Include/pyport.h

   1 /***********************************************************
   2 Copyright (c) 2000, BeOpen.com.
   3 All rights reserved.
   4
   5 See the file "Misc/COPYRIGHT" for information on usage and
   6 redistribution of this file, and for a DISCLAIMER OF ALL WARRANTIES.
   7 ******************************************************************/
   8
   9 #ifndef Py_PYPORT_H
  10 #define Py_PYPORT_H
  11
  12 #include "config.h" /* include for defines */
  13
  14 /**************************************************************************
  15 Symbols and macros to supply platform-independent interfaces to basic
  16 C language & library operations whose spellings vary across platforms.
  17
  18 Please try to make documentation here as clear as possible:  by definition,
  19 the stuff here is trying to illuminate C's darkest corners.
  20
  21 Config #defines referenced here:
  22
  23 SIGNED_RIGHT_SHIFT_ZERO_FILLS
  24 Meaning:  To be defined iff i>>j does not extend the sign bit when i is a
  25           signed integral type and i < 0.
  26 Used in:  Py_ARITHMETIC_RIGHT_SHIFT
  27
  28 Py_DEBUG
  29 Meaning:  Extra checks compiled in for debug mode.
  30 Used in:  Py_SAFE_DOWNCAST
  31
  32 HAVE_UINTPTR_T
  33 Meaning:  The C9X type uintptr_t is supported by the compiler
  34 Used in:  Py_uintptr_t
  35
  36 HAVE_LONG_LONG
  37 Meaning:  The compiler supports the C type "long long"
  38 Used in:  LONG_LONG
  39
  40 **************************************************************************/
  41
  42
  43 #define ANY void /* For API compatibility only. Obsolete, do not use. */
  44
  45 /* typedefs for some C9X-defined synonyms for integral types.
  46  *
  47  * The names in Python are exactly the same as the C9X names, except with a
  48  * Py_ prefix.  Until C9X is universally implemented, this is the only way
  49  * to ensure that Python gets reliable names that don't conflict with names
  50  * in non-Python code that are playing their own tricks to define the C9X
  51  * names.
  52  *
  53  * NOTE: don't go nuts here!  Python has no use for *most* of the C9X
  54  * integral synonyms.  Only define the ones we actually need.
  55  */
  56
  57 #ifdef HAVE_LONG_LONG
  58 #ifndef LONG_LONG
  59 #define LONG_LONG long long
  60 #endif
  61 #endif /* HAVE_LONG_LONG */
  62
  63 /* uintptr_t is the C9X name for an unsigned integral type such that a
  64  * legitimate void* can be cast to uintptr_t and then back to void* again
  65  * without loss of information.
  66  */
  67 #ifdef HAVE_UINTPTR_T
  68 typedef uintptr_t Py_uintptr_t;
  69 #elif SIZEOF_VOID_P <= SIZEOF_INT
  70 typedef unsigned int Py_uintptr_t;
  71 #elif SIZEOF_VOID_P <= SIZEOF_LONG
  72 typedef unsigned long Py_uintptr_t;
  73 #elif defined(HAVE_LONG_LONG) && (SIZEOF_VOID_P <= SIZEOF_LONG_LONG)
  74 typedef unsigned LONG_LONG Py_uintptr_t;
  75 #else
  76 #   error "Python needs a typedef for Py_uintptr_t in pyport.h."
  77 #endif /* HAVE_UINTPTR_T */
  78
  79 #ifdef HAVE_STDLIB_H
  80 #include <stdlib.h>
  81 #endif
  82
  83 #include <math.h> /* Moved here from the math section, before extern "C" */
  84
  85 /********************************************
  86  * WRAPPER FOR <time.h> and/or <sys/time.h> *
  87  ********************************************/
  88
  89 #ifdef TIME_WITH_SYS_TIME
  90 #include <sys/time.h>
  91 #include <time.h>
  92 #else /* !TIME_WITH_SYS_TIME */
  93 #ifdef HAVE_SYS_TIME_H
  94 #include <sys/time.h>
  95 #else /* !HAVE_SYS_TIME_H */
  96 #include <time.h>
  97 #endif /* !HAVE_SYS_TIME_H */
  98 #endif /* !TIME_WITH_SYS_TIME */
  99
 100
 101 /******************************
 102  * WRAPPER FOR <sys/select.h> *
 103  ******************************/
 104
 105 /* NB caller must include <sys/types.h> */
 106
 107 #ifdef HAVE_SYS_SELECT_H
 108
 109 #include <sys/select.h>
 110
 111 #else /* !HAVE_SYS_SELECT_H */
 112
 113 #ifdef USE_GUSI1
 114 /* If we don't have sys/select the definition may be in unistd.h */
 115 #include <GUSI.h>
 116 #endif
 117
 118 #endif /* !HAVE_SYS_SELECT_H */
 119
 120
 121 #ifdef __cplusplus
 122 /* Move this down here since some C++ #include's don't like to be included
 123    inside an extern "C" */
 124 extern "C" {
 125 #endif
 126
 127
 128 /* Py_ARITHMETIC_RIGHT_SHIFT
 129  * C doesn't define whether a right-shift of a signed integer sign-extends
 130  * or zero-fills.  Here a macro to force sign extension:
 131  * Py_ARITHMETIC_RIGHT_SHIFT(TYPE, I, J)
 132  *    Return I >> J, forcing sign extension.
 133  * Requirements:
 134  *    I is of basic signed type TYPE (char, short, int, long, or long long).
 135  *    TYPE is one of char, short, int, long, or long long, although long long
 136  *    must not be used except on platforms that support it.
 137  *    J is an integer >= 0 and strictly less than the number of bits in TYPE
 138  *    (because C doesn't define what happens for J outside that range either).
 139  * Caution:
 140  *    I may be evaluated more than once.
 141  */
 142 #ifdef SIGNED_RIGHT_SHIFT_ZERO_FILLS
 143 #define Py_ARITHMETIC_RIGHT_SHIFT(TYPE, I, J) \
 144         ((I) < 0 ? ~((~(unsigned TYPE)(I)) >> (J)) : (I) >> (J))
 145 #else
 146 #define Py_ARITHMETIC_RIGHT_SHIFT(TYPE, I, J) ((I) >> (J))
 147 #endif
 148
 149 /* Py_FORCE_EXPANSION(X)
 150  * "Simply" returns its argument.  However, macro expansions within the
 151  * argument are evaluated.  This unfortunate trickery is needed to get
 152  * token-pasting to work as desired in some cases.
 153  */
 154 #define Py_FORCE_EXPANSION(X) X
 155
 156 /* Py_SAFE_DOWNCAST(VALUE, WIDE, NARROW)
 157  * Cast VALUE to type NARROW from type WIDE.  In Py_DEBUG mode, this
 158  * assert-fails if any information is lost.
 159  * Caution:
 160  *    VALUE may be evaluated more than once.
 161  */
 162 #ifdef Py_DEBUG
 163 #define Py_SAFE_DOWNCAST(VALUE, WIDE, NARROW) \
 164         (assert((WIDE)(NARROW)(VALUE) == (VALUE)), (NARROW)(VALUE))
 165 #else
 166 #define Py_SAFE_DOWNCAST(VALUE, WIDE, NARROW) (NARROW)(VALUE)
 167 #endif
 168
 169 /* Py_IS_INFINITY(X)
 170  * Return 1 if float or double arg is an infinity, else 0.
 171  * Caution:
 172  *    X is evaluated more than once.
 173  *    This implementation may set the underflow flag if |X| is very small;
 174  *    it really can't be implemented correctly (& easily) before C99.
 175  */
 176  #define Py_IS_INFINITY(X) ((X) && (X)*0.5 == (X))
 177
 178 /**************************************************************************
 179 Prototypes that are missing from the standard include files on some systems
 180 (and possibly only some versions of such systems.)
 181
 182 Please be conservative with adding new ones, document them and enclose them
 183 in platform-specific #ifdefs.
 184 **************************************************************************/
 185
 186 #ifdef SOLARIS
 187 /* Unchecked */
 188 extern int gethostname(char *, int);
 189 #endif
 190
 191 #ifdef __BEOS__
 192 /* Unchecked */
 193 /* It's in the libs, but not the headers... - [cjh] */
 194 int shutdown( int, int );
 195 #endif
 196
 197 #ifdef HAVE__GETPTY
 198 #include <sys/types.h>          /* we need to import mode_t */
 199 extern char * _getpty(int *, int, mode_t, int);
 200 #endif
 201
 202 #if defined(HAVE_OPENPTY) || defined(HAVE_FORKPTY)
 203 #if !defined(HAVE_PTY_H) && !defined(HAVE_LIBUTIL_H)
 204 /* BSDI does not supply a prototype for the 'openpty' and 'forkpty'
 205    functions, even though they are included in libutil. */
 206 #include <termios.h>
 207 extern int openpty(int *, int *, char *, struct termios *, struct winsize *);
 208 extern int forkpty(int *, char *, struct termios *, struct winsize *);
 209 #endif /* !defined(HAVE_PTY_H) && !defined(HAVE_LIBUTIL_H) */
 210 #endif /* defined(HAVE_OPENPTY) || defined(HAVE_FORKPTY) */
 211
 212
 213 /* These are pulled from various places. It isn't obvious on what platforms
 214    they are necessary, nor what the exact prototype should look like (which
 215    is likely to vary between platforms!) If you find you need one of these
 216    declarations, please move them to a platform-specific block and include
 217    proper prototypes. */
 218 #if 0
 219
 220 /* From Modules/resource.c */
 221 extern int getrusage();
 222 extern int getpagesize();
 223
 224 /* From Python/sysmodule.c and Modules/posixmodule.c */
 225 extern int fclose(FILE *);
 226
 227 /* From Modules/posixmodule.c */
 228 extern int fdatasync(int);
 229 /* XXX These are supposedly for SunOS4.1.3 but "shouldn't hurt elsewhere" */
 230 extern int rename(const char *, const char *);
 231 extern int pclose(FILE *);
 232 extern int lstat(const char *, struct stat *);
 233 extern int symlink(const char *, const char *);
 234 extern int fsync(int fd);
 235
 236 #endif /* 0 */
 237
 238
 239 /************************
 240  * WRAPPER FOR <math.h> *
 241  ************************/
 242
 243 /* On the 68K Mac, when using CFM (Code Fragment Manager),
 244    <math.h> requires special treatment -- we need to surround it with
 245    #pragma lib_export off / on...
 246    This is because MathLib.o is a static library, and exporting its
 247    symbols doesn't quite work...
 248    XXX Not sure now...  Seems to be something else going on as well... */
 249
 250 #ifndef HAVE_HYPOT
 251 extern double hypot(double, double);
 252 #ifdef MWERKS_BEFORE_PRO4
 253 #define hypot we_dont_want_faulty_hypot_decl
 254 #endif
 255 #endif
 256
 257 #ifndef HAVE_HYPOT
 258 #ifdef __MWERKS__
 259 #undef hypot
 260 #endif
 261 #endif
 262
 263 #if defined(USE_MSL) && defined(__MC68K__)
 264 /* CodeWarrior MSL 2.1.1 has weird define overrides that don't work
 265 ** when you take the address of math functions. If I interpret the
 266 ** ANSI C standard correctly this is illegal, but I haven't been able
 267 ** to convince the MetroWerks folks of this...
 268 */
 269 #undef acos
 270 #undef asin
 271 #undef atan
 272 #undef atan2
 273 #undef ceil
 274 #undef cos
 275 #undef cosh
 276 #undef exp
 277 #undef fabs
 278 #undef floor
 279 #undef fmod
 280 #undef log
 281 #undef log10
 282 #undef pow
 283 #undef sin
 284 #undef sinh
 285 #undef sqrt
 286 #undef tan
 287 #undef tanh
 288 #define acos acosd
 289 #define asin asind
 290 #define atan atand
 291 #define atan2 atan2d
 292 #define ceil ceild
 293 #define cos cosd
 294 #define cosh coshd
 295 #define exp expd
 296 #define fabs fabsd
 297 #define floor floord
 298 #define fmod fmodd
 299 #define log logd
 300 #define log10 log10d
 301 #define pow powd
 302 #define sin sind
 303 #define sinh sinhd
 304 #define sqrt sqrtd
 305 #define tan tand
 306 #define tanh tanhd
 307 #endif
 308
 309
 310 /************************************
 311  * MALLOC COMPATIBILITY FOR pymem.h *
 312  ************************************/
 313
 314 #ifndef DL_IMPORT       /* declarations for DLL import */
 315 #define DL_IMPORT(RTYPE) RTYPE
 316 #endif
 317
 318 #ifndef NULL
 319 #define NULL ((void *)0)
 320 #endif
 321
 322 #ifdef MALLOC_ZERO_RETURNS_NULL
 323 /* XXX Always allocate one extra byte, since some malloc's return NULL
 324    XXX for malloc(0) or realloc(p, 0). */
 325 #define _PyMem_EXTRA 1
 326 #else
 327 #define _PyMem_EXTRA 0
 328 #endif
 329
 330
 331 /* If the fd manipulation macros aren't defined,
 332    here is a set that should do the job */
 333
 334 #if 0 /* disabled and probably obsolete */
 335
 336 #ifndef FD_SETSIZE
 337 #define FD_SETSIZE      256
 338 #endif
 339
 340 #ifndef FD_SET
 341
 342 typedef long fd_mask;
 343
 344 #define NFDBITS (sizeof(fd_mask) * NBBY)        /* bits per mask */
 345 #ifndef howmany
 346 #define howmany(x, y)   (((x)+((y)-1))/(y))
 347 #endif /* howmany */
 348
 349 typedef struct fd_set {
 350         fd_mask fds_bits[howmany(FD_SETSIZE, NFDBITS)];
 351 } fd_set;
 352
 353 #define FD_SET(n, p)    ((p)->fds_bits[(n)/NFDBITS] |= (1 << ((n) % NFDBITS)))
 354 #define FD_CLR(n, p)    ((p)->fds_bits[(n)/NFDBITS] &= ~(1 << ((n) % NFDBITS)))
 355 #define FD_ISSET(n, p)  ((p)->fds_bits[(n)/NFDBITS] & (1 << ((n) % NFDBITS)))
 356 #define FD_ZERO(p)      memset((char *)(p), '\0', sizeof(*(p)))
 357
 358 #endif /* FD_SET */
 359
 360 #endif /* fd manipulation macros */
 361
 362
 363 #ifdef __cplusplus
 364 }
 365 #endif
 366
 367 #endif /* Py_PYPORT_H */