/*

 * Licensed to the Apache Software Foundation (ASF) under one or more

 * contributor license agreements.  See the NOTICE file distributed with

 * this work for additional information regarding copyright ownership.

 * The ASF licenses this file to You under the Apache License, Version 2.0

 * (the "License"); you may not use this file except in compliance with

 * the License.  You may obtain a copy of the License at

 * 

 *      http://www.apache.org/licenses/LICENSE-2.0

 * 

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

/*

 * $Id: Base64.hpp 568078 2007-08-21 11:43:25Z amassari $

 */

#ifndef BASE64_HPP

#define BASE64_HPP

#include <xercesc/util/XercesDefs.hpp>

#include <xercesc/util/XMLUniDefs.hpp>

#include <xercesc/framework/MemoryManager.hpp>

XERCES_CPP_NAMESPACE_BEGIN

//

// This class provides encode/decode for RFC 2045 Base64 as

// defined by RFC 2045, N. Freed and N. Borenstein.

// RFC 2045: Multipurpose Internet Mail Extensions (MIME)

// Part One: Format of Internet Message Bodies. Reference

// 1996 Available at: http://www.ietf.org/rfc/rfc2045.txt

// This class is used by XML Schema binary format validation

//

//

class XMLUTIL_EXPORT Base64

{

public :

    enum Conformance

    {

        Conf_RFC2045

      , Conf_Schema

    };

    //@{

    /**

     * Encodes octets into Base64 data

     *

     * NOTE: The returned buffer is dynamically allocated and is the

     * responsibility of the caller to delete it when not longer needed.

     * You can call XMLString::release to release this returned buffer.

     *

     * If a memory manager is provided, ask the memory manager to de-allocate

     * the returned buffer.

     *

     * @param inputData Binary data in XMLByte stream.

     * @param inputLength Length of the XMLByte stream.

     * @param outputLength Length of the encoded Base64 byte stream.

     * @param memMgr client provided memory manager

     * @return Encoded Base64 data in XMLByte stream,

     *      or NULL if input data can not be encoded.

     * @see   XMLString::release(XMLByte**)

     */

    static XMLByte* encode(const XMLByte* const inputData

                         , const unsigned int   inputLength

                         , unsigned int*        outputLength

                         , MemoryManager* const memMgr = 0);

    /**

     * Decodes Base64 data into octets

     *

     * NOTE: The returned buffer is dynamically allocated and is the

     * responsibility of the caller to delete it when not longer needed.

     * You can call XMLString::release to release this returned buffer.

     *

     * If a memory manager is provided, ask the memory manager to de-allocate

     * the returned buffer.

     *

     * @param inputData Base64 data in XMLByte stream.

     * @param decodedLength Length of decoded XMLByte stream.

     * @param memMgr client provided memory manager

     * @param conform conformance specified: if the input data conforms to the

     *                RFC 2045 it is allowed to have any number of whitespace

     *                characters inside; if it conforms to the XMLSchema specs,

     *                it is allowed to have at most one whitespace character

     *                between the quartets

     * @return Decoded binary data in XMLByte stream,

     *      or NULL if input data can not be decoded.

     * @see   XMLString::release(XMLByte**)

     */

    static XMLByte* decode(

                           const XMLByte*        const   inputData

                         ,       unsigned int*           decodedLength

                         ,       MemoryManager*  const   memMgr = 0

                         ,       Conformance             conform = Conf_RFC2045

                          );

    /**

     * Decodes Base64 data into XMLCh

     *

     * NOTE: The returned buffer is dynamically allocated and is the

     * responsibility of the caller to delete it when not longer needed.

     * You can call XMLString::release to release this returned buffer.

     *

     * If a memory manager is provided, ask the memory manager to de-allocate

     * the returned buffer.

     *

     * @param inputData Base64 data in XMLCh stream.

     * @param decodedLength Length of decoded XMLCh stream

     * @param memMgr client provided memory manager

     * @param conform conformance specified: if the input data conforms to the

     *                RFC 2045 it is allowed to have any number of whitespace

     *                characters inside; if it conforms to the XMLSchema specs,

     *                it is allowed to have at most one whitespace character

     *                between the quartets

     * @return Decoded binary data in XMLCh stream,

     *      or NULL if input data can not be decoded.

     * @see   XMLString::release(XMLCh**)

     * @deprecated use decodeToXMLByte instead.

     */

    static XMLCh* decode(

                         const XMLCh*          const    inputData

                       ,       unsigned int*            decodedLength

                       ,       MemoryManager*  const    memMgr = 0

                       ,       Conformance              conform = Conf_RFC2045

                        );

   /**

     * Decodes Base64 data into octets

     *

     * NOTE: The returned buffer is dynamically allocated and is the

     * responsibility of the caller to delete it when not longer needed.

     * You can call XMLString::release to release this returned buffer.

     *

     * If a memory manager is provided, ask the memory manager to de-allocate

     * the returned buffer.

     *

     * @param inputData Base64 data in XMLCh stream.

     * @param decodedLength Length of decoded XMLByte stream.

     * @param memMgr client provided memory manager

     * @param conform conformance specified: if the input data conforms to the

     *                RFC 2045 it is allowed to have any number of whitespace

     *                characters inside; if it conforms to the XMLSchema specs,

     *                it is allowed to have at most one whitespace character

     *                between the quartets

     * @return Decoded binary data in XMLByte stream,

     *      or NULL if input data can not be decoded.

     * @see   XMLString::release(XMLByte**)

     */

    static XMLByte* decodeToXMLByte(

                           const XMLCh*          const   inputData

                         ,       unsigned int*           decodedLength

                         ,       MemoryManager*  const   memMgr = 0

                         ,       Conformance             conform = Conf_RFC2045

                          );

    /**

     * Get data length

	 *

     * Returns length of decoded data given an array

     * containing encoded data.

     *

     * @param inputData Base64 data in XMLCh stream.

     * @param memMgr client provided memory manager

     * @param conform conformance specified

     * @return Length of decoded data,

	 *      or -1 if input data can not be decoded.

     */

    static int getDataLength(

                             const XMLCh*         const  inputData

                            ,      MemoryManager* const  memMgr = 0

                            ,      Conformance           conform = Conf_RFC2045

                             );

    //@}

     /**

     * get canonical representation

     *

     * Caller is responsible for the proper deallcation

     * of the string returned.

     * 

     * @param inputData A string containing the Base64

     * @param memMgr client provided memory manager

     * @param conform conformance specified

     *

     * return: the canonical representation of the Base64

     *         if it is a valid Base64

     *         0 otherwise

     */

    static XMLCh* getCanonicalRepresentation

                  (

                      const XMLCh*          const inputData

                    ,       MemoryManager*  const memMgr = 0

                    ,       Conformance           conform = Conf_RFC2045

                  );

private :

    // -----------------------------------------------------------------------

    //  Helper methods

    // -----------------------------------------------------------------------

    static XMLByte* decode(

                           const XMLByte*        const   inputData

                         ,       unsigned int*           outputLength

                         ,       XMLByte*&               canRepData

                         ,       MemoryManager*  const   memMgr = 0

                         ,       Conformance             conform = Conf_RFC2045

                          );

    static void init();

    static bool isData(const XMLByte& octet);

    static bool isPad(const XMLByte& octet);

    static XMLByte set1stOctet(const XMLByte&, const XMLByte&);

    static XMLByte set2ndOctet(const XMLByte&, const XMLByte&);

    static XMLByte set3rdOctet(const XMLByte&, const XMLByte&);

    static void split1stOctet(const XMLByte&, XMLByte&, XMLByte&);

    static void split2ndOctet(const XMLByte&, XMLByte&, XMLByte&);

    static void split3rdOctet(const XMLByte&, XMLByte&, XMLByte&);

    // -----------------------------------------------------------------------

    //  Unimplemented constructors and operators

    // -----------------------------------------------------------------------

    Base64();

    Base64(const Base64&);

    // -----------------------------------------------------------------------

    //  Private data members

    //

    //  base64Alphabet

    //     The Base64 alphabet (see RFC 2045).

    //

    //  base64Padding

    //     Padding character (see RFC 2045).

    //

    //  base64Inverse

    //     Table used in decoding base64.

    //

    //  isInitialized

    //     Set once base64Inverse is initalized.

    //

    //  quadsPerLine

    //     Number of quadruplets per one line. The encoded output

    //     stream must be represented in lines of no more

    //     than 19 quadruplets each.

    //

    // -----------------------------------------------------------------------

    static const XMLByte  base64Alphabet[];

    static const XMLByte  base64Padding;

    static XMLByte  base64Inverse[];

    static bool  isInitialized;

    static const unsigned int  quadsPerLine;

};

// -----------------------------------------------------------------------

//  Helper methods

// -----------------------------------------------------------------------

inline bool Base64::isPad(const XMLByte& octet)

{

    return ( octet == base64Padding );

}

inline XMLByte Base64::set1stOctet(const XMLByte& b1, const XMLByte& b2)

{

    return (( b1 << 2 ) | ( b2 >> 4 ));

}

inline XMLByte Base64::set2ndOctet(const XMLByte& b2, const XMLByte& b3)

{

    return (( b2 << 4 ) | ( b3 >> 2 ));

}

inline XMLByte Base64::set3rdOctet(const XMLByte& b3, const XMLByte& b4)

{

    return (( b3 << 6 ) | b4 );

}

inline void Base64::split1stOctet(const XMLByte& ch, XMLByte& b1, XMLByte& b2) {

    b1 = ch >> 2;

    b2 = ( ch & 0x3 ) << 4;

}

inline void Base64::split2ndOctet(const XMLByte& ch, XMLByte& b2, XMLByte& b3) {

    b2 |= ch >> 4;  // combine with previous value

    b3 = ( ch & 0xf ) << 2;

}

inline void Base64::split3rdOctet(const XMLByte& ch, XMLByte& b3, XMLByte& b4) {

    b3 |= ch >> 6;  // combine with previous value

    b4 = ( ch & 0x3f );

}

XERCES_CPP_NAMESPACE_END

#endif