gecko-dev/intl/uconv/ucvcn/nsUnicodeToGBK.cpp

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/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/**
* A character set converter from Unicode to GBK.
*
*
* @created 08/Sept/1999
* @author Yueheng Xu, Yueheng.Xu@intel.com
* Revision History
* 04/Oct/1999. Yueheng Xu: used table gUnicodeToGBKTable[0x5200] to make
* Unicode to GB mapping fast
*/
#include "nsUnicodeToGBK.h"
#include "gbku.h"
#include "uconvutil.h"
#include "nsCharTraits.h"
//-------------------------------------------------------------
// Global table initialization function defined in gbku.h
//-------------------------------------------------------------
//-----------------------------------------------------------------------
// Private class used by nsUnicodeToGB18030 and nsUnicodeToGB18030Font0
// nsUnicodeToGB18030Uniq2Bytes
//-----------------------------------------------------------------------
static const uint16_t g_uf_gb18030_2bytes[] = {
#include "gb18030uniq2b.uf"
};
class nsUnicodeToGB18030Uniq2Bytes : public nsTableEncoderSupport
{
public:
nsUnicodeToGB18030Uniq2Bytes()
: nsTableEncoderSupport(u2BytesCharset,
(uMappingTable*) &g_uf_gb18030_2bytes, 2) {}
protected:
};
//-----------------------------------------------------------------------
// Private class used by nsUnicodeToGB18030
// nsUnicodeTo4BytesGB18030
//-----------------------------------------------------------------------
static const uint16_t g_uf_gb18030_4bytes[] = {
#include "gb180304bytes.uf"
};
class nsUnicodeTo4BytesGB18030 : public nsTableEncoderSupport
{
public:
nsUnicodeTo4BytesGB18030()
: nsTableEncoderSupport(u4BytesGB18030Charset,
(uMappingTable*) &g_uf_gb18030_4bytes, 4) {}
protected:
};
//-----------------------------------------------------------------------
// Private class used by nsUnicodeToGBK
// nsUnicodeToGBKUniq2Bytes
//-----------------------------------------------------------------------
static const uint16_t g_uf_gbk_2bytes[] = {
#include "gbkuniq2b.uf"
};
class nsUnicodeToGBKUniq2Bytes : public nsTableEncoderSupport
{
public:
nsUnicodeToGBKUniq2Bytes()
: nsTableEncoderSupport(u2BytesCharset,
(uMappingTable*) &g_uf_gbk_2bytes, 2) {}
protected:
};
//-----------------------------------------------------------------------
// nsUnicodeToGB18030
//-----------------------------------------------------------------------
void nsUnicodeToGB18030::CreateExtensionEncoder()
{
mExtensionEncoder = new nsUnicodeToGB18030Uniq2Bytes();
}
void nsUnicodeToGB18030::Create4BytesEncoder()
{
m4BytesEncoder = new nsUnicodeTo4BytesGB18030();
}
bool nsUnicodeToGB18030::EncodeSurrogate(
PRUnichar aSurrogateHigh,
PRUnichar aSurrogateLow,
char* aOut)
{
if( NS_IS_HIGH_SURROGATE(aSurrogateHigh) &&
NS_IS_LOW_SURROGATE(aSurrogateLow) )
{
// notice that idx does not include the 0x10000
uint32_t idx = ((aSurrogateHigh - (PRUnichar)0xD800) << 10 ) |
(aSurrogateLow - (PRUnichar) 0xDC00);
unsigned char *out = (unsigned char*) aOut;
// notice this is from 0x90 for supplment planes
out[0] = (idx / (10*126*10)) + 0x90;
idx %= (10*126*10);
out[1] = (idx / (10*126)) + 0x30;
idx %= (10*126);
out[2] = (idx / (10)) + 0x81;
out[3] = (idx % 10) + 0x30;
return true;
}
return false;
}
//----------------------------------------------------------------------
// Class nsUnicodeToGBK [implementation]
nsUnicodeToGBK::nsUnicodeToGBK(uint32_t aMaxLength) :
nsEncoderSupport(aMaxLength)
{
mExtensionEncoder = nullptr;
m4BytesEncoder = nullptr;
mSurrogateHigh = 0;
}
void nsUnicodeToGBK::CreateExtensionEncoder()
{
mExtensionEncoder = new nsUnicodeToGBKUniq2Bytes();
}
void nsUnicodeToGBK::Create4BytesEncoder()
{
m4BytesEncoder = nullptr;
}
bool nsUnicodeToGBK::TryExtensionEncoder(
PRUnichar aChar,
char* aOut,
int32_t *aOutLen
)
{
if( NS_IS_HIGH_SURROGATE(aChar) ||
NS_IS_LOW_SURROGATE(aChar) )
{
// performance tune for surrogate characters
return false;
}
if(! mExtensionEncoder )
CreateExtensionEncoder();
if(mExtensionEncoder)
{
int32_t len = 1;
nsresult res = NS_OK;
res = mExtensionEncoder->Convert(&aChar, &len, aOut, aOutLen);
if(NS_SUCCEEDED(res) && (*aOutLen > 0))
return true;
}
return false;
}
bool nsUnicodeToGBK::Try4BytesEncoder(
PRUnichar aChar,
char* aOut,
int32_t *aOutLen
)
{
if( NS_IS_HIGH_SURROGATE(aChar) ||
NS_IS_LOW_SURROGATE(aChar) )
{
// performance tune for surrogate characters
return false;
}
if(! m4BytesEncoder )
Create4BytesEncoder();
if(m4BytesEncoder)
{
int32_t len = 1;
nsresult res = NS_OK;
res = m4BytesEncoder->Convert(&aChar, &len, aOut, aOutLen);
NS_ASSERTION(NS_FAILED(res) || ((1 == len) && (4 == *aOutLen)),
"unexpect conversion length");
if(NS_SUCCEEDED(res) && (*aOutLen > 0))
return true;
}
return false;
}
bool nsUnicodeToGBK::EncodeSurrogate(
PRUnichar aSurrogateHigh,
PRUnichar aSurrogateLow,
char* aOut)
{
return false; // GBK cannot encode Surrogate, let the subclass encode it.
}
NS_IMETHODIMP nsUnicodeToGBK::ConvertNoBuff(
const PRUnichar * aSrc,
int32_t * aSrcLength,
char * aDest,
int32_t * aDestLength)
{
int32_t iSrcLength = 0;
int32_t iDestLength = 0;
PRUnichar unicode;
nsresult res = NS_OK;
while (iSrcLength < *aSrcLength )
{
unicode = *aSrc;
//if unicode's hi byte has something, it is not ASCII, must be a GB
if(IS_ASCII(unicode))
{
// this is an ASCII
*aDest = CAST_UNICHAR_TO_CHAR(*aSrc);
aDest++; // increment 1 byte
iDestLength +=1;
} else {
char byte1, byte2;
if(mUtil.UnicodeToGBKChar( unicode, false, &byte1, &byte2))
{
// make sure we still have 2 bytes for output first
if(iDestLength+2 > *aDestLength)
{
res = NS_OK_UENC_MOREOUTPUT;
break;
}
aDest[0] = byte1;
aDest[1] = byte2;
aDest += 2; // increment 2 bytes
iDestLength +=2;
} else {
int32_t aOutLen = 2;
// make sure we still have 2 bytes for output first
if(iDestLength+2 > *aDestLength)
{
res = NS_OK_UENC_MOREOUTPUT;
break;
}
// we cannot map in the common mapping. Let's try to
// call the delegated 2 byte converter for the gbk or gb18030
// unique 2 byte mapping
if(TryExtensionEncoder(unicode, aDest, &aOutLen))
{
iDestLength += aOutLen;
aDest += aOutLen;
} else {
// make sure we still have 4 bytes for output first
if(iDestLength+4 > *aDestLength)
{
res = NS_OK_UENC_MOREOUTPUT;
break;
}
// we still cannot map. Let's try to
// call the delegated GB18030 4 byte converter
aOutLen = 4;
if( NS_IS_HIGH_SURROGATE(unicode) )
{
if((iSrcLength+1) < *aSrcLength ) {
if(EncodeSurrogate(aSrc[0],aSrc[1], aDest)) {
// since we got a surrogate pair, we need to increment src.
iSrcLength++ ;
aSrc++;
iDestLength += aOutLen;
aDest += aOutLen;
} else {
// only get a high surrogate, but not a low surrogate
res = NS_ERROR_UENC_NOMAPPING;
iSrcLength++; // include length of the unmapped character
break;
}
} else {
mSurrogateHigh = aSrc[0];
break; // this will go to afterwhileloop
}
} else {
if( NS_IS_LOW_SURROGATE(unicode) )
{
if(NS_IS_HIGH_SURROGATE(mSurrogateHigh)) {
if(EncodeSurrogate(mSurrogateHigh, aSrc[0], aDest)) {
iDestLength += aOutLen;
aDest += aOutLen;
} else {
// only get a high surrogate, but not a low surrogate
res = NS_ERROR_UENC_NOMAPPING;
iSrcLength++; // include length of the unmapped character
break;
}
} else {
// only get a low surrogate, but not a low surrogate
res = NS_ERROR_UENC_NOMAPPING;
iSrcLength++; // include length of the unmapped character
break;
}
} else {
if(Try4BytesEncoder(unicode, aDest, &aOutLen))
{
NS_ASSERTION((aOutLen == 4), "we should always generate 4 bytes here");
iDestLength += aOutLen;
aDest += aOutLen;
} else {
res = NS_ERROR_UENC_NOMAPPING;
iSrcLength++; // include length of the unmapped character
break;
}
}
}
}
}
}
iSrcLength++ ; // Each unicode char just count as one in PRUnichar string;
mSurrogateHigh = 0;
aSrc++;
if ( iDestLength >= (*aDestLength) && (iSrcLength < *aSrcLength) )
{
res = NS_OK_UENC_MOREOUTPUT;
break;
}
}
//afterwhileloop:
*aDestLength = iDestLength;
*aSrcLength = iSrcLength;
return res;
}