bpo-1635741: Port hashlib modules to multiphase init (PEP 489)

Misc/NEWS.d/next/Core and Builtins/2020-08-10-16-11-32.bpo-1635741.O0d3ym.rst

@@ -0,0 +1,2 @@
+Port the :mod:`_sha1`, :mod:`_sha512`, and :mod:`_md5` extension modules
+to multi-phase initialization API (:pep:`489`).

Modules/md5module.c

@@ -318,22 +318,32 @@ md5_done(struct md5_state *md5, unsigned char *out)
  * ------------------------------------------------------------------------
  */
 
-static PyTypeObject MD5type;
+typedef struct{
+ PyTypeObject* md5_type;
+} MD5State;
 
+static inline MD5State*
+md5_get_state(PyObject *module)
+{
+ void *state = PyModule_GetState(module);
+ assert(state != NULL);
+ return (MD5State *)state;
+}
 
 static MD5object *
-newMD5object(void)
+newMD5object(MD5State * st)
 {
- return (MD5object *)PyObject_New(MD5object, &MD5type);
+ return (MD5object *)PyObject_New(MD5object, st->md5_type);
 }
 
-
 /* Internal methods for a hash object */
 
 static void
 MD5_dealloc(PyObject *ptr)
 {
+ PyTypeObject *tp = Py_TYPE(ptr);
  PyObject_Del(ptr);
+ Py_DECREF(tp);
 }
 
 
@@ -342,16 +352,19 @@ MD5_dealloc(PyObject *ptr)
 /*[clinic input]
 MD5Type.copy
 
+ cls: defining_class
+
 Return a copy of the hash object.
 [clinic start generated code]*/
 
 static PyObject *
-MD5Type_copy_impl(MD5object *self)
-/*[clinic end generated code: output=596eb36852f02071 input=2c09e6d2493f3079]*/
+MD5Type_copy_impl(MD5object *self, PyTypeObject *cls)
+/*[clinic end generated code: output=bf055e08244bf5ee input=d89087dcfb2a8620]*/
 {
-MD5object *newobj;
+MD5State *st = PyType_GetModuleState(cls);
 
- if ((newobj = newMD5object())==NULL)
+ MD5object *newobj;
+ if ((newobj = newMD5object(st))==NULL)
  return NULL;
 
  newobj->hash_state = self->hash_state;
@@ -445,7 +458,6 @@ md5_get_digest_size(PyObject *self, void *closure)
  return PyLong_FromLong(MD5_DIGESTSIZE);
 }
 
-
 static PyGetSetDef MD5_getseters[] ={
 {"block_size",
  (getter)MD5_get_block_size, NULL,
@@ -462,40 +474,19 @@ static PyGetSetDef MD5_getseters[] ={
 {NULL} /* Sentinel */
 };
 
-static PyTypeObject MD5type ={
- PyVarObject_HEAD_INIT(NULL, 0)
- "_md5.md5", /*tp_name*/
- sizeof(MD5object), /*tp_basicsize*/
- 0, /*tp_itemsize*/
- /* methods */
- MD5_dealloc, /*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*/
- 0, /*tp_getattro*/
- 0, /*tp_setattro*/
- 0, /*tp_as_buffer*/
- Py_TPFLAGS_DEFAULT, /*tp_flags*/
- 0, /*tp_doc*/
- 0, /*tp_traverse*/
- 0, /*tp_clear*/
- 0, /*tp_richcompare*/
- 0, /*tp_weaklistoffset*/
- 0, /*tp_iter*/
- 0, /*tp_iternext*/
- MD5_methods, /* tp_methods */
- NULL, /* tp_members */
- MD5_getseters, /* tp_getset */
+static PyType_Slot md5_type_slots[] ={
+{Py_tp_dealloc, MD5_dealloc},
+{Py_tp_methods, MD5_methods},
+{Py_tp_getset, MD5_getseters},
+{0,0}
 };
 
+static PyType_Spec md5_type_spec ={
+ .name = "_md5.md5",
+ .basicsize = sizeof(MD5object),
+ .flags = Py_TPFLAGS_DEFAULT,
+ .slots = md5_type_slots
+};
 
 /* The single module-level function: new() */
 
@@ -519,7 +510,8 @@ _md5_md5_impl(PyObject *module, PyObject *string, int usedforsecurity)
  if (string)
  GET_BUFFER_VIEW_OR_ERROUT(string, &buf);
 
- if ((new = newMD5object()) == NULL){
+ MD5State *st = md5_get_state(module);
+ if ((new = newMD5object(st)) == NULL){
  if (string)
  PyBuffer_Release(&buf);
  return NULL;
@@ -549,37 +541,69 @@ static struct PyMethodDef MD5_functions[] ={
 {NULL, NULL} /* Sentinel */
 };
 
+static int
+_md5_traverse(PyObject *module, visitproc visit, void *arg)
+{
+ MD5State *state = md5_get_state(module);
+ Py_VISIT(state->md5_type);
+ return 0;
+}
+
+static int
+_md5_clear(PyObject *module)
+{
+ MD5State *state = md5_get_state(module);
+ Py_CLEAR(state->md5_type);
+ return 0;
+}
+
+static void
+_md5_free(void *module)
+{
+ _md5_clear((PyObject *)module);
+}
 
 /* Initialize this module. */
+static int
+md5_exec(PyObject *m)
+{
+ MD5State *st = md5_get_state(m);
+
+ st->md5_type = (PyTypeObject *)PyType_FromModuleAndSpec(
+ m, &md5_type_spec, NULL);
+
+ if (st->md5_type == NULL){
+ return -1;
+ }
+
+ Py_INCREF((PyObject *)st->md5_type);
+ if (PyModule_AddObject(m, "MD5Type", (PyObject *)st->md5_type) < 0){
+ Py_DECREF(st->md5_type);
+ return -1;
+ }
+
+ return 0;
+}
+
+static PyModuleDef_Slot _md5_slots[] ={
+{Py_mod_exec, md5_exec},
+{0, NULL}
+};
+
 
 static struct PyModuleDef _md5module ={
  PyModuleDef_HEAD_INIT,
- "_md5",
- NULL,
- -1,
- MD5_functions,
- NULL,
- NULL,
- NULL,
- NULL
+ .m_name = "_md5",
+ .m_size = sizeof(MD5State),
+ .m_methods = MD5_functions,
+ .m_slots = _md5_slots,
+ .m_traverse = _md5_traverse,
+ .m_clear = _md5_clear,
+ .m_free = _md5_free,
 };
 
 PyMODINIT_FUNC
 PyInit__md5(void)
 {
- PyObject *m;
-
- Py_SET_TYPE(&MD5type, &PyType_Type);
- if (PyType_Ready(&MD5type) < 0){
- return NULL;
- }
-
- m = PyModule_Create(&_md5module);
- if (m == NULL){
- return NULL;
- }
-
- Py_INCREF((PyObject *)&MD5type);
- PyModule_AddObject(m, "MD5Type", (PyObject *)&MD5type);
- return m;
+ return PyModuleDef_Init(&_md5module);
 }