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_DURATION_GET_HPP
Chris@16: #define BOOST_CHRONO_IO_DURATION_GET_HPP
Chris@16: 
Chris@16: #include <boost/chrono/config.hpp>
Chris@16: #include <string>
Chris@16: #include <boost/type_traits/is_scalar.hpp>
Chris@16: #include <boost/utility/enable_if.hpp>
Chris@16: #include <boost/type_traits/is_signed.hpp>
Chris@16: #include <boost/mpl/if.hpp>
Chris@101: #include <boost/integer/common_factor_rt.hpp>
Chris@16: #include <boost/chrono/detail/scan_keyword.hpp>
Chris@16: #include <boost/chrono/detail/no_warning/signed_unsigned_cmp.hpp>
Chris@101: #include <boost/chrono/process_cpu_clocks.hpp>
Chris@16: 
Chris@16: #include <boost/assert.hpp>
Chris@16: #include <locale>
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:     namespace detail
Chris@16:     {
Chris@16:       template <class Rep, bool = is_scalar<Rep>::value>
Chris@16:       struct duration_io_intermediate
Chris@16:       {
Chris@16:         typedef Rep type;
Chris@16:       };
Chris@16: 
Chris@16:       template <class Rep>
Chris@16:       struct duration_io_intermediate<Rep, true>
Chris@16:       {
Chris@16:         typedef typename mpl::if_c<is_floating_point<Rep>::value, long double, typename mpl::if_c<
Chris@16:             is_signed<Rep>::value, long long, unsigned long long>::type>::type type;
Chris@16:       };
Chris@16: 
Chris@101:       template <class Rep>
Chris@101:       struct duration_io_intermediate<process_times<Rep>, false>
Chris@101:       {
Chris@101:         typedef process_times<typename duration_io_intermediate<Rep>::type> type;
Chris@101:       };
Chris@101: 
Chris@16:       template <typename intermediate_type>
Chris@16:       typename enable_if<is_integral<intermediate_type> , bool>::type reduce(intermediate_type& r,
Chris@16:           unsigned long long& den, std::ios_base::iostate& err)
Chris@16:       {
Chris@16:         typedef typename common_type<intermediate_type, unsigned long long>::type common_type_t;
Chris@16: 
Chris@16:         // Reduce r * num / den
Chris@101:         common_type_t t = integer::gcd<common_type_t>(common_type_t(r), common_type_t(den));
Chris@16:         r /= t;
Chris@16:         den /= t;
Chris@16:         if (den != 1)
Chris@16:         {
Chris@16:           // Conversion to Period is integral and not exact
Chris@16:           err |= std::ios_base::failbit;
Chris@16:           return false;
Chris@16:         }
Chris@16:         return true;
Chris@16:       }
Chris@16:       template <typename intermediate_type>
Chris@16:       typename disable_if<is_integral<intermediate_type> , bool>::type reduce(intermediate_type&, unsigned long long&,
Chris@16:           std::ios_base::iostate&)
Chris@16:       {
Chris@16:         return true;
Chris@16:       }
Chris@16: 
Chris@16:     }
Chris@16: 
Chris@16:     /**
Chris@16:      * @c duration_get is used to parse a character sequence, extracting
Chris@16:      * components of a duration into a class duration.
Chris@16:      * Each get member parses a format as produced by a corresponding format specifier to time_put<>::put.
Chris@16:      * If the sequence being parsed matches the correct format, the
Chris@16:      * corresponding member of the class duration argument are set to the
Chris@16:      * value used to produce the sequence;
Chris@16:      * otherwise either an error is reported or unspecified values are assigned.
Chris@16:      * In other words, user confirmation is required for reliable parsing of
Chris@16:      * user-entered durations, but machine-generated formats can be parsed
Chris@16:      * reliably. This allows parsers to be aggressive about interpreting user
Chris@16:      * variations on standard formats.
Chris@16:      *
Chris@16:      * If the end iterator is reached during parsing of the get() member
Chris@16:      * function, the member sets std::ios_base::eofbit in err.
Chris@16:      */
Chris@16:     template <class CharT, class InputIterator = std::istreambuf_iterator<CharT> >
Chris@16:     class duration_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 character string passed to member functions.
Chris@16:        */
Chris@16:       typedef std::basic_string<CharT> string_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 duration_get facet.
Chris@16:        * @param refs
Chris@16:        * @Effects Construct a @c duration_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 duration_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, format.
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 = get_value(s, end, ios, err, r) when the conversion specification is 'v' and
Chris@16:        * s = get_value(s, end, ios, err, rt) when the conversion specification is 'u'.
Chris@16:        * 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:        * Once r and rt are retrieved,
Chris@16:        * Returns: s
Chris@16:        */
Chris@16:       template <typename Rep, typename Period>
Chris@16:       iter_type get(iter_type s, iter_type end, std::ios_base& ios, std::ios_base::iostate& err,
Chris@16:           duration<Rep, Period> &d, const char_type *pattern, const char_type *pat_end) const
Chris@16:       {
Chris@16:         if (std::has_facet<duration_units<CharT> >(ios.getloc()))
Chris@16:         {
Chris@16:           duration_units<CharT> const&facet = std::use_facet<duration_units<CharT> >(ios.getloc());
Chris@16:           return get(facet, s, end, ios, err, d, pattern, pat_end);
Chris@16:         }
Chris@16:         else
Chris@16:         {
Chris@16:           duration_units_default<CharT> facet;
Chris@16:           return get(facet, s, end, ios, err, d, pattern, pat_end);
Chris@16:         }
Chris@16:       }
Chris@16: 
Chris@16:       template <typename Rep, typename Period>
Chris@16:       iter_type get(duration_units<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 char_type *pattern, const char_type *pat_end) const
Chris@16:       {
Chris@16: 
Chris@16:         typedef typename detail::duration_io_intermediate<Rep>::type intermediate_type;
Chris@16:         intermediate_type r;
Chris@16:         rt_ratio rt;
Chris@16:         bool value_found = false, unit_found = false;
Chris@16: 
Chris@16:         const std::ctype<char_type>& ct = std::use_facet<std::ctype<char_type> >(ios.getloc());
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 'v':
Chris@16:             {
Chris@16:               if (value_found)
Chris@16:               {
Chris@16:                 err |= std::ios_base::failbit;
Chris@16:                 return s;
Chris@16:               }
Chris@16:               value_found = true;
Chris@16:               s = get_value(s, end, ios, err, r);
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 'u':
Chris@16:             {
Chris@16:               if (unit_found)
Chris@16:               {
Chris@16:                 err |= std::ios_base::failbit;
Chris@16:                 return s;
Chris@16:               }
Chris@16:               unit_found = true;
Chris@16:               s = get_unit(facet, s, end, ios, err, rt);
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:             return s;
Chris@16:           }
Chris@16: 
Chris@16:         }
Chris@16: 
Chris@16:         unsigned long long num = rt.num;
Chris@16:         unsigned long long den = rt.den;
Chris@16: 
Chris@16:         // r should be multiplied by (num/den) / Period
Chris@16:         // Reduce (num/den) / Period to lowest terms
Chris@101:         unsigned long long gcd_n1_n2 = integer::gcd<unsigned long long>(num, Period::num);
Chris@101:         unsigned long long gcd_d1_d2 = integer::gcd<unsigned long long>(den, Period::den);
Chris@16:         num /= gcd_n1_n2;
Chris@16:         den /= gcd_d1_d2;
Chris@16:         unsigned long long n2 = Period::num / gcd_n1_n2;
Chris@16:         unsigned long long d2 = Period::den / gcd_d1_d2;
Chris@16:         if (num > (std::numeric_limits<unsigned long long>::max)() / d2 || den
Chris@16:             > (std::numeric_limits<unsigned long long>::max)() / n2)
Chris@16:         {
Chris@16:           // (num/den) / Period overflows
Chris@16:           err |= std::ios_base::failbit;
Chris@16:           return s;
Chris@16:         }
Chris@16:         num *= d2;
Chris@16:         den *= n2;
Chris@16: 
Chris@16:         typedef typename common_type<intermediate_type, unsigned long long>::type common_type_t;
Chris@16: 
Chris@16:         // num / den is now factor to multiply by r
Chris@16:         if (!detail::reduce(r, den, err)) return s;
Chris@16: 
Chris@16:         if (chrono::detail::gt(r, ( (duration_values<common_type_t>::max)() / num)))
Chris@16:         {
Chris@16:           // Conversion to Period overflowed
Chris@16:           err |= std::ios_base::failbit;
Chris@16:           return s;
Chris@16:         }
Chris@16:         common_type_t t = r * num;
Chris@16:         t /= den;
Chris@101:         if (t > duration_values<common_type_t>::zero())
Chris@16:         {
Chris@16:           Rep pt = t;
Chris@16:           if ( (duration_values<Rep>::max)() < pt)
Chris@16:           {
Chris@16:             // Conversion to Period overflowed
Chris@16:             err |= std::ios_base::failbit;
Chris@16:             return s;
Chris@16:           }
Chris@16:         }
Chris@16:         // Success!  Store it.
Chris@16:         r = Rep(t);
Chris@16:         d = duration<Rep, Period> (r);
Chris@16: 
Chris@16:         return s;
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:        * 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 <typename Rep, typename Period>
Chris@16:       iter_type get(iter_type s, iter_type end, std::ios_base& ios, std::ios_base::iostate& err,
Chris@16:           duration<Rep, Period> & d) const
Chris@16:       {
Chris@16:         if (std::has_facet<duration_units<CharT> >(ios.getloc()))
Chris@16:         {
Chris@16:           duration_units<CharT> const&facet = std::use_facet<duration_units<CharT> >(ios.getloc());
Chris@16:           std::basic_string<CharT> str = facet.get_pattern();
Chris@16:           return get(facet, s, end, ios, err, d, str.data(), str.data() + str.size());
Chris@16:         }
Chris@16:         else
Chris@16:         {
Chris@16:           duration_units_default<CharT> facet;
Chris@16:           std::basic_string<CharT> str = facet.get_pattern();
Chris@16:           return get(facet, s, end, ios, err, d, str.data(), str.data() + str.size());
Chris@16:         }
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 r a reference to the duration representation.
Chris@16:        * @Effects As if
Chris@16:        * @code
Chris@16:        * return std::use_facet<std::num_get<cahr_type, iter_type> >(ios.getloc()).get(s, end, ios, err, r);
Chris@16:        * @endcode
Chris@16:        *
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 <typename Rep>
Chris@16:       iter_type get_value(iter_type s, iter_type end, std::ios_base& ios, std::ios_base::iostate& err, Rep& r) const
Chris@16:       {
Chris@16:         return std::use_facet<std::num_get<CharT, iter_type> >(ios.getloc()).get(s, end, ios, err, r);
Chris@16:       }
Chris@101:       template <typename Rep>
Chris@101:       iter_type get_value(iter_type s, iter_type end, std::ios_base& ios, std::ios_base::iostate& err, process_times<Rep>& r) const
Chris@101:       {
Chris@101:         if (s == end) {
Chris@101:             err |= std::ios_base::eofbit;
Chris@101:             return s;
Chris@101:         } else if (*s != '{') { // mandatory '{'
Chris@101:             err |= std::ios_base::failbit;
Chris@101:             return s;
Chris@101:         }
Chris@101:         ++s;
Chris@101:         s = std::use_facet<std::num_get<CharT, iter_type> >(ios.getloc()).get(s, end, ios, err, r.real);
Chris@101:         if (s == end) {
Chris@101:             err |= std::ios_base::eofbit;
Chris@101:             return s;
Chris@101:         } else if (*s != ';') { // mandatory ';'
Chris@101:             err |= std::ios_base::failbit;
Chris@101:             return s;
Chris@101:         }
Chris@101:         ++s;
Chris@101:         s = std::use_facet<std::num_get<CharT, iter_type> >(ios.getloc()).get(s, end, ios, err, r.user);
Chris@101:         if (s == end) {
Chris@101:             err |= std::ios_base::eofbit;
Chris@101:             return s;
Chris@101:         } else if (*s != ';') { // mandatory ';'
Chris@101:             err |= std::ios_base::failbit;
Chris@101:             return s;
Chris@101:         }
Chris@101:         ++s;
Chris@101:         s = std::use_facet<std::num_get<CharT, iter_type> >(ios.getloc()).get(s, end, ios, err, r.system);
Chris@101:         if (s == end) {
Chris@101:             err |= std::ios_base::eofbit;
Chris@101:             return s;
Chris@101:         } else if (*s != '}') { // mandatory '}'
Chris@101:             err |= std::ios_base::failbit;
Chris@101:             return s;
Chris@101:         }
Chris@101:         return s;
Chris@101:       }
Chris@16: 
Chris@16:       /**
Chris@16:        *
Chris@16:        * @param s start input stream iterator
Chris@16:        * @param e 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 rt a reference to the duration run-time ratio.
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:       iter_type get_unit(iter_type i, iter_type e, std::ios_base& is, std::ios_base::iostate& err, rt_ratio &rt) const
Chris@16:       {
Chris@16:         if (std::has_facet<duration_units<CharT> >(is.getloc()))
Chris@16:         {
Chris@16:           return get_unit(std::use_facet<duration_units<CharT> >(is.getloc()), i, e, is, err, rt);
Chris@16:         }
Chris@16:         else
Chris@16:         {
Chris@16:           duration_units_default<CharT> facet;
Chris@16:           return get_unit(facet, i, e, is, err, rt);
Chris@16:         }
Chris@16:       }
Chris@16: 
Chris@16: 
Chris@16:       iter_type get_unit(duration_units<CharT> const &facet, iter_type i, iter_type e, std::ios_base& is,
Chris@16:           std::ios_base::iostate& err, rt_ratio &rt) const
Chris@16:       {
Chris@16: 
Chris@16:         if (*i == '[')
Chris@16:         {
Chris@16:           // parse [N/D]s or [N/D]second or [N/D]seconds format
Chris@16:           ++i;
Chris@16:           i = std::use_facet<std::num_get<CharT, iter_type> >(is.getloc()).get(i, e, is, err, rt.num);
Chris@16:           if ( (err & std::ios_base::failbit) != 0)
Chris@16:           {
Chris@16:             return i;
Chris@16:           }
Chris@16: 
Chris@16:           if (i == e)
Chris@16:           {
Chris@16:             err |= std::ios_base::failbit;
Chris@16:             return i;
Chris@16:           }
Chris@16:           CharT x = *i++;
Chris@16:           if (x != '/')
Chris@16:           {
Chris@16:             err |= std::ios_base::failbit;
Chris@16:             return i;
Chris@16:           }
Chris@16:           i = std::use_facet<std::num_get<CharT, iter_type> >(is.getloc()).get(i, e, is, err, rt.den);
Chris@16:           if ( (err & std::ios_base::failbit) != 0)
Chris@16:           {
Chris@16:             return i;
Chris@16:           }
Chris@16:           if (i == e)
Chris@16:           {
Chris@16:             err |= std::ios_base::failbit;
Chris@16:             return i;
Chris@16:           }
Chris@16:           if (*i != ']')
Chris@16:           {
Chris@16:             err |= std::ios_base::failbit;
Chris@16:             return i;
Chris@16:           }
Chris@16:           ++i;
Chris@16:           if (i == e)
Chris@16:           {
Chris@16:             err |= std::ios_base::failbit;
Chris@16:             return i;
Chris@16:           }
Chris@16:           // parse s or second or seconds
Chris@16:           return do_get_n_d_valid_unit(facet, i, e, is, err);
Chris@16:         }
Chris@16:         else
Chris@16:         {
Chris@16:           return do_get_valid_unit(facet, i, e, is, err, rt);
Chris@16:         }
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:       ~duration_get()
Chris@16:       {
Chris@16:       }
Chris@16: 
Chris@16:     protected:
Chris@16: 
Chris@16:       /**
Chris@16:        * Extracts the run-time ratio associated to the duration when it is given in prefix form.
Chris@16:        *
Chris@16:        * This is an extension point of this facet so that we can take in account other periods that can have a useful
Chris@16:        * translation in other contexts, as e.g. days and weeks.
Chris@16:        *
Chris@16:        * @param facet the duration_units facet
Chris@16:        * @param i start input stream iterator.
Chris@16:        * @param e end input stream iterator.
Chris@16:        * @param ios a reference to a ios_base.
Chris@16:        * @param err the ios_base state.
Chris@16:        * @return @c s
Chris@16:        */
Chris@16:       iter_type do_get_n_d_valid_unit(duration_units<CharT> const &facet, iter_type i, iter_type e,
Chris@16:           std::ios_base&, std::ios_base::iostate& err) const
Chris@16:       {
Chris@16:         // parse SI name, short or long
Chris@16: 
Chris@16:         const string_type* units = facet.get_n_d_valid_units_start();
Chris@16:         const string_type* units_end = facet.get_n_d_valid_units_end();
Chris@16: 
Chris@16:         const string_type* k = chrono_detail::scan_keyword(i, e, units, units_end,
Chris@16:         //~ std::use_facet<std::ctype<CharT> >(loc),
Chris@16:             err);
Chris@16:         if (err & (std::ios_base::badbit | std::ios_base::failbit))
Chris@16:         {
Chris@16:           return i;
Chris@16:         }
Chris@16:         if (!facet.match_n_d_valid_unit(k))
Chris@16:         {
Chris@16:           err |= std::ios_base::failbit;
Chris@16:         }
Chris@16:         return i;
Chris@16:       }
Chris@16: 
Chris@16:       /**
Chris@16:        * Extracts the run-time ratio associated to the duration when it is given in prefix form.
Chris@16:        *
Chris@16:        * This is an extension point of this facet so that we can take in account other periods that can have a useful
Chris@16:        * translation in other contexts, as e.g. days and weeks.
Chris@16:        *
Chris@16:        * @param facet the duration_units facet
Chris@16:        * @param i start input stream iterator.
Chris@16:        * @param e 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 rt a reference to the duration run-time ratio.
Chris@16:        * @Effects
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:       iter_type do_get_valid_unit(duration_units<CharT> const &facet, iter_type i, iter_type e,
Chris@16:           std::ios_base&, std::ios_base::iostate& err, rt_ratio &rt) const
Chris@16:       {
Chris@16:         // parse SI name, short or long
Chris@16: 
Chris@16:         const string_type* units = facet.get_valid_units_start();
Chris@16:         const string_type* units_end = facet.get_valid_units_end();
Chris@16: 
Chris@16:         err = std::ios_base::goodbit;
Chris@16:         const string_type* k = chrono_detail::scan_keyword(i, e, units, units_end,
Chris@16:         //~ std::use_facet<std::ctype<CharT> >(loc),
Chris@16:             err);
Chris@16:         if (err & (std::ios_base::badbit | std::ios_base::failbit))
Chris@16:         {
Chris@16:           return i;
Chris@16:         }
Chris@16:         if (!facet.match_valid_unit(k, rt))
Chris@16:         {
Chris@16:           err |= std::ios_base::failbit;
Chris@16:         }
Chris@16:         return i;
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 duration_get<CharT, InputIterator>::id;
Chris@16: 
Chris@16:   } // chrono
Chris@16: }
Chris@16: // boost
Chris@16: 
Chris@16: #endif  // header