Chris@16: //  (C) Copyright Howard Hinnant
Chris@16: //  (C) Copyright 2011 Vicente J. Botet Escriba
Chris@16: //  Use, modification and distribution are subject to the Boost Software License,
Chris@16: //  Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
Chris@16: //  http://www.boost.org/LICENSE_1_0.txt).
Chris@16: //
Chris@16: 
Chris@16: #ifndef BOOST_CHRONO_IO_TIME_POINT_GET_HPP
Chris@16: #define BOOST_CHRONO_IO_TIME_POINT_GET_HPP
Chris@16: 
Chris@16: #include <boost/chrono/config.hpp>
Chris@16: #include <boost/chrono/detail/scan_keyword.hpp>
Chris@16: #include <boost/chrono/io/time_point_units.hpp>
Chris@16: #include <boost/chrono/io/duration_get.hpp>
Chris@16: #include <boost/assert.hpp>
Chris@16: #include <locale>
Chris@16: #include <string>
Chris@16: 
Chris@16: /**
Chris@16:  * Duration formatting facet for input.
Chris@16:  */
Chris@16: namespace boost
Chris@16: {
Chris@16:   namespace chrono
Chris@16:   {
Chris@16: 
Chris@16:     template <class CharT, class InputIterator = std::istreambuf_iterator<CharT> >
Chris@16:     class time_point_get: public std::locale::facet
Chris@16:     {
Chris@16:     public:
Chris@16:       /**
Chris@16:        * Type of character the facet is instantiated on.
Chris@16:        */
Chris@16:       typedef CharT char_type;
Chris@16:       /**
Chris@16:        * Type of iterator used to scan the character buffer.
Chris@16:        */
Chris@16:       typedef InputIterator iter_type;
Chris@16: 
Chris@16:       /**
Chris@16:        * Construct a @c time_point_get facet.
Chris@16:        * @param refs
Chris@16:        * @Effects Construct a @c time_point_get facet.
Chris@16:        * If the @c refs argument is @c 0 then destruction of the object is
Chris@16:        * delegated to the @c locale, or locales, containing it. This allows
Chris@16:        * the user to ignore lifetime management issues. On the other had,
Chris@16:        * if @c refs is @c 1 then the object must be explicitly deleted;
Chris@16:        * the @c locale will not do so. In this case, the object can be
Chris@16:        * maintained across the lifetime of multiple locales.
Chris@16:        */
Chris@16: 
Chris@16:       explicit time_point_get(size_t refs = 0) :
Chris@16:         std::locale::facet(refs)
Chris@16:       {
Chris@16:       }
Chris@16: 
Chris@16:       /**
Chris@16:        * @param s start input stream iterator
Chris@16:        * @param end end input stream iterator
Chris@16:        * @param ios a reference to a ios_base
Chris@16:        * @param err the ios_base state
Chris@16:        * @param d the duration
Chris@16:        * @param pattern begin of the formatting pattern
Chris@16:        * @param pat_end end of the formatting pattern
Chris@16:        *
Chris@16:        * Requires: [pattern,pat_end) shall be a valid range.
Chris@16:        *
Chris@16:        * Effects: The function starts by evaluating err = std::ios_base::goodbit.
Chris@16:        * It then enters a loop, reading zero or more characters from s at
Chris@16:        * each iteration. Unless otherwise specified below, the loop
Chris@16:        * terminates when the first of the following conditions holds:
Chris@16:        * - The expression pattern == pat_end evaluates to true.
Chris@16:        * - The expression err == std::ios_base::goodbit evaluates to false.
Chris@16:        * - The expression s == end evaluates to true, in which case the
Chris@16:        * function evaluates err = std::ios_base::eofbit | std::ios_base::failbit.
Chris@16:        * - The next element of pattern is equal to '%', followed by a conversion
Chris@16:        * specifier character, the functions @c get_duration or @c get_epoch are called depending on
Chris@16:        * whether the format is @c 'd' or @c 'e'.
Chris@16:        * If the number of elements in the range [pattern,pat_end) is not
Chris@16:        * sufficient to unambiguously determine whether the conversion
Chris@16:        * specification is complete and valid, the function evaluates
Chris@16:        * err = std::ios_base::failbit. Otherwise, the function evaluates
Chris@16:        * s = do_get(s, end, ios, err, d). If err == std::ios_base::goodbit holds after
Chris@16:        * the evaluation of the expression, the function increments pattern to
Chris@16:        * point just past the end of the conversion specification and continues
Chris@16:        * looping.
Chris@16:        * - The expression isspace(*pattern, ios.getloc()) evaluates to true, in
Chris@16:        * which case the function first increments pattern until
Chris@16:        * pattern == pat_end || !isspace(*pattern, ios.getloc()) evaluates to true,
Chris@16:        * then advances s until s == end || !isspace(*s, ios.getloc()) is true,
Chris@16:        * and finally resumes looping.
Chris@16:        * - The next character read from s matches the element pointed to by
Chris@16:        * pattern in a case-insensitive comparison, in which case the function
Chris@16:        * evaluates ++pattern, ++s and continues looping. Otherwise, the function
Chris@16:        * evaluates err = std::ios_base::failbit.
Chris@16:        *
Chris@16:        * Returns: s
Chris@16:        */
Chris@16: 
Chris@16:       template <class Clock, class Duration>
Chris@16:       iter_type get(iter_type i, iter_type e, std::ios_base& is, std::ios_base::iostate& err,
Chris@16:           time_point<Clock, Duration> &tp, const char_type *pattern, const char_type *pat_end) const
Chris@16:       {
Chris@16:         if (std::has_facet<time_point_units<CharT> >(is.getloc()))
Chris@16:         {
Chris@16:           time_point_units<CharT> const &facet = std::use_facet<time_point_units<CharT> >(is.getloc());
Chris@16:           return get(facet, i, e, is, err, tp, pattern, pat_end);
Chris@16:         }
Chris@16:         else
Chris@16:         {
Chris@16:           time_point_units_default<CharT> facet;
Chris@16:           return get(facet, i, e, is, err, tp, pattern, pat_end);
Chris@16:         }
Chris@16:       }
Chris@16: 
Chris@16:       template <class Clock, class Duration>
Chris@16:       iter_type get(time_point_units<CharT> const &facet, iter_type s, iter_type end, std::ios_base& ios,
Chris@16:           std::ios_base::iostate& err, time_point<Clock, Duration> &tp, const char_type *pattern,
Chris@16:           const char_type *pat_end) const
Chris@16:       {
Chris@16: 
Chris@16:         Duration d;
Chris@16:         bool duration_found = false, epoch_found = false;
Chris@16: 
Chris@16:         const std::ctype<char_type>& ct = std::use_facet<std::ctype<char_type> >(ios.getloc());
Chris@16:         err = std::ios_base::goodbit;
Chris@16:         while (pattern != pat_end && err == std::ios_base::goodbit)
Chris@16:         {
Chris@16:           if (s == end)
Chris@16:           {
Chris@16:             err |= std::ios_base::eofbit;
Chris@16:             break;
Chris@16:           }
Chris@16:           if (ct.narrow(*pattern, 0) == '%')
Chris@16:           {
Chris@16:             if (++pattern == pat_end)
Chris@16:             {
Chris@16:               err |= std::ios_base::failbit;
Chris@16:               return s;
Chris@16:             }
Chris@16:             char cmd = ct.narrow(*pattern, 0);
Chris@16:             switch (cmd)
Chris@16:             {
Chris@16:             case 'd':
Chris@16:             {
Chris@16:               if (duration_found)
Chris@16:               {
Chris@16:                 err |= std::ios_base::failbit;
Chris@16:                 return s;
Chris@16:               }
Chris@16:               duration_found = true;
Chris@16:               s = get_duration(s, end, ios, err, d);
Chris@16:               if (err & (std::ios_base::badbit | std::ios_base::failbit))
Chris@16:               {
Chris@16:                 return s;
Chris@16:               }
Chris@16:               break;
Chris@16:             }
Chris@16:             case 'e':
Chris@16:             {
Chris@16:               if (epoch_found)
Chris@16:               {
Chris@16:                 err |= std::ios_base::failbit;
Chris@16:                 return s;
Chris@16:               }
Chris@16:               epoch_found = true;
Chris@16:               s = get_epoch<Clock> (facet, s, end, ios, err);
Chris@16:               if (err & (std::ios_base::badbit | std::ios_base::failbit))
Chris@16:               {
Chris@16:                 return s;
Chris@16:               }
Chris@16:               break;
Chris@16:             }
Chris@16:             default:
Chris@16:               BOOST_ASSERT(false && "Boost::Chrono internal error.");
Chris@16:               break;
Chris@16:             }
Chris@16: 
Chris@16:             ++pattern;
Chris@16:           }
Chris@16:           else if (ct.is(std::ctype_base::space, *pattern))
Chris@16:           {
Chris@16:             for (++pattern; pattern != pat_end && ct.is(std::ctype_base::space, *pattern); ++pattern)
Chris@16:               ;
Chris@16:             for (; s != end && ct.is(std::ctype_base::space, *s); ++s)
Chris@16:               ;
Chris@16:           }
Chris@16:           else if (ct.toupper(*s) == ct.toupper(*pattern))
Chris@16:           {
Chris@16:             ++s;
Chris@16:             ++pattern;
Chris@16:           }
Chris@16:           else
Chris@16:           {
Chris@16:             err |= std::ios_base::failbit;
Chris@16:           }
Chris@16:         }
Chris@16: 
Chris@16:         // Success!  Store it.
Chris@16:         tp = time_point<Clock, Duration> (d);
Chris@16:         return s;
Chris@16:       }
Chris@16: 
Chris@16:       /**
Chris@16:        *
Chris@16:        * @param s an input stream iterator
Chris@16:        * @param ios a reference to a ios_base
Chris@16:        * @param d the duration
Chris@16:        * Stores the duration pattern from the @c duration_unit facet in let say @c str. Last as if
Chris@16:        * @code
Chris@16:        *   return get(s, end, ios, err, ios, d, str.data(), str.data() + str.size());
Chris@16:        * @codeend
Chris@16:        * @Returns An iterator pointing just beyond the last character that can be determined to be part of a valid name
Chris@16:        */
Chris@16:       template <class Clock, class Duration>
Chris@16:       iter_type get(iter_type i, iter_type e, std::ios_base& is, std::ios_base::iostate& err,
Chris@16:           time_point<Clock, Duration> &tp) const
Chris@16:       {
Chris@16:         if (std::has_facet<time_point_units<CharT> >(is.getloc()))
Chris@16:         {
Chris@16:           time_point_units<CharT> const &facet = std::use_facet<time_point_units<CharT> >(is.getloc());
Chris@16:           std::basic_string<CharT> str = facet.get_pattern();
Chris@16:           return get(facet, i, e, is, err, tp, str.data(), str.data() + str.size());
Chris@16:         }
Chris@16:         else
Chris@16:         {
Chris@16:           time_point_units_default<CharT> facet;
Chris@16:           std::basic_string<CharT> str = facet.get_pattern();
Chris@16:           return get(facet, i, e, is, err, tp, str.data(), str.data() + str.size());
Chris@16:         }
Chris@16:       }
Chris@16: 
Chris@16:       /**
Chris@16:        * As if
Chris@16:        * @code
Chris@16:        * return facet.get(s, end, ios, err, d);
Chris@16:        * @endcode
Chris@16:        * where @c facet is either the @c duration_get facet associated to the @c ios or an instance of the default @c duration_get facet.
Chris@16:        *
Chris@16:        * @Returns An iterator pointing just beyond the last character that can be determined to be part of a valid duration.
Chris@16:        */
Chris@16:       template <typename Rep, typename Period>
Chris@16:       iter_type get_duration(iter_type i, iter_type e, std::ios_base& is, std::ios_base::iostate& err,
Chris@16:           duration<Rep, Period>& d) const
Chris@16:       {
Chris@16:         if (std::has_facet<duration_get<CharT> >(is.getloc()))
Chris@16:         {
Chris@16:           duration_get<CharT> const &facet = std::use_facet<duration_get<CharT> >(is.getloc());
Chris@16:           return get_duration(facet, i, e, is, err, d);
Chris@16:         }
Chris@16:         else
Chris@16:         {
Chris@16:           duration_get<CharT> facet;
Chris@16:           return get_duration(facet, i, e, is, err, d);
Chris@16:         }
Chris@16:       }
Chris@16: 
Chris@16:       template <typename Rep, typename Period>
Chris@16:       iter_type get_duration(duration_get<CharT> const& facet, iter_type s, iter_type end, std::ios_base& ios,
Chris@16:           std::ios_base::iostate& err, duration<Rep, Period>& d) const
Chris@16:       {
Chris@16:         return facet.get(s, end, ios, err, d);
Chris@16:       }
Chris@16: 
Chris@16:       /**
Chris@16:        *
Chris@16:        * @Effects Let @c facet be the @c time_point_units facet associated to @c is or a new instance of the default @c time_point_units_default facet.
Chris@16:        * Let @c epoch be the epoch string associated to the Clock using this facet.
Chris@16:        * Scans @c i to match @c epoch or @c e is reached.
Chris@16:        *
Chris@16:        * If not match before the @c e is reached @c std::ios_base::failbit is set in @c err.
Chris@16:        * If @c e is reached @c std::ios_base::failbit is set in @c err.
Chris@16:        *
Chris@16:        * @Returns An iterator pointing just beyond the last character that can be determined to be part of a valid epoch.
Chris@16:        */
Chris@16:       template <class Clock>
Chris@16:       iter_type get_epoch(iter_type i, iter_type e, std::ios_base& is, std::ios_base::iostate& err) const
Chris@16:       {
Chris@16:         if (std::has_facet<time_point_units<CharT> >(is.getloc()))
Chris@16:         {
Chris@16:           time_point_units<CharT> const &facet = std::use_facet<time_point_units<CharT> >(is.getloc());
Chris@16:           return get_epoch(facet, i, e, is, err);
Chris@16:         }
Chris@16:         else
Chris@16:         {
Chris@16:           time_point_units_default<CharT> facet;
Chris@16:           return get_epoch(facet, i, e, is, err);
Chris@16:         }
Chris@16:       }
Chris@16: 
Chris@16:       template <class Clock>
Chris@16:       iter_type get_epoch(time_point_units<CharT> const &facet, iter_type i, iter_type e, std::ios_base&,
Chris@16:           std::ios_base::iostate& err) const
Chris@16:       {
Chris@16:         const std::basic_string<CharT> epoch = facet.template get_epoch<Clock> ();
Chris@16:         std::ptrdiff_t k = chrono_detail::scan_keyword(i, e, &epoch, &epoch + 1,
Chris@16:         //~ std::use_facet<std::ctype<CharT> >(ios.getloc()),
Chris@16:             err) - &epoch;
Chris@16:         if (k == 1)
Chris@16:         {
Chris@16:           err |= std::ios_base::failbit;
Chris@16:           return i;
Chris@16:         }
Chris@16:         return i;
Chris@16:       }
Chris@16: 
Chris@16:       /**
Chris@16:        * Unique identifier for this type of facet.
Chris@16:        */
Chris@16:       static std::locale::id id;
Chris@16: 
Chris@16:       /**
Chris@16:        * @Effects Destroy the facet
Chris@16:        */
Chris@16:       ~time_point_get()
Chris@16:       {
Chris@16:       }
Chris@16:     };
Chris@16: 
Chris@16:     /**
Chris@16:      * Unique identifier for this type of facet.
Chris@16:      */
Chris@16:     template <class CharT, class InputIterator>
Chris@16:     std::locale::id time_point_get<CharT, InputIterator>::id;
Chris@16: 
Chris@16:   } // chrono
Chris@16: }
Chris@16: // boost
Chris@16: 
Chris@16: #endif  // header