/usr/include/boost/convert/strtol.hpp is in libboost1.65-dev 1.65.1+dfsg-0ubuntu5.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 | // Copyright (c) 2009-2016 Vladimir Batov.
// Use, modification and distribution are subject to the Boost Software License,
// Version 1.0. See http://www.boost.org/LICENSE_1_0.txt.
#ifndef BOOST_CONVERT_STRTOL_CONVERTER_HPP
#define BOOST_CONVERT_STRTOL_CONVERTER_HPP
#include <boost/convert/base.hpp>
#include <boost/type_traits/make_unsigned.hpp>
#include <boost/type_traits/is_same.hpp>
#include <boost/math/special_functions/round.hpp>
#include <limits>
#include <cmath>
#include <cstdlib>
#include <climits>
#if __GNUC__ == 4 && __GNUC_MINOR__ <= 2
namespace std
{
using ::strtold; // Tests indicated that gcc-4.2.1 does not have 'std::strtold'
}
#endif
namespace boost { namespace cnv
{
struct strtol;
}}
/// @brief std::strtol-based extended converter
/// @details The converter offers a fairly decent overall performance and moderate formatting facilities.
struct boost::cnv::strtol : public boost::cnv::cnvbase<boost::cnv::strtol>
{
typedef boost::cnv::strtol this_type;
typedef boost::cnv::cnvbase<this_type> base_type;
using base_type::operator();
private:
friend struct boost::cnv::cnvbase<this_type>;
template<typename string_type> void str_to(cnv::range<string_type> v, optional< int_type>& r) const { str_to_i (v, r); }
template<typename string_type> void str_to(cnv::range<string_type> v, optional< sint_type>& r) const { str_to_i (v, r); }
template<typename string_type> void str_to(cnv::range<string_type> v, optional< lint_type>& r) const { str_to_i (v, r); }
template<typename string_type> void str_to(cnv::range<string_type> v, optional< llint_type>& r) const { str_to_i (v, r); }
template<typename string_type> void str_to(cnv::range<string_type> v, optional< uint_type>& r) const { str_to_i (v, r); }
template<typename string_type> void str_to(cnv::range<string_type> v, optional< usint_type>& r) const { str_to_i (v, r); }
template<typename string_type> void str_to(cnv::range<string_type> v, optional< ulint_type>& r) const { str_to_i (v, r); }
template<typename string_type> void str_to(cnv::range<string_type> v, optional<ullint_type>& r) const { str_to_i (v, r); }
template<typename string_type> void str_to(cnv::range<string_type> v, optional< flt_type>& r) const { str_to_d (v, r); }
template<typename string_type> void str_to(cnv::range<string_type> v, optional< dbl_type>& r) const { str_to_d (v, r); }
template<typename string_type> void str_to(cnv::range<string_type> v, optional< ldbl_type>& r) const { str_to_d (v, r); }
template <typename char_type> cnv::range<char_type*> to_str ( int_type v, char_type* buf) const { return i_to_str(v, buf); }
template <typename char_type> cnv::range<char_type*> to_str ( uint_type v, char_type* buf) const { return i_to_str(v, buf); }
template <typename char_type> cnv::range<char_type*> to_str ( lint_type v, char_type* buf) const { return i_to_str(v, buf); }
template <typename char_type> cnv::range<char_type*> to_str ( ulint_type v, char_type* buf) const { return i_to_str(v, buf); }
template <typename char_type> cnv::range<char_type*> to_str ( llint_type v, char_type* buf) const { return i_to_str(v, buf); }
template <typename char_type> cnv::range<char_type*> to_str (ullint_type v, char_type* buf) const { return i_to_str(v, buf); }
template <typename char_type> cnv::range<char_type*> to_str ( dbl_type v, char_type* buf) const;
template<typename char_type, typename in_type> cnv::range<char_type*> i_to_str (in_type, char_type*) const;
template<typename string_type, typename out_type> void str_to_i (cnv::range<string_type>, optional<out_type>&) const;
template<typename string_type, typename out_type> void str_to_d (cnv::range<string_type>, optional<out_type>&) const;
static double adjust_fraction (double, int);
static int get_char (int v) { return (v < 10) ? (v += '0') : (v += 'A' - 10); }
};
template<typename char_type, typename Type>
boost::cnv::range<char_type*>
boost::cnv::strtol::i_to_str(Type in_value, char_type* buf) const
{
// C1. Base=10 optimization improves performance 10%
typedef typename boost::make_unsigned<Type>::type unsigned_type;
char_type* beg = buf + bufsize_ / 2;
char_type* end = beg;
bool const is_neg = std::is_signed<Type>::value && in_value < 0;
unsigned_type value = static_cast<unsigned_type>(is_neg ? -in_value : in_value);
if (base_ == 10) for (; value; *(--beg) = int(value % 10) + '0', value /= 10); //C1
else for (; value; *(--beg) = get_char(value % base_), value /= base_);
if (beg == end) *(--beg) = '0';
if (is_neg) *(--beg) = '-';
return cnv::range<char_type*>(beg, end);
}
inline
double
boost::cnv::strtol::adjust_fraction(double fraction, int precision)
{
// C1. Bring forward the fraction coming right after precision digits.
// That is, say, fraction=0.234567, precision=2. Then brought forward=23.4567
// C3. INT_MAX(4bytes)=2,147,483,647. So, 10^8 seems appropriate. If not, drop it down to 4.
// C4. ::round() returns the integral value that is nearest to x,
// with halfway cases rounded away from zero. Therefore,
// round( 0.4) = 0
// round( 0.5) = 1
// round( 0.6) = 1
// round(-0.4) = 0
// round(-0.5) = -1
// round(-0.6) = -1
int const tens[] = { 1, 10, 100, 1000, 10000, 100000, 1000000, 10000000 };
for (int k = precision / 8; k; --k) fraction *= 100000000; //C3.
fraction *= tens[precision % 8]; //C1
// return ::rint(fraction); //C4
return boost::math::round(fraction); //C4
}
template <typename char_type>
inline
boost::cnv::range<char_type*>
boost::cnv::strtol::to_str(double value, char_type* buf) const
{
char_type* beg = buf + bufsize_ / 2;
char_type* end = beg;
char_type* ipos = end - 1;
bool const is_negative = (value < 0) ? (value = -value, true) : false;
double ipart = std::floor(value);
double fpart = adjust_fraction(value - ipart, precision_);
int precision = precision_;
int const base = 10;
for (; 1 <= ipart; ipart /= base)
*(--beg) = get_char(int(ipart - std::floor(ipart / base) * base));
if (beg == end) *(--beg) = '0';
if (precision) *(end++) = '.';
for (char_type* fpos = end += precision; precision; --precision, fpart /= base)
*(--fpos) = get_char(int(fpart - std::floor(fpart / base) * base));
if (1 <= fpart)
{
for (; beg <= ipos; --ipos)
if (*ipos == '9') *ipos = '0';
else { ++*ipos; break; }
if (ipos < beg)
*(beg = ipos) = '1';
}
if (is_negative) *(--beg) = '-';
return cnv::range<char_type*>(beg, end);
}
template<typename string_type, typename out_type>
void
boost::cnv::strtol::str_to_i(cnv::range<string_type> range, boost::optional<out_type>& result_out) const
{
typedef typename boost::make_unsigned<out_type>::type unsigned_type;
typedef cnv::range<string_type> range_type;
typedef typename range_type::iterator iterator;
iterator s = range.begin();
unsigned int ch = *s;
bool const is_negative = ch == '-' ? (ch = *++s, true) : ch == '+' ? (ch = *++s, false) : false;
bool const is_unsigned = boost::is_same<out_type, unsigned_type>::value;
unsigned int base = base_;
/**/ if (is_negative && is_unsigned) return;
else if ((base == 0 || base == 16) && ch == '0' && (*++s == 'x' || *s == 'X')) ++s, base = 16;
else if (base == 0) base = ch == '0' ? (++s, 8) : 10;
unsigned_type const max = (std::numeric_limits<out_type>::max)() + (is_negative ? 1 : 0);
unsigned_type const cutoff = max / base;
unsigned int const cutlim = max % base;
unsigned_type result = 0;
for (; s != range.sentry(); ++s)
{
ch = *s;
/**/ if (std::isdigit(ch)) ch -= '0';
else if (std::isalpha(ch)) ch -= (std::isupper(ch) ? 'A' : 'a') - 10;
else return;
if (base <= ch || cutoff < result || (result == cutoff && cutlim < ch))
return;
result *= base;
result += ch;
}
result_out = is_negative ? -out_type(result) : out_type(result);
}
template<typename string_type, typename out_type>
void
boost::cnv::strtol::str_to_d(cnv::range<string_type> range, optional<out_type>& result_out) const
{
// C1. Because of strtold() currently only works with 'char'
// C2. strtold() does not work with ranges.
// Consequently, we have to copy the supplied range into a string for strtold().
// C3. Check if the end-of-string was reached -- *cnv_end == 0.
typedef cnv::range<string_type> range_type;
typedef typename range_type::value_type ch_type;
size_t const sz = 128;
ch_type str[sz] = {0}; std::strncpy(str, &*range.begin(), std::min(sz - 1, range.size()));
char* cnv_end = 0;
ldbl_type result = strtold(str, &cnv_end);
bool good = result != -HUGE_VALL && result != HUGE_VALL && *cnv_end == 0; //C3
out_type max = (std::numeric_limits<out_type>::max)();
if (good && -max <= result && result <= max)
result_out = out_type(result);
}
#endif // BOOST_CONVERT_STRTOL_CONVERTER_HPP
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