ceph/src/boost/libs/integer/include/boost/integer/integer_mask.hpp

   1 //  Boost integer/integer_mask.hpp header file  ------------------------------//
   2
   3 //  (C) Copyright Daryle Walker 2001.
   4 //  Distributed under the Boost Software License, Version 1.0. (See
   5 //  accompanying file LICENSE_1_0.txt or copy at
   6 //  http://www.boost.org/LICENSE_1_0.txt)
   7
   8 //  See http://www.boost.org for updates, documentation, and revision history.
   9
  10 #ifndef BOOST_INTEGER_INTEGER_MASK_HPP
  11 #define BOOST_INTEGER_INTEGER_MASK_HPP
  12
  13 #include <boost/integer_fwd.hpp>  // self include
  14
  15 #include <boost/config.hpp>   // for BOOST_STATIC_CONSTANT
  16 #include <boost/integer.hpp>  // for boost::uint_t
  17
  18 #include <climits>  // for UCHAR_MAX, etc.
  19 #include <cstddef>  // for std::size_t
  20
  21 #include <boost/limits.hpp>  // for std::numeric_limits
  22
  23 //
  24 // We simply cannot include this header on gcc without getting copious warnings of the kind:
  25 //
  26 // boost/integer/integer_mask.hpp:93:35: warning: use of C99 long long integer constant
  27 //
  28 // And yet there is no other reasonable implementation, so we declare this a system header
  29 // to suppress these warnings.
  30 //
  31 #if defined(__GNUC__) && (__GNUC__ >= 4)
  32 #pragma GCC system_header
  33 #endif
  34
  35 namespace boost
  36 {
  37
  38
  39 //  Specified single-bit mask class declaration  -----------------------------//
  40 //  (Lowest bit starts counting at 0.)
  41
  42 template < std::size_t Bit >
  43 struct high_bit_mask_t
  44 {
  45     typedef typename uint_t<(Bit + 1)>::least  least;
  46     typedef typename uint_t<(Bit + 1)>::fast   fast;
  47
  48     BOOST_STATIC_CONSTANT( least, high_bit = (least( 1u ) << Bit) );
  49     BOOST_STATIC_CONSTANT( fast, high_bit_fast = (fast( 1u ) << Bit) );
  50
  51     BOOST_STATIC_CONSTANT( std::size_t, bit_position = Bit );
  52
  53 };  // boost::high_bit_mask_t
  54
  55
  56 //  Specified bit-block mask class declaration  ------------------------------//
  57 //  Makes masks for the lowest N bits
  58 //  (Specializations are needed when N fills up a type.)
  59
  60 template < std::size_t Bits >
  61 struct low_bits_mask_t
  62 {
  63     typedef typename uint_t<Bits>::least  least;
  64     typedef typename uint_t<Bits>::fast   fast;
  65
  66     BOOST_STATIC_CONSTANT( least, sig_bits = (~( ~(least( 0u )) << Bits )) );
  67     BOOST_STATIC_CONSTANT( fast, sig_bits_fast = fast(sig_bits) );
  68
  69     BOOST_STATIC_CONSTANT( std::size_t, bit_count = Bits );
  70
  71 };  // boost::low_bits_mask_t
  72
  73
  74 #define BOOST_LOW_BITS_MASK_SPECIALIZE( Type )                                  \
  75   template <  >  struct low_bits_mask_t< std::numeric_limits<Type>::digits >  { \
  76       typedef std::numeric_limits<Type>           limits_type;                  \
  77       typedef uint_t<limits_type::digits>::least  least;                        \
  78       typedef uint_t<limits_type::digits>::fast   fast;                         \
  79       BOOST_STATIC_CONSTANT( least, sig_bits = (~( least(0u) )) );              \
  80       BOOST_STATIC_CONSTANT( fast, sig_bits_fast = fast(sig_bits) );            \
  81       BOOST_STATIC_CONSTANT( std::size_t, bit_count = limits_type::digits );    \
  82   }
  83
  84 #ifdef BOOST_MSVC
  85 #pragma warning(push)
  86 #pragma warning(disable:4245)  // 'initializing' : conversion from 'int' to 'const boost::low_bits_mask_t<8>::least', signed/unsigned mismatch
  87 #endif
  88
  89 BOOST_LOW_BITS_MASK_SPECIALIZE( unsigned char );
  90
  91 #if USHRT_MAX > UCHAR_MAX
  92 BOOST_LOW_BITS_MASK_SPECIALIZE( unsigned short );
  93 #endif
  94
  95 #if UINT_MAX > USHRT_MAX
  96 BOOST_LOW_BITS_MASK_SPECIALIZE( unsigned int );
  97 #endif
  98
  99 #if ULONG_MAX > UINT_MAX
 100 BOOST_LOW_BITS_MASK_SPECIALIZE( unsigned long );
 101 #endif
 102
 103 #if defined(BOOST_HAS_LONG_LONG)
 104     #if ((defined(ULLONG_MAX) && (ULLONG_MAX > ULONG_MAX)) ||\
 105         (defined(ULONG_LONG_MAX) && (ULONG_LONG_MAX > ULONG_MAX)) ||\
 106         (defined(ULONGLONG_MAX) && (ULONGLONG_MAX > ULONG_MAX)) ||\
 107         (defined(_ULLONG_MAX) && (_ULLONG_MAX > ULONG_MAX)))
 108     BOOST_LOW_BITS_MASK_SPECIALIZE( boost::ulong_long_type );
 109     #endif
 110 #elif defined(BOOST_HAS_MS_INT64)
 111     #if 18446744073709551615ui64 > ULONG_MAX
 112     BOOST_LOW_BITS_MASK_SPECIALIZE( unsigned __int64 );
 113     #endif
 114 #endif
 115
 116 #ifdef BOOST_MSVC
 117 #pragma warning(pop)
 118 #endif
 119
 120 #undef BOOST_LOW_BITS_MASK_SPECIALIZE
 121
 122
 123 }  // namespace boost
 124
 125
 126 #endif  // BOOST_INTEGER_INTEGER_MASK_HPP