ubus: add notification for subscribers present/gone

[project/ubus.git] / libubus.h

diff --git a/libubus.h b/libubus.h
index 55c59e4..19a4217 100644 (file)
--- a/libubus.h
+++ b/libubus.h
@@ -11,6 +11,9 @@
  * GNU General Public License for more details.
  */
 
+#ifndef __LIBUBUS_H
+#define __LIBUBUS_H
+
 #include <libubox/avl.h>
 #include <libubox/list.h>
 #include <libubox/blobmsg.h>
@@ -26,6 +29,7 @@ struct ubus_request;
 struct ubus_request_data;
 struct ubus_object_data;
 struct ubus_event_handler;
+struct ubus_subscriber;
 
 typedef void (*ubus_lookup_handler_t)(struct ubus_context *ctx,
                                      struct ubus_object_data *obj,
@@ -33,6 +37,9 @@ typedef void (*ubus_lookup_handler_t)(struct ubus_context *ctx,
 typedef int (*ubus_handler_t)(struct ubus_context *ctx, struct ubus_object *obj,
                              struct ubus_request_data *req,
                              const char *method, struct blob_attr *msg);
+typedef void (*ubus_state_handler_t)(struct ubus_context *ctx, struct ubus_object *obj);
+typedef void (*ubus_remove_handler_t)(struct ubus_context *ctx,
+                                     struct ubus_subscriber *obj, uint32_t id);
 typedef void (*ubus_event_handler_t)(struct ubus_context *ctx, struct ubus_event_handler *ev,
                                     const char *type, struct blob_attr *msg);
 typedef void (*ubus_data_handler_t)(struct ubus_request *req,
@@ -80,10 +87,20 @@ struct ubus_object {
        const char *path;
        struct ubus_object_type *type;
 
+       ubus_state_handler_t subscribe_cb;
+       bool has_subscribers;
+
        const struct ubus_method *methods;
        int n_methods;
 };
 
+struct ubus_subscriber {
+       struct ubus_object obj;
+
+       ubus_handler_t cb;
+       ubus_remove_handler_t remove_cb;
+};
+
 struct ubus_event_handler {
        struct ubus_object obj;
 
@@ -93,11 +110,13 @@ struct ubus_event_handler {
 struct ubus_context {
        struct list_head requests;
        struct avl_tree objects;
+       struct list_head pending;
 
        struct uloop_fd sock;
 
        uint32_t local_id;
        uint32_t request_seq;
+       int stack_depth;
 
        void (*connection_lost)(struct ubus_context *ctx);
 
@@ -118,6 +137,8 @@ struct ubus_request_data {
        uint32_t object;
        uint32_t peer;
        uint32_t seq;
+       bool deferred;
+       bool notify;
 };
 
 struct ubus_request {
@@ -142,13 +163,14 @@ struct ubus_request {
 
 
 struct ubus_context *ubus_connect(const char *path);
+int ubus_reconnect(struct ubus_context *ctx, const char *path);
 void ubus_free(struct ubus_context *ctx);
 
 const char *ubus_strerror(int error);
 
 static inline void ubus_add_uloop(struct ubus_context *ctx)
 {
-       uloop_fd_add(&ctx->sock, ULOOP_EDGE_TRIGGER | ULOOP_BLOCKING | ULOOP_READ);
+       uloop_fd_add(&ctx->sock, ULOOP_BLOCKING | ULOOP_READ);
 }
 
 /* call this for read events on ctx->sock.fd when not using uloop */
@@ -183,6 +205,11 @@ int ubus_add_object(struct ubus_context *ctx, struct ubus_object *obj);
 /* remove the object from the ubus connection */
 int ubus_remove_object(struct ubus_context *ctx, struct ubus_object *obj);
 
+/* add a subscriber notifications from another object */
+int ubus_register_subscriber(struct ubus_context *ctx, struct ubus_subscriber *obj);
+int ubus_subscribe(struct ubus_context *ctx, struct ubus_subscriber *obj, uint32_t id);
+int ubus_unsubscribe(struct ubus_context *ctx, struct ubus_subscriber *obj, uint32_t id);
+
 /* ----------- rpc ----------- */
 
 /* invoke a method on a specific object */
@@ -198,6 +225,17 @@ int ubus_invoke_async(struct ubus_context *ctx, uint32_t obj, const char *method
 int ubus_send_reply(struct ubus_context *ctx, struct ubus_request_data *req,
                    struct blob_attr *msg);
 
+static inline void ubus_defer_request(struct ubus_context *ctx,
+                                     struct ubus_request_data *req,
+                                     struct ubus_request_data *new_req)
+{
+    memcpy(new_req, req, sizeof(*req));
+    req->deferred = true;
+}
+
+void ubus_complete_deferred_request(struct ubus_context *ctx,
+                                   struct ubus_request_data *req, int ret);
+
 /* ----------- events ----------- */
 
 int ubus_send_event(struct ubus_context *ctx, const char *id,
@@ -212,3 +250,5 @@ static inline int ubus_unregister_event_handler(struct ubus_context *ctx,
 {
     return ubus_remove_object(ctx, &ev->obj);
 }
+
+#endif