completed BitReader class; small improvements
This commit is contained in:
parent
b6355ac01b
commit
6bf736af0e
|
@ -127,8 +127,7 @@ string BinaryReader::readString(size_t length)
|
||||||
{
|
{
|
||||||
unique_ptr<char []> buff = make_unique<char []>(length);
|
unique_ptr<char []> buff = make_unique<char []>(length);
|
||||||
m_stream->read(buff.get(), length);
|
m_stream->read(buff.get(), length);
|
||||||
string res(buff.get(), length);
|
return string(buff.get(), length);
|
||||||
return res;
|
|
||||||
}
|
}
|
||||||
|
|
||||||
/*!
|
/*!
|
||||||
|
|
|
@ -1,15 +1,82 @@
|
||||||
#ifndef IOUTILITIES_BITREADER_H
|
#ifndef IOUTILITIES_BITREADER_H
|
||||||
#define IOUTILITIES_BITREADER_H
|
#define IOUTILITIES_BITREADER_H
|
||||||
|
|
||||||
|
#include "../conversion/types.h"
|
||||||
|
#include "../application/global.h"
|
||||||
|
|
||||||
|
#include <ios>
|
||||||
|
|
||||||
namespace IoUtilities {
|
namespace IoUtilities {
|
||||||
|
|
||||||
class BitReader
|
class LIB_EXPORT BitReader
|
||||||
{
|
{
|
||||||
public:
|
public:
|
||||||
BitReader();
|
BitReader(const char *buffer, std::size_t bufferSize);
|
||||||
|
BitReader(const char *buffer, const char *end);
|
||||||
|
|
||||||
|
template<typename intType> intType readBits(byte bitCount);
|
||||||
|
void skipBits(std::size_t bitCount);
|
||||||
|
std::size_t bitsAvailable();
|
||||||
|
|
||||||
|
private:
|
||||||
|
const byte *m_buffer;
|
||||||
|
const byte *m_end;
|
||||||
|
byte m_bitsAvail;
|
||||||
};
|
};
|
||||||
|
|
||||||
|
/*!
|
||||||
|
* \brief Constructs a new BitReader.
|
||||||
|
* \remarks Does not destroy the specified \a buffer.
|
||||||
|
*/
|
||||||
|
inline BitReader::BitReader(const char *buffer, std::size_t bufferSize) :
|
||||||
|
m_buffer(reinterpret_cast<const byte *>(buffer)),
|
||||||
|
m_end(reinterpret_cast<const byte *>(buffer + bufferSize)),
|
||||||
|
m_bitsAvail(8)
|
||||||
|
{}
|
||||||
|
|
||||||
|
/*!
|
||||||
|
* \brief Constructs a new BitReader.
|
||||||
|
* \remarks Does not destroy the specified \a buffer.
|
||||||
|
*/
|
||||||
|
inline BitReader::BitReader(const char *buffer, const char *end) :
|
||||||
|
m_buffer(reinterpret_cast<const byte *>(buffer)),
|
||||||
|
m_end(reinterpret_cast<const byte *>(end)),
|
||||||
|
m_bitsAvail(8)
|
||||||
|
{}
|
||||||
|
|
||||||
|
/*!
|
||||||
|
* \brief Reads the specified number of bits from the buffer.
|
||||||
|
* \param bitCount Specifies the number of bits read.
|
||||||
|
* \tparam intType Specifies the return value type.
|
||||||
|
* \remarks Does not check whether intType is big enough to hold result.
|
||||||
|
* \throws Throws ios_base::failure if the end of the buffer is exceeded.
|
||||||
|
* The reader becomes invalid in that case.
|
||||||
|
*/
|
||||||
|
template<typename intType>
|
||||||
|
intType BitReader::readBits(byte bitCount)
|
||||||
|
{
|
||||||
|
intType val = 0;
|
||||||
|
for(byte readAtOnce; bitCount; bitCount -= readAtOnce) {
|
||||||
|
readAtOnce = std::min(bitCount, m_bitsAvail);
|
||||||
|
val = (val << readAtOnce) | (((*m_buffer) >> (m_bitsAvail -= readAtOnce)) & (0xFF >> (0x08 - readAtOnce)));
|
||||||
|
if(!m_bitsAvail) {
|
||||||
|
m_bitsAvail = 8;
|
||||||
|
if(++m_buffer >= m_end) {
|
||||||
|
throw std::ios_base::failure("end of buffer exceeded");
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
return val;
|
||||||
|
}
|
||||||
|
|
||||||
|
/*!
|
||||||
|
* \brief Returns the number of bits which are still available to read.
|
||||||
|
*/
|
||||||
|
inline std::size_t BitReader::bitsAvailable()
|
||||||
|
{
|
||||||
|
return ((m_end - m_buffer) * 8) + m_bitsAvail;
|
||||||
|
}
|
||||||
|
|
||||||
} // namespace IoUtilities
|
} // namespace IoUtilities
|
||||||
|
|
||||||
#endif // IOUTILITIES_BITREADER_H
|
#endif // IOUTILITIES_BITREADER_H
|
||||||
|
|
Loading…
Reference in New Issue