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/*
	WARNING: This file was generated by dkct.
	Changes you make here will be lost if dkct is run again!
	You should modify the original source and run dkct on it.
	Original source: dk3mafpe.ctr
*/

/*
Copyright (C) 2014-2017, Dirk Krause

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

* Redistributions of source code must retain the above copyright notice,
  this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above opyright notice,
  this list of conditions and the following disclaimer in the documentation
  and/or other materials provided with the distribution.
* Neither the name of the author nor the names of contributors may be used
  to endorse or promote products derived from this software without specific
  prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS''
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED.
IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY
DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#ifndef DK3MAFPE_H_INCLUDED
/** Avoid multiple inclusions. */
#define DK3MAFPE_H_INCLUDED 1


#line 9 "dk3mafpe.ctr"

/**	@file	dk3mafpe.h	Floating point exception handling.

Before doing any floating point calculation, use dk3mafpe_get_handling_type()
to check whether an exception handling mechanism is available.

The function returns DK3_MA_FPE_HANDLING_CLEARFP on Windows systems
if _clearfp() and _statusfp() are available. It returns
DK3_MA_FPE_HANDLING_FETESTEXCEPT if the POSIX floating point exception
functions fetestexcept() and feclearexcept() are available.

If none of these mechanisms is available, DK3_MA_FPE_HANDLING_NONE is
returned. Your program should issue a warning.

Before doing a floating point calculation use dk3mafpe_clear() to
clear the FPU status word.

After doing a floating point calculation use dk3mafpe_get() or
dk3mafpe_get_and_clear() to retrieve the status word.
Check the status word against DK3MAFPE_ALL (and-combine them) to see
if any exception occured.

If your calculation results in just one double you can use
dk3mafpe_isfinite() and/or dk3mafpe_isnormal() to check the value.
If the dk3mafpe_isfinite() test fails, the value is of no use.
If the dk3mafpe_isnormal() test fails, the result is very small, it uses
denormalized representation and has probably and likely lost
much of it's precision.
*/

#include <dk3conf.h>

#if DK3_HAVE_FLOAT_H
#include <float.h>
#endif
#if DK3_HAVE_FENV_H
#include <fenv.h>
#endif



#if DK3_ON_WINDOWS
/**	Floating point exceptions set.
*/
typedef unsigned int	dk3_ma_fpe_t;

#if DK3_HAVE__CLEARFP

/**	Division by 0.
*/
#define	DK3MAFPE_DIVBYZERO	(_SW_ZERODIVIDE)

/**	Inexact result (either overflow or underflow).
*/
#define	DK3MAFPE_INEXACT	(_SW_INEXACT)

/**	Not a number (0/0 or infty - infty).
*/
#define	DK3MAFPE_INVALID	(_SW_INVALID)

/**	Result too large for representation.
*/
#define	DK3MAFPE_OVERFLOW	(_SW_OVERFLOW)

/**	Result too small for normalized representation.
*/
#define	DK3MAFPE_UNDERFLOW	(_SW_UNDERFLOW)

/**	Denormalized number.
*/
#define	DK3MAFPE_DENORMAL	(_SW_DENORMAL)

/**	Or-combination of all supported exceptions.
*/
#define	DK3MAFPE_ALL \
	((_SW_ZERODIVIDE) \
	| (_SW_INEXACT) \
	| (_SW_INVALID) \
	| (_SW_OVERFLOW) \
	| (_SW_UNDERFLOW) \
	| (_SW_DENORMAL))

#else

/**	Division by 0.
*/
#define	DK3MAFPE_DIVBYZERO	0

/**	Inexact result (either overflow or underflow).
*/
#define	DK3MAFPE_INEXACT	0

/**	Not a number (0/0 or infty - infty).
*/
#define	DK3MAFPE_INVALID	0

/**	Result too large for representation.
*/
#define	DK3MAFPE_OVERFLOW	0

/**	Result too small for normalized representation.
*/
#define	DK3MAFPE_UNDERFLOW	0

/**	Denormalized number.
*/
#define	DK3MAFPE_DENORMAL	0

/**	Or-combination of all supported exceptions.
*/
#define	DK3MAFPE_ALL		0

#endif
#else
/**	Floating point exceptions set.
*/
typedef int		dk3_ma_fpe_t;

#if DK3_HAVE_FETESTEXCEPT

/**	Division by 0.
*/
#define	DK3MAFPE_DIVBYZERO	(FE_DIVBYZERO)

/**	Inexact result (either overflow or underflow).
*/
#define	DK3MAFPE_INEXACT	(FE_INEXACT)

/**	Not a number (0/0 or infty - infty).
*/
#define	DK3MAFPE_INVALID	(FE_INVALID)

/**	Result too large for representation.
*/
#define	DK3MAFPE_OVERFLOW	(FE_OVERFLOW)

/**	Result too small for normalized representation.
*/
#define	DK3MAFPE_UNDERFLOW	(FE_UNDERFLOW)

/**	Denormalized number.
*/
#define	DK3MAFPE_DENORMAL	0

/**	Or-combination of all supported exceptions.
*/
#define	DK3MAFPE_ALL		(FE_ALL_EXCEPT)

#else

/**	Division by 0.
*/
#define	DK3MAFPE_DIVBYZERO	0

/**	Inexact result (either overflow or underflow).
*/
#define	DK3MAFPE_INEXACT	0

/**	Not a number (0/0 or infty - infty).
*/
#define	DK3MAFPE_INVALID	0

/**	Result too large for representation.
*/
#define	DK3MAFPE_OVERFLOW	0

/**	Result too small for normalized representation.
*/
#define	DK3MAFPE_UNDERFLOW	0

/**	Denormalized number.
*/
#define	DK3MAFPE_DENORMAL	0

/**	Or-combination of all supported exceptions.
*/
#define	DK3MAFPE_ALL		0

#endif
#endif



/**	Different handling types for floating point exceptions.
*/
enum {

  /**	No fpe exception handling available.
  */
  DK3_MA_FPE_HANDLING_NONE	=	0,

  /**	POSIX exception handling using fetestexcept() and friends.
  */
  DK3_MA_FPE_HANDLING_FETESTEXCEPT,

  /**	Windows exception handling using _clearfp() and friends.
  */
  DK3_MA_FPE_HANDLING_CLEARFP

};



#ifdef __cplusplus
extern "C" {
#endif

/**	Retrieve exception set.
	@return	Exceptions found.
*/
dk3_ma_fpe_t
dk3mafpe_get(void);

/**	Clear exception set.
*/
void
dk3mafpe_clear(void);

/**	Retrieve exception set and clear.
	@return	Exceptions found.
*/
dk3_ma_fpe_t
dk3mafpe_get_and_clear(void);

/**	Get exception handling type.
	@return	One from DK3_MA_FPE_HANDLING_NONE,
	DK3_MA_FPE_HANDLING_FETESTEXCEPT, DK3_MA_FPE_HANDLING_CLEARFP.
*/
int
dk3mafpe_get_handling_type(void);

/**	Check whether a number is normalized.
	@param	x	Number to check.
	@return	Non-null result on success, 0 on error.
*/
int
dk3mafpe_isnormal(double x);

/**	Check whether a number is finite (not NAN, not INF).
	@param	x	Number to check.
	@return	Non-null result on success, 0 on error.
*/
int
dk3mafpe_isfinite(double x);

#ifdef __cplusplus
}
#endif



#endif