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// Boost CRC library crc.hpp header file -----------------------------------//
// Copyright 2001, 2004 Daryle Walker. Use, modification, and distribution are
// subject to the Boost Software License, Version 1.0. (See accompanying file
// LICENSE_1_0.txt or a copy at <http://www.boost.org/LICENSE_1_0.txt>.)
// See <http://www.boost.org/libs/crc/> for the library's home page.
#ifndef BOOST_CRC_HPP
#define BOOST_CRC_HPP
#include <boost/config.hpp> // for BOOST_STATIC_CONSTANT, etc.
#include <boost/integer.hpp> // for boost::uint_t
#include <climits> // for CHAR_BIT, etc.
#include <cstddef> // for std::size_t
#include <boost/limits.hpp> // for std::numeric_limits
// The type of CRC parameters that can go in a template should be related
// on the CRC's bit count. This macro expresses that type in a compact
// form, but also allows an alternate type for compilers that don't support
// dependent types (in template value-parameters).
#if !(defined(BOOST_NO_DEPENDENT_TYPES_IN_TEMPLATE_VALUE_PARAMETERS) || (defined(BOOST_MSVC) && (BOOST_MSVC <= 1300)))
#define BOOST_CRC_PARM_TYPE typename ::boost::uint_t<Bits>::fast
#else
#define BOOST_CRC_PARM_TYPE unsigned long
#endif
// Some compilers [MS VC++ 6] cannot correctly set up several versions of a
// function template unless every template argument can be unambiguously
// deduced from the function arguments. (The bug is hidden if only one version
// is needed.) Since all of the CRC function templates have this problem, the
// workaround is to make up a dummy function argument that encodes the template
// arguments. Calls to such template functions need all their template
// arguments explicitly specified. At least one compiler that needs this
// workaround also needs the default value for the dummy argument to be
// specified in the definition.
#if defined(__GNUC__) || !defined(BOOST_NO_EXPLICIT_FUNCTION_TEMPLATE_ARGUMENTS)
#define BOOST_CRC_DUMMY_PARM_TYPE
#define BOOST_CRC_DUMMY_INIT
#define BOOST_ACRC_DUMMY_PARM_TYPE
#define BOOST_ACRC_DUMMY_INIT
#else
namespace boost { namespace detail {
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly,
BOOST_CRC_PARM_TYPE InitRem, BOOST_CRC_PARM_TYPE FinalXor,
bool ReflectIn, bool ReflectRem >
struct dummy_crc_argument { };
} }
#define BOOST_CRC_DUMMY_PARM_TYPE , detail::dummy_crc_argument<Bits, \
TruncPoly, InitRem, FinalXor, ReflectIn, ReflectRem> *p_
#define BOOST_CRC_DUMMY_INIT BOOST_CRC_DUMMY_PARM_TYPE = 0
#define BOOST_ACRC_DUMMY_PARM_TYPE , detail::dummy_crc_argument<Bits, \
TruncPoly, 0, 0, false, false> *p_
#define BOOST_ACRC_DUMMY_INIT BOOST_ACRC_DUMMY_PARM_TYPE = 0
#endif
namespace boost
{
// Forward declarations ----------------------------------------------------//
template < std::size_t Bits >
class crc_basic;
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly = 0u,
BOOST_CRC_PARM_TYPE InitRem = 0u,
BOOST_CRC_PARM_TYPE FinalXor = 0u, bool ReflectIn = false,
bool ReflectRem = false >
class crc_optimal;
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly,
BOOST_CRC_PARM_TYPE InitRem, BOOST_CRC_PARM_TYPE FinalXor,
bool ReflectIn, bool ReflectRem >
typename uint_t<Bits>::fast crc( void const *buffer,
std::size_t byte_count
BOOST_CRC_DUMMY_PARM_TYPE );
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly >
typename uint_t<Bits>::fast augmented_crc( void const *buffer,
std::size_t byte_count, typename uint_t<Bits>::fast initial_remainder
BOOST_ACRC_DUMMY_PARM_TYPE );
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly >
typename uint_t<Bits>::fast augmented_crc( void const *buffer,
std::size_t byte_count
BOOST_ACRC_DUMMY_PARM_TYPE );
typedef crc_optimal<16, 0x8005, 0, 0, true, true> crc_16_type;
typedef crc_optimal<16, 0x1021, 0xFFFF, 0, false, false> crc_ccitt_type;
typedef crc_optimal<16, 0x8408, 0, 0, true, true> crc_xmodem_type;
typedef crc_optimal<32, 0x04C11DB7, 0xFFFFFFFF, 0xFFFFFFFF, true, true>
crc_32_type;
// Forward declarations for implementation detail stuff --------------------//
// (Just for the stuff that will be needed for the next two sections)
namespace detail
{
template < std::size_t Bits >
struct mask_uint_t;
template < >
struct mask_uint_t< std::numeric_limits<unsigned char>::digits >;
#if USHRT_MAX > UCHAR_MAX
template < >
struct mask_uint_t< std::numeric_limits<unsigned short>::digits >;
#endif
#if UINT_MAX > USHRT_MAX
template < >
struct mask_uint_t< std::numeric_limits<unsigned int>::digits >;
#endif
#if ULONG_MAX > UINT_MAX
template < >
struct mask_uint_t< std::numeric_limits<unsigned long>::digits >;
#endif
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly, bool Reflect >
struct crc_table_t;
template < std::size_t Bits, bool DoReflect >
class crc_helper;
#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
template < std::size_t Bits >
class crc_helper< Bits, false >;
#endif
} // namespace detail
// Simple cyclic redundancy code (CRC) class declaration -------------------//
template < std::size_t Bits >
class crc_basic
{
// Implementation type
typedef detail::mask_uint_t<Bits> masking_type;
public:
// Type
typedef typename masking_type::least value_type;
// Constant for the template parameter
BOOST_STATIC_CONSTANT( std::size_t, bit_count = Bits );
// Constructor
explicit crc_basic( value_type truncated_polynominal,
value_type initial_remainder = 0, value_type final_xor_value = 0,
bool reflect_input = false, bool reflect_remainder = false );
// Internal Operations
value_type get_truncated_polynominal() const;
value_type get_initial_remainder() const;
value_type get_final_xor_value() const;
bool get_reflect_input() const;
bool get_reflect_remainder() const;
value_type get_interim_remainder() const;
void reset( value_type new_rem );
void reset();
// External Operations
void process_bit( bool bit );
void process_bits( unsigned char bits, std::size_t bit_count );
void process_byte( unsigned char byte );
void process_block( void const *bytes_begin, void const *bytes_end );
void process_bytes( void const *buffer, std::size_t byte_count );
value_type checksum() const;
private:
// Member data
value_type rem_;
value_type poly_, init_, final_; // non-const to allow assignability
bool rft_in_, rft_out_; // non-const to allow assignability
}; // boost::crc_basic
// Optimized cyclic redundancy code (CRC) class declaration ----------------//
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly,
BOOST_CRC_PARM_TYPE InitRem, BOOST_CRC_PARM_TYPE FinalXor,
bool ReflectIn, bool ReflectRem >
class crc_optimal
{
// Implementation type
typedef detail::mask_uint_t<Bits> masking_type;
public:
// Type
typedef typename masking_type::fast value_type;
// Constants for the template parameters
BOOST_STATIC_CONSTANT( std::size_t, bit_count = Bits );
BOOST_STATIC_CONSTANT( value_type, truncated_polynominal = TruncPoly );
BOOST_STATIC_CONSTANT( value_type, initial_remainder = InitRem );
BOOST_STATIC_CONSTANT( value_type, final_xor_value = FinalXor );
BOOST_STATIC_CONSTANT( bool, reflect_input = ReflectIn );
BOOST_STATIC_CONSTANT( bool, reflect_remainder = ReflectRem );
// Constructor
explicit crc_optimal( value_type init_rem = InitRem );
// Internal Operations
value_type get_truncated_polynominal() const;
value_type get_initial_remainder() const;
value_type get_final_xor_value() const;
bool get_reflect_input() const;
bool get_reflect_remainder() const;
value_type get_interim_remainder() const;
void reset( value_type new_rem = InitRem );
// External Operations
void process_byte( unsigned char byte );
void process_block( void const *bytes_begin, void const *bytes_end );
void process_bytes( void const *buffer, std::size_t byte_count );
value_type checksum() const;
// Operators
void operator ()( unsigned char byte );
value_type operator ()() const;
private:
// The implementation of output reflection depends on both reflect states.
BOOST_STATIC_CONSTANT( bool, reflect_output = (ReflectRem != ReflectIn) );
#ifndef __BORLANDC__
#define BOOST_CRC_REF_OUT_VAL reflect_output
#else
typedef crc_optimal self_type;
#define BOOST_CRC_REF_OUT_VAL (self_type::reflect_output)
#endif
// More implementation types
typedef detail::crc_table_t<Bits, TruncPoly, ReflectIn> crc_table_type;
typedef detail::crc_helper<Bits, ReflectIn> helper_type;
typedef detail::crc_helper<Bits, BOOST_CRC_REF_OUT_VAL> reflect_out_type;
#undef BOOST_CRC_REF_OUT_VAL
// Member data
value_type rem_;
}; // boost::crc_optimal
// Implementation detail stuff ---------------------------------------------//
namespace detail
{
// Forward declarations for more implementation details
template < std::size_t Bits >
struct high_uint_t;
template < std::size_t Bits >
struct reflector;
// Traits class for mask; given the bit number
// (1-based), get the mask for that bit by itself.
template < std::size_t Bits >
struct high_uint_t
: boost::uint_t< Bits >
{
typedef boost::uint_t<Bits> base_type;
typedef typename base_type::least least;
typedef typename base_type::fast fast;
#if defined(__EDG_VERSION__) && __EDG_VERSION__ <= 243
static const least high_bit = 1ul << ( Bits - 1u );
static const fast high_bit_fast = 1ul << ( Bits - 1u );
#else
BOOST_STATIC_CONSTANT( least, high_bit = (least( 1u ) << ( Bits
- 1u )) );
BOOST_STATIC_CONSTANT( fast, high_bit_fast = (fast( 1u ) << ( Bits
- 1u )) );
#endif
}; // boost::detail::high_uint_t
// Reflection routine class wrapper
// (since MS VC++ 6 couldn't handle the unwrapped version)
template < std::size_t Bits >
struct reflector
{
typedef typename boost::uint_t<Bits>::fast value_type;
static value_type reflect( value_type x );
}; // boost::detail::reflector
// Function that reflects its argument
template < std::size_t Bits >
typename reflector<Bits>::value_type
reflector<Bits>::reflect
(
typename reflector<Bits>::value_type x
)
{
value_type reflection = 0;
value_type const one = 1;
for ( std::size_t i = 0 ; i < Bits ; ++i, x >>= 1 )
{
if ( x & one )
{
reflection |= ( one << (Bits - 1u - i) );
}
}
return reflection;
}
// Traits class for masks; given the bit number (1-based),
// get the mask for that bit and its lower bits.
template < std::size_t Bits >
struct mask_uint_t
: high_uint_t< Bits >
{
typedef high_uint_t<Bits> base_type;
typedef typename base_type::least least;
typedef typename base_type::fast fast;
#ifndef __BORLANDC__
using base_type::high_bit;
using base_type::high_bit_fast;
#else
BOOST_STATIC_CONSTANT( least, high_bit = base_type::high_bit );
BOOST_STATIC_CONSTANT( fast, high_bit_fast = base_type::high_bit_fast );
#endif
#if defined(__EDG_VERSION__) && __EDG_VERSION__ <= 243
static const least sig_bits = (~( ~( 0ul ) << Bits )) ;
#else
BOOST_STATIC_CONSTANT( least, sig_bits = (~( ~(least( 0u )) << Bits )) );
#endif
#if defined(__GNUC__) && __GNUC__ == 4 && __GNUC_MINOR__ == 0 && __GNUC_PATCHLEVEL__ == 2
// Work around a weird bug that ICEs the compiler in build_c_cast
BOOST_STATIC_CONSTANT( fast, sig_bits_fast = static_cast<fast>(sig_bits) );
#else
BOOST_STATIC_CONSTANT( fast, sig_bits_fast = fast(sig_bits) );
#endif
}; // boost::detail::mask_uint_t
template < >
struct mask_uint_t< std::numeric_limits<unsigned char>::digits >
: high_uint_t< std::numeric_limits<unsigned char>::digits >
{
typedef high_uint_t<std::numeric_limits<unsigned char>::digits>
base_type;
typedef base_type::least least;
typedef base_type::fast fast;
#ifndef __BORLANDC__
using base_type::high_bit;
using base_type::high_bit_fast;
#else
BOOST_STATIC_CONSTANT( least, high_bit = base_type::high_bit );
BOOST_STATIC_CONSTANT( fast, high_bit_fast = base_type::high_bit_fast );
#endif
BOOST_STATIC_CONSTANT( least, sig_bits = (~( least(0u) )) );
BOOST_STATIC_CONSTANT( fast, sig_bits_fast = fast(sig_bits) );
}; // boost::detail::mask_uint_t
#if USHRT_MAX > UCHAR_MAX
template < >
struct mask_uint_t< std::numeric_limits<unsigned short>::digits >
: high_uint_t< std::numeric_limits<unsigned short>::digits >
{
typedef high_uint_t<std::numeric_limits<unsigned short>::digits>
base_type;
typedef base_type::least least;
typedef base_type::fast fast;
#ifndef __BORLANDC__
using base_type::high_bit;
using base_type::high_bit_fast;
#else
BOOST_STATIC_CONSTANT( least, high_bit = base_type::high_bit );
BOOST_STATIC_CONSTANT( fast, high_bit_fast = base_type::high_bit_fast );
#endif
BOOST_STATIC_CONSTANT( least, sig_bits = (~( least(0u) )) );
BOOST_STATIC_CONSTANT( fast, sig_bits_fast = fast(sig_bits) );
}; // boost::detail::mask_uint_t
#endif
#if UINT_MAX > USHRT_MAX
template < >
struct mask_uint_t< std::numeric_limits<unsigned int>::digits >
: high_uint_t< std::numeric_limits<unsigned int>::digits >
{
typedef high_uint_t<std::numeric_limits<unsigned int>::digits>
base_type;
typedef base_type::least least;
typedef base_type::fast fast;
#ifndef __BORLANDC__
using base_type::high_bit;
using base_type::high_bit_fast;
#else
BOOST_STATIC_CONSTANT( least, high_bit = base_type::high_bit );
BOOST_STATIC_CONSTANT( fast, high_bit_fast = base_type::high_bit_fast );
#endif
BOOST_STATIC_CONSTANT( least, sig_bits = (~( least(0u) )) );
BOOST_STATIC_CONSTANT( fast, sig_bits_fast = fast(sig_bits) );
}; // boost::detail::mask_uint_t
#endif
#if ULONG_MAX > UINT_MAX
template < >
struct mask_uint_t< std::numeric_limits<unsigned long>::digits >
: high_uint_t< std::numeric_limits<unsigned long>::digits >
{
typedef high_uint_t<std::numeric_limits<unsigned long>::digits>
base_type;
typedef base_type::least least;
typedef base_type::fast fast;
#ifndef __BORLANDC__
using base_type::high_bit;
using base_type::high_bit_fast;
#else
BOOST_STATIC_CONSTANT( least, high_bit = base_type::high_bit );
BOOST_STATIC_CONSTANT( fast, high_bit_fast = base_type::high_bit_fast );
#endif
BOOST_STATIC_CONSTANT( least, sig_bits = (~( least(0u) )) );
BOOST_STATIC_CONSTANT( fast, sig_bits_fast = fast(sig_bits) );
}; // boost::detail::mask_uint_t
#endif
// CRC table generator
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly, bool Reflect >
struct crc_table_t
{
BOOST_STATIC_CONSTANT( std::size_t, byte_combos = (1ul << CHAR_BIT) );
typedef mask_uint_t<Bits> masking_type;
typedef typename masking_type::fast value_type;
#if defined(__BORLANDC__) && defined(_M_IX86) && (__BORLANDC__ == 0x560)
// for some reason Borland's command line compiler (version 0x560)
// chokes over this unless we do the calculation for it:
typedef value_type table_type[ 0x100 ];
#elif defined(__GNUC__)
// old versions of GCC (before 4.0.2) choke on using byte_combos
// as a constant expression when compiling with -pedantic.
typedef value_type table_type[1ul << CHAR_BIT];
#else
typedef value_type table_type[ byte_combos ];
#endif
static void init_table();
static table_type table_;
}; // boost::detail::crc_table_t
// CRC table generator static data member definition
// (Some compilers [Borland C++] require the initializer to be present.)
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly, bool Reflect >
typename crc_table_t<Bits, TruncPoly, Reflect>::table_type
crc_table_t<Bits, TruncPoly, Reflect>::table_
= { 0 };
// Populate CRC lookup table
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly, bool Reflect >
void
crc_table_t<Bits, TruncPoly, Reflect>::init_table
(
)
{
// compute table only on the first run
static bool did_init = false;
if ( did_init ) return;
// factor-out constants to avoid recalculation
value_type const fast_hi_bit = masking_type::high_bit_fast;
unsigned char const byte_hi_bit = 1u << (CHAR_BIT - 1u);
// loop over every possible dividend value
unsigned char dividend = 0;
do
{
value_type remainder = 0;
// go through all the dividend's bits
for ( unsigned char mask = byte_hi_bit ; mask ; mask >>= 1 )
{
// check if divisor fits
if ( dividend & mask )
{
remainder ^= fast_hi_bit;
}
// do polynominal division
if ( remainder & fast_hi_bit )
{
remainder <<= 1;
remainder ^= TruncPoly;
}
else
{
remainder <<= 1;
}
}
table_[ crc_helper<CHAR_BIT, Reflect>::reflect(dividend) ]
= crc_helper<Bits, Reflect>::reflect( remainder );
}
while ( ++dividend );
did_init = true;
}
#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
// Align the msb of the remainder to a byte
template < std::size_t Bits, bool RightShift >
class remainder
{
public:
typedef typename uint_t<Bits>::fast value_type;
static unsigned char align_msb( value_type rem )
{ return rem >> (Bits - CHAR_BIT); }
};
// Specialization for the case that the remainder has less
// bits than a byte: align the remainder msb to the byte msb
template < std::size_t Bits >
class remainder< Bits, false >
{
public:
typedef typename uint_t<Bits>::fast value_type;
static unsigned char align_msb( value_type rem )
{ return rem << (CHAR_BIT - Bits); }
};
#endif
// CRC helper routines
template < std::size_t Bits, bool DoReflect >
class crc_helper
{
public:
// Type
typedef typename uint_t<Bits>::fast value_type;
#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
// Possibly reflect a remainder
static value_type reflect( value_type x )
{ return detail::reflector<Bits>::reflect( x ); }
// Compare a byte to the remainder's highest byte
static unsigned char index( value_type rem, unsigned char x )
{ return x ^ rem; }
// Shift out the remainder's highest byte
static value_type shift( value_type rem )
{ return rem >> CHAR_BIT; }
#else
// Possibly reflect a remainder
static value_type reflect( value_type x )
{ return DoReflect ? detail::reflector<Bits>::reflect( x ) : x; }
// Compare a byte to the remainder's highest byte
static unsigned char index( value_type rem, unsigned char x )
{ return x ^ ( DoReflect ? rem :
((Bits>CHAR_BIT)?( rem >> (Bits - CHAR_BIT) ) :
( rem << (CHAR_BIT - Bits) ))); }
// Shift out the remainder's highest byte
static value_type shift( value_type rem )
{ return DoReflect ? rem >> CHAR_BIT : rem << CHAR_BIT; }
#endif
}; // boost::detail::crc_helper
#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
template < std::size_t Bits >
class crc_helper<Bits, false>
{
public:
// Type
typedef typename uint_t<Bits>::fast value_type;
// Possibly reflect a remainder
static value_type reflect( value_type x )
{ return x; }
// Compare a byte to the remainder's highest byte
static unsigned char index( value_type rem, unsigned char x )
{ return x ^ remainder<Bits,(Bits>CHAR_BIT)>::align_msb( rem ); }
// Shift out the remainder's highest byte
static value_type shift( value_type rem )
{ return rem << CHAR_BIT; }
}; // boost::detail::crc_helper
#endif
} // namespace detail
// Simple CRC class function definitions -----------------------------------//
template < std::size_t Bits >
inline
crc_basic<Bits>::crc_basic
(
typename crc_basic<Bits>::value_type truncated_polynominal,
typename crc_basic<Bits>::value_type initial_remainder, // = 0
typename crc_basic<Bits>::value_type final_xor_value, // = 0
bool reflect_input, // = false
bool reflect_remainder // = false
)
: rem_( initial_remainder ), poly_( truncated_polynominal )
, init_( initial_remainder ), final_( final_xor_value )
, rft_in_( reflect_input ), rft_out_( reflect_remainder )
{
}
template < std::size_t Bits >
inline
typename crc_basic<Bits>::value_type
crc_basic<Bits>::get_truncated_polynominal
(
) const
{
return poly_;
}
template < std::size_t Bits >
inline
typename crc_basic<Bits>::value_type
crc_basic<Bits>::get_initial_remainder
(
) const
{
return init_;
}
template < std::size_t Bits >
inline
typename crc_basic<Bits>::value_type
crc_basic<Bits>::get_final_xor_value
(
) const
{
return final_;
}
template < std::size_t Bits >
inline
bool
crc_basic<Bits>::get_reflect_input
(
) const
{
return rft_in_;
}
template < std::size_t Bits >
inline
bool
crc_basic<Bits>::get_reflect_remainder
(
) const
{
return rft_out_;
}
template < std::size_t Bits >
inline
typename crc_basic<Bits>::value_type
crc_basic<Bits>::get_interim_remainder
(
) const
{
return rem_ & masking_type::sig_bits;
}
template < std::size_t Bits >
inline
void
crc_basic<Bits>::reset
(
typename crc_basic<Bits>::value_type new_rem
)
{
rem_ = new_rem;
}
template < std::size_t Bits >
inline
void
crc_basic<Bits>::reset
(
)
{
this->reset( this->get_initial_remainder() );
}
template < std::size_t Bits >
inline
void
crc_basic<Bits>::process_bit
(
bool bit
)
{
value_type const high_bit_mask = masking_type::high_bit;
// compare the new bit with the remainder's highest
rem_ ^= ( bit ? high_bit_mask : 0u );
// a full polynominal division step is done when the highest bit is one
bool const do_poly_div = static_cast<bool>( rem_ & high_bit_mask );
// shift out the highest bit
rem_ <<= 1;
// carry out the division, if needed
if ( do_poly_div )
{
rem_ ^= poly_;
}
}
template < std::size_t Bits >
void
crc_basic<Bits>::process_bits
(
unsigned char bits,
std::size_t bit_count
)
{
// ignore the bits above the ones we want
bits <<= CHAR_BIT - bit_count;
// compute the CRC for each bit, starting with the upper ones
unsigned char const high_bit_mask = 1u << ( CHAR_BIT - 1u );
for ( std::size_t i = bit_count ; i > 0u ; --i, bits <<= 1u )
{
process_bit( static_cast<bool>(bits & high_bit_mask) );
}
}
template < std::size_t Bits >
inline
void
crc_basic<Bits>::process_byte
(
unsigned char byte
)
{
process_bits( (rft_in_ ? detail::reflector<CHAR_BIT>::reflect(byte)
: byte), CHAR_BIT );
}
template < std::size_t Bits >
void
crc_basic<Bits>::process_block
(
void const * bytes_begin,
void const * bytes_end
)
{
for ( unsigned char const * p
= static_cast<unsigned char const *>(bytes_begin) ; p < bytes_end ; ++p )
{
process_byte( *p );
}
}
template < std::size_t Bits >
inline
void
crc_basic<Bits>::process_bytes
(
void const * buffer,
std::size_t byte_count
)
{
unsigned char const * const b = static_cast<unsigned char const *>(
buffer );
process_block( b, b + byte_count );
}
template < std::size_t Bits >
inline
typename crc_basic<Bits>::value_type
crc_basic<Bits>::checksum
(
) const
{
return ( (rft_out_ ? detail::reflector<Bits>::reflect( rem_ ) : rem_)
^ final_ ) & masking_type::sig_bits;
}
// Optimized CRC class function definitions --------------------------------//
// Macro to compact code
#define BOOST_CRC_OPTIMAL_NAME crc_optimal<Bits, TruncPoly, InitRem, \
FinalXor, ReflectIn, ReflectRem>
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly,
BOOST_CRC_PARM_TYPE InitRem, BOOST_CRC_PARM_TYPE FinalXor,
bool ReflectIn, bool ReflectRem >
inline
BOOST_CRC_OPTIMAL_NAME::crc_optimal
(
typename BOOST_CRC_OPTIMAL_NAME::value_type init_rem // = InitRem
)
: rem_( helper_type::reflect(init_rem) )
{
crc_table_type::init_table();
}
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly,
BOOST_CRC_PARM_TYPE InitRem, BOOST_CRC_PARM_TYPE FinalXor,
bool ReflectIn, bool ReflectRem >
inline
typename BOOST_CRC_OPTIMAL_NAME::value_type
BOOST_CRC_OPTIMAL_NAME::get_truncated_polynominal
(
) const
{
return TruncPoly;
}
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly,
BOOST_CRC_PARM_TYPE InitRem, BOOST_CRC_PARM_TYPE FinalXor,
bool ReflectIn, bool ReflectRem >
inline
typename BOOST_CRC_OPTIMAL_NAME::value_type
BOOST_CRC_OPTIMAL_NAME::get_initial_remainder
(
) const
{
return InitRem;
}
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly,
BOOST_CRC_PARM_TYPE InitRem, BOOST_CRC_PARM_TYPE FinalXor,
bool ReflectIn, bool ReflectRem >
inline
typename BOOST_CRC_OPTIMAL_NAME::value_type
BOOST_CRC_OPTIMAL_NAME::get_final_xor_value
(
) const
{
return FinalXor;
}
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly,
BOOST_CRC_PARM_TYPE InitRem, BOOST_CRC_PARM_TYPE FinalXor,
bool ReflectIn, bool ReflectRem >
inline
bool
BOOST_CRC_OPTIMAL_NAME::get_reflect_input
(
) const
{
return ReflectIn;
}
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly,
BOOST_CRC_PARM_TYPE InitRem, BOOST_CRC_PARM_TYPE FinalXor,
bool ReflectIn, bool ReflectRem >
inline
bool
BOOST_CRC_OPTIMAL_NAME::get_reflect_remainder
(
) const
{
return ReflectRem;
}
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly,
BOOST_CRC_PARM_TYPE InitRem, BOOST_CRC_PARM_TYPE FinalXor,
bool ReflectIn, bool ReflectRem >
inline
typename BOOST_CRC_OPTIMAL_NAME::value_type
BOOST_CRC_OPTIMAL_NAME::get_interim_remainder
(
) const
{
// Interim remainder should be _un_-reflected, so we have to undo it.
return helper_type::reflect( rem_ ) & masking_type::sig_bits_fast;
}
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly,
BOOST_CRC_PARM_TYPE InitRem, BOOST_CRC_PARM_TYPE FinalXor,
bool ReflectIn, bool ReflectRem >
inline
void
BOOST_CRC_OPTIMAL_NAME::reset
(
typename BOOST_CRC_OPTIMAL_NAME::value_type new_rem // = InitRem
)
{
rem_ = helper_type::reflect( new_rem );
}
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly,
BOOST_CRC_PARM_TYPE InitRem, BOOST_CRC_PARM_TYPE FinalXor,
bool ReflectIn, bool ReflectRem >
inline
void
BOOST_CRC_OPTIMAL_NAME::process_byte
(
unsigned char byte
)
{
process_bytes( &byte, sizeof(byte) );
}
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly,
BOOST_CRC_PARM_TYPE InitRem, BOOST_CRC_PARM_TYPE FinalXor,
bool ReflectIn, bool ReflectRem >
void
BOOST_CRC_OPTIMAL_NAME::process_block
(
void const * bytes_begin,
void const * bytes_end
)
{
// Recompute the CRC for each byte passed
for ( unsigned char const * p
= static_cast<unsigned char const *>(bytes_begin) ; p < bytes_end ; ++p )
{
// Compare the new byte with the remainder's higher bits to
// get the new bits, shift out the remainder's current higher
// bits, and update the remainder with the polynominal division
// of the new bits.
unsigned char const byte_index = helper_type::index( rem_, *p );
rem_ = helper_type::shift( rem_ );
rem_ ^= crc_table_type::table_[ byte_index ];
}
}
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly,
BOOST_CRC_PARM_TYPE InitRem, BOOST_CRC_PARM_TYPE FinalXor,
bool ReflectIn, bool ReflectRem >
inline
void
BOOST_CRC_OPTIMAL_NAME::process_bytes
(
void const * buffer,
std::size_t byte_count
)
{
unsigned char const * const b = static_cast<unsigned char const *>(
buffer );
process_block( b, b + byte_count );
}
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly,
BOOST_CRC_PARM_TYPE InitRem, BOOST_CRC_PARM_TYPE FinalXor,
bool ReflectIn, bool ReflectRem >
inline
typename BOOST_CRC_OPTIMAL_NAME::value_type
BOOST_CRC_OPTIMAL_NAME::checksum
(
) const
{
return ( reflect_out_type::reflect(rem_) ^ get_final_xor_value() )
& masking_type::sig_bits_fast;
}
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly,
BOOST_CRC_PARM_TYPE InitRem, BOOST_CRC_PARM_TYPE FinalXor,
bool ReflectIn, bool ReflectRem >
inline
void
BOOST_CRC_OPTIMAL_NAME::operator ()
(
unsigned char byte
)
{
process_byte( byte );
}
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly,
BOOST_CRC_PARM_TYPE InitRem, BOOST_CRC_PARM_TYPE FinalXor,
bool ReflectIn, bool ReflectRem >
inline
typename BOOST_CRC_OPTIMAL_NAME::value_type
BOOST_CRC_OPTIMAL_NAME::operator ()
(
) const
{
return checksum();
}
// CRC computation function definition -------------------------------------//
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly,
BOOST_CRC_PARM_TYPE InitRem, BOOST_CRC_PARM_TYPE FinalXor,
bool ReflectIn, bool ReflectRem >
inline
typename uint_t<Bits>::fast
crc
(
void const * buffer,
std::size_t byte_count
BOOST_CRC_DUMMY_INIT
)
{
BOOST_CRC_OPTIMAL_NAME computer;
computer.process_bytes( buffer, byte_count );
return computer.checksum();
}
// Augmented-message CRC computation function definitions ------------------//
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly >
typename uint_t<Bits>::fast
augmented_crc
(
void const * buffer,
std::size_t byte_count,
typename uint_t<Bits>::fast initial_remainder
BOOST_ACRC_DUMMY_INIT
)
{
typedef unsigned char byte_type;
typedef detail::mask_uint_t<Bits> masking_type;
typedef detail::crc_table_t<Bits, TruncPoly, false> crc_table_type;
typename masking_type::fast rem = initial_remainder;
byte_type const * const b = static_cast<byte_type const *>( buffer );
byte_type const * const e = b + byte_count;
crc_table_type::init_table();
for ( byte_type const * p = b ; p < e ; ++p )
{
// Use the current top byte as the table index to the next
// "partial product." Shift out that top byte, shifting in
// the next augmented-message byte. Complete the division.
byte_type const byte_index = rem >> ( Bits - CHAR_BIT );
rem <<= CHAR_BIT;
rem |= *p;
rem ^= crc_table_type::table_[ byte_index ];
}
return rem & masking_type::sig_bits_fast;
}
template < std::size_t Bits, BOOST_CRC_PARM_TYPE TruncPoly >
inline
typename uint_t<Bits>::fast
augmented_crc
(
void const * buffer,
std::size_t byte_count
BOOST_ACRC_DUMMY_INIT
)
{
// The last function argument has its type specified so the other version of
// augmented_crc will be called. If the cast wasn't in place, and the
// BOOST_ACRC_DUMMY_INIT added a third argument (for a workaround), the "0"
// would match as that third argument, leading to infinite recursion.
return augmented_crc<Bits, TruncPoly>( buffer, byte_count,
static_cast<typename uint_t<Bits>::fast>(0) );
}
} // namespace boost
// Undo header-private macros
#undef BOOST_CRC_OPTIMAL_NAME
#undef BOOST_ACRC_DUMMY_INIT
#undef BOOST_ACRC_DUMMY_PARM_TYPE
#undef BOOST_CRC_DUMMY_INIT
#undef BOOST_CRC_DUMMY_PARM_TYPE
#undef BOOST_CRC_PARM_TYPE
#endif // BOOST_CRC_HPP
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