#ifndef _MATH_H
#define _MATH_H 1

// https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/math.h.html

#include <sys/cdefs.h>

__BEGIN_DECLS

#ifndef FLT_EVAL_METHOD
	#define FLT_EVAL_METHOD 0
#endif

#if FLT_EVAL_METHOD == 0
	typedef float float_t;
	typedef double double_t;
#elif FLT_EVAL_METHOD == 1
	typedef double float_t;
	typedef double double_t;
#elif FLT_EVAL_METHOD == 2
	typedef long double float_t;
	typedef long double double_t;
#endif

// FIXME: define this
// int fpclassify(real-floating x);

#define isfinite(x)				__builtin_isfinite(x)
#define isgreater(x, y)			__builtin_isgreater(x, y)
#define isgreaterequal(x, y)	__builtin_isgreaterequal(x, y)
#define isinf(x)				__builtin_isinf_sign(x)
#define isless(x, y)			__builtin_isless(x, y)
#define islessequal(x, y)		__builtin_islessequal(x, y)
#define islessgreater(x, y)		__builtin_islessgreater(x, y)
#define isnan(x)				__builtin_isnan(x)
#define isnormal(x)				__builtin_isnormal(x)
#define isunordered(x, y)		__builtin_isunordered(x, y)
#define signbit(x)				__builtin_signbit(x)

#define M_E			2.7182818284590452354
#define M_LOG2E		1.4426950408889634074
#define M_LOG10E	0.43429448190325182765
#define M_LN2		0.69314718055994530942
#define M_LN10		2.30258509299404568402
#define M_PI		3.14159265358979323846
#define M_PI_2		1.57079632679489661923
#define M_PI_4		0.78539816339744830962
#define M_1_PI		0.31830988618379067154
#define M_2_PI		0.63661977236758134308
#define M_2_SQRTPI	1.12837916709551257390
#define M_SQRT2		1.41421356237309504880
#define M_SQRT1_2	0.70710678118654752440

#define HUGE_VAL	__builtin_huge_val()
#define HUGE_VALF	__builtin_huge_valf()
#define HUGE_VALL	__builtin_huge_vall()
#define INFINITY	__builtin_inff()
#define NAN			__builtin_nanf("")

#define FP_INFINITE		0
#define FP_NAN			1
#define FP_NORMAL		2
#define FP_SUBNORMAL	3
#define FP_ZERO			4

#define FP_ILOGB0	-2147483647
#define FP_ILOGBNAN	+2147483647

#define MATH_ERRNO		1
#define MATH_ERREXCEPT	2

#define math_errhandling (MATH_ERRNO | MATH_ERREXCEPT)

double		acos(double);
float		acosf(float);
double		acosh(double);
float		acoshf(float);
long double acoshl(long double);
long double acosl(long double);
double		asin(double);
float		asinf(float);
double		asinh(double);
float		asinhf(float);
long double asinhl(long double);
long double asinl(long double);
double		atan(double);
double		atan2(double, double);
float		atan2f(float, float);
long double atan2l(long double, long double);
float		atanf(float);
double		atanh(double);
float		atanhf(float);
long double atanhl(long double);
long double atanl(long double);
double		cbrt(double);
float		cbrtf(float);
long double cbrtl(long double);
double		ceil(double);
float		ceilf(float);
long double ceill(long double);
double		copysign(double, double);
float		copysignf(float, float);
long double copysignl(long double, long double);
double		cos(double);
float		cosf(float);
double		cosh(double);
float		coshf(float);
long double coshl(long double);
long double cosl(long double);
double		erf(double);
double		erfc(double);
float		erfcf(float);
long double erfcl(long double);
float		erff(float);
long double erfl(long double);
double		exp(double);
double		exp2(double);
float		exp2f(float);
long double exp2l(long double);
float		expf(float);
long double expl(long double);
double		expm1(double);
float		expm1f(float);
long double expm1l(long double);
double		fabs(double);
float		fabsf(float);
long double fabsl(long double);
double		fdim(double, double);
float		fdimf(float, float);
long double fdiml(long double, long double);
double		floor(double);
float		floorf(float);
long double floorl(long double);
double		fma(double, double, double);
float		fmaf(float, float, float);
long double fmal(long double, long double, long double);
double		fmax(double, double);
float		fmaxf(float, float);
long double fmaxl(long double, long double);
double		fmin(double, double);
float		fminf(float, float);
long double fminl(long double, long double);
double		fmod(double, double);
float		fmodf(float, float);
long double fmodl(long double, long double);
double		frexp(double, int*);
float		frexpf(float, int*);
long double frexpl(long double, int*);
double		hypot(double, double);
float		hypotf(float, float);
long double hypotl(long double, long double);
int			ilogb(double);
int			ilogbf(float);
int			ilogbl(long double);
double		j0(double);
double		j1(double);
double		jn(int, double);
double		ldexp(double, int);
float		ldexpf(float, int);
long double ldexpl(long double, int);
double		lgamma(double);
float		lgammaf(float);
long double lgammal(long double);
long long	llrint(double);
long long	llrintf(float);
long long	llrintl(long double);
long long	llround(double);
long long	llroundf(float);
long long	llroundl(long double);
double		log(double);
double		log10(double);
float		log10f(float);
long double log10l(long double);
double		log1p(double);
float		log1pf(float);
long double log1pl(long double);
double		log2(double);
float		log2f(float);
long double log2l(long double);
double		logb(double);
float		logbf(float);
long double logbl(long double);
float		logf(float);
long double logl(long double);
long		lrint(double);
long		lrintf(float);
long		lrintl(long double);
long		lround(double);
long		lroundf(float);
long		lroundl(long double);
double		modf(double, double*);
float		modff(float, float*);
long double modfl(long double, long double*);
double		nan(const char*);
float		nanf(const char*);
long double nanl(const char*);
double		nearbyint(double);
float		nearbyintf(float);
long double nearbyintl(long double);
double		nextafter(double, double);
float		nextafterf(float, float);
long double nextafterl(long double, long double);
double		nexttoward(double, long double);
float		nexttowardf(float, long double);
long double nexttowardl(long double, long double);
double		pow(double, double);
float		powf(float, float);
long double powl(long double, long double);
double		remainder(double, double);
float		remainderf(float, float);
long double remainderl(long double, long double);
double		remquo(double, double, int*);
float		remquof(float, float, int*);
long double remquol(long double, long double, int*);
double		rint(double);
float		rintf(float);
long double rintl(long double);
double		round(double);
float		roundf(float);
long double roundl(long double);
double		scalbln(double, long);
float		scalblnf(float, long);
long double scalblnl(long double, long);
double		scalbn(double, int);
float		scalbnf(float, int);
long double scalbnl(long double, int);
double		sin(double);
float		sinf(float);
double		sinh(double);
float		sinhf(float);
long double sinhl(long double);
long double sinl(long double);
double		sqrt(double);
float		sqrtf(float);
long double sqrtl(long double);
double		tan(double);
float		tanf(float);
double		tanh(double);
float		tanhf(float);
long double tanhl(long double);
long double tanl(long double);
double		tgamma(double);
float		tgammaf(float);
long double tgammal(long double);
double		trunc(double);
float		truncf(float);
long double truncl(long double);
double		y0(double);
double		y1(double);
double		yn(int, double);

extern int signgam;

__END_DECLS

#endif