networkd: add basic dbus API

Only the very basics, more to come.

For now:

$ busctl tree org.freedesktop.network1
└─/org/freedesktop/network1
  └─/org/freedesktop/network1/link
    ├─/org/freedesktop/network1/link/1
    ├─/org/freedesktop/network1/link/2
    ├─/org/freedesktop/network1/link/3
    ├─/org/freedesktop/network1/link/4
    ├─/org/freedesktop/network1/link/5
    ├─/org/freedesktop/network1/link/6
    ├─/org/freedesktop/network1/link/7
    ├─/org/freedesktop/network1/link/8
    └─/org/freedesktop/network1/link/9

$ busctl introspect org.freedesktop.network1 /org/freedesktop/network1
NAME                                TYPE      SIGNATURE RESULT/VALUE FLAGS
org.freedesktop.network1.Manager    interface -         -            -
.OperationalState                   property  s         "carrier" emits-change

$ busctl introspect org.freedesktop.network1 /org/freedesktop/network1/link/1
NAME                                TYPE      SIGNATURE RESULT/VALUE FLAGS
org.freedesktop.network1.Link       interface -         -            -
.AdministrativeState                property  s         "unmanaged" emits-change
.OperationalState                   property  s         "carrier" emits-change

1 files changed, 122 insertions, 0 deletions

diff --git a/src/network/networkd-link-bus.c b/src/network/networkd-link-bus.c
new file mode 100644
index 0000000000..645c47ae8c
--- /dev/null
+++ b/src/network/networkd-link-bus.c
@@ -0,0 +1,122 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2015 Tom Gundersen
+
+  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 "bus-util.h"
+#include "strv.h"
+
+#include "networkd.h"
+#include "networkd-link.h"
+
+static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_operational_state, link_operstate, LinkOperationalState);
+static BUS_DEFINE_PROPERTY_GET_ENUM(property_get_administrative_state, link_state, LinkState);
+
+const sd_bus_vtable link_vtable[] = {
+        SD_BUS_VTABLE_START(0),
+
+        SD_BUS_PROPERTY("OperationalState", "s", property_get_operational_state, offsetof(Link, operstate), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
+        SD_BUS_PROPERTY("AdministrativeState", "s", property_get_administrative_state, offsetof(Link, state), SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE),
+
+        SD_BUS_VTABLE_END
+};
+
+static char *link_bus_path(Link *link) {
+        char *p;
+
+        assert(link);
+        assert(link->ifindex > 0);
+
+        asprintf(&p, "/org/freedesktop/network1/link/%d", link->ifindex);
+
+        return p;
+}
+
+int link_node_enumerator(sd_bus *bus, const char *path, void *userdata, char ***nodes, sd_bus_error *error) {
+        _cleanup_strv_free_ char **l = NULL;
+        Manager *m = userdata;
+        Link *link;
+        Iterator i;
+        int r;
+
+        assert(bus);
+        assert(path);
+        assert(m);
+        assert(nodes);
+
+        HASHMAP_FOREACH(link, m->links, i) {
+                char *p;
+
+                p = link_bus_path(link);
+                if (!p)
+                        return -ENOMEM;
+
+                r = strv_consume(&l, p);
+                if (r < 0)
+                        return r;
+        }
+
+        *nodes = l;
+        l = NULL;
+
+        return 1;
+}
+
+int link_object_find(sd_bus *bus, const char *path, const char *interface, void *userdata, void **found, sd_bus_error *error) {
+        Manager *m = userdata;
+        Link *link;
+        int ifindex, r;
+
+        assert(bus);
+        assert(path);
+        assert(interface);
+        assert(m);
+        assert(found);
+
+        if (sscanf(path, "/org/freedesktop/network1/link/%d", &ifindex) != 1)
+                return 0;
+
+        r = link_get(m, ifindex, &link);
+        if (r < 0)
+                return 0;
+
+        *found = link;
+
+        return 1;
+}
+
+int link_send_changed(Link *link, const char *property, ...) {
+        _cleanup_free_ char *p = NULL;
+        char **l;
+
+        assert(link);
+        assert(link->manager);
+
+        l = strv_from_stdarg_alloca(property);
+
+        p = link_bus_path(link);
+        if (!p)
+                return -ENOMEM;
+
+        return sd_bus_emit_properties_changed_strv(
+                        link->manager->bus,
+                        p,
+                        "org.freedesktop.network1.Link",
+                        l);
+}