/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- * * The contents of this file are subject to the Netscape Public * License Version 1.1 (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.mozilla.org/NPL/ * * Software distributed under the License is distributed on an "AS * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or * implied. See the License for the specific language governing * rights and limitations under the License. * * The Original Code is mozilla.org code. * * The Initial Developer of the Original Code is Netscape * Communications Corporation. Portions created by Netscape are * Copyright (C) 1998 Netscape Communications Corporation. All * Rights Reserved. * * Contributor(s): * * This HZ to Unicode converter is a contribution from Intel Corporation to the mozilla * project. */ /** * A character set converter from HZ to Unicode. * * * @created 08/Sept/1999 * @author Yueheng Xu, Yueheng.Xu@intel.com * * Note: in this HZ-GB-2312 converter, we accept a string composed of 7-bit HZ * encoded Chinese chars,as it is defined in RFC1843 available at * http://www.cis.ohio-state.edu/htbin/rfc/rfc1843.html * and RFC1842 available at http://www.cis.ohio-state.edu/htbin/rfc/rfc1842.html. * * In an effort to match the similar extended capability of Microsoft Internet Explorer * 5.0. We also accept the 8-bit GB encoded chars mixed in a HZ string. * But this should not be a recommendedd practice for HTML authors. * * The priority of converting are as follows: first convert 8-bit GB code; then, * consume HZ ESC sequences such as '~{', '~}', '~~'; then, depending on the current * state ( default to ASCII state ) of the string, each 7-bit char is converted as an * ASCII, or two 7-bit chars are converted into a Chinese character. */ #include "nsUCvCnDll.h" #include "nsHZToUnicode.h" #define _GBKU_TABLE_ // to use a shared GBKU table #include "gbku.h" //---------------------------------------------------------------------- // Class nsHZToUnicode [implementation] nsresult nsHZToUnicode::CreateInstance(nsISupports ** aResult) { *aResult = new nsHZToUnicode(); return (*aResult == NULL)? NS_ERROR_OUT_OF_MEMORY : NS_OK; } //---------------------------------------------------------------------- // Subclassing of nsTablesDecoderSupport class [implementation] NS_IMETHODIMP nsHZToUnicode::GetMaxLength(const char * aSrc, PRInt32 aSrcLength, PRInt32 * aDestLength) { *aDestLength = aSrcLength; return NS_OK; } //convert the 7-bit HZ into an 8-bit GB index of the GBK table and get its unicode void nsHZToUnicode::HZToUnicode(DByte *pGBCode, PRUnichar * pUnicode) { //we are re-using the GBK's GB to Unicode mapping table. PRUint16 iGBKToUnicodeIndex = 0; PRUint8 left, right; *pUnicode = 0xFFFF; if(pGBCode) { left = pGBCode->leftbyte | 0x80; right = pGBCode->rightbyte | 0x80; iGBKToUnicodeIndex = (left - 0x0081)*0x00BF + (right - 0x0040); } *pUnicode = GBKToUnicodeTable[iGBKToUnicodeIndex]; } //convert the 8-bit GB index to its unicode by GBK table void nsHZToUnicode::GBToUnicode(DByte *pGBCode, PRUnichar * pUnicode) { //we are re-using the GBK's GB to Unicode mapping table. PRUint16 iGBKToUnicodeIndex = 0; PRUint8 left, right; *pUnicode = 0xFFFF; if(pGBCode) { left = pGBCode->leftbyte; right = pGBCode->rightbyte; iGBKToUnicodeIndex = (left - 0x0081)*0x00BF + (right - 0x0040); } *pUnicode = GBKToUnicodeTable[iGBKToUnicodeIndex]; } //Overwriting the ConvertNoBuff() in nsUCvCnSupport.cpp. NS_IMETHODIMP nsHZToUnicode::ConvertNoBuff(const char* aSrc, PRInt32 * aSrcLength, PRUnichar *aDest, PRInt32 * aDestLength) { #define HZ_STATE_GB 1 #define HZ_STATE_ASCII 2 #define HZ_STATE_TILD 3 #define HZLEAD1 '~' #define HZLEAD2 '{' #define HZLEAD3 '}' #define HZLEAD4 '\n' static PRInt16 hz_state = HZ_STATE_ASCII; // per HZ spec, default to ASCII state PRInt32 i=0; PRInt32 iSrcLength = *aSrcLength; DByte *pSrcDBCode = (DByte *)aSrc; PRUnichar *pDestDBCode = (PRUnichar *)aDest; PRInt32 iDestlen = 0; PRUint8 ch1, ch2; nsresult res = NS_OK; for (i=0;i= (*aDestLength) ) { res = NS_OK_UDEC_MOREOUTPUT; break; } if ( *aSrc & 0x80 ) // if it is a 8-bit byte { // The source is a 8-bit GBCode GBToUnicode(pSrcDBCode, pDestDBCode); aSrc += 2; i++; iDestlen++; aDest++; *aSrcLength = i+1; continue; } // otherwise, it is a 7-bit byte // The source will be an ASCII or a 7-bit HZ code depending on ch1 ch1 = *aSrc; ch2 = *(aSrc+1); if (ch1 == HZLEAD1 ) // if it is lead by '~' { switch (ch2) { case HZLEAD2: // we got a '~{' // we are switching to HZ state hz_state = HZ_STATE_GB; aSrc += 2; i++; break; case HZLEAD3: // we got a '~}' // we are switching to ASCII state hz_state = HZ_STATE_ASCII; aSrc += 2; i++; break; case HZLEAD1: // we got a '~~', process like an ASCII, but no state change aSrc++; *pDestDBCode = (PRUnichar) ( ((char)(*aSrc) )& 0x00ff); aSrc++; i++; iDestlen++; aDest++; break; case HZLEAD4: // we got a "~\n", it means maintain double byte mode cross lines, ignore the '~' itself // hz_state = HZ_STATE_GB; // I find that "~\n" should interpreted as line continuation without mode change // It should not be interpreted as line continuation with double byte mode on aSrc++; break; default: // undefined ESC sequence '~X' are ignored since this is a illegal combination aSrc += 2; break; }; continue;// go for next loop } // ch1 != '~' switch (hz_state) { case HZ_STATE_GB: // the following chars are HZ HZToUnicode(pSrcDBCode, pDestDBCode); aSrc += 2; i++; iDestlen++; aDest++; break; case HZ_STATE_ASCII: default: // default behavior also like an ASCII // when the source is an ASCII *pDestDBCode = (PRUnichar) ( ((char)(*aSrc) )& 0x00ff); aSrc++; iDestlen++; aDest++; break; } *aSrcLength = i+1; }// for loop *aDestLength = iDestlen; return NS_OK; }