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The C and C++ Include Header Files

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

     1	#ifndef Py_INTERNAL_OBJECT_STACK_H
     2	#define Py_INTERNAL_OBJECT_STACK_H
     3	
     4	#ifdef __cplusplus
     5	extern "C" {
     6	#endif
     7	
     8	#ifndef Py_BUILD_CORE
     9	#  error "this header requires Py_BUILD_CORE define"
    10	#endif
    11	
    12	// _PyObjectStack is a stack of Python objects implemented as a linked list of
    13	// fixed size buffers.
    14	
    15	// Chosen so that _PyObjectStackChunk is a power-of-two size.
    16	#define _Py_OBJECT_STACK_CHUNK_SIZE 254
    17	
    18	typedef struct _PyObjectStackChunk {
    19	    struct _PyObjectStackChunk *prev;
    20	    Py_ssize_t n;
    21	    PyObject *objs[_Py_OBJECT_STACK_CHUNK_SIZE];
    22	} _PyObjectStackChunk;
    23	
    24	typedef struct _PyObjectStack {
    25	    _PyObjectStackChunk *head;
    26	} _PyObjectStack;
    27	
    28	
    29	extern _PyObjectStackChunk *
    30	_PyObjectStackChunk_New(void);
    31	
    32	extern void
    33	_PyObjectStackChunk_Free(_PyObjectStackChunk *);
    34	
    35	// Push an item onto the stack. Return -1 on allocation failure, 0 on success.
    36	static inline int
    37	_PyObjectStack_Push(_PyObjectStack *stack, PyObject *obj)
    38	{
    39	    _PyObjectStackChunk *buf = stack->head;
    40	    if (buf == NULL || buf->n == _Py_OBJECT_STACK_CHUNK_SIZE) {
    41	        buf = _PyObjectStackChunk_New();
    42	        if (buf == NULL) {
    43	            return -1;
    44	        }
    45	        buf->prev = stack->head;
    46	        buf->n = 0;
    47	        stack->head = buf;
    48	    }
    49	
    50	    assert(buf->n >= 0 && buf->n < _Py_OBJECT_STACK_CHUNK_SIZE);
    51	    buf->objs[buf->n] = obj;
    52	    buf->n++;
    53	    return 0;
    54	}
    55	
    56	// Pop the top item from the stack.  Return NULL if the stack is empty.
    57	static inline PyObject *
    58	_PyObjectStack_Pop(_PyObjectStack *stack)
    59	{
    60	    _PyObjectStackChunk *buf = stack->head;
    61	    if (buf == NULL) {
    62	        return NULL;
    63	    }
    64	    assert(buf->n > 0 && buf->n <= _Py_OBJECT_STACK_CHUNK_SIZE);
    65	    buf->n--;
    66	    PyObject *obj = buf->objs[buf->n];
    67	    if (buf->n == 0) {
    68	        stack->head = buf->prev;
    69	        _PyObjectStackChunk_Free(buf);
    70	    }
    71	    return obj;
    72	}
    73	
    74	static inline Py_ssize_t
    75	_PyObjectStack_Size(_PyObjectStack *stack)
    76	{
    77	    Py_ssize_t size = 0;
    78	    for (_PyObjectStackChunk *buf = stack->head; buf != NULL; buf = buf->prev) {
    79	        size += buf->n;
    80	    }
    81	    return size;
    82	}
    83	
    84	// Merge src into dst, leaving src empty
    85	extern void
    86	_PyObjectStack_Merge(_PyObjectStack *dst, _PyObjectStack *src);
    87	
    88	// Remove all items from the stack
    89	extern void
    90	_PyObjectStack_Clear(_PyObjectStack *stack);
    91	
    92	#ifdef __cplusplus
    93	}
    94	#endif
    95	#endif  // !Py_INTERNAL_OBJECT_STACK_H