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The C and C++ Include Header Files

/usr/include/python3.10/internal/pycore_pymem.h


$ cat -n /usr/include/python3.10/internal/pycore_pymem.h

     1	#ifndef Py_INTERNAL_PYMEM_H
     2	#define Py_INTERNAL_PYMEM_H
     3	#ifdef __cplusplus
     4	extern "C" {
     5	#endif
     6	
     7	#ifndef Py_BUILD_CORE
     8	#  error "this header requires Py_BUILD_CORE define"
     9	#endif
    10	
    11	#include "pymem.h"      // PyMemAllocatorName
    12	
    13	
    14	/* Set the memory allocator of the specified domain to the default.
    15	   Save the old allocator into *old_alloc if it's non-NULL.
    16	   Return on success, or return -1 if the domain is unknown. */
    17	PyAPI_FUNC(int) _PyMem_SetDefaultAllocator(
    18	    PyMemAllocatorDomain domain,
    19	    PyMemAllocatorEx *old_alloc);
    20	
    21	/* Special bytes broadcast into debug memory blocks at appropriate times.
    22	   Strings of these are unlikely to be valid addresses, floats, ints or
    23	   7-bit ASCII.
    24	
    25	   - PYMEM_CLEANBYTE: clean (newly allocated) memory
    26	   - PYMEM_DEADBYTE dead (newly freed) memory
    27	   - PYMEM_FORBIDDENBYTE: untouchable bytes at each end of a block
    28	
    29	   Byte patterns 0xCB, 0xDB and 0xFB have been replaced with 0xCD, 0xDD and
    30	   0xFD to use the same values than Windows CRT debug malloc() and free().
    31	   If modified, _PyMem_IsPtrFreed() should be updated as well. */
    32	#define PYMEM_CLEANBYTE      0xCD
    33	#define PYMEM_DEADBYTE       0xDD
    34	#define PYMEM_FORBIDDENBYTE  0xFD
    35	
    36	/* Heuristic checking if a pointer value is newly allocated
    37	   (uninitialized), newly freed or NULL (is equal to zero).
    38	
    39	   The pointer is not dereferenced, only the pointer value is checked.
    40	
    41	   The heuristic relies on the debug hooks on Python memory allocators which
    42	   fills newly allocated memory with CLEANBYTE (0xCD) and newly freed memory
    43	   with DEADBYTE (0xDD). Detect also "untouchable bytes" marked
    44	   with FORBIDDENBYTE (0xFD). */
    45	static inline int _PyMem_IsPtrFreed(const void *ptr)
    46	{
    47	    uintptr_t value = (uintptr_t)ptr;
    48	#if SIZEOF_VOID_P == 8
    49	    return (value == 0
    50	            || value == (uintptr_t)0xCDCDCDCDCDCDCDCD
    51	            || value == (uintptr_t)0xDDDDDDDDDDDDDDDD
    52	            || value == (uintptr_t)0xFDFDFDFDFDFDFDFD);
    53	#elif SIZEOF_VOID_P == 4
    54	    return (value == 0
    55	            || value == (uintptr_t)0xCDCDCDCD
    56	            || value == (uintptr_t)0xDDDDDDDD
    57	            || value == (uintptr_t)0xFDFDFDFD);
    58	#else
    59	#  error "unknown pointer size"
    60	#endif
    61	}
    62	
    63	PyAPI_FUNC(int) _PyMem_GetAllocatorName(
    64	    const char *name,
    65	    PyMemAllocatorName *allocator);
    66	
    67	/* Configure the Python memory allocators.
    68	   Pass PYMEM_ALLOCATOR_DEFAULT to use default allocators.
    69	   PYMEM_ALLOCATOR_NOT_SET does nothing. */
    70	PyAPI_FUNC(int) _PyMem_SetupAllocators(PyMemAllocatorName allocator);
    71	
    72	struct _PyTraceMalloc_Config {
    73	    /* Module initialized?
    74	       Variable protected by the GIL */
    75	    enum {
    76	        TRACEMALLOC_NOT_INITIALIZED,
    77	        TRACEMALLOC_INITIALIZED,
    78	        TRACEMALLOC_FINALIZED
    79	    } initialized;
    80	
    81	    /* Is tracemalloc tracing memory allocations?
    82	       Variable protected by the GIL */
    83	    int tracing;
    84	
    85	    /* limit of the number of frames in a traceback, 1 by default.
    86	       Variable protected by the GIL. */
    87	    int max_nframe;
    88	};
    89	
    90	#define _PyTraceMalloc_Config_INIT \
    91	    {.initialized = TRACEMALLOC_NOT_INITIALIZED, \
    92	     .tracing = 0, \
    93	     .max_nframe = 1}
    94	
    95	PyAPI_DATA(struct _PyTraceMalloc_Config) _Py_tracemalloc_config;
    96	
    97	
    98	#ifdef __cplusplus
    99	}
   100	#endif
   101	#endif /* !Py_INTERNAL_PYMEM_H */