// helper functions
BOOL CMP3Info::GetNextFrameHeader(HANDLE hFile, MP3FRAMEHEADER* pHeader, int nPassBytes)
{
memset(pHeader,0,sizeof(*pHeader));
if (nPassBytes > 0)
SetFilePointer(hFile,nPassBytes,NULL,FILE_CURRENT);
int n = 0;
BOOL bReadOK;
DWORD dwNumBytesRead;
do
{
bReadOK = ReadFile(hFile,pHeader,4,&dwNumBytesRead,NULL);
ChangeEndian(pHeader,4); // convert from big-endian to little-endian
// only search in 10kb
if (!bReadOK || dwNumBytesRead != 4 ||
pHeader->framesync == 0x7FF || ++n > 10000)
break;
SetFilePointer(hFile,-3,NULL,FILE_CURRENT);
}
while (1);
return (pHeader->framesync == 0x7FF);
}
uint32_t NormalUart::Send(uint32_t *Data, uint32_t Length)
{
SendHeader(&mH);
for (uint32_t i = 0; i < Length; ++i){
SendInt(&mH,Data[i]);
}
ChangeEndian(Data,Length*sizeof(uint32_t));
crcInit();
crc checksum = crcFast((unsigned char*)Data,Length*sizeof(uint32_t));
//ChangeEndian(&checksum,1);
SendInt(&mH,checksum);
return Length;
}
// Decode pIntput into pOutput. Input length in lSize. Input buffer and
// output buffer can be the same, but be sure buffer length is even MOD8.
void CBlowFish::Decode (BYTE * pInput, BYTE * pOutput, DWORD lSize)
{
DWORD lCount ;
BYTE *pi, *po ;
int i ;
int SameDest = (pInput == pOutput ? 1 : 0) ;
#ifdef ORDER_ABCD
//force data to little endian form
BYTE *pszStart = pOutput;
ChangeEndian(pszStart, lSize);
#endif
for (lCount = 0 ; lCount < lSize ; lCount += 8)
{
if (SameDest) // if encoded data is being written into input buffer
{
Blowfish_decipher ((DWORD *) pInput, (DWORD *) (pInput + 4));
pInput += 8 ;
}
else // output buffer not equal to input buffer
{ // so copy input to output before decoding
pi = pInput ;
po = pOutput ;
for (i = 0 ; i < 8 ; i++)
*po++ = *pi++ ;
Blowfish_decipher ((DWORD *) pOutput, (DWORD *) (pOutput + 4));
pInput += 8 ;
pOutput += 8 ;
}
}
#ifdef ORDER_ABCD
// change back to the big endian form
ChangeEndian(pszStart, lSize);
#endif
}
// Encode pIntput into pOutput. Input length in lSize. Returned value
// is length of output which will be even MOD 8 bytes. Input buffer and
// output buffer can be the same, but be sure buffer length is even MOD8.
DWORD CBlowFish::Encode (BYTE * pInput, BYTE * pOutput, DWORD lSize)
{
DWORD lCount, lOutSize, lGoodBytes;
BYTE *pi, *po;
int i, j;
int SameDest = (pInput == pOutput ? 1 : 0);
lOutSize = GetOutputLength (lSize);
#ifdef ORDER_ABCD
//force data to little endian form
BYTE *pszStart = pOutput;
ChangeEndian(pOutput, lOutSize);
#endif
for (lCount = 0; lCount < lOutSize; lCount += 8)
{
if (SameDest) // if encoded data is being written into input buffer
{
if (lCount < lSize - 7) // if not dealing with uneven bytes at end
{
Blowfish_encipher ((DWORD *) pInput, (DWORD *) (pInput + 4)) ;
}
else // pad end of data with null bytes to complete encryption
{
po = pInput + lSize; // point at byte past the end of actual data
j = (int) (lOutSize - lSize); // number of bytes to set to null
for (i = 0; i < j; i++)
*po++ = 0;
Blowfish_encipher ((DWORD *) pInput, (DWORD *) (pInput + 4)) ;
}
pInput += 8;
}
else // output buffer not equal to input buffer, so must copy
{ // input to output buffer prior to encrypting
if (lCount < lSize - 7) // if not dealing with uneven bytes at end
{
pi = pInput;
po = pOutput;
for (i = 0 ; i < 8 ; i++) // copy bytes to output
*po++ = *pi++;
Blowfish_encipher ((DWORD *) pOutput, (DWORD *) (pOutput + 4)); // now encrypt them
}
else // pad end of data with null bytes to complete encryption
{
lGoodBytes = lSize - lCount; // number of remaining data bytes
po = pOutput;
for (i = 0; i < (int) lGoodBytes ; i++)
*po++ = *pInput++;
for (j = i; j < 8; j++)
*po++ = 0;
Blowfish_encipher ((DWORD *) pOutput, (DWORD *) (pOutput + 4));
}
pInput += 8;
pOutput += 8;
}
}
#ifdef ORDER_ABCD
// change back to the big endian form
ChangeEndian(pszStart, lOutSize);
#endif
return lOutSize;
}
