ubusd: add monitor support

[project/ubus.git] / ubusd_monitor.c

diff --git a/ubusd_monitor.c b/ubusd_monitor.c
new file mode 100644 (file)
index 0000000..82d0333
--- /dev/null
+++ b/ubusd_monitor.c
@@ -0,0 +1,110 @@
+/*
+ * Copyright (C) 2015 Felix Fietkau <nbd@openwrt.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1
+ * as published by the Free Software Foundation
+ *
+ * This program 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 General Public License for more details.
+ */
+
+#include "ubusd.h"
+
+static struct ubus_object *monitor_obj;
+static LIST_HEAD(monitors);
+
+struct ubus_monitor {
+       struct list_head list;
+       struct ubus_client *cl;
+       uint32_t seq;
+};
+
+static void
+ubusd_monitor_free(struct ubus_monitor *m)
+{
+       list_del(&m->list);
+       free(m);
+}
+
+static void
+ubusd_monitor_connect(struct ubus_client *cl, struct ubus_msg_buf *ub)
+{
+       struct ubus_monitor *m;
+
+       ubusd_monitor_disconnect(cl);
+
+       m = calloc(1, sizeof(*m));
+       m->cl = cl;
+       list_add(&m->list, &monitors);
+}
+
+void
+ubusd_monitor_disconnect(struct ubus_client *cl)
+{
+       struct ubus_monitor *m;
+
+       list_for_each_entry(m, &monitors, list) {
+               if (m->cl != cl)
+                       continue;
+
+               ubusd_monitor_free(m);
+               return;
+       }
+}
+
+void
+ubusd_monitor_message(struct ubus_client *cl, struct ubus_msg_buf *ub, bool send)
+{
+       static struct blob_buf mb;
+       struct ubus_monitor *m;
+
+       if (list_empty(&monitors))
+               return;
+
+       blob_buf_init(&mb, 0);
+       blob_put_int32(&mb, UBUS_MONITOR_CLIENT, cl->id.id);
+       blob_put_int32(&mb, UBUS_MONITOR_PEER, ub->hdr.peer);
+       blob_put_int32(&mb, UBUS_MONITOR_SEQ, ub->hdr.seq);
+       blob_put_int32(&mb, UBUS_MONITOR_TYPE, ub->hdr.type);
+       blob_put_int8(&mb, UBUS_MONITOR_SEND, send);
+       blob_put(&mb, UBUS_MONITOR_DATA, blob_data(ub->data), blob_len(ub->data));
+
+       list_for_each_entry(m, &monitors, list) {
+               ub = ubus_msg_new(mb.head, blob_raw_len(mb.head), true);
+               ub->hdr.type = UBUS_MSG_MONITOR;
+               ub->hdr.seq = ++m->seq;
+               ubus_msg_send(m->cl, ub, true);
+       }
+}
+
+static int
+ubusd_monitor_recv(struct ubus_client *cl, struct ubus_msg_buf *ub,
+                  const char *method, struct blob_attr *msg)
+{
+       /* Only root is allowed for now */
+       if (cl->uid != 0 || cl->gid != 0)
+               return UBUS_STATUS_PERMISSION_DENIED;
+
+       if (!strcmp(method, "add")) {
+               ubusd_monitor_connect(cl, ub);
+               return 0;
+       }
+
+       if (!strcmp(method, "remove")) {
+               ubusd_monitor_disconnect(cl);
+               return 0;
+       }
+
+       return UBUS_STATUS_METHOD_NOT_FOUND;
+}
+
+void
+ubusd_monitor_init(void)
+{
+       monitor_obj = ubusd_create_object_internal(NULL, UBUS_SYSTEM_OBJECT_MONITOR);
+       if (monitor_obj != NULL)
+               monitor_obj->recv_msg = ubusd_monitor_recv;
+}