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authorAnas Nashif <anas.nashif@intel.com>2012-10-30 12:57:26 -0700
committerAnas Nashif <anas.nashif@intel.com>2012-10-30 12:57:26 -0700
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treed3765a80e7d3b9640ec2e930743630cd6b9fce2b /boost/crc.hpp
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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
+