nspawn: use Barrier API instead of eventfd-util

The Barrier-API simplifies cross-fork() synchronization a lot. Replace the
hard-coded eventfd-util implementation and drop it.

Compared to the old API, Barriers also handle exit() of the remote side as
abortion. This way, segfaults will not cause the parent to deadlock.

EINTR handling is currently ignored for any barrier-waits. This can easily
be added, but it isn't needed so far so I dropped it. EINTR handling in
general is ugly, anyway. You need to deal with pselect/ppoll/... variants
and make sure not to unblock signals at the wrong times. So genrally,
there's little use in adding it.

1 files changed, 0 insertions, 43 deletions

diff --git a/src/shared/eventfd-util.h b/src/shared/eventfd-util.h
deleted file mode 100644
index 0120f0409e..0000000000
--- a/src/shared/eventfd-util.h
+++ /dev/null
@@ -1,43 +0,0 @@
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
-#pragma once
-
-/***
-  This file is part of systemd.
-
-  Copyright 2014 Djalal Harouni
-
-  systemd is free software; you can redistribute it and/or modify it
-  under the terms of the GNU Lesser General Public License as published by
-  the Free Software Foundation; either version 2.1 of the License, or
-  (at your option) any later version.
-
-  systemd is distributed in the hope that it will be useful, but
-  WITHOUT ANY WARRANTY; without even the implied warranty of
-  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-  Lesser General Public License for more details.
-
-  You should have received a copy of the GNU Lesser General Public License
-  along with systemd; If not, see <http://www.gnu.org/licenses/>.
-***/
-
-#include <sys/types.h>
-#include <sys/eventfd.h>
-
-enum {
-        EVENTFD_INIT,
-        EVENTFD_START,
-        EVENTFD_PARENT_SUCCEEDED,
-        EVENTFD_PARENT_FAILED,
-        EVENTFD_CHILD_SUCCEEDED,
-        EVENTFD_CHILD_FAILED,
-};
-
-pid_t clone_with_eventfd(int flags, int eventfds[2]);
-
-int eventfd_send_state(int efd, eventfd_t s);
-int eventfd_recv_state(int efd, eventfd_t *e, eventfd_t s);
-
-int eventfd_recv_start(int efd);
-int eventfd_parent_succeeded(int efd);
-int eventfd_child_succeeded(int efd);