Method BuffAddByte

ImgDecode.cpp:1386–1573

Add a byte to the scan buffer from the file - Handle stuff bytes - Handle restart markers PRE: - m_nScanBuffPtr POST: - m_nRestartRead - m_nRestartLastInd

// - m_nRestartLastInd
//
unsigned CimgDecode::BuffAddByte()
{
	unsigned nMarker = 0x00;
	unsigned nBuf0,nBuf1;

	// If we have already read in a restart marker but not
	// handled it yet, then simply return without reading any
	// more bytes
	if (m_bRestartRead) {
		return 0;
	}

	nBuf0 = m_pWBuf->Buf(m_nScanBuffPtr);
	nBuf1 = m_pWBuf->Buf(m_nScanBuffPtr+1);

	// Check for restart marker first. Assume none back-to-back.
	if (nBuf0 == 0xFF) {
		nMarker = nBuf1;

		if ((nMarker >= JFIF_RST0) && (nMarker <= JFIF_RST7)) {

			if (m_bVerbose) {
	  		  CString strTmp;
			  strTmp.Format(_T("  RESTART marker: @ 0x%08X.0 : RST%02u"),
				m_nScanBuffPtr,nMarker-JFIF_RST0);
			  m_pLog->AddLine(strTmp);
			}

			m_nRestartRead++;
			m_nRestartLastInd = nMarker - JFIF_RST0;
			if (m_nRestartLastInd != m_nRestartExpectInd) {
				if (!m_bScanErrorsDisable) {
	  				CString strTmp;
					strTmp.Format(_T("  ERROR: Expected RST marker index RST%u got RST%u @ 0x%08X.0"),
						m_nRestartExpectInd,m_nRestartLastInd,m_nScanBuffPtr);
					m_pLog->AddLineErr(strTmp);
				}
			}
			m_nRestartExpectInd = (m_nRestartLastInd+1)%8;

			// FIXME: Later on, we should be checking for RST out of sequence

			// END BUFFER READ HERE!
			// Indicate that a Restart marker has been seen, which
			// will prevent further reading of scan buffer until it
			// has been handled.
			m_bRestartRead = true;

			return 0;

/*
			// Now we need to skip to the next bytes
			m_nScanBuffPtr+=2;

			// Update local saved buffer vars
			nBuf0 = m_pWBuf->Buf(m_nScanBuffPtr);
			nBuf1 = m_pWBuf->Buf(m_nScanBuffPtr+1);