Method getCode

lib/YAWidgets/src/LzwDecoder.cpp:337–382

}

bool LzwDecoder::getCode(uint32_t& code, const ReadFromInStream& readFromInStreamFunc)
{
    bool     isSuccessful   = true;
    uint32_t codeBitsNeeded = m_codeWidth;

    code                    = 0U;

    /* Run as long as code bits are still needed. */
    while ((0U < codeBitsNeeded) && (true == isSuccessful))
    {
        /* No bits in the buffer anymore? */
        if (0U == m_bitsInBuffer)
        {
            uint8_t data = 0U;

            /* Read data from code stream. */
            if (false == readFromInStreamFunc(data))
            {
                /* No more data is available, abort now. */
                isSuccessful = false;
            }
            else
            {
                m_codeBuffer   = data;
                m_bitsInBuffer = 8U;
            }
        }

        if (true == isSuccessful)
        {
            uint32_t bitsAvailable   = (m_bitsInBuffer < codeBitsNeeded) ? m_bitsInBuffer : codeBitsNeeded;
            uint32_t mask            = (1U << bitsAvailable) - 1U; /* Mask for n bits. */

            code                    |= (m_codeBuffer & mask) << (m_codeWidth - codeBitsNeeded);

            /* Remove bits from code buffer. */
            m_codeBuffer           >>= bitsAvailable;
            m_bitsInBuffer          -= bitsAvailable;

            /* Now less bits are needed. */
            codeBitsNeeded          -= bitsAvailable;
        }
    }

    return isSuccessful;
}

bool LzwDecoder::decompress(uint32_t code, const WriteToOutStream& writeToOutStreamFunc)
{