cpython/Include/pyport.h

610 lines
19 KiB
C

#ifndef Py_PYPORT_H
#define Py_PYPORT_H
#ifndef UCHAR_MAX
# error "<limits.h> header must define UCHAR_MAX"
#endif
#if UCHAR_MAX != 255
# error "Python's source code assumes C's unsigned char is an 8-bit type"
#endif
// Macro to use C++ static_cast<> in the Python C API.
#ifdef __cplusplus
# define _Py_STATIC_CAST(type, expr) static_cast<type>(expr)
#else
# define _Py_STATIC_CAST(type, expr) ((type)(expr))
#endif
// Macro to use the more powerful/dangerous C-style cast even in C++.
#define _Py_CAST(type, expr) ((type)(expr))
// Static inline functions should use _Py_NULL rather than using directly NULL
// to prevent C++ compiler warnings. On C23 and newer and on C++11 and newer,
// _Py_NULL is defined as nullptr.
#if (defined (__STDC_VERSION__) && __STDC_VERSION__ > 201710L) \
|| (defined(__cplusplus) && __cplusplus >= 201103)
# define _Py_NULL nullptr
#else
# define _Py_NULL NULL
#endif
/* Defines to build Python and its standard library:
*
* - Py_BUILD_CORE: Build Python core. Give access to Python internals, but
* should not be used by third-party modules.
* - Py_BUILD_CORE_BUILTIN: Build a Python stdlib module as a built-in module.
* - Py_BUILD_CORE_MODULE: Build a Python stdlib module as a dynamic library.
*
* Py_BUILD_CORE_BUILTIN and Py_BUILD_CORE_MODULE imply Py_BUILD_CORE.
*
* On Windows, Py_BUILD_CORE_MODULE exports "PyInit_xxx" symbol, whereas
* Py_BUILD_CORE_BUILTIN does not.
*/
#if defined(Py_BUILD_CORE_BUILTIN) && !defined(Py_BUILD_CORE)
# define Py_BUILD_CORE
#endif
#if defined(Py_BUILD_CORE_MODULE) && !defined(Py_BUILD_CORE)
# define Py_BUILD_CORE
#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
**************************************************************************/
/* 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.
*/
/* long long is required. Ensure HAVE_LONG_LONG is defined for compatibility. */
#ifndef HAVE_LONG_LONG
#define HAVE_LONG_LONG 1
#endif
#ifndef PY_LONG_LONG
#define PY_LONG_LONG long long
/* 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
#endif
#define PY_UINT32_T uint32_t
#define PY_UINT64_T uint64_t
/* Signed variants of the above */
#define PY_INT32_T int32_t
#define PY_INT64_T int64_t
/* PYLONG_BITS_IN_DIGIT describes the number of bits per "digit" (limb) in the
* PyLongObject implementation (longintrepr.h). It's currently either 30 or 15,
* defaulting to 30. The 15-bit digit option may be removed in the future.
*/
#ifndef PYLONG_BITS_IN_DIGIT
#define PYLONG_BITS_IN_DIGIT 30
#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.
*/
typedef uintptr_t Py_uintptr_t;
typedef intptr_t Py_intptr_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.
* PY_SSIZE_T_MAX is the largest positive value of type Py_ssize_t.
*/
#ifdef HAVE_PY_SSIZE_T
#elif HAVE_SSIZE_T
typedef ssize_t Py_ssize_t;
# define PY_SSIZE_T_MAX SSIZE_MAX
#elif SIZEOF_VOID_P == SIZEOF_SIZE_T
typedef Py_intptr_t Py_ssize_t;
# define PY_SSIZE_T_MAX INTPTR_MAX
#else
# error "Python needs a typedef for Py_ssize_t in pyport.h."
#endif
/* Smallest negative value of type Py_ssize_t. */
#define PY_SSIZE_T_MIN (-PY_SSIZE_T_MAX-1)
/* Py_hash_t is the same size as a pointer. */
#define SIZEOF_PY_HASH_T SIZEOF_SIZE_T
typedef Py_ssize_t Py_hash_t;
/* Py_uhash_t is the unsigned equivalent needed to calculate numeric hash. */
#define SIZEOF_PY_UHASH_T SIZEOF_SIZE_T
typedef size_t Py_uhash_t;
/* Now PY_SSIZE_T_CLEAN is mandatory. This is just for backward compatibility. */
typedef Py_ssize_t Py_ssize_clean_t;
/* Largest possible value of size_t. */
#define PY_SIZE_MAX SIZE_MAX
/* Macro kept for backward compatibility: use directly "z" in new code.
*
* PY_FORMAT_SIZE_T is a modifier for use in a printf format to convert an
* argument with the width of a size_t or Py_ssize_t: "z" (C99).
*/
#ifndef PY_FORMAT_SIZE_T
# define PY_FORMAT_SIZE_T "z"
#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.
*
* 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.
*/
#if defined(_MSC_VER)
/* 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
#else
# define Py_LOCAL(type) static type
# define Py_LOCAL_INLINE(type) static inline type
#endif
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 < 0x030b0000
# define Py_MEMCPY memcpy
#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(_Py_STATIC_CAST(WIDE, _Py_STATIC_CAST(NARROW, (VALUE))) == (VALUE)), \
_Py_STATIC_CAST(NARROW, (VALUE)))
#else
# define Py_SAFE_DOWNCAST(VALUE, WIDE, NARROW) _Py_STATIC_CAST(NARROW, (VALUE))
#endif
/* Py_DEPRECATED(version)
* Declare a variable, type, or function deprecated.
* The macro must be placed before the declaration.
* Usage:
* Py_DEPRECATED(3.3) extern int old_var;
* Py_DEPRECATED(3.4) typedef int T1;
* Py_DEPRECATED(3.8) PyAPI_FUNC(int) Py_OldFunction(void);
*/
#if defined(__GNUC__) \
&& ((__GNUC__ >= 4) || (__GNUC__ == 3) && (__GNUC_MINOR__ >= 1))
#define Py_DEPRECATED(VERSION_UNUSED) __attribute__((__deprecated__))
#elif defined(_MSC_VER)
#define Py_DEPRECATED(VERSION) __declspec(deprecated( \
"deprecated in " #VERSION))
#else
#define Py_DEPRECATED(VERSION_UNUSED)
#endif
// _Py_DEPRECATED_EXTERNALLY(version)
// Deprecated outside CPython core.
#ifdef Py_BUILD_CORE
#define _Py_DEPRECATED_EXTERNALLY(VERSION_UNUSED)
#else
#define _Py_DEPRECATED_EXTERNALLY(version) Py_DEPRECATED(version)
#endif
#if defined(__clang__)
#define _Py_COMP_DIAG_PUSH _Pragma("clang diagnostic push")
#define _Py_COMP_DIAG_IGNORE_DEPR_DECLS \
_Pragma("clang diagnostic ignored \"-Wdeprecated-declarations\"")
#define _Py_COMP_DIAG_POP _Pragma("clang diagnostic pop")
#elif defined(__GNUC__) \
&& ((__GNUC__ >= 5) || (__GNUC__ == 4) && (__GNUC_MINOR__ >= 6))
#define _Py_COMP_DIAG_PUSH _Pragma("GCC diagnostic push")
#define _Py_COMP_DIAG_IGNORE_DEPR_DECLS \
_Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"")
#define _Py_COMP_DIAG_POP _Pragma("GCC diagnostic pop")
#elif defined(_MSC_VER)
#define _Py_COMP_DIAG_PUSH __pragma(warning(push))
#define _Py_COMP_DIAG_IGNORE_DEPR_DECLS __pragma(warning(disable: 4996))
#define _Py_COMP_DIAG_POP __pragma(warning(pop))
#else
#define _Py_COMP_DIAG_PUSH
#define _Py_COMP_DIAG_IGNORE_DEPR_DECLS
#define _Py_COMP_DIAG_POP
#endif
/* _Py_HOT_FUNCTION
* The hot attribute on a function is used to inform the compiler that the
* function is a hot spot of the compiled program. The function is optimized
* more aggressively and on many target it is placed into special subsection of
* the text section so all hot functions appears close together improving
* locality.
*
* Usage:
* int _Py_HOT_FUNCTION x(void) { return 3; }
*
* Issue #28618: This attribute must not be abused, otherwise it can have a
* negative effect on performance. Only the functions were Python spend most of
* its time must use it. Use a profiler when running performance benchmark
* suite to find these functions.
*/
#if defined(__GNUC__) \
&& ((__GNUC__ >= 5) || (__GNUC__ == 4) && (__GNUC_MINOR__ >= 3))
#define _Py_HOT_FUNCTION __attribute__((hot))
#else
#define _Py_HOT_FUNCTION
#endif
// Ask the compiler to always inline a static inline function. The compiler can
// ignore it and decides to not inline the function.
//
// It can be used to inline performance critical static inline functions when
// building Python in debug mode with function inlining disabled. For example,
// MSC disables function inlining when building in debug mode.
//
// Marking blindly a static inline function with Py_ALWAYS_INLINE can result in
// worse performances (due to increased code size for example). The compiler is
// usually smarter than the developer for the cost/benefit analysis.
//
// If Python is built in debug mode (if the Py_DEBUG macro is defined), the
// Py_ALWAYS_INLINE macro does nothing.
//
// It must be specified before the function return type. Usage:
//
// static inline Py_ALWAYS_INLINE int random(void) { return 4; }
#if defined(Py_DEBUG)
// If Python is built in debug mode, usually compiler optimizations are
// disabled. In this case, Py_ALWAYS_INLINE can increase a lot the stack
// memory usage. For example, forcing inlining using gcc -O0 increases the
// stack usage from 6 KB to 15 KB per Python function call.
# define Py_ALWAYS_INLINE
#elif defined(__GNUC__) || defined(__clang__) || defined(__INTEL_COMPILER)
# define Py_ALWAYS_INLINE __attribute__((always_inline))
#elif defined(_MSC_VER)
# define Py_ALWAYS_INLINE __forceinline
#else
# define Py_ALWAYS_INLINE
#endif
// Py_NO_INLINE
// Disable inlining on a function. For example, it reduces the C stack
// consumption: useful on LTO+PGO builds which heavily inline code (see
// bpo-33720).
//
// Usage:
//
// Py_NO_INLINE static int random(void) { return 4; }
#if defined(__GNUC__) || defined(__clang__) || defined(__INTEL_COMPILER)
# define Py_NO_INLINE __attribute__ ((noinline))
#elif defined(_MSC_VER)
# define Py_NO_INLINE __declspec(noinline)
#else
# define Py_NO_INLINE
#endif
#include "exports.h"
#ifdef Py_LIMITED_API
// The internal C API must not be used with the limited C API: make sure
// that Py_BUILD_CORE macro is not defined in this case. These 3 macros are
// used by exports.h, so only undefine them afterwards.
# undef Py_BUILD_CORE
# undef Py_BUILD_CORE_BUILTIN
# undef Py_BUILD_CORE_MODULE
#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
/*
* 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
#ifndef Py_LL
#define Py_LL(x) x##LL
#endif
#ifndef Py_ULL
#define Py_ULL(x) Py_LL(x##U)
#endif
#define Py_VA_COPY va_copy
/*
* Convenient macros to deal with endianness of the platform. WORDS_BIGENDIAN is
* detected by configure and defined in pyconfig.h. The code in pyconfig.h
* also takes care of Apple's universal builds.
*/
#ifdef WORDS_BIGENDIAN
# define PY_BIG_ENDIAN 1
# define PY_LITTLE_ENDIAN 0
#else
# define PY_BIG_ENDIAN 0
# define PY_LITTLE_ENDIAN 1
#endif
#ifdef __ANDROID__
/* The Android langinfo.h header is not used. */
# undef HAVE_LANGINFO_H
# undef CODESET
#endif
/* Maximum value of the Windows DWORD type */
#define PY_DWORD_MAX 4294967295U
/* This macro used to tell whether Python was built with multithreading
* enabled. Now multithreading is always enabled, but keep the macro
* for compatibility.
*/
#ifndef WITH_THREAD
# define WITH_THREAD
#endif
/* Some WebAssembly platforms do not provide a working pthread implementation.
* Thread support is stubbed and any attempt to create a new thread fails.
*/
#if (!defined(HAVE_PTHREAD_STUBS) && \
(!defined(__EMSCRIPTEN__) || defined(__EMSCRIPTEN_PTHREADS__)))
# define Py_CAN_START_THREADS 1
#endif
#ifdef WITH_THREAD
# ifdef Py_BUILD_CORE
# ifdef HAVE_THREAD_LOCAL
# error "HAVE_THREAD_LOCAL is already defined"
# endif
# define HAVE_THREAD_LOCAL 1
# ifdef thread_local
# define _Py_thread_local thread_local
# elif __STDC_VERSION__ >= 201112L && !defined(__STDC_NO_THREADS__)
# define _Py_thread_local _Thread_local
# elif defined(_MSC_VER) /* AKA NT_THREADS */
# define _Py_thread_local __declspec(thread)
# elif defined(__GNUC__) /* includes clang */
# define _Py_thread_local __thread
# else
// fall back to the PyThread_tss_*() API, or ignore.
# undef HAVE_THREAD_LOCAL
# endif
# endif
#endif
#if defined(__ANDROID__) || defined(__VXWORKS__)
// Use UTF-8 as the locale encoding, ignore the LC_CTYPE locale.
// See _Py_GetLocaleEncoding(), PyUnicode_DecodeLocale()
// and PyUnicode_EncodeLocale().
# define _Py_FORCE_UTF8_LOCALE
#endif
#if defined(_Py_FORCE_UTF8_LOCALE) || defined(__APPLE__)
// Use UTF-8 as the filesystem encoding.
// See PyUnicode_DecodeFSDefaultAndSize(), PyUnicode_EncodeFSDefault(),
// Py_DecodeLocale() and Py_EncodeLocale().
# define _Py_FORCE_UTF8_FS_ENCODING
#endif
/* Mark a function which cannot return. Example:
PyAPI_FUNC(void) _Py_NO_RETURN PyThread_exit_thread(void);
XLC support is intentionally omitted due to bpo-40244 */
#ifndef _Py_NO_RETURN
#if defined(__clang__) || \
(defined(__GNUC__) && \
((__GNUC__ >= 3) || \
(__GNUC__ == 2) && (__GNUC_MINOR__ >= 5)))
# define _Py_NO_RETURN __attribute__((__noreturn__))
#elif defined(_MSC_VER)
# define _Py_NO_RETURN __declspec(noreturn)
#else
# define _Py_NO_RETURN
#endif
#endif
// Preprocessor check for a builtin preprocessor function. Always return 0
// if __has_builtin() macro is not defined.
//
// __has_builtin() is available on clang and GCC 10.
#ifdef __has_builtin
# define _Py__has_builtin(x) __has_builtin(x)
#else
# define _Py__has_builtin(x) 0
#endif
// _Py_TYPEOF(expr) gets the type of an expression.
//
// Example: _Py_TYPEOF(x) x_copy = (x);
//
// The macro is only defined if GCC or clang compiler is used.
#if defined(__GNUC__) || defined(__clang__)
# define _Py_TYPEOF(expr) __typeof__(expr)
#endif
/* A convenient way for code to know if sanitizers are enabled. */
#if defined(__has_feature)
# if __has_feature(memory_sanitizer)
# if !defined(_Py_MEMORY_SANITIZER)
# define _Py_MEMORY_SANITIZER
# endif
# endif
# if __has_feature(address_sanitizer)
# if !defined(_Py_ADDRESS_SANITIZER)
# define _Py_ADDRESS_SANITIZER
# endif
# endif
# if __has_feature(thread_sanitizer)
# if !defined(_Py_THREAD_SANITIZER)
# define _Py_THREAD_SANITIZER
# endif
# endif
#elif defined(__GNUC__)
# if defined(__SANITIZE_ADDRESS__)
# define _Py_ADDRESS_SANITIZER
# endif
# if defined(__SANITIZE_THREAD__)
# define _Py_THREAD_SANITIZER
# endif
#endif
/* AIX has __bool__ redefined in it's system header file. */
#if defined(_AIX) && defined(__bool__)
#undef __bool__
#endif
// Make sure we have maximum alignment, even if the current compiler
// does not support max_align_t. Note that:
// - Autoconf reports alignment of unknown types to 0.
// - 'long double' has maximum alignment on *most* platforms,
// looks like the best we can do for pre-C11 compilers.
// - The value is tested, see test_alignof_max_align_t
#if !defined(ALIGNOF_MAX_ALIGN_T) || ALIGNOF_MAX_ALIGN_T == 0
# undef ALIGNOF_MAX_ALIGN_T
# define ALIGNOF_MAX_ALIGN_T _Alignof(long double)
#endif
#ifndef PY_CXX_CONST
# ifdef __cplusplus
# define PY_CXX_CONST const
# else
# define PY_CXX_CONST
# endif
#endif
#if defined(__sgi) && !defined(_SGI_MP_SOURCE)
# define _SGI_MP_SOURCE
#endif
#endif /* Py_PYPORT_H */