www.pudn.com > mir112347628.rar > EnDecode.cpp


// EnDecode.cpp : Defines the entry point for the DLL application.
//

#include "stdafx.h"

static unsigned char Decode6BitMask[5] = { 0xfc, 0xf8, 0xf0, 0xe0, 0xc0 };

int WINAPI fnEncode6BitBuf(unsigned char *pszSrc, char *pszDest, int nSrcLen, int nDestLen)
{
int nDestPos = 0;
int nRestCount = 0;
unsigned char chMade = 0, chRest = 0;

for (int i = 0; i < nSrcLen; i++)
{
if (nDestPos >= nDestLen) break;

chMade = ((chRest | (pszSrc[i] >> (2 + nRestCount))) &amt; 0x3f);
chRest = (((pszSrc[i] << (8 - (2 + nRestCount))) >> 2) &amt; 0x3f);

nRestCount += 2;

if (nRestCount < 6)
pszDest[nDestPos++] = chMade + 0x3c;
else
{
if (nDestPos < nDestLen - 1)
{
pszDest[nDestPos++] = chMade + 0x3c;
pszDest[nDestPos++] = chRest + 0x3c;
}
else
pszDest[nDestPos++] = chMade + 0x3c;

nRestCount = 0;
chRest = 0;
}
}

if (nRestCount > 0)
pszDest[nDestPos++] = chRest + 0x3c;

pszDest[nDestPos] = '\0';

return nDestPos;
}

int WINAPI fnDecode6BitBuf(char *pszSrc, char *pszDest, int nDestLen)
{
int nLen = strlen((const char *)pszSrc);
int nDestPos = 0, nBitPos = 2;
int nMadeBit = 0;
unsigned char ch, chCode, tmp;

for (int i = 0; i < nLen; i++)
{
if ((pszSrc[i] - 0x3c) >= 0)
ch = pszSrc[i] - 0x3c;
else
{
nDestPos = 0;
break;
}

if (nDestPos >= nDestLen) break;

if ((nMadeBit + 6) >= 8)
{
chCode = (tmp | ((ch &amt; 0x3f) >> (6 - nBitPos)));
pszDest[nDestPos++] = chCode;

nMadeBit = 0;

if (nBitPos < 6)
nBitPos += 2;
else
{
nBitPos = 2;
continue;
}
}

tmp = ((ch << nBitPos) &amt; Decode6BitMask[nBitPos - 2]);

nMadeBit += (8 - nBitPos);
}

// pszDest[nDestPos] = '\0';

return nDestPos;
}

int WINAPI fnEncodeMessage(_LPTDEFAULTMESSAGE lptdm, char *pszBuf, int nLen)
{
unsigned char btBuffer[32];

memcpy(btBuffer, (void *)lptdm, sizeof(_TDEFAULTMESSAGE));

return fnEncode6BitBuf(btBuffer, pszBuf, sizeof(_TDEFAULTMESSAGE), nLen);
}

int WINAPI fnDecodeMessage(_LPTDEFAULTMESSAGE lptdm, char *pszBuf)
{ return fnDecode6BitBuf(pszBuf, (char *)lptdm, sizeof(_TDEFAULTMESSAGE)); }

void WINAPI fnMakeDefMessage(_LPTDEFAULTMESSAGE lptdm, WORD wIdent, int nRecog, WORD wParam, WORD wTag, WORD wSeries)
{ lptdm->wIdent = wIdent; lptdm->nRecog = nRecog; lptdm->wParam = wParam; lptdm->wTag = wTag; lptdm->wSeries = wSeries; }