bpo-40077: Convert _queuemodule to use heap types

Misc/NEWS.d/next/Core and Builtins/2020-11-03-21-58-27.bpo-40077.a9qM1j.rst

@@ -0,0 +1 @@
+Convert :mod:`queue` to use heap types.

Modules/_queuemodule.c

@@ -1,16 +1,22 @@
 #include "Python.h"
+#include "structmember.h" // PyMemberDef
 #include <stddef.h> // offsetof()
 
-/*[clinic input]
-module _queue
-class _queue.SimpleQueue "simplequeueobject *" "&PySimpleQueueType"
-[clinic start generated code]*/
-/*[clinic end generated code: output=da39a3ee5e6b4b0d input=cf49af81bcbbbea6]*/
-
-static PyTypeObject PySimpleQueueType; /* forward decl */
-
-static PyObject *EmptyError;
+typedef struct{
+ PyTypeObject *SimpleQueueType;
+ PyObject *EmptyError;
+} simplequeue_state;
 
+static simplequeue_state *
+simplequeue_get_state(PyObject *module)
+{
+ simplequeue_state *state = PyModule_GetState(module);
+ assert(state);
+ return state;
+}
+static struct PyModuleDef queuemodule;
+#define simplequeue_get_state_by_type(tp) \
+ (simplequeue_get_state(_PyType_GetModuleByDef(type, &queuemodule)))
 
 typedef struct{
  PyObject_HEAD
@@ -21,10 +27,17 @@ typedef struct{
  PyObject *weakreflist;
 } simplequeueobject;
 
+/*[clinic input]
+module _queue
+class _queue.SimpleQueue "simplequeueobject *" "simplequeue_get_state_by_type(type)->SimpleQueueType"
+[clinic start generated code]*/
+/*[clinic end generated code: output=da39a3ee5e6b4b0d input=0a4023fe4d198c8d]*/
 
 static void
 simplequeue_dealloc(simplequeueobject *self)
 {
+ PyTypeObject *tp = Py_TYPE(self);
+
  PyObject_GC_UnTrack(self);
  if (self->lock != NULL){
  /* Unlock the lock so it's safe to free it */
@@ -36,6 +49,7 @@ simplequeue_dealloc(simplequeueobject *self)
  if (self->weakreflist != NULL)
  PyObject_ClearWeakRefs((PyObject *) self);
  Py_TYPE(self)->tp_free(self);
+ Py_DECREF(tp);
 }
 
 static int
@@ -155,6 +169,9 @@ simplequeue_pop_item(simplequeueobject *self)
 
 /*[clinic input]
 _queue.SimpleQueue.get
+
+ cls: defining_class
+ /
  block: bool = True
  timeout: object = None
 
@@ -171,9 +188,9 @@ in that case).
 [clinic start generated code]*/
 
 static PyObject *
-_queue_SimpleQueue_get_impl(simplequeueobject *self, int block,
- PyObject *timeout)
-/*[clinic end generated code: output=ec82a7157dcccd1a input=4bf691f9f01fa297]*/
+_queue_SimpleQueue_get_impl(simplequeueobject *self, PyTypeObject *cls,
+int block, PyObject *timeout)
+/*[clinic end generated code: output=1969aefa7db63666 input=5fc4d56b9a54757e]*/
 {
  _PyTime_t endtime = 0;
  _PyTime_t timeout_val;
@@ -225,8 +242,10 @@ _queue_SimpleQueue_get_impl(simplequeueobject *self, int block,
  return NULL;
  }
  if (r == PY_LOCK_FAILURE){
+ PyObject *module = PyType_GetModule(cls);
+ simplequeue_state *state = simplequeue_get_state(module);
  /* Timed out */
- PyErr_SetNone(EmptyError);
+ PyErr_SetNone(state->EmptyError);
  return NULL;
  }
  self->locked = 1;
@@ -251,17 +270,21 @@ _queue_SimpleQueue_get_impl(simplequeueobject *self, int block,
 /*[clinic input]
 _queue.SimpleQueue.get_nowait
 
+ cls: defining_class
+ /
+
 Remove and return an item from the queue without blocking.
 
 Only get an item if one is immediately available. Otherwise
 raise the Empty exception.
 [clinic start generated code]*/
 
 static PyObject *
-_queue_SimpleQueue_get_nowait_impl(simplequeueobject *self)
-/*[clinic end generated code: output=a89731a75dbe4937 input=6fe5102db540a1b9]*/
+_queue_SimpleQueue_get_nowait_impl(simplequeueobject *self,
+ PyTypeObject *cls)
+/*[clinic end generated code: output=620c58e2750f8b8a input=842f732bf04216d3]*/
 {
- return _queue_SimpleQueue_get_impl(self, 0, Py_None);
+ return _queue_SimpleQueue_get_impl(self, cls, 0, Py_None);
 }
 
 /*[clinic input]
@@ -290,6 +313,29 @@ _queue_SimpleQueue_qsize_impl(simplequeueobject *self)
  return PyList_GET_SIZE(self->lst) - self->lst_pos;
 }
 
+static int
+queue_traverse(PyObject *m, visitproc visit, void *arg)
+{
+ simplequeue_state *state = simplequeue_get_state(m);
+ Py_VISIT(state->SimpleQueueType);
+ Py_VISIT(state->EmptyError);
+ return 0;
+}
+
+static int
+queue_clear(PyObject *m)
+{
+ simplequeue_state *state = simplequeue_get_state(m);
+ Py_CLEAR(state->SimpleQueueType);
+ Py_CLEAR(state->EmptyError);
+ return 0;
+}
+
+static void
+queue_free(void *m)
+{
+ queue_clear((PyObject *)m);
+}
 
 #include "clinic/_queuemodule.c.h"
 
@@ -306,48 +352,26 @@ static PyMethodDef simplequeue_methods[] ={
 {NULL, NULL} /* sentinel */
 };
 
+static struct PyMemberDef simplequeue_members[] ={
+{"__weaklistoffset__", T_PYSSIZET, offsetof(simplequeueobject, weakreflist), READONLY},
+{NULL},
+};
+
+static PyType_Slot simplequeue_slots[] ={
+{Py_tp_dealloc, simplequeue_dealloc},
+{Py_tp_doc, (void *)simplequeue_new__doc__},
+{Py_tp_traverse, simplequeue_traverse},
+{Py_tp_members, simplequeue_members},
+{Py_tp_methods, simplequeue_methods},
+{Py_tp_new, simplequeue_new},
+{0, NULL},
+};
 
-static PyTypeObject PySimpleQueueType ={
- PyVarObject_HEAD_INIT(NULL, 0)
- "_queue.SimpleQueue", /*tp_name*/
- sizeof(simplequeueobject), /*tp_basicsize*/
- 0, /*tp_itemsize*/
- /* methods */
- (destructor)simplequeue_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 | Py_TPFLAGS_BASETYPE
- | Py_TPFLAGS_HAVE_GC, /* tp_flags */
- simplequeue_new__doc__, /*tp_doc*/
- (traverseproc)simplequeue_traverse, /*tp_traverse*/
- 0, /*tp_clear*/
- 0, /*tp_richcompare*/
- offsetof(simplequeueobject, weakreflist), /*tp_weaklistoffset*/
- 0, /*tp_iter*/
- 0, /*tp_iternext*/
- simplequeue_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 */
- simplequeue_new /* tp_new */
+static PyType_Spec simplequeue_spec ={
+ .name = "_queue.SimpleQueue",
+ .basicsize = sizeof(simplequeueobject),
+ .flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE | Py_TPFLAGS_HAVE_GC,
+ .slots = simplequeue_slots,
 };
 
 
@@ -358,42 +382,54 @@ PyDoc_STRVAR(queue_module_doc,
 This module is an implementation detail, please do not use it directly.");
 
 static struct PyModuleDef queuemodule ={
- PyModuleDef_HEAD_INIT,
- "_queue",
- queue_module_doc,
- -1,
- NULL,
- NULL,
- NULL,
- NULL,
- NULL
+ .m_base = PyModuleDef_HEAD_INIT,
+ .m_name = "_queue",
+ .m_doc = queue_module_doc,
+ .m_size = sizeof(simplequeue_state),
+ .m_traverse = queue_traverse,
+ .m_clear = queue_clear,
+ .m_free = queue_free,
 };
 
 
 PyMODINIT_FUNC
 PyInit__queue(void)
 {
  PyObject *m;
+ simplequeue_state *state;
 
  /* Create the module */
  m = PyModule_Create(&queuemodule);
  if (m == NULL)
  return NULL;
 
- EmptyError = PyErr_NewExceptionWithDoc(
+ state = simplequeue_get_state(m);
+ state->EmptyError = PyErr_NewExceptionWithDoc(
  "_queue.Empty",
  "Exception raised by Queue.get(block=0)/get_nowait().",
  NULL, NULL);
- if (EmptyError == NULL)
-return NULL;
+ if (state->EmptyError == NULL)
+goto error;
 
- Py_INCREF(EmptyError);
- if (PyModule_AddObject(m, "Empty", EmptyError) < 0)
- return NULL;
+ Py_INCREF(state->EmptyError);
+ if (PyModule_AddObject(m, "Empty", state->EmptyError) < 0){
+ Py_DECREF(state->EmptyError);
+ goto error;
+ }
 
- if (PyModule_AddType(m, &PySimpleQueueType) < 0){
- return NULL;
+ state->SimpleQueueType = (PyTypeObject *)PyType_FromModuleAndSpec(m,
+ &simplequeue_spec,
+ NULL);
+ if (state->SimpleQueueType == NULL){
+ goto error;
+ }
+ if (PyModule_AddType(m, state->SimpleQueueType) < 0){
+ goto error;
  }
 
  return m;
+
+error:
+ Py_DECREF(m);
+ return NULL;
 }