Issue #11768: The signal handler of the signal module only calls
Py_AddPendingCall() for the first signal to fix a deadlock on reentrant or
parallel calls. PyErr_SetInterrupt() writes also into the wake up file.
diff --git a/Modules/signalmodule.c b/Modules/signalmodule.c
index 42d8dd8..1429770 100644
--- a/Modules/signalmodule.c
+++ b/Modules/signalmodule.c
@@ -164,6 +164,20 @@
}
static void
+trip_signal(int sig_num)
+{
+ Handlers[sig_num].tripped = 1;
+ if (is_tripped)
+ return;
+ /* Set is_tripped after setting .tripped, as it gets
+ cleared in PyErr_CheckSignals() before .tripped. */
+ is_tripped = 1;
+ Py_AddPendingCall(checksignals_witharg, NULL);
+ if (wakeup_fd != -1)
+ write(wakeup_fd, "\0", 1);
+}
+
+static void
signal_handler(int sig_num)
{
int save_errno = errno;
@@ -180,13 +194,7 @@
if (getpid() == main_pid)
#endif
{
- Handlers[sig_num].tripped = 1;
- /* Set is_tripped after setting .tripped, as it gets
- cleared in PyErr_CheckSignals() before .tripped. */
- is_tripped = 1;
- Py_AddPendingCall(checksignals_witharg, NULL);
- if (wakeup_fd != -1)
- write(wakeup_fd, "\0", 1);
+ trip_signal(sig_num);
}
#ifndef HAVE_SIGACTION
@@ -932,9 +940,7 @@
void
PyErr_SetInterrupt(void)
{
- is_tripped = 1;
- Handlers[SIGINT].tripped = 1;
- Py_AddPendingCall((int (*)(void *))PyErr_CheckSignals, NULL);
+ trip_signal(SIGINT);
}
void