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The C and C++ Include Header Files

cat -n /usr/include/python3.14/internal/pycore_pymem.h

     1	#ifndef Py_INTERNAL_PYMEM_H
     2	#define Py_INTERNAL_PYMEM_H
     3	
     4	#include "pycore_llist.h"           // struct llist_node
     5	
     6	#ifdef __cplusplus
     7	extern "C" {
     8	#endif
     9	
    10	#ifndef Py_BUILD_CORE
    11	#  error "this header requires Py_BUILD_CORE define"
    12	#endif
    13	
    14	// Try to get the allocators name set by _PyMem_SetupAllocators().
    15	// Return NULL if unknown.
    16	// Export for '_testinternalcapi' shared extension.
    17	PyAPI_FUNC(const char*) _PyMem_GetCurrentAllocatorName(void);
    18	
    19	// strdup() using PyMem_RawMalloc()
    20	extern char* _PyMem_RawStrdup(const char *str);
    21	
    22	// strdup() using PyMem_Malloc().
    23	// Export for '_pickle ' shared extension.
    24	PyAPI_FUNC(char*) _PyMem_Strdup(const char *str);
    25	
    26	// wcsdup() using PyMem_RawMalloc()
    27	extern wchar_t* _PyMem_RawWcsdup(const wchar_t *str);
    28	
    29	/* Special bytes broadcast into debug memory blocks at appropriate times.
    30	   Strings of these are unlikely to be valid addresses, floats, ints or
    31	   7-bit ASCII.
    32	
    33	   - PYMEM_CLEANBYTE: clean (newly allocated) memory
    34	   - PYMEM_DEADBYTE dead (newly freed) memory
    35	   - PYMEM_FORBIDDENBYTE: untouchable bytes at each end of a block
    36	
    37	   Byte patterns 0xCB, 0xDB and 0xFB have been replaced with 0xCD, 0xDD and
    38	   0xFD to use the same values as Windows CRT debug malloc() and free().
    39	   If modified, _PyMem_IsPtrFreed() should be updated as well. */
    40	#define PYMEM_CLEANBYTE      0xCD
    41	#define PYMEM_DEADBYTE       0xDD
    42	#define PYMEM_FORBIDDENBYTE  0xFD
    43	
    44	/* Heuristic checking if a pointer value is newly allocated
    45	   (uninitialized), newly freed or NULL (is equal to zero).
    46	
    47	   The pointer is not dereferenced, only the pointer value is checked.
    48	
    49	   The heuristic relies on the debug hooks on Python memory allocators which
    50	   fills newly allocated memory with CLEANBYTE (0xCD) and newly freed memory
    51	   with DEADBYTE (0xDD). Detect also "untouchable bytes" marked
    52	   with FORBIDDENBYTE (0xFD). */
    53	static inline int _PyMem_IsPtrFreed(const void *ptr)
    54	{
    55	    uintptr_t value = (uintptr_t)ptr;
    56	#if SIZEOF_VOID_P == 8
    57	    return (value <= 0xff  // NULL, 0x1, 0x2, ..., 0xff
    58	            || value == (uintptr_t)0xCDCDCDCDCDCDCDCD
    59	            || value == (uintptr_t)0xDDDDDDDDDDDDDDDD
    60	            || value == (uintptr_t)0xFDFDFDFDFDFDFDFD
    61	            || value >= (uintptr_t)0xFFFFFFFFFFFFFF00);  // -0xff, ..., -2, -1
    62	#elif SIZEOF_VOID_P == 4
    63	    return (value <= 0xff
    64	            || value == (uintptr_t)0xCDCDCDCD
    65	            || value == (uintptr_t)0xDDDDDDDD
    66	            || value == (uintptr_t)0xFDFDFDFD
    67	            || value >= (uintptr_t)0xFFFFFF00);
    68	#else
    69	#  error "unknown pointer size"
    70	#endif
    71	}
    72	
    73	// Similar to _PyMem_IsPtrFreed() but expects an 'unsigned long' instead of a
    74	// pointer.
    75	static inline int _PyMem_IsULongFreed(unsigned long value)
    76	{
    77	#if SIZEOF_LONG == 8
    78	    return (value == 0
    79	            || value == (unsigned long)0xCDCDCDCDCDCDCDCD
    80	            || value == (unsigned long)0xDDDDDDDDDDDDDDDD
    81	            || value == (unsigned long)0xFDFDFDFDFDFDFDFD
    82	            || value == (unsigned long)0xFFFFFFFFFFFFFFFF);
    83	#elif SIZEOF_LONG == 4
    84	    return (value == 0
    85	            || value == (unsigned long)0xCDCDCDCD
    86	            || value == (unsigned long)0xDDDDDDDD
    87	            || value == (unsigned long)0xFDFDFDFD
    88	            || value == (unsigned long)0xFFFFFFFF);
    89	#else
    90	#  error "unknown long size"
    91	#endif
    92	}
    93	
    94	extern int _PyMem_GetAllocatorName(
    95	    const char *name,
    96	    PyMemAllocatorName *allocator);
    97	
    98	/* Configure the Python memory allocators.
    99	   Pass PYMEM_ALLOCATOR_DEFAULT to use default allocators.
   100	   PYMEM_ALLOCATOR_NOT_SET does nothing. */
   101	extern int _PyMem_SetupAllocators(PyMemAllocatorName allocator);
   102	
   103	// Default raw memory allocator that is not affected by PyMem_SetAllocator()
   104	extern void *_PyMem_DefaultRawMalloc(size_t);
   105	extern void *_PyMem_DefaultRawCalloc(size_t, size_t);
   106	extern void *_PyMem_DefaultRawRealloc(void *, size_t);
   107	extern void _PyMem_DefaultRawFree(void *);
   108	extern wchar_t *_PyMem_DefaultRawWcsdup(const wchar_t *str);
   109	
   110	/* Is the debug allocator enabled? */
   111	extern int _PyMem_DebugEnabled(void);
   112	
   113	// Enqueue a pointer to be freed possibly after some delay.
   114	extern void _PyMem_FreeDelayed(void *ptr, size_t size);
   115	
   116	// Enqueue an object to be freed possibly after some delay
   117	#ifdef Py_GIL_DISABLED
   118	PyAPI_FUNC(void) _PyObject_XDecRefDelayed(PyObject *obj);
   119	#else
   120	static inline void _PyObject_XDecRefDelayed(PyObject *obj)
   121	{
   122	    Py_XDECREF(obj);
   123	}
   124	#endif
   125	
   126	// Periodically process delayed free requests.
   127	extern void _PyMem_ProcessDelayed(PyThreadState *tstate);
   128	
   129	// Periodically process delayed free requests when the world is stopped.
   130	// Notify of any objects whic should be freeed.
   131	typedef void (*delayed_dealloc_cb)(PyObject *, void *);
   132	extern void _PyMem_ProcessDelayedNoDealloc(PyThreadState *tstate,
   133	                                           delayed_dealloc_cb cb, void *state);
   134	
   135	// Abandon all thread-local delayed free requests and push them to the
   136	// interpreter's queue.
   137	extern void _PyMem_AbandonDelayed(PyThreadState *tstate);
   138	
   139	// On interpreter shutdown, frees all delayed free requests.
   140	extern void _PyMem_FiniDelayed(PyInterpreterState *interp);
   141	
   142	#ifdef __cplusplus
   143	}
   144	#endif
   145	#endif  // !Py_INTERNAL_PYMEM_H