epoc32/include/comms-infras/metatype.h
branchSymbian2
changeset 2 2fe1408b6811
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/epoc32/include/comms-infras/metatype.h	Tue Mar 16 16:12:26 2010 +0000
     1.3 @@ -0,0 +1,442 @@
     1.4 +/**
     1.5 +* Copyright (c) 2004-2009 Nokia Corporation and/or its subsidiary(-ies).
     1.6 +* All rights reserved.
     1.7 +* This component and the accompanying materials are made available
     1.8 +* 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
     1.9 +* which accompanies this distribution, and is available
    1.10 +* at the URL "http://www.symbianfoundation.org/legal/licencesv10.html".
    1.11 +*
    1.12 +* Initial Contributors:
    1.13 +* Nokia Corporation - initial contribution.
    1.14 +*
    1.15 +* Contributors:
    1.16 +*
    1.17 +* Description:
    1.18 +*
    1.19 +*/
    1.20 +
    1.21 +
    1.22 +
    1.23 +
    1.24 +
    1.25 +/**
    1.26 + @file MetaType.h
    1.27 + @internalTechnology
    1.28 +*/
    1.29 +
    1.30 +#if (!defined METATYPE_H)
    1.31 +#define METATYPE_H
    1.32 +
    1.33 +#include <e32base.h>
    1.34 +#include <e32std.h>
    1.35 +
    1.36 +namespace Meta
    1.37 +{
    1.38 +
    1.39 +template<class TYPE> class TMeta;
    1.40 +typedef TMeta<TInt> TMetaNumber;
    1.41 +typedef TMeta<TTime> TMetaTime;
    1.42 +
    1.43 +class MMetaType
    1.44 +/**
    1.45 +
    1.46 +Abstract interface of a helper meta type. A meta type is responsible for handling
    1.47 +a particular type. A meta type knows how to copy an object of the type, store it
    1.48 +in a descriptor, load, etc, etc.
    1.49 +
    1.50 +@internalComponent
    1.51 +@released since v9.0 */
    1.52 +    {
    1.53 +public:
    1.54 +	virtual TInt Load(TPtrC8& aBuffer) = 0;
    1.55 +	virtual TInt Store(TDes8& aBuffer) const = 0;
    1.56 +    virtual void Copy(const TAny* aData) = 0;
    1.57 +	virtual TInt Length() const = 0;
    1.58 +    };
    1.59 +
    1.60 +template<class TYPE>
    1.61 +class TMeta : public MMetaType
    1.62 +/**
    1.63 +
    1.64 +Implementation of MMetaType for simple types (e.g. symbian T-types).
    1.65 +
    1.66 +@internalComponent
    1.67 +@released since v9.0 */
    1.68 +    {
    1.69 +public:
    1.70 +    inline static MMetaType* NewL(const TAny* aMem, const TAny* aData);
    1.71 +
    1.72 +public:
    1.73 +	virtual TInt Load(TPtrC8& aBuffer);
    1.74 +	virtual TInt Store(TDes8& aBuffer) const;
    1.75 +    virtual void Copy(const TAny* aData);
    1.76 +	virtual TInt Length() const;
    1.77 +
    1.78 +protected:
    1.79 +    TMeta(const TAny* aData);
    1.80 +
    1.81 +private:
    1.82 +    const TYPE* iData;
    1.83 +    };
    1.84 +
    1.85 +template<class TYPE>
    1.86 +class TMetaObject : public MMetaType
    1.87 +/**
    1.88 +
    1.89 +Implementation of MMetaType for meta objects
    1.90 +
    1.91 +@internalComponent
    1.92 +@released since v9.0 */
    1.93 +	{
    1.94 +public:
    1.95 +    inline static MMetaType* NewL(const TAny* aMem, const TAny* aData);
    1.96 +
    1.97 +public:
    1.98 +	virtual TInt Load(TPtrC8& aBuffer);
    1.99 +	virtual TInt Store(TDes8& aBuffer) const;
   1.100 +    virtual void Copy(const TAny* aData);
   1.101 +	virtual TInt Length() const;
   1.102 +
   1.103 +protected:
   1.104 +    TMetaObject(const TAny* aData);
   1.105 +
   1.106 +private:
   1.107 +    TYPE* iData;
   1.108 +	};
   1.109 +
   1.110 +template<class TYPE>
   1.111 +class TMetaObjectPtr : public MMetaType
   1.112 +/**
   1.113 +
   1.114 +Implementation of MMetaType for meta pointers to objects that are never created
   1.115 +
   1.116 +@internalComponent
   1.117 +@released since v9.0 */
   1.118 +	{
   1.119 +public:
   1.120 +    inline static MMetaType* NewL(const TAny* aMem, const TAny* aData);
   1.121 +
   1.122 +public:
   1.123 +	virtual TInt Load(TPtrC8& aBuffer);
   1.124 +	virtual TInt Store(TDes8& aBuffer) const;
   1.125 +    virtual void Copy(const TAny* aData);
   1.126 +	virtual TInt Length() const;
   1.127 +
   1.128 +protected:
   1.129 +    TMetaObjectPtr(const TAny* aData);
   1.130 +
   1.131 +private:
   1.132 +    TYPE** iData;
   1.133 +	};
   1.134 +
   1.135 +template<class TYPE>
   1.136 +class TMetaPtr : public MMetaType
   1.137 +/**
   1.138 +
   1.139 +Implementation of MMetaType for pointers to meta objects
   1.140 +
   1.141 +@internalComponent
   1.142 +@released since v9.0 */
   1.143 +	{
   1.144 +public:
   1.145 +    inline static MMetaType* NewL(const TAny* aMem, const TAny* aData);
   1.146 +
   1.147 +	virtual TInt Load(TPtrC8& aBuffer);
   1.148 +	virtual TInt Store(TDes8& aBuffer) const;
   1.149 +    virtual void Copy(const TAny* aData);
   1.150 +	virtual TInt Length() const;
   1.151 +
   1.152 +protected:
   1.153 +    TMetaPtr(const TAny* aData);
   1.154 +
   1.155 +private:
   1.156 +    TYPE** iData;
   1.157 +	};
   1.158 +
   1.159 +template<class TYPE>
   1.160 +MMetaType* TMeta<TYPE>::NewL(const TAny* aMem, const TAny* aData)
   1.161 +/**
   1.162 + * Instantiates a meta type of a particular type.
   1.163 + * Used for attribure registration (in the data v-table).
   1.164 + */
   1.165 +    {
   1.166 +    return ::new ((TUint8*)aMem) TMeta<TYPE>(aData);
   1.167 +    }
   1.168 +
   1.169 +template<class TYPE>
   1.170 +inline TMeta<TYPE>::TMeta(const TAny* aData)
   1.171 +:    iData((TYPE*)aData)
   1.172 +/**
   1.173 + * Constructor
   1.174 + */
   1.175 +    {
   1.176 +    __ASSERT_DEBUG(iData!=NULL,User::Panic(_L("TMetaType"),KErrArgument));
   1.177 +    }
   1.178 +
   1.179 +template<class TYPE>
   1.180 +TInt TMeta<TYPE>::Load(TPtrC8& aBuffer)
   1.181 +/**
   1.182 + * Loads content of a meta object (in iData) from a descriptor
   1.183 + */
   1.184 +    {
   1.185 +	TInt len = Length();
   1.186 +	if (aBuffer.Length() < len)
   1.187 +		{
   1.188 +		return KErrArgument;
   1.189 +		}
   1.190 +    Mem::Copy((TYPE*)iData,aBuffer.Ptr(),len);
   1.191 +	aBuffer.Set(aBuffer.Ptr()+len, aBuffer.Length()-len); //update pointer
   1.192 +	return KErrNone;
   1.193 +    }
   1.194 +
   1.195 +template<class TYPE>
   1.196 +TInt TMeta<TYPE>::Store(TDes8& aBuffer) const
   1.197 +/**
   1.198 + * Stores content of a meta object (in iData) to a descriptor
   1.199 + */
   1.200 +    {
   1.201 +	TInt len = Length();
   1.202 +	if (aBuffer.MaxLength() - aBuffer.Length() < len)
   1.203 +		{
   1.204 +		return KErrOverflow;
   1.205 +		}
   1.206 +	aBuffer.Append((TUint8*)iData, len);
   1.207 +	return KErrNone;
   1.208 +    }
   1.209 +
   1.210 +template<class TYPE>
   1.211 +void TMeta<TYPE>::Copy(const TAny* aData)
   1.212 +/**
   1.213 + * Copies content of a meta object (in aData) into another meta object (in iData).
   1.214 + * This is a MMetaType implementation for simple (T) types so it just copies the memory.
   1.215 + */
   1.216 +    {
   1.217 +    Mem::Copy((TAny*)iData,aData,Length());
   1.218 +    }
   1.219 +
   1.220 +template<class TYPE>
   1.221 +TInt TMeta<TYPE>::Length() const
   1.222 +/**
   1.223 + * Returns the length of the handled meta object.
   1.224 + */
   1.225 +    {
   1.226 +    return sizeof(TYPE);
   1.227 +    }
   1.228 +
   1.229 +template<class TYPE>
   1.230 +MMetaType* TMetaObject<TYPE>::NewL(const TAny* aMem, const TAny* aData)
   1.231 +/**
   1.232 + * Instantiates a meta type of a particular type.
   1.233 + * Used for attribure registration (in the data v-table).
   1.234 + */
   1.235 +    {
   1.236 +    return ::new ((TUint8*)aMem) TMetaObject<TYPE>(aData);
   1.237 +    }
   1.238 +
   1.239 +template<class TYPE>
   1.240 +inline TMetaObject<TYPE>::TMetaObject(const TAny* aData)
   1.241 +:    iData((TYPE*)aData)
   1.242 +/**
   1.243 + * Constructor
   1.244 + */
   1.245 +    {
   1.246 +    __ASSERT_DEBUG(iData!=NULL,User::Panic(_L("TMetaType"),KErrArgument));
   1.247 +    }
   1.248 +
   1.249 +template<class TYPE>
   1.250 +TInt TMetaObject<TYPE>::Load(TPtrC8& aBuffer)
   1.251 +/**
   1.252 + * Loads content of a meta object (in iData) from a descriptor
   1.253 + */
   1.254 +   {
   1.255 +	TInt err = iData->GetTypeId().Check( aBuffer );
   1.256 +	return err == KErrNone ? iData->Load(aBuffer) : err;
   1.257 +   }
   1.258 +
   1.259 +template<class TYPE>
   1.260 +TInt TMetaObject<TYPE>::Store(TDes8& aBuffer) const
   1.261 +/**
   1.262 + * Stores content of a meta object (in iData) to a descriptor
   1.263 + */
   1.264 +    {
   1.265 +	return iData->Store(aBuffer);
   1.266 +    }
   1.267 +
   1.268 +template<class TYPE>
   1.269 +void TMetaObject<TYPE>::Copy(const TAny* aData)
   1.270 +/**
   1.271 + * Copies content of a meta object (in aData) into another meta object (in iData).
   1.272 + */
   1.273 +    {
   1.274 +	iData->Copy(*((TYPE*)aData));
   1.275 +    }
   1.276 +
   1.277 +template<class TYPE>
   1.278 +TInt TMetaObject<TYPE>::Length() const
   1.279 +/**
   1.280 + * Returns the length of the handled meta object.
   1.281 + */
   1.282 +    {
   1.283 +	return iData->Length();
   1.284 +    }
   1.285 +
   1.286 +template<class TYPE>
   1.287 +MMetaType* TMetaObjectPtr<TYPE>::NewL(const TAny* aMem, const TAny* aData)
   1.288 +/**
   1.289 + * Instantiates a meta type of a particular type.
   1.290 + * Used for attribure registration (in the data v-table).
   1.291 + */
   1.292 +    {
   1.293 +    return ::new ((TUint8*)aMem) TMetaObjectPtr<TYPE>(aData);
   1.294 +    }
   1.295 +
   1.296 +template<class TYPE>
   1.297 +inline TMetaObjectPtr<TYPE>::TMetaObjectPtr(const TAny* aData)
   1.298 +:    iData((TYPE**)aData)
   1.299 +/**
   1.300 + * Constructor
   1.301 + */
   1.302 +    {
   1.303 +    __ASSERT_DEBUG(iData!=NULL,User::Panic(_L("TMetaType"),KErrArgument));
   1.304 +    __ASSERT_DEBUG(*iData!=NULL,User::Panic(_L("TMetaType"),KErrArgument));
   1.305 +    }
   1.306 +
   1.307 +template<class TYPE>
   1.308 +TInt TMetaObjectPtr<TYPE>::Load(TPtrC8& aBuffer)
   1.309 +/**
   1.310 + * Loads content of a meta object (in iData) from a descriptor
   1.311 + */
   1.312 +   {
   1.313 +	TInt err = (*iData)->GetTypeId().Check( aBuffer );
   1.314 +	return err == KErrNone ? (*iData)->Load(aBuffer) : err;
   1.315 +   }
   1.316 +
   1.317 +template<class TYPE>
   1.318 +TInt TMetaObjectPtr<TYPE>::Store(TDes8& aBuffer) const
   1.319 +/**
   1.320 + * Stores content of a meta object (in iData) to a descriptor
   1.321 + */
   1.322 +    {
   1.323 +	return (*iData)->Store(aBuffer);
   1.324 +    }
   1.325 +
   1.326 +template<class TYPE>
   1.327 +void TMetaObjectPtr<TYPE>::Copy(const TAny* aData)
   1.328 +/**
   1.329 + * Copies content of a meta object (in aData) into another meta object (in iData).
   1.330 + */
   1.331 +    {
   1.332 +	(*iData)->Copy(*((TYPE*)aData));
   1.333 +    }
   1.334 +
   1.335 +template<class TYPE>
   1.336 +TInt TMetaObjectPtr<TYPE>::Length() const
   1.337 +/**
   1.338 + * Returns the length of the handled meta object.
   1.339 + */
   1.340 +    {
   1.341 +	return (*iData)->Length();
   1.342 +    }
   1.343 +
   1.344 +template<class TYPE>
   1.345 +inline TMetaPtr<TYPE>::TMetaPtr(const TAny* aData)
   1.346 +:    iData((TYPE**)aData)
   1.347 +/**
   1.348 + * Constructor
   1.349 + */
   1.350 +    {
   1.351 +    }
   1.352 +
   1.353 +template<class TYPE>
   1.354 +MMetaType* TMetaPtr<TYPE>::NewL(const TAny* aMem, const TAny* aData)
   1.355 +/**
   1.356 + * Instantiates a meta type of a particular type.
   1.357 + * Used for attribure registration (in the data v-table).
   1.358 + */
   1.359 +    {
   1.360 +    return ::new ((TUint8*)aMem) TMetaPtr<TYPE>(aData);
   1.361 +    }
   1.362 +
   1.363 +template<class TYPE>
   1.364 +TInt TMetaPtr<TYPE>::Load(TPtrC8& aBuffer)
   1.365 +/**
   1.366 + * Loads content of a meta object (in iData) from a descriptor
   1.367 + */
   1.368 +    {
   1.369 +	if (aBuffer.Length() < (TInt) sizeof(TUint32))
   1.370 +		{
   1.371 +		return KErrArgument;
   1.372 +		}
   1.373 +
   1.374 +	// Check for a NULL pointer when stored (First four bytes == 0)
   1.375 +	if (*((TUint32*)aBuffer.Ptr()) == 0)
   1.376 +		{
   1.377 +		// The pointer was NULL when it was stored
   1.378 +		aBuffer.Set(aBuffer.Ptr() + sizeof(TUint32), aBuffer.Length() - sizeof(TUint32));
   1.379 +		if (*iData != NULL)
   1.380 +			{
   1.381 +			delete *iData;
   1.382 +			*iData = NULL;
   1.383 +			}
   1.384 +		return KErrNone;
   1.385 +		}
   1.386 +
   1.387 +	if (*iData == NULL)
   1.388 +		{
   1.389 +		TRAPD(ret, *iData = reinterpret_cast<TYPE*>(TYPE::LoadL(aBuffer)));
   1.390 +		return ret;
   1.391 +		}
   1.392 +	else
   1.393 +		{
   1.394 +		return (*iData)->Load(aBuffer);
   1.395 +		}
   1.396 +    }
   1.397 +
   1.398 +template<class TYPE>
   1.399 +TInt TMetaPtr<TYPE>::Store(TDes8& aBuffer) const
   1.400 +/**
   1.401 + * Stores content of a meta object (in iData) to a descriptor
   1.402 + */
   1.403 +    {
   1.404 +	if (*iData == NULL)
   1.405 +		{
   1.406 +		const TUint32 KNullInt = 0;
   1.407 +		aBuffer.Append((TUint8*)&KNullInt, sizeof(TUint32));
   1.408 +		return KErrNone;
   1.409 +		}
   1.410 +	else
   1.411 +		{
   1.412 +		return (*iData)->Store(aBuffer);
   1.413 +		}
   1.414 +    }
   1.415 +
   1.416 +template<class TYPE>
   1.417 +void TMetaPtr<TYPE>::Copy(const TAny* aData)
   1.418 +/**
   1.419 + * Copies content of a meta object (in aData) into another meta object (in iData).
   1.420 + */
   1.421 +    {
   1.422 +	(*iData)->Copy(*((TYPE*)aData));
   1.423 +    }
   1.424 +
   1.425 +template<class TYPE>
   1.426 +TInt TMetaPtr<TYPE>::Length() const
   1.427 +/**
   1.428 + * Returns the length of the handled meta object.
   1.429 + */
   1.430 +    {
   1.431 +	if (*iData == NULL)
   1.432 +		{
   1.433 +		// Add length of null word (Used to represent a NULL pointer)
   1.434 +		return sizeof(TUint32);
   1.435 +		}
   1.436 +	else
   1.437 +		{
   1.438 +		return (*iData)->Length();
   1.439 +		}
   1.440 +    }
   1.441 +
   1.442 +} //namespace Meta
   1.443 +
   1.444 +
   1.445 +#endif //METATYPE_H