xref: /haiku/src/system/libroot/posix/glibc/math/math.h (revision 93aeb8c3bc3f13cb1f282e3e749258a23790d947)
1 /* Declarations for math functions.
2    Copyright (C) 1991-1993,1995-1999,2001,2002 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4 
5    The GNU C Library is free software; you can redistribute it and/or
6    modify it under the terms of the GNU Lesser General Public
7    License as published by the Free Software Foundation; either
8    version 2.1 of the License, or (at your option) any later version.
9 
10    The GNU C Library is distributed in the hope that it will be useful,
11    but WITHOUT ANY WARRANTY; without even the implied warranty of
12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13    Lesser General Public License for more details.
14 
15    You should have received a copy of the GNU Lesser General Public
16    License along with the GNU C Library; if not, write to the Free
17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
18    02111-1307 USA.  */
19 
20 /*
21  *	ISO C99 Standard: 7.12 Mathematics	<math.h>
22  */
23 
24 #ifndef	_MATH_H
25 #define	_MATH_H	1
26 
27 #include <features.h>
28 
29 __BEGIN_DECLS
30 
31 /* Get machine-dependent HUGE_VAL value (returned on overflow).
32    On all IEEE754 machines, this is +Infinity.  */
33 #include <bits/huge_val.h>
34 
35 /* Get machine-dependent NAN value (returned for some domain errors).  */
36 #ifdef	 __USE_ISOC99
37 # include <bits/nan.h>
38 #endif
39 /* Get general and ISO C99 specific information.  */
40 #include <bits/mathdef.h>
41 
42 
43 /* The file <bits/mathcalls.h> contains the prototypes for all the
44    actual math functions.  These macros are used for those prototypes,
45    so we can easily declare each function as both `name' and `__name',
46    and can declare the float versions `namef' and `__namef'.  */
47 
48 #define __MATHCALL(function,suffix, args)	\
49   __MATHDECL (_Mdouble_,function,suffix, args)
50 #define __MATHDECL(type, function,suffix, args) \
51   __MATHDECL_1(type, function,suffix, args); \
52   __MATHDECL_1(type, __CONCAT(__,function),suffix, args)
53 #define __MATHCALLX(function,suffix, args, attrib)	\
54   __MATHDECLX (_Mdouble_,function,suffix, args, attrib)
55 #define __MATHDECLX(type, function,suffix, args, attrib) \
56   __MATHDECL_1(type, function,suffix, args) __attribute__ (attrib); \
57   __MATHDECL_1(type, __CONCAT(__,function),suffix, args) __attribute__ (attrib)
58 #define __MATHDECL_1(type, function,suffix, args) \
59   extern type __MATH_PRECNAME(function,suffix) args __THROW
60 
61 #define _Mdouble_ 		double
62 #define __MATH_PRECNAME(name,r)	__CONCAT(name,r)
63 # define _Mdouble_BEGIN_NAMESPACE __BEGIN_NAMESPACE_STD
64 # define _Mdouble_END_NAMESPACE   __END_NAMESPACE_STD
65 #include <bits/mathcalls.h>
66 #undef	_Mdouble_
67 #undef _Mdouble_BEGIN_NAMESPACE
68 #undef _Mdouble_END_NAMESPACE
69 #undef	__MATH_PRECNAME
70 
71 #if defined __USE_MISC || defined __USE_ISOC99
72 
73 
74 /* Include the file of declarations again, this time using `float'
75    instead of `double' and appending f to each function name.  */
76 
77 # ifndef _Mfloat_
78 #  define _Mfloat_		float
79 # endif
80 # define _Mdouble_ 		_Mfloat_
81 # ifdef __STDC__
82 #  define __MATH_PRECNAME(name,r) name##f##r
83 # else
84 #  define __MATH_PRECNAME(name,r) name/**/f/**/r
85 # endif
86 # define _Mdouble_BEGIN_NAMESPACE __BEGIN_NAMESPACE_C99
87 # define _Mdouble_END_NAMESPACE   __END_NAMESPACE_C99
88 # include <bits/mathcalls.h>
89 # undef	_Mdouble_
90 # undef _Mdouble_BEGIN_NAMESPACE
91 # undef _Mdouble_END_NAMESPACE
92 # undef	__MATH_PRECNAME
93 
94 # if (__STDC__ - 0 || __GNUC__ - 0) && !defined __NO_LONG_DOUBLE_MATH
95 /* Include the file of declarations again, this time using `long double'
96    instead of `double' and appending l to each function name.  */
97 
98 #  ifndef _Mlong_double_
99 #   define _Mlong_double_	long double
100 #  endif
101 #  define _Mdouble_ 		_Mlong_double_
102 #  ifdef __STDC__
103 #   define __MATH_PRECNAME(name,r) name##l##r
104 #  else
105 #   define __MATH_PRECNAME(name,r) name/**/l/**/r
106 #  endif
107 #  define _Mdouble_BEGIN_NAMESPACE __BEGIN_NAMESPACE_C99
108 #  define _Mdouble_END_NAMESPACE   __END_NAMESPACE_C99
109 #  include <bits/mathcalls.h>
110 #  undef _Mdouble_
111 # undef _Mdouble_BEGIN_NAMESPACE
112 # undef _Mdouble_END_NAMESPACE
113 #  undef __MATH_PRECNAME
114 
115 # endif /* __STDC__ || __GNUC__ */
116 
117 #endif	/* Use misc or ISO C99.  */
118 #undef	__MATHDECL_1
119 #undef	__MATHDECL
120 #undef	__MATHCALL
121 
122 
123 #if defined __USE_MISC || defined __USE_XOPEN
124 /* This variable is used by `gamma' and `lgamma'.  */
125 extern int signgam;
126 #endif
127 
128 
129 /* ISO C99 defines some generic macros which work on any data type.  */
130 #if __USE_ISOC99
131 
132 /* Get the architecture specific values describing the floating-point
133    evaluation.  The following symbols will get defined:
134 
135     float_t	floating-point type at least as wide as `float' used
136 		to evaluate `float' expressions
137     double_t	floating-point type at least as wide as `double' used
138 		to evaluate `double' expressions
139 
140     FLT_EVAL_METHOD
141 		Defined to
142 		  0	if `float_t' is `float' and `double_t' is `double'
143 		  1	if `float_t' and `double_t' are `double'
144 		  2	if `float_t' and `double_t' are `long double'
145 		  else	`float_t' and `double_t' are unspecified
146 
147     INFINITY	representation of the infinity value of type `float'
148 
149     FP_FAST_FMA
150     FP_FAST_FMAF
151     FP_FAST_FMAL
152 		If defined it indicates that the `fma' function
153 		generally executes about as fast as a multiply and an add.
154 		This macro is defined only iff the `fma' function is
155 		implemented directly with a hardware multiply-add instructions.
156 
157     FP_ILOGB0	Expands to a value returned by `ilogb (0.0)'.
158     FP_ILOGBNAN	Expands to a value returned by `ilogb (NAN)'.
159 
160     DECIMAL_DIG	Number of decimal digits supported by conversion between
161 		decimal and all internal floating-point formats.
162 
163 */
164 
165 /* All floating-point numbers can be put in one of these categories.  */
166 enum
167   {
168     FP_NAN,
169 # define FP_NAN FP_NAN
170     FP_INFINITE,
171 # define FP_INFINITE FP_INFINITE
172     FP_ZERO,
173 # define FP_ZERO FP_ZERO
174     FP_SUBNORMAL,
175 # define FP_SUBNORMAL FP_SUBNORMAL
176     FP_NORMAL
177 # define FP_NORMAL FP_NORMAL
178   };
179 
180 /* Return number of classification appropriate for X.  */
181 # ifdef __NO_LONG_DOUBLE_MATH
182 #  define fpclassify(x) \
183      (sizeof (x) == sizeof (float) ? __fpclassifyf (x) : __fpclassify (x))
184 # else
185 #  define fpclassify(x) \
186      (sizeof (x) == sizeof (float)					      \
187       ? __fpclassifyf (x)						      \
188       : sizeof (x) == sizeof (double)					      \
189       ? __fpclassify (x) : __fpclassifyl (x))
190 # endif
191 
192 /* Return nonzero value if sign of X is negative.  */
193 # ifdef __NO_LONG_DOUBLE_MATH
194 #  define signbit(x) \
195      (sizeof (x) == sizeof (float) ? __signbitf (x) : __signbit (x))
196 # else
197 #  define signbit(x) \
198      (sizeof (x) == sizeof (float)					      \
199       ? __signbitf (x)							      \
200       : sizeof (x) == sizeof (double)					      \
201       ? __signbit (x) : __signbitl (x))
202 # endif
203 
204 /* Return nonzero value if X is not +-Inf or NaN.  */
205 # ifdef __NO_LONG_DOUBLE_MATH
206 #  define isfinite(x) \
207      (sizeof (x) == sizeof (float) ? __finitef (x) : __finite (x))
208 # else
209 #  define isfinite(x) \
210      (sizeof (x) == sizeof (float)					      \
211       ? __finitef (x)							      \
212       : sizeof (x) == sizeof (double)					      \
213       ? __finite (x) : __finitel (x))
214 # endif
215 
216 /* Return nonzero value if X is neither zero, subnormal, Inf, nor NaN.  */
217 # define isnormal(x) (fpclassify (x) == FP_NORMAL)
218 
219 /* Return nonzero value if X is a NaN.  We could use `fpclassify' but
220    we already have this functions `__isnan' and it is faster.  */
221 # ifdef __NO_LONG_DOUBLE_MATH
222 #  define isnan(x) \
223      (sizeof (x) == sizeof (float) ? __isnanf (x) : __isnan (x))
224 # else
225 #  define isnan(x) \
226      (sizeof (x) == sizeof (float)					      \
227       ? __isnanf (x)							      \
228       : sizeof (x) == sizeof (double)					      \
229       ? __isnan (x) : __isnanl (x))
230 # endif
231 
232 /* Return nonzero value is X is positive or negative infinity.  */
233 # ifdef __NO_LONG_DOUBLE_MATH
234 #  define isinf(x) \
235      (sizeof (x) == sizeof (float) ? __isinff (x) : __isinf (x))
236 # else
237 #  define isinf(x) \
238      (sizeof (x) == sizeof (float)					      \
239       ? __isinff (x)							      \
240       : sizeof (x) == sizeof (double)					      \
241       ? __isinf (x) : __isinfl (x))
242 # endif
243 
244 /* Bitmasks for the math_errhandling macro.  */
245 # define MATH_ERRNO	1	/* errno set by math functions.  */
246 # define MATH_ERREXCEPT	2	/* Exceptions raised by math functions.  */
247 
248 #endif /* Use ISO C99.  */
249 
250 #ifdef	__USE_MISC
251 /* Support for various different standard error handling behaviors.  */
252 typedef enum
253 {
254   _IEEE_ = -1,	/* According to IEEE 754/IEEE 854.  */
255   _SVID_,	/* According to System V, release 4.  */
256   _XOPEN_,	/* Nowadays also Unix98.  */
257   _POSIX_,
258   _ISOC_	/* Actually this is ISO C99.  */
259 } _LIB_VERSION_TYPE;
260 
261 /* This variable can be changed at run-time to any of the values above to
262    affect floating point error handling behavior (it may also be necessary
263    to change the hardware FPU exception settings).  */
264 extern _LIB_VERSION_TYPE _LIB_VERSION;
265 #endif
266 
267 
268 #ifdef __USE_SVID
269 /* In SVID error handling, `matherr' is called with this description
270    of the exceptional condition.
271 
272    We have a problem when using C++ since `exception' is a reserved
273    name in C++.  */
274 # ifdef __cplusplus
275 struct __exception
276 # else
277 struct exception
278 # endif
279   {
280     int type;
281     char *name;
282     double arg1;
283     double arg2;
284     double retval;
285   };
286 
287 # ifdef __cplusplus
288 extern int matherr (struct __exception *__exc) throw ();
289 # else
290 extern int matherr (struct exception *__exc);
291 # endif
292 
293 # define X_TLOSS	1.41484755040568800000e+16
294 
295 /* Types of exceptions in the `type' field.  */
296 # define DOMAIN		1
297 # define SING		2
298 # define OVERFLOW	3
299 # define UNDERFLOW	4
300 # define TLOSS		5
301 # define PLOSS		6
302 
303 /* SVID mode specifies returning this large value instead of infinity.  */
304 # define HUGE		3.40282347e+38F
305 
306 #else	/* !SVID */
307 
308 # ifdef __USE_XOPEN
309 /* X/Open wants another strange constant.  */
310 #  define MAXFLOAT	3.40282347e+38F
311 # endif
312 
313 #endif	/* SVID */
314 
315 
316 /* Some useful constants.  */
317 #if defined __USE_BSD || defined __USE_XOPEN
318 # define M_E		2.7182818284590452354	/* e */
319 # define M_LOG2E	1.4426950408889634074	/* log_2 e */
320 # define M_LOG10E	0.43429448190325182765	/* log_10 e */
321 # define M_LN2		0.69314718055994530942	/* log_e 2 */
322 # define M_LN10		2.30258509299404568402	/* log_e 10 */
323 # define M_PI		3.14159265358979323846	/* pi */
324 # define M_PI_2		1.57079632679489661923	/* pi/2 */
325 # define M_PI_4		0.78539816339744830962	/* pi/4 */
326 # define M_1_PI		0.31830988618379067154	/* 1/pi */
327 # define M_2_PI		0.63661977236758134308	/* 2/pi */
328 # define M_2_SQRTPI	1.12837916709551257390	/* 2/sqrt(pi) */
329 # define M_SQRT2	1.41421356237309504880	/* sqrt(2) */
330 # define M_SQRT1_2	0.70710678118654752440	/* 1/sqrt(2) */
331 #endif
332 
333 /* The above constants are not adequate for computation using `long double's.
334    Therefore we provide as an extension constants with similar names as a
335    GNU extension.  Provide enough digits for the 128-bit IEEE quad.  */
336 #ifdef __USE_GNU
337 # define M_El		2.7182818284590452353602874713526625L  /* e */
338 # define M_LOG2El	1.4426950408889634073599246810018921L  /* log_2 e */
339 # define M_LOG10El	0.4342944819032518276511289189166051L  /* log_10 e */
340 # define M_LN2l		0.6931471805599453094172321214581766L  /* log_e 2 */
341 # define M_LN10l	2.3025850929940456840179914546843642L  /* log_e 10 */
342 # define M_PIl		3.1415926535897932384626433832795029L  /* pi */
343 # define M_PI_2l	1.5707963267948966192313216916397514L  /* pi/2 */
344 # define M_PI_4l	0.7853981633974483096156608458198757L  /* pi/4 */
345 # define M_1_PIl	0.3183098861837906715377675267450287L  /* 1/pi */
346 # define M_2_PIl	0.6366197723675813430755350534900574L  /* 2/pi */
347 # define M_2_SQRTPIl	1.1283791670955125738961589031215452L  /* 2/sqrt(pi) */
348 # define M_SQRT2l	1.4142135623730950488016887242096981L  /* sqrt(2) */
349 # define M_SQRT1_2l	0.7071067811865475244008443621048490L  /* 1/sqrt(2) */
350 #endif
351 
352 
353 /* When compiling in strict ISO C compatible mode we must not use the
354    inline functions since they, among other things, do not set the
355    `errno' variable correctly.  */
356 #if defined __STRICT_ANSI__ && !defined __NO_MATH_INLINES
357 # define __NO_MATH_INLINES	1
358 #endif
359 
360 /* Get machine-dependent inline versions (if there are any).  */
361 #ifdef __USE_EXTERN_INLINES
362 # include <bits/mathinline.h>
363 #endif
364 
365 
366 #if __USE_ISOC99
367 /* ISO C99 defines some macros to compare number while taking care
368    for unordered numbers.  Since many FPUs provide special
369    instructions to support these operations and these tests are
370    defined in <bits/mathinline.h>, we define the generic macros at
371    this late point and only if they are not defined yet.  */
372 
373 /* Return nonzero value if X is greater than Y.  */
374 # ifndef isgreater
375 #  define isgreater(x, y) \
376   (__extension__							      \
377    ({ __typeof__(x) __x = (x); __typeof__(y) __y = (y);			      \
378       !isunordered (__x, __y) && __x > __y; }))
379 # endif
380 
381 /* Return nonzero value if X is greater than or equal to Y.  */
382 # ifndef isgreaterequal
383 #  define isgreaterequal(x, y) \
384   (__extension__							      \
385    ({ __typeof__(x) __x = (x); __typeof__(y) __y = (y);			      \
386       !isunordered (__x, __y) && __x >= __y; }))
387 # endif
388 
389 /* Return nonzero value if X is less than Y.  */
390 # ifndef isless
391 #  define isless(x, y) \
392   (__extension__							      \
393    ({ __typeof__(x) __x = (x); __typeof__(y) __y = (y);			      \
394       !isunordered (__x, __y) && __x < __y; }))
395 # endif
396 
397 /* Return nonzero value if X is less than or equal to Y.  */
398 # ifndef islessequal
399 #  define islessequal(x, y) \
400   (__extension__							      \
401    ({ __typeof__(x) __x = (x); __typeof__(y) __y = (y);			      \
402       !isunordered (__x, __y) && __x <= __y; }))
403 # endif
404 
405 /* Return nonzero value if either X is less than Y or Y is less than X.  */
406 # ifndef islessgreater
407 #  define islessgreater(x, y) \
408   (__extension__							      \
409    ({ __typeof__(x) __x = (x); __typeof__(y) __y = (y);			      \
410       !isunordered (__x, __y) && (__x < __y || __y < __x); }))
411 # endif
412 
413 /* Return nonzero value if arguments are unordered.  */
414 # ifndef isunordered
415 #  define isunordered(u, v) \
416   (__extension__							      \
417    ({ __typeof__(u) __u = (u); __typeof__(v) __v = (v);			      \
418       fpclassify (__u) == FP_NAN || fpclassify (__v) == FP_NAN; }))
419 # endif
420 
421 #endif
422 
423 __END_DECLS
424 
425 
426 #endif /* math.h  */
427