Skip to content

bpo-38075: Port _randommodule.c to PEP-384 #15798

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 3 commits into from
Sep 13, 2019
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 @@
The random module is now PEP-384 compatible
149 changes: 92 additions & 57 deletions Modules/_randommodule.c
Original file line number Diff line number Diff line change
Expand Up @@ -79,15 +79,23 @@
#define UPPER_MASK 0x80000000U /* most significant w-r bits */
#define LOWER_MASK 0x7fffffffU /* least significant r bits */

typedef struct {
PyObject *Random_Type;
PyObject *Long___abs__;
} _randomstate;

#define _randomstate(o) ((_randomstate *)PyModule_GetState(o))

static struct PyModuleDef _randommodule;

#define _randomstate_global _randomstate(PyState_FindModule(&_randommodule))

typedef struct {
PyObject_HEAD
int index;
uint32_t state[N];
} RandomObject;

static PyTypeObject Random_Type;

#define RandomObject_Check(v) (Py_TYPE(v) == &Random_Type)

#include "clinic/_randommodule.c.h"

Expand Down Expand Up @@ -256,6 +264,7 @@ random_seed(RandomObject *self, PyObject *arg)
uint32_t *key = NULL;
size_t bits, keyused;
int res;
PyObject *args[1];

if (arg == NULL || arg == Py_None) {
if (random_seed_urandom(self) < 0) {
Expand All @@ -272,10 +281,14 @@ random_seed(RandomObject *self, PyObject *arg)
* So: if the arg is a PyLong, use its absolute value.
* Otherwise use its hash value, cast to unsigned.
*/
if (PyLong_Check(arg)) {
if (PyLong_CheckExact(arg)) {
n = PyNumber_Absolute(arg);
} else if (PyLong_Check(arg)) {
/* Calling int.__abs__() prevents calling arg.__abs__(), which might
return an invalid value. See issue #31478. */
n = PyLong_Type.tp_as_number->nb_absolute(arg);
args[0] = arg;
n = _PyObject_Vectorcall(_randomstate_global->Long___abs__, args, 0,
NULL);
}
else {
Py_hash_t hash = PyObject_Hash(arg);
Expand Down Expand Up @@ -500,10 +513,12 @@ random_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
RandomObject *self;
PyObject *tmp;

if (type == &Random_Type && !_PyArg_NoKeywords("Random", kwds))
if (type == (PyTypeObject*)_randomstate_global->Random_Type &&
!_PyArg_NoKeywords("Random()", kwds)) {
return NULL;
}

self = (RandomObject *)type->tp_alloc(type, 0);
self = (RandomObject *)PyType_GenericAlloc(type, 0);
if (self == NULL)
return NULL;
tmp = random_seed(self, args);
Expand All @@ -527,77 +542,97 @@ static PyMethodDef random_methods[] = {
PyDoc_STRVAR(random_doc,
"Random() -> create a random number generator with its own internal state.");

static PyTypeObject Random_Type = {
PyVarObject_HEAD_INIT(NULL, 0)
"_random.Random", /*tp_name*/
sizeof(RandomObject), /*tp_basicsize*/
0, /*tp_itemsize*/
/* methods */
0, /*tp_dealloc*/
0, /*tp_vectorcall_offset*/
0, /*tp_getattr*/
0, /*tp_setattr*/
0, /*tp_as_async*/
0, /*tp_repr*/
0, /*tp_as_number*/
0, /*tp_as_sequence*/
0, /*tp_as_mapping*/
0, /*tp_hash*/
0, /*tp_call*/
0, /*tp_str*/
PyObject_GenericGetAttr, /*tp_getattro*/
0, /*tp_setattro*/
0, /*tp_as_buffer*/
Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /*tp_flags*/
random_doc, /*tp_doc*/
0, /*tp_traverse*/
0, /*tp_clear*/
0, /*tp_richcompare*/
0, /*tp_weaklistoffset*/
0, /*tp_iter*/
0, /*tp_iternext*/
random_methods, /*tp_methods*/
0, /*tp_members*/
0, /*tp_getset*/
0, /*tp_base*/
0, /*tp_dict*/
0, /*tp_descr_get*/
0, /*tp_descr_set*/
0, /*tp_dictoffset*/
0, /*tp_init*/
0, /*tp_alloc*/
random_new, /*tp_new*/
PyObject_Free, /*tp_free*/
0, /*tp_is_gc*/
static PyType_Slot Random_Type_slots[] = {
{Py_tp_doc, random_doc},
{Py_tp_methods, random_methods},
{Py_tp_new, random_new},
{Py_tp_free, PyObject_Free},
{0, 0},
};

static PyType_Spec Random_Type_spec = {
"_random.Random",
sizeof(RandomObject),
0,
Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE,
Random_Type_slots
};

PyDoc_STRVAR(module_doc,
"Module implements the Mersenne Twister random number generator.");

static int
_random_traverse(PyObject *module, visitproc visit, void *arg)
{
Py_VISIT(_randomstate(module)->Random_Type);
return 0;
}

static int
_random_clear(PyObject *module)
{
Py_CLEAR(_randomstate(module)->Random_Type);
return 0;
}

static void
_random_free(void *module)
{
_random_clear((PyObject *)module);
}

static struct PyModuleDef _randommodule = {
PyModuleDef_HEAD_INIT,
"_random",
module_doc,
-1,
NULL,
sizeof(_randomstate),
NULL,
NULL,
NULL,
NULL
_random_traverse,
_random_clear,
_random_free,
};

PyMODINIT_FUNC
PyInit__random(void)
{
PyObject *m;

if (PyType_Ready(&Random_Type) < 0)
PyObject *Random_Type = PyType_FromSpec(&Random_Type_spec);
if (Random_Type == NULL) {
return NULL;
}

m = PyModule_Create(&_randommodule);
if (m == NULL)
if (m == NULL) {
Py_DECREF(Random_Type);
return NULL;
Py_INCREF(&Random_Type);
PyModule_AddObject(m, "Random", (PyObject *)&Random_Type);
}
_randomstate(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);
_randomstate(m)->Long___abs__ = abs;

return m;

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