bpo-41686: Always create the SIGINT event on Windows (GH-23344) (GH-23347)
bpo-41686, bpo-41713: On Windows, the SIGINT event,
_PyOS_SigintEvent(), is now created even if Python is configured to
not install signal handlers (PyConfig.install_signal_handlers=0 or
Py_InitializeEx(0)).
diff --git a/Include/internal/pycore_pylifecycle.h b/Include/internal/pycore_pylifecycle.h
index b76bb2c..50ab645 100644
--- a/Include/internal/pycore_pylifecycle.h
+++ b/Include/internal/pycore_pylifecycle.h
@@ -68,6 +68,7 @@
extern void _PySlice_Fini(void);
extern void _PyAsyncGen_Fini(void);
+extern int _PySignal_Init(int install_signal_handlers);
extern void PyOS_FiniInterrupts(void);
extern void _PyExc_Fini(void);
diff --git a/Misc/NEWS.d/next/Core and Builtins/2020-11-17-16-25-50.bpo-41686.hX77kL.rst b/Misc/NEWS.d/next/Core and Builtins/2020-11-17-16-25-50.bpo-41686.hX77kL.rst
new file mode 100644
index 0000000..0265d48
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2020-11-17-16-25-50.bpo-41686.hX77kL.rst
@@ -0,0 +1,4 @@
+On Windows, the ``SIGINT`` event, ``_PyOS_SigintEvent()``, is now created
+even if Python is configured to not install signal handlers (if
+:c:member:`PyConfig.install_signal_handlers` equals to 0, or
+``Py_InitializeEx(0)``).
diff --git a/Modules/signalmodule.c b/Modules/signalmodule.c
index 9041848..540e2d9 100644
--- a/Modules/signalmodule.c
+++ b/Modules/signalmodule.c
@@ -1632,11 +1632,6 @@
goto finally;
#endif
-#ifdef MS_WINDOWS
- /* Create manual-reset event, initially unset */
- sigint_event = CreateEvent(NULL, TRUE, FALSE, FALSE);
-#endif
-
if (PyErr_Occurred()) {
Py_DECREF(m);
m = NULL;
@@ -1773,6 +1768,53 @@
}
}
+
+static int
+signal_install_handlers(void)
+{
+#ifdef SIGPIPE
+ PyOS_setsig(SIGPIPE, SIG_IGN);
+#endif
+#ifdef SIGXFZ
+ PyOS_setsig(SIGXFZ, SIG_IGN);
+#endif
+#ifdef SIGXFSZ
+ PyOS_setsig(SIGXFSZ, SIG_IGN);
+#endif
+
+ // Import _signal to install the Python SIGINT handler
+ PyObject *module = PyImport_ImportModule("_signal");
+ if (!module) {
+ return -1;
+ }
+ Py_DECREF(module);
+
+ return 0;
+}
+
+
+int
+_PySignal_Init(int install_signal_handlers)
+{
+#ifdef MS_WINDOWS
+ /* Create manual-reset event, initially unset */
+ sigint_event = CreateEvent(NULL, TRUE, FALSE, FALSE);
+ if (sigint_event == NULL) {
+ PyErr_SetFromWindowsErr(0);
+ return -1;
+ }
+#endif
+
+ if (install_signal_handlers) {
+ if (signal_install_handlers() < 0) {
+ return -1;
+ }
+ }
+
+ return 0;
+}
+
+
void
PyOS_FiniInterrupts(void)
{
diff --git a/Python/pylifecycle.c b/Python/pylifecycle.c
index cfb3a7d..5c50d4d 100644
--- a/Python/pylifecycle.c
+++ b/Python/pylifecycle.c
@@ -57,7 +57,6 @@
static PyStatus init_import_site(void);
static PyStatus init_set_builtins_open(void);
static PyStatus init_sys_streams(PyThreadState *tstate);
-static PyStatus init_signals(PyThreadState *tstate);
static void call_py_exitfuncs(PyThreadState *tstate);
static void wait_for_thread_shutdown(PyThreadState *tstate);
static void call_ll_exitfuncs(_PyRuntimeState *runtime);
@@ -1013,11 +1012,8 @@
}
if (is_main_interp) {
- if (config->install_signal_handlers) {
- status = init_signals(tstate);
- if (_PyStatus_EXCEPTION(status)) {
- return status;
- }
+ if (_PySignal_Init(config->install_signal_handlers) < 0) {
+ return _PyStatus_ERR("can't initialize signals");
}
if (_PyTraceMalloc_Init(config->tracemalloc) < 0) {
@@ -2442,25 +2438,6 @@
exit(sts);
}
-static PyStatus
-init_signals(PyThreadState *tstate)
-{
-#ifdef SIGPIPE
- PyOS_setsig(SIGPIPE, SIG_IGN);
-#endif
-#ifdef SIGXFZ
- PyOS_setsig(SIGXFZ, SIG_IGN);
-#endif
-#ifdef SIGXFSZ
- PyOS_setsig(SIGXFSZ, SIG_IGN);
-#endif
- PyOS_InitInterrupts(); /* May imply init_signals() */
- if (_PyErr_Occurred(tstate)) {
- return _PyStatus_ERR("can't import signal");
- }
- return _PyStatus_OK();
-}
-
/* Restore signals that the interpreter has called SIG_IGN on to SIG_DFL.
*