/*
* 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.
*/
// ---------------------------------------------------------------------------
// Includes
// ---------------------------------------------------------------------------
#include <xercesc/util/BitOps.hpp>
#include <xercesc/util/XMLUCS4Transcoder.hpp>
#include <xercesc/util/TranscodingException.hpp>
#include <string.h>
XERCES_CPP_NAMESPACE_BEGIN
// ---------------------------------------------------------------------------
// XMLUCS4Transcoder: Constructors and Destructor
// ---------------------------------------------------------------------------
XMLUCS4Transcoder::XMLUCS4Transcoder(const XMLCh* const encodingName
, const XMLSize_t blockSize
, const bool swapped
, MemoryManager* const manager) :
XMLTranscoder(encodingName, blockSize, manager)
, fSwapped(swapped)
{
}
XMLUCS4Transcoder::~XMLUCS4Transcoder()
{
}
// ---------------------------------------------------------------------------
// XMLUCS4Transcoder: Implementation of the transcoder API
// ---------------------------------------------------------------------------
XMLSize_t
XMLUCS4Transcoder::transcodeFrom(const XMLByte* const srcData
, const XMLSize_t srcCount
, XMLCh* const toFill
, const XMLSize_t maxChars
, XMLSize_t& bytesEaten
, unsigned char* const charSizes)
{
//
// Get pointers to the start and end of the source buffer in terms of
// UCS-4 characters.
//
const UCS4Ch* srcPtr = (const UCS4Ch*)srcData;
const UCS4Ch* srcEnd = srcPtr + (srcCount / sizeof(UCS4Ch));
//
// Get pointers to the start and end of the target buffer, which is
// in terms of the XMLCh chars we output.
//
XMLCh* outPtr = toFill;
XMLCh* outEnd = toFill + maxChars;
//
// And get a pointer into the char sizes buffer. We will run this
// up as we put chars into the output buffer.
//
unsigned char* sizePtr = charSizes;
//
// Now process chars until we either use up all our source or all of
// our output space.
//
while ((outPtr < outEnd) && (srcPtr < srcEnd))
{
//
// Get the next UCS char out of the buffer. Don't bump the ptr
// yet since we might not have enough storage for it in the target
// (if its causes a surrogate pair to be created.
//
UCS4Ch nextVal = *srcPtr;
// If it needs to be swapped, then do it
if (fSwapped)
nextVal = BitOps::swapBytes(nextVal);
// Handle a surrogate pair if needed
if (nextVal & 0xFFFF0000)
{
//
// If we don't have room for both of the chars, then we
// bail out now.
//
if (outPtr + 1 == outEnd)
break;
const XMLInt32 LEAD_OFFSET = 0xD800 - (0x10000 >> 10);
const XMLCh ch1 = XMLCh(LEAD_OFFSET + (nextVal >> 10));
const XMLCh ch2 = XMLCh(0xDC00 + (nextVal & 0x3FF));
//
// We have room so store them both. But note that the
// second one took up no source bytes!
//
*sizePtr++ = sizeof(UCS4Ch);
*outPtr++ = ch1;
*sizePtr++ = 0;
*outPtr++ = ch2;
}
else
{
//
// No surrogate, so just store it and bump the count of chars
// read. Update the char sizes buffer for this char's entry.
//
*sizePtr++ = sizeof(UCS4Ch);
*outPtr++ = XMLCh(nextVal);
}
// Indicate that we ate another UCS char's worth of bytes
srcPtr++;
}
// Set the bytes eaten parameter
bytesEaten = ((const XMLByte*)srcPtr) - srcData;
// And return the chars written into the output buffer
return outPtr - toFill;
}
XMLSize_t
XMLUCS4Transcoder::transcodeTo( const XMLCh* const srcData
, const XMLSize_t srcCount
, XMLByte* const toFill
, const XMLSize_t maxBytes
, XMLSize_t& charsEaten
, const UnRepOpts)
{
//
// Get pointers to the start and end of the source buffer, which
// is in terms of XMLCh chars.
//
const XMLCh* srcPtr = srcData;
const XMLCh* srcEnd = srcData + srcCount;
//
// Get pointers to the start and end of the target buffer, in terms
// of UCS-4 chars.
//
UCS4Ch* outPtr = (UCS4Ch*)toFill;
UCS4Ch* outEnd = outPtr + (maxBytes / sizeof(UCS4Ch));
//
// Now loop until we either run out of source characters or we
// fill up our output buffer.
//
XMLCh trailCh;
while ((outPtr < outEnd) && (srcPtr < srcEnd))
{
//
// Get out an XMLCh char from the source. Don't bump up the
// pointer yet, since it might be a leading for which we don't
// have the trailing.
//
const XMLCh curCh = *srcPtr;
//
// If its a leading char of a surrogate pair handle it one way,
// else just cast it over into the target.
//
if ((curCh >= 0xD800) && (curCh <= 0xDBFF))
{
//
// Ok, we have to have another source char available or we
// just give up without eating the leading char.
//
if (srcPtr + 1 == srcEnd)
break;
//
// We have the trailing char, so eat the first char and the
// trailing char from the source.
//
srcPtr++;
trailCh = *srcPtr++;
//
// Then make sure its a legal trailing char. If not, throw
// an exception.
//
if ( !( (trailCh >= 0xDC00) && (trailCh <= 0xDFFF) ) )
ThrowXMLwithMemMgr(TranscodingException, XMLExcepts::Trans_BadTrailingSurrogate, getMemoryManager());
// And now combine the two into a single output char
const XMLInt32 SURROGATE_OFFSET = 0x10000 - (0xD800 << 10) - 0xDC00;
*outPtr++ = (curCh << 10) + trailCh + SURROGATE_OFFSET;
}
else
{
//
// Its just a char, so we can take it as is. If we need to
// swap it, then swap it. Because of flakey compilers, use
// a temp first.
//
const UCS4Ch tmpCh = UCS4Ch(curCh);
if (fSwapped)
*outPtr++ = BitOps::swapBytes(tmpCh);
else
*outPtr++ = tmpCh;
// Bump the source pointer
srcPtr++;
}
}
// Set the chars we ate from the source
charsEaten = srcPtr - srcData;
// Return the bytes we wrote to the output
return ((XMLByte*)outPtr) - toFill;
}
bool XMLUCS4Transcoder::canTranscodeTo(const unsigned int)
{
// We can handle anything
return true;
}
XERCES_CPP_NAMESPACE_END