPE*>(TYPE::LoadL(aBuffer)));
williamr@2: 		return ret;
williamr@2: 		}
williamr@2: 	else
williamr@2: 		{
williamr@2: 		return (*iData)->Load(aBuffer);
williamr@2: 		}
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: TInt TMetaPtr<TYPE>::Store(TDes8& aBuffer) const
williamr@2: /**
williamr@2:  * Stores content of a meta object (in iData) to a descriptor
williamr@2:  */
williamr@2:     {
williamr@2: 	if (*iData == NULL)
williamr@2: 		{
williamr@2: 		const TUint32 KNullInt = 0;
williamr@2: 		aBuffer.Append((TUint8*)&KNullInt, sizeof(TUint32));
williamr@2: 		return KErrNone;
williamr@2: 		}
williamr@2: 	else
williamr@2: 		{
williamr@2: 		return (*iData)->Store(aBuffer);
williamr@2: 		}
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: void TMetaPtr<TYPE>::Copy(const TAny* aData)
williamr@2: /**
williamr@2:  * Copies content of a meta object (in aData) into another meta object (in iData).
williamr@2:  */
williamr@2:     {
williamr@2: 	(*iData)->Copy(*((TYPE*)aData));
williamr@2:     }
williamr@2: 
williamr@2: template<class TYPE>
williamr@2: TInt TMetaPtr<TYPE>::Length() const
williamr@2: /**
williamr@2:  * Returns the length of the handled meta object.
williamr@2:  */
williamr@2:     {
williamr@2: 	if (*iData == NULL)
williamr@2: 		{
williamr@2: 		// Add length of null word (Used to represent a NULL pointer)
williamr@2: 		return sizeof(TUint32);
williamr@2: 		}
williamr@2: 	else
williamr@2: 		{
williamr@2: 		return (*iData)->Length();
williamr@2: 		}
williamr@2:     }
williamr@2: 
williamr@2: } //namespace Meta
williamr@2: 
williamr@2: 
williamr@2: #endif //METATYPE_H