Include/pyport.h

   1 #ifndef Py_PYPORT_H
   2 #define Py_PYPORT_H
   3
   4 #include "pyconfig.h" /* include for defines */
   5
   6 /* Some versions of HP-UX & Solaris need inttypes.h for int32_t,
   7    INT32_MAX, etc. */
   8 #ifdef HAVE_INTTYPES_H
   9 #include <inttypes.h>
  10 #endif
  11
  12 #ifdef HAVE_STDINT_H
  13 #include <stdint.h>
  14 #endif
  15
  16 /**************************************************************************
  17 Symbols and macros to supply platform-independent interfaces to basic
  18 C language & library operations whose spellings vary across platforms.
  19
  20 Please try to make documentation here as clear as possible:  by definition,
  21 the stuff here is trying to illuminate C's darkest corners.
  22
  23 Config #defines referenced here:
  24
  25 SIGNED_RIGHT_SHIFT_ZERO_FILLS
  26 Meaning:  To be defined iff i>>j does not extend the sign bit when i is a
  27           signed integral type and i < 0.
  28 Used in:  Py_ARITHMETIC_RIGHT_SHIFT
  29
  30 Py_DEBUG
  31 Meaning:  Extra checks compiled in for debug mode.
  32 Used in:  Py_SAFE_DOWNCAST
  33
  34 HAVE_UINTPTR_T
  35 Meaning:  The C9X type uintptr_t is supported by the compiler
  36 Used in:  Py_uintptr_t
  37
  38 HAVE_LONG_LONG
  39 Meaning:  The compiler supports the C type "long long"
  40 Used in:  PY_LONG_LONG
  41
  42 **************************************************************************/
  43
  44
  45 /* For backward compatibility only. Obsolete, do not use. */
  46 #ifdef HAVE_PROTOTYPES
  47 #define Py_PROTO(x) x
  48 #else
  49 #define Py_PROTO(x) ()
  50 #endif
  51 #ifndef Py_FPROTO
  52 #define Py_FPROTO(x) Py_PROTO(x)
  53 #endif
  54
  55 /* typedefs for some C9X-defined synonyms for integral types.
  56  *
  57  * The names in Python are exactly the same as the C9X names, except with a
  58  * Py_ prefix.  Until C9X is universally implemented, this is the only way
  59  * to ensure that Python gets reliable names that don't conflict with names
  60  * in non-Python code that are playing their own tricks to define the C9X
  61  * names.
  62  *
  63  * NOTE: don't go nuts here!  Python has no use for *most* of the C9X
  64  * integral synonyms.  Only define the ones we actually need.
  65  */
  66
  67 #ifdef HAVE_LONG_LONG
  68 #ifndef PY_LONG_LONG
  69 #define PY_LONG_LONG long long
  70 #if defined(LLONG_MAX)
  71 /* If LLONG_MAX is defined in limits.h, use that. */
  72 #define PY_LLONG_MIN LLONG_MIN
  73 #define PY_LLONG_MAX LLONG_MAX
  74 #define PY_ULLONG_MAX ULLONG_MAX
  75 #elif defined(__LONG_LONG_MAX__)
  76 /* Otherwise, if GCC has a builtin define, use that. */
  77 #define PY_LLONG_MAX __LONG_LONG_MAX__
  78 #define PY_LLONG_MIN (-PY_LLONG_MAX-1)
  79 #define PY_ULLONG_MAX (__LONG_LONG_MAX__*2ULL + 1ULL)
  80 #else
  81 /* Otherwise, rely on two's complement. */
  82 #define PY_ULLONG_MAX (~0ULL)
  83 #define PY_LLONG_MAX  ((long long)(PY_ULLONG_MAX>>1))
  84 #define PY_LLONG_MIN (-PY_LLONG_MAX-1)
  85 #endif /* LLONG_MAX */
  86 #endif
  87 #endif /* HAVE_LONG_LONG */
  88
  89 /* a build with 30-bit digits for Python long integers needs an exact-width
  90  * 32-bit unsigned integer type to store those digits.  (We could just use
  91  * type 'unsigned long', but that would be wasteful on a system where longs
  92  * are 64-bits.)  On Unix systems, the autoconf macro AC_TYPE_UINT32_T defines
  93  * uint32_t to be such a type unless stdint.h or inttypes.h defines uint32_t.
  94  * However, it doesn't set HAVE_UINT32_T, so we do that here.
  95  */
  96 #if (defined UINT32_MAX || defined uint32_t)
  97 #ifndef PY_UINT32_T
  98 #define HAVE_UINT32_T 1
  99 #define PY_UINT32_T uint32_t
 100 #endif
 101 #endif
 102
 103 /* Macros for a 64-bit unsigned integer type; used for type 'twodigits' in the
 104  * long integer implementation, when 30-bit digits are enabled.
 105  */
 106 #if (defined UINT64_MAX || defined uint64_t)
 107 #ifndef PY_UINT64_T
 108 #define HAVE_UINT64_T 1
 109 #define PY_UINT64_T uint64_t
 110 #endif
 111 #endif
 112
 113 /* Signed variants of the above */
 114 #if (defined INT32_MAX || defined int32_t)
 115 #ifndef PY_INT32_T
 116 #define HAVE_INT32_T 1
 117 #define PY_INT32_T int32_t
 118 #endif
 119 #endif
 120 #if (defined INT64_MAX || defined int64_t)
 121 #ifndef PY_INT64_T
 122 #define HAVE_INT64_T 1
 123 #define PY_INT64_T int64_t
 124 #endif
 125 #endif
 126
 127 /* If PYLONG_BITS_IN_DIGIT is not defined then we'll use 30-bit digits if all
 128    the necessary integer types are available, and we're on a 64-bit platform
 129    (as determined by SIZEOF_VOID_P); otherwise we use 15-bit digits. */
 130
 131 #ifndef PYLONG_BITS_IN_DIGIT
 132 #if (defined HAVE_UINT64_T && defined HAVE_INT64_T && \
 133      defined HAVE_UINT32_T && defined HAVE_INT32_T && SIZEOF_VOID_P >= 8)
 134 #define PYLONG_BITS_IN_DIGIT 30
 135 #else
 136 #define PYLONG_BITS_IN_DIGIT 15
 137 #endif
 138 #endif
 139
 140 /* uintptr_t is the C9X name for an unsigned integral type such that a
 141  * legitimate void* can be cast to uintptr_t and then back to void* again
 142  * without loss of information.  Similarly for intptr_t, wrt a signed
 143  * integral type.
 144  */
 145 #ifdef HAVE_UINTPTR_T
 146 typedef uintptr_t       Py_uintptr_t;
 147 typedef intptr_t        Py_intptr_t;
 148
 149 #elif SIZEOF_VOID_P <= SIZEOF_INT
 150 typedef unsigned int    Py_uintptr_t;
 151 typedef int             Py_intptr_t;
 152
 153 #elif SIZEOF_VOID_P <= SIZEOF_LONG
 154 typedef unsigned long   Py_uintptr_t;
 155 typedef long            Py_intptr_t;
 156
 157 #elif defined(HAVE_LONG_LONG) && (SIZEOF_VOID_P <= SIZEOF_LONG_LONG)
 158 typedef unsigned PY_LONG_LONG   Py_uintptr_t;
 159 typedef PY_LONG_LONG            Py_intptr_t;
 160
 161 #else
 162 #   error "Python needs a typedef for Py_uintptr_t in pyport.h."
 163 #endif /* HAVE_UINTPTR_T */
 164
 165 /* Py_ssize_t is a signed integral type such that sizeof(Py_ssize_t) ==
 166  * sizeof(size_t).  C99 doesn't define such a thing directly (size_t is an
 167  * unsigned integral type).  See PEP 353 for details.
 168  */
 169 #ifdef HAVE_SSIZE_T
 170 typedef ssize_t         Py_ssize_t;
 171 #elif SIZEOF_VOID_P == SIZEOF_SIZE_T
 172 typedef Py_intptr_t     Py_ssize_t;
 173 #else
 174 #   error "Python needs a typedef for Py_ssize_t in pyport.h."
 175 #endif
 176
 177 /* Largest possible value of size_t.
 178    SIZE_MAX is part of C99, so it might be defined on some
 179    platforms. If it is not defined, (size_t)-1 is a portable
 180    definition for C89, due to the way signed->unsigned
 181    conversion is defined. */
 182 #ifdef SIZE_MAX
 183 #define PY_SIZE_MAX SIZE_MAX
 184 #else
 185 #define PY_SIZE_MAX ((size_t)-1)
 186 #endif
 187
 188 /* Largest positive value of type Py_ssize_t. */
 189 #define PY_SSIZE_T_MAX ((Py_ssize_t)(((size_t)-1)>>1))
 190 /* Smallest negative value of type Py_ssize_t. */
 191 #define PY_SSIZE_T_MIN (-PY_SSIZE_T_MAX-1)
 192
 193 #if SIZEOF_PID_T > SIZEOF_LONG
 194 #   error "Python doesn't support sizeof(pid_t) > sizeof(long)"
 195 #endif
 196
 197 /* PY_FORMAT_SIZE_T is a platform-specific modifier for use in a printf
 198  * format to convert an argument with the width of a size_t or Py_ssize_t.
 199  * C99 introduced "z" for this purpose, but not all platforms support that;
 200  * e.g., MS compilers use "I" instead.
 201  *
 202  * These "high level" Python format functions interpret "z" correctly on
 203  * all platforms (Python interprets the format string itself, and does whatever
 204  * the platform C requires to convert a size_t/Py_ssize_t argument):
 205  *
 206  *     PyString_FromFormat
 207  *     PyErr_Format
 208  *     PyString_FromFormatV
 209  *
 210  * Lower-level uses require that you interpolate the correct format modifier
 211  * yourself (e.g., calling printf, fprintf, sprintf, PyOS_snprintf); for
 212  * example,
 213  *
 214  *     Py_ssize_t index;
 215  *     fprintf(stderr, "index %" PY_FORMAT_SIZE_T "d sucks\n", index);
 216  *
 217  * That will expand to %ld, or %Id, or to something else correct for a
 218  * Py_ssize_t on the platform.
 219  */
 220 #ifndef PY_FORMAT_SIZE_T
 221 #   if SIZEOF_SIZE_T == SIZEOF_INT && !defined(__APPLE__)
 222 #       define PY_FORMAT_SIZE_T ""
 223 #   elif SIZEOF_SIZE_T == SIZEOF_LONG
 224 #       define PY_FORMAT_SIZE_T "l"
 225 #   elif defined(MS_WINDOWS)
 226 #       define PY_FORMAT_SIZE_T "I"
 227 #   else
 228 #       error "This platform's pyconfig.h needs to define PY_FORMAT_SIZE_T"
 229 #   endif
 230 #endif
 231
 232 /* Py_LOCAL can be used instead of static to get the fastest possible calling
 233  * convention for functions that are local to a given module.
 234  *
 235  * Py_LOCAL_INLINE does the same thing, and also explicitly requests inlining,
 236  * for platforms that support that.
 237  *
 238  * If PY_LOCAL_AGGRESSIVE is defined before python.h is included, more
 239  * "aggressive" inlining/optimizaion is enabled for the entire module.  This
 240  * may lead to code bloat, and may slow things down for those reasons.  It may
 241  * also lead to errors, if the code relies on pointer aliasing.  Use with
 242  * care.
 243  *
 244  * NOTE: You can only use this for functions that are entirely local to a
 245  * module; functions that are exported via method tables, callbacks, etc,
 246  * should keep using static.
 247  */
 248
 249 #undef USE_INLINE /* XXX - set via configure? */
 250
 251 #if defined(_MSC_VER)
 252 #if defined(PY_LOCAL_AGGRESSIVE)
 253 /* enable more aggressive optimization for visual studio */
 254 #pragma optimize("agtw", on)
 255 #endif
 256 /* ignore warnings if the compiler decides not to inline a function */
 257 #pragma warning(disable: 4710)
 258 /* fastest possible local call under MSVC */
 259 #define Py_LOCAL(type) static type __fastcall
 260 #define Py_LOCAL_INLINE(type) static __inline type __fastcall
 261 #elif defined(USE_INLINE)
 262 #define Py_LOCAL(type) static type
 263 #define Py_LOCAL_INLINE(type) static inline type
 264 #else
 265 #define Py_LOCAL(type) static type
 266 #define Py_LOCAL_INLINE(type) static type
 267 #endif
 268
 269 /* Py_MEMCPY can be used instead of memcpy in cases where the copied blocks
 270  * are often very short.  While most platforms have highly optimized code for
 271  * large transfers, the setup costs for memcpy are often quite high.  MEMCPY
 272  * solves this by doing short copies "in line".
 273  */
 274
 275 #if defined(_MSC_VER)
 276 #define Py_MEMCPY(target, source, length) do {                          \
 277                 size_t i_, n_ = (length);                               \
 278                 char *t_ = (void*) (target);                            \
 279                 const char *s_ = (void*) (source);                      \
 280                 if (n_ >= 16)                                           \
 281                         memcpy(t_, s_, n_);                             \
 282                 else                                                    \
 283                         for (i_ = 0; i_ < n_; i_++)                     \
 284                                 t_[i_] = s_[i_];                        \
 285         } while (0)
 286 #else
 287 #define Py_MEMCPY memcpy
 288 #endif
 289
 290 #include <stdlib.h>
 291
 292 #include <math.h> /* Moved here from the math section, before extern "C" */
 293
 294 /********************************************
 295  * WRAPPER FOR <time.h> and/or <sys/time.h> *
 296  ********************************************/
 297
 298 #ifdef TIME_WITH_SYS_TIME
 299 #include <sys/time.h>
 300 #include <time.h>
 301 #else /* !TIME_WITH_SYS_TIME */
 302 #ifdef HAVE_SYS_TIME_H
 303 #include <sys/time.h>
 304 #else /* !HAVE_SYS_TIME_H */
 305 #include <time.h>
 306 #endif /* !HAVE_SYS_TIME_H */
 307 #endif /* !TIME_WITH_SYS_TIME */
 308
 309
 310 /******************************
 311  * WRAPPER FOR <sys/select.h> *
 312  ******************************/
 313
 314 /* NB caller must include <sys/types.h> */
 315
 316 #ifdef HAVE_SYS_SELECT_H
 317
 318 #include <sys/select.h>
 319
 320 #endif /* !HAVE_SYS_SELECT_H */
 321
 322 /*******************************
 323  * stat() and fstat() fiddling *
 324  *******************************/
 325
 326 /* We expect that stat and fstat exist on most systems.
 327  *  It's confirmed on Unix, Mac and Windows.
 328  *  If you don't have them, add
 329  *      #define DONT_HAVE_STAT
 330  * and/or
 331  *      #define DONT_HAVE_FSTAT
 332  * to your pyconfig.h. Python code beyond this should check HAVE_STAT and
 333  * HAVE_FSTAT instead.
 334  * Also
 335  *      #define HAVE_SYS_STAT_H
 336  * if <sys/stat.h> exists on your platform, and
 337  *      #define HAVE_STAT_H
 338  * if <stat.h> does.
 339  */
 340 #ifndef DONT_HAVE_STAT
 341 #define HAVE_STAT
 342 #endif
 343
 344 #ifndef DONT_HAVE_FSTAT
 345 #define HAVE_FSTAT
 346 #endif
 347
 348 #ifdef RISCOS
 349 #include <sys/types.h>
 350 #include "unixstuff.h"
 351 #endif
 352
 353 #ifdef HAVE_SYS_STAT_H
 354 #if defined(PYOS_OS2) && defined(PYCC_GCC)
 355 #include <sys/types.h>
 356 #endif
 357 #include <sys/stat.h>
 358 #elif defined(HAVE_STAT_H)
 359 #include <stat.h>
 360 #endif
 361
 362 #if defined(PYCC_VACPP)
 363 /* VisualAge C/C++ Failed to Define MountType Field in sys/stat.h */
 364 #define S_IFMT (S_IFDIR|S_IFCHR|S_IFREG)
 365 #endif
 366
 367 #ifndef S_ISREG
 368 #define S_ISREG(x) (((x) & S_IFMT) == S_IFREG)
 369 #endif
 370
 371 #ifndef S_ISDIR
 372 #define S_ISDIR(x) (((x) & S_IFMT) == S_IFDIR)
 373 #endif
 374
 375
 376 #ifdef __cplusplus
 377 /* Move this down here since some C++ #include's don't like to be included
 378    inside an extern "C" */
 379 extern "C" {
 380 #endif
 381
 382
 383 /* Py_ARITHMETIC_RIGHT_SHIFT
 384  * C doesn't define whether a right-shift of a signed integer sign-extends
 385  * or zero-fills.  Here a macro to force sign extension:
 386  * Py_ARITHMETIC_RIGHT_SHIFT(TYPE, I, J)
 387  *    Return I >> J, forcing sign extension.  Arithmetically, return the
 388  *    floor of I/2**J.
 389  * Requirements:
 390  *    I should have signed integer type.  In the terminology of C99, this can
 391  *    be either one of the five standard signed integer types (signed char,
 392  *    short, int, long, long long) or an extended signed integer type.
 393  *    J is an integer >= 0 and strictly less than the number of bits in the
 394  *    type of I (because C doesn't define what happens for J outside that
 395  *    range either).
 396  *    TYPE used to specify the type of I, but is now ignored.  It's been left
 397  *    in for backwards compatibility with versions <= 2.6 or 3.0.
 398  * Caution:
 399  *    I may be evaluated more than once.
 400  */
 401 #ifdef SIGNED_RIGHT_SHIFT_ZERO_FILLS
 402 #define Py_ARITHMETIC_RIGHT_SHIFT(TYPE, I, J) \
 403         ((I) < 0 ? -1-((-1-(I)) >> (J)) : (I) >> (J))
 404 #else
 405 #define Py_ARITHMETIC_RIGHT_SHIFT(TYPE, I, J) ((I) >> (J))
 406 #endif
 407
 408 /* Py_FORCE_EXPANSION(X)
 409  * "Simply" returns its argument.  However, macro expansions within the
 410  * argument are evaluated.  This unfortunate trickery is needed to get
 411  * token-pasting to work as desired in some cases.
 412  */
 413 #define Py_FORCE_EXPANSION(X) X
 414
 415 /* Py_SAFE_DOWNCAST(VALUE, WIDE, NARROW)
 416  * Cast VALUE to type NARROW from type WIDE.  In Py_DEBUG mode, this
 417  * assert-fails if any information is lost.
 418  * Caution:
 419  *    VALUE may be evaluated more than once.
 420  */
 421 #ifdef Py_DEBUG
 422 #define Py_SAFE_DOWNCAST(VALUE, WIDE, NARROW) \
 423         (assert((WIDE)(NARROW)(VALUE) == (VALUE)), (NARROW)(VALUE))
 424 #else
 425 #define Py_SAFE_DOWNCAST(VALUE, WIDE, NARROW) (NARROW)(VALUE)
 426 #endif
 427
 428 /* Py_SET_ERRNO_ON_MATH_ERROR(x)
 429  * If a libm function did not set errno, but it looks like the result
 430  * overflowed or not-a-number, set errno to ERANGE or EDOM.  Set errno
 431  * to 0 before calling a libm function, and invoke this macro after,
 432  * passing the function result.
 433  * Caution:
 434  *    This isn't reliable.  See Py_OVERFLOWED comments.
 435  *    X is evaluated more than once.
 436  */
 437 #if defined(__FreeBSD__) || defined(__OpenBSD__) || (defined(__hpux) && defined(__ia64))
 438 #define _Py_SET_EDOM_FOR_NAN(X) if (isnan(X)) errno = EDOM;
 439 #else
 440 #define _Py_SET_EDOM_FOR_NAN(X) ;
 441 #endif
 442 #define Py_SET_ERRNO_ON_MATH_ERROR(X) \
 443         do { \
 444                 if (errno == 0) { \
 445                         if ((X) == Py_HUGE_VAL || (X) == -Py_HUGE_VAL) \
 446                                 errno = ERANGE; \
 447                         else _Py_SET_EDOM_FOR_NAN(X) \
 448                 } \
 449         } while(0)
 450
 451 /* Py_SET_ERANGE_ON_OVERFLOW(x)
 452  * An alias of Py_SET_ERRNO_ON_MATH_ERROR for backward-compatibility.
 453  */
 454 #define Py_SET_ERANGE_IF_OVERFLOW(X) Py_SET_ERRNO_ON_MATH_ERROR(X)
 455
 456 /* Py_ADJUST_ERANGE1(x)
 457  * Py_ADJUST_ERANGE2(x, y)
 458  * Set errno to 0 before calling a libm function, and invoke one of these
 459  * macros after, passing the function result(s) (Py_ADJUST_ERANGE2 is useful
 460  * for functions returning complex results).  This makes two kinds of
 461  * adjustments to errno:  (A) If it looks like the platform libm set
 462  * errno=ERANGE due to underflow, clear errno. (B) If it looks like the
 463  * platform libm overflowed but didn't set errno, force errno to ERANGE.  In
 464  * effect, we're trying to force a useful implementation of C89 errno
 465  * behavior.
 466  * Caution:
 467  *    This isn't reliable.  See Py_OVERFLOWED comments.
 468  *    X and Y may be evaluated more than once.
 469  */
 470 #define Py_ADJUST_ERANGE1(X)                                            \
 471         do {                                                            \
 472                 if (errno == 0) {                                       \
 473                         if ((X) == Py_HUGE_VAL || (X) == -Py_HUGE_VAL)  \
 474                                 errno = ERANGE;                         \
 475                 }                                                       \
 476                 else if (errno == ERANGE && (X) == 0.0)                 \
 477                         errno = 0;                                      \
 478         } while(0)
 479
 480 #define Py_ADJUST_ERANGE2(X, Y)                                         \
 481         do {                                                            \
 482                 if ((X) == Py_HUGE_VAL || (X) == -Py_HUGE_VAL ||        \
 483                     (Y) == Py_HUGE_VAL || (Y) == -Py_HUGE_VAL) {        \
 484                                 if (errno == 0)                         \
 485                                         errno = ERANGE;                 \
 486                 }                                                       \
 487                 else if (errno == ERANGE)                               \
 488                         errno = 0;                                      \
 489         } while(0)
 490
 491 /*  The functions _Py_dg_strtod and _Py_dg_dtoa in Python/dtoa.c (which are
 492  *  required to support the short float repr introduced in Python 3.1) require
 493  *  that the floating-point unit that's being used for arithmetic operations
 494  *  on C doubles is set to use 53-bit precision.  It also requires that the
 495  *  FPU rounding mode is round-half-to-even, but that's less often an issue.
 496  *
 497  *  If your FPU isn't already set to 53-bit precision/round-half-to-even, and
 498  *  you want to make use of _Py_dg_strtod and _Py_dg_dtoa, then you should
 499  *
 500  *     #define HAVE_PY_SET_53BIT_PRECISION 1
 501  *
 502  *  and also give appropriate definitions for the following three macros:
 503  *
 504  *    _PY_SET_53BIT_PRECISION_START : store original FPU settings, and
 505  *        set FPU to 53-bit precision/round-half-to-even
 506  *    _PY_SET_53BIT_PRECISION_END : restore original FPU settings
 507  *    _PY_SET_53BIT_PRECISION_HEADER : any variable declarations needed to
 508  *        use the two macros above.
 509  *
 510  * The macros are designed to be used within a single C function: see
 511  * Python/pystrtod.c for an example of their use.
 512  */
 513
 514 /* get and set x87 control word for gcc/x86 */
 515 #ifdef HAVE_GCC_ASM_FOR_X87
 516 #define HAVE_PY_SET_53BIT_PRECISION 1
 517 /* _Py_get/set_387controlword functions are defined in Python/pymath.c */
 518 #define _Py_SET_53BIT_PRECISION_HEADER                          \
 519         unsigned short old_387controlword, new_387controlword
 520 #define _Py_SET_53BIT_PRECISION_START                                   \
 521         do {                                                            \
 522                 old_387controlword = _Py_get_387controlword();          \
 523                 new_387controlword = (old_387controlword & ~0x0f00) | 0x0200; \
 524                 if (new_387controlword != old_387controlword)           \
 525                         _Py_set_387controlword(new_387controlword);     \
 526         } while (0)
 527 #define _Py_SET_53BIT_PRECISION_END                             \
 528         if (new_387controlword != old_387controlword)           \
 529                 _Py_set_387controlword(old_387controlword)
 530 #endif
 531
 532 /* default definitions are empty */
 533 #ifndef HAVE_PY_SET_53BIT_PRECISION
 534 #define _Py_SET_53BIT_PRECISION_HEADER
 535 #define _Py_SET_53BIT_PRECISION_START
 536 #define _Py_SET_53BIT_PRECISION_END
 537 #endif
 538
 539 /* If we can't guarantee 53-bit precision, don't use the code
 540    in Python/dtoa.c, but fall back to standard code.  This
 541    means that repr of a float will be long (17 sig digits).
 542
 543    Realistically, there are two things that could go wrong:
 544
 545    (1) doubles aren't IEEE 754 doubles, or
 546    (2) we're on x86 with the rounding precision set to 64-bits
 547        (extended precision), and we don't know how to change
 548        the rounding precision.
 549  */
 550
 551 #if !defined(DOUBLE_IS_LITTLE_ENDIAN_IEEE754) && \
 552     !defined(DOUBLE_IS_BIG_ENDIAN_IEEE754) && \
 553     !defined(DOUBLE_IS_ARM_MIXED_ENDIAN_IEEE754)
 554 #define PY_NO_SHORT_FLOAT_REPR
 555 #endif
 556
 557 /* double rounding is symptomatic of use of extended precision on x86.  If
 558    we're seeing double rounding, and we don't have any mechanism available for
 559    changing the FPU rounding precision, then don't use Python/dtoa.c. */
 560 #if defined(X87_DOUBLE_ROUNDING) && !defined(HAVE_PY_SET_53BIT_PRECISION)
 561 #define PY_NO_SHORT_FLOAT_REPR
 562 #endif
 563
 564
 565 /* Py_DEPRECATED(version)
 566  * Declare a variable, type, or function deprecated.
 567  * Usage:
 568  *    extern int old_var Py_DEPRECATED(2.3);
 569  *    typedef int T1 Py_DEPRECATED(2.4);
 570  *    extern int x() Py_DEPRECATED(2.5);
 571  */
 572 #if defined(__GNUC__) && ((__GNUC__ >= 4) || \
 573                           (__GNUC__ == 3) && (__GNUC_MINOR__ >= 1))
 574 #define Py_DEPRECATED(VERSION_UNUSED) __attribute__((__deprecated__))
 575 #else
 576 #define Py_DEPRECATED(VERSION_UNUSED)
 577 #endif
 578
 579 /**************************************************************************
 580 Prototypes that are missing from the standard include files on some systems
 581 (and possibly only some versions of such systems.)
 582
 583 Please be conservative with adding new ones, document them and enclose them
 584 in platform-specific #ifdefs.
 585 **************************************************************************/
 586
 587 #ifdef SOLARIS
 588 /* Unchecked */
 589 extern int gethostname(char *, int);
 590 #endif
 591
 592 #ifdef __BEOS__
 593 /* Unchecked */
 594 /* It's in the libs, but not the headers... - [cjh] */
 595 int shutdown( int, int );
 596 #endif
 597
 598 #ifdef HAVE__GETPTY
 599 #include <sys/types.h>          /* we need to import mode_t */
 600 extern char * _getpty(int *, int, mode_t, int);
 601 #endif
 602
 603 /* On QNX 6, struct termio must be declared by including sys/termio.h
 604    if TCGETA, TCSETA, TCSETAW, or TCSETAF are used.  sys/termio.h must
 605    be included before termios.h or it will generate an error. */
 606 #ifdef HAVE_SYS_TERMIO_H
 607 #include <sys/termio.h>
 608 #endif
 609
 610 #if defined(HAVE_OPENPTY) || defined(HAVE_FORKPTY)
 611 #if !defined(HAVE_PTY_H) && !defined(HAVE_LIBUTIL_H)
 612 /* BSDI does not supply a prototype for the 'openpty' and 'forkpty'
 613    functions, even though they are included in libutil. */
 614 #include <termios.h>
 615 extern int openpty(int *, int *, char *, struct termios *, struct winsize *);
 616 extern pid_t forkpty(int *, char *, struct termios *, struct winsize *);
 617 #endif /* !defined(HAVE_PTY_H) && !defined(HAVE_LIBUTIL_H) */
 618 #endif /* defined(HAVE_OPENPTY) || defined(HAVE_FORKPTY) */
 619
 620
 621 /* These are pulled from various places. It isn't obvious on what platforms
 622    they are necessary, nor what the exact prototype should look like (which
 623    is likely to vary between platforms!) If you find you need one of these
 624    declarations, please move them to a platform-specific block and include
 625    proper prototypes. */
 626 #if 0
 627
 628 /* From Modules/resource.c */
 629 extern int getrusage();
 630 extern int getpagesize();
 631
 632 /* From Python/sysmodule.c and Modules/posixmodule.c */
 633 extern int fclose(FILE *);
 634
 635 /* From Modules/posixmodule.c */
 636 extern int fdatasync(int);
 637 #endif /* 0 */
 638
 639
 640 /* On 4.4BSD-descendants, ctype functions serves the whole range of
 641  * wchar_t character set rather than single byte code points only.
 642  * This characteristic can break some operations of string object
 643  * including str.upper() and str.split() on UTF-8 locales.  This
 644  * workaround was provided by Tim Robbins of FreeBSD project.
 645  */
 646
 647 #ifdef __FreeBSD__
 648 #include <osreldate.h>
 649 #if __FreeBSD_version > 500039
 650 #include <ctype.h>
 651 #include <wctype.h>
 652 #undef isalnum
 653 #define isalnum(c) iswalnum(btowc(c))
 654 #undef isalpha
 655 #define isalpha(c) iswalpha(btowc(c))
 656 #undef islower
 657 #define islower(c) iswlower(btowc(c))
 658 #undef isspace
 659 #define isspace(c) iswspace(btowc(c))
 660 #undef isupper
 661 #define isupper(c) iswupper(btowc(c))
 662 #undef tolower
 663 #define tolower(c) towlower(btowc(c))
 664 #undef toupper
 665 #define toupper(c) towupper(btowc(c))
 666 #endif
 667 #endif
 668
 669
 670 /* Declarations for symbol visibility.
 671
 672   PyAPI_FUNC(type): Declares a public Python API function and return type
 673   PyAPI_DATA(type): Declares public Python data and its type
 674   PyMODINIT_FUNC:   A Python module init function.  If these functions are
 675                     inside the Python core, they are private to the core.
 676                     If in an extension module, it may be declared with
 677                     external linkage depending on the platform.
 678
 679   As a number of platforms support/require "__declspec(dllimport/dllexport)",
 680   we support a HAVE_DECLSPEC_DLL macro to save duplication.
 681 */
 682
 683 /*
 684   All windows ports, except cygwin, are handled in PC/pyconfig.h.
 685
 686   BeOS and cygwin are the only other autoconf platform requiring special
 687   linkage handling and both of these use __declspec().
 688 */
 689 #if defined(__CYGWIN__) || defined(__BEOS__)
 690 #       define HAVE_DECLSPEC_DLL
 691 #endif
 692
 693 /* only get special linkage if built as shared or platform is Cygwin */
 694 #if defined(Py_ENABLE_SHARED) || defined(__CYGWIN__)
 695 #       if defined(HAVE_DECLSPEC_DLL)
 696 #               ifdef Py_BUILD_CORE
 697 #                       define PyAPI_FUNC(RTYPE) __declspec(dllexport) RTYPE
 698 #                       define PyAPI_DATA(RTYPE) extern __declspec(dllexport) RTYPE
 699                         /* module init functions inside the core need no external linkage */
 700                         /* except for Cygwin to handle embedding (FIXME: BeOS too?) */
 701 #                       if defined(__CYGWIN__)
 702 #                               define PyMODINIT_FUNC __declspec(dllexport) void
 703 #                       else /* __CYGWIN__ */
 704 #                               define PyMODINIT_FUNC void
 705 #                       endif /* __CYGWIN__ */
 706 #               else /* Py_BUILD_CORE */
 707                         /* Building an extension module, or an embedded situation */
 708                         /* public Python functions and data are imported */
 709                         /* Under Cygwin, auto-import functions to prevent compilation */
 710                         /* failures similar to http://python.org/doc/FAQ.html#3.24 */
 711 #                       if !defined(__CYGWIN__)
 712 #                               define PyAPI_FUNC(RTYPE) __declspec(dllimport) RTYPE
 713 #                       endif /* !__CYGWIN__ */
 714 #                       define PyAPI_DATA(RTYPE) extern __declspec(dllimport) RTYPE
 715                         /* module init functions outside the core must be exported */
 716 #                       if defined(__cplusplus)
 717 #                               define PyMODINIT_FUNC extern "C" __declspec(dllexport) void
 718 #                       else /* __cplusplus */
 719 #                               define PyMODINIT_FUNC __declspec(dllexport) void
 720 #                       endif /* __cplusplus */
 721 #               endif /* Py_BUILD_CORE */
 722 #       endif /* HAVE_DECLSPEC */
 723 #endif /* Py_ENABLE_SHARED */
 724
 725 /* If no external linkage macros defined by now, create defaults */
 726 #ifndef PyAPI_FUNC
 727 #       define PyAPI_FUNC(RTYPE) RTYPE
 728 #endif
 729 #ifndef PyAPI_DATA
 730 #       define PyAPI_DATA(RTYPE) extern RTYPE
 731 #endif
 732 #ifndef PyMODINIT_FUNC
 733 #       if defined(__cplusplus)
 734 #               define PyMODINIT_FUNC extern "C" void
 735 #       else /* __cplusplus */
 736 #               define PyMODINIT_FUNC void
 737 #       endif /* __cplusplus */
 738 #endif
 739
 740 /* Deprecated DL_IMPORT and DL_EXPORT macros */
 741 #if defined(Py_ENABLE_SHARED) && defined (HAVE_DECLSPEC_DLL)
 742 #       if defined(Py_BUILD_CORE)
 743 #               define DL_IMPORT(RTYPE) __declspec(dllexport) RTYPE
 744 #               define DL_EXPORT(RTYPE) __declspec(dllexport) RTYPE
 745 #       else
 746 #               define DL_IMPORT(RTYPE) __declspec(dllimport) RTYPE
 747 #               define DL_EXPORT(RTYPE) __declspec(dllexport) RTYPE
 748 #       endif
 749 #endif
 750 #ifndef DL_EXPORT
 751 #       define DL_EXPORT(RTYPE) RTYPE
 752 #endif
 753 #ifndef DL_IMPORT
 754 #       define DL_IMPORT(RTYPE) RTYPE
 755 #endif
 756 /* End of deprecated DL_* macros */
 757
 758 /* If the fd manipulation macros aren't defined,
 759    here is a set that should do the job */
 760
 761 #if 0 /* disabled and probably obsolete */
 762
 763 #ifndef FD_SETSIZE
 764 #define FD_SETSIZE      256
 765 #endif
 766
 767 #ifndef FD_SET
 768
 769 typedef long fd_mask;
 770
 771 #define NFDBITS (sizeof(fd_mask) * NBBY)        /* bits per mask */
 772 #ifndef howmany
 773 #define howmany(x, y)   (((x)+((y)-1))/(y))
 774 #endif /* howmany */
 775
 776 typedef struct fd_set {
 777         fd_mask fds_bits[howmany(FD_SETSIZE, NFDBITS)];
 778 } fd_set;
 779
 780 #define FD_SET(n, p)    ((p)->fds_bits[(n)/NFDBITS] |= (1 << ((n) % NFDBITS)))
 781 #define FD_CLR(n, p)    ((p)->fds_bits[(n)/NFDBITS] &= ~(1 << ((n) % NFDBITS)))
 782 #define FD_ISSET(n, p)  ((p)->fds_bits[(n)/NFDBITS] & (1 << ((n) % NFDBITS)))
 783 #define FD_ZERO(p)      memset((char *)(p), '\0', sizeof(*(p)))
 784
 785 #endif /* FD_SET */
 786
 787 #endif /* fd manipulation macros */
 788
 789
 790 /* limits.h constants that may be missing */
 791
 792 #ifndef INT_MAX
 793 #define INT_MAX 2147483647
 794 #endif
 795
 796 #ifndef LONG_MAX
 797 #if SIZEOF_LONG == 4
 798 #define LONG_MAX 0X7FFFFFFFL
 799 #elif SIZEOF_LONG == 8
 800 #define LONG_MAX 0X7FFFFFFFFFFFFFFFL
 801 #else
 802 #error "could not set LONG_MAX in pyport.h"
 803 #endif
 804 #endif
 805
 806 #ifndef LONG_MIN
 807 #define LONG_MIN (-LONG_MAX-1)
 808 #endif
 809
 810 #ifndef LONG_BIT
 811 #define LONG_BIT (8 * SIZEOF_LONG)
 812 #endif
 813
 814 #if LONG_BIT != 8 * SIZEOF_LONG
 815 /* 04-Oct-2000 LONG_BIT is apparently (mis)defined as 64 on some recent
 816  * 32-bit platforms using gcc.  We try to catch that here at compile-time
 817  * rather than waiting for integer multiplication to trigger bogus
 818  * overflows.
 819  */
 820 #error "LONG_BIT definition appears wrong for platform (bad gcc/glibc config?)."
 821 #endif
 822
 823 #ifdef __cplusplus
 824 }
 825 #endif
 826
 827 /*
 828  * Hide GCC attributes from compilers that don't support them.
 829  */
 830 #if (!defined(__GNUC__) || __GNUC__ < 2 || \
 831      (__GNUC__ == 2 && __GNUC_MINOR__ < 7) ) && \
 832     !defined(RISCOS)
 833 #define Py_GCC_ATTRIBUTE(x)
 834 #else
 835 #define Py_GCC_ATTRIBUTE(x) __attribute__(x)
 836 #endif
 837
 838 /*
 839  * Add PyArg_ParseTuple format where available.
 840  */
 841 #ifdef HAVE_ATTRIBUTE_FORMAT_PARSETUPLE
 842 #define Py_FORMAT_PARSETUPLE(func,p1,p2) __attribute__((format(func,p1,p2)))
 843 #else
 844 #define Py_FORMAT_PARSETUPLE(func,p1,p2)
 845 #endif
 846
 847 /*
 848  * Specify alignment on compilers that support it.
 849  */
 850 #if defined(__GNUC__) && __GNUC__ >= 3
 851 #define Py_ALIGNED(x) __attribute__((aligned(x)))
 852 #else
 853 #define Py_ALIGNED(x)
 854 #endif
 855
 856 /* Eliminate end-of-loop code not reached warnings from SunPro C
 857  * when using do{...}while(0) macros
 858  */
 859 #ifdef __SUNPRO_C
 860 #pragma error_messages (off,E_END_OF_LOOP_CODE_NOT_REACHED)
 861 #endif
 862
 863 /*
 864  * Older Microsoft compilers don't support the C99 long long literal suffixes,
 865  * so these will be defined in PC/pyconfig.h for those compilers.
 866  */
 867 #ifndef Py_LL
 868 #define Py_LL(x) x##LL
 869 #endif
 870
 871 #ifndef Py_ULL
 872 #define Py_ULL(x) Py_LL(x##U)
 873 #endif
 874
 875 #endif /* Py_PYPORT_H */