williamr@2: // Copyright (c) 2001-2009 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:  @file CHeaderCodec.h
williamr@2:  @warning : This file contains Rose Model ID comments - please do not delete
williamr@2: */
williamr@2: 
williamr@2: #ifndef __CHEADERCODEC_H__
williamr@2: #define __CHEADERCODEC_H__
williamr@2: 
williamr@2: // System includes
williamr@2: #include <e32base.h>
williamr@2: #include <http/framework/rheaderfield.h>
williamr@2: 
williamr@2: // Forward declarations
williamr@2: class CHeaderWriter;
williamr@2: class CHeaderReader;
williamr@2: 
williamr@2: 
williamr@2: //##ModelId=3C4C18850126
williamr@2: class CHeaderCodec : public CBase
williamr@2: /**
williamr@2: An abstract HTTP header codec.  
williamr@2: 
williamr@2: Each instance of a concrete subclass of CHeaderCodec is associated with, and owned
williamr@2: by, a specific	CProtocolHandler.  It provides on-demand encoding/decoding of
williamr@2: HTTP header data, between the generic format used by clients/filters to formulate
williamr@2: requests and interpret responses, and the raw format used by
williamr@2: the transport handlers (and origin servers/gateways/etc.)
williamr@2: 
williamr@2: The CHeaderCodec has an associated instance of a sub-class of each of
williamr@2: CHeaderReader and CHeaderWriter.  It delegates the actual encoding and
williamr@2: decoding function to these instances.
williamr@2: 
williamr@2: Header codecs provide a mechanism for extensibility whereby if one codec can't
williamr@2: decode (or encode) a given header, it locates a codec that can, and then delegates
williamr@2: the task to that codec instead.
williamr@2: @publishedAll
williamr@2: @released
williamr@2: */
williamr@2: 	{
williamr@2: public: // methods
williamr@2: 
williamr@2: /** 
williamr@2: 	Intended Usage:	Destructor - cleans up and releases resources to the system.
williamr@2: */
williamr@2: 	//##ModelId=3C4C18850194
williamr@2: 	IMPORT_C virtual ~CHeaderCodec();
williamr@2: 
williamr@2: /**
williamr@2: 	Encode the supplied header field.  This method uses the associated
williamr@2: 	concrete CHeaderWriter object to do a conversion of the field into
williamr@2: 	raw form from the generic internal representation.
williamr@2: 
williamr@2: 	@param aHeader (in) A proxy for the header field to be encoded
williamr@2: 	@leave KErrNotSupported if a codec that supports encoding this header
williamr@2: 		   cannot be found
williamr@2: */
williamr@2: 	//##ModelId=3C4C1885018C
williamr@2: 	IMPORT_C void EncodeHeaderL(RHeaderField& aHeader) const;
williamr@2: 
williamr@2: /**
williamr@2: 	Decode the supplied header field.  This method uses the associated
williamr@2: 	concrete CHeaderReader object to do a conversion of the field into
williamr@2: 	the generic internal representation from the raw form.
williamr@2: 
williamr@2: 	@param aHeader (in) A proxy for the header field to be decoded
williamr@2: 	
williamr@2: 	@leave KErrNotSupported if a codec that supports decoding this header
williamr@2:    		   cannot be found
williamr@2: 
williamr@2: */
williamr@2: 	//##ModelId=3C4C1885018A
williamr@2: 	IMPORT_C void DecodeHeaderL(RHeaderField& aHeader) const;
williamr@2: 
williamr@2: /**
williamr@2: 	Intended Usage: Concrete header codec classes must implement this method to
williamr@2: 	indicate to the framework whether their concrete CHeaderWriter is
williamr@2: 	capable of encoding the named header field.
williamr@2: 	@param aHeaderField	(in) A proxy for the header field to be encoded
williamr@2: 	@return A flag indicating ETrue if the field can be encoded.
williamr@2: */
williamr@2: 	//##ModelId=3C4C18850181
williamr@2: 	virtual TBool CanEncode(RStringF aHeaderField) const = 0;
williamr@2: 
williamr@2: /**
williamr@2: 	Intended Usage: Concrete header codec classes must implement this method to
williamr@2: 					indicate to the framework whether their concrete CHeaderReader is
williamr@2: 					capable of decoding the named header field.
williamr@2: 	@param			aHeaderField		(in) A proxy for the header field to be encoded
williamr@2: 	@return			A flag indicating ETrue if the field can be decoded.
williamr@2:  */
williamr@2: 	//##ModelId=3C4C18850178
williamr@2: 	virtual TBool CanDecode(RStringF aHeaderField) const = 0;
williamr@2: 
williamr@2: /**
williamr@2: 	Intended Usage: Concrete header codecs must be implement this method if they wish to
williamr@2: 					delegate the encoding/decoding of particular header fields to a
williamr@2: 					different codec.  
williamr@2: 					This would be done if the codec doesn't have the ability itself to
williamr@2: 					do the encode/decode but can locate an alternative that does. This 
williamr@2: 					function may leave with a Standard Symbian OS error code. eg. KErrNoMemory
williamr@2: 
williamr@2: 					The caller takes ownership of the returned codec.
williamr@2: 	@param aHeaderField (in) A proxy for the header field to be encoded
williamr@2: 	@return A pointer to the new CHeaderCodec, or NULL if one couldn't be found.
williamr@2: 	@leave KErrNoMemory, Not enough memory to create object.	
williamr@2: */
williamr@2: 	//##ModelId=3C4C18850176
williamr@2: 	virtual CHeaderCodec* FindDelegateCodecL(RStringF aHeaderField) const = 0;
williamr@2: 
williamr@2: protected: // methods
williamr@2: 
williamr@2: /**
williamr@2: 	Default constructor.
williamr@2:  */
williamr@2: 	//##ModelId=3A914DF20273
williamr@2: 	IMPORT_C CHeaderCodec();
williamr@2: 
williamr@2: /**
williamr@2: 	Second phase construction in which any necessary allocation is done
williamr@2: 	Implementations of this interface may leave with standard erros like KErrNoMemory if there is
williamr@2: 	insufficient memory for allocation in the second phase.
williamr@2:  */
williamr@2: 	//##ModelId=3C4C1885016E
williamr@2: 	IMPORT_C void ConstructL();
williamr@2: 
williamr@2: protected: // attributes
williamr@2: 
williamr@2: 	/** The owned header writer object that does actual encoding of header fields.
williamr@2: 	*/
williamr@2: 	//##ModelId=3C4C18850164
williamr@2: 	CHeaderWriter* iWriter;
williamr@2: 
williamr@2: 	/** The owned header reader object that does actual decoding of header fields.
williamr@2: 	*/
williamr@2: 	//##ModelId=3C4C1885015A
williamr@2: 	CHeaderReader* iReader;
williamr@2: 
williamr@2: private: // methods
williamr@2: 
williamr@2: /**	
williamr@2: 	Intended Usage:	Reserve a slot in the v-table to preserve future BC
williamr@2:  */
williamr@2: 	//##ModelId=3C4C1885016D
williamr@2: 	inline virtual void Reserved1();
williamr@2: 
williamr@2: /**	
williamr@2: 	Intended Usage:	Reserve a slot in the v-table to preserve future BC
williamr@2:  */
williamr@2: 	//##ModelId=3C4C1885016C
williamr@2: 	inline virtual void Reserved2();
williamr@2: 
williamr@2: private: // attributes
williamr@2: 
williamr@2: 	/** The most recently-obtained delegate codec
williamr@2: 	*/
williamr@2: 	//##ModelId=3C4C18850150
williamr@2: 	mutable CHeaderCodec* iDelegateCodec;
williamr@2: 	};
williamr@2: 
williamr@2: 
williamr@2: //##ModelId=3C4C188601D1
williamr@2: class CHeaderWriter : public CBase
williamr@2: /**
williamr@2: An abstract HTTP header encoder.  CHeaderWriter provides an interface used by its
williamr@2: owning codec to do conversion of header data from the generic internal header
williamr@2: representation to the raw representation used for a particular protocol/transport.
williamr@2: Specific sub-classes of CHeaderWriter are associated with specific protocol handlers.
williamr@2: @publishedAll
williamr@2: @released
williamr@2: */
williamr@2: 	{
williamr@2: public: // methods
williamr@2: 
williamr@2: /** 
williamr@2: 	Intended Usage:	Destructor - cleans up and release resources to the system.
williamr@2: */
williamr@2: 	//##ModelId=3C4C188601FC
williamr@2: 	IMPORT_C virtual ~CHeaderWriter();
williamr@2: 
williamr@2: /**
williamr@2: 	Intended Usage:	Encodes the supplied header field.  This method does a conversion
williamr@2: 					of the field into raw form from the generic internal representation.
williamr@2: 
williamr@2: 					Implementations of this interface may leave with any of KErrNotSupported, KErrHttpEncodeDoWWWAuthenticate,
williamr@2: 					KErrHttpEncodeAuthorization, KErrHttpEncodeDoAge, KErrHttpEncodeDoVary, KErrHttpEncodeDoContentLanguage.
williamr@2: 
williamr@2: 					Specific header writer sub-classes must implement this method.
williamr@2: 	@param			aHeader		(in) A proxy for the header field to be encoded
williamr@2:  */
williamr@2: 	//##ModelId=3C4C188601FA
williamr@2: 	virtual void EncodeHeaderL(RHeaderField& aHeader) = 0;
williamr@2: 
williamr@2: protected: // methods
williamr@2: 
williamr@2: /**
williamr@2: 	Default constructor.
williamr@2:  */
williamr@2: 	IMPORT_C CHeaderWriter();
williamr@2: 
williamr@2: /**
williamr@2: 	Second phase construction in which any necessary allocation is done
williamr@2: 	Implementations of this interface may leave with standard errors like KErrNoMemory.
williamr@2:  */
williamr@2: 	//##ModelId=3C4C188601F9
williamr@2: 	IMPORT_C void ConstructL();
williamr@2: 
williamr@2: private: // methods
williamr@2: 
williamr@2: /**	
williamr@2: 	Intended Usage:	Reserve a slot in the v-table to preserve future BC
williamr@2:  */
williamr@2: 	//##ModelId=3C4C188601F1
williamr@2: 	inline virtual void Reserved1();
williamr@2: 
williamr@2: /**	
williamr@2: 	Intended Usage:	Reserve a slot in the v-table to preserve future BC
williamr@2:  */
williamr@2: 	//##ModelId=3C4C188601F0
williamr@2: 	inline virtual void Reserved2();
williamr@2: 	};
williamr@2: 
williamr@2: 
williamr@2: //##ModelId=3C4C188602FE
williamr@2: class CHeaderReader : public CBase
williamr@2: /**
williamr@2: An abstract HTTP header decoder.  CHeaderReader provides an interface used by its
williamr@2: owning codec to do conversion of header data from the raw representation used for
williamr@2: a particular protocol/transport to the generic internal header representation.
williamr@2: Specific sub-classes of CHeaderWriter are associated with specific protocol
williamr@2: handlers.
williamr@2: @publishedAll
williamr@2: @released
williamr@2: */
williamr@2: 	{
williamr@2: public: // methods
williamr@2: 
williamr@2: /** 
williamr@2: 	Intended Usage:	Destructor - cleans up and release resources to the system.
williamr@2: */
williamr@2: 	//##ModelId=3C4C1886031E
williamr@2: 	IMPORT_C virtual ~CHeaderReader();
williamr@2: 
williamr@2: /**
williamr@2: 	Intended Usage:	Decodes the supplied header field.  This method does a conversion
williamr@2: 	of the field from the generic internal representation into raw form.
williamr@2: 
williamr@2: 	Specific header reader sub-classes must implement this method.
williamr@2: 
williamr@2: 	Implementations of this interface may leave with any of KErrHttpDecodeAccept, KErrHttpDecodeAcceptCharset, 
williamr@2: 	KErrHttpDecodeAcceptLanguage, KErrHttpDecodeAcceptEncoding, KErrNotSupported.
williamr@2: 
williamr@2: 	@param aHeader (in) A proxy for the header field to be decoded
williamr@2: 	
williamr@2: */
williamr@2: 	//##ModelId=3C4C1886031C
williamr@2: 	virtual void DecodeHeaderL(RHeaderField& aHeader) = 0;
williamr@2: 
williamr@2: protected: // methods
williamr@2: 
williamr@2: /**
williamr@2: 	Default constructor.
williamr@2:  */
williamr@2: 	IMPORT_C CHeaderReader();
williamr@2: 
williamr@2: /**
williamr@2: 	Second phase construction in which any necessary allocation is done
williamr@2: 	Implementations of this interface may leave with standard errors like KErrNoMemory.
williamr@2:  */
williamr@2: 	//##ModelId=3C4C18860315
williamr@2: 	IMPORT_C void ConstructL();
williamr@2: 
williamr@2: private: // methods
williamr@2: 
williamr@2: /**	
williamr@2: 	Intended Usage:	Reserve a slot in the v-table to preserve future BC
williamr@2:  */
williamr@2: 	//##ModelId=3C4C18860314
williamr@2: 	inline virtual void Reserved1();
williamr@2: 
williamr@2: /**	
williamr@2: 	Intended Usage:	Reserve a slot in the v-table to preserve future BC
williamr@2:  */
williamr@2: 	//##ModelId=3C4C18860313
williamr@2: 	inline virtual void Reserved2();
williamr@2: 	};
williamr@2: 
williamr@2: 
williamr@2: inline void CHeaderCodec::Reserved1()
williamr@2: 	{}
williamr@2: inline void CHeaderCodec::Reserved2()
williamr@2: 	{}
williamr@2: inline void CHeaderWriter::Reserved1()
williamr@2: 	{}
williamr@2: inline void CHeaderWriter::Reserved2()
williamr@2: 	{}
williamr@2: inline void CHeaderReader::Reserved1()
williamr@2: 	{}
williamr@2: inline void CHeaderReader::Reserved2()
williamr@2: 	{}
williamr@2: 
williamr@2: #endif /* __CHEADERCODEC_H__ */