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vn-verdnaturachat/ios/Pods/boost-for-react-native/boost/math/cstdfloat/cstdfloat_iostream.hpp

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///////////////////////////////////////////////////////////////////////////////
// Copyright Christopher Kormanyos 2014.
// Copyright John Maddock 2014.
// Copyright Paul Bristow 2014.
// Distributed under 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)
//
// Implement quadruple-precision I/O stream operations.
#ifndef _BOOST_CSTDFLOAT_IOSTREAM_2014_02_15_HPP_
#define _BOOST_CSTDFLOAT_IOSTREAM_2014_02_15_HPP_
#include <boost/math/cstdfloat/cstdfloat_types.hpp>
#include <boost/math/cstdfloat/cstdfloat_limits.hpp>
#include <boost/math/cstdfloat/cstdfloat_cmath.hpp>
#if defined(BOOST_CSTDFLOAT_NO_LIBQUADMATH_CMATH)
#error You can not use <boost/math/cstdfloat/cstdfloat_iostream.hpp> with BOOST_CSTDFLOAT_NO_LIBQUADMATH_CMATH defined.
#endif
#if defined(BOOST_CSTDFLOAT_HAS_INTERNAL_FLOAT128_T) && defined(BOOST_MATH_USE_FLOAT128) && !defined(BOOST_CSTDFLOAT_NO_LIBQUADMATH_SUPPORT)
#include <cstddef>
#include <istream>
#include <ostream>
#include <sstream>
#include <stdexcept>
#include <string>
#include <boost/static_assert.hpp>
#include <boost/throw_exception.hpp>
// #if (0)
#if defined(__GNUC__)
// Forward declarations of quadruple-precision string functions.
extern "C" int quadmath_snprintf(char *str, size_t size, const char *format, ...) throw();
extern "C" boost::math::cstdfloat::detail::float_internal128_t strtoflt128(const char*, char **) throw();
namespace std
{
template<typename char_type, class traits_type>
inline std::basic_ostream<char_type, traits_type>& operator<<(std::basic_ostream<char_type, traits_type>& os, const boost::math::cstdfloat::detail::float_internal128_t& x)
{
std::basic_ostringstream<char_type, traits_type> ostr;
ostr.flags(os.flags());
ostr.imbue(os.getloc());
ostr.precision(os.precision());
char my_buffer[64U];
const int my_prec = static_cast<int>(os.precision());
const int my_digits = ((my_prec == 0) ? 36 : my_prec);
const std::ios_base::fmtflags my_flags = os.flags();
char my_format_string[8U];
std::size_t my_format_string_index = 0U;
my_format_string[my_format_string_index] = '%';
++my_format_string_index;
if(my_flags & std::ios_base::showpos) { my_format_string[my_format_string_index] = '+'; ++my_format_string_index; }
if(my_flags & std::ios_base::showpoint) { my_format_string[my_format_string_index] = '#'; ++my_format_string_index; }
my_format_string[my_format_string_index + 0U] = '.';
my_format_string[my_format_string_index + 1U] = '*';
my_format_string[my_format_string_index + 2U] = 'Q';
my_format_string_index += 3U;
char the_notation_char;
if (my_flags & std::ios_base::scientific) { the_notation_char = 'e'; }
else if(my_flags & std::ios_base::fixed) { the_notation_char = 'f'; }
else { the_notation_char = 'g'; }
my_format_string[my_format_string_index + 0U] = the_notation_char;
my_format_string[my_format_string_index + 1U] = 0;
const int v = ::quadmath_snprintf(my_buffer,
static_cast<int>(sizeof(my_buffer)),
my_format_string,
my_digits,
x);
if(v < 0) { BOOST_THROW_EXCEPTION(std::runtime_error("Formatting of boost::float128_t failed internally in quadmath_snprintf().")); }
if(v >= static_cast<int>(sizeof(my_buffer) - 1U))
{
// Evidently there is a really long floating-point string here,
// such as a small decimal representation in non-scientific notation.
// So we have to use dynamic memory allocation for the output
// string buffer.
char* my_buffer2 = static_cast<char*>(0U);
#ifndef BOOST_NO_EXCEPTIONS
try
{
#endif
my_buffer2 = new char[v + 3];
#ifndef BOOST_NO_EXCEPTIONS
}
catch(const std::bad_alloc&)
{
BOOST_THROW_EXCEPTION(std::runtime_error("Formatting of boost::float128_t failed while allocating memory."));
}
#endif
const int v2 = ::quadmath_snprintf(my_buffer2,
v + 3,
my_format_string,
my_digits,
x);
if(v2 >= v + 3)
{
BOOST_THROW_EXCEPTION(std::runtime_error("Formatting of boost::float128_t failed."));
}
static_cast<void>(ostr << my_buffer2);
delete [] my_buffer2;
}
else
{
static_cast<void>(ostr << my_buffer);
}
return (os << ostr.str());
}
template<typename char_type, class traits_type>
inline std::basic_istream<char_type, traits_type>& operator>>(std::basic_istream<char_type, traits_type>& is, boost::math::cstdfloat::detail::float_internal128_t& x)
{
std::string str;
static_cast<void>(is >> str);
char* p_end;
x = strtoflt128(str.c_str(), &p_end);
if(static_cast<std::ptrdiff_t>(p_end - str.c_str()) != static_cast<std::ptrdiff_t>(str.length()))
{
for(std::string::const_reverse_iterator it = str.rbegin(); it != str.rend(); ++it)
{
static_cast<void>(is.putback(*it));
}
is.setstate(ios_base::failbit);
BOOST_THROW_EXCEPTION(std::runtime_error("Unable to interpret input string as a boost::float128_t"));
}
return is;
}
}
// #elif defined(__GNUC__)
#elif defined(BOOST_INTEL)
// The section for I/O stream support for the ICC compiler is particularly
// long, because these functions must be painstakingly synthesized from
// manually-written routines (ICC does not support I/O stream operations
// for its _Quad type).
// The following string-extraction routines are based on the methodology
// used in Boost.Multiprecision by John Maddock and Christopher Kormanyos.
// This methodology has been slightly modified here for boost::float128_t.
#include <cstring>
#include <cctype>
#include <boost/lexical_cast.hpp>
namespace boost { namespace math { namespace cstdfloat { namespace detail {
template<class string_type>
void format_float_string(string_type& str,
int my_exp,
int digits,
const std::ios_base::fmtflags f,
const bool iszero)
{
typedef typename string_type::size_type size_type;
const bool scientific = ((f & std::ios_base::scientific) == std::ios_base::scientific);
const bool fixed = ((f & std::ios_base::fixed) == std::ios_base::fixed);
const bool showpoint = ((f & std::ios_base::showpoint) == std::ios_base::showpoint);
const bool showpos = ((f & std::ios_base::showpos) == std::ios_base::showpos);
const bool b_neg = ((str.size() != 0U) && (str[0] == '-'));
if(b_neg)
{
str.erase(0, 1);
}
if(digits == 0)
{
digits = static_cast<int>((std::max)(str.size(), size_type(16)));
}
if(iszero || str.empty() || (str.find_first_not_of('0') == string_type::npos))
{
// We will be printing zero, even though the value might not
// actually be zero (it just may have been rounded to zero).
str = "0";
if(scientific || fixed)
{
str.append(1, '.');
str.append(size_type(digits), '0');
if(scientific)
{
str.append("e+00");
}
}
else
{
if(showpoint)
{
str.append(1, '.');
if(digits > 1)
{
str.append(size_type(digits - 1), '0');
}
}
}
if(b_neg)
{
str.insert(0U, 1U, '-');
}
else if(showpos)
{
str.insert(0U, 1U, '+');
}
return;
}
if(!fixed && !scientific && !showpoint)
{
// Suppress trailing zeros.
typename string_type::iterator pos = str.end();
while(pos != str.begin() && *--pos == '0') { ; }
if(pos != str.end())
{
++pos;
}
str.erase(pos, str.end());
if(str.empty())
{
str = '0';
}
}
else if(!fixed || (my_exp >= 0))
{
// Pad out the end with zero's if we need to.
int chars = static_cast<int>(str.size());
chars = digits - chars;
if(scientific)
{
++chars;
}
if(chars > 0)
{
str.append(static_cast<size_type>(chars), '0');
}
}
if(fixed || (!scientific && (my_exp >= -4) && (my_exp < digits)))
{
if((1 + my_exp) > static_cast<int>(str.size()))
{
// Just pad out the end with zeros.
str.append(static_cast<size_type>((1 + my_exp) - static_cast<int>(str.size())), '0');
if(showpoint || fixed)
{
str.append(".");
}
}
else if(my_exp + 1 < static_cast<int>(str.size()))
{
if(my_exp < 0)
{
str.insert(0U, static_cast<size_type>(-1 - my_exp), '0');
str.insert(0U, "0.");
}
else
{
// Insert the decimal point:
str.insert(static_cast<size_type>(my_exp + 1), 1, '.');
}
}
else if(showpoint || fixed) // we have exactly the digits we require to left of the point
{
str += ".";
}
if(fixed)
{
// We may need to add trailing zeros.
int l = static_cast<int>(str.find('.') + 1U);
l = digits - (static_cast<int>(str.size()) - l);
if(l > 0)
{
str.append(size_type(l), '0');
}
}
}
else
{
// Scientific format:
if(showpoint || (str.size() > 1))
{
str.insert(1U, 1U, '.');
}
str.append(1U, 'e');
string_type e = boost::lexical_cast<string_type>(std::abs(my_exp));
if(e.size() < 2U)
{
e.insert(0U, 2U - e.size(), '0');
}
if(my_exp < 0)
{
e.insert(0U, 1U, '-');
}
else
{
e.insert(0U, 1U, '+');
}
str.append(e);
}
if(b_neg)
{
str.insert(0U, 1U, '-');
}
else if(showpos)
{
str.insert(0U, 1U, '+');
}
}
template<class float_type, class type_a> inline void eval_convert_to(type_a* pa, const float_type& cb) { *pa = static_cast<type_a>(cb); }
template<class float_type, class type_a> inline void eval_add (float_type& b, const type_a& a) { b += a; }
template<class float_type, class type_a> inline void eval_subtract (float_type& b, const type_a& a) { b -= a; }
template<class float_type, class type_a> inline void eval_multiply (float_type& b, const type_a& a) { b *= a; }
template<class float_type> inline void eval_multiply (float_type& b, const float_type& cb, const float_type& cb2) { b = (cb * cb2); }
template<class float_type, class type_a> inline void eval_divide (float_type& b, const type_a& a) { b /= a; }
template<class float_type> inline void eval_log10 (float_type& b, const float_type& cb) { b = std::log10(cb); }
template<class float_type> inline void eval_floor (float_type& b, const float_type& cb) { b = std::floor(cb); }
inline void round_string_up_at(std::string& s, int pos, int& expon)
{
// This subroutine rounds up a string representation of a
// number at the given position pos.
if(pos < 0)
{
s.insert(0U, 1U, '1');
s.erase(s.size() - 1U);
++expon;
}
else if(s[pos] == '9')
{
s[pos] = '0';
round_string_up_at(s, pos - 1, expon);
}
else
{
if((pos == 0) && (s[pos] == '0') && (s.size() == 1))
{
++expon;
}
++s[pos];
}
}
template<class float_type>
std::string convert_to_string(float_type& x,
std::streamsize digits,
const std::ios_base::fmtflags f)
{
const bool isneg = (x < 0);
const bool iszero = ((!isneg) ? bool(+x < (std::numeric_limits<float_type>::min)())
: bool(-x < (std::numeric_limits<float_type>::min)()));
const bool isnan = (x != x);
const bool isinf = ((!isneg) ? bool(+x > (std::numeric_limits<float_type>::max)())
: bool(-x > (std::numeric_limits<float_type>::max)()));
int expon = 0;
if(digits <= 0) { digits = std::numeric_limits<float_type>::max_digits10; }
const int org_digits = static_cast<int>(digits);
std::string result;
if(iszero)
{
result = "0";
}
else if(isinf)
{
if(x < 0)
{
return "-inf";
}
else
{
return ((f & std::ios_base::showpos) == std::ios_base::showpos) ? "+inf" : "inf";
}
}
else if(isnan)
{
return "nan";
}
else
{
// Start by figuring out the base-10 exponent.
if(isneg) { x = -x; }
float_type t;
float_type ten = 10;
eval_log10(t, x);
eval_floor(t, t);
eval_convert_to(&expon, t);
if(-expon > std::numeric_limits<float_type>::max_exponent10 - 3)
{
int e = -expon / 2;
const float_type t2 = boost::math::cstdfloat::detail::pown(ten, e);
eval_multiply(t, t2, x);
eval_multiply(t, t2);
if((expon & 1) != 0)
{
eval_multiply(t, ten);
}
}
else
{
t = boost::math::cstdfloat::detail::pown(ten, -expon);
eval_multiply(t, x);
}
// Make sure that the value lies between [1, 10), and adjust if not.
if(t < 1)
{
eval_multiply(t, 10);
--expon;
}
else if(t >= 10)
{
eval_divide(t, 10);
++expon;
}
float_type digit;
int cdigit;
// Adjust the number of digits required based on formatting options.
if(((f & std::ios_base::fixed) == std::ios_base::fixed) && (expon != -1))
{
digits += (expon + 1);
}
if((f & std::ios_base::scientific) == std::ios_base::scientific)
{
++digits;
}
// Extract the base-10 digits one at a time.
for(int i = 0; i < digits; ++i)
{
eval_floor(digit, t);
eval_convert_to(&cdigit, digit);
result += static_cast<char>('0' + cdigit);
eval_subtract(t, digit);
eval_multiply(t, ten);
}
// Possibly round the result.
if(digits >= 0)
{
eval_floor(digit, t);
eval_convert_to(&cdigit, digit);
eval_subtract(t, digit);
if((cdigit == 5) && (t == 0))
{
// Use simple bankers rounding.
if((static_cast<int>(*result.rbegin() - '0') & 1) != 0)
{
round_string_up_at(result, static_cast<int>(result.size() - 1U), expon);
}
}
else if(cdigit >= 5)
{
round_string_up_at(result, static_cast<int>(result.size() - 1), expon);
}
}
}
while((result.size() > static_cast<std::string::size_type>(digits)) && result.size())
{
// We may get here as a result of rounding.
if(result.size() > 1U)
{
result.erase(result.size() - 1U);
}
else
{
if(expon > 0)
{
--expon; // so we put less padding in the result.
}
else
{
++expon;
}
++digits;
}
}
if(isneg)
{
result.insert(0U, 1U, '-');
}
format_float_string(result, expon, org_digits, f, iszero);
return result;
}
template <class float_type>
bool convert_from_string(float_type& value, const char* p)
{
value = 0;
if((p == static_cast<const char*>(0U)) || (*p == static_cast<char>(0)))
{
return;
}
bool is_neg = false;
bool is_neg_expon = false;
BOOST_CONSTEXPR_OR_CONST int ten = 10;
int expon = 0;
int digits_seen = 0;
BOOST_CONSTEXPR_OR_CONST int max_digits = std::numeric_limits<float_type>::max_digits10 + 1;
if(*p == static_cast<char>('+'))
{
++p;
}
else if(*p == static_cast<char>('-'))
{
is_neg = true;
++p;
}
const bool isnan = ((std::strcmp(p, "nan") == 0) || (std::strcmp(p, "NaN") == 0) || (std::strcmp(p, "NAN") == 0));
if(isnan)
{
eval_divide(value, 0);
if(is_neg)
{
value = -value;
}
return true;
}
const bool isinf = ((std::strcmp(p, "inf") == 0) || (std::strcmp(p, "Inf") == 0) || (std::strcmp(p, "INF") == 0));
if(isinf)
{
value = 1;
eval_divide(value, 0);
if(is_neg)
{
value = -value;
}
return true;
}
// Grab all the leading digits before the decimal point.
while(std::isdigit(*p))
{
eval_multiply(value, ten);
eval_add(value, static_cast<int>(*p - '0'));
++p;
++digits_seen;
}
if(*p == static_cast<char>('.'))
{
// Grab everything after the point, stop when we've seen
// enough digits, even if there are actually more available.
++p;
while(std::isdigit(*p))
{
eval_multiply(value, ten);
eval_add(value, static_cast<int>(*p - '0'));
++p;
--expon;
if(++digits_seen > max_digits)
{
break;
}
}
while(std::isdigit(*p))
{
++p;
}
}
// Parse the exponent.
if((*p == static_cast<char>('e')) || (*p == static_cast<char>('E')))
{
++p;
if(*p == static_cast<char>('+'))
{
++p;
}
else if(*p == static_cast<char>('-'))
{
is_neg_expon = true;
++p;
}
int e2 = 0;
while(std::isdigit(*p))
{
e2 *= 10;
e2 += (*p - '0');
++p;
}
if(is_neg_expon)
{
e2 = -e2;
}
expon += e2;
}
if(expon)
{
// Scale by 10^expon. Note that 10^expon can be outside the range
// of our number type, even though the result is within range.
// If that looks likely, then split the calculation in two parts.
float_type t;
t = ten;
if(expon > (std::numeric_limits<float_type>::min_exponent10 + 2))
{
t = boost::math::cstdfloat::detail::pown(t, expon);
eval_multiply(value, t);
}
else
{
t = boost::math::cstdfloat::detail::pown(t, (expon + digits_seen + 1));
eval_multiply(value, t);
t = ten;
t = boost::math::cstdfloat::detail::pown(t, (-digits_seen - 1));
eval_multiply(value, t);
}
}
if(is_neg)
{
value = -value;
}
return (*p == static_cast<char>(0));
}
} } } } // boost::math::cstdfloat::detail
namespace std
{
template<typename char_type, class traits_type>
inline std::basic_ostream<char_type, traits_type>& operator<<(std::basic_ostream<char_type, traits_type>& os, const boost::math::cstdfloat::detail::float_internal128_t& x)
{
boost::math::cstdfloat::detail::float_internal128_t non_const_x = x;
const std::string str = boost::math::cstdfloat::detail::convert_to_string(non_const_x,
os.precision(),
os.flags());
std::basic_ostringstream<char_type, traits_type> ostr;
ostr.flags(os.flags());
ostr.imbue(os.getloc());
ostr.precision(os.precision());
static_cast<void>(ostr << str);
return (os << ostr.str());
}
template<typename char_type, class traits_type>
inline std::basic_istream<char_type, traits_type>& operator>>(std::basic_istream<char_type, traits_type>& is, boost::math::cstdfloat::detail::float_internal128_t& x)
{
std::string str;
static_cast<void>(is >> str);
const bool conversion_is_ok = boost::math::cstdfloat::detail::convert_from_string(x, str.c_str());
if(false == conversion_is_ok)
{
for(std::string::const_reverse_iterator it = str.rbegin(); it != str.rend(); ++it)
{
static_cast<void>(is.putback(*it));
}
is.setstate(ios_base::failbit);
BOOST_THROW_EXCEPTION(std::runtime_error("Unable to interpret input string as a boost::float128_t"));
}
return is;
}
}
#endif // Use __GNUC__ or BOOST_INTEL libquadmath
#endif // Not BOOST_CSTDFLOAT_NO_LIBQUADMATH_SUPPORT (i.e., the user would like to have libquadmath support)
#endif // _BOOST_CSTDFLOAT_IOSTREAM_2014_02_15_HPP_
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