Restore original signal handlers in finished_callback

src/ansible_runner/interface.py

@@ -19,6 +19,7 @@
 #
 import os
 import json
+import signal
 import sys
 import threading
 import logging
@@ -89,11 +90,26 @@ def init_runner(**kwargs):
     status_callback_handler = kwargs.pop('status_handler', None)
     artifacts_handler = kwargs.pop('artifacts_handler', None)
     cancel_callback = kwargs.pop('cancel_callback', None)
+    finished_callback = kwargs.pop('finished_callback', None)
+
     if cancel_callback is None:
         # attempt to load signal handler.
         # will return None if we are not in the main thread
-        cancel_callback = signal_handler()
-    finished_callback = kwargs.pop('finished_callback', None)
+        cancel_callback, original_handlers = signal_handler()
+        if cancel_callback is not None:
+            # need to use finished_callback to restore signals
+            original_finished_callback = finished_callback
+
+            def restoring_finished_callback() -> None:
+                for signum, handler in original_handlers:
+                    if handler is None:
+                        # TODO this will silently fail to restore signal handlers set from outside Python
+                        continue
+                    signal.signal(signum, handler)
+                if original_finished_callback is not None:
+                    original_finished_callback()
+
+            finished_callback = restoring_finished_callback
 
     streamer = kwargs.pop('streamer', None)
     if streamer:

src/ansible_runner/utils/__init__.py

@@ -24,6 +24,7 @@
 from codecs import StreamReaderWriter
 from collections.abc import Callable, Iterable, MutableMapping
 from io import StringIO
+from types import FrameType
 from typing import Any, Iterator
 
 from ansible_runner.exceptions import ConfigurationError
@@ -503,7 +504,10 @@ def get_executable_path(name: str) -> str:
     return exec_path
 
 
-def signal_handler() -> Callable[[], bool] | None:
+_HANDLER = Callable[[int, FrameType | None], Any] | int | signal.Handlers | None
+
+
+def signal_handler() -> tuple[Callable[[], bool], list[tuple[signal.Signal, _HANDLER]]] | None:
     # Only the main thread is allowed to set a new signal handler
     # pylint: disable=W4902
     if threading.current_thread() is not threading.main_thread():
@@ -516,7 +520,11 @@ def _handler(number, frame):
         # pylint: disable=W0613
         signal_event.set()
 
+    original_handlers: list[tuple[signal.Signal, _HANDLER]] = []
+
+    original_handlers.append((signal.SIGTERM, signal.getsignal(signal.SIGTERM)))
     signal.signal(signal.SIGTERM, _handler)
+    original_handlers.append((signal.SIGINT, signal.getsignal(signal.SIGINT)))
     signal.signal(signal.SIGINT, _handler)
 
-    return signal_event.is_set
+    return signal_event.is_set, original_handlers

test/unit/utils/test_utils.py

@@ -289,7 +289,8 @@ def is_set(self):
     mocker.patch('ansible_runner.utils.threading.Event', MockEvent)
     mock_signal = mocker.patch('ansible_runner.utils.signal.signal')
 
-    assert signal_handler()() is False
+    callback, _ = signal_handler()
+    assert callback() is False
     assert mock_signal.call_args_list[0][0][0] == signal.SIGTERM
     assert mock_signal.call_args_list[1][0][0] == signal.SIGINT
 
@@ -300,7 +301,9 @@ def test_signal_handler_outside_main_thread(mocker):
     mocker.patch('ansible_runner.utils.threading.main_thread', return_value='thread0')
     mocker.patch('ansible_runner.utils.threading.current_thread', return_value='thread1')
 
-    assert signal_handler() is None
+    callback, original_handlers = signal_handler()
+    assert callback() is None
+    assert len(original_handlers) == 0
 
 
 def test_signal_handler_set(mocker):