michael@0: /* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0:  /**
michael@0:  * A character set converter from Unicode to HZ.
michael@0:  * 
michael@0:  *
michael@0:  * @created         08/Sept/1999
michael@0:  * @author  Yueheng Xu, Yueheng.Xu@intel.com
michael@0:  * Revision History
michael@0:  * 04/Oct/1999. Yueheng Xu: Fixed line continuation problem when line 
michael@0:  *                          ended by '~';
michael@0:  *              Used table UnicodeToGBK[] to speed up the mapping.
michael@0:  */
michael@0: #include "nsUnicodeToHZ.h"
michael@0: #include "gbku.h"
michael@0: //----------------------------------------------------------------------
michael@0: // Class nsUnicodeToGBK [implementation]
michael@0: #define HZ_STATE_GB		1
michael@0: #define HZ_STATE_ASCII	2
michael@0: #define HZ_STATE_TILD	3
michael@0: #define HZLEAD1 '~'
michael@0: #define HZLEAD2 '{'
michael@0: #define HZLEAD3 '}'
michael@0: #define UNICODE_TILD	0x007E
michael@0: nsUnicodeToHZ::nsUnicodeToHZ() : nsEncoderSupport(6)
michael@0: {
michael@0:   mHZState = HZ_STATE_ASCII;	// per HZ spec, default to HZ mode
michael@0: }
michael@0: NS_IMETHODIMP nsUnicodeToHZ::ConvertNoBuff(
michael@0:   const char16_t * aSrc, 
michael@0:   int32_t * aSrcLength, 
michael@0:   char * aDest, 
michael@0:   int32_t * aDestLength)
michael@0: {
michael@0:   int32_t i=0;
michael@0:   int32_t iSrcLength = *aSrcLength;
michael@0:   int32_t iDestLength = 0;
michael@0: 
michael@0:   for (i=0;i< iSrcLength;i++)
michael@0:   {
michael@0:     if(! IS_ASCII(*aSrc))
michael@0:     {
michael@0:       // hi byte has something, it is not ASCII, process as a GB
michael@0:       if ( mHZState != HZ_STATE_GB )
michael@0:       {
michael@0:         // we are adding a '~{' ESC sequence to star a HZ string
michael@0:         mHZState = HZ_STATE_GB;
michael@0:         aDest[0] = '~';
michael@0:         aDest[1] = '{';
michael@0:         aDest += 2;	// increment 2 bytes
michael@0:         iDestLength +=2;
michael@0:       }
michael@0:       if(mUtil.UnicodeToGBKChar(*aSrc, true, &aDest[0], &aDest[1])) {
michael@0:         aDest += 2;	// increment 2 bytes
michael@0:         iDestLength +=2;
michael@0:       } else {
michael@0:         // some thing that we cannot convert
michael@0:         // xxx fix me ftang
michael@0:         // error handling here
michael@0:       }
michael@0:     } else {
michael@0:       // this is an ASCII
michael@0: 
michael@0:       // if we are in HZ mode, end it by adding a '~}' ESC sequence
michael@0:       if ( mHZState == HZ_STATE_GB )
michael@0:       {
michael@0:         mHZState = HZ_STATE_ASCII;
michael@0:         aDest[0] = '~';
michael@0:         aDest[1] = '}';
michael@0:         aDest += 2; // increment 2 bytes
michael@0:         iDestLength +=2;
michael@0:       }
michael@0:           
michael@0:       // if this is a regular char '~' , convert it to two '~'
michael@0:       if ( *aSrc == UNICODE_TILD )
michael@0:       {
michael@0:         aDest[0] = '~';
michael@0:         aDest[1] = '~';
michael@0:         aDest += 2; // increment 2 bytes
michael@0:         iDestLength +=2;
michael@0:       } else {
michael@0:         // other regular ASCII chars convert by normal ways
michael@0: 	
michael@0:         // Is this works for both little endian and big endian machines ?
michael@0:         *aDest = (char) ( (char16_t)(*aSrc) );
michael@0:         aDest++; // increment 1 byte
michael@0:         iDestLength +=1;
michael@0:       }
michael@0:     }
michael@0:     aSrc++;	 // increment 2 bytes
michael@0:     if ( iDestLength >= (*aDestLength) )
michael@0:     {
michael@0:       break;
michael@0:     }
michael@0:   }
michael@0:   *aDestLength = iDestLength;
michael@0:   *aSrcLength = i;
michael@0:   return NS_OK;
michael@0: }
michael@0: 
michael@0: NS_IMETHODIMP nsUnicodeToHZ::FinishNoBuff(char * aDest, int32_t * aDestLength)
michael@0: {
michael@0:   if ( mHZState == HZ_STATE_GB )
michael@0:   {
michael@0:     // if we are in HZ mode, end it by adding a '~}' ESC sequence
michael@0:     mHZState = HZ_STATE_ASCII;
michael@0:     aDest[0] = '~';
michael@0:     aDest[1] = '}';
michael@0:     *aDestLength = 2;
michael@0:   } else {
michael@0:     *aDestLength = 0;
michael@0:   }
michael@0:   return NS_OK;
michael@0: }