在我的程序中,我管理C中对
python对象的引用.即我所有的类都是从引用类派生的,它包含指向相应python对象的指针.
class Referenced
{
public:
unsigned use_count() const
{
return selfptr->ob_refcnt;
}
void add_ref() const
{
Py_INCREF(selfptr);
}
void remove_ref() const
{
Py_DECREF(selfptr);
}
PyObject* selfptr;
};
我使用intrusive_ptr来保存从引用导出的对象.这允许我很容易地保留对C中所需的python对象的引用,并访问它们,无论是否需要.但是,当python对象从C被删除时,即当我调用Py_DECREF(selfptr)时,我的程序是否崩溃(只有在Windows中),无论是selfptr-> ob_refcnt == 1.
更新：我终于想到了我的程序中的问题.它与对象删除没有直接关系.要检查初始问题,我已经实现了简单的扩展模块,记住对python对象的引用,并按需释放它.就这个：
#include <Python.h>
static PyObject* myObj;
static PyObject* acquirePythonObject(PyObject* self,PyObject* obj)
{
printf("trying to acquire python object %p,refcount = %d\n",obj,obj->ob_refcnt);
myObj = obj;
Py_INCREF(myObj);
printf("reference acquired\n");
return Py_True;
}
static PyObject* freePythonObject(PyObject*,PyObject*)
{
printf("trying to free python object %p,myObj,myObj->ob_refcnt);
Py_DECREF(myObj);
printf("reference removed\n");
return Py_True;
}
static PyMethodDef moduleMethods[] =
{
{"acquirePythonObject",acquirePythonObject,METH_O,"hold reference to python object."},{"freePythonObject",freePythonObject,METH_NOARGS,"free reference to python object."},{NULL,NULL,NULL}
};
PyMODINIT_FUNC initmodule(void)
{
Py_InitModule("module",moduleMethods);
}
和python脚本：
import module
class Foo:
def __init__(self):
print "Foo is created"
def __deinit__(self):
print "Foo is destroyed"
def acquireFoo():
foo = Foo()
module.acquirePythonObject(foo)
def freeFoo():
module.freePythonObject()
if __name__ == "__main__":
acquireFoo()
freeFoo()
样例在windows和linux中无缝运行.下面是输出.
Foo is created trying to acquire python object 0x7fa19fbefd40,refcount = 2 reference acquired trying to free python object 0x7fa19fbefd40,refcount = 1 Foo is destoryed reference removed
