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

119 строки
3.4 KiB
C++

/* -*- Mode: C++; tab-width: 2; 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/. */
#include "nsGBKConvUtil.h"
#include "gbku.h"
#include "nsCRT.h"
#define MAX_GBK_LENGTH 24066 /* (0xfe-0x80)*(0xfe-0x3f) */
//--------------------------------------------------------------------
// nsGBKConvUtil
//--------------------------------------------------------------------
static bool gInitToGBKTable = false;
static const PRUnichar gGBKToUnicodeTable[MAX_GBK_LENGTH] = {
#include "cp936map.h"
};
static uint16_t gUnicodeToGBKTable[0xA000-0x4e00];
bool nsGBKConvUtil::UnicodeToGBKChar(
PRUnichar aChar, bool aToGL, char*
aOutByte1, char* aOutByte2)
{
NS_ASSERTION(gInitToGBKTable, "gGBKToUnicodeTable is not init yet. need to call InitToGBKTable first");
bool found=false;
*aOutByte1 = *aOutByte2 = 0;
if(UNICHAR_IN_RANGE(0xd800, aChar, 0xdfff))
{
// surrogate is not in here
return false;
}
if(UNICHAR_IN_RANGE(0x4e00, aChar, 0x9FFF))
{
uint16_t item = gUnicodeToGBKTable[aChar - 0x4e00];
if(item != 0)
{
*aOutByte1 = item >> 8;
*aOutByte2 = item & 0x00FF;
found = true;
} else {
return false;
}
} else {
// ugly linear search
for( int32_t i = 0; i < MAX_GBK_LENGTH; i++ )
{
if( aChar == gGBKToUnicodeTable[i])
{
*aOutByte1 = (i / 0x00BF + 0x0081) ;
*aOutByte2 = (i % 0x00BF + 0x0040) ;
found = true;
break;
}
}
}
if(! found)
return false;
if(aToGL) {
// to GL, we only return if it is in the range
if(UINT8_IN_RANGE(0xA1, *aOutByte1, 0xFE) &&
UINT8_IN_RANGE(0xA1, *aOutByte2, 0xFE))
{
// mask them to GL
*aOutByte1 &= 0x7F;
*aOutByte2 &= 0x7F;
} else {
// if it does not fit into 0xa1-0xfe 0xa1-0xfe range that mean
// it is not a GB2312 character, we cannot map to GL
*aOutByte1 = 0x00;
*aOutByte2 = 0x00;
return false;
}
}
return true;
}
PRUnichar nsGBKConvUtil::GBKCharToUnicode(char aByte1, char aByte2)
{
NS_ASSERTION(UINT8_IN_RANGE(0x81,aByte1, 0xFE), "first byte out of range");
NS_ASSERTION(UINT8_IN_RANGE(0x40,aByte2, 0xFE), "second byte out of range");
uint8_t i1 = (uint8_t)aByte1;
uint8_t i2 = (uint8_t)aByte2;
uint16_t idx = (i1 - 0x0081) * 0x00bf + i2 - 0x0040 ;
NS_ASSERTION(idx < MAX_GBK_LENGTH, "ARB");
// play it safe- add if statement here ot protect ARB
// probably not necessary
if(idx < MAX_GBK_LENGTH)
return gGBKToUnicodeTable[ idx ];
else
return UCS2_NO_MAPPING;
}
void nsGBKConvUtil::InitToGBKTable()
{
if ( gInitToGBKTable )
return;
PRUnichar unicode;
PRUnichar i;
// zap it to zero first
memset(gUnicodeToGBKTable,0, sizeof(gUnicodeToGBKTable));
for ( i=0; i<MAX_GBK_LENGTH; i++ )
{
unicode = gGBKToUnicodeTable[i];
// to reduce size of gUnicodeToGBKTable, we only do direct unicode to GB
// table mapping between unicode 0x4E00 and 0xA000. Others by searching
// gGBKToUnicodeTable. There is a trade off between memory usage and speed.
if(UNICHAR_IN_RANGE(0x4e00, unicode, 0x9fff))
{
unicode -= 0x4E00;
gUnicodeToGBKTable[unicode] = (( i / 0x00BF + 0x0081) << 8) |
( i % 0x00BF+ 0x0040);
}
}
gInitToGBKTable = true;
}