/*
* 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.
*/
/**
* $Id$
*/
// ---------------------------------------------------------------------------
// Includes
// ---------------------------------------------------------------------------
#include <xercesc/util/TranscodingException.hpp>
#include <xercesc/util/XMLString.hpp>
#include <xercesc/util/XMLUniDefs.hpp>
#include <xercesc/util/XMLUTF8Transcoder.hpp>
XERCES_CPP_NAMESPACE_BEGIN
// ---------------------------------------------------------------------------
// Local static data
//
// gUTFBytes
// A list of counts of trailing bytes for each initial byte in the input.
//
// gUTFByteIndicator
// For a UTF8 sequence of n bytes, n>=2, the first byte of the
// sequence must contain n 1's followed by precisely 1 0 with the
// rest of the byte containing arbitrary bits. This array stores
// the required bit pattern for validity checking.
// gUTFByteIndicatorTest
// When bitwise and'd with the observed value, if the observed
// value is correct then a result matching gUTFByteIndicator will
// be produced.
//
// gUTFOffsets
// A list of values to offset each result char type, according to how
// many source bytes when into making it.
//
// gFirstByteMark
// A list of values to mask onto the first byte of an encoded sequence,
// indexed by the number of bytes used to create the sequence.
// ---------------------------------------------------------------------------
static const XMLByte gUTFBytes[256] =
{
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1
, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2
, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5
};
static const XMLByte gUTFByteIndicator[6] =
{
0x00, 0xC0, 0xE0, 0xF0, 0xF8, 0xFC
};
static const XMLByte gUTFByteIndicatorTest[6] =
{
0x80, 0xE0, 0xF0, 0xF8, 0xFC, 0xFE
};
static const XMLUInt32 gUTFOffsets[6] =
{
0, 0x3080, 0xE2080, 0x3C82080, 0xFA082080, 0x82082080
};
static const XMLByte gFirstByteMark[7] =
{
0x00, 0x00, 0xC0, 0xE0, 0xF0, 0xF8, 0xFC
};
// ---------------------------------------------------------------------------
// XMLUTF8Transcoder: Constructors and Destructor
// ---------------------------------------------------------------------------
XMLUTF8Transcoder::XMLUTF8Transcoder(const XMLCh* const encodingName
, const XMLSize_t blockSize
, MemoryManager* const manager)
:XMLTranscoder(encodingName, blockSize, manager)
{
}
XMLUTF8Transcoder::~XMLUTF8Transcoder()
{
}
// ---------------------------------------------------------------------------
// XMLUTF8Transcoder: Implementation of the transcoder API
// ---------------------------------------------------------------------------
XMLSize_t
XMLUTF8Transcoder::transcodeFrom(const XMLByte* const srcData
, const XMLSize_t srcCount
, XMLCh* const toFill
, const XMLSize_t maxChars
, XMLSize_t& bytesEaten
, unsigned char* const charSizes)
{
// Watch for pathological scenario. Shouldn't happen, but...
if (!srcCount || !maxChars)
return 0;
//
// Get pointers to our start and end points of the input and output
// buffers.
//
const XMLByte* srcPtr = srcData;
const XMLByte* srcEnd = srcPtr + srcCount;
XMLCh* outPtr = toFill;
XMLCh* outEnd = outPtr + maxChars;
unsigned char* sizePtr = charSizes;
//
// We now loop until we either run out of input data, or room to store
// output chars.
//
while ((srcPtr < srcEnd) && (outPtr < outEnd))
{
// Special-case ASCII, which is a leading byte value of <= 127
if (*srcPtr <= 127)
{
// Handle ASCII in groups instead of single character at a time.
const XMLByte* srcPtr_save = srcPtr;
const XMLSize_t chunkSize = (srcEnd-srcPtr)<(outEnd-outPtr)?(srcEnd-srcPtr):(outEnd-outPtr);
for(XMLSize_t i=0;i<chunkSize && *srcPtr <= 127;++i)
*outPtr++ = XMLCh(*srcPtr++);
memset(sizePtr,1,srcPtr - srcPtr_save);
sizePtr += srcPtr - srcPtr_save;
if (srcPtr == srcEnd || outPtr == outEnd)
break;
}
// See how many trailing src bytes this sequence is going to require
const unsigned int trailingBytes = gUTFBytes[*srcPtr];
//
// If there are not enough source bytes to do this one, then we
// are done. Note that we done >= here because we are implicitly
// counting the 1 byte we get no matter what.
//
// If we break out here, then there is nothing to undo since we
// haven't updated any pointers yet.
//
if (srcPtr + trailingBytes >= srcEnd)
break;
// Looks ok, so lets build up the value
// or at least let's try to do so--remembering that
// we cannot assume the encoding to be valid:
// first, test first byte
if((gUTFByteIndicatorTest[trailingBytes] & *srcPtr) != gUTFByteIndicator[trailingBytes]) {
char pos[2] = {(char)0x31, 0};
char len[2] = {(char)(trailingBytes+0x31), 0};
char byte[2] = {*srcPtr,0};
ThrowXMLwithMemMgr3(UTFDataFormatException, XMLExcepts::UTF8_FormatError, pos, byte, len, getMemoryManager());
}
/***
* http://www.unicode.org/reports/tr27/
*
* Table 3.1B. lists all of the byte sequences that are legal in UTF-8.
* A range of byte values such as A0..BF indicates that any byte from A0 to BF (inclusive)
* is legal in that position.
* Any byte value outside of the ranges listed is illegal.
* For example,
* the byte sequence <C0 AF> is illegal since C0 is not legal in the 1st Byte column.
* The byte sequence <E0 9F 80> is illegal since in the row
* where E0 is legal as a first byte,
* 9F is not legal as a second byte.
* The byte sequence <F4 80 83 92> is legal, since every byte in that sequence matches
* a byte range in a row of the table (the last row).
*
*
* Table 3.1B. Legal UTF-8 Byte Sequences
* Code Points 1st Byte 2nd Byte 3rd Byte 4th Byte
* =========================================================================
* U+0000..U+007F 00..7F
* -------------------------------------------------------------------------
* U+0080..U+07FF C2..DF 80..BF
*
* -------------------------------------------------------------------------
* U+0800..U+0FFF E0 A0..BF 80..BF
* --
*
* U+1000..U+FFFF E1..EF 80..BF 80..BF
*
* --------------------------------------------------------------------------
* U+10000..U+3FFFF F0 90..BF 80..BF 80..BF
* --
* U+40000..U+FFFFF F1..F3 80..BF 80..BF 80..BF
* U+100000..U+10FFFF F4 80..8F 80..BF 80..BF
* --
* ==========================================================================
*
* Cases where a trailing byte range is not 80..BF are underlined in the table to
* draw attention to them. These occur only in the second byte of a sequence.
*
***/
XMLUInt32 tmpVal = 0;
switch(trailingBytes)
{
case 1 :
// UTF-8: [110y yyyy] [10xx xxxx]
// Unicode: [0000 0yyy] [yyxx xxxx]
//
// 0xC0, 0xC1 has been filtered out
checkTrailingBytes(*(srcPtr+1), 1, 1);
tmpVal = *srcPtr++;
tmpVal <<= 6;
tmpVal += *srcPtr++;
break;
case 2 :
// UTF-8: [1110 zzzz] [10yy yyyy] [10xx xxxx]
// Unicode: [zzzz yyyy] [yyxx xxxx]
//
if (( *srcPtr == 0xE0) && ( *(srcPtr+1) < 0xA0))
{
char byte0[2] = {*srcPtr ,0};
char byte1[2] = {*(srcPtr+1),0};
ThrowXMLwithMemMgr2(UTFDataFormatException
, XMLExcepts::UTF8_Invalid_3BytesSeq
, byte0
, byte1
, getMemoryManager());
}
checkTrailingBytes(*(srcPtr+1), 2, 1);
checkTrailingBytes(*(srcPtr+2), 2, 2);
//
// D36 (a) UTF-8 is the Unicode Transformation Format that serializes
// a Unicode code point as a sequence of one to four bytes,
// as specified in Table 3.1, UTF-8 Bit Distribution.
// (b) An illegal UTF-8 code unit sequence is any byte sequence that
// does not match the patterns listed in Table 3.1B, Legal UTF-8
// Byte Sequences.
// (c) An irregular UTF-8 code unit sequence is a six-byte sequence
// where the first three bytes correspond to a high surrogate,
// and the next three bytes correspond to a low surrogate.
// As a consequence of C12, these irregular UTF-8 sequences shall
// not be generated by a conformant process.
//
//irregular three bytes sequence
// that is zzzzyy matches leading surrogate tag 110110 or
// trailing surrogate tag 110111
// *srcPtr=1110 1101
// *(srcPtr+1)=1010 yyyy or
// *(srcPtr+1)=1011 yyyy
//
// 0xED 1110 1101
// 0xA0 1010 0000
if ((*srcPtr == 0xED) && (*(srcPtr+1) >= 0xA0))
{
char byte0[2] = {*srcPtr, 0};
char byte1[2] = {*(srcPtr+1),0};
ThrowXMLwithMemMgr2(UTFDataFormatException
, XMLExcepts::UTF8_Irregular_3BytesSeq
, byte0
, byte1
, getMemoryManager());
}
tmpVal = *srcPtr++;
tmpVal <<= 6;
tmpVal += *srcPtr++;
tmpVal <<= 6;
tmpVal += *srcPtr++;
break;
case 3 :
// UTF-8: [1111 0uuu] [10uu zzzz] [10yy yyyy] [10xx xxxx]*
// Unicode: [1101 10ww] [wwzz zzyy] (high surrogate)
// [1101 11yy] [yyxx xxxx] (low surrogate)
// * uuuuu = wwww + 1
//
if (((*srcPtr == 0xF0) && (*(srcPtr+1) < 0x90)) ||
((*srcPtr == 0xF4) && (*(srcPtr+1) > 0x8F)) )
{
char byte0[2] = {*srcPtr ,0};
char byte1[2] = {*(srcPtr+1),0};
ThrowXMLwithMemMgr2(UTFDataFormatException
, XMLExcepts::UTF8_Invalid_4BytesSeq
, byte0
, byte1
, getMemoryManager());
}
checkTrailingBytes(*(srcPtr+1), 3, 1);
checkTrailingBytes(*(srcPtr+2), 3, 2);
checkTrailingBytes(*(srcPtr+3), 3, 3);
tmpVal = *srcPtr++;
tmpVal <<= 6;
tmpVal += *srcPtr++;
tmpVal <<= 6;
tmpVal += *srcPtr++;
tmpVal <<= 6;
tmpVal += *srcPtr++;
break;
default: // trailingBytes > 3
/***
* The definition of UTF-8 in Annex D of ISO/IEC 10646-1:2000 also allows
* for the use of five- and six-byte sequences to encode characters that
* are outside the range of the Unicode character set; those five- and
* six-byte sequences are illegal for the use of UTF-8 as a transformation
* of Unicode characters. ISO/IEC 10646 does not allow mapping of unpaired
* surrogates, nor U+FFFE and U+FFFF (but it does allow other noncharacters).
***/
char len[2] = {(char)(trailingBytes+0x31), 0};
char byte[2] = {*srcPtr,0};
ThrowXMLwithMemMgr2(UTFDataFormatException
, XMLExcepts::UTF8_Exceeds_BytesLimit
, byte
, len
, getMemoryManager());
break;
}
// since trailingBytes comes from an array, this logic is redundant
// default :
// ThrowXMLwithMemMgr(TranscodingException, XMLExcepts::Trans_BadSrcSeq);
//}
tmpVal -= gUTFOffsets[trailingBytes];
//
// If it will fit into a single char, then put it in. Otherwise
// encode it as a surrogate pair. If its not valid, use the
// replacement char.
//
if (!(tmpVal & 0xFFFF0000))
{
*sizePtr++ = trailingBytes + 1;
*outPtr++ = XMLCh(tmpVal);
}
else if (tmpVal > 0x10FFFF)
{
//
// If we've gotten more than 32 chars so far, then just break
// out for now and lets process those. When we come back in
// here again, we'll get no chars and throw an exception. This
// way, the error will have a line and col number closer to
// the real problem area.
//
if ((outPtr - toFill) > 32)
break;
ThrowXMLwithMemMgr(TranscodingException, XMLExcepts::Trans_BadSrcSeq, getMemoryManager());
}
else
{
//
// If we have enough room to store the leading and trailing
// chars, then lets do it. Else, pretend this one never
// happened, and leave it for the next time. Since we don't
// update the bytes read until the bottom of the loop, by
// breaking out here its like it never happened.
//
if (outPtr + 1 >= outEnd)
break;
// Store the leading surrogate char
tmpVal -= 0x10000;
*sizePtr++ = trailingBytes + 1;
*outPtr++ = XMLCh((tmpVal >> 10) + 0xD800);
//
// And then the trailing char. This one accounts for no
// bytes eaten from the source, so set the char size for this
// one to be zero.
//
*sizePtr++ = 0;
*outPtr++ = XMLCh((tmpVal & 0x3FF) + 0xDC00);
}
}
// Update the bytes eaten
bytesEaten = srcPtr - srcData;
// Return the characters read
return outPtr - toFill;
}
XMLSize_t
XMLUTF8Transcoder::transcodeTo( const XMLCh* const srcData
, const XMLSize_t srcCount
, XMLByte* const toFill
, const XMLSize_t maxBytes
, XMLSize_t& charsEaten
, const UnRepOpts options)
{
// Watch for pathological scenario. Shouldn't happen, but...
if (!srcCount || !maxBytes)
return 0;
//
// Get pointers to our start and end points of the input and output
// buffers.
//
const XMLCh* srcPtr = srcData;
const XMLCh* srcEnd = srcPtr + srcCount;
XMLByte* outPtr = toFill;
XMLByte* outEnd = toFill + maxBytes;
while (srcPtr < srcEnd)
{
//
// Tentatively get the next char out. We have to get it into a
// 32 bit value, because it could be a surrogate pair.
//
XMLUInt32 curVal = *srcPtr;
//
// If its a leading surrogate, then lets see if we have the trailing
// available. If not, then give up now and leave it for next time.
//
unsigned int srcUsed = 1;
if ((curVal >= 0xD800) && (curVal <= 0xDBFF))
{
if (srcPtr + 1 >= srcEnd)
break;
// Create the composite surrogate pair
curVal = ((curVal - 0xD800) << 10)
+ ((*(srcPtr + 1) - 0xDC00) + 0x10000);
// And indicate that we ate another one
srcUsed++;
}
// Figure out how many bytes we need
unsigned int encodedBytes;
if (curVal < 0x80)
encodedBytes = 1;
else if (curVal < 0x800)
encodedBytes = 2;
else if (curVal < 0x10000)
encodedBytes = 3;
else if (curVal < 0x110000)
encodedBytes = 4;
else
{
// If the options say to throw, then throw
if (options == UnRep_Throw)
{
XMLCh tmpBuf[17];
XMLString::binToText(curVal, tmpBuf, 16, 16, getMemoryManager());
ThrowXMLwithMemMgr2
(
TranscodingException
, XMLExcepts::Trans_Unrepresentable
, tmpBuf
, getEncodingName()
, getMemoryManager()
);
}
// Else, use the replacement character
*outPtr++ = chSpace;
srcPtr += srcUsed;
continue;
}
//
// If we cannot fully get this char into the output buffer,
// then leave it for the next time.
//
if (outPtr + encodedBytes > outEnd)
break;
// We can do it, so update the source index
srcPtr += srcUsed;
//
// And spit out the bytes. We spit them out in reverse order
// here, so bump up the output pointer and work down as we go.
//
outPtr += encodedBytes;
switch(encodedBytes)
{
case 6 : *--outPtr = XMLByte((curVal | 0x80UL) & 0xBFUL);
curVal >>= 6;
case 5 : *--outPtr = XMLByte((curVal | 0x80UL) & 0xBFUL);
curVal >>= 6;
case 4 : *--outPtr = XMLByte((curVal | 0x80UL) & 0xBFUL);
curVal >>= 6;
case 3 : *--outPtr = XMLByte((curVal | 0x80UL) & 0xBFUL);
curVal >>= 6;
case 2 : *--outPtr = XMLByte((curVal | 0x80UL) & 0xBFUL);
curVal >>= 6;
case 1 : *--outPtr = XMLByte
(
curVal | gFirstByteMark[encodedBytes]
);
}
// Add the encoded bytes back in again to indicate we've eaten them
outPtr += encodedBytes;
}
// Fill in the chars we ate
charsEaten = (srcPtr - srcData);
// And return the bytes we filled in
return (outPtr - toFill);
}
bool XMLUTF8Transcoder::canTranscodeTo(const unsigned int toCheck)
{
// We can represent anything in the Unicode (with surrogates) range
return (toCheck <= 0x10FFFF);
}
XERCES_CPP_NAMESPACE_END