1 #ifndef Py_INTERNAL_OBJECT_H
2 #define Py_INTERNAL_OBJECT_H
3 #ifdef __cplusplus
4 extern "C" {
5 #endif
6
7 #ifndef Py_BUILD_CORE
8 # error "this header requires Py_BUILD_CORE define"
9 #endif
10
11 #include "pycore_gc.h" // _PyObject_GC_IS_TRACKED()
12 #include "pycore_interp.h" // PyInterpreterState.gc
13 #include "pycore_pystate.h" // _PyInterpreterState_GET()
14
15 PyAPI_FUNC(int) _PyType_CheckConsistency(PyTypeObject *type);
16 PyAPI_FUNC(int) _PyDict_CheckConsistency(PyObject *mp, int check_content);
17
18 /* Update the Python traceback of an object. This function must be called
19 when a memory block is reused from a free list.
20
21 Internal function called by _Py_NewReference(). */
22 extern int _PyTraceMalloc_NewReference(PyObject *op);
23
24 // Fast inlined version of PyType_HasFeature()
25 static inline int
_PyType_HasFeature(PyTypeObject * type,unsigned long feature)26 _PyType_HasFeature(PyTypeObject *type, unsigned long feature) {
27 return ((type->tp_flags & feature) != 0);
28 }
29
30 extern void _PyType_InitCache(PyInterpreterState *interp);
31
32 /* Only private in Python 3.10 and 3.9.8+; public in 3.11 */
33 extern PyObject *_PyType_GetQualName(PyTypeObject *type);
34
35 /* Inline functions trading binary compatibility for speed:
36 _PyObject_Init() is the fast version of PyObject_Init(), and
37 _PyObject_InitVar() is the fast version of PyObject_InitVar().
38
39 These inline functions must not be called with op=NULL. */
40 static inline void
_PyObject_Init(PyObject * op,PyTypeObject * typeobj)41 _PyObject_Init(PyObject *op, PyTypeObject *typeobj)
42 {
43 assert(op != NULL);
44 Py_SET_TYPE(op, typeobj);
45 if (_PyType_HasFeature(typeobj, Py_TPFLAGS_HEAPTYPE)) {
46 Py_INCREF(typeobj);
47 }
48 _Py_NewReference(op);
49 }
50
51 static inline void
_PyObject_InitVar(PyVarObject * op,PyTypeObject * typeobj,Py_ssize_t size)52 _PyObject_InitVar(PyVarObject *op, PyTypeObject *typeobj, Py_ssize_t size)
53 {
54 assert(op != NULL);
55 Py_SET_SIZE(op, size);
56 _PyObject_Init((PyObject *)op, typeobj);
57 }
58
59
60 /* Tell the GC to track this object.
61 *
62 * The object must not be tracked by the GC.
63 *
64 * NB: While the object is tracked by the collector, it must be safe to call the
65 * ob_traverse method.
66 *
67 * Internal note: interp->gc.generation0->_gc_prev doesn't have any bit flags
68 * because it's not object header. So we don't use _PyGCHead_PREV() and
69 * _PyGCHead_SET_PREV() for it to avoid unnecessary bitwise operations.
70 *
71 * See also the public PyObject_GC_Track() function.
72 */
_PyObject_GC_TRACK(const char * filename,int lineno,PyObject * op)73 static inline void _PyObject_GC_TRACK(
74 // The preprocessor removes _PyObject_ASSERT_FROM() calls if NDEBUG is defined
75 #ifndef NDEBUG
76 const char *filename, int lineno,
77 #endif
78 PyObject *op)
79 {
80 _PyObject_ASSERT_FROM(op, !_PyObject_GC_IS_TRACKED(op),
81 "object already tracked by the garbage collector",
82 filename, lineno, __func__);
83
84 PyGC_Head *gc = _Py_AS_GC(op);
85 _PyObject_ASSERT_FROM(op,
86 (gc->_gc_prev & _PyGC_PREV_MASK_COLLECTING) == 0,
87 "object is in generation which is garbage collected",
88 filename, lineno, __func__);
89
90 PyInterpreterState *interp = _PyInterpreterState_GET();
91 PyGC_Head *generation0 = interp->gc.generation0;
92 PyGC_Head *last = (PyGC_Head*)(generation0->_gc_prev);
93 _PyGCHead_SET_NEXT(last, gc);
94 _PyGCHead_SET_PREV(gc, last);
95 _PyGCHead_SET_NEXT(gc, generation0);
96 generation0->_gc_prev = (uintptr_t)gc;
97 }
98
99 /* Tell the GC to stop tracking this object.
100 *
101 * Internal note: This may be called while GC. So _PyGC_PREV_MASK_COLLECTING
102 * must be cleared. But _PyGC_PREV_MASK_FINALIZED bit is kept.
103 *
104 * The object must be tracked by the GC.
105 *
106 * See also the public PyObject_GC_UnTrack() which accept an object which is
107 * not tracked.
108 */
_PyObject_GC_UNTRACK(const char * filename,int lineno,PyObject * op)109 static inline void _PyObject_GC_UNTRACK(
110 // The preprocessor removes _PyObject_ASSERT_FROM() calls if NDEBUG is defined
111 #ifndef NDEBUG
112 const char *filename, int lineno,
113 #endif
114 PyObject *op)
115 {
116 _PyObject_ASSERT_FROM(op, _PyObject_GC_IS_TRACKED(op),
117 "object not tracked by the garbage collector",
118 filename, lineno, __func__);
119
120 PyGC_Head *gc = _Py_AS_GC(op);
121 PyGC_Head *prev = _PyGCHead_PREV(gc);
122 PyGC_Head *next = _PyGCHead_NEXT(gc);
123 _PyGCHead_SET_NEXT(prev, next);
124 _PyGCHead_SET_PREV(next, prev);
125 gc->_gc_next = 0;
126 gc->_gc_prev &= _PyGC_PREV_MASK_FINALIZED;
127 }
128
129 // Macros to accept any type for the parameter, and to automatically pass
130 // the filename and the filename (if NDEBUG is not defined) where the macro
131 // is called.
132 #ifdef NDEBUG
133 # define _PyObject_GC_TRACK(op) \
134 _PyObject_GC_TRACK(_PyObject_CAST(op))
135 # define _PyObject_GC_UNTRACK(op) \
136 _PyObject_GC_UNTRACK(_PyObject_CAST(op))
137 #else
138 # define _PyObject_GC_TRACK(op) \
139 _PyObject_GC_TRACK(__FILE__, __LINE__, _PyObject_CAST(op))
140 # define _PyObject_GC_UNTRACK(op) \
141 _PyObject_GC_UNTRACK(__FILE__, __LINE__, _PyObject_CAST(op))
142 #endif
143
144 #ifdef Py_REF_DEBUG
145 extern void _PyDebug_PrintTotalRefs(void);
146 #endif
147
148 #ifdef Py_TRACE_REFS
149 extern void _Py_AddToAllObjects(PyObject *op, int force);
150 extern void _Py_PrintReferences(FILE *);
151 extern void _Py_PrintReferenceAddresses(FILE *);
152 #endif
153
154 static inline PyObject **
_PyObject_GET_WEAKREFS_LISTPTR(PyObject * op)155 _PyObject_GET_WEAKREFS_LISTPTR(PyObject *op)
156 {
157 Py_ssize_t offset = Py_TYPE(op)->tp_weaklistoffset;
158 return (PyObject **)((char *)op + offset);
159 }
160
161 // Fast inlined version of PyObject_IS_GC()
162 static inline int
_PyObject_IS_GC(PyObject * obj)163 _PyObject_IS_GC(PyObject *obj)
164 {
165 return (PyType_IS_GC(Py_TYPE(obj))
166 && (Py_TYPE(obj)->tp_is_gc == NULL
167 || Py_TYPE(obj)->tp_is_gc(obj)));
168 }
169
170 // Fast inlined version of PyType_IS_GC()
171 #define _PyType_IS_GC(t) _PyType_HasFeature((t), Py_TPFLAGS_HAVE_GC)
172
173 // Usage: assert(_Py_CheckSlotResult(obj, "__getitem__", result != NULL));
174 extern int _Py_CheckSlotResult(
175 PyObject *obj,
176 const char *slot_name,
177 int success);
178
179 // PyType_Ready() must be called if _PyType_IsReady() is false.
180 // See also the Py_TPFLAGS_READY flag.
181 #define _PyType_IsReady(type) ((type)->tp_dict != NULL)
182
183 #ifdef __cplusplus
184 }
185 #endif
186 #endif /* !Py_INTERNAL_OBJECT_H */
187