summaryrefslogtreecommitdiffstats
path: root/Include/pyport.h
blob: 9df74ce9895340bef94cd4aed963cfa96dff19a3 (plain)
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
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
#ifndef Py_PYPORT_H
#define Py_PYPORT_H

#include "pyconfig.h" /* include for defines */

/* Some versions of HP-UX & Solaris need inttypes.h for int32_t,
   INT32_MAX, etc. */
#ifdef HAVE_INTTYPES_H
#include <inttypes.h>
#endif

#ifdef HAVE_STDINT_H
#include <stdint.h>
#endif

/**************************************************************************
Symbols and macros to supply platform-independent interfaces to basic
C language & library operations whose spellings vary across platforms.

Please try to make documentation here as clear as possible:  by definition,
the stuff here is trying to illuminate C's darkest corners.

Config #defines referenced here:

SIGNED_RIGHT_SHIFT_ZERO_FILLS
Meaning:  To be defined iff i>>j does not extend the sign bit when i is a
          signed integral type and i < 0.
Used in:  Py_ARITHMETIC_RIGHT_SHIFT

Py_DEBUG
Meaning:  Extra checks compiled in for debug mode.
Used in:  Py_SAFE_DOWNCAST

HAVE_UINTPTR_T
Meaning:  The C9X type uintptr_t is supported by the compiler
Used in:  Py_uintptr_t

HAVE_LONG_LONG
Meaning:  The compiler supports the C type "long long"
Used in:  PY_LONG_LONG

**************************************************************************/

/* typedefs for some C9X-defined synonyms for integral types.
 *
 * The names in Python are exactly the same as the C9X names, except with a
 * Py_ prefix.  Until C9X is universally implemented, this is the only way
 * to ensure that Python gets reliable names that don't conflict with names
 * in non-Python code that are playing their own tricks to define the C9X
 * names.
 *
 * NOTE: don't go nuts here!  Python has no use for *most* of the C9X
 * integral synonyms.  Only define the ones we actually need.
 */

#ifdef HAVE_LONG_LONG
#ifndef PY_LONG_LONG
#define PY_LONG_LONG long long
#if defined(LLONG_MAX)
/* If LLONG_MAX is defined in limits.h, use that. */
#define PY_LLONG_MIN LLONG_MIN
#define PY_LLONG_MAX LLONG_MAX
#define PY_ULLONG_MAX ULLONG_MAX
#elif defined(__LONG_LONG_MAX__)
/* Otherwise, if GCC has a builtin define, use that. */
#define PY_LLONG_MAX __LONG_LONG_MAX__
#define PY_LLONG_MIN (-PY_LLONG_MAX-1)
#define PY_ULLONG_MAX (__LONG_LONG_MAX__*2ULL + 1ULL)
#else
/* Otherwise, rely on two's complement. */
#define PY_ULLONG_MAX (~0ULL)
#define PY_LLONG_MAX  ((long long)(PY_ULLONG_MAX>>1))
#define PY_LLONG_MIN (-PY_LLONG_MAX-1)
#endif /* LLONG_MAX */
#endif
#endif /* HAVE_LONG_LONG */

/* a build with 30-bit digits for Python long integers needs an exact-width
 * 32-bit unsigned integer type to store those digits.  (We could just use
 * type 'unsigned long', but that would be wasteful on a system where longs
 * are 64-bits.)  On Unix systems, the autoconf macro AC_TYPE_UINT32_T defines
 * uint32_t to be such a type unless stdint.h or inttypes.h defines uint32_t.
 * However, it doesn't set HAVE_UINT32_T, so we do that here.
 */
#if (defined UINT32_MAX || defined uint32_t)
#ifndef PY_UINT32_T
#define HAVE_UINT32_T 1
#define PY_UINT32_T uint32_t
#endif
#endif

/* Macros for a 64-bit unsigned integer type; used for type 'twodigits' in the
 * long integer implementation, when 30-bit digits are enabled.
 */
#if (defined UINT64_MAX || defined uint64_t)
#ifndef PY_UINT64_T
#define HAVE_UINT64_T 1
#define PY_UINT64_T uint64_t
#endif
#endif

/* Signed variants of the above */
#if (defined INT32_MAX || defined int32_t)
#ifndef PY_INT32_T
#define HAVE_INT32_T 1
#define PY_INT32_T int32_t
#endif
#endif
#if (defined INT64_MAX || defined int64_t)
#ifndef PY_INT64_T
#define HAVE_INT64_T 1
#define PY_INT64_T int64_t
#endif
#endif

/* If PYLONG_BITS_IN_DIGIT is not defined then we'll use 30-bit digits if all
   the necessary integer types are available, and we're on a 64-bit platform
   (as determined by SIZEOF_VOID_P); otherwise we use 15-bit digits. */

#ifndef PYLONG_BITS_IN_DIGIT
#if (defined HAVE_UINT64_T && defined HAVE_INT64_T && \
     defined HAVE_UINT32_T && defined HAVE_INT32_T && SIZEOF_VOID_P >= 8)
#define PYLONG_BITS_IN_DIGIT 30
#else
#define PYLONG_BITS_IN_DIGIT 15
#endif
#endif

/* uintptr_t is the C9X name for an unsigned integral type such that a
 * legitimate void* can be cast to uintptr_t and then back to void* again
 * without loss of information.  Similarly for intptr_t, wrt a signed
 * integral type.
 */
#ifdef HAVE_UINTPTR_T
typedef uintptr_t	Py_uintptr_t;
typedef intptr_t	Py_intptr_t;

#elif SIZEOF_VOID_P <= SIZEOF_INT
typedef unsigned int	Py_uintptr_t;
typedef int		Py_intptr_t;

#elif SIZEOF_VOID_P <= SIZEOF_LONG
typedef unsigned long	Py_uintptr_t;
typedef long		Py_intptr_t;

#elif defined(HAVE_LONG_LONG) && (SIZEOF_VOID_P <= SIZEOF_LONG_LONG)
typedef unsigned PY_LONG_LONG	Py_uintptr_t;
typedef PY_LONG_LONG		Py_intptr_t;

#else
#   error "Python needs a typedef for Py_uintptr_t in pyport.h."
#endif /* HAVE_UINTPTR_T */

/* Py_ssize_t is a signed integral type such that sizeof(Py_ssize_t) ==
 * sizeof(size_t).  C99 doesn't define such a thing directly (size_t is an
 * unsigned integral type).  See PEP 353 for details.
 */
#ifdef HAVE_SSIZE_T
typedef ssize_t		Py_ssize_t;
#elif SIZEOF_VOID_P == SIZEOF_SIZE_T
typedef Py_intptr_t	Py_ssize_t;
#else
#   error "Python needs a typedef for Py_ssize_t in pyport.h."
#endif

/* Largest possible value of size_t.
   SIZE_MAX is part of C99, so it might be defined on some
   platforms. If it is not defined, (size_t)-1 is a portable
   definition for C89, due to the way signed->unsigned 
   conversion is defined. */
#ifdef SIZE_MAX
#define PY_SIZE_MAX SIZE_MAX
#else
#define PY_SIZE_MAX ((size_t)-1)
#endif

/* Largest positive value of type Py_ssize_t. */
#define PY_SSIZE_T_MAX ((Py_ssize_t)(((size_t)-1)>>1))
/* Smallest negative value of type Py_ssize_t. */
#define PY_SSIZE_T_MIN (-PY_SSIZE_T_MAX-1)

#if SIZEOF_PID_T > SIZEOF_LONG
#   error "Python doesn't support sizeof(pid_t) > sizeof(long)"
#endif

/* PY_FORMAT_SIZE_T is a platform-specific modifier for use in a printf
 * format to convert an argument with the width of a size_t or Py_ssize_t.
 * C99 introduced "z" for this purpose, but not all platforms support that;
 * e.g., MS compilers use "I" instead.
 *
 * These "high level" Python format functions interpret "z" correctly on
 * all platforms (Python interprets the format string itself, and does whatever
 * the platform C requires to convert a size_t/Py_ssize_t argument):
 *
 *     PyBytes_FromFormat
 *     PyErr_Format
 *     PyBytes_FromFormatV
 *     PyUnicode_FromFormatV
 *
 * Lower-level uses require that you interpolate the correct format modifier
 * yourself (e.g., calling printf, fprintf, sprintf, PyOS_snprintf); for
 * example,
 *
 *     Py_ssize_t index;
 *     fprintf(stderr, "index %" PY_FORMAT_SIZE_T "d sucks\n", index);
 *
 * That will expand to %ld, or %Id, or to something else correct for a
 * Py_ssize_t on the platform.
 */
#ifndef PY_FORMAT_SIZE_T
#   if SIZEOF_SIZE_T == SIZEOF_INT && !defined(__APPLE__)
#       define PY_FORMAT_SIZE_T ""
#   elif SIZEOF_SIZE_T == SIZEOF_LONG
#       define PY_FORMAT_SIZE_T "l"
#   elif defined(MS_WINDOWS)
#       define PY_FORMAT_SIZE_T "I"
#   else
#       error "This platform's pyconfig.h needs to define PY_FORMAT_SIZE_T"
#   endif
#endif

/* PY_FORMAT_LONG_LONG is analogous to PY_FORMAT_SIZE_T above, but for
 * the long long type instead of the size_t type.  It's only available
 * when HAVE_LONG_LONG is defined. The "high level" Python format
 * functions listed above will interpret "lld" or "llu" correctly on
 * all platforms.
 */
#ifdef HAVE_LONG_LONG
#   ifndef PY_FORMAT_LONG_LONG
#       if defined(MS_WIN64) || defined(MS_WINDOWS)
#           define PY_FORMAT_LONG_LONG "I64"
#       else
#           error "This platform's pyconfig.h needs to define PY_FORMAT_LONG_LONG"
#       endif
#   endif
#endif

/* Py_LOCAL can be used instead of static to get the fastest possible calling
 * convention for functions that are local to a given module.
 *
 * Py_LOCAL_INLINE does the same thing, and also explicitly requests inlining,
 * for platforms that support that.
 *
 * If PY_LOCAL_AGGRESSIVE is defined before python.h is included, more
 * "aggressive" inlining/optimizaion is enabled for the entire module.  This
 * may lead to code bloat, and may slow things down for those reasons.  It may
 * also lead to errors, if the code relies on pointer aliasing.  Use with
 * care.
 *
 * NOTE: You can only use this for functions that are entirely local to a
 * module; functions that are exported via method tables, callbacks, etc,
 * should keep using static.
 */

#undef USE_INLINE /* XXX - set via configure? */

#if defined(_MSC_VER)
#if defined(PY_LOCAL_AGGRESSIVE)
/* enable more aggressive optimization for visual studio */
#pragma optimize("agtw", on)
#endif
/* ignore warnings if the compiler decides not to inline a function */ 
#pragma warning(disable: 4710)
/* fastest possible local call under MSVC */
#define Py_LOCAL(type) static type __fastcall
#define Py_LOCAL_INLINE(type) static __inline type __fastcall
#elif defined(USE_INLINE)
#define Py_LOCAL(type) static type
#define Py_LOCAL_INLINE(type) static inline type
#else
#define Py_LOCAL(type) static type
#define Py_LOCAL_INLINE(type) static type
#endif

/* Py_MEMCPY can be used instead of memcpy in cases where the copied blocks
 * are often very short.  While most platforms have highly optimized code for
 * large transfers, the setup costs for memcpy are often quite high.  MEMCPY
 * solves this by doing short copies "in line".
 */

#if defined(_MSC_VER)
#define Py_MEMCPY(target, source, length) do {				\
		size_t i_, n_ = (length);				\
		char *t_ = (void*) (target);				\
		const char *s_ = (void*) (source);			\
		if (n_ >= 16)						\
			memcpy(t_, s_, n_);				\
		else							\
			for (i_ = 0; i_ < n_; i_++)			\
				t_[i_] = s_[i_];			\
	} while (0)
#else
#define Py_MEMCPY memcpy
#endif

#include <stdlib.h>

#ifdef HAVE_IEEEFP_H
#include <ieeefp.h>  /* needed for 'finite' declaration on some platforms */
#endif

#include <math.h> /* Moved here from the math section, before extern "C" */

/********************************************
 * WRAPPER FOR <time.h> and/or <sys/time.h> *
 ********************************************/

#ifdef TIME_WITH_SYS_TIME
#include <sys/time.h>
#include <time.h>
#else /* !TIME_WITH_SYS_TIME */
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#else /* !HAVE_SYS_TIME_H */
#include <time.h>
#endif /* !HAVE_SYS_TIME_H */
#endif /* !TIME_WITH_SYS_TIME */


/******************************
 * WRAPPER FOR <sys/select.h> *
 ******************************/

/* NB caller must include <sys/types.h> */

#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif /* !HAVE_SYS_SELECT_H */

/*******************************
 * stat() and fstat() fiddling *
 *******************************/

/* We expect that stat and fstat exist on most systems.
 *  It's confirmed on Unix, Mac and Windows.
 *  If you don't have them, add
 *      #define DONT_HAVE_STAT
 * and/or
 *      #define DONT_HAVE_FSTAT
 * to your pyconfig.h. Python code beyond this should check HAVE_STAT and
 * HAVE_FSTAT instead.
 * Also
 *      #define HAVE_SYS_STAT_H
 * if <sys/stat.h> exists on your platform, and
 *      #define HAVE_STAT_H
 * if <stat.h> does.
 */
#ifndef DONT_HAVE_STAT
#define HAVE_STAT
#endif

#ifndef DONT_HAVE_FSTAT
#define HAVE_FSTAT
#endif

#ifdef HAVE_SYS_STAT_H
#if defined(PYOS_OS2) && defined(PYCC_GCC)
#include <sys/types.h>
#endif
#include <sys/stat.h>
#elif defined(HAVE_STAT_H)
#include <stat.h>
#endif

#if defined(PYCC_VACPP)
/* VisualAge C/C++ Failed to Define MountType Field in sys/stat.h */
#define S_IFMT (S_IFDIR|S_IFCHR|S_IFREG)
#endif

#ifndef S_ISREG
#define S_ISREG(x) (((x) & S_IFMT) == S_IFREG)
#endif

#ifndef S_ISDIR
#define S_ISDIR(x) (((x) & S_IFMT) == S_IFDIR)
#endif


#ifdef __cplusplus
/* Move this down here since some C++ #include's don't like to be included
   inside an extern "C" */
extern "C" {
#endif


/* Py_ARITHMETIC_RIGHT_SHIFT
 * C doesn't define whether a right-shift of a signed integer sign-extends
 * or zero-fills.  Here a macro to force sign extension:
 * Py_ARITHMETIC_RIGHT_SHIFT(TYPE, I, J)
 *    Return I >> J, forcing sign extension.  Arithmetically, return the
 *    floor of I/2**J.
 * Requirements:
 *    I should have signed integer type.  In the terminology of C99, this can
 *    be either one of the five standard signed integer types (signed char,
 *    short, int, long, long long) or an extended signed integer type.
 *    J is an integer >= 0 and strictly less than the number of bits in the
 *    type of I (because C doesn't define what happens for J outside that
 *    range either).
 *    TYPE used to specify the type of I, but is now ignored.  It's been left
 *    in for backwards compatibility with versions <= 2.6 or 3.0.
 * Caution:
 *    I may be evaluated more than once.
 */
#ifdef SIGNED_RIGHT_SHIFT_ZERO_FILLS
#define Py_ARITHMETIC_RIGHT_SHIFT(TYPE, I, J) \
	((I) < 0 ? -1-((-1-(I)) >> (J)) : (I) >> (J))
#else
#define Py_ARITHMETIC_RIGHT_SHIFT(TYPE, I, J) ((I) >> (J))
#endif

/* Py_FORCE_EXPANSION(X)
 * "Simply" returns its argument.  However, macro expansions within the
 * argument are evaluated.  This unfortunate trickery is needed to get
 * token-pasting to work as desired in some cases.
 */
#define Py_FORCE_EXPANSION(X) X

/* Py_SAFE_DOWNCAST(VALUE, WIDE, NARROW)
 * Cast VALUE to type NARROW from type WIDE.  In Py_DEBUG mode, this
 * assert-fails if any information is lost.
 * Caution:
 *    VALUE may be evaluated more than once.
 */
#ifdef Py_DEBUG
#define Py_SAFE_DOWNCAST(VALUE, WIDE, NARROW) \
	(assert((WIDE)(NARROW)(VALUE) == (VALUE)), (NARROW)(VALUE))
#else
#define Py_SAFE_DOWNCAST(VALUE, WIDE, NARROW) (NARROW)(VALUE)
#endif

/* Py_SET_ERRNO_ON_MATH_ERROR(x)
 * If a libm function did not set errno, but it looks like the result
 * overflowed or not-a-number, set errno to ERANGE or EDOM.  Set errno
 * to 0 before calling a libm function, and invoke this macro after,
 * passing the function result.
 * Caution:
 *    This isn't reliable.  See Py_OVERFLOWED comments.
 *    X is evaluated more than once.
 */
#if defined(__FreeBSD__) || defined(__OpenBSD__) || (defined(__hpux) && defined(__ia64))
#define _Py_SET_EDOM_FOR_NAN(X) if (isnan(X)) errno = EDOM;
#else
#define _Py_SET_EDOM_FOR_NAN(X) ;
#endif
#define Py_SET_ERRNO_ON_MATH_ERROR(X) \
	do { \
		if (errno == 0) { \
			if ((X) == Py_HUGE_VAL || (X) == -Py_HUGE_VAL) \
				errno = ERANGE; \
			else _Py_SET_EDOM_FOR_NAN(X) \
		} \
	} while(0)

/* Py_SET_ERANGE_ON_OVERFLOW(x)
 * An alias of Py_SET_ERRNO_ON_MATH_ERROR for backward-compatibility.
 */
#define Py_SET_ERANGE_IF_OVERFLOW(X) Py_SET_ERRNO_ON_MATH_ERROR(X)

/* Py_ADJUST_ERANGE1(x)
 * Py_ADJUST_ERANGE2(x, y)
 * Set errno to 0 before calling a libm function, and invoke one of these
 * macros after, passing the function result(s) (Py_ADJUST_ERANGE2 is useful
 * for functions returning complex results).  This makes two kinds of
 * adjustments to errno:  (A) If it looks like the platform libm set
 * errno=ERANGE due to underflow, clear errno. (B) If it looks like the
 * platform libm overflowed but didn't set errno, force errno to ERANGE.  In
 * effect, we're trying to force a useful implementation of C89 errno
 * behavior.
 * Caution:
 *    This isn't reliable.  See Py_OVERFLOWED comments.
 *    X and Y may be evaluated more than once.
 */
#define Py_ADJUST_ERANGE1(X)						\
	do {								\
		if (errno == 0) {					\
			if ((X) == Py_HUGE_VAL || (X) == -Py_HUGE_VAL)	\
				errno = ERANGE;				\
		}							\
		else if (errno == ERANGE && (X) == 0.0)			\
			errno = 0;					\
	} while(0)

#define Py_ADJUST_ERANGE2(X, Y)						\
	do {								\
		if ((X) == Py_HUGE_VAL || (X) == -Py_HUGE_VAL ||	\
		    (Y) == Py_HUGE_VAL || (Y) == -Py_HUGE_VAL) {	\
				if (errno == 0)				\
					errno = ERANGE;			\
		}							\
		else if (errno == ERANGE)				\
			errno = 0;					\
	} while(0)

/*  The functions _Py_dg_strtod and _Py_dg_dtoa in Python/dtoa.c (which are
 *  required to support the short float repr introduced in Python 3.1) require
 *  that the floating-point unit that's being used for arithmetic operations
 *  on C doubles is set to use 53-bit precision.  It also requires that the
 *  FPU rounding mode is round-half-to-even, but that's less often an issue.
 *
 *  If your FPU isn't already set to 53-bit precision/round-half-to-even, and
 *  you want to make use of _Py_dg_strtod and _Py_dg_dtoa, then you should
 *
 *     #define HAVE_PY_SET_53BIT_PRECISION 1
 *
 *  and also give appropriate definitions for the following three macros:
 *
 *    _PY_SET_53BIT_PRECISION_START : store original FPU settings, and
 *        set FPU to 53-bit precision/round-half-to-even
 *    _PY_SET_53BIT_PRECISION_END : restore original FPU settings
 *    _PY_SET_53BIT_PRECISION_HEADER : any variable declarations needed to
 *        use the two macros above.
 *
 * The macros are designed to be used within a single C function: see
 * Python/pystrtod.c for an example of their use.
 */

/* get and set x87 control word for gcc/x86 */
#ifdef HAVE_GCC_ASM_FOR_X87
#define HAVE_PY_SET_53BIT_PRECISION 1
/* _Py_get/set_387controlword functions are defined in Python/pymath.c */
#define _Py_SET_53BIT_PRECISION_HEADER				\
	unsigned short old_387controlword, new_387controlword
#define _Py_SET_53BIT_PRECISION_START					\
	do {								\
		old_387controlword = _Py_get_387controlword();		\
		new_387controlword = (old_387controlword & ~0x0f00) | 0x0200; \
		if (new_387controlword != old_387controlword)		\
			_Py_set_387controlword(new_387controlword);	\
	} while (0)
#define _Py_SET_53BIT_PRECISION_END				\
	if (new_387controlword != old_387controlword)		\
		_Py_set_387controlword(old_387controlword)
#endif

/* default definitions are empty */
#ifndef HAVE_PY_SET_53BIT_PRECISION
#define _Py_SET_53BIT_PRECISION_HEADER
#define _Py_SET_53BIT_PRECISION_START
#define _Py_SET_53BIT_PRECISION_END
#endif

/* If we can't guarantee 53-bit precision, don't use the code
   in Python/dtoa.c, but fall back to standard code.  This
   means that repr of a float will be long (17 sig digits).

   Realistically, there are two things that could go wrong:

   (1) doubles aren't IEEE 754 doubles, or
   (2) we're on x86 with the rounding precision set to 64-bits
       (extended precision), and we don't know how to change
       the rounding precision.
 */

#if !defined(DOUBLE_IS_LITTLE_ENDIAN_IEEE754) && \
    !defined(DOUBLE_IS_BIG_ENDIAN_IEEE754) && \
    !defined(DOUBLE_IS_ARM_MIXED_ENDIAN_IEEE754)
#define PY_NO_SHORT_FLOAT_REPR
#endif

/* double rounding is symptomatic of use of extended precision on x86.  If
   we're seeing double rounding, and we don't have any mechanism available for
   changing the FPU rounding precision, then don't use Python/dtoa.c. */
#if defined(X87_DOUBLE_ROUNDING) && !defined(HAVE_PY_SET_53BIT_PRECISION)
#define PY_NO_SHORT_FLOAT_REPR
#endif


/* Py_DEPRECATED(version)
 * Declare a variable, type, or function deprecated.
 * Usage:
 *    extern int old_var Py_DEPRECATED(2.3);
 *    typedef int T1 Py_DEPRECATED(2.4);
 *    extern int x() Py_DEPRECATED(2.5);
 */
#if defined(__GNUC__) && ((__GNUC__ >= 4) || \
			  (__GNUC__ == 3) && (__GNUC_MINOR__ >= 1))
#define Py_DEPRECATED(VERSION_UNUSED) __attribute__((__deprecated__))
#else
#define Py_DEPRECATED(VERSION_UNUSED)
#endif

/**************************************************************************
Prototypes that are missing from the standard include files on some systems
(and possibly only some versions of such systems.)

Please be conservative with adding new ones, document them and enclose them
in platform-specific #ifdefs.
**************************************************************************/

#ifdef SOLARIS
/* Unchecked */
extern int gethostname(char *, int);
#endif

#ifdef HAVE__GETPTY
#include <sys/types.h>		/* we need to import mode_t */
extern char * _getpty(int *, int, mode_t, int);
#endif

/* On QNX 6, struct termio must be declared by including sys/termio.h
   if TCGETA, TCSETA, TCSETAW, or TCSETAF are used.  sys/termio.h must
   be included before termios.h or it will generate an error. */
#ifdef HAVE_SYS_TERMIO_H
#include <sys/termio.h>
#endif

#if defined(HAVE_OPENPTY) || defined(HAVE_FORKPTY)
#if !defined(HAVE_PTY_H) && !defined(HAVE_LIBUTIL_H)
/* BSDI does not supply a prototype for the 'openpty' and 'forkpty'
   functions, even though they are included in libutil. */
#include <termios.h>
extern int openpty(int *, int *, char *, struct termios *, struct winsize *);
extern pid_t forkpty(int *, char *, struct termios *, struct winsize *);
#endif /* !defined(HAVE_PTY_H) && !defined(HAVE_LIBUTIL_H) */
#endif /* defined(HAVE_OPENPTY) || defined(HAVE_FORKPTY) */


/* On 4.4BSD-descendants, ctype functions serves the whole range of
 * wchar_t character set rather than single byte code points only.
 * This characteristic can break some operations of string object
 * including str.upper() and str.split() on UTF-8 locales.  This
 * workaround was provided by Tim Robbins of FreeBSD project.
 */

#ifdef __FreeBSD__
#include <osreldate.h>
#if __FreeBSD_version > 500039
#include <ctype.h>
#include <wctype.h>
#undef isalnum
#define isalnum(c) iswalnum(btowc(c))
#undef isalpha
#define isalpha(c) iswalpha(btowc(c))
#undef islower
#define islower(c) iswlower(btowc(c))
#undef isspace
#define isspace(c) iswspace(btowc(c))
#undef isupper
#define isupper(c) iswupper(btowc(c))
#undef tolower
#define tolower(c) towlower(btowc(c))
#undef toupper
#define toupper(c) towupper(btowc(c))
#endif
#endif


/* Declarations for symbol visibility.

  PyAPI_FUNC(type): Declares a public Python API function and return type
  PyAPI_DATA(type): Declares public Python data and its type
  PyMODINIT_FUNC:   A Python module init function.  If these functions are
                    inside the Python core, they are private to the core.
                    If in an extension module, it may be declared with
                    external linkage depending on the platform.

  As a number of platforms support/require "__declspec(dllimport/dllexport)",
  we support a HAVE_DECLSPEC_DLL macro to save duplication.
*/

/*
  All windows ports, except cygwin, are handled in PC/pyconfig.h.

  Cygwin is the only other autoconf platform requiring special
  linkage handling and it uses __declspec().
*/
#if defined(__CYGWIN__)
#	define HAVE_DECLSPEC_DLL
#endif

/* only get special linkage if built as shared or platform is Cygwin */
#if defined(Py_ENABLE_SHARED) || defined(__CYGWIN__)
#	if defined(HAVE_DECLSPEC_DLL)
#		ifdef Py_BUILD_CORE
#			define PyAPI_FUNC(RTYPE) __declspec(dllexport) RTYPE
#			define PyAPI_DATA(RTYPE) extern __declspec(dllexport) RTYPE
			/* module init functions inside the core need no external linkage */
			/* except for Cygwin to handle embedding */
#			if defined(__CYGWIN__)
#				define PyMODINIT_FUNC __declspec(dllexport) PyObject*
#			else /* __CYGWIN__ */
#				define PyMODINIT_FUNC PyObject*
#			endif /* __CYGWIN__ */
#		else /* Py_BUILD_CORE */
			/* Building an extension module, or an embedded situation */
			/* public Python functions and data are imported */
			/* Under Cygwin, auto-import functions to prevent compilation */
			/* failures similar to http://python.org/doc/FAQ.html#3.24 */
#			if !defined(__CYGWIN__)
#				define PyAPI_FUNC(RTYPE) __declspec(dllimport) RTYPE
#			endif /* !__CYGWIN__ */
#			define PyAPI_DATA(RTYPE) extern __declspec(dllimport) RTYPE
			/* module init functions outside the core must be exported */
#			if defined(__cplusplus)
#				define PyMODINIT_FUNC extern "C" __declspec(dllexport) PyObject*
#			else /* __cplusplus */
#				define PyMODINIT_FUNC __declspec(dllexport) PyObject*
#			endif /* __cplusplus */
#		endif /* Py_BUILD_CORE */
#	endif /* HAVE_DECLSPEC */
#endif /* Py_ENABLE_SHARED */

/* If no external linkage macros defined by now, create defaults */
#ifndef PyAPI_FUNC
#	define PyAPI_FUNC(RTYPE) RTYPE
#endif
#ifndef PyAPI_DATA
#	define PyAPI_DATA(RTYPE) extern RTYPE
#endif
#ifndef PyMODINIT_FUNC
#	if defined(__cplusplus)
#		define PyMODINIT_FUNC extern "C" PyObject*
#	else /* __cplusplus */
#		define PyMODINIT_FUNC PyObject*
#	endif /* __cplusplus */
#endif

/* limits.h constants that may be missing */

#ifndef INT_MAX
#define INT_MAX 2147483647
#endif

#ifndef LONG_MAX
#if SIZEOF_LONG == 4
#define LONG_MAX 0X7FFFFFFFL
#elif SIZEOF_LONG == 8
#define LONG_MAX 0X7FFFFFFFFFFFFFFFL
#else
#error "could not set LONG_MAX in pyport.h"
#endif
#endif

#ifndef LONG_MIN
#define LONG_MIN (-LONG_MAX-1)
#endif

#ifndef LONG_BIT
#define LONG_BIT (8 * SIZEOF_LONG)
#endif

#if LONG_BIT != 8 * SIZEOF_LONG
/* 04-Oct-2000 LONG_BIT is apparently (mis)defined as 64 on some recent
 * 32-bit platforms using gcc.  We try to catch that here at compile-time
 * rather than waiting for integer multiplication to trigger bogus
 * overflows.
 */
#error "LONG_BIT definition appears wrong for platform (bad gcc/glibc config?)."
#endif

#ifdef __cplusplus
}
#endif

/*
 * Hide GCC attributes from compilers that don't support them.
 */
#if (!defined(__GNUC__) || __GNUC__ < 2 || \
     (__GNUC__ == 2 && __GNUC_MINOR__ < 7) )
#define Py_GCC_ATTRIBUTE(x)
#else
#define Py_GCC_ATTRIBUTE(x) __attribute__(x)
#endif

/*
 * Add PyArg_ParseTuple format where available.
 */
#ifdef HAVE_ATTRIBUTE_FORMAT_PARSETUPLE
#define Py_FORMAT_PARSETUPLE(func,p1,p2) __attribute__((format(func,p1,p2)))
#else
#define Py_FORMAT_PARSETUPLE(func,p1,p2)
#endif

/*
 * Specify alignment on compilers that support it.
 */
#if defined(__GNUC__) && __GNUC__ >= 3
#define Py_ALIGNED(x) __attribute__((aligned(x)))
#else
#define Py_ALIGNED(x)
#endif

/* Eliminate end-of-loop code not reached warnings from SunPro C
 * when using do{...}while(0) macros
 */
#ifdef __SUNPRO_C
#pragma error_messages (off,E_END_OF_LOOP_CODE_NOT_REACHED)
#endif

/*
 * Older Microsoft compilers don't support the C99 long long literal suffixes,
 * so these will be defined in PC/pyconfig.h for those compilers.
 */
#ifndef Py_LL
#define Py_LL(x) x##LL
#endif

#ifndef Py_ULL
#define Py_ULL(x) Py_LL(x##U)
#endif

#endif /* Py_PYPORT_H */