Merge ~kissiel/checkbox-ng:fix-non-killable-process-nests into checkbox-ng:master

[Maciej Kisielewski]

This patch helps with interrupting runaway processes (groups of processes, to be precise).

For processes that had a structure like this:

foo | bar | baz

In case where foo command failed, if the operator hit ctrl+c the signal went to already non existent pid1, while pipes were still open to the whole chain.

This patch makes checkbox close the pipes when kill command is issued. It also changes the method of killing to the new one, which is more reliable when running root jobs.

Tested by running multiple weird jobs, including the nefarious `more file |cat`. With and without `user: root`.

[Sylvain Pineau (sylvain-pineau)]

+1

review: Approve

diff --git a/plainbox/impl/execution.py b/plainbox/impl/execution.py
index 01e783f..db4d73e 100644
--- a/plainbox/impl/execution.py
+++ b/plainbox/impl/execution.py
@@ -216,6 +216,7 @@ class UnifiedRunner(IJobRunner):
                             time.sleep(0.1)
                 except BrokenPipeError:
                     pass
+                os.close(in_w)
             forwarder_thread = threading.Thread(
                 target=stdin_forwarder, args=(stdin,))
             forwarder_thread.start()
@@ -241,8 +242,9 @@ class UnifiedRunner(IJobRunner):
                         proc.wait()
                         break
                     except KeyboardInterrupt:
-                        # On interrupt send a signal to the process
-                        extcmd_popen._on_keyboard_interrupt(proc)
+                        is_alive = False
+                        import signal
+                        self.send_signal(signal.SIGKILL, target_user)
                         # And send a notification about this
                         extcmd_popen._delegate.on_interrupt()
             finally: