#ifndef DATE_TIME_C_TIME_HPP___

#define DATE_TIME_C_TIME_HPP___

/* Copyright (c) 2002,2003,2005 CrystalClear Software, Inc.

 * Use, modification and distribution is subject to the 

 * Boost Software License, Version 1.0. (See accompanying

 * file LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt)

 * Author: Jeff Garland, Bart Garst 

 * $Date: 2008-11-12 14:37:53 -0500 (Wed, 12 Nov 2008) $

 */

/*! @file c_time.hpp

  Provide workarounds related to the ctime header

*/

#include <ctime>

#include <string> // to be able to convert from string literals to exceptions

#include <stdexcept>

#include <boost/throw_exception.hpp>

#include <boost/date_time/compiler_config.hpp>

//Work around libraries that don't put time_t and time in namespace std

#ifdef BOOST_NO_STDC_NAMESPACE

namespace std { using ::time_t; using ::time; using ::localtime;

                using ::tm;  using ::gmtime; }

#endif // BOOST_NO_STDC_NAMESPACE

//The following is used to support high precision time clocks

#ifdef BOOST_HAS_GETTIMEOFDAY

#include <sys/time.h>

#endif

#ifdef BOOST_HAS_FTIME

#include <time.h>

#endif

namespace boost {

namespace date_time {

  //! Provides a uniform interface to some 'ctime' functions

  /*! Provides a uniform interface to some ctime functions and 

   * their '_r' counterparts. The '_r' functions require a pointer to a 

   * user created std::tm struct whereas the regular functions use a 

   * staticly created struct and return a pointer to that. These wrapper 

   * functions require the user to create a std::tm struct and send in a 

   * pointer to it. A pointer to the user created struct will be returned.

   * All functions do proper checking of the C function results and throw

   * exceptions on error. Therefore the functions will never return NULL.

   */

  struct c_time {

    public:

#if defined(BOOST_DATE_TIME_HAS_REENTRANT_STD_FUNCTIONS)

      //! requires a pointer to a user created std::tm struct

      inline

      static std::tm* localtime(const std::time_t* t, std::tm* result)

      {

        // localtime_r() not in namespace std???

        result = localtime_r(t, result);

        if (!result)

          boost::throw_exception(std::runtime_error("could not convert calendar time to local time"));

        return result;

      }

      //! requires a pointer to a user created std::tm struct

      inline

      static std::tm* gmtime(const std::time_t* t, std::tm* result)

      {

        // gmtime_r() not in namespace std???

        result = gmtime_r(t, result);

        if (!result)

          boost::throw_exception(std::runtime_error("could not convert calendar time to UTC time"));

        return result;

      }

#else // BOOST_HAS_THREADS

#if (defined(_MSC_VER) && (_MSC_VER >= 1400))

#pragma warning(push) // preserve warning settings

#pragma warning(disable : 4996) // disable depricated localtime/gmtime warning on vc8

#endif // _MSC_VER >= 1400

      //! requires a pointer to a user created std::tm struct

      inline

      static std::tm* localtime(const std::time_t* t, std::tm* result)

      {

        result = std::localtime(t);

        if (!result)

          boost::throw_exception(std::runtime_error("could not convert calendar time to local time"));

        return result;

      }

      //! requires a pointer to a user created std::tm struct

      inline

      static std::tm* gmtime(const std::time_t* t, std::tm* result)

      {

        result = std::gmtime(t);

        if (!result)

          boost::throw_exception(std::runtime_error("could not convert calendar time to UTC time"));

        return result;

      }

#if (defined(_MSC_VER) && (_MSC_VER >= 1400))

#pragma warning(pop) // restore warnings to previous state

#endif // _MSC_VER >= 1400

#endif // BOOST_HAS_THREADS

  };

}} // namespaces

#endif // DATE_TIME_C_TIME_HPP___