1105 lines
41 KiB
C
1105 lines
41 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, although work on type/class unification
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for Python 2.2 made it possible to have heap-allocated type objects too).
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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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/* Py_DEBUG implies Py_TRACE_REFS. */
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#if defined(Py_DEBUG) && !defined(Py_TRACE_REFS)
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#define Py_TRACE_REFS
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#endif
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/* Py_TRACE_REFS implies Py_REF_DEBUG. */
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#if defined(Py_TRACE_REFS) && !defined(Py_REF_DEBUG)
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#define Py_REF_DEBUG
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#endif
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#if defined(Py_LIMITED_API) && defined(Py_REF_DEBUG)
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#error Py_LIMITED_API is incompatible with Py_DEBUG, Py_TRACE_REFS, and Py_REF_DEBUG
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#endif
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#ifdef Py_TRACE_REFS
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/* Define pointers to support a doubly-linked list of all live heap objects. */
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#define _PyObject_HEAD_EXTRA \
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struct _object *_ob_next; \
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struct _object *_ob_prev;
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#define _PyObject_EXTRA_INIT 0, 0,
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#else
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#define _PyObject_HEAD_EXTRA
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#define _PyObject_EXTRA_INIT
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#endif
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/* PyObject_HEAD defines the initial segment of every PyObject. */
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#define PyObject_HEAD PyObject ob_base;
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#define PyObject_HEAD_INIT(type) \
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{ _PyObject_EXTRA_INIT \
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1, type },
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#define PyVarObject_HEAD_INIT(type, size) \
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{ PyObject_HEAD_INIT(type) size },
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/* PyObject_VAR_HEAD defines the initial segment of all variable-size
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* container objects. These end with a declaration of an array with 1
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* element, but enough space is malloc'ed so that the array actually
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* has room for ob_size elements. Note that ob_size is an element count,
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* not necessarily a byte count.
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*/
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#define PyObject_VAR_HEAD PyVarObject ob_base;
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#define Py_INVALID_SIZE (Py_ssize_t)-1
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/* Nothing is actually declared to be a PyObject, but every pointer to
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* a Python object can be cast to a PyObject*. This is inheritance built
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* by hand. Similarly every pointer to a variable-size Python object can,
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* in addition, be cast to PyVarObject*.
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*/
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typedef struct _object {
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_PyObject_HEAD_EXTRA
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Py_ssize_t ob_refcnt;
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struct _typeobject *ob_type;
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} PyObject;
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typedef struct {
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PyObject ob_base;
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Py_ssize_t ob_size; /* Number of items in variable part */
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} PyVarObject;
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#define Py_REFCNT(ob) (((PyObject*)(ob))->ob_refcnt)
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#define Py_TYPE(ob) (((PyObject*)(ob))->ob_type)
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#define Py_SIZE(ob) (((PyVarObject*)(ob))->ob_size)
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#ifndef Py_LIMITED_API
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/********************* String Literals ****************************************/
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/* This structure helps managing static strings. The basic usage goes like this:
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Instead of doing
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r = PyObject_CallMethod(o, "foo", "args", ...);
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do
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_Py_IDENTIFIER(foo);
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...
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r = _PyObject_CallMethodId(o, &PyId_foo, "args", ...);
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PyId_foo is a static variable, either on block level or file level. On first
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usage, the string "foo" is interned, and the structures are linked. On interpreter
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shutdown, all strings are released (through _PyUnicode_ClearStaticStrings).
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Alternatively, _Py_static_string allows choosing the variable name.
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_PyUnicode_FromId returns a borrowed reference to the interned string.
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_PyObject_{Get,Set,Has}AttrId are __getattr__ versions using _Py_Identifier*.
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*/
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typedef struct _Py_Identifier {
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struct _Py_Identifier *next;
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const char* string;
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PyObject *object;
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} _Py_Identifier;
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#define _Py_static_string_init(value) { .next = NULL, .string = value, .object = NULL }
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#define _Py_static_string(varname, value) static _Py_Identifier varname = _Py_static_string_init(value)
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#define _Py_IDENTIFIER(varname) _Py_static_string(PyId_##varname, #varname)
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#endif /* !Py_LIMITED_API */
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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 PyObject_New() and
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PyObject_NewVar()),
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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 statically allocated 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 Py_ssize_t (*lenfunc)(PyObject *);
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typedef PyObject *(*ssizeargfunc)(PyObject *, Py_ssize_t);
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typedef PyObject *(*ssizessizeargfunc)(PyObject *, Py_ssize_t, Py_ssize_t);
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typedef int(*ssizeobjargproc)(PyObject *, Py_ssize_t, PyObject *);
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typedef int(*ssizessizeobjargproc)(PyObject *, Py_ssize_t, Py_ssize_t, PyObject *);
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typedef int(*objobjargproc)(PyObject *, PyObject *, PyObject *);
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#ifndef Py_LIMITED_API
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/* buffer interface */
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typedef struct bufferinfo {
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void *buf;
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PyObject *obj; /* owned reference */
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Py_ssize_t len;
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Py_ssize_t itemsize; /* This is Py_ssize_t so it can be
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pointed to by strides in simple case.*/
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int readonly;
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int ndim;
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char *format;
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Py_ssize_t *shape;
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Py_ssize_t *strides;
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Py_ssize_t *suboffsets;
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void *internal;
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} Py_buffer;
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typedef int (*getbufferproc)(PyObject *, Py_buffer *, int);
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typedef void (*releasebufferproc)(PyObject *, Py_buffer *);
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/* Maximum number of dimensions */
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#define PyBUF_MAX_NDIM 64
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/* Flags for getting buffers */
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#define PyBUF_SIMPLE 0
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#define PyBUF_WRITABLE 0x0001
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/* we used to include an E, backwards compatible alias */
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#define PyBUF_WRITEABLE PyBUF_WRITABLE
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#define PyBUF_FORMAT 0x0004
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#define PyBUF_ND 0x0008
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#define PyBUF_STRIDES (0x0010 | PyBUF_ND)
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#define PyBUF_C_CONTIGUOUS (0x0020 | PyBUF_STRIDES)
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#define PyBUF_F_CONTIGUOUS (0x0040 | PyBUF_STRIDES)
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#define PyBUF_ANY_CONTIGUOUS (0x0080 | PyBUF_STRIDES)
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#define PyBUF_INDIRECT (0x0100 | PyBUF_STRIDES)
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#define PyBUF_CONTIG (PyBUF_ND | PyBUF_WRITABLE)
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#define PyBUF_CONTIG_RO (PyBUF_ND)
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#define PyBUF_STRIDED (PyBUF_STRIDES | PyBUF_WRITABLE)
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#define PyBUF_STRIDED_RO (PyBUF_STRIDES)
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#define PyBUF_RECORDS (PyBUF_STRIDES | PyBUF_WRITABLE | PyBUF_FORMAT)
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#define PyBUF_RECORDS_RO (PyBUF_STRIDES | PyBUF_FORMAT)
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#define PyBUF_FULL (PyBUF_INDIRECT | PyBUF_WRITABLE | PyBUF_FORMAT)
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#define PyBUF_FULL_RO (PyBUF_INDIRECT | PyBUF_FORMAT)
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#define PyBUF_READ 0x100
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#define PyBUF_WRITE 0x200
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/* End buffer interface */
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#endif /* Py_LIMITED_API */
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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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#ifndef Py_LIMITED_API
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typedef struct {
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/* Number implementations must 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_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_bool;
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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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unaryfunc nb_int;
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void *nb_reserved; /* the slot formerly known as nb_long */
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unaryfunc nb_float;
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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_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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binaryfunc nb_floor_divide;
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binaryfunc nb_true_divide;
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binaryfunc nb_inplace_floor_divide;
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binaryfunc nb_inplace_true_divide;
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unaryfunc nb_index;
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binaryfunc nb_matrix_multiply;
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binaryfunc nb_inplace_matrix_multiply;
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} PyNumberMethods;
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typedef struct {
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lenfunc sq_length;
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binaryfunc sq_concat;
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ssizeargfunc sq_repeat;
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ssizeargfunc sq_item;
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void *was_sq_slice;
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ssizeobjargproc sq_ass_item;
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void *was_sq_ass_slice;
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objobjproc sq_contains;
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binaryfunc sq_inplace_concat;
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ssizeargfunc sq_inplace_repeat;
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} PySequenceMethods;
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typedef struct {
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lenfunc 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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unaryfunc am_await;
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unaryfunc am_aiter;
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unaryfunc am_anext;
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} PyAsyncMethods;
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typedef struct {
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getbufferproc bf_getbuffer;
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releasebufferproc bf_releasebuffer;
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} PyBufferProcs;
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#endif /* Py_LIMITED_API */
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typedef void (*freefunc)(void *);
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typedef void (*destructor)(PyObject *);
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#ifndef Py_LIMITED_API
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/* We can't provide a full compile-time check that limited-API
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users won't implement tp_print. However, not defining printfunc
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and making tp_print of a different function pointer type
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should at least cause a warning in most cases. */
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typedef int (*printfunc)(PyObject *, FILE *, int);
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#endif
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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 PyObject *(*reprfunc)(PyObject *);
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typedef Py_hash_t (*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 *, Py_ssize_t);
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#ifdef Py_LIMITED_API
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typedef struct _typeobject PyTypeObject; /* opaque */
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#else
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typedef struct _typeobject {
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PyObject_VAR_HEAD
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const char *tp_name; /* For printing, in format "<module>.<name>" */
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Py_ssize_t 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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PyAsyncMethods *tp_as_async; /* formerly known as tp_compare (Python 2)
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or tp_reserved (Python 3) */
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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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unsigned long tp_flags;
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const char *tp_doc; /* Documentation string */
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/* Assigned meaning in release 2.0 */
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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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/* Assigned meaning in release 2.1 */
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/* rich comparisons */
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richcmpfunc tp_richcompare;
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/* weak reference enabler */
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Py_ssize_t 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 PyMemberDef *tp_members;
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struct PyGetSetDef *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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Py_ssize_t 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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freefunc tp_free; /* Low-level free-memory routine */
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inquiry tp_is_gc; /* For PyObject_IS_GC */
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PyObject *tp_bases;
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PyObject *tp_mro; /* method resolution order */
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PyObject *tp_cache;
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PyObject *tp_subclasses;
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PyObject *tp_weaklist;
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destructor tp_del;
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/* Type attribute cache version tag. Added in version 2.6 */
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unsigned int tp_version_tag;
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destructor tp_finalize;
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#ifdef COUNT_ALLOCS
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/* these must be last and never explicitly initialized */
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Py_ssize_t tp_allocs;
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Py_ssize_t tp_frees;
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Py_ssize_t tp_maxalloc;
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struct _typeobject *tp_prev;
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struct _typeobject *tp_next;
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#endif
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} PyTypeObject;
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#endif
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typedef struct{
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int slot; /* slot id, see below */
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void *pfunc; /* function pointer */
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} PyType_Slot;
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typedef struct{
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const char* name;
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int basicsize;
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int itemsize;
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unsigned int flags;
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PyType_Slot *slots; /* terminated by slot==0. */
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} PyType_Spec;
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PyAPI_FUNC(PyObject*) PyType_FromSpec(PyType_Spec*);
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#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03030000
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PyAPI_FUNC(PyObject*) PyType_FromSpecWithBases(PyType_Spec*, PyObject*);
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#endif
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#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03040000
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PyAPI_FUNC(void*) PyType_GetSlot(PyTypeObject*, int);
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#endif
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#ifndef Py_LIMITED_API
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/* The *real* layout of a type object when allocated on the heap */
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typedef struct _heaptypeobject {
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/* Note: there's a dependency on the order of these members
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in slotptr() in typeobject.c . */
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PyTypeObject ht_type;
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PyAsyncMethods as_async;
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PyNumberMethods as_number;
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PyMappingMethods as_mapping;
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PySequenceMethods as_sequence; /* as_sequence comes after as_mapping,
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so that the mapping wins when both
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the mapping and the sequence define
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a given operator (e.g. __getitem__).
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see add_operators() in typeobject.c . */
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PyBufferProcs as_buffer;
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PyObject *ht_name, *ht_slots, *ht_qualname;
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struct _dictkeysobject *ht_cached_keys;
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/* here are optional user slots, followed by the members. */
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} PyHeapTypeObject;
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|
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/* access macro to the members which are floating "behind" the object */
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#define PyHeapType_GET_MEMBERS(etype) \
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((PyMemberDef *)(((char *)etype) + Py_TYPE(etype)->tp_basicsize))
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#endif
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/* Generic type check */
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PyAPI_FUNC(int) PyType_IsSubtype(PyTypeObject *, PyTypeObject *);
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|
#define PyObject_TypeCheck(ob, tp) \
|
|
(Py_TYPE(ob) == (tp) || PyType_IsSubtype(Py_TYPE(ob), (tp)))
|
|
|
|
PyAPI_DATA(PyTypeObject) PyType_Type; /* built-in 'type' */
|
|
PyAPI_DATA(PyTypeObject) PyBaseObject_Type; /* built-in 'object' */
|
|
PyAPI_DATA(PyTypeObject) PySuper_Type; /* built-in 'super' */
|
|
|
|
PyAPI_FUNC(unsigned long) PyType_GetFlags(PyTypeObject*);
|
|
|
|
#define PyType_Check(op) \
|
|
PyType_FastSubclass(Py_TYPE(op), Py_TPFLAGS_TYPE_SUBCLASS)
|
|
#define PyType_CheckExact(op) (Py_TYPE(op) == &PyType_Type)
|
|
|
|
PyAPI_FUNC(int) PyType_Ready(PyTypeObject *);
|
|
PyAPI_FUNC(PyObject *) PyType_GenericAlloc(PyTypeObject *, Py_ssize_t);
|
|
PyAPI_FUNC(PyObject *) PyType_GenericNew(PyTypeObject *,
|
|
PyObject *, PyObject *);
|
|
#ifndef Py_LIMITED_API
|
|
PyAPI_FUNC(const char *) _PyType_Name(PyTypeObject *);
|
|
PyAPI_FUNC(PyObject *) _PyType_Lookup(PyTypeObject *, PyObject *);
|
|
PyAPI_FUNC(PyObject *) _PyType_LookupId(PyTypeObject *, _Py_Identifier *);
|
|
PyAPI_FUNC(PyObject *) _PyObject_LookupSpecial(PyObject *, _Py_Identifier *);
|
|
PyAPI_FUNC(PyTypeObject *) _PyType_CalculateMetaclass(PyTypeObject *, PyObject *);
|
|
#endif
|
|
PyAPI_FUNC(unsigned int) PyType_ClearCache(void);
|
|
PyAPI_FUNC(void) PyType_Modified(PyTypeObject *);
|
|
|
|
#ifndef Py_LIMITED_API
|
|
PyAPI_FUNC(PyObject *) _PyType_GetDocFromInternalDoc(const char *, const char *);
|
|
PyAPI_FUNC(PyObject *) _PyType_GetTextSignatureFromInternalDoc(const char *, const char *);
|
|
#endif
|
|
|
|
/* Generic operations on objects */
|
|
#ifndef Py_LIMITED_API
|
|
struct _Py_Identifier;
|
|
PyAPI_FUNC(int) PyObject_Print(PyObject *, FILE *, int);
|
|
PyAPI_FUNC(void) _Py_BreakPoint(void);
|
|
PyAPI_FUNC(void) _PyObject_Dump(PyObject *);
|
|
PyAPI_FUNC(int) _PyObject_IsFreed(PyObject *);
|
|
#endif
|
|
PyAPI_FUNC(PyObject *) PyObject_Repr(PyObject *);
|
|
PyAPI_FUNC(PyObject *) PyObject_Str(PyObject *);
|
|
PyAPI_FUNC(PyObject *) PyObject_ASCII(PyObject *);
|
|
PyAPI_FUNC(PyObject *) PyObject_Bytes(PyObject *);
|
|
PyAPI_FUNC(PyObject *) PyObject_RichCompare(PyObject *, PyObject *, int);
|
|
PyAPI_FUNC(int) PyObject_RichCompareBool(PyObject *, PyObject *, int);
|
|
PyAPI_FUNC(PyObject *) PyObject_GetAttrString(PyObject *, const char *);
|
|
PyAPI_FUNC(int) PyObject_SetAttrString(PyObject *, const char *, PyObject *);
|
|
PyAPI_FUNC(int) PyObject_HasAttrString(PyObject *, const char *);
|
|
PyAPI_FUNC(PyObject *) PyObject_GetAttr(PyObject *, PyObject *);
|
|
PyAPI_FUNC(int) PyObject_SetAttr(PyObject *, PyObject *, PyObject *);
|
|
PyAPI_FUNC(int) PyObject_HasAttr(PyObject *, PyObject *);
|
|
#ifndef Py_LIMITED_API
|
|
PyAPI_FUNC(int) _PyObject_IsAbstract(PyObject *);
|
|
PyAPI_FUNC(PyObject *) _PyObject_GetAttrId(PyObject *, struct _Py_Identifier *);
|
|
PyAPI_FUNC(int) _PyObject_SetAttrId(PyObject *, struct _Py_Identifier *, PyObject *);
|
|
PyAPI_FUNC(int) _PyObject_HasAttrId(PyObject *, struct _Py_Identifier *);
|
|
/* Replacements of PyObject_GetAttr() and _PyObject_GetAttrId() which
|
|
don't raise AttributeError.
|
|
|
|
Return 1 and set *result != NULL if an attribute is found.
|
|
Return 0 and set *result == NULL if an attribute is not found;
|
|
an AttributeError is silenced.
|
|
Return -1 and set *result == NULL if an error other than AttributeError
|
|
is raised.
|
|
*/
|
|
PyAPI_FUNC(int) _PyObject_LookupAttr(PyObject *, PyObject *, PyObject **);
|
|
PyAPI_FUNC(int) _PyObject_LookupAttrId(PyObject *, struct _Py_Identifier *, PyObject **);
|
|
PyAPI_FUNC(PyObject **) _PyObject_GetDictPtr(PyObject *);
|
|
#endif
|
|
PyAPI_FUNC(PyObject *) PyObject_SelfIter(PyObject *);
|
|
#ifndef Py_LIMITED_API
|
|
PyAPI_FUNC(PyObject *) _PyObject_NextNotImplemented(PyObject *);
|
|
#endif
|
|
PyAPI_FUNC(PyObject *) PyObject_GenericGetAttr(PyObject *, PyObject *);
|
|
PyAPI_FUNC(int) PyObject_GenericSetAttr(PyObject *,
|
|
PyObject *, PyObject *);
|
|
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03030000
|
|
PyAPI_FUNC(int) PyObject_GenericSetDict(PyObject *, PyObject *, void *);
|
|
#endif
|
|
PyAPI_FUNC(Py_hash_t) PyObject_Hash(PyObject *);
|
|
PyAPI_FUNC(Py_hash_t) PyObject_HashNotImplemented(PyObject *);
|
|
PyAPI_FUNC(int) PyObject_IsTrue(PyObject *);
|
|
PyAPI_FUNC(int) PyObject_Not(PyObject *);
|
|
PyAPI_FUNC(int) PyCallable_Check(PyObject *);
|
|
|
|
PyAPI_FUNC(void) PyObject_ClearWeakRefs(PyObject *);
|
|
#ifndef Py_LIMITED_API
|
|
PyAPI_FUNC(void) PyObject_CallFinalizer(PyObject *);
|
|
PyAPI_FUNC(int) PyObject_CallFinalizerFromDealloc(PyObject *);
|
|
#endif
|
|
|
|
#ifndef Py_LIMITED_API
|
|
/* Same as PyObject_Generic{Get,Set}Attr, but passing the attributes
|
|
dict as the last parameter. */
|
|
PyAPI_FUNC(PyObject *)
|
|
_PyObject_GenericGetAttrWithDict(PyObject *, PyObject *, PyObject *, int);
|
|
PyAPI_FUNC(int)
|
|
_PyObject_GenericSetAttrWithDict(PyObject *, PyObject *,
|
|
PyObject *, PyObject *);
|
|
#endif /* !Py_LIMITED_API */
|
|
|
|
/* Helper to look up a builtin object */
|
|
#ifndef Py_LIMITED_API
|
|
PyAPI_FUNC(PyObject *)
|
|
_PyObject_GetBuiltin(const char *name);
|
|
#endif
|
|
|
|
/* PyObject_Dir(obj) acts like Python builtins.dir(obj), returning a
|
|
list of strings. PyObject_Dir(NULL) is like builtins.dir(),
|
|
returning the names of the current locals. In this case, if there are
|
|
no current locals, NULL is returned, and PyErr_Occurred() is false.
|
|
*/
|
|
PyAPI_FUNC(PyObject *) PyObject_Dir(PyObject *);
|
|
|
|
|
|
/* Helpers for printing recursive container types */
|
|
PyAPI_FUNC(int) Py_ReprEnter(PyObject *);
|
|
PyAPI_FUNC(void) Py_ReprLeave(PyObject *);
|
|
|
|
/* Flag bits for printing: */
|
|
#define Py_PRINT_RAW 1 /* No string quotes etc. */
|
|
|
|
/*
|
|
`Type flags (tp_flags)
|
|
|
|
These flags are used to extend the type structure in a backwards-compatible
|
|
fashion. Extensions can use the flags to indicate (and test) when a given
|
|
type structure contains a new feature. The Python core will use these when
|
|
introducing new functionality between major revisions (to avoid mid-version
|
|
changes in the PYTHON_API_VERSION).
|
|
|
|
Arbitration of the flag bit positions will need to be coordinated among
|
|
all extension writers who publicly release their extensions (this will
|
|
be fewer than you might expect!)..
|
|
|
|
Most flags were removed as of Python 3.0 to make room for new flags. (Some
|
|
flags are not for backwards compatibility but to indicate the presence of an
|
|
optional feature; these flags remain of course.)
|
|
|
|
Type definitions should use Py_TPFLAGS_DEFAULT for their tp_flags value.
|
|
|
|
Code can use PyType_HasFeature(type_ob, flag_value) to test whether the
|
|
given type object has a specified feature.
|
|
*/
|
|
|
|
/* Set if the type object is dynamically allocated */
|
|
#define Py_TPFLAGS_HEAPTYPE (1UL << 9)
|
|
|
|
/* Set if the type allows subclassing */
|
|
#define Py_TPFLAGS_BASETYPE (1UL << 10)
|
|
|
|
/* Set if the type is 'ready' -- fully initialized */
|
|
#define Py_TPFLAGS_READY (1UL << 12)
|
|
|
|
/* Set while the type is being 'readied', to prevent recursive ready calls */
|
|
#define Py_TPFLAGS_READYING (1UL << 13)
|
|
|
|
/* Objects support garbage collection (see objimp.h) */
|
|
#define Py_TPFLAGS_HAVE_GC (1UL << 14)
|
|
|
|
/* These two bits are preserved for Stackless Python, next after this is 17 */
|
|
#ifdef STACKLESS
|
|
#define Py_TPFLAGS_HAVE_STACKLESS_EXTENSION (3UL << 15)
|
|
#else
|
|
#define Py_TPFLAGS_HAVE_STACKLESS_EXTENSION 0
|
|
#endif
|
|
|
|
/* Objects support type attribute cache */
|
|
#define Py_TPFLAGS_HAVE_VERSION_TAG (1UL << 18)
|
|
#define Py_TPFLAGS_VALID_VERSION_TAG (1UL << 19)
|
|
|
|
/* Type is abstract and cannot be instantiated */
|
|
#define Py_TPFLAGS_IS_ABSTRACT (1UL << 20)
|
|
|
|
/* These flags are used to determine if a type is a subclass. */
|
|
#define Py_TPFLAGS_LONG_SUBCLASS (1UL << 24)
|
|
#define Py_TPFLAGS_LIST_SUBCLASS (1UL << 25)
|
|
#define Py_TPFLAGS_TUPLE_SUBCLASS (1UL << 26)
|
|
#define Py_TPFLAGS_BYTES_SUBCLASS (1UL << 27)
|
|
#define Py_TPFLAGS_UNICODE_SUBCLASS (1UL << 28)
|
|
#define Py_TPFLAGS_DICT_SUBCLASS (1UL << 29)
|
|
#define Py_TPFLAGS_BASE_EXC_SUBCLASS (1UL << 30)
|
|
#define Py_TPFLAGS_TYPE_SUBCLASS (1UL << 31)
|
|
|
|
#define Py_TPFLAGS_DEFAULT ( \
|
|
Py_TPFLAGS_HAVE_STACKLESS_EXTENSION | \
|
|
Py_TPFLAGS_HAVE_VERSION_TAG | \
|
|
0)
|
|
|
|
/* NOTE: The following flags reuse lower bits (removed as part of the
|
|
* Python 3.0 transition). */
|
|
|
|
/* Type structure has tp_finalize member (3.4) */
|
|
#define Py_TPFLAGS_HAVE_FINALIZE (1UL << 0)
|
|
|
|
#ifdef Py_LIMITED_API
|
|
#define PyType_HasFeature(t,f) ((PyType_GetFlags(t) & (f)) != 0)
|
|
#else
|
|
#define PyType_HasFeature(t,f) (((t)->tp_flags & (f)) != 0)
|
|
#endif
|
|
#define PyType_FastSubclass(t,f) PyType_HasFeature(t,f)
|
|
|
|
|
|
/*
|
|
The macros Py_INCREF(op) and Py_DECREF(op) are used to increment or decrement
|
|
reference counts. Py_DECREF calls the object's deallocator function when
|
|
the refcount falls to 0; for
|
|
objects that don't contain references to other objects or heap memory
|
|
this can be the standard function free(). Both macros can be used
|
|
wherever a void expression is allowed. The argument must not be a
|
|
NULL pointer. If it may be NULL, use Py_XINCREF/Py_XDECREF instead.
|
|
The macro _Py_NewReference(op) initialize reference counts to 1, and
|
|
in special builds (Py_REF_DEBUG, Py_TRACE_REFS) performs additional
|
|
bookkeeping appropriate to the special build.
|
|
|
|
We assume that the reference count field can never overflow; this can
|
|
be proven when the size of the field is the same as the pointer size, so
|
|
we ignore the possibility. Provided a C int is at least 32 bits (which
|
|
is implicitly assumed in many parts of this code), that's enough for
|
|
about 2**31 references to an object.
|
|
|
|
XXX The following became out of date in Python 2.2, but I'm not sure
|
|
XXX what the full truth is now. Certainly, heap-allocated type objects
|
|
XXX can and should be deallocated.
|
|
Type objects should never be deallocated; the type pointer in an object
|
|
is not considered to be a reference to the type object, to save
|
|
complications in the deallocation function. (This is actually a
|
|
decision that's up to the implementer of each new type so if you want,
|
|
you can count such references to the type object.)
|
|
*/
|
|
|
|
/* First define a pile of simple helper macros, one set per special
|
|
* build symbol. These either expand to the obvious things, or to
|
|
* nothing at all when the special mode isn't in effect. The main
|
|
* macros can later be defined just once then, yet expand to different
|
|
* things depending on which special build options are and aren't in effect.
|
|
* Trust me <wink>: while painful, this is 20x easier to understand than,
|
|
* e.g, defining _Py_NewReference five different times in a maze of nested
|
|
* #ifdefs (we used to do that -- it was impenetrable).
|
|
*/
|
|
#ifdef Py_REF_DEBUG
|
|
PyAPI_DATA(Py_ssize_t) _Py_RefTotal;
|
|
PyAPI_FUNC(void) _Py_NegativeRefcount(const char *fname,
|
|
int lineno, PyObject *op);
|
|
PyAPI_FUNC(Py_ssize_t) _Py_GetRefTotal(void);
|
|
#define _Py_INC_REFTOTAL _Py_RefTotal++
|
|
#define _Py_DEC_REFTOTAL _Py_RefTotal--
|
|
#define _Py_REF_DEBUG_COMMA ,
|
|
#define _Py_CHECK_REFCNT(OP) \
|
|
{ if (((PyObject*)OP)->ob_refcnt < 0) \
|
|
_Py_NegativeRefcount(__FILE__, __LINE__, \
|
|
(PyObject *)(OP)); \
|
|
}
|
|
/* Py_REF_DEBUG also controls the display of refcounts and memory block
|
|
* allocations at the interactive prompt and at interpreter shutdown
|
|
*/
|
|
PyAPI_FUNC(void) _PyDebug_PrintTotalRefs(void);
|
|
#else
|
|
#define _Py_INC_REFTOTAL
|
|
#define _Py_DEC_REFTOTAL
|
|
#define _Py_REF_DEBUG_COMMA
|
|
#define _Py_CHECK_REFCNT(OP) /* a semicolon */;
|
|
#endif /* Py_REF_DEBUG */
|
|
|
|
#ifdef COUNT_ALLOCS
|
|
PyAPI_FUNC(void) inc_count(PyTypeObject *);
|
|
PyAPI_FUNC(void) dec_count(PyTypeObject *);
|
|
#define _Py_INC_TPALLOCS(OP) inc_count(Py_TYPE(OP))
|
|
#define _Py_INC_TPFREES(OP) dec_count(Py_TYPE(OP))
|
|
#define _Py_DEC_TPFREES(OP) Py_TYPE(OP)->tp_frees--
|
|
#define _Py_COUNT_ALLOCS_COMMA ,
|
|
#else
|
|
#define _Py_INC_TPALLOCS(OP)
|
|
#define _Py_INC_TPFREES(OP)
|
|
#define _Py_DEC_TPFREES(OP)
|
|
#define _Py_COUNT_ALLOCS_COMMA
|
|
#endif /* COUNT_ALLOCS */
|
|
|
|
#ifdef Py_TRACE_REFS
|
|
/* Py_TRACE_REFS is such major surgery that we call external routines. */
|
|
PyAPI_FUNC(void) _Py_NewReference(PyObject *);
|
|
PyAPI_FUNC(void) _Py_ForgetReference(PyObject *);
|
|
PyAPI_FUNC(void) _Py_Dealloc(PyObject *);
|
|
PyAPI_FUNC(void) _Py_PrintReferences(FILE *);
|
|
PyAPI_FUNC(void) _Py_PrintReferenceAddresses(FILE *);
|
|
PyAPI_FUNC(void) _Py_AddToAllObjects(PyObject *, int force);
|
|
|
|
#else
|
|
/* Without Py_TRACE_REFS, there's little enough to do that we expand code
|
|
* inline.
|
|
*/
|
|
#define _Py_NewReference(op) ( \
|
|
_Py_INC_TPALLOCS(op) _Py_COUNT_ALLOCS_COMMA \
|
|
_Py_INC_REFTOTAL _Py_REF_DEBUG_COMMA \
|
|
Py_REFCNT(op) = 1)
|
|
|
|
#define _Py_ForgetReference(op) _Py_INC_TPFREES(op)
|
|
|
|
#ifdef Py_LIMITED_API
|
|
PyAPI_FUNC(void) _Py_Dealloc(PyObject *);
|
|
#else
|
|
#define _Py_Dealloc(op) ( \
|
|
_Py_INC_TPFREES(op) _Py_COUNT_ALLOCS_COMMA \
|
|
(*Py_TYPE(op)->tp_dealloc)((PyObject *)(op)))
|
|
#endif
|
|
#endif /* !Py_TRACE_REFS */
|
|
|
|
#define Py_INCREF(op) ( \
|
|
_Py_INC_REFTOTAL _Py_REF_DEBUG_COMMA \
|
|
((PyObject *)(op))->ob_refcnt++)
|
|
|
|
#define Py_DECREF(op) \
|
|
do { \
|
|
PyObject *_py_decref_tmp = (PyObject *)(op); \
|
|
if (_Py_DEC_REFTOTAL _Py_REF_DEBUG_COMMA \
|
|
--(_py_decref_tmp)->ob_refcnt != 0) \
|
|
_Py_CHECK_REFCNT(_py_decref_tmp) \
|
|
else \
|
|
_Py_Dealloc(_py_decref_tmp); \
|
|
} while (0)
|
|
|
|
/* Safely decref `op` and set `op` to NULL, especially useful in tp_clear
|
|
* and tp_dealloc implementations.
|
|
*
|
|
* Note that "the obvious" code can be deadly:
|
|
*
|
|
* Py_XDECREF(op);
|
|
* op = NULL;
|
|
*
|
|
* Typically, `op` is something like self->containee, and `self` is done
|
|
* using its `containee` member. In the code sequence above, suppose
|
|
* `containee` is non-NULL with a refcount of 1. Its refcount falls to
|
|
* 0 on the first line, which can trigger an arbitrary amount of code,
|
|
* possibly including finalizers (like __del__ methods or weakref callbacks)
|
|
* coded in Python, which in turn can release the GIL and allow other threads
|
|
* to run, etc. Such code may even invoke methods of `self` again, or cause
|
|
* cyclic gc to trigger, but-- oops! --self->containee still points to the
|
|
* object being torn down, and it may be in an insane state while being torn
|
|
* down. This has in fact been a rich historic source of miserable (rare &
|
|
* hard-to-diagnose) segfaulting (and other) bugs.
|
|
*
|
|
* The safe way is:
|
|
*
|
|
* Py_CLEAR(op);
|
|
*
|
|
* That arranges to set `op` to NULL _before_ decref'ing, so that any code
|
|
* triggered as a side-effect of `op` getting torn down no longer believes
|
|
* `op` points to a valid object.
|
|
*
|
|
* There are cases where it's safe to use the naive code, but they're brittle.
|
|
* For example, if `op` points to a Python integer, you know that destroying
|
|
* one of those can't cause problems -- but in part that relies on that
|
|
* Python integers aren't currently weakly referencable. Best practice is
|
|
* to use Py_CLEAR() even if you can't think of a reason for why you need to.
|
|
*/
|
|
#define Py_CLEAR(op) \
|
|
do { \
|
|
PyObject *_py_tmp = (PyObject *)(op); \
|
|
if (_py_tmp != NULL) { \
|
|
(op) = NULL; \
|
|
Py_DECREF(_py_tmp); \
|
|
} \
|
|
} while (0)
|
|
|
|
/* Macros to use in case the object pointer may be NULL: */
|
|
#define Py_XINCREF(op) \
|
|
do { \
|
|
PyObject *_py_xincref_tmp = (PyObject *)(op); \
|
|
if (_py_xincref_tmp != NULL) \
|
|
Py_INCREF(_py_xincref_tmp); \
|
|
} while (0)
|
|
|
|
#define Py_XDECREF(op) \
|
|
do { \
|
|
PyObject *_py_xdecref_tmp = (PyObject *)(op); \
|
|
if (_py_xdecref_tmp != NULL) \
|
|
Py_DECREF(_py_xdecref_tmp); \
|
|
} while (0)
|
|
|
|
#ifndef Py_LIMITED_API
|
|
/* Safely decref `op` and set `op` to `op2`.
|
|
*
|
|
* As in case of Py_CLEAR "the obvious" code can be deadly:
|
|
*
|
|
* Py_DECREF(op);
|
|
* op = op2;
|
|
*
|
|
* The safe way is:
|
|
*
|
|
* Py_SETREF(op, op2);
|
|
*
|
|
* That arranges to set `op` to `op2` _before_ decref'ing, so that any code
|
|
* triggered as a side-effect of `op` getting torn down no longer believes
|
|
* `op` points to a valid object.
|
|
*
|
|
* Py_XSETREF is a variant of Py_SETREF that uses Py_XDECREF instead of
|
|
* Py_DECREF.
|
|
*/
|
|
|
|
#define Py_SETREF(op, op2) \
|
|
do { \
|
|
PyObject *_py_tmp = (PyObject *)(op); \
|
|
(op) = (op2); \
|
|
Py_DECREF(_py_tmp); \
|
|
} while (0)
|
|
|
|
#define Py_XSETREF(op, op2) \
|
|
do { \
|
|
PyObject *_py_tmp = (PyObject *)(op); \
|
|
(op) = (op2); \
|
|
Py_XDECREF(_py_tmp); \
|
|
} while (0)
|
|
|
|
#endif /* ifndef Py_LIMITED_API */
|
|
|
|
/*
|
|
These are provided as conveniences to Python runtime embedders, so that
|
|
they can have object code that is not dependent on Python compilation flags.
|
|
*/
|
|
PyAPI_FUNC(void) Py_IncRef(PyObject *);
|
|
PyAPI_FUNC(void) Py_DecRef(PyObject *);
|
|
|
|
#ifndef Py_LIMITED_API
|
|
PyAPI_DATA(PyTypeObject) _PyNone_Type;
|
|
PyAPI_DATA(PyTypeObject) _PyNotImplemented_Type;
|
|
#endif /* !Py_LIMITED_API */
|
|
|
|
/*
|
|
_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').
|
|
|
|
Don't forget to apply Py_INCREF() when returning this value!!!
|
|
*/
|
|
PyAPI_DATA(PyObject) _Py_NoneStruct; /* Don't use this directly */
|
|
#define Py_None (&_Py_NoneStruct)
|
|
|
|
/* Macro for returning Py_None from a function */
|
|
#define Py_RETURN_NONE return Py_INCREF(Py_None), Py_None
|
|
|
|
/*
|
|
Py_NotImplemented is a singleton used to signal that an operation is
|
|
not implemented for a given type combination.
|
|
*/
|
|
PyAPI_DATA(PyObject) _Py_NotImplementedStruct; /* Don't use this directly */
|
|
#define Py_NotImplemented (&_Py_NotImplementedStruct)
|
|
|
|
/* Macro for returning Py_NotImplemented from a function */
|
|
#define Py_RETURN_NOTIMPLEMENTED \
|
|
return Py_INCREF(Py_NotImplemented), Py_NotImplemented
|
|
|
|
/* 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
|
|
|
|
/*
|
|
* Macro for implementing rich comparisons
|
|
*
|
|
* Needs to be a macro because any C-comparable type can be used.
|
|
*/
|
|
#define Py_RETURN_RICHCOMPARE(val1, val2, op) \
|
|
do { \
|
|
switch (op) { \
|
|
case Py_EQ: if ((val1) == (val2)) Py_RETURN_TRUE; Py_RETURN_FALSE; \
|
|
case Py_NE: if ((val1) != (val2)) Py_RETURN_TRUE; Py_RETURN_FALSE; \
|
|
case Py_LT: if ((val1) < (val2)) Py_RETURN_TRUE; Py_RETURN_FALSE; \
|
|
case Py_GT: if ((val1) > (val2)) Py_RETURN_TRUE; Py_RETURN_FALSE; \
|
|
case Py_LE: if ((val1) <= (val2)) Py_RETURN_TRUE; Py_RETURN_FALSE; \
|
|
case Py_GE: if ((val1) >= (val2)) Py_RETURN_TRUE; Py_RETURN_FALSE; \
|
|
default: \
|
|
Py_UNREACHABLE(); \
|
|
} \
|
|
} while (0)
|
|
|
|
#ifndef Py_LIMITED_API
|
|
/* Maps Py_LT to Py_GT, ..., Py_GE to Py_LE.
|
|
* Defined in object.c.
|
|
*/
|
|
PyAPI_DATA(int) _Py_SwappedOp[];
|
|
#endif /* !Py_LIMITED_API */
|
|
|
|
|
|
/*
|
|
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. If
|
|
an error was set, the caller must either explicitly clear it, or pass
|
|
the error on to its caller.
|
|
|
|
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().
|
|
Some functions that 'store' objects, such as PyTuple_SetItem() and
|
|
PyList_SetItem(),
|
|
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_SetItem(), consume the reference even if the object wasn't
|
|
successfully 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 mechanism, thanks to Christian Tismer.
|
|
|
|
When deallocating a container object, it's possible to trigger an unbounded
|
|
chain of deallocations, as each Py_DECREF in turn drops the refcount on "the
|
|
next" object in the chain to 0. This can easily lead to stack faults, and
|
|
especially in threads (which typically have less stack space to work with).
|
|
|
|
A container object that participates in cyclic gc can avoid this by
|
|
bracketing the body of its tp_dealloc function with a pair of macros:
|
|
|
|
static void
|
|
mytype_dealloc(mytype *p)
|
|
{
|
|
... declarations go here ...
|
|
|
|
PyObject_GC_UnTrack(p); // must untrack first
|
|
Py_TRASHCAN_SAFE_BEGIN(p)
|
|
... The body of the deallocator goes here, including all calls ...
|
|
... to Py_DECREF on contained objects. ...
|
|
Py_TRASHCAN_SAFE_END(p)
|
|
}
|
|
|
|
CAUTION: Never return from the middle of the body! If the body needs to
|
|
"get out early", put a label immediately before the Py_TRASHCAN_SAFE_END
|
|
call, and goto it. Else the call-depth counter (see below) will stay
|
|
above 0 forever, and the trashcan will never get emptied.
|
|
|
|
How it works: The BEGIN macro increments a call-depth counter. So long
|
|
as this counter is small, the body of the deallocator is run directly without
|
|
further ado. But if the counter gets large, it instead adds p to a list of
|
|
objects to be deallocated later, skips the body of the deallocator, and
|
|
resumes execution after the END macro. The tp_dealloc routine then returns
|
|
without deallocating anything (and so unbounded call-stack depth is avoided).
|
|
|
|
When the call stack finishes unwinding again, code generated by the END macro
|
|
notices this, and calls another routine to deallocate all the objects that
|
|
may have been added to the list of deferred deallocations. In effect, a
|
|
chain of N deallocations is broken into (N-1)/(PyTrash_UNWIND_LEVEL-1) pieces,
|
|
with the call stack never exceeding a depth of PyTrash_UNWIND_LEVEL.
|
|
*/
|
|
|
|
#ifndef Py_LIMITED_API
|
|
/* This is the old private API, invoked by the macros before 3.2.4.
|
|
Kept for binary compatibility of extensions using the stable ABI. */
|
|
PyAPI_FUNC(void) _PyTrash_deposit_object(PyObject*);
|
|
PyAPI_FUNC(void) _PyTrash_destroy_chain(void);
|
|
#endif /* !Py_LIMITED_API */
|
|
|
|
/* The new thread-safe private API, invoked by the macros below. */
|
|
PyAPI_FUNC(void) _PyTrash_thread_deposit_object(PyObject*);
|
|
PyAPI_FUNC(void) _PyTrash_thread_destroy_chain(void);
|
|
|
|
#define PyTrash_UNWIND_LEVEL 50
|
|
|
|
#define Py_TRASHCAN_SAFE_BEGIN(op) \
|
|
do { \
|
|
PyThreadState *_tstate = PyThreadState_GET(); \
|
|
if (_tstate->trash_delete_nesting < PyTrash_UNWIND_LEVEL) { \
|
|
++_tstate->trash_delete_nesting;
|
|
/* The body of the deallocator is here. */
|
|
#define Py_TRASHCAN_SAFE_END(op) \
|
|
--_tstate->trash_delete_nesting; \
|
|
if (_tstate->trash_delete_later && _tstate->trash_delete_nesting <= 0) \
|
|
_PyTrash_thread_destroy_chain(); \
|
|
} \
|
|
else \
|
|
_PyTrash_thread_deposit_object((PyObject*)op); \
|
|
} while (0);
|
|
|
|
#ifndef Py_LIMITED_API
|
|
PyAPI_FUNC(void)
|
|
_PyDebugAllocatorStats(FILE *out, const char *block_name, int num_blocks,
|
|
size_t sizeof_block);
|
|
PyAPI_FUNC(void)
|
|
_PyObject_DebugTypeStats(FILE *out);
|
|
#endif /* ifndef Py_LIMITED_API */
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
#endif /* !Py_OBJECT_H */
|