bpo-43356: Allow passing a signal number to interrupt_main() (GH-24755)

Also introduce a new C API ``PyErr_SetInterruptEx(int signum)``.

1 files changed, 23 insertions, 7 deletions

diff --git a/Modules/_threadmodule.c b/Modules/_threadmodule.c
index f6217e6..0613dfd 100644
--- a/Modules/_threadmodule.c
+++ b/Modules/_threadmodule.c
@@ -9,6 +9,10 @@
 #include <stddef.h>               // offsetof()
 #include "structmember.h"         // PyMemberDef
 
+#ifdef HAVE_SIGNAL_H
+#  include <signal.h>             // SIGINT
+#endif
+
 // ThreadError is just an alias to PyExc_RuntimeError
 #define ThreadError PyExc_RuntimeError
 
@@ -1173,17 +1177,29 @@ This is synonymous to ``raise SystemExit''.  It will cause the current\n\
 thread to exit silently unless the exception is caught.");
 
 static PyObject *
-thread_PyThread_interrupt_main(PyObject * self, PyObject *Py_UNUSED(ignored))
+thread_PyThread_interrupt_main(PyObject *self, PyObject *args)
 {
-    PyErr_SetInterrupt();
+    int signum = SIGINT;
+    if (!PyArg_ParseTuple(args, "|i:signum", &signum)) {
+        return NULL;
+    }
+
+    if (PyErr_SetInterruptEx(signum)) {
+        PyErr_SetString(PyExc_ValueError, "signal number out of range");
+        return NULL;
+    }
     Py_RETURN_NONE;
 }
 
 PyDoc_STRVAR(interrupt_doc,
-"interrupt_main()\n\
+"interrupt_main(signum=signal.SIGINT, /)\n\
+\n\
+Simulate the arrival of the given signal in the main thread,\n\
+where the corresponding signal handler will be executed.\n\
+If *signum* is omitted, SIGINT is assumed.\n\
+A subthread can use this function to interrupt the main thread.\n\
 \n\
-Raise a KeyboardInterrupt in the main thread.\n\
-A subthread can use this function to interrupt the main thread."
+Note: the default signal hander for SIGINT raises ``KeyboardInterrupt``."
 );
 
 static lockobject *newlockobject(PyObject *module);
@@ -1527,8 +1543,8 @@ static PyMethodDef thread_methods[] = {
      METH_NOARGS, exit_doc},
     {"exit",                    thread_PyThread_exit_thread,
      METH_NOARGS, exit_doc},
-    {"interrupt_main",          thread_PyThread_interrupt_main,
-     METH_NOARGS, interrupt_doc},
+    {"interrupt_main",          (PyCFunction)thread_PyThread_interrupt_main,
+     METH_VARARGS, interrupt_doc},
     {"get_ident",               thread_get_ident,
      METH_NOARGS, get_ident_doc},
 #ifdef PY_HAVE_THREAD_NATIVE_ID