mirror of https://github.com/python/cpython
678 lines
23 KiB
C
678 lines
23 KiB
C
#ifndef Py_OBJECT_H
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#define Py_OBJECT_H
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#ifdef __cplusplus
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extern "C" {
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#endif
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/* Object and type object interface */
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/*
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Objects are structures allocated on the heap. Special rules apply to
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the use of objects to ensure they are properly garbage-collected.
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Objects are never allocated statically or on the stack; they must be
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accessed through special macros and functions only. (Type objects are
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exceptions to the first rule; the standard types are represented by
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statically initialized type objects.)
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An object has a 'reference count' that is increased or decreased when a
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pointer to the object is copied or deleted; when the reference count
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reaches zero there are no references to the object left and it can be
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removed from the heap.
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An object has a 'type' that determines what it represents and what kind
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of data it contains. An object's type is fixed when it is created.
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Types themselves are represented as objects; an object contains a
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pointer to the corresponding type object. The type itself has a type
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pointer pointing to the object representing the type 'type', which
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contains a pointer to itself!).
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Objects do not float around in memory; once allocated an object keeps
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the same size and address. Objects that must hold variable-size data
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can contain pointers to variable-size parts of the object. Not all
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objects of the same type have the same size; but the size cannot change
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after allocation. (These restrictions are made so a reference to an
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object can be simply a pointer -- moving an object would require
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updating all the pointers, and changing an object's size would require
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moving it if there was another object right next to it.)
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Objects are always accessed through pointers of the type 'PyObject *'.
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The type 'PyObject' is a structure that only contains the reference count
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and the type pointer. The actual memory allocated for an object
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contains other data that can only be accessed after casting the pointer
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to a pointer to a longer structure type. This longer type must start
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with the reference count and type fields; the macro PyObject_HEAD should be
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used for this (to accommodate for future changes). The implementation
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of a particular object type can cast the object pointer to the proper
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type and back.
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A standard interface exists for objects that contain an array of items
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whose size is determined when the object is allocated.
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*/
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#ifdef Py_DEBUG
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/* Turn on heavy reference debugging */
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#define Py_TRACE_REFS
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/* Turn on reference counting */
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#define Py_REF_DEBUG
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#endif /* Py_DEBUG */
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#ifdef Py_TRACE_REFS
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#define PyObject_HEAD \
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struct _object *_ob_next, *_ob_prev; \
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int ob_refcnt; \
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struct _typeobject *ob_type;
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#define PyObject_HEAD_INIT(type) 0, 0, 1, type,
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#else /* !Py_TRACE_REFS */
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#define PyObject_HEAD \
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int ob_refcnt; \
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struct _typeobject *ob_type;
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#define PyObject_HEAD_INIT(type) 1, type,
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#endif /* !Py_TRACE_REFS */
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#define PyObject_VAR_HEAD \
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PyObject_HEAD \
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int ob_size; /* Number of items in variable part */
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typedef struct _object {
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PyObject_HEAD
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} PyObject;
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typedef struct {
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PyObject_VAR_HEAD
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} PyVarObject;
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/*
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Type objects contain a string containing the type name (to help somewhat
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in debugging), the allocation parameters (see newobj() and newvarobj()),
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and methods for accessing objects of the type. Methods are optional,a
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nil pointer meaning that particular kind of access is not available for
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this type. The Py_DECREF() macro uses the tp_dealloc method without
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checking for a nil pointer; it should always be implemented except if
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the implementation can guarantee that the reference count will never
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reach zero (e.g., for type objects).
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NB: the methods for certain type groups are now contained in separate
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method blocks.
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*/
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typedef PyObject * (*unaryfunc)(PyObject *);
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typedef PyObject * (*binaryfunc)(PyObject *, PyObject *);
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typedef PyObject * (*ternaryfunc)(PyObject *, PyObject *, PyObject *);
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typedef int (*inquiry)(PyObject *);
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typedef int (*coercion)(PyObject **, PyObject **);
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typedef PyObject *(*intargfunc)(PyObject *, int);
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typedef PyObject *(*intintargfunc)(PyObject *, int, int);
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typedef int(*intobjargproc)(PyObject *, int, PyObject *);
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typedef int(*intintobjargproc)(PyObject *, int, int, PyObject *);
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typedef int(*objobjargproc)(PyObject *, PyObject *, PyObject *);
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typedef int (*getreadbufferproc)(PyObject *, int, void **);
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typedef int (*getwritebufferproc)(PyObject *, int, void **);
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typedef int (*getsegcountproc)(PyObject *, int *);
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typedef int (*getcharbufferproc)(PyObject *, int, const char **);
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typedef int (*objobjproc)(PyObject *, PyObject *);
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typedef int (*visitproc)(PyObject *, void *);
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typedef int (*traverseproc)(PyObject *, visitproc, void *);
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typedef struct {
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/* For numbers without flag bit Py_TPFLAGS_CHECKTYPES set, all
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arguments are guaranteed to be of the object's type (modulo
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coercion hacks that is -- i.e. if the type's coercion function
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returns other types, then these are allowed as well). Numbers that
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have the Py_TPFLAGS_CHECKTYPES flag bit set should check *both*
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arguments for proper type and implement the necessary conversions
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in the slot functions themselves. */
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binaryfunc nb_add;
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binaryfunc nb_subtract;
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binaryfunc nb_multiply;
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binaryfunc nb_divide;
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binaryfunc nb_remainder;
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binaryfunc nb_divmod;
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ternaryfunc nb_power;
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unaryfunc nb_negative;
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unaryfunc nb_positive;
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unaryfunc nb_absolute;
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inquiry nb_nonzero;
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unaryfunc nb_invert;
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binaryfunc nb_lshift;
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binaryfunc nb_rshift;
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binaryfunc nb_and;
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binaryfunc nb_xor;
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binaryfunc nb_or;
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coercion nb_coerce;
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unaryfunc nb_int;
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unaryfunc nb_long;
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unaryfunc nb_float;
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unaryfunc nb_oct;
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unaryfunc nb_hex;
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binaryfunc nb_inplace_add;
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binaryfunc nb_inplace_subtract;
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binaryfunc nb_inplace_multiply;
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binaryfunc nb_inplace_divide;
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binaryfunc nb_inplace_remainder;
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ternaryfunc nb_inplace_power;
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binaryfunc nb_inplace_lshift;
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binaryfunc nb_inplace_rshift;
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binaryfunc nb_inplace_and;
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binaryfunc nb_inplace_xor;
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binaryfunc nb_inplace_or;
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} PyNumberMethods;
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typedef struct {
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inquiry sq_length;
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binaryfunc sq_concat;
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intargfunc sq_repeat;
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intargfunc sq_item;
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intintargfunc sq_slice;
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intobjargproc sq_ass_item;
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intintobjargproc sq_ass_slice;
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objobjproc sq_contains;
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binaryfunc sq_inplace_concat;
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intargfunc sq_inplace_repeat;
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} PySequenceMethods;
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typedef struct {
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inquiry mp_length;
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binaryfunc mp_subscript;
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objobjargproc mp_ass_subscript;
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} PyMappingMethods;
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typedef struct {
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getreadbufferproc bf_getreadbuffer;
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getwritebufferproc bf_getwritebuffer;
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getsegcountproc bf_getsegcount;
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getcharbufferproc bf_getcharbuffer;
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} PyBufferProcs;
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typedef void (*destructor)(PyObject *);
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typedef int (*printfunc)(PyObject *, FILE *, int);
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typedef PyObject *(*getattrfunc)(PyObject *, char *);
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typedef PyObject *(*getattrofunc)(PyObject *, PyObject *);
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typedef int (*setattrfunc)(PyObject *, char *, PyObject *);
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typedef int (*setattrofunc)(PyObject *, PyObject *, PyObject *);
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typedef int (*cmpfunc)(PyObject *, PyObject *);
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typedef PyObject *(*reprfunc)(PyObject *);
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typedef long (*hashfunc)(PyObject *);
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typedef PyObject *(*richcmpfunc) (PyObject *, PyObject *, int);
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typedef PyObject *(*getiterfunc) (PyObject *);
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typedef PyObject *(*iternextfunc) (PyObject *);
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typedef PyObject *(*descrgetfunc) (PyObject *, PyObject *, PyObject *);
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typedef int (*descrsetfunc) (PyObject *, PyObject *, PyObject *);
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typedef int (*initproc)(PyObject *, PyObject *, PyObject *);
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typedef PyObject *(*newfunc)(struct _typeobject *, PyObject *, PyObject *);
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typedef PyObject *(*allocfunc)(struct _typeobject *, int);
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typedef struct _typeobject {
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PyObject_VAR_HEAD
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char *tp_name; /* For printing */
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int tp_basicsize, tp_itemsize; /* For allocation */
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/* Methods to implement standard operations */
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destructor tp_dealloc;
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printfunc tp_print;
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getattrfunc tp_getattr;
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setattrfunc tp_setattr;
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cmpfunc tp_compare;
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reprfunc tp_repr;
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/* Method suites for standard classes */
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PyNumberMethods *tp_as_number;
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PySequenceMethods *tp_as_sequence;
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PyMappingMethods *tp_as_mapping;
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/* More standard operations (here for binary compatibility) */
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hashfunc tp_hash;
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ternaryfunc tp_call;
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reprfunc tp_str;
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getattrofunc tp_getattro;
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setattrofunc tp_setattro;
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/* Functions to access object as input/output buffer */
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PyBufferProcs *tp_as_buffer;
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/* Flags to define presence of optional/expanded features */
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long tp_flags;
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char *tp_doc; /* Documentation string */
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/* call function for all accessible objects */
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traverseproc tp_traverse;
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/* delete references to contained objects */
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inquiry tp_clear;
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/* rich comparisons */
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richcmpfunc tp_richcompare;
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/* weak reference enabler */
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long tp_weaklistoffset;
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/* Iterators */
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getiterfunc tp_iter;
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iternextfunc tp_iternext;
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/* Attribute descriptor and subclassing stuff */
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struct PyMethodDef *tp_methods;
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struct memberlist *tp_members;
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struct getsetlist *tp_getset;
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struct _typeobject *tp_base;
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PyObject *tp_dict;
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descrgetfunc tp_descr_get;
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descrsetfunc tp_descr_set;
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long tp_dictoffset;
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initproc tp_init;
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allocfunc tp_alloc;
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newfunc tp_new;
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destructor tp_free; /* Low-level free-memory routine */
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PyObject *tp_bases;
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PyObject *tp_mro; /* method resolution order */
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PyObject *tp_defined;
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#ifdef COUNT_ALLOCS
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/* these must be last and never explicitly initialized */
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int tp_allocs;
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int tp_frees;
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int tp_maxalloc;
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struct _typeobject *tp_next;
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#endif
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} PyTypeObject;
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/* Generic type check */
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extern DL_IMPORT(int) PyType_IsSubtype(PyTypeObject *, PyTypeObject *);
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#define PyObject_TypeCheck(ob, tp) \
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((ob)->ob_type == (tp) || PyType_IsSubtype((ob)->ob_type, (tp)))
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extern DL_IMPORT(PyTypeObject) PyType_Type; /* Metatype */
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extern DL_IMPORT(PyTypeObject) PyBaseObject_Type; /* Most base object type */
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#define PyType_Check(op) PyObject_TypeCheck(op, &PyType_Type)
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extern DL_IMPORT(int) PyType_InitDict(PyTypeObject *);
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extern DL_IMPORT(PyObject *) PyType_GenericAlloc(PyTypeObject *, int);
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extern DL_IMPORT(PyObject *) PyType_GenericNew(PyTypeObject *,
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PyObject *, PyObject *);
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extern DL_IMPORT(PyObject *) _PyType_Lookup(PyTypeObject *, PyObject *);
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/* Generic operations on objects */
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extern DL_IMPORT(int) PyObject_Print(PyObject *, FILE *, int);
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extern DL_IMPORT(void) _PyObject_Dump(PyObject *);
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extern DL_IMPORT(PyObject *) PyObject_Repr(PyObject *);
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extern DL_IMPORT(PyObject *) PyObject_Str(PyObject *);
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extern DL_IMPORT(PyObject *) PyObject_Unicode(PyObject *);
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extern DL_IMPORT(int) PyObject_Compare(PyObject *, PyObject *);
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extern DL_IMPORT(PyObject *) PyObject_RichCompare(PyObject *, PyObject *, int);
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extern DL_IMPORT(int) PyObject_RichCompareBool(PyObject *, PyObject *, int);
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extern DL_IMPORT(PyObject *) PyObject_GetAttrString(PyObject *, char *);
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extern DL_IMPORT(int) PyObject_SetAttrString(PyObject *, char *, PyObject *);
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extern DL_IMPORT(int) PyObject_HasAttrString(PyObject *, char *);
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extern DL_IMPORT(PyObject *) PyObject_GetAttr(PyObject *, PyObject *);
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extern DL_IMPORT(int) PyObject_SetAttr(PyObject *, PyObject *, PyObject *);
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extern DL_IMPORT(int) PyObject_HasAttr(PyObject *, PyObject *);
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extern DL_IMPORT(PyObject **) _PyObject_GetDictPtr(PyObject *);
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extern DL_IMPORT(PyObject *) PyObject_GenericGetAttr(PyObject *, PyObject *);
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extern DL_IMPORT(int) PyObject_GenericSetAttr(PyObject *,
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PyObject *, PyObject *);
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extern DL_IMPORT(long) PyObject_Hash(PyObject *);
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extern DL_IMPORT(int) PyObject_IsTrue(PyObject *);
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extern DL_IMPORT(int) PyObject_Not(PyObject *);
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extern DL_IMPORT(int) PyCallable_Check(PyObject *);
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extern DL_IMPORT(int) PyNumber_Coerce(PyObject **, PyObject **);
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extern DL_IMPORT(int) PyNumber_CoerceEx(PyObject **, PyObject **);
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extern DL_IMPORT(void) (*PyObject_ClearWeakRefs)(PyObject *);
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/* Helpers for printing recursive container types */
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extern DL_IMPORT(int) Py_ReprEnter(PyObject *);
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extern DL_IMPORT(void) Py_ReprLeave(PyObject *);
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/* Helpers for hash functions */
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extern DL_IMPORT(long) _Py_HashDouble(double);
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extern DL_IMPORT(long) _Py_HashPointer(void*);
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/* Helper for passing objects to printf and the like */
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#define PyObject_REPR(obj) PyString_AS_STRING(PyObject_Repr(obj))
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/* Flag bits for printing: */
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#define Py_PRINT_RAW 1 /* No string quotes etc. */
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/*
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Type flags (tp_flags)
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These flags are used to extend the type structure in a backwards-compatible
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fashion. Extensions can use the flags to indicate (and test) when a given
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type structure contains a new feature. The Python core will use these when
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introducing new functionality between major revisions (to avoid mid-version
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changes in the PYTHON_API_VERSION).
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Arbitration of the flag bit positions will need to be coordinated among
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all extension writers who publically release their extensions (this will
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be fewer than you might expect!)..
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Python 1.5.2 introduced the bf_getcharbuffer slot into PyBufferProcs.
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Type definitions should use Py_TPFLAGS_DEFAULT for their tp_flags value.
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Code can use PyType_HasFeature(type_ob, flag_value) to test whether the
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given type object has a specified feature.
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*/
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/* PyBufferProcs contains bf_getcharbuffer */
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#define Py_TPFLAGS_HAVE_GETCHARBUFFER (1L<<0)
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/* PySequenceMethods contains sq_contains */
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#define Py_TPFLAGS_HAVE_SEQUENCE_IN (1L<<1)
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/* Objects which participate in garbage collection (see objimp.h) */
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#ifdef WITH_CYCLE_GC
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#define Py_TPFLAGS_GC (1L<<2)
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#else
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#define Py_TPFLAGS_GC 0
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#endif
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/* PySequenceMethods and PyNumberMethods contain in-place operators */
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#define Py_TPFLAGS_HAVE_INPLACEOPS (1L<<3)
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/* PyNumberMethods do their own coercion */
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#define Py_TPFLAGS_CHECKTYPES (1L<<4)
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/* tp_richcompare is defined */
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#define Py_TPFLAGS_HAVE_RICHCOMPARE (1L<<5)
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/* Objects which are weakly referencable if their tp_weaklistoffset is >0 */
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#define Py_TPFLAGS_HAVE_WEAKREFS (1L<<6)
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/* tp_iter is defined */
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#define Py_TPFLAGS_HAVE_ITER (1L<<7)
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/* Experimental stuff for healing the type/class split */
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#define Py_TPFLAGS_HAVE_CLASS (1L<<8)
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/* Set if the type object is dynamically allocated */
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#define Py_TPFLAGS_HEAPTYPE (1L<<9)
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/* Set if the type allows subclassing */
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#define Py_TPFLAGS_BASETYPE (1L<<10)
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/* Set if the type's __dict__ may change */
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#define Py_TPFLAGS_DYNAMICTYPE (1L<<11)
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#define Py_TPFLAGS_DEFAULT ( \
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Py_TPFLAGS_HAVE_GETCHARBUFFER | \
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Py_TPFLAGS_HAVE_SEQUENCE_IN | \
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Py_TPFLAGS_HAVE_INPLACEOPS | \
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Py_TPFLAGS_HAVE_RICHCOMPARE | \
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Py_TPFLAGS_HAVE_WEAKREFS | \
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Py_TPFLAGS_HAVE_ITER | \
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Py_TPFLAGS_HAVE_CLASS | \
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0)
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#define PyType_HasFeature(t,f) (((t)->tp_flags & (f)) != 0)
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/*
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The macros Py_INCREF(op) and Py_DECREF(op) are used to increment or decrement
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reference counts. Py_DECREF calls the object's deallocator function; for
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objects that don't contain references to other objects or heap memory
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this can be the standard function free(). Both macros can be used
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wherever a void expression is allowed. The argument shouldn't be a
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NIL pointer. The macro _Py_NewReference(op) is used only to initialize
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reference counts to 1; it is defined here for convenience.
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We assume that the reference count field can never overflow; this can
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be proven when the size of the field is the same as the pointer size
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but even with a 16-bit reference count field it is pretty unlikely so
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we ignore the possibility. (If you are paranoid, make it a long.)
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Type objects should never be deallocated; the type pointer in an object
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is not considered to be a reference to the type object, to save
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complications in the deallocation function. (This is actually a
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decision that's up to the implementer of each new type so if you want,
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you can count such references to the type object.)
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*** WARNING*** The Py_DECREF macro must have a side-effect-free argument
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since it may evaluate its argument multiple times. (The alternative
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would be to mace it a proper function or assign it to a global temporary
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variable first, both of which are slower; and in a multi-threaded
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environment the global variable trick is not safe.)
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*/
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#ifdef Py_TRACE_REFS
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#ifndef Py_REF_DEBUG
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#define Py_REF_DEBUG
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#endif
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#endif
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#ifdef Py_TRACE_REFS
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extern DL_IMPORT(void) _Py_Dealloc(PyObject *);
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extern DL_IMPORT(void) _Py_NewReference(PyObject *);
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extern DL_IMPORT(void) _Py_ForgetReference(PyObject *);
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extern DL_IMPORT(void) _Py_PrintReferences(FILE *);
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extern DL_IMPORT(void) _Py_ResetReferences(void);
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#endif
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#ifndef Py_TRACE_REFS
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#ifdef COUNT_ALLOCS
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#define _Py_Dealloc(op) ((op)->ob_type->tp_frees++, (*(op)->ob_type->tp_dealloc)((PyObject *)(op)))
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#define _Py_ForgetReference(op) ((op)->ob_type->tp_frees++)
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#else /* !COUNT_ALLOCS */
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#define _Py_Dealloc(op) (*(op)->ob_type->tp_dealloc)((PyObject *)(op))
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#define _Py_ForgetReference(op) /*empty*/
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#endif /* !COUNT_ALLOCS */
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#endif /* !Py_TRACE_REFS */
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#ifdef COUNT_ALLOCS
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extern DL_IMPORT(void) inc_count(PyTypeObject *);
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#endif
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#ifdef Py_REF_DEBUG
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extern DL_IMPORT(long) _Py_RefTotal;
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#ifndef Py_TRACE_REFS
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#ifdef COUNT_ALLOCS
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#define _Py_NewReference(op) (inc_count((op)->ob_type), _Py_RefTotal++, (op)->ob_refcnt = 1)
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#else
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#define _Py_NewReference(op) (_Py_RefTotal++, (op)->ob_refcnt = 1)
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#endif
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#endif /* !Py_TRACE_REFS */
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#define Py_INCREF(op) (_Py_RefTotal++, (op)->ob_refcnt++)
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#define Py_DECREF(op) \
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if (--_Py_RefTotal, (--((op)->ob_refcnt) != 0)) \
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; \
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else \
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_Py_Dealloc((PyObject *)(op))
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#else /* !Py_REF_DEBUG */
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#ifdef COUNT_ALLOCS
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#define _Py_NewReference(op) (inc_count((op)->ob_type), (op)->ob_refcnt = 1)
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#else
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#define _Py_NewReference(op) ((op)->ob_refcnt = 1)
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#endif
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#define Py_INCREF(op) ((op)->ob_refcnt++)
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#define Py_DECREF(op) \
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|
if (--(op)->ob_refcnt != 0) \
|
|
; \
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|
else \
|
|
_Py_Dealloc((PyObject *)(op))
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|
#endif /* !Py_REF_DEBUG */
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/* Macros to use in case the object pointer may be NULL: */
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#define Py_XINCREF(op) if ((op) == NULL) ; else Py_INCREF(op)
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#define Py_XDECREF(op) if ((op) == NULL) ; else Py_DECREF(op)
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|
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/*
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|
_Py_NoneStruct is an object of undefined type which can be used in contexts
|
|
where NULL (nil) is not suitable (since NULL often means 'error').
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|
|
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Don't forget to apply Py_INCREF() when returning this value!!!
|
|
*/
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|
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extern DL_IMPORT(PyObject) _Py_NoneStruct; /* Don't use this directly */
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|
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#define Py_None (&_Py_NoneStruct)
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|
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/*
|
|
Py_NotImplemented is a singleton used to signal that an operation is
|
|
not implemented for a given type combination.
|
|
*/
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|
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extern DL_IMPORT(PyObject) _Py_NotImplementedStruct; /* Don't use this directly */
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|
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#define Py_NotImplemented (&_Py_NotImplementedStruct)
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|
|
/* Rich comparison opcodes */
|
|
#define Py_LT 0
|
|
#define Py_LE 1
|
|
#define Py_EQ 2
|
|
#define Py_NE 3
|
|
#define Py_GT 4
|
|
#define Py_GE 5
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|
|
|
/*
|
|
A common programming style in Python requires the forward declaration
|
|
of static, initialized structures, e.g. for a type object that is used
|
|
by the functions whose address must be used in the initializer.
|
|
Some compilers (notably SCO ODT 3.0, I seem to remember early AIX as
|
|
well) botch this if you use the static keyword for both declarations
|
|
(they allocate two objects, and use the first, uninitialized one until
|
|
the second declaration is encountered). Therefore, the forward
|
|
declaration should use the 'forwardstatic' keyword. This expands to
|
|
static on most systems, but to extern on a few. The actual storage
|
|
and name will still be static because the second declaration is
|
|
static, so no linker visible symbols will be generated. (Standard C
|
|
compilers take offense to the extern forward declaration of a static
|
|
object, so I can't just put extern in all cases. :-( )
|
|
*/
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|
|
|
#ifdef BAD_STATIC_FORWARD
|
|
#define staticforward extern
|
|
#define statichere static
|
|
#else /* !BAD_STATIC_FORWARD */
|
|
#define staticforward static
|
|
#define statichere static
|
|
#endif /* !BAD_STATIC_FORWARD */
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|
|
|
|
|
/*
|
|
More conventions
|
|
================
|
|
|
|
Argument Checking
|
|
-----------------
|
|
|
|
Functions that take objects as arguments normally don't check for nil
|
|
arguments, but they do check the type of the argument, and return an
|
|
error if the function doesn't apply to the type.
|
|
|
|
Failure Modes
|
|
-------------
|
|
|
|
Functions may fail for a variety of reasons, including running out of
|
|
memory. This is communicated to the caller in two ways: an error string
|
|
is set (see errors.h), and the function result differs: functions that
|
|
normally return a pointer return NULL for failure, functions returning
|
|
an integer return -1 (which could be a legal return value too!), and
|
|
other functions return 0 for success and -1 for failure.
|
|
Callers should always check for errors before using the result.
|
|
|
|
Reference Counts
|
|
----------------
|
|
|
|
It takes a while to get used to the proper usage of reference counts.
|
|
|
|
Functions that create an object set the reference count to 1; such new
|
|
objects must be stored somewhere or destroyed again with Py_DECREF().
|
|
Functions that 'store' objects such as PyTuple_SetItem() and
|
|
PyDict_SetItemString()
|
|
don't increment the reference count of the object, since the most
|
|
frequent use is to store a fresh object. Functions that 'retrieve'
|
|
objects such as PyTuple_GetItem() and PyDict_GetItemString() also
|
|
don't increment
|
|
the reference count, since most frequently the object is only looked at
|
|
quickly. Thus, to retrieve an object and store it again, the caller
|
|
must call Py_INCREF() explicitly.
|
|
|
|
NOTE: functions that 'consume' a reference count like
|
|
PyList_SetItemString() even consume the reference if the object wasn't
|
|
stored, to simplify error handling.
|
|
|
|
It seems attractive to make other functions that take an object as
|
|
argument consume a reference count; however this may quickly get
|
|
confusing (even the current practice is already confusing). Consider
|
|
it carefully, it may save lots of calls to Py_INCREF() and Py_DECREF() at
|
|
times.
|
|
*/
|
|
|
|
/*
|
|
trashcan
|
|
CT 2k0130
|
|
non-recursively destroy nested objects
|
|
|
|
CT 2k0223
|
|
redefinition for better locality and less overhead.
|
|
|
|
Objects that want to be recursion safe need to use
|
|
the macro's
|
|
Py_TRASHCAN_SAFE_BEGIN(name)
|
|
and
|
|
Py_TRASHCAN_SAFE_END(name)
|
|
surrounding their actual deallocation code.
|
|
|
|
It would be nice to do this using the thread state.
|
|
Also, we could do an exact stack measure then.
|
|
Unfortunately, deallocations also take place when
|
|
the thread state is undefined.
|
|
|
|
CT 2k0422 complete rewrite.
|
|
There is no need to allocate new objects.
|
|
Everything is done vialob_refcnt and ob_type now.
|
|
Adding support for free-threading should be easy, too.
|
|
*/
|
|
|
|
#define PyTrash_UNWIND_LEVEL 50
|
|
|
|
#define Py_TRASHCAN_SAFE_BEGIN(op) \
|
|
{ \
|
|
++_PyTrash_delete_nesting; \
|
|
if (_PyTrash_delete_nesting < PyTrash_UNWIND_LEVEL) { \
|
|
|
|
#define Py_TRASHCAN_SAFE_END(op) \
|
|
;} \
|
|
else \
|
|
_PyTrash_deposit_object((PyObject*)op);\
|
|
--_PyTrash_delete_nesting; \
|
|
if (_PyTrash_delete_later && _PyTrash_delete_nesting <= 0) \
|
|
_PyTrash_destroy_chain(); \
|
|
} \
|
|
|
|
extern DL_IMPORT(void) _PyTrash_deposit_object(PyObject*);
|
|
extern DL_IMPORT(void) _PyTrash_destroy_chain(void);
|
|
|
|
extern DL_IMPORT(int) _PyTrash_delete_nesting;
|
|
extern DL_IMPORT(PyObject *) _PyTrash_delete_later;
|
|
|
|
/* swap the "xx" to check the speed loss */
|
|
|
|
#define xxPy_TRASHCAN_SAFE_BEGIN(op)
|
|
#define xxPy_TRASHCAN_SAFE_END(op) ;
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
#endif /* !Py_OBJECT_H */
|