gh-108014: Add Py_IsFinalizing() function

Doc/c-api/init.rst

@@ -373,6 +373,14 @@
  :c:func:`Py_Initialize` is called again.
 
 
+.. c:function:: int Py_IsFinalizing()
+
+ Return non-zero if the Python interpreter is :term:`shutting down
+ <interpreter shutdown>`, return 0 otherwise.
+
+ .. versionadded:: 3.13
+
+
 .. c:function:: int Py_FinalizeEx()
 
  Undo all initializations made by :c:func:`Py_Initialize` and subsequent use of
@@ -852,7 +860,7 @@
  .. note::
  Calling this function from a thread when the runtime is finalizing
  will terminate the thread, even if the thread was not created by Python.
- You can use :c:func:`!_Py_IsFinalizing` or :func:`sys.is_finalizing` to
+ You can use :c:func:`Py_IsFinalizing` or :func:`sys.is_finalizing` to
  check if the interpreter is in process of being finalized before calling
  this function to avoid unwanted termination.
 
@@ -873,7 +881,7 @@
 The following functions use thread-local storage, and are not compatible
 with sub-interpreters:
 
 .. c:function:: PyGILState_STATE PyGILState_Ensure()
 
  Ensure that the current thread is ready to call the Python C API regardless
  of the current state of Python, or of the global interpreter lock. This may
@@ -898,11 +906,11 @@
  .. note::
  Calling this function from a thread when the runtime is finalizing
  will terminate the thread, even if the thread was not created by Python.
- You can use :c:func:`!_Py_IsFinalizing` or :func:`sys.is_finalizing` to
+ You can use :c:func:`Py_IsFinalizing` or :func:`sys.is_finalizing` to
  check if the interpreter is in process of being finalized before calling
  this function to avoid unwanted termination.
 
 .. c:function:: void PyGILState_Release(PyGILState_STATE)
 
  Release any resources previously acquired. After this call, Python's state will
  be the same as it was prior to the corresponding :c:func:`PyGILState_Ensure` call
@@ -1014,7 +1022,7 @@
  must be held.
 
  .. versionchanged:: 3.9
  This function now calls the :c:member:`PyThreadState.on_delete` callback.
  Previously, that happened in :c:func:`PyThreadState_Delete`.
 
 
@@ -1180,7 +1188,7 @@
  .. note::
  Calling this function from a thread when the runtime is finalizing
  will terminate the thread, even if the thread was not created by Python.
- You can use :c:func:`!_Py_IsFinalizing` or :func:`sys.is_finalizing` to
+ You can use :c:func:`Py_IsFinalizing` or :func:`sys.is_finalizing` to
  check if the interpreter is in process of being finalized before calling
  this function to avoid unwanted termination.
 
@@ -1639,7 +1647,7 @@
 
 .. c:var:: int PyTrace_LINE
 
  The value passed as the *what* parameter to a :c:type:`Py_tracefunc` function
  (but not a profiling function) when a line-number event is being reported.
  It may be disabled for a frame by setting :attr:`f_trace_lines` to *0* on that frame.
 
@@ -1670,7 +1678,7 @@
 
 .. c:var:: int PyTrace_OPCODE
 
  The value for the *what* parameter to :c:type:`Py_tracefunc` functions (but not
  profiling functions) when a new opcode is about to be executed. This event is
  not emitted by default: it must be explicitly requested by setting
  :attr:`f_trace_opcodes` to *1* on the frame.

Doc/whatsnew/3.13.rst

@@ -826,6 +826,10 @@ New Features
  not needed.
  (Contributed by Victor Stinner in :gh:`106004`.)
 
+* Add :c:func:`Py_IsFinalizing` function: check if the Python interpreter is
+ :term:`shutting down <interpreter shutdown>`.
+ (Contributed by Victor Stinner in :gh:`108014`.)
+
 Porting to Python 3.13
 ----------------------
 

Include/cpython/pylifecycle.h

@@ -81,3 +81,5 @@ PyAPI_FUNC(PyStatus) Py_NewInterpreterFromConfig(
 typedef void (*atexit_datacallbackfunc)(void *);
 PyAPI_FUNC(int) PyUnstable_AtExit(
  PyInterpreterState *, atexit_datacallbackfunc, void *);
+
+PyAPI_FUNC(int) Py_IsFinalizing(void);

Include/internal/pycore_pylifecycle.h

@@ -98,7 +98,6 @@ extern int _Py_FdIsInteractive(FILE *fp, PyObject *filename);
 extern const char* _Py_gitidentifier(void);
 extern const char* _Py_gitversion(void);
 
-extern int _Py_IsFinalizing(void);
 PyAPI_FUNC(int) _Py_IsInterpreterFinalizing(PyInterpreterState *interp);
 
 /* Random */

Misc/NEWS.d/next/C API/2023-08-16-17-16-19.gh-issue-108014.wXN3CF.rst

@@ -0,0 +1,2 @@
+Add :c:func:`Py_IsFinalizing` function: check if the Python interpreter is
+:term:`shutting down <interpreter shutdown>`. Patch by Victor Stinner.

Modules/_asynciomodule.c

@@ -529,7 +529,7 @@ future_init(FutureObj *fut, PyObject *loop)
  }
  if (is_true && !_Py_IsInterpreterFinalizing(_PyInterpreterState_GET())) {
  /* Only try to capture the traceback if the interpreter is not being
- finalized. The original motivation to add a `_Py_IsFinalizing()`
+ finalized. The original motivation to add a `Py_IsFinalizing()`
  call was to prevent SIGSEGV when a Future is created in a __del__
  method, which is called during the interpreter shutdown and the
  traceback module is already unloaded.

Python/pylifecycle.c

@@ -129,7 +129,7 @@ _PyRuntime_Finalize(void)
 }
 
 int
-_Py_IsFinalizing(void)
+Py_IsFinalizing(void)
 {
  return _PyRuntimeState_GetFinalizing(&_PyRuntime) != NULL;
 }

Python/sysmodule.c

@@ -2095,7 +2095,7 @@ static PyObject *
 sys_is_finalizing_impl(PyObject *module)
 /*[clinic end generated code: output=735b5ff7962ab281 input=f0df747a039948a5]*/
 {
- return PyBool_FromLong(_Py_IsFinalizing());
+ return PyBool_FromLong(Py_IsFinalizing());
 }
 
 #ifdef Py_STATS