bpo-39947: Add _PyThreadState_GetDict() function (GH-19160)

Author: vstinner

Include/cpython/pystate.h

@@ -149,6 +149,8 @@ PyAPI_FUNC(PyThreadState *) _PyThreadState_Prealloc(PyInterpreterState *);
  * if it is NULL. */
 PyAPI_FUNC(PyThreadState *) _PyThreadState_UncheckedGet(void);
 
+PyAPI_FUNC(PyObject *) _PyThreadState_GetDict(PyThreadState *tstate);
+
 /* PyGILState */
 
 /* Helper/diagnostic function - return 1 if the current thread

Modules/_asynciomodule.c

@@ -236,12 +236,13 @@ get_running_loop(PyObject **loop)
  rl = cached_running_holder; // borrowed
  }
  else {
- if (ts->dict == NULL) {
+ PyObject *ts_dict = _PyThreadState_GetDict(ts); // borrowed
+ if (ts_dict == NULL) {
  goto not_found;
  }
 
  rl = _PyDict_GetItemIdWithError(
- ts->dict, &PyId___asyncio_running_event_loop__); // borrowed
+ ts_dict, &PyId___asyncio_running_event_loop__); // borrowed
  if (rl == NULL) {
  if (PyErr_Occurred()) {
  goto error;

Python/pystate.c

@@ -4,9 +4,10 @@
 #include "Python.h"
 #include "pycore_ceval.h"
 #include "pycore_initconfig.h"
+#include "pycore_pyerrors.h"
+#include "pycore_pylifecycle.h"
 #include "pycore_pymem.h"
 #include "pycore_pystate.h"
-#include "pycore_pylifecycle.h"
 
 /* --------------------------------------------------------------------------
 CAUTION
@@ -979,20 +980,28 @@ PyThreadState_Swap(PyThreadState *newts)
  PyThreadState_GetDict() returns NULL, an exception has *not* been raised
  and the caller should assume no per-thread state is available. */
 
+PyObject *
+_PyThreadState_GetDict(PyThreadState *tstate)
+{
+ assert(tstate != NULL);
+ if (tstate->dict == NULL) {
+ tstate->dict = PyDict_New();
+ if (tstate->dict == NULL) {
+ _PyErr_Clear(tstate);
+ }
+ }
+ return tstate->dict;
+}
+
+
 PyObject *
 PyThreadState_GetDict(void)
 {
  PyThreadState *tstate = _PyThreadState_GET();
- if (tstate == NULL)
+ if (tstate == NULL) {
  return NULL;
-
- if (tstate->dict == NULL) {
- PyObject *d;
- tstate->dict = d = PyDict_New();
- if (d == NULL)
- PyErr_Clear();
  }
- return tstate->dict;
+ return _PyThreadState_GetDict(tstate);
 }