tree-wide: drop 'This file is part of systemd' blurb

[elogind.git] / src / cgroups-agent / cgroups-agent.c

diff --git a/src/cgroups-agent/cgroups-agent.c b/src/cgroups-agent/cgroups-agent.c
index f0371f23ee144953b44e347ab327b2fbf9709f56..b98c0432cd96aa7c00c79aa10cd71434ce64c138 100644 (file)
--- a/src/cgroups-agent/cgroups-agent.c
+++ b/src/cgroups-agent/cgroups-agent.c
@@ -1,34 +1,28 @@
-/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
-
+/* SPDX-License-Identifier: LGPL-2.1+ */
 /***
-  This file is part of systemd.
-
   Copyright 2010 Lennart Poettering
-
-  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 <stdlib.h>
+#include <sys/socket.h>
 
-#include "sd-bus.h"
-#include "bus-util.h"
-#include "musl_missing.h"
+#include "fd-util.h"
 #include "log.h"
+#include "socket-util.h"
+
+/// Additional includes needed by elogind
+#include "musl_missing.h"
 
 int main(int argc, char *argv[]) {
-        _cleanup_bus_flush_close_unref_ sd_bus *bus = NULL;
-        int r;
+
+        static const union sockaddr_union sa = {
+                .un.sun_family = AF_UNIX,
+                .un.sun_path = "/run/systemd/cgroups-agent",
+        };
+
+        _cleanup_close_ int fd = -1;
+        ssize_t n;
+        size_t l;
 
         if (argc != 2) {
                 log_error("Incorrect number of arguments.");
@@ -40,46 +34,22 @@ int main(int argc, char *argv[]) {
         log_parse_environment();
         log_open();
 
-#if 0
-        /* We send this event to the private D-Bus socket and then the
-         * system instance will forward this to the system bus. We do
-         * this to avoid an activation loop when we start dbus when we
-         * are called when the dbus service is shut down. */
+        fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0);
+        if (fd < 0) {
+                log_debug_errno(errno, "Failed to allocate socket: %m");
+                return EXIT_FAILURE;
+        }
 
-        r = bus_connect_system_systemd(&bus);
-#else
-        /* Unlike in systemd where this has to use a private socket,
-           since elogind doesn't associate control groups with services
-           and doesn't manage the dbus service, we can just use the
-           system bus.  */
-        r = sd_bus_open_system(&bus);
-#endif // 0
+        l = strlen(argv[1]);
 
-        if (r < 0) {
-#if 0
-                /* If we couldn't connect we assume this was triggered
-                 * while systemd got restarted/transitioned from
-                 * initrd to the system, so let's ignore this */
-                log_debug_errno(r, "Failed to get D-Bus connection: %m");
-#else
-                /* If dbus isn't running or responding, there is nothing
-                 * we can do about it. */
-                log_debug_errno(r, "Failed to open system bus: %m");
-#endif // 0
+        n = sendto(fd, argv[1], l, 0, &sa.sa, SOCKADDR_UN_LEN(sa.un));
+        if (n < 0) {
+                log_debug_errno(errno, "Failed to send cgroups agent message: %m");
                 return EXIT_FAILURE;
         }
 
-        r = sd_bus_emit_signal(bus,
-                               "/org/freedesktop/elogind/agent",
-                               "org.freedesktop.elogind.Agent",
-                               "Released",
-                               "s", argv[1]);
-        if (r < 0) {
-#if 0
-                log_debug_errno(r, "Failed to send signal message on private connection: %m");
-#else
-                log_debug_errno(r, "Failed to send signal message: %m");
-#endif // 0
+        if ((size_t) n != l) {
+                log_debug("Datagram size mismatch");
                 return EXIT_FAILURE;
         }