Collaboration diagram for LVL1BS::PpmByteStreamReadV1V2Tool::BitReader:

Public Member Functions
	BitReader (const std::vector< uint32_t > &ppBlock)

uint32_t	getField (const uint8_t numBits)

Private Attributes
uint32_t	m_ppPointer

uint32_t	m_ppMaxBit

const std::vector< uint32_t > &	m_ppBlock

Detailed Description

Definition at line 81 of file PpmByteStreamReadV1V2Tool.h.

Constructor & Destructor Documentation

◆ BitReader()

LVL1BS::PpmByteStreamReadV1V2Tool::BitReader::BitReader ( const std::vector< uint32_t > & ppBlock )

inline

Definition at line 84 of file PpmByteStreamReadV1V2Tool.h.

       : m_ppPointer (0),
         m_ppMaxBit (31 * ppBlock.size()),
         m_ppBlock (ppBlock)
     {
     }

Member Function Documentation

◆ getField()

uint32_t LVL1BS::PpmByteStreamReadV1V2Tool::BitReader::getField ( const uint8_t numBits )

Definition at line 1091 of file PpmByteStreamReadV1V2Tool.cxx.

 {
   if ((m_ppPointer + numBits) <= m_ppMaxBit) {
     uint32_t iWord = m_ppPointer / 31;
     uint8_t iBit = m_ppPointer % 31;
     m_ppPointer += numBits;
  
     uint32_t result;
     if ((iBit + numBits) <= 31) {
       result = ::bitFieldSize(m_ppBlock[iWord], iBit, numBits);
     } else {
       uint8_t nb1 = 31 - iBit;
       uint8_t nb2 = numBits - nb1;
       uint32_t field1 = ::bitFieldSize(m_ppBlock[iWord], iBit, nb1);
       uint32_t field2 = ::bitFieldSize(m_ppBlock[iWord + 1], 0, nb2);
       result = field1 | (field2 << nb1);
     }
  
     return result;
   }
  
   throw std::out_of_range("Requested too much bits from ppm block");
 }