summaryrefslogtreecommitdiffstats
path: root/Include/pyport.h
blob: b68a3b49602ec9a597cd70f0a91a44de7f8184d4 (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
#ifndef Py_PYPORT_H
#define Py_PYPORT_H

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

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

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


/* For backward compatibility only. Obsolete, do not use. */
#ifdef HAVE_PROTOTYPES
#define Py_PROTO(x) x
#else
#define Py_PROTO(x) ()
#endif
#ifndef Py_FPROTO
#define Py_FPROTO(x) Py_PROTO(x)
#endif

/* 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
#endif
#endif /* HAVE_LONG_LONG */

/* 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 */

#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#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 DONT_HAVE_SYS_STAT_H
 * if <sys/stat.h> doesn't exist on your platform, and
 *      #define HAVE_STAT_H
 * if <stat.h> does (don't look at me -- ths mess is inherited).
 */
#ifndef DONT_HAVE_STAT
#define HAVE_STAT
#endif

#ifndef DONT_HAVE_FSTAT
#define HAVE_FSTAT
#endif

#ifdef RISCOS
#include <sys/types.h>
#endif

#ifndef DONT_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.
 * Requirements:
 *    I is of basic signed type TYPE (char, short, int, long, or long long).
 *    TYPE is one of char, short, int, long, or long long, although long long
 *    must not be used except on platforms that support it.
 *    J is an integer >= 0 and strictly less than the number of bits in TYPE
 *    (because C doesn't define what happens for J outside that range either).
 * Caution:
 *    I may be evaluated more than once.
 */
#ifdef SIGNED_RIGHT_SHIFT_ZERO_FILLS
#define Py_ARITHMETIC_RIGHT_SHIFT(TYPE, I, J) \
	((I) < 0 ? ~((~(unsigned TYPE)(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_IS_INFINITY(X)
 * Return 1 if float or double arg is an infinity, else 0.
 * Caution:
 *    X is evaluated more than once.
 *    This implementation may set the underflow flag if |X| is very small;
 *    it really can't be implemented correctly (& easily) before C99.
 */
#define Py_IS_INFINITY(X) ((X) && (X)*0.5 == (X))

/* HUGE_VAL is supposed to expand to a positive double infinity.  Python
 * uses Py_HUGE_VAL instead because some platforms are broken in this
 * respect.  We used to embed code in pyport.h to try to worm around that,
 * but different platforms are broken in conflicting ways.  If you're on
 * a platform where HUGE_VAL is defined incorrectly, fiddle your Python
 * config to #define Py_HUGE_VAL to something that works on your platform.
 */
#ifndef Py_HUGE_VAL
#define Py_HUGE_VAL HUGE_VAL
#endif

/* Py_OVERFLOWED(X)
 * Return 1 iff a libm function overflowed.  Set errno to 0 before calling
 * a libm function, and invoke this macro after, passing the function
 * result.
 * Caution:
 *    This isn't reliable.  C99 no longer requires libm to set errno under
 *	  any exceptional condition, but does require +- HUGE_VAL return
 *	  values on overflow.  A 754 box *probably* maps HUGE_VAL to a
 *	  double infinity, and we're cool if that's so, unless the input
 *	  was an infinity and an infinity is the expected result.  A C89
 *	  system sets errno to ERANGE, so we check for that too.  We're
 *	  out of luck if a C99 754 box doesn't map HUGE_VAL to +Inf, or
 *	  if the returned result is a NaN, or if a C89 box returns HUGE_VAL
 *	  in non-overflow cases.
 *    X is evaluated more than once.
 * Some platforms have better way to spell this, so expect some #ifdef'ery.
 */
#ifdef __FreeBSD__
#define Py_OVERFLOWED(X) isinf(X)
#else
#define Py_OVERFLOWED(X) ((X) != 0.0 && (errno == ERANGE ||    \
					 (X) == Py_HUGE_VAL || \
					 (X) == -Py_HUGE_VAL))
#endif

/* Py_SET_ERANGE_ON_OVERFLOW(x)
 * If a libm function did not set errno, but it looks like the result
 * overflowed, set errno to ERANGE.  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.
 */
#define Py_SET_ERANGE_IF_OVERFLOW(X) \
	do { \
		if (errno == 0 && ((X) == Py_HUGE_VAL ||  \
				   (X) == -Py_HUGE_VAL))  \
			errno = ERANGE; \
	} while(0)

/* 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)

/* 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__ == 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 __BEOS__
/* Unchecked */
/* It's in the libs, but not the headers... - [cjh] */
int shutdown( int, int );
#endif

#ifdef HAVE__GETPTY
#include <sys/types.h>		/* we need to import mode_t */
extern char * _getpty(int *, int, mode_t, int);
#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 int forkpty(int *, char *, struct termios *, struct winsize *);
#endif /* !defined(HAVE_PTY_H) && !defined(HAVE_LIBUTIL_H) */
#endif /* defined(HAVE_OPENPTY) || defined(HAVE_FORKPTY) */


/* These are pulled from various places. It isn't obvious on what platforms
   they are necessary, nor what the exact prototype should look like (which
   is likely to vary between platforms!) If you find you need one of these
   declarations, please move them to a platform-specific block and include
   proper prototypes. */
#if 0

/* From Modules/resource.c */
extern int getrusage();
extern int getpagesize();

/* From Python/sysmodule.c and Modules/posixmodule.c */
extern int fclose(FILE *);

/* From Modules/posixmodule.c */
extern int fdatasync(int);
/* XXX These are supposedly for SunOS4.1.3 but "shouldn't hurt elsewhere" */
extern int rename(const char *, const char *);
extern int pclose(FILE *);
extern int lstat(const char *, struct stat *);
extern int symlink(const char *, const char *);
extern int fsync(int fd);

#endif /* 0 */


/************************
 * WRAPPER FOR <math.h> *
 ************************/

#ifndef HAVE_HYPOT
extern double hypot(double, double);
#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.

  BeOS and cygwin are the only other autoconf platform requiring special
  linkage handling and both of these use __declspec().
*/
#if defined(__CYGWIN__) || defined(__BEOS__)
#	define HAVE_DECLSPEC_DLL
#endif

#if defined(Py_ENABLE_SHARED) /* only get special linkage if built as shared */
#	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 */
#			define PyMODINIT_FUNC void
#		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) void
#			else /* __cplusplus */
#				define PyMODINIT_FUNC __declspec(dllexport) void
#			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" void
#	else /* __cplusplus */
#		define PyMODINIT_FUNC void
#	endif /* __cplusplus */
#endif

/* Deprecated DL_IMPORT and DL_EXPORT macros */
#if defined(Py_ENABLE_SHARED) && defined (HAVE_DECLSPEC_DLL)
#	if defined(Py_BUILD_CORE)
#		define DL_IMPORT(RTYPE) __declspec(dllexport) RTYPE
#		define DL_EXPORT(RTYPE) __declspec(dllexport) RTYPE
#	else
#		define DL_IMPORT(RTYPE) __declspec(dllimport) RTYPE
#		define DL_EXPORT(RTYPE) __declspec(dllexport) RTYPE
#	endif
#endif
#ifndef DL_EXPORT
#	define DL_EXPORT(RTYPE) RTYPE
#endif
#ifndef DL_IMPORT
#	define DL_IMPORT(RTYPE) RTYPE
#endif
/* End of deprecated DL_* macros */

/* If the fd manipulation macros aren't defined,
   here is a set that should do the job */

#if 0 /* disabled and probably obsolete */

#ifndef	FD_SETSIZE
#define	FD_SETSIZE	256
#endif

#ifndef FD_SET

typedef long fd_mask;

#define NFDBITS	(sizeof(fd_mask) * NBBY)	/* bits per mask */
#ifndef howmany
#define	howmany(x, y)	(((x)+((y)-1))/(y))
#endif /* howmany */

typedef	struct fd_set {
	fd_mask	fds_bits[howmany(FD_SETSIZE, NFDBITS)];
} fd_set;

#define	FD_SET(n, p)	((p)->fds_bits[(n)/NFDBITS] |= (1 << ((n) % NFDBITS)))
#define	FD_CLR(n, p)	((p)->fds_bits[(n)/NFDBITS] &= ~(1 << ((n) % NFDBITS)))
#define	FD_ISSET(n, p)	((p)->fds_bits[(n)/NFDBITS] & (1 << ((n) % NFDBITS)))
#define FD_ZERO(p)	memset((char *)(p), '\0', sizeof(*(p)))

#endif /* FD_SET */

#endif /* fd manipulation macros */


/* 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) ) && \
    !defined(RISCOS)
#define Py_GCC_ATTRIBUTE(x)
#else
#define Py_GCC_ATTRIBUTE(x) __attribute__(x)
#endif

#endif /* Py_PYPORT_H */