From 907bced466c73679076b0b836f5f7339833179c4 Mon Sep 17 00:00:00 2001
From: bolero-MURAKAMI <bolero.murakami@gmail.com>
Date: Mon, 16 Apr 2012 11:21:40 +0900
Subject: [PATCH] add atof, strtof, strtod, strtold

---
 sprout/cstdlib/atof.hpp         |  17 +++
 sprout/cstdlib/conversion.hpp   |   5 +
 sprout/cstdlib/str_to_float.hpp | 255 ++++++++++++++++++++++++++++++++
 sprout/cstdlib/str_to_int.hpp   |   1 +
 sprout/cstdlib/strtod.hpp       |  26 ++++
 sprout/cstdlib/strtof.hpp       |  26 ++++
 sprout/cstdlib/strtold.hpp      |  26 ++++
 7 files changed, 356 insertions(+)
 create mode 100644 sprout/cstdlib/atof.hpp
 create mode 100644 sprout/cstdlib/str_to_float.hpp
 create mode 100644 sprout/cstdlib/strtod.hpp
 create mode 100644 sprout/cstdlib/strtof.hpp
 create mode 100644 sprout/cstdlib/strtold.hpp

diff --git a/sprout/cstdlib/atof.hpp b/sprout/cstdlib/atof.hpp
new file mode 100644
index 00000000..a2e7b9fa
--- /dev/null
+++ b/sprout/cstdlib/atof.hpp
@@ -0,0 +1,17 @@
+#ifndef SPROUT_CSTDLIB_ATOF_HPP
+#define SPROUT_CSTDLIB_ATOF_HPP
+
+#include <sprout/config.hpp>
+#include <sprout/cstdlib/str_to_float.hpp>
+
+namespace sprout {
+	//
+	// atof
+	//
+	template<typename Char>
+	inline SPROUT_CONSTEXPR double atof(Char const* str){
+		return sprout::str_to_float<double>(str);
+	}
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_CSTDLIB_ATOF_HPP
diff --git a/sprout/cstdlib/conversion.hpp b/sprout/cstdlib/conversion.hpp
index acde2a35..f1c3bc5d 100644
--- a/sprout/cstdlib/conversion.hpp
+++ b/sprout/cstdlib/conversion.hpp
@@ -4,12 +4,17 @@
 #include <sprout/config.hpp>
 #include <sprout/cstdlib/ascii_to_int.hpp>
 #include <sprout/cstdlib/str_to_int.hpp>
+#include <sprout/cstdlib/str_to_float.hpp>
 #include <sprout/cstdlib/atoi.hpp>
 #include <sprout/cstdlib/atol.hpp>
 #include <sprout/cstdlib/atoll.hpp>
+#include <sprout/cstdlib/atof.hpp>
 #include <sprout/cstdlib/strtol.hpp>
 #include <sprout/cstdlib/strtoul.hpp>
 #include <sprout/cstdlib/strtoll.hpp>
 #include <sprout/cstdlib/strtoull.hpp>
+#include <sprout/cstdlib/strtof.hpp>
+#include <sprout/cstdlib/strtod.hpp>
+#include <sprout/cstdlib/strtold.hpp>
 
 #endif	// #ifndef SPROUT_CSTDLIB_CONVERSION_HPP
diff --git a/sprout/cstdlib/str_to_float.hpp b/sprout/cstdlib/str_to_float.hpp
new file mode 100644
index 00000000..6a554fb6
--- /dev/null
+++ b/sprout/cstdlib/str_to_float.hpp
@@ -0,0 +1,255 @@
+#ifndef SPROUT_CSTDLIB_STR_TO_FLOAT_HPP
+#define SPROUT_CSTDLIB_STR_TO_FLOAT_HPP
+
+#include <cstddef>
+#include <cstdlib>
+#include <cmath>
+#include <limits>
+#include <sprout/config.hpp>
+#include <sprout/iterator/operation.hpp>
+#include <sprout/ctype/ascii.hpp>
+#include <sprout/utility/enabler_if.hpp>
+
+namespace sprout {
+	namespace detail {
+		template<typename FloatType, typename CStrIterator>
+		inline SPROUT_CONSTEXPR FloatType str_to_float_impl_scale(
+			CStrIterator str,
+			bool negative,
+			FloatType number = FloatType(),
+			std::size_t num_digits = 0,
+			std::size_t num_decimals = 0,
+			long exponent = 0,
+			long n = 0,
+			FloatType p10 = FloatType(10)
+			)
+		{
+			typedef typename std::iterator_traits<CStrIterator>::value_type char_type;
+			return n ? sprout::detail::str_to_float_impl_scale<FloatType>(
+					str,
+					negative,
+					n & 1 ? (exponent < 0 ? number / p10 : number * p10) : number,
+					num_digits,
+					num_decimals,
+					exponent,
+					n >> 1,
+					p10 * p10
+					)
+				: number
+				;
+		}
+		template<typename FloatType, typename CStrIterator>
+		inline SPROUT_CONSTEXPR FloatType str_to_float_impl_exponent_2(
+			CStrIterator str,
+			bool negative,
+			FloatType number = FloatType(),
+			std::size_t num_digits = 0,
+			std::size_t num_decimals = 0,
+			long exponent = 0,
+			long n = 0
+			)
+		{
+			typedef typename std::iterator_traits<CStrIterator>::value_type char_type;
+			return exponent >= std::numeric_limits<FloatType>::min_exponent
+				&& exponent <= std::numeric_limits<FloatType>::max_exponent
+				? sprout::detail::str_to_float_impl_scale<FloatType>(
+					str,
+					negative,
+					number,
+					num_digits,
+					num_decimals,
+					exponent,
+					exponent < 0 ? -exponent : exponent
+					)
+				: HUGE_VAL
+				;
+		}
+		template<typename FloatType, typename CStrIterator>
+		inline SPROUT_CONSTEXPR FloatType str_to_float_impl_exponent_1(
+			CStrIterator str,
+			bool negative,
+			FloatType number = FloatType(),
+			std::size_t num_digits = 0,
+			std::size_t num_decimals = 0,
+			long exponent = 0,
+			long n = 0
+			)
+		{
+			typedef typename std::iterator_traits<CStrIterator>::value_type char_type;
+			return sprout::ascii::isdigit(*str) ? sprout::detail::str_to_float_impl_exponent_1<FloatType>(
+					sprout::next(str),
+					negative,
+					number,
+					num_digits,
+					num_decimals,
+					exponent,
+					n * 10 + (*str - static_cast<char_type>('0'))
+					)
+				: sprout::detail::str_to_float_impl_exponent_2<FloatType>(
+					str,
+					negative,
+					number,
+					num_digits,
+					num_decimals,
+					negative ? exponent + n : exponent - n,
+					n
+					)
+				;
+		}
+		template<typename FloatType, typename CStrIterator>
+		inline SPROUT_CONSTEXPR FloatType str_to_float_impl_exponent(
+			CStrIterator str,
+			bool negative,
+			FloatType number = FloatType(),
+			std::size_t num_digits = 0,
+			std::size_t num_decimals = 0,
+			long exponent = 0
+			)
+		{
+			typedef typename std::iterator_traits<CStrIterator>::value_type char_type;
+			return (*str == static_cast<char_type>('e') || *str == static_cast<char_type>('E'))
+				? *sprout::next(str) == static_cast<char_type>('-')
+					? sprout::detail::str_to_float_impl_exponent_1<FloatType>(
+						sprout::next(str, 2),
+						true,
+						number,
+						num_digits,
+						num_decimals,
+						exponent
+						)
+					: sprout::detail::str_to_float_impl_exponent_1<FloatType>(
+						sprout::next(str, 2),
+						false,
+						number,
+						num_digits,
+						num_decimals,
+						exponent
+						)
+				: sprout::detail::str_to_float_impl_exponent_2<FloatType>(
+					str,
+					negative,
+					number,
+					num_digits,
+					num_decimals,
+					exponent
+					)
+				;
+		}
+		template<typename FloatType, typename CStrIterator>
+		inline SPROUT_CONSTEXPR FloatType str_to_float_impl_decimal_1(
+			CStrIterator str,
+			bool negative,
+			FloatType number = FloatType(),
+			std::size_t num_digits = 0,
+			std::size_t num_decimals = 0,
+			long exponent = 0
+			)
+		{
+			typedef typename std::iterator_traits<CStrIterator>::value_type char_type;
+			return num_digits == 0 ? FloatType()
+				: sprout::detail::str_to_float_impl_exponent<FloatType>(
+					str,
+					negative,
+					negative ? -number : number,
+					num_digits,
+					num_decimals,
+					exponent
+					)
+				;
+		}
+		template<typename FloatType, typename CStrIterator>
+		inline SPROUT_CONSTEXPR FloatType str_to_float_impl_decimal(
+			CStrIterator str,
+			bool negative,
+			FloatType number = FloatType(),
+			std::size_t num_digits = 0,
+			std::size_t num_decimals = 0,
+			long exponent = 0
+			)
+		{
+			typedef typename std::iterator_traits<CStrIterator>::value_type char_type;
+			return sprout::ascii::isdigit(*str) ? sprout::detail::str_to_float_impl_decimal<FloatType>(
+					sprout::next(str),
+					negative,
+					number * 10 + (*str - static_cast<char_type>('0')),
+					num_digits + 1,
+					num_decimals + 1,
+					exponent
+					)
+				: sprout::detail::str_to_float_impl_decimal_1<FloatType>(
+					str,
+					negative,
+					number,
+					num_digits,
+					num_decimals,
+					exponent - num_decimals
+					)
+				;
+		}
+
+		template<typename FloatType, typename CStrIterator>
+		inline SPROUT_CONSTEXPR FloatType str_to_float_impl(
+			CStrIterator str,
+			bool negative,
+			FloatType number = FloatType(),
+			std::size_t num_digits = 0
+			)
+		{
+			typedef typename std::iterator_traits<CStrIterator>::value_type char_type;
+			return sprout::ascii::isdigit(*str) ? sprout::detail::str_to_float_impl<FloatType>(
+					sprout::next(str),
+					negative,
+					number * 10 + (*str - static_cast<char_type>('0')),
+					num_digits + 1
+					)
+				: *str == static_cast<char_type>('.') ? sprout::detail::str_to_float_impl_decimal<FloatType>(
+					sprout::next(str),
+					negative,
+					number,
+					num_digits
+					)
+				: sprout::detail::str_to_float_impl_decimal_1<FloatType>(
+					str,
+					negative,
+					number,
+					num_digits
+					)
+				;
+		}
+		template<typename FloatType, typename CStrIterator>
+		inline SPROUT_CONSTEXPR FloatType str_to_float(CStrIterator str) {
+			return sprout::ascii::isspace(*str)
+				? sprout::detail::str_to_float<FloatType>(sprout::next(str))
+				: *str == static_cast<typename std::iterator_traits<CStrIterator>::value_type>('-')
+				? sprout::detail::str_to_float_impl<FloatType>(sprout::next(str), true)
+				: *str == static_cast<typename std::iterator_traits<CStrIterator>::value_type>('+')
+				? sprout::detail::str_to_float_impl<FloatType>(sprout::next(str), false)
+				: sprout::detail::str_to_float_impl<FloatType>(str, false)
+				;
+		}
+		template<typename FloatType, typename CStrIterator, typename CharPtr>
+		inline SPROUT_CONSTEXPR FloatType str_to_float(CStrIterator str, CharPtr* endptr) {
+			return !endptr ? sprout::detail::str_to_float<FloatType>(str)
+				: std::strtod(str, endptr)
+				;
+		}
+	}	// namespace detail
+
+	//
+	// str_to_float
+	//
+	template<typename FloatType, typename Char>
+	inline SPROUT_CONSTEXPR FloatType str_to_float(Char const* str, Char** endptr) {
+		return sprout::detail::str_to_float<FloatType>(str, endptr);
+	}
+	template<typename FloatType, typename Char>
+	inline SPROUT_CONSTEXPR FloatType str_to_float(Char const* str, std::nullptr_t endptr) {
+		return sprout::detail::str_to_float<FloatType>(str);
+	}
+	template<typename FloatType, typename Char>
+	inline SPROUT_CONSTEXPR FloatType str_to_float(Char const* str) {
+		return sprout::detail::str_to_float<FloatType>(str);
+	}
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_CSTDLIB_STR_TO_FLOAT_HPP
diff --git a/sprout/cstdlib/str_to_int.hpp b/sprout/cstdlib/str_to_int.hpp
index 784be7c0..5bf05d02 100644
--- a/sprout/cstdlib/str_to_int.hpp
+++ b/sprout/cstdlib/str_to_int.hpp
@@ -6,6 +6,7 @@
 #include <limits>
 #include <sprout/config.hpp>
 #include <sprout/iterator/operation.hpp>
+#include <sprout/ctype/ascii.hpp>
 #include <sprout/utility/enabler_if.hpp>
 #include <sprout/detail/char_conversion.hpp>
 
diff --git a/sprout/cstdlib/strtod.hpp b/sprout/cstdlib/strtod.hpp
new file mode 100644
index 00000000..23926cc1
--- /dev/null
+++ b/sprout/cstdlib/strtod.hpp
@@ -0,0 +1,26 @@
+#ifndef SPROUT_CSTDLIB_STRTOD_HPP
+#define SPROUT_CSTDLIB_STRTOD_HPP
+
+#include <cstddef>
+#include <sprout/config.hpp>
+#include <sprout/cstdlib/str_to_float.hpp>
+
+namespace sprout {
+	//
+	// strtod
+	//
+	template<typename Char>
+	inline SPROUT_CONSTEXPR double strtod(Char const* str, Char** endptr){
+		return sprout::str_to_float<double>(str, endptr);
+	}
+	template<typename Char>
+	inline SPROUT_CONSTEXPR double strtod(Char const* str, std::nullptr_t endptr){
+		return sprout::str_to_float<double>(str);
+	}
+	template<typename Char>
+	inline SPROUT_CONSTEXPR double strtod(Char const* str){
+		return sprout::str_to_float<double>(str);
+	}
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_CSTDLIB_STRTOD_HPP
diff --git a/sprout/cstdlib/strtof.hpp b/sprout/cstdlib/strtof.hpp
new file mode 100644
index 00000000..257e059a
--- /dev/null
+++ b/sprout/cstdlib/strtof.hpp
@@ -0,0 +1,26 @@
+#ifndef SPROUT_CSTDLIB_STRTOF_HPP
+#define SPROUT_CSTDLIB_STRTOF_HPP
+
+#include <cstddef>
+#include <sprout/config.hpp>
+#include <sprout/cstdlib/str_to_float.hpp>
+
+namespace sprout {
+	//
+	// strtof
+	//
+	template<typename Char>
+	inline SPROUT_CONSTEXPR float strtof(Char const* str, Char** endptr){
+		return sprout::str_to_float<float>(str, endptr);
+	}
+	template<typename Char>
+	inline SPROUT_CONSTEXPR float strtof(Char const* str, std::nullptr_t endptr){
+		return sprout::str_to_float<float>(str);
+	}
+	template<typename Char>
+	inline SPROUT_CONSTEXPR float strtof(Char const* str){
+		return sprout::str_to_float<float>(str);
+	}
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_CSTDLIB_STRTOF_HPP
diff --git a/sprout/cstdlib/strtold.hpp b/sprout/cstdlib/strtold.hpp
new file mode 100644
index 00000000..809ed27a
--- /dev/null
+++ b/sprout/cstdlib/strtold.hpp
@@ -0,0 +1,26 @@
+#ifndef SPROUT_CSTDLIB_STRTOLD_HPP
+#define SPROUT_CSTDLIB_STRTOLD_HPP
+
+#include <cstddef>
+#include <sprout/config.hpp>
+#include <sprout/cstdlib/str_to_float.hpp>
+
+namespace sprout {
+	//
+	// strtold
+	//
+	template<typename Char>
+	inline SPROUT_CONSTEXPR long double strtold(Char const* str, Char** endptr){
+		return sprout::str_to_float<long double>(str, endptr);
+	}
+	template<typename Char>
+	inline SPROUT_CONSTEXPR long double strtold(Char const* str, std::nullptr_t endptr){
+		return sprout::str_to_float<long double>(str);
+	}
+	template<typename Char>
+	inline SPROUT_CONSTEXPR long double strtold(Char const* str){
+		return sprout::str_to_float<long double>(str);
+	}
+}	// namespace sprout
+
+#endif	// #ifndef SPROUT_CSTDLIB_STRTOLD_HPP