Skip to content

bpo-1635741: Port _random to multiphase initialization #23359

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Nov 19, 2020
Merged
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
Original file line number Diff line number Diff line change
@@ -0,0 +1 @@
Port _random extension module to multiphase initialization (:pep:`489`)
94 changes: 49 additions & 45 deletions Modules/_randommodule.c
Original file line number Diff line number Diff line change
Expand Up @@ -93,7 +93,8 @@ get_random_state(PyObject *module)

static struct PyModuleDef _randommodule;

#define _randomstate_global get_random_state(PyState_FindModule(&_randommodule))
#define _randomstate_type(type) \
(get_random_state(_PyType_GetModuleByDef(type, &_randommodule)))

typedef struct {
PyObject_HEAD
Expand All @@ -106,9 +107,9 @@ typedef struct {

/*[clinic input]
module _random
class _random.Random "RandomObject *" "&Random_Type"
class _random.Random "RandomObject *" "_randomstate_type(type)->Random_Type"
[clinic start generated code]*/
/*[clinic end generated code: output=da39a3ee5e6b4b0d input=f79898ae7847c321]*/
/*[clinic end generated code: output=da39a3ee5e6b4b0d input=70a2c99619474983]*/

/* Random methods */

Expand Down Expand Up @@ -290,7 +291,8 @@ random_seed(RandomObject *self, PyObject *arg)
} else if (PyLong_Check(arg)) {
/* Calling int.__abs__() prevents calling arg.__abs__(), which might
return an invalid value. See issue #31478. */
n = PyObject_CallOneArg(_randomstate_global->Long___abs__, arg);
_randomstate *state = _randomstate_type(Py_TYPE(self));
n = PyObject_CallOneArg(state->Long___abs__, arg);
}
else {
Py_hash_t hash = PyObject_Hash(arg);
Expand Down Expand Up @@ -517,8 +519,9 @@ random_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
{
RandomObject *self;
PyObject *tmp;
_randomstate *state = _randomstate_type(type);

if (type == (PyTypeObject*)_randomstate_global->Random_Type &&
if (type == (PyTypeObject*)state->Random_Type &&
!_PyArg_NoKeywords("Random()", kwds)) {
return NULL;
}
Expand Down Expand Up @@ -567,6 +570,45 @@ static PyType_Spec Random_Type_spec = {
PyDoc_STRVAR(module_doc,
"Module implements the Mersenne Twister random number generator.");

static int
_random_exec(PyObject *module)
{
_randomstate *state = get_random_state(module);

state->Random_Type = PyType_FromModuleAndSpec(
module, &Random_Type_spec, NULL);
if (state->Random_Type == NULL) {
return -1;
}
if (PyModule_AddType(module, (PyTypeObject *)state->Random_Type) < 0) {
return -1;
}

/* Look up and save int.__abs__, which is needed in random_seed(). */
PyObject *longval = longval = PyLong_FromLong(0);
if (longval == NULL) {
return -1;
}

PyObject *longtype = PyObject_Type(longval);
Py_DECREF(longval);
if (longtype == NULL) {
return -1;
}

state->Long___abs__ = PyObject_GetAttrString(longtype, "__abs__");
Py_DECREF(longtype);
if (state->Long___abs__ == NULL) {
return -1;
}
return 0;
}

static PyModuleDef_Slot _random_slots[] = {
{Py_mod_exec, _random_exec},
{0, NULL}
};

static int
_random_traverse(PyObject *module, visitproc visit, void *arg)
{
Expand Down Expand Up @@ -594,7 +636,7 @@ static struct PyModuleDef _randommodule = {
module_doc,
sizeof(_randomstate),
NULL,
NULL,
_random_slots,
_random_traverse,
_random_clear,
_random_free,
Expand All @@ -603,43 +645,5 @@ static struct PyModuleDef _randommodule = {
PyMODINIT_FUNC
PyInit__random(void)
{
PyObject *m;

PyObject *Random_Type = PyType_FromSpec(&Random_Type_spec);
if (Random_Type == NULL) {
return NULL;
}

m = PyModule_Create(&_randommodule);
if (m == NULL) {
Py_DECREF(Random_Type);
return NULL;
}
get_random_state(m)->Random_Type = Random_Type;

Py_INCREF(Random_Type);
PyModule_AddObject(m, "Random", Random_Type);

/* Look up and save int.__abs__, which is needed in random_seed(). */
PyObject *longval = NULL, *longtype = NULL;
longval = PyLong_FromLong(0);
if (longval == NULL) goto fail;

longtype = PyObject_Type(longval);
if (longtype == NULL) goto fail;

PyObject *abs = PyObject_GetAttrString(longtype, "__abs__");
if (abs == NULL) goto fail;

Py_DECREF(longtype);
Py_DECREF(longval);
get_random_state(m)->Long___abs__ = abs;

return m;

fail:
Py_XDECREF(longtype);
Py_XDECREF(longval);
Py_DECREF(m);
return NULL;
return PyModuleDef_Init(&_randommodule);
}