void CBitRead::GrabNextDWord(bool bOverFlowImmediately) {
if (m_pDataIn == m_pBufferEnd) {
m_nBitsAvail = 1; // so that next read will run out of words
m_nInBufWord = 0;
m_pDataIn++; // so seek count increments like old
if (bOverFlowImmediately) {
SetOverflowFlag();
}
} else if (m_pDataIn > m_pBufferEnd) {
SetOverflowFlag();
m_nInBufWord = 0;
} else {
assert(reinterpret_cast<size_t>(m_pDataIn) + 3 < reinterpret_cast<size_t>(m_pBufferEnd));
m_nInBufWord = *(m_pDataIn++);
}
}
bool bf_write::WriteBits(const void *pInData, int nBits)
{
#if defined( BB_PROFILING )
VPROF( "bf_write::WriteBits" );
#endif
unsigned char *pOut = (unsigned char*)pInData;
int nBitsLeft = nBits;
if((m_iCurBit+nBits) > m_nDataBits)
{
SetOverflowFlag();
CallErrorHandler( BITBUFERROR_BUFFER_OVERRUN, GetDebugName() );
return false;
}
// Get output dword-aligned.
while(((unsigned long)pOut & 3) != 0 && nBitsLeft >= 8)
{
WriteUBitLong( *pOut, 8, false );
++pOut;
nBitsLeft -= 8;
}
// check if we can use fast memcpy if m_iCurBit is byte aligned
if ( (nBitsLeft >= 32) && (m_iCurBit & 7) == 0 )
{
int numbytes = (nBitsLeft >> 3);
int numbits = numbytes << 3;
// Bounds checking..
// TODO: May not need this check anymore
if((m_iCurBit+numbits) > m_nDataBits)
{
m_iCurBit = m_nDataBits;
SetOverflowFlag();
CallErrorHandler( BITBUFERROR_BUFFER_OVERRUN, GetDebugName() );
return false;
}
Q_memcpy( m_pData+(m_iCurBit>>3), pOut, numbytes );
pOut += numbytes;
nBitsLeft -= numbits;
m_iCurBit += numbits;
}
bool old_bf_write::WriteBits(const void *pInData, int nBits)
{
#if defined( BB_PROFILING )
VPROF( "old_bf_write::WriteBits" );
#endif
unsigned char *pOut = (unsigned char*)pInData;
int nBitsLeft = nBits;
// Bounds checking..
if ( (m_iCurBit+nBits) > m_nDataBits )
{
SetOverflowFlag();
CallErrorHandler( BITBUFERROR_BUFFER_OVERRUN, GetDebugName() );
return false;
}
// Align output to dword boundary
while (((unsigned long)pOut & 3) != 0 && nBitsLeft >= 8)
{
WriteUBitLong( *pOut, 8, false );
++pOut;
nBitsLeft -= 8;
}
if ( IsPC() && (nBitsLeft >= 32) && (m_iCurBit & 7) == 0 )
{
// current bit is byte aligned, do block copy
int numbytes = nBitsLeft >> 3;
int numbits = numbytes << 3;
Q_memcpy( m_pData+(m_iCurBit>>3), pOut, numbytes );
pOut += numbytes;
nBitsLeft -= numbits;
m_iCurBit += numbits;
}
