https://github.com/python/cpython
Tip revision: 1da43e5e916949c8e849e656d9d05fa4b9d6836c authored by Benjamin Peterson on 26 June 2009, 13:21:52 UTC
rearrange the sections of the README, so they'll hopefully be more in the order people will interested in
rearrange the sections of the README, so they'll hopefully be more in the order people will interested in
Tip revision: 1da43e5
atexitmodule.c
/*
* atexit - allow programmer to define multiple exit functions to be executed
* upon normal program termination.
*
* Translated from atexit.py by Collin Winter.
+ Copyright 2007 Python Software Foundation.
*/
#include "Python.h"
/* Forward declaration (for atexit_cleanup) */
static PyObject *atexit_clear(PyObject*, PyObject*);
/* Forward declaration (for atexit_callfuncs) */
static void atexit_cleanup(PyObject*);
/* Forward declaration of module object */
static struct PyModuleDef atexitmodule;
/* ===================================================================== */
/* Callback machinery. */
typedef struct {
PyObject *func;
PyObject *args;
PyObject *kwargs;
} atexit_callback;
typedef struct {
atexit_callback **atexit_callbacks;
int ncallbacks;
int callback_len;
} atexitmodule_state;
#define GET_ATEXIT_STATE(mod) ((atexitmodule_state*)PyModule_GetState(mod))
/* Installed into pythonrun.c's atexit mechanism */
static void
atexit_callfuncs(void)
{
PyObject *exc_type = NULL, *exc_value, *exc_tb, *r;
atexit_callback *cb;
PyObject *module;
atexitmodule_state *modstate;
int i;
module = PyState_FindModule(&atexitmodule);
if (module == NULL)
return;
modstate = GET_ATEXIT_STATE(module);
if (modstate->ncallbacks == 0)
return;
for (i = modstate->ncallbacks - 1; i >= 0; i--)
{
cb = modstate->atexit_callbacks[i];
if (cb == NULL)
continue;
r = PyObject_Call(cb->func, cb->args, cb->kwargs);
Py_XDECREF(r);
if (r == NULL) {
/* Maintain the last exception, but don't leak if there are
multiple exceptions. */
if (exc_type) {
Py_DECREF(exc_type);
Py_XDECREF(exc_value);
Py_XDECREF(exc_tb);
}
PyErr_Fetch(&exc_type, &exc_value, &exc_tb);
if (!PyErr_ExceptionMatches(PyExc_SystemExit)) {
PySys_WriteStderr("Error in atexit._run_exitfuncs:\n");
PyErr_Display(exc_type, exc_value, exc_tb);
}
}
}
atexit_cleanup(module);
if (exc_type)
PyErr_Restore(exc_type, exc_value, exc_tb);
}
static void
atexit_delete_cb(PyObject *self, int i)
{
atexitmodule_state *modstate;
atexit_callback *cb;
modstate = GET_ATEXIT_STATE(self);
cb = modstate->atexit_callbacks[i];
modstate->atexit_callbacks[i] = NULL;
Py_DECREF(cb->func);
Py_DECREF(cb->args);
Py_XDECREF(cb->kwargs);
PyMem_Free(cb);
}
static void
atexit_cleanup(PyObject *self)
{
PyObject *r = atexit_clear(self, NULL);
Py_DECREF(r);
}
/* ===================================================================== */
/* Module methods. */
PyDoc_STRVAR(atexit_register__doc__,
"register(func, *args, **kwargs) -> func\n\
\n\
Register a function to be executed upon normal program termination\n\
\n\
func - function to be called at exit\n\
args - optional arguments to pass to func\n\
kwargs - optional keyword arguments to pass to func\n\
\n\
func is returned to facilitate usage as a decorator.");
static PyObject *
atexit_register(PyObject *self, PyObject *args, PyObject *kwargs)
{
atexitmodule_state *modstate;
atexit_callback *new_callback;
PyObject *func = NULL;
modstate = GET_ATEXIT_STATE(self);
if (modstate->ncallbacks >= modstate->callback_len) {
atexit_callback **r;
modstate->callback_len += 16;
r = (atexit_callback**)PyMem_Realloc(modstate->atexit_callbacks,
sizeof(atexit_callback*) * modstate->callback_len);
if (r == NULL)
return PyErr_NoMemory();
modstate->atexit_callbacks = r;
}
if (PyTuple_GET_SIZE(args) == 0) {
PyErr_SetString(PyExc_TypeError,
"register() takes at least 1 argument (0 given)");
return NULL;
}
func = PyTuple_GET_ITEM(args, 0);
if (!PyCallable_Check(func)) {
PyErr_SetString(PyExc_TypeError,
"the first argument must be callable");
return NULL;
}
new_callback = PyMem_Malloc(sizeof(atexit_callback));
if (new_callback == NULL)
return PyErr_NoMemory();
new_callback->args = PyTuple_GetSlice(args, 1, PyTuple_GET_SIZE(args));
if (new_callback->args == NULL) {
PyMem_Free(new_callback);
return NULL;
}
new_callback->func = func;
new_callback->kwargs = kwargs;
Py_INCREF(func);
Py_XINCREF(kwargs);
modstate->atexit_callbacks[modstate->ncallbacks++] = new_callback;
Py_INCREF(func);
return func;
}
PyDoc_STRVAR(atexit_run_exitfuncs__doc__,
"_run_exitfuncs() -> None\n\
\n\
Run all registered exit functions.");
static PyObject *
atexit_run_exitfuncs(PyObject *self, PyObject *unused)
{
atexit_callfuncs();
if (PyErr_Occurred())
return NULL;
Py_RETURN_NONE;
}
PyDoc_STRVAR(atexit_clear__doc__,
"_clear() -> None\n\
\n\
Clear the list of previously registered exit functions.");
static PyObject *
atexit_clear(PyObject *self, PyObject *unused)
{
atexitmodule_state *modstate;
atexit_callback *cb;
int i;
modstate = GET_ATEXIT_STATE(self);
for (i = 0; i < modstate->ncallbacks; i++) {
cb = modstate->atexit_callbacks[i];
if (cb == NULL)
continue;
atexit_delete_cb(self, i);
}
modstate->ncallbacks = 0;
Py_RETURN_NONE;
}
PyDoc_STRVAR(atexit_unregister__doc__,
"unregister(func) -> None\n\
\n\
Unregister a exit function which was previously registered using\n\
atexit.register\n\
\n\
func - function to be unregistered");
static PyObject *
atexit_unregister(PyObject *self, PyObject *func)
{
atexitmodule_state *modstate;
atexit_callback *cb;
int i, eq;
modstate = GET_ATEXIT_STATE(self);
for (i = 0; i < modstate->ncallbacks; i++)
{
cb = modstate->atexit_callbacks[i];
if (cb == NULL)
continue;
eq = PyObject_RichCompareBool(cb->func, func, Py_EQ);
if (eq < 0)
return NULL;
if (eq)
atexit_delete_cb(self, i);
}
Py_RETURN_NONE;
}
static PyMethodDef atexit_methods[] = {
{"register", (PyCFunction) atexit_register, METH_VARARGS|METH_KEYWORDS,
atexit_register__doc__},
{"_clear", (PyCFunction) atexit_clear, METH_NOARGS,
atexit_clear__doc__},
{"unregister", (PyCFunction) atexit_unregister, METH_O,
atexit_unregister__doc__},
{"_run_exitfuncs", (PyCFunction) atexit_run_exitfuncs, METH_NOARGS,
atexit_run_exitfuncs__doc__},
{NULL, NULL} /* sentinel */
};
/* ===================================================================== */
/* Initialization function. */
PyDoc_STRVAR(atexit__doc__,
"allow programmer to define multiple exit functions to be executed\
upon normal program termination.\n\
\n\
Two public functions, register and unregister, are defined.\n\
");
static struct PyModuleDef atexitmodule = {
PyModuleDef_HEAD_INIT,
"atexit",
atexit__doc__,
sizeof(atexitmodule_state),
atexit_methods,
NULL,
NULL,
NULL,
NULL
};
PyMODINIT_FUNC
PyInit_atexit(void)
{
PyObject *m;
atexitmodule_state *modstate;
m = PyModule_Create(&atexitmodule);
if (m == NULL)
return NULL;
modstate = GET_ATEXIT_STATE(m);
modstate->callback_len = 32;
modstate->ncallbacks = 0;
modstate->atexit_callbacks = PyMem_New(atexit_callback*,
modstate->callback_len);
if (modstate->atexit_callbacks == NULL)
return NULL;
_Py_PyAtExit(atexit_callfuncs);
return m;
}