ceph/src/boost/libs/numeric/interval/include/boost/numeric/interval/detail/c99sub_rounding_control.hpp

   1 /* Boost interval/detail/c99sub_rounding_control.hpp file
   2  *
   3  * Copyright 2000 Jens Maurer
   4  * Copyright 2002 Hervé Brönnimann, Guillaume Melquiond, Sylvain Pion
   5  *
   6  * Distributed under the Boost Software License, Version 1.0.
   7  * (See accompanying file LICENSE_1_0.txt or
   8  * copy at http://www.boost.org/LICENSE_1_0.txt)
   9  */
  10
  11 #ifndef BOOST_NUMERIC_INTERVAL_DETAIL_C99SUB_ROUNDING_CONTROL_HPP
  12 #define BOOST_NUMERIC_INTERVAL_DETAIL_C99SUB_ROUNDING_CONTROL_HPP
  13
  14 #include <boost/detail/fenv.hpp>      // ISO C 99 rounding mode control
  15
  16 namespace boost {
  17 namespace numeric {
  18 namespace interval_lib {
  19 namespace detail {
  20
  21 extern "C" { double rint(double); }
  22
  23 struct c99_rounding_control
  24 {
  25   typedef int rounding_mode;
  26
  27   static void set_rounding_mode(rounding_mode mode)  { fesetround(mode); }
  28   static void get_rounding_mode(rounding_mode &mode) { mode = fegetround(); }
  29   static void downward()    { set_rounding_mode(FE_DOWNWARD);   }
  30   static void upward()      { set_rounding_mode(FE_UPWARD);     }
  31   static void to_nearest()  { set_rounding_mode(FE_TONEAREST);  }
  32   static void toward_zero() { set_rounding_mode(FE_TOWARDZERO); }
  33
  34   template<class T>
  35   static T to_int(const T& r) { return rint(r); }
  36 };
  37
  38 } // namespace detail
  39 } // namespace interval_lib
  40 } // namespace numeric
  41 } // namespace boost
  42
  43 #endif // BOOST_NUMERIC_INTERVAL_DETAIL_C99SUB_ROUBDING_CONTROL_HPP