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		ead8b7ab30
		
	
	
	
	
		
			
			In cyclic gc, clear weakrefs to unreachable objects before allowing any Python code (weakref callbacks or __del__ methods) to run. This is a critical bugfix, affecting all versions of Python since weakrefs were introduced. I'll backport to 2.3.
		
			
				
	
	
		
			75 lines
		
	
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			75 lines
		
	
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* Weak references objects for Python. */
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| 
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| #ifndef Py_WEAKREFOBJECT_H
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| #define Py_WEAKREFOBJECT_H
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| #ifdef __cplusplus
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| extern "C" {
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| #endif
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| 
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| 
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| typedef struct _PyWeakReference PyWeakReference;
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| 
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| /* PyWeakReference is the base struct for the Python ReferenceType, ProxyType,
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|  * and CallableProxyType.
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|  */
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| struct _PyWeakReference {
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|     PyObject_HEAD
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| 
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|     /* The object to which this is a weak reference, or Py_None if none.
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|      * Note that this is a stealth reference:  wr_object's refcount is
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|      * not incremented to reflect this pointer.
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|      */
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|     PyObject *wr_object;
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| 
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|     /* A callable to invoke when wr_object dies, or NULL if none. */
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|     PyObject *wr_callback;
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| 
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|     /* A cache for wr_object's hash code.  As usual for hashes, this is -1
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|      * if the hash code isn't known yet.
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|      */
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|     long hash;
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| 
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|     /* If wr_object is weakly referenced, wr_object has a doubly-linked NULL-
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|      * terminated list of weak references to it.  These are the list pointers.
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|      * If wr_object goes away, wr_object is set to Py_None, and these pointers
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|      * have no meaning then.
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|      */
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|     PyWeakReference *wr_prev;
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|     PyWeakReference *wr_next;
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| };
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| 
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| PyAPI_DATA(PyTypeObject) _PyWeakref_RefType;
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| PyAPI_DATA(PyTypeObject) _PyWeakref_ProxyType;
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| PyAPI_DATA(PyTypeObject) _PyWeakref_CallableProxyType;
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| 
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| #define PyWeakref_CheckRef(op) PyObject_TypeCheck(op, &_PyWeakref_RefType)
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| #define PyWeakref_CheckRefExact(op) \
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|         ((op)->ob_type == &_PyWeakref_RefType)
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| #define PyWeakref_CheckProxy(op) \
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|         (((op)->ob_type == &_PyWeakref_ProxyType) || \
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|          ((op)->ob_type == &_PyWeakref_CallableProxyType))
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| 
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| /* This macro calls PyWeakref_CheckRef() last since that can involve a
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|    function call; this makes it more likely that the function call
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|    will be avoided. */
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| #define PyWeakref_Check(op) \
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|         (PyWeakref_CheckRef(op) || PyWeakref_CheckProxy(op))
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| 
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| 
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| PyAPI_FUNC(PyObject *) PyWeakref_NewRef(PyObject *ob,
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|                                               PyObject *callback);
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| PyAPI_FUNC(PyObject *) PyWeakref_NewProxy(PyObject *ob,
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|                                                 PyObject *callback);
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| PyAPI_FUNC(PyObject *) PyWeakref_GetObject(PyObject *ref);
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| 
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| PyAPI_FUNC(long) _PyWeakref_GetWeakrefCount(PyWeakReference *head);
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| 
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| PyAPI_FUNC(void) _PyWeakref_ClearRef(PyWeakReference *self);
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| 
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| #define PyWeakref_GET_OBJECT(ref) (((PyWeakReference *)(ref))->wr_object)
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| 
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| 
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| #ifdef __cplusplus
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| }
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| #endif
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| #endif /* !Py_WEAKREFOBJECT_H */
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