Use read_int in vfscanf
[glibc.git] / math / math.h
blob7c0c7095239f728577852d68a48f44844531d368
1 /* Declarations for math functions.
2 Copyright (C) 1991-2016 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
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.
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.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <http://www.gnu.org/licenses/>. */
20 * ISO C99 Standard: 7.12 Mathematics <math.h>
23 #ifndef _MATH_H
24 #define _MATH_H 1
26 #define __GLIBC_INTERNAL_STARTING_HEADER_IMPLEMENTATION
27 #include <bits/libc-header-start.h>
29 __BEGIN_DECLS
31 /* Get machine-dependent vector math functions declarations. */
32 #include <bits/math-vector.h>
34 /* Get machine-dependent HUGE_VAL value (returned on overflow).
35 On all IEEE754 machines, this is +Infinity. */
36 #include <bits/huge_val.h>
37 #ifdef __USE_ISOC99
38 # include <bits/huge_valf.h>
39 # include <bits/huge_vall.h>
41 /* Get machine-dependent INFINITY value. */
42 # include <bits/inf.h>
44 /* Get machine-dependent NAN value (returned for some domain errors). */
45 # include <bits/nan.h>
46 #endif /* __USE_ISOC99 */
48 /* Get the architecture specific values describing the floating-point
49 evaluation. The following symbols will get defined:
51 float_t floating-point type at least as wide as `float' used
52 to evaluate `float' expressions
53 double_t floating-point type at least as wide as `double' used
54 to evaluate `double' expressions
56 FP_FAST_FMA
57 FP_FAST_FMAF
58 FP_FAST_FMAL
59 If defined it indicates that the `fma' function
60 generally executes about as fast as a multiply and an add.
61 This macro is defined only iff the `fma' function is
62 implemented directly with a hardware multiply-add instructions.
64 FP_ILOGB0 Expands to a value returned by `ilogb (0.0)'.
65 FP_ILOGBNAN Expands to a value returned by `ilogb (NAN)'.
69 #include <bits/mathdef.h>
71 /* The file <bits/mathcalls.h> contains the prototypes for all the
72 actual math functions. These macros are used for those prototypes,
73 so we can easily declare each function as both `name' and `__name',
74 and can declare the float versions `namef' and `__namef'. */
76 #define __SIMD_DECL(function) __CONCAT (__DECL_SIMD_, function)
78 #define __MATHCALL_VEC(function, suffix, args) \
79 __SIMD_DECL (__MATH_PRECNAME (function, suffix)) \
80 __MATHCALL (function, suffix, args)
82 #define __MATHDECL_VEC(type, function,suffix, args) \
83 __SIMD_DECL (__MATH_PRECNAME (function, suffix)) \
84 __MATHDECL(type, function,suffix, args)
86 #define __MATHCALL(function,suffix, args) \
87 __MATHDECL (_Mdouble_,function,suffix, args)
88 #define __MATHDECL(type, function,suffix, args) \
89 __MATHDECL_1(type, function,suffix, args); \
90 __MATHDECL_1(type, __CONCAT(__,function),suffix, args)
91 #define __MATHCALLX(function,suffix, args, attrib) \
92 __MATHDECLX (_Mdouble_,function,suffix, args, attrib)
93 #define __MATHDECLX(type, function,suffix, args, attrib) \
94 __MATHDECL_1(type, function,suffix, args) __attribute__ (attrib); \
95 __MATHDECL_1(type, __CONCAT(__,function),suffix, args) __attribute__ (attrib)
96 #define __MATHDECL_1(type, function,suffix, args) \
97 extern type __MATH_PRECNAME(function,suffix) args __THROW
99 #define _Mdouble_ double
100 #define __MATH_PRECNAME(name,r) __CONCAT(name,r)
101 #define __MATH_DECLARING_DOUBLE 1
102 #define _Mdouble_BEGIN_NAMESPACE __BEGIN_NAMESPACE_STD
103 #define _Mdouble_END_NAMESPACE __END_NAMESPACE_STD
104 #include <bits/mathcalls.h>
105 #undef _Mdouble_
106 #undef _Mdouble_BEGIN_NAMESPACE
107 #undef _Mdouble_END_NAMESPACE
108 #undef __MATH_PRECNAME
109 #undef __MATH_DECLARING_DOUBLE
111 #ifdef __USE_ISOC99
114 /* Include the file of declarations again, this time using `float'
115 instead of `double' and appending f to each function name. */
117 # ifndef _Mfloat_
118 # define _Mfloat_ float
119 # endif
120 # define _Mdouble_ _Mfloat_
121 # define __MATH_PRECNAME(name,r) name##f##r
122 # define __MATH_DECLARING_DOUBLE 0
123 # define _Mdouble_BEGIN_NAMESPACE __BEGIN_NAMESPACE_C99
124 # define _Mdouble_END_NAMESPACE __END_NAMESPACE_C99
125 # include <bits/mathcalls.h>
126 # undef _Mdouble_
127 # undef _Mdouble_BEGIN_NAMESPACE
128 # undef _Mdouble_END_NAMESPACE
129 # undef __MATH_PRECNAME
130 # undef __MATH_DECLARING_DOUBLE
132 # if !(defined __NO_LONG_DOUBLE_MATH && defined _LIBC) \
133 || defined __LDBL_COMPAT \
134 || defined _LIBC_TEST
135 # ifdef __LDBL_COMPAT
137 # ifdef __USE_ISOC99
138 extern float __nldbl_nexttowardf (float __x, long double __y)
139 __THROW __attribute__ ((__const__));
140 # ifdef __REDIRECT_NTH
141 extern float __REDIRECT_NTH (nexttowardf, (float __x, long double __y),
142 __nldbl_nexttowardf)
143 __attribute__ ((__const__));
144 extern double __REDIRECT_NTH (nexttoward, (double __x, long double __y),
145 nextafter) __attribute__ ((__const__));
146 extern long double __REDIRECT_NTH (nexttowardl,
147 (long double __x, long double __y),
148 nextafter) __attribute__ ((__const__));
149 # endif
150 # endif
152 # undef __MATHDECL_1
153 # define __MATHDECL_2(type, function,suffix, args, alias) \
154 extern type __REDIRECT_NTH(__MATH_PRECNAME(function,suffix), \
155 args, alias)
156 # define __MATHDECL_1(type, function,suffix, args) \
157 __MATHDECL_2(type, function,suffix, args, __CONCAT(function,suffix))
158 # endif
160 /* Include the file of declarations again, this time using `long double'
161 instead of `double' and appending l to each function name. */
163 # ifndef _Mlong_double_
164 # define _Mlong_double_ long double
165 # endif
166 # define _Mdouble_ _Mlong_double_
167 # define __MATH_PRECNAME(name,r) name##l##r
168 # define __MATH_DECLARING_DOUBLE 0
169 # define _Mdouble_BEGIN_NAMESPACE __BEGIN_NAMESPACE_C99
170 # define _Mdouble_END_NAMESPACE __END_NAMESPACE_C99
171 # define __MATH_DECLARE_LDOUBLE 1
172 # include <bits/mathcalls.h>
173 # undef _Mdouble_
174 # undef _Mdouble_BEGIN_NAMESPACE
175 # undef _Mdouble_END_NAMESPACE
176 # undef __MATH_PRECNAME
177 # undef __MATH_DECLARING_DOUBLE
179 # endif /* !(__NO_LONG_DOUBLE_MATH && _LIBC) || __LDBL_COMPAT */
181 #endif /* Use ISO C99. */
182 #undef __MATHDECL_1
183 #undef __MATHDECL
184 #undef __MATHCALL
187 #if defined __USE_MISC || defined __USE_XOPEN
188 /* This variable is used by `gamma' and `lgamma'. */
189 extern int signgam;
190 #endif
193 /* ISO C99 defines some generic macros which work on any data type. */
194 #ifdef __USE_ISOC99
196 /* All floating-point numbers can be put in one of these categories. */
197 enum
199 FP_NAN =
200 # define FP_NAN 0
201 FP_NAN,
202 FP_INFINITE =
203 # define FP_INFINITE 1
204 FP_INFINITE,
205 FP_ZERO =
206 # define FP_ZERO 2
207 FP_ZERO,
208 FP_SUBNORMAL =
209 # define FP_SUBNORMAL 3
210 FP_SUBNORMAL,
211 FP_NORMAL =
212 # define FP_NORMAL 4
213 FP_NORMAL
216 /* GCC bug 66462 means we cannot use the math builtins with -fsignaling-nan,
217 so disable builtins if this is enabled. When fixed in a newer GCC,
218 the __SUPPORT_SNAN__ check may be skipped for those versions. */
220 /* Return number of classification appropriate for X. */
221 # if __GNUC_PREREQ (4,4) && !defined __SUPPORT_SNAN__ \
222 && !defined __OPTIMIZE_SIZE__
223 # define fpclassify(x) __builtin_fpclassify (FP_NAN, FP_INFINITE, \
224 FP_NORMAL, FP_SUBNORMAL, FP_ZERO, x)
225 # elif defined __NO_LONG_DOUBLE_MATH
226 # define fpclassify(x) \
227 (sizeof (x) == sizeof (float) ? __fpclassifyf (x) : __fpclassify (x))
228 # else
229 # define fpclassify(x) \
230 (sizeof (x) == sizeof (float) \
231 ? __fpclassifyf (x) \
232 : sizeof (x) == sizeof (double) \
233 ? __fpclassify (x) : __fpclassifyl (x))
234 # endif
236 /* Return nonzero value if sign of X is negative. */
237 # if __GNUC_PREREQ (4,0)
238 # define signbit(x) \
239 (sizeof (x) == sizeof (float) \
240 ? __builtin_signbitf (x) \
241 : sizeof (x) == sizeof (double) \
242 ? __builtin_signbit (x) : __builtin_signbitl (x))
243 # else
244 # ifdef __NO_LONG_DOUBLE_MATH
245 # define signbit(x) \
246 (sizeof (x) == sizeof (float) ? __signbitf (x) : __signbit (x))
247 # else
248 # define signbit(x) \
249 (sizeof (x) == sizeof (float) \
250 ? __signbitf (x) \
251 : sizeof (x) == sizeof (double) \
252 ? __signbit (x) : __signbitl (x))
253 # endif
254 # endif
256 /* Return nonzero value if X is not +-Inf or NaN. */
257 # if __GNUC_PREREQ (4,4) && !defined __SUPPORT_SNAN__
258 # define isfinite(x) __builtin_isfinite (x)
259 # elif defined __NO_LONG_DOUBLE_MATH
260 # define isfinite(x) \
261 (sizeof (x) == sizeof (float) ? __finitef (x) : __finite (x))
262 # else
263 # define isfinite(x) \
264 (sizeof (x) == sizeof (float) \
265 ? __finitef (x) \
266 : sizeof (x) == sizeof (double) \
267 ? __finite (x) : __finitel (x))
268 # endif
270 /* Return nonzero value if X is neither zero, subnormal, Inf, nor NaN. */
271 # if __GNUC_PREREQ (4,4) && !defined __SUPPORT_SNAN__
272 # define isnormal(x) __builtin_isnormal (x)
273 # else
274 # define isnormal(x) (fpclassify (x) == FP_NORMAL)
275 # endif
277 /* Return nonzero value if X is a NaN. We could use `fpclassify' but
278 we already have this functions `__isnan' and it is faster. */
279 # if __GNUC_PREREQ (4,4) && !defined __SUPPORT_SNAN__
280 # define isnan(x) __builtin_isnan (x)
281 # elif defined __NO_LONG_DOUBLE_MATH
282 # define isnan(x) \
283 (sizeof (x) == sizeof (float) ? __isnanf (x) : __isnan (x))
284 # else
285 # define isnan(x) \
286 (sizeof (x) == sizeof (float) \
287 ? __isnanf (x) \
288 : sizeof (x) == sizeof (double) \
289 ? __isnan (x) : __isnanl (x))
290 # endif
292 /* Return nonzero value if X is positive or negative infinity. */
293 # if __GNUC_PREREQ (4,4) && !defined __SUPPORT_SNAN__
294 # define isinf(x) __builtin_isinf_sign (x)
295 # elif defined __NO_LONG_DOUBLE_MATH
296 # define isinf(x) \
297 (sizeof (x) == sizeof (float) ? __isinff (x) : __isinf (x))
298 # else
299 # define isinf(x) \
300 (sizeof (x) == sizeof (float) \
301 ? __isinff (x) \
302 : sizeof (x) == sizeof (double) \
303 ? __isinf (x) : __isinfl (x))
304 # endif
306 /* Bitmasks for the math_errhandling macro. */
307 # define MATH_ERRNO 1 /* errno set by math functions. */
308 # define MATH_ERREXCEPT 2 /* Exceptions raised by math functions. */
310 /* By default all functions support both errno and exception handling.
311 In gcc's fast math mode and if inline functions are defined this
312 might not be true. */
313 # ifndef __FAST_MATH__
314 # define math_errhandling (MATH_ERRNO | MATH_ERREXCEPT)
315 # endif
317 #endif /* Use ISO C99. */
319 #if __GLIBC_USE (IEC_60559_BFP_EXT)
320 # include <bits/iscanonical.h>
322 /* Return nonzero value if X is a signaling NaN. */
323 # ifdef __NO_LONG_DOUBLE_MATH
324 # define issignaling(x) \
325 (sizeof (x) == sizeof (float) ? __issignalingf (x) : __issignaling (x))
326 # else
327 # define issignaling(x) \
328 (sizeof (x) == sizeof (float) \
329 ? __issignalingf (x) \
330 : sizeof (x) == sizeof (double) \
331 ? __issignaling (x) : __issignalingl (x))
332 # endif
334 /* Return nonzero value if X is subnormal. */
335 # define issubnormal(x) (fpclassify (x) == FP_SUBNORMAL)
337 /* Return nonzero value if X is zero. */
338 # ifndef __cplusplus
339 # ifdef __SUPPORT_SNAN__
340 # define iszero(x) (fpclassify (x) == FP_ZERO)
341 # else
342 # define iszero(x) (((__typeof (x)) (x)) == 0)
343 # endif
344 # else /* __cplusplus */
345 extern "C++" {
346 template <class __T> inline bool
347 iszero (__T __val)
349 # ifdef __SUPPORT_SNAN__
350 return fpclassify (__val) == FP_ZERO;
351 # else
352 return __val == 0;
353 # endif
355 } /* extern C++ */
356 # endif /* __cplusplus */
357 #endif /* Use IEC_60559_BFP_EXT. */
359 #ifdef __USE_MISC
360 /* Support for various different standard error handling behaviors. */
361 typedef enum
363 _IEEE_ = -1, /* According to IEEE 754/IEEE 854. */
364 _SVID_, /* According to System V, release 4. */
365 _XOPEN_, /* Nowadays also Unix98. */
366 _POSIX_,
367 _ISOC_ /* Actually this is ISO C99. */
368 } _LIB_VERSION_TYPE;
370 /* This variable can be changed at run-time to any of the values above to
371 affect floating point error handling behavior (it may also be necessary
372 to change the hardware FPU exception settings). */
373 extern _LIB_VERSION_TYPE _LIB_VERSION;
374 #endif
377 #ifdef __USE_MISC
378 /* In SVID error handling, `matherr' is called with this description
379 of the exceptional condition.
381 We have a problem when using C++ since `exception' is a reserved
382 name in C++. */
383 # ifdef __cplusplus
384 struct __exception
385 # else
386 struct exception
387 # endif
389 int type;
390 char *name;
391 double arg1;
392 double arg2;
393 double retval;
396 # ifdef __cplusplus
397 extern int matherr (struct __exception *__exc) throw ();
398 # else
399 extern int matherr (struct exception *__exc);
400 # endif
402 # define X_TLOSS 1.41484755040568800000e+16
404 /* Types of exceptions in the `type' field. */
405 # define DOMAIN 1
406 # define SING 2
407 # define OVERFLOW 3
408 # define UNDERFLOW 4
409 # define TLOSS 5
410 # define PLOSS 6
412 /* SVID mode specifies returning this large value instead of infinity. */
413 # define HUGE 3.40282347e+38F
415 #else /* !Misc. */
417 # ifdef __USE_XOPEN
418 /* X/Open wants another strange constant. */
419 # define MAXFLOAT 3.40282347e+38F
420 # endif
422 #endif /* Misc. */
425 /* Some useful constants. */
426 #if defined __USE_MISC || defined __USE_XOPEN
427 # define M_E 2.7182818284590452354 /* e */
428 # define M_LOG2E 1.4426950408889634074 /* log_2 e */
429 # define M_LOG10E 0.43429448190325182765 /* log_10 e */
430 # define M_LN2 0.69314718055994530942 /* log_e 2 */
431 # define M_LN10 2.30258509299404568402 /* log_e 10 */
432 # define M_PI 3.14159265358979323846 /* pi */
433 # define M_PI_2 1.57079632679489661923 /* pi/2 */
434 # define M_PI_4 0.78539816339744830962 /* pi/4 */
435 # define M_1_PI 0.31830988618379067154 /* 1/pi */
436 # define M_2_PI 0.63661977236758134308 /* 2/pi */
437 # define M_2_SQRTPI 1.12837916709551257390 /* 2/sqrt(pi) */
438 # define M_SQRT2 1.41421356237309504880 /* sqrt(2) */
439 # define M_SQRT1_2 0.70710678118654752440 /* 1/sqrt(2) */
440 #endif
442 /* The above constants are not adequate for computation using `long double's.
443 Therefore we provide as an extension constants with similar names as a
444 GNU extension. Provide enough digits for the 128-bit IEEE quad. */
445 #ifdef __USE_GNU
446 # define M_El 2.718281828459045235360287471352662498L /* e */
447 # define M_LOG2El 1.442695040888963407359924681001892137L /* log_2 e */
448 # define M_LOG10El 0.434294481903251827651128918916605082L /* log_10 e */
449 # define M_LN2l 0.693147180559945309417232121458176568L /* log_e 2 */
450 # define M_LN10l 2.302585092994045684017991454684364208L /* log_e 10 */
451 # define M_PIl 3.141592653589793238462643383279502884L /* pi */
452 # define M_PI_2l 1.570796326794896619231321691639751442L /* pi/2 */
453 # define M_PI_4l 0.785398163397448309615660845819875721L /* pi/4 */
454 # define M_1_PIl 0.318309886183790671537767526745028724L /* 1/pi */
455 # define M_2_PIl 0.636619772367581343075535053490057448L /* 2/pi */
456 # define M_2_SQRTPIl 1.128379167095512573896158903121545172L /* 2/sqrt(pi) */
457 # define M_SQRT2l 1.414213562373095048801688724209698079L /* sqrt(2) */
458 # define M_SQRT1_2l 0.707106781186547524400844362104849039L /* 1/sqrt(2) */
459 #endif
462 /* When compiling in strict ISO C compatible mode we must not use the
463 inline functions since they, among other things, do not set the
464 `errno' variable correctly. */
465 #if defined __STRICT_ANSI__ && !defined __NO_MATH_INLINES
466 # define __NO_MATH_INLINES 1
467 #endif
469 #if defined __USE_ISOC99 && __GNUC_PREREQ(2,97)
470 /* ISO C99 defines some macros to compare number while taking care for
471 unordered numbers. Many FPUs provide special instructions to support
472 these operations. Generic support in GCC for these as builtins went
473 in before 3.0.0, but not all cpus added their patterns. We define
474 versions that use the builtins here, and <bits/mathinline.h> will
475 undef/redefine as appropriate for the specific GCC version in use. */
476 # define isgreater(x, y) __builtin_isgreater(x, y)
477 # define isgreaterequal(x, y) __builtin_isgreaterequal(x, y)
478 # define isless(x, y) __builtin_isless(x, y)
479 # define islessequal(x, y) __builtin_islessequal(x, y)
480 # define islessgreater(x, y) __builtin_islessgreater(x, y)
481 # define isunordered(u, v) __builtin_isunordered(u, v)
482 #endif
484 /* Get machine-dependent inline versions (if there are any). */
485 #ifdef __USE_EXTERN_INLINES
486 # include <bits/mathinline.h>
487 #endif
489 /* Define special entry points to use when the compiler got told to
490 only expect finite results. */
491 #if defined __FINITE_MATH_ONLY__ && __FINITE_MATH_ONLY__ > 0
492 # include <bits/math-finite.h>
493 #endif
495 #ifdef __USE_ISOC99
496 /* If we've still got undefined comparison macros, provide defaults. */
498 /* Return nonzero value if X is greater than Y. */
499 # ifndef isgreater
500 # define isgreater(x, y) \
501 (__extension__ \
502 ({ __typeof__(x) __x = (x); __typeof__(y) __y = (y); \
503 !isunordered (__x, __y) && __x > __y; }))
504 # endif
506 /* Return nonzero value if X is greater than or equal to Y. */
507 # ifndef isgreaterequal
508 # define isgreaterequal(x, y) \
509 (__extension__ \
510 ({ __typeof__(x) __x = (x); __typeof__(y) __y = (y); \
511 !isunordered (__x, __y) && __x >= __y; }))
512 # endif
514 /* Return nonzero value if X is less than Y. */
515 # ifndef isless
516 # define isless(x, y) \
517 (__extension__ \
518 ({ __typeof__(x) __x = (x); __typeof__(y) __y = (y); \
519 !isunordered (__x, __y) && __x < __y; }))
520 # endif
522 /* Return nonzero value if X is less than or equal to Y. */
523 # ifndef islessequal
524 # define islessequal(x, y) \
525 (__extension__ \
526 ({ __typeof__(x) __x = (x); __typeof__(y) __y = (y); \
527 !isunordered (__x, __y) && __x <= __y; }))
528 # endif
530 /* Return nonzero value if either X is less than Y or Y is less than X. */
531 # ifndef islessgreater
532 # define islessgreater(x, y) \
533 (__extension__ \
534 ({ __typeof__(x) __x = (x); __typeof__(y) __y = (y); \
535 !isunordered (__x, __y) && (__x < __y || __y < __x); }))
536 # endif
538 /* Return nonzero value if arguments are unordered. */
539 # ifndef isunordered
540 # define isunordered(u, v) \
541 (__extension__ \
542 ({ __typeof__(u) __u = (u); __typeof__(v) __v = (v); \
543 fpclassify (__u) == FP_NAN || fpclassify (__v) == FP_NAN; }))
544 # endif
546 #endif
548 #if __GLIBC_USE (IEC_60559_BFP_EXT)
549 /* Return X == Y but raising "invalid" and setting errno if X or Y is
550 a NaN. */
551 # ifdef __NO_LONG_DOUBLE_MATH
552 # if (__FLT_EVAL_METHOD__ == 1 \
553 || __FLT_EVAL_METHOD__ == 2 \
554 || __FLT_EVAL_METHOD__ > 32)
555 # define iseqsig(x, y) __iseqsig ((x), (y))
556 # else
557 # define iseqsig(x, y) \
558 (sizeof ((x) + (y)) == sizeof (float) \
559 ? __iseqsigf ((x), (y)) \
560 : __iseqsig ((x), (y)))
561 # endif
562 # else
563 # if __FLT_EVAL_METHOD__ == 2 || __FLT_EVAL_METHOD__ > 64
564 # define iseqsig(x, y) __iseqsigl ((x), (y))
565 # elif __FLT_EVAL_METHOD__ == 1 || __FLT_EVAL_METHOD__ > 32
566 # define iseqsig(x, y) \
567 (sizeof ((x) + (y)) <= sizeof (double) \
568 ? __iseqsig ((x), (y)) \
569 : __iseqsigl ((x), (y)))
570 # else
571 # define iseqsig(x, y) \
572 (sizeof ((x) + (y)) == sizeof (float) \
573 ? __iseqsigf ((x), (y)) \
574 : sizeof ((x) + (y)) == sizeof (double) \
575 ? __iseqsig ((x), (y)) \
576 : __iseqsigl ((x), (y)))
577 # endif
578 # endif
579 #endif
581 __END_DECLS
584 #endif /* math.h */