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boost/chrono/io/ios_base_state.hpp

//  (C) Copyright 2011 Vicente J. Botet Escriba
//  Use, modification and distribution are subject to the Boost Software License,
//  Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
//  http://www.boost.org/LICENSE_1_0.txt).
//
// This code was adapted by Vicente from Howard Hinnant's experimental work
// on chrono i/o to Boost

#ifndef BOOST_CHRONO_IO_IOS_BASE_STATE_HPP
#define BOOST_CHRONO_IO_IOS_BASE_STATE_HPP

#include <boost/chrono/config.hpp>
#include <locale>
#include <boost/chrono/io/duration_style.hpp>
#include <boost/chrono/io/timezone.hpp>
#include <boost/chrono/io/utility/ios_base_state_ptr.hpp>

namespace boost
{
  namespace chrono
  {

    class fmt_masks : public ios_flags<fmt_masks>
    {
      typedef ios_flags<fmt_masks> base_type;
      fmt_masks& operator=(fmt_masks const& rhs) ;

    public:
      fmt_masks(std::ios_base& ios): base_type(ios) {}
      enum type
      {
        uses_symbol = 1 << 0,
        uses_local  = 1 << 1
      };

      inline duration_style get_duration_style()
      {
        return (flags() & uses_symbol) ? duration_style::symbol : duration_style::prefix;
      }
      inline void set_duration_style(duration_style style)
      {
        if (style == duration_style::symbol)
          setf(uses_symbol);
        else
          unsetf(uses_symbol);
      }

      inline timezone get_timezone()
      {
        return (flags() & uses_local) ? timezone::local : timezone::utc;
      }
      inline void set_timezone(timezone tz)
      {
        if (tz == timezone::local)
          setf(uses_local);
        else
          unsetf(uses_local);
      }
    };
    namespace detail
    {
      namespace /**/ {
        xalloc_key_initializer<fmt_masks > fmt_masks_xalloc_key_initializer;
      } // namespace
    } // namespace detail

    inline duration_style get_duration_style(std::ios_base & ios)
    {
      return fmt_masks(ios).get_duration_style();
    }
    inline void set_duration_style(std::ios_base& ios, duration_style style)
    {
      fmt_masks(ios).set_duration_style(style);
    }
    inline std::ios_base&  symbol_format(std::ios_base& ios)
    {
      fmt_masks(ios).setf(fmt_masks::uses_symbol);
      return ios;
    }
    inline std::ios_base&  name_format(std::ios_base& ios)
    {
      fmt_masks(ios).unsetf(fmt_masks::uses_symbol);
      return ios;
    }

    inline timezone get_timezone(std::ios_base & ios)
    {
      return fmt_masks(ios).get_timezone();
    }
    inline void set_timezone(std::ios_base& ios, timezone tz)
    {
      fmt_masks(ios).set_timezone(tz);
    }
    inline std::ios_base& local_timezone(std::ios_base& ios)
    {
      fmt_masks(ios).setf(fmt_masks::uses_local);
      return ios;
    }

    inline std::ios_base& utc_timezone(std::ios_base& ios)
    {
      fmt_masks(ios).unsetf(fmt_masks::uses_local);
      return ios;
    }

    namespace detail
    {

      template<typename CharT>
      struct ios_base_data_aux
      {
        std::basic_string<CharT> time_fmt;
        std::basic_string<CharT> duration_fmt;
      public:

        ios_base_data_aux()
        //:
        //  time_fmt(""),
        //  duration_fmt("")
        {
        }
      };
      template<typename CharT>
      struct ios_base_data  {};
      namespace /**/ {
        xalloc_key_initializer<detail::ios_base_data<char>      > ios_base_data_aux_xalloc_key_initializer;
        xalloc_key_initializer<detail::ios_base_data<wchar_t>   > wios_base_data_aux_xalloc_key_initializer;
#if BOOST_CHRONO_HAS_UNICODE_SUPPORT
        xalloc_key_initializer<detail::ios_base_data<char16_t>  > u16ios_base_data_aux_xalloc_key_initializer;
        xalloc_key_initializer<detail::ios_base_data<char32_t>  > u32ios_base_data_aux_xalloc_key_initializer;
#endif
      } // namespace
    } // namespace detail

    template<typename CharT>
    inline std::basic_string<CharT> get_time_fmt(std::ios_base & ios)
    {
      ios_state_not_null_ptr<detail::ios_base_data<CharT>, detail::ios_base_data_aux<CharT> > ptr(ios);
      return ptr->time_fmt;
    }
    template<typename CharT>
    inline void set_time_fmt(std::ios_base& ios, std::basic_string<
        CharT> const& fmt)
    {
      ios_state_not_null_ptr<detail::ios_base_data<CharT>, detail::ios_base_data_aux<CharT> > ptr(ios);
      ptr->time_fmt = fmt;
    }

  } // chrono
} // boost

#endif  // header