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 *
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 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
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 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
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// minimal cmath

#pragma once

#include <cstdlib>
#include <inttypes.h>

#include <math.h>

#ifndef M_PI
#define M_PI 3.14159265358979323846
#endif

namespace std
{

#if !defined(FLT_EPSILON)
#define FLT_EPSILON     __FLT_EPSILON__
#endif


#ifdef isfinite
#undef isfinite
#endif  // isfinite

inline bool isfinite(float value) { return __builtin_isfinite(value); }
inline bool isfinite(double value) { return __builtin_isfinite(value); }
inline bool isfinite(long double value) { return __builtin_isfinite(value); }


#ifdef isnan
#undef isnan
#endif  // isnan

inline bool isnan(float value) { return __builtin_isnan(value); }
inline bool isnan(double value) { return __builtin_isnan(value); }
inline bool isnan(long double value) { return __builtin_isnan(value); }


#ifdef isinf
#undef isinf
#endif  // isinf

inline bool isinf(float value) { return __builtin_isinf_sign(value); }
inline bool isinf(double value) { return __builtin_isinf_sign(value); }
inline bool isinf(long double value) { return __builtin_isinf_sign(value); }

/*
 * NuttX has no usable C++ math library, so we need to provide the needed definitions here manually.
 */
#define NUTTX_WRAP_MATH_FUN_UNARY(name)                                   \
	inline float       name(float x)       { return ::name##f(x); }          \
	inline double      name(double x)      { return ::name(x); }             \
	inline long double name(long double x) { return ::name##l(x); }

#define NUTTX_WRAP_MATH_FUN_BINARY(name)                                                    \
	inline float       name(float x, float y)             { return ::name##f(x, y); }          \
	inline double      name(double x, double y)           { return ::name(x, y); }             \
	inline long double name(long double x, long double y) { return ::name##l(x, y); }

NUTTX_WRAP_MATH_FUN_UNARY(fabs)
NUTTX_WRAP_MATH_FUN_UNARY(log)
NUTTX_WRAP_MATH_FUN_UNARY(log10)
NUTTX_WRAP_MATH_FUN_UNARY(exp)
NUTTX_WRAP_MATH_FUN_UNARY(sqrt)
NUTTX_WRAP_MATH_FUN_UNARY(sin)
NUTTX_WRAP_MATH_FUN_UNARY(cos)
NUTTX_WRAP_MATH_FUN_UNARY(tan)
NUTTX_WRAP_MATH_FUN_UNARY(asin)
NUTTX_WRAP_MATH_FUN_UNARY(acos)
NUTTX_WRAP_MATH_FUN_UNARY(atan)
NUTTX_WRAP_MATH_FUN_UNARY(sinh)
NUTTX_WRAP_MATH_FUN_UNARY(cosh)
NUTTX_WRAP_MATH_FUN_UNARY(tanh)
NUTTX_WRAP_MATH_FUN_UNARY(ceil)
NUTTX_WRAP_MATH_FUN_UNARY(floor)

NUTTX_WRAP_MATH_FUN_BINARY(pow)
NUTTX_WRAP_MATH_FUN_BINARY(atan2)

}