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// ArduinoJson - arduinojson.org
// Copyright Benoit Blanchon 2014-2018
// MIT License
#pragma once
#include "../TypeTraits/FloatTraits.hpp"
#include "./ctype.hpp"
#include "./math.hpp"
namespace ArduinoJson {
namespace Internals {
template <typename T>
inline T parseFloat(const char* s) {
typedef FloatTraits<T> traits;
typedef typename traits::mantissa_type mantissa_t;
typedef typename traits::exponent_type exponent_t;
if (!s) return 0; // NULL
bool negative_result = false;
switch (*s) {
case '-':
negative_result = true;
s++;
break;
case '+':
s++;
break;
}
if (*s == 't') return 1; // true
if (*s == 'n' || *s == 'N') return traits::nan();
if (*s == 'i' || *s == 'I')
return negative_result ? -traits::inf() : traits::inf();
mantissa_t mantissa = 0;
exponent_t exponent_offset = 0;
while (isdigit(*s)) {
if (mantissa < traits::mantissa_max / 10)
mantissa = mantissa * 10 + (*s - '0');
else
exponent_offset++;
s++;
}
if (*s == '.') {
s++;
while (isdigit(*s)) {
if (mantissa < traits::mantissa_max / 10) {
mantissa = mantissa * 10 + (*s - '0');
exponent_offset--;
}
s++;
}
}
int exponent = 0;
if (*s == 'e' || *s == 'E') {
s++;
bool negative_exponent = false;
if (*s == '-') {
negative_exponent = true;
s++;
} else if (*s == '+') {
s++;
}
while (isdigit(*s)) {
exponent = exponent * 10 + (*s - '0');
if (exponent + exponent_offset > traits::exponent_max) {
if (negative_exponent)
return negative_result ? -0.0f : 0.0f;
else
return negative_result ? -traits::inf() : traits::inf();
}
s++;
}
if (negative_exponent) exponent = -exponent;
}
exponent += exponent_offset;
T result = traits::make_float(static_cast<T>(mantissa), exponent);
return negative_result ? -result : result;
}
}
}
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