/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* ***** BEGIN LICENSE BLOCK ***** * Version: MPL 1.1/GPL 2.0/LGPL 2.1 * * The contents of this file are subject to the Mozilla 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/MPL/ * * 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 the Initial Developer are Copyright (C) 1998 * the Initial Developer. All Rights Reserved. * * Contributor(s): * * Alternatively, the contents of this file may be used under the terms of * either of the GNU General Public License Version 2 or later (the "GPL"), * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), * in which case the provisions of the GPL or the LGPL are applicable instead * of those above. If you wish to allow use of your version of this file only * under the terms of either the GPL or the LGPL, and not to allow others to * use your version of this file under the terms of the MPL, indicate your * decision by deleting the provisions above and replace them with the notice * and other provisions required by the GPL or the LGPL. If you do not delete * the provisions above, a recipient may use your version of this file under * the terms of any one of the MPL, the GPL or the LGPL. * * ***** END LICENSE BLOCK ***** */ /** * 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. * * Earlier versions of the converter said: * "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." * However, testing in current versions of IE shows that it only accepts * 8-bit characters when the converter is in GB state, and when in ASCII * state each single 8-bit character is converted to U+FFFD * * 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" #include "gbku.h" //---------------------------------------------------------------------- // Class nsHZToUnicode [implementation] //---------------------------------------------------------------------- // Subclassing of nsTablesDecoderSupport class [implementation] #define HZ_STATE_GB 1 #define HZ_STATE_ASCII 2 #define HZ_STATE_ODD_BYTE_FLAG 0x80 #define HZLEAD1 '~' #define HZLEAD2 '{' #define HZLEAD3 '}' #define HZ_ODD_BYTE_STATE (mHZState & (HZ_STATE_ODD_BYTE_FLAG)) #define HZ_ENCODING_STATE (mHZState & ~(HZ_STATE_ODD_BYTE_FLAG)) nsHZToUnicode::nsHZToUnicode() : nsBufferDecoderSupport(1) { mHZState = HZ_STATE_ASCII; // per HZ spec, default to ASCII state mRunLength = 0; mOddByte = 0; } //Overwriting the ConvertNoBuff() in nsUCvCnSupport.cpp. NS_IMETHODIMP nsHZToUnicode::ConvertNoBuff( const char* aSrc, PRInt32 * aSrcLength, PRUnichar *aDest, PRInt32 * aDestLength) { PRInt32 i=0; PRInt32 iSrcLength = *aSrcLength; PRInt32 iDestlen = 0; *aSrcLength=0; nsresult res = NS_OK; char oddByte = mOddByte; for (i=0; i= (*aDestLength)) { res = NS_OK_UDEC_MOREOUTPUT; break; } char srcByte = *aSrc++; (*aSrcLength)++; if (!HZ_ODD_BYTE_STATE) { if (srcByte == HZLEAD1 || (HZ_ENCODING_STATE == HZ_STATE_GB && (UINT8_IN_RANGE(0x21, srcByte, 0x7E) || UINT8_IN_RANGE(0x81, srcByte, 0xFE)))) { oddByte = srcByte; mHZState |= HZ_STATE_ODD_BYTE_FLAG; } else { *aDest++ = (srcByte & 0x80) ? UCS2_NO_MAPPING : CAST_CHAR_TO_UNICHAR(srcByte); iDestlen++; } } else { if (oddByte & 0x80) { // Accept legal 8-bit GB 2312-80 sequences in GB mode only NS_ASSERTION(HZ_ENCODING_STATE == HZ_STATE_GB, "Invalid lead byte in ASCII mode"); *aDest++ = (UINT8_IN_RANGE(0x81, oddByte, 0xFE) && UINT8_IN_RANGE(0x40, srcByte, 0xFE)) ? mUtil.GBKCharToUnicode(oddByte, srcByte) : UCS2_NO_MAPPING; mRunLength++; iDestlen++; // otherwise, it is a 7-bit byte // The source will be an ASCII or a 7-bit HZ code depending on oddByte } else if (oddByte == HZLEAD1) { // if it is lead by '~' switch (srcByte) { case HZLEAD2: // we got a '~{' // we are switching to HZ state mHZState = HZ_STATE_GB; mRunLength = 0; break; case HZLEAD3: // we got a '~}' // we are switching to ASCII state mHZState = HZ_STATE_ASCII; if (mRunLength == 0) { *aDest++ = UCS2_NO_MAPPING; iDestlen++; } mRunLength = 0; break; case HZLEAD1: // we got a '~~', process like an ASCII, but no state change *aDest++ = CAST_CHAR_TO_UNICHAR(srcByte); iDestlen++; mRunLength++; break; default: // Undefined ESC sequence '~X': treat as an error if X is a // printable character or we are in ASCII mode, and resynchronize // on the second character. // // N.B. For compatibility with other implementations, we treat '~\n' // as an illegal sequence even though RFC1843 permits it, and for // the same reason we pass through control characters including '\n' // and ' ' even in GB mode. if (srcByte > 0x20 || HZ_ENCODING_STATE == HZ_STATE_ASCII) { *aDest++ = UCS2_NO_MAPPING; } aSrc--; (*aSrcLength)--; iDestlen++; break; } } else if (HZ_ENCODING_STATE == HZ_STATE_GB) { *aDest++ = (UINT8_IN_RANGE(0x21, oddByte, 0x7E) && UINT8_IN_RANGE(0x21, srcByte, 0x7E)) ? mUtil.GBKCharToUnicode(oddByte|0x80, srcByte|0x80) : UCS2_NO_MAPPING; mRunLength++; iDestlen++; } else { NS_NOTREACHED("2-byte sequence that we don't know how to handle"); *aDest++ = UCS2_NO_MAPPING; iDestlen++; } oddByte = 0; mHZState &= ~HZ_STATE_ODD_BYTE_FLAG; } } // for loop mOddByte = HZ_ODD_BYTE_STATE ? oddByte : 0; *aDestLength = iDestlen; return res; }