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Merge from trunk: r72184 (a lot of optimizations, new tests, fix inspection warnings).

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[SVN r72185]
This commit is contained in:
Antony Polukhin
2011-05-26 16:27:53 +00:00
parent 701d5f0bf0
commit a385c3ec99
4 changed files with 702 additions and 44 deletions
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include/boost/lexical_cast.hpp
+532 -29
View File
@@ -11,8 +11,8 @@
// enhanced with contributions from Terje Slettebo,
// with additional fixes and suggestions from Gennaro Prota,
// Beman Dawes, Dave Abrahams, Daryle Walker, Peter Dimov,
// Alexander Nasonov and other Boosters
// when: November 2000, March 2003, June 2005, June 2006
// Alexander Nasonov, Antony Polukhin and other Boosters
// when: November 2000, March 2003, June 2005, June 2006, March 2011
#include <climits>
#include <cstddef>
@@ -20,12 +20,18 @@
#include <string>
#include <typeinfo>
#include <exception>
#include <cmath>
#include <boost/config.hpp>
#include <boost/limits.hpp>
#include <boost/mpl/if.hpp>
#include <boost/throw_exception.hpp>
#include <boost/type_traits/is_pointer.hpp>
#include <boost/type_traits/is_integral.hpp>
#include <boost/type_traits/is_arithmetic.hpp>
#include <boost/numeric/conversion/cast.hpp>
#include <boost/type_traits/ice.hpp>
#include <boost/type_traits/make_unsigned.hpp>
#include <boost/type_traits/is_signed.hpp>
#include <boost/call_traits.hpp>
#include <boost/static_assert.hpp>
#include <boost/detail/lcast_precision.hpp>
@@ -457,7 +463,7 @@ namespace boost
#endif // #ifndef BOOST_LCAST_NO_COMPILE_TIME_PRECISION
}
namespace detail // '0' and '-' constants
namespace detail // '0', '+' and '-' constants
{
template<typename CharT> struct lcast_char_constants;
@@ -466,6 +472,7 @@ namespace boost
{
BOOST_STATIC_CONSTANT(char, zero = '0');
BOOST_STATIC_CONSTANT(char, minus = '-');
BOOST_STATIC_CONSTANT(char, plus = '+');
};
#ifndef BOOST_LCAST_NO_WCHAR_T
@@ -474,6 +481,7 @@ namespace boost
{
BOOST_STATIC_CONSTANT(wchar_t, zero = L'0');
BOOST_STATIC_CONSTANT(wchar_t, minus = L'-');
BOOST_STATIC_CONSTANT(wchar_t, plus = L'+');
};
#endif
}
@@ -571,6 +579,86 @@ namespace boost
}
}
namespace detail // lcast_ret_unsigned
{
template<class Traits, class T, class CharT>
inline bool lcast_ret_unsigned(T& value, const CharT* const begin, const CharT* end)
{
#ifndef BOOST_NO_LIMITS_COMPILE_TIME_CONSTANTS
BOOST_STATIC_ASSERT(!std::numeric_limits<T>::is_signed);
#endif
typedef typename Traits::int_type int_type;
CharT const czero = lcast_char_constants<CharT>::zero;
--end;
value = 0;
if ( *end < czero || *end >= czero + 10 || begin > end)
return false;
value = *end - czero;
--end;
T multiplier = 1;
#ifndef BOOST_LEXICAL_CAST_ASSUME_C_LOCALE
// TODO: use BOOST_NO_STD_LOCALE
std::locale loc;
typedef std::numpunct<CharT> numpunct;
numpunct const& np = BOOST_USE_FACET(numpunct, loc);
std::string const& grouping = np.grouping();
std::string::size_type const grouping_size = grouping.size();
/* According to [22.2.2.1.2] of Programming languages - C++
* we MUST check for correct grouping
*/
if (grouping_size)
{
unsigned char current_grouping = 0;
CharT const thousands_sep = grouping_size ? np.thousands_sep() : 0;
char remained = grouping[current_grouping] - 1;
for(;end>=begin; --end)
{
if (remained) {
T const new_sub_value = multiplier * 10 * (*end - czero);
if (*end < czero || *end >= czero + 10
/* detecting overflow */
|| new_sub_value/10 != multiplier * (*end - czero)
|| static_cast<T>((std::numeric_limits<T>::max)()-new_sub_value) < value
)
return false;
value += new_sub_value;
multiplier *= 10;
--remained;
} else {
if ( !Traits::eq(*end, thousands_sep) || begin == end ) return false;
if (current_grouping < grouping_size-1 ) ++current_grouping;
remained = grouping[current_grouping];
}
}
} else
#endif
{
while ( begin <= end )
{
T const new_sub_value = multiplier * 10 * (*end - czero);
if (*end < czero || *end >= czero + 10
/* detecting overflow */
|| new_sub_value/10 != multiplier * (*end - czero)
|| static_cast<T>((std::numeric_limits<T>::max)()-new_sub_value) < value
)
return false;
value += new_sub_value;
multiplier *= 10;
--end;
}
}
return true;
}
}
namespace detail // stream wrapper for handling lexical conversions
{
template<typename Target, typename Source, typename Traits>
@@ -756,8 +844,178 @@ namespace boost
bool operator<<(double);
bool operator<<(long double);
private:
template <typename Type>
bool input_operator_helper_unsigned(Type& output)
{
CharT const minus = lcast_char_constants<CharT>::minus;
CharT const plus = lcast_char_constants<CharT>::plus;
bool has_minus = false;
/* We won`t use `start' any more, so no need in decrementing it after */
if ( Traits::eq(minus,*start) )
{
++start;
has_minus = true;
} else if ( Traits::eq( plus, *start ) )
{
++start;
}
bool const succeed = lcast_ret_unsigned<Traits>(output, start, finish);
#if (defined _MSC_VER)
# pragma warning( push )
// C4146: unary minus operator applied to unsigned type, result still unsigned
# pragma warning( disable : 4146 )
#elif defined( __BORLANDC__ )
# pragma option push -w-8041
#endif
if (has_minus) output = static_cast<Type>(-output);
#if (defined _MSC_VER)
# pragma warning( pop )
#elif defined( __BORLANDC__ )
# pragma option pop
#endif
return succeed;
}
template <typename Type>
bool input_operator_helper_signed(Type& output)
{
CharT const minus = lcast_char_constants<CharT>::minus;
CharT const plus = lcast_char_constants<CharT>::plus;
typedef BOOST_DEDUCED_TYPENAME make_unsigned<Type>::type utype;
utype out_tmp =0;
bool has_minus = false;
/* We won`t use `start' any more, so no need in decrementing it after */
if ( Traits::eq(minus,*start) )
{
++start;
has_minus = true;
} else if ( Traits::eq(plus, *start) )
{
++start;
}
bool succeed = lcast_ret_unsigned<Traits>(out_tmp, start, finish);
if (has_minus) {
#if (defined _MSC_VER)
# pragma warning( push )
// C4146: unary minus operator applied to unsigned type, result still unsigned
# pragma warning( disable : 4146 )
#elif defined( __BORLANDC__ )
# pragma option push -w-8041
#endif
utype const comp_val = static_cast<utype>(-(std::numeric_limits<Type>::min)());
succeed = succeed && out_tmp<=comp_val;
output = -out_tmp;
#if (defined _MSC_VER)
# pragma warning( pop )
#elif defined( __BORLANDC__ )
# pragma option pop
#endif
} else {
utype const comp_val = static_cast<utype>((std::numeric_limits<Type>::max)());
succeed = succeed && out_tmp<=comp_val;
output = out_tmp;
}
return succeed;
}
public: // input
bool operator>>(unsigned short& output)
{
return input_operator_helper_unsigned(output);
}
bool operator>>(unsigned int& output)
{
return input_operator_helper_unsigned(output);
}
bool operator>>(unsigned long int& output)
{
return input_operator_helper_unsigned(output);
}
bool operator>>(short& output)
{
return input_operator_helper_signed(output);
}
bool operator>>(int& output)
{
return input_operator_helper_signed(output);
}
bool operator>>(long int& output)
{
return input_operator_helper_signed(output);
}
#if defined(BOOST_HAS_LONG_LONG)
bool operator>>( boost::ulong_long_type& output)
{
return input_operator_helper_unsigned(output);
}
bool operator>>(boost::long_long_type& output)
{
return input_operator_helper_signed(output);
}
#elif defined(BOOST_HAS_MS_INT64)
bool operator>>(unsigned __int64& output)
{
return input_operator_helper_unsigned(output);
}
bool operator>>(__int64& output)
{
return input_operator_helper_signed(output);
}
#endif
/*
* case "-0" || "0" || "+0" : output = false; return true;
* case "1" || "+1": output = true; return true;
* default: return false;
*/
bool operator>>(bool& output)
{
CharT const zero = lcast_char_constants<CharT>::zero;
CharT const plus = lcast_char_constants<CharT>::plus;
CharT const minus = lcast_char_constants<CharT>::minus;
switch(finish-start)
{
case 1:
output = Traits::eq(start[0], zero+1);
return output || Traits::eq(start[0], zero );
case 2:
if ( Traits::eq( plus, *start) )
{
++start;
output = Traits::eq(start[0], zero +1);
return output || Traits::eq(start[0], zero );
} else
{
output = false;
return Traits::eq( minus, *start)
&& Traits::eq( zero, start[1]);
}
default:
output = false; // Suppress warning about uninitalized variable
return false;
}
}
// Generic istream-based algorithm.
// lcast_streambuf_for_target<InputStreamable>::value is true.
template<typename InputStreamable>
@@ -1053,23 +1311,17 @@ namespace boost
template<class Target>
struct lcast_streambuf_for_target
{
BOOST_STATIC_CONSTANT(bool, value = true);
BOOST_STATIC_CONSTANT(bool, value =
(
::boost::type_traits::ice_or<
::boost::type_traits::ice_not< is_integral<Target>::value >::value,
is_same<Target, signed char>::value,
is_same<Target, unsigned char>::value
>::value
)
);
};
template<>
struct lcast_streambuf_for_target<char>
{
BOOST_STATIC_CONSTANT(bool, value = false);
};
#if !defined(BOOST_LCAST_NO_WCHAR_T) && !defined(BOOST_NO_INTRINSIC_WCHAR_T)
template<>
struct lcast_streambuf_for_target<wchar_t>
{
BOOST_STATIC_CONSTANT(bool, value = false);
};
#endif
#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
template<class Traits, class Alloc>
struct lcast_streambuf_for_target<
@@ -1161,23 +1413,273 @@ namespace boost
#if (defined _MSC_VER)
# pragma warning( pop )
#endif
template<typename T>
struct is_stdstring
{
BOOST_STATIC_CONSTANT(bool, value = false );
};
template<typename CharT, typename Traits, typename Alloc>
struct is_stdstring< std::basic_string<CharT, Traits, Alloc> >
{
BOOST_STATIC_CONSTANT(bool, value = true );
};
template<typename T>
struct is_char_or_wchar
{
#ifndef BOOST_LCAST_NO_WCHAR_T
BOOST_STATIC_CONSTANT(bool, value =
(
::boost::type_traits::ice_or<
is_same< T, char >::value,
is_same< T, wchar_t >::value,
is_same< T, unsigned char >::value,
is_same< T, signed char >::value
>::value
)
);
#else
BOOST_STATIC_CONSTANT(bool, value =
(
::boost::type_traits::ice_or<
is_same< T, char >::value,
is_same< T, unsigned char >::value,
is_same< T, signed char >::value
>::value
)
);
#endif
};
template<typename Target, typename Source>
struct is_arithmetic_and_not_xchars
{
BOOST_STATIC_CONSTANT(bool, value =
(
::boost::type_traits::ice_and<
is_arithmetic<Source>::value,
is_arithmetic<Target>::value,
::boost::type_traits::ice_not<
detail::is_char_or_wchar<Target>::value
>::value,
::boost::type_traits::ice_not<
detail::is_char_or_wchar<Source>::value
>::value
>::value
)
);
};
template<typename Target, typename Source>
struct is_xchar_to_xchar
{
BOOST_STATIC_CONSTANT(bool, value =
(
::boost::type_traits::ice_and<
is_same<Source,Target>::value,
is_char_or_wchar<Target>::value
>::value
)
);
};
template<typename Target, typename Source>
struct is_char_array_to_stdstring
{
BOOST_STATIC_CONSTANT(bool, value = false );
};
template<typename CharT, typename Traits, typename Alloc>
struct is_char_array_to_stdstring< std::basic_string<CharT, Traits, Alloc>, CharT* >
{
BOOST_STATIC_CONSTANT(bool, value = true );
};
template<typename CharT, typename Traits, typename Alloc>
struct is_char_array_to_stdstring< std::basic_string<CharT, Traits, Alloc>, const CharT* >
{
BOOST_STATIC_CONSTANT(bool, value = true );
};
template<typename Target, typename Source>
struct lexical_cast_do_cast
{
static inline Target lexical_cast_impl(const Source &arg)
{
typedef typename detail::array_to_pointer_decay<Source>::type src;
typedef typename detail::widest_char<
typename detail::stream_char<Target>::type
, typename detail::stream_char<src>::type
>::type char_type;
typedef detail::lcast_src_length<char_type, src> lcast_src_length;
std::size_t const src_len = lcast_src_length::value;
char_type buf[src_len + 1];
lcast_src_length::check_coverage();
return detail::lexical_cast<Target, src, !src_len>(arg, buf, src_len);
}
};
template<typename Source>
struct lexical_cast_copy
{
static inline Source lexical_cast_impl(const Source &arg)
{
return arg;
}
};
class precision_loss_error : public boost::numeric::bad_numeric_cast
{
public:
virtual const char * what() const throw()
{ return "bad numeric conversion: precision loss error"; }
};
template<class S >
struct throw_on_precision_loss
{
typedef boost::numeric::Trunc<S> Rounder;
typedef S source_type ;
typedef typename mpl::if_< is_arithmetic<S>,S,S const&>::type argument_type ;
static source_type nearbyint ( argument_type s )
{
source_type orig_div_round = s / Rounder::nearbyint(s);
if ( (orig_div_round > 1 ? orig_div_round - 1 : 1 - orig_div_round) > std::numeric_limits<source_type>::epsilon() )
BOOST_THROW_EXCEPTION( precision_loss_error() );
return s ;
}
typedef typename Rounder::round_style round_style;
} ;
template<typename Target, typename Source>
struct lexical_cast_dynamic_num_not_ignoring_minus
{
static inline Target lexical_cast_impl(const Source &arg)
{
try{
typedef boost::numeric::converter<
Target,
Source,
boost::numeric::conversion_traits<Target,Source>,
boost::numeric::def_overflow_handler,
throw_on_precision_loss<Source>
> Converter ;
return Converter::convert(arg);
} catch( ::boost::numeric::bad_numeric_cast const& ) {
BOOST_LCAST_THROW_BAD_CAST(Source, Target);
}
}
};
template<typename Target, typename Source>
struct lexical_cast_dynamic_num_ignoring_minus
{
static inline Target lexical_cast_impl(const Source &arg)
{
try{
typedef boost::numeric::converter<
Target,
Source,
boost::numeric::conversion_traits<Target,Source>,
boost::numeric::def_overflow_handler,
throw_on_precision_loss<Source>
> Converter ;
bool has_minus = ( arg < 0);
if ( has_minus ) {
return static_cast<Target>(-Converter::convert(-arg));
} else {
return Converter::convert(arg);
}
} catch( ::boost::numeric::bad_numeric_cast const& ) {
BOOST_LCAST_THROW_BAD_CAST(Source, Target);
}
}
};
/*
* lexical_cast_dynamic_num follows the rules:
* 1) If Source can be converted to Target without precision loss and
* without overflows, then assign Source to Target and return
*
* 2) If Source is less than 0 and Target is an unsigned integer,
* then negate Source, check the requirements of rule 1) and if
* successful, assign static_casted Source to Target and return
*
* 3) Otherwise throw a bad_lexical_cast exception
*
*
* Rule 2) required because boost::lexical_cast has the behavior of
* stringstream, which uses the rules of scanf for conversions. And
* in the C99 standard for unsigned input value minus sign is
* optional, so if a negative number is read, no errors will arise
* and the result will be the two's complement.
*/
template<typename Target, typename Source>
struct lexical_cast_dynamic_num
{
static inline Target lexical_cast_impl(const Source &arg)
{
typedef BOOST_DEDUCED_TYPENAME ::boost::mpl::if_c<
::boost::type_traits::ice_and<
::boost::type_traits::ice_or<
::boost::is_signed<Source>::value,
::boost::is_float<Source>::value
>::value,
::boost::type_traits::ice_not<
is_same<Source, bool>::value
>::value,
::boost::type_traits::ice_not<
is_same<Target, bool>::value
>::value,
::boost::is_unsigned<Target>::value
>::value,
lexical_cast_dynamic_num_ignoring_minus<Target, Source>,
lexical_cast_dynamic_num_not_ignoring_minus<Target, Source>
>::type caster_type;
return caster_type::lexical_cast_impl(arg);
}
};
}
template<typename Target, typename Source>
inline Target lexical_cast(const Source &arg)
{
typedef typename detail::array_to_pointer_decay<Source>::type src;
typedef BOOST_DEDUCED_TYPENAME detail::array_to_pointer_decay<Source>::type src;
typedef typename detail::widest_char<
typename detail::stream_char<Target>::type
, typename detail::stream_char<src>::type
>::type char_type;
typedef BOOST_DEDUCED_TYPENAME ::boost::type_traits::ice_or<
detail::is_xchar_to_xchar<Target, src>::value,
detail::is_char_array_to_stdstring<Target,src>::value,
::boost::type_traits::ice_and<
is_same<Target, src>::value,
detail::is_stdstring<Target>::value
>::value
> do_copy_type;
typedef detail::lcast_src_length<char_type, src> lcast_src_length;
std::size_t const src_len = lcast_src_length::value;
char_type buf[src_len + 1];
lcast_src_length::check_coverage();
return detail::lexical_cast<Target, src, !src_len>(arg, buf, src_len);
typedef BOOST_DEDUCED_TYPENAME
detail::is_arithmetic_and_not_xchars<Target, src> do_copy_with_dynamic_check_type;
typedef BOOST_DEDUCED_TYPENAME ::boost::mpl::if_c<
do_copy_type::value,
detail::lexical_cast_copy<src>,
BOOST_DEDUCED_TYPENAME ::boost::mpl::if_c<
do_copy_with_dynamic_check_type::value,
detail::lexical_cast_dynamic_num<Target, src>,
detail::lexical_cast_do_cast<Target, src>
>::type
>::type caster_type;
return caster_type::lexical_cast_impl(arg);
}
#else
@@ -1205,7 +1707,8 @@ namespace boost
}
// Copyright Kevlin Henney, 2000-2005.
// Copyright Alexander Nasonov, 2006-2007.
// Copyright Alexander Nasonov, 2006-2010.
// Copyright Antony Polukhin, 2011.
//
// Distributed under the Boost Software License, Version 1.0. (See
// accompanying file LICENSE_1_0.txt or copy at