reference, declarationdefinition
definition → references, declarations, derived classes, virtual overrides
reference to multiple definitions → definitions
unreferenced
    1
    2
    3
    4
    5
    6
    7
    8
    9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20
   21
   22
   23
   24
   25
   26
   27
   28
   29
   30
   31
   32
   33
   34
   35
   36
   37
   38
   39
   40
   41
   42
   43
   44
   45
   46
   47
   48
   49
   50
   51
   52
   53
   54
   55
   56
   57
   58
   59
   60
   61
   62
   63
   64
   65
   66
   67
   68
   69
   70
   71
   72
   73
   74
   75
   76
   77
   78
   79
   80
   81
   82
   83
   84
   85
   86
   87
   88
   89
   90
   91
   92
   93
   94
   95
   96
   97
   98
   99
  100
  101
  102
  103
  104
  105
  106
  107
  108
  109
  110
  111
  112
  113
  114
  115
  116
  117
  118
  119
  120
  121
  122
  123
  124
  125
  126
  127
  128
  129
  130
  131
  132
  133
  134
  135
  136
  137
  138
  139
  140
  141
  142
  143
  144
  145
  146
  147
  148
  149
  150
  151
  152
  153
  154
  155
  156
  157
  158
  159
  160
  161
  162
  163
  164
  165
  166
  167
  168
  169
  170
  171
  172
  173
  174
/* Copyright (C) 1997-2018 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, see
   <http://www.gnu.org/licenses/>.  */

/*
 * ISO C99 7.6: Floating-point environment	<fenv.h>
 */

#ifndef _FENV_H
#define _FENV_H	1

#define __GLIBC_INTERNAL_STARTING_HEADER_IMPLEMENTATION
#include <bits/libc-header-start.h>

/* Get the architecture dependend definitions.  The following definitions
   are expected to be done:

   fenv_t	type for object representing an entire floating-point
		environment

   FE_DFL_ENV	macro of type pointer to fenv_t to be used as the argument
		to functions taking an argument of type fenv_t; in this
		case the default environment will be used

   fexcept_t	type for object representing the floating-point exception
		flags including status associated with the flags

   femode_t	type for object representing floating-point control modes

   FE_DFL_MODE	macro of type pointer to const femode_t to be used as the
		argument to fesetmode; in this case the default control
		modes will be used

   The following macros are defined iff the implementation supports this
   kind of exception.
   FE_INEXACT		inexact result
   FE_DIVBYZERO		division by zero
   FE_UNDERFLOW		result not representable due to underflow
   FE_OVERFLOW		result not representable due to overflow
   FE_INVALID		invalid operation

   FE_ALL_EXCEPT	bitwise OR of all supported exceptions

   The next macros are defined iff the appropriate rounding mode is
   supported by the implementation.
   FE_TONEAREST		round to nearest
   FE_UPWARD		round toward +Inf
   FE_DOWNWARD		round toward -Inf
   FE_TOWARDZERO	round toward 0
*/
#include <bits/fenv.h>

__BEGIN_DECLS

/* Floating-point exception handling.  */

/* Clear the supported exceptions represented by EXCEPTS.  */
extern int feclearexcept (int __excepts) __THROW;

/* Store implementation-defined representation of the exception flags
   indicated by EXCEPTS in the object pointed to by FLAGP.  */
extern int fegetexceptflag (fexcept_t *__flagp, int __excepts) __THROW;

/* Raise the supported exceptions represented by EXCEPTS.  */
extern int feraiseexcept (int __excepts) __THROW;

#if __GLIBC_USE (IEC_60559_BFP_EXT)
/* Set the supported exception flags represented by EXCEPTS, without
   causing enabled traps to be taken.  */
extern int fesetexcept (int __excepts) __THROW;
#endif

/* Set complete status for exceptions indicated by EXCEPTS according to
   the representation in the object pointed to by FLAGP.  */
extern int fesetexceptflag (const fexcept_t *__flagp, int __excepts) __THROW;

/* Determine which of subset of the exceptions specified by EXCEPTS are
   currently set.  */
extern int fetestexcept (int __excepts) __THROW;

#if __GLIBC_USE (IEC_60559_BFP_EXT)
/* Determine which of subset of the exceptions specified by EXCEPTS
   are set in *FLAGP.  */
extern int fetestexceptflag (const fexcept_t *__flagp, int __excepts) __THROW;
#endif


/* Rounding control.  */

/* Get current rounding direction.  */
extern int fegetround (void) __THROW __attribute_pure__;

/* Establish the rounding direction represented by ROUND.  */
extern int fesetround (int __rounding_direction) __THROW;


/* Floating-point environment.  */

/* Store the current floating-point environment in the object pointed
   to by ENVP.  */
extern int fegetenv (fenv_t *__envp) __THROW;

/* Save the current environment in the object pointed to by ENVP, clear
   exception flags and install a non-stop mode (if available) for all
   exceptions.  */
extern int feholdexcept (fenv_t *__envp) __THROW;

/* Establish the floating-point environment represented by the object
   pointed to by ENVP.  */
extern int fesetenv (const fenv_t *__envp) __THROW;

/* Save current exceptions in temporary storage, install environment
   represented by object pointed to by ENVP and raise exceptions
   according to saved exceptions.  */
extern int feupdateenv (const fenv_t *__envp) __THROW;


/* Control modes.  */

#if __GLIBC_USE (IEC_60559_BFP_EXT)
/* Store the current floating-point control modes in the object
   pointed to by MODEP.  */
extern int fegetmode (femode_t *__modep) __THROW;

/* Establish the floating-point control modes represented by the
   object pointed to by MODEP.  */
extern int fesetmode (const femode_t *__modep) __THROW;
#endif

/* Include optimization.  */
#ifdef __OPTIMIZE__
# include <bits/fenvinline.h>
#endif

/* NaN support.  */

#if (__GLIBC_USE (IEC_60559_BFP_EXT)		\
     && defined FE_INVALID			\
     && defined __SUPPORT_SNAN__)
# define FE_SNANS_ALWAYS_SIGNAL	1
#endif

#ifdef __USE_GNU

/* Enable individual exceptions.  Will not enable more exceptions than
   EXCEPTS specifies.  Returns the previous enabled exceptions if all
   exceptions are successfully set, otherwise returns -1.  */
extern int feenableexcept (int __excepts) __THROW;

/* Disable individual exceptions.  Will not disable more exceptions than
   EXCEPTS specifies.  Returns the previous enabled exceptions if all
   exceptions are successfully disabled, otherwise returns -1.  */
extern int fedisableexcept (int __excepts) __THROW;

/* Return enabled exceptions.  */
extern int fegetexcept (void) __THROW;
#endif

__END_DECLS

#endif /* fenv.h */