networkd: add networkd-wait-online

This is mostly a proof of concept to try sd-network, so we don't
hook it up with a .service file quite yet. We probably want it to
be more clever about deciding when we are 'online'.

The binary  will wait for at least one network managed by networkd,
and until all networks managed by networkd are configured.

Makefile.am

@@ -4047,6 +4047,16 @@ nodist_systemunit_DATA += \
 GENERAL_ALIASES += \
 	$(systemunitdir)/systemd-networkd.service $(pkgsysconfdir)/system/multi-user.target.wants/systemd-networkd.service
 
+rootlibexec_PROGRAMS += \
+	systemd-networkd-wait-online
+
+systemd_networkd_wait_online_SOURCES = \
+	src/network/networkd-wait-online.c
+
+systemd_networkd_wait_online_LDADD = \
+	libsystemd-internal.la \
+	libsystemd-network.la
+
 test_network_SOURCES = \
 	src/network/test-network.c
 

src/network/networkd-wait-online.c

@@ -0,0 +1,142 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2013 Tom Gundersen <teg@jklm.no>
+
+  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 "sd-event.h"
+#include "sd-daemon.h"
+#include "sd-network.h"
+
+#include "util.h"
+
+static bool all_configured(void) {
+        _cleanup_free_ unsigned *indices = NULL;
+        bool one_ready = false;
+        int r, n, i;
+
+        n = sd_network_get_ifindices(&indices);
+        if (n <= 0)
+                return false;
+
+        for (i = 0; i < n; i++) {
+                _cleanup_free_ char *state = NULL;
+
+                r = sd_network_get_link_state(indices[i], &state);
+                if (r < 0)
+                        return false;
+
+                if (streq(state, "configured"))
+                        one_ready = true;
+
+                if (!streq(state, "configured") && !streq(state, "unmanaged"))
+                        return false;
+        }
+
+        if (one_ready)
+                return true;
+
+        return false;
+}
+
+static int event_handler(sd_event_source *s, int fd, uint32_t revents,
+                         void *userdata) {
+        sd_event *event = userdata;
+
+        assert(event);
+
+        if (all_configured())
+                sd_event_exit(event, 0);
+
+        return 1;
+}
+
+int main(int argc, char *argv[]) {
+        sd_event *event;
+        sd_event_source *event_source;
+        sd_network_monitor *monitor;
+        int r, fd, events;
+
+        log_set_target(LOG_TARGET_AUTO);
+        log_parse_environment();
+        log_open();
+
+        umask(0022);
+
+        if (argc != 1) {
+                log_error("This program takes no arguments.");
+                r = -EINVAL;
+                goto out;
+        }
+
+        r = sd_network_monitor_new(NULL, &monitor);
+        if (r < 0) {
+                log_error("Could not create monitor: %s", strerror(-r));
+                goto out;
+        }
+
+        r = sd_event_new(&event);
+        if (r < 0) {
+                log_error("Could not create event: %s", strerror(-r));
+                goto out;
+        }
+
+        fd = sd_network_monitor_get_fd(monitor);
+        if (fd < 0) {
+                log_error("Could not get monitor fd: %s", strerror(-r));
+                goto out;
+        }
+
+        events = sd_network_monitor_get_events(monitor);
+        if (events < 0) {
+                log_error("Could not get monitor events: %s", strerror(-r));
+                goto out;
+        }
+
+        r = sd_event_add_io(event, &event_source, fd, events, &event_handler,
+                            event);
+        if (r < 0) {
+                log_error("Could not add io event source: %s", strerror(-r));
+                goto out;
+        }
+
+        if (all_configured()) {
+                r = 0;
+                goto out;
+        }
+
+        sd_notify(false,
+                  "READY=1\n"
+                  "STATUS=Waiting for network connecitons...");
+
+        r = sd_event_loop(event);
+        if (r < 0) {
+                log_error("Event loop failed: %s", strerror(-r));
+                goto out;
+        }
+
+out:
+        sd_notify(false,
+                  "STATUS=All interfaces configured...");
+
+        sd_event_source_unref(event_source);
+        sd_event_unref(event);
+        sd_network_monitor_unref(monitor);
+
+        return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
+}