feedc0de/boost_integer
1
0
Fork 0
forked from boostorg/integer
Code Pull Requests Activity

Added daryle's missing files

Browse Source 
[SVN r11971]
This commit is contained in:
Dave Abrahams
2001-12-07 12:48:20 +00:00
parent 5477a9641c
commit c50993d5d4
3 changed files with 240 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

93
include/boost/integer/integer_mask.hpp Normal file
View File

@ -0,0 +1,93 @@
// Boost integer/integer_mask.hpp header file ------------------------------//
// (C) Copyright Daryle Walker 2001. Permission to copy, use, modify, sell and
// distribute this software is granted provided this copyright notice appears
// in all copies. This software is provided "as is" without express or
// implied warranty, and with no claim as to its suitability for any purpose.
// See http://www.boost.org for updates, documentation, and revision history.
#ifndef BOOST_INTEGER_INTEGER_MASK_HPP
#define BOOST_INTEGER_INTEGER_MASK_HPP
#include <boost/integer_fwd.hpp> // self include
#include <boost/config.hpp> // for BOOST_STATIC_CONSTANT
#include <boost/integer.hpp> // for boost::uint_t
#include <climits> // for UCHAR_MAX, etc.
#include <cstddef> // for std::size_t
#include <boost/limits.hpp> // for std::numeric_limits
namespace boost
{
// Specified single-bit mask class declaration -----------------------------//
// (Lowest bit starts counting at 0.)
template < std::size_t Bit >
struct high_bit_mask_t
{
typedef typename uint_t<(Bit + 1)>::least least;
typedef typename uint_t<(Bit + 1)>::fast fast;
BOOST_STATIC_CONSTANT( least, high_bit = (least( 1u ) << Bit) );
BOOST_STATIC_CONSTANT( fast, high_bit_fast = (fast( 1u ) << Bit) );
BOOST_STATIC_CONSTANT( std::size_t, bit_position = Bit );
}; // boost::high_bit_mask_t
// Specified bit-block mask class declaration ------------------------------//
// Makes masks for the lowest N bits
// (Specializations are needed when N fills up a type.)
template < std::size_t Bits >
struct low_bits_mask_t
{
typedef typename uint_t<Bits>::least least;
typedef typename uint_t<Bits>::fast fast;
BOOST_STATIC_CONSTANT( least, sig_bits = (~( ~(least( 0u )) << Bits )) );
BOOST_STATIC_CONSTANT( fast, sig_bits_fast = fast(sig_bits) );
BOOST_STATIC_CONSTANT( std::size_t, bit_count = Bits );
}; // boost::low_bits_mask_t
#define BOOST_LOW_BITS_MASK_SPECIALIZE( Type ) \
template < > struct low_bits_mask_t< std::numeric_limits<Type>::digits > { \
typedef std::numeric_limits<Type> limits_type; \
typedef uint_t<limits_type::digits>::least least; \
typedef uint_t<limits_type::digits>::fast fast; \
BOOST_STATIC_CONSTANT( least, sig_bits = (~( least(0u) )) ); \
BOOST_STATIC_CONSTANT( fast, sig_bits_fast = fast(sig_bits) ); \
BOOST_STATIC_CONSTANT( std::size_t, bit_count = limits_type::digits ); \
}
BOOST_LOW_BITS_MASK_SPECIALIZE( unsigned char );
#if USHRT_MAX > UCHAR_MAX
BOOST_LOW_BITS_MASK_SPECIALIZE( unsigned short );
#endif
#if UINT_MAX > USHRT_MAX
BOOST_LOW_BITS_MASK_SPECIALIZE( unsigned int );
#endif
#if ULONG_MAX > UINT_MAX
BOOST_LOW_BITS_MASK_SPECIALIZE( unsigned long );
#endif
#undef BOOST_LOW_BITS_MASK_SPECIALIZE
} // namespace boost
#endif // BOOST_INTEGER_INTEGER_MASK_HPP