From a69f062cbd4041229f8d29ef9647bf783df414c1 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Fri, 14 Dec 2012 13:00:49 +0100 Subject: [PATCH] ubus: add notification for subscribers present/gone Signed-off-by: Felix Fietkau --- examples/client.c | 9 ++++++++- libubus-internal.h | 1 + libubus-sub.c | 18 ++++++++++++++++++ libubus.c | 4 ++++ libubus.h | 5 +++++ ubusd_obj.c | 9 +++++++++ ubusd_obj.h | 1 + ubusd_proto.c | 14 ++++++++++++++ ubusmsg.h | 9 +++++++++ 9 files changed, 69 insertions(+), 1 deletion(-) diff --git a/examples/client.c b/examples/client.c index 315a8e3..418fb15 100644 --- a/examples/client.c +++ b/examples/client.c @@ -18,7 +18,14 @@ static struct ubus_context *ctx; static struct blob_buf b; -static struct ubus_object test_client_object = {}; +static void test_client_subscribe_cb(struct ubus_context *ctx, struct ubus_object *obj) +{ + fprintf(stderr, "Subscribers active: %d\n", obj->has_subscribers); +} + +static struct ubus_object test_client_object = { + .subscribe_cb = test_client_subscribe_cb, +}; static void client_main(void) { diff --git a/libubus-internal.h b/libubus-internal.h index f3e2a73..072bf8e 100644 --- a/libubus-internal.h +++ b/libubus-internal.h @@ -27,5 +27,6 @@ void ubus_process_invoke(struct ubus_context *ctx, struct ubus_msghdr *hdr); int __hidden ubus_start_request(struct ubus_context *ctx, struct ubus_request *req, struct blob_attr *msg, int cmd, uint32_t peer); void ubus_process_unsubscribe(struct ubus_context *ctx, struct ubus_msghdr *hdr); +void ubus_process_notify(struct ubus_context *ctx, struct ubus_msghdr *hdr); #endif diff --git a/libubus-sub.c b/libubus-sub.c index 2bfb483..87c8128 100644 --- a/libubus-sub.c +++ b/libubus-sub.c @@ -91,4 +91,22 @@ void __hidden ubus_process_unsubscribe(struct ubus_context *ctx, struct ubus_msg s->remove_cb(ctx, s, blob_get_u32(attrbuf[UBUS_ATTR_TARGET])); } +void __hidden ubus_process_notify(struct ubus_context *ctx, struct ubus_msghdr *hdr) +{ + struct blob_attr **attrbuf; + struct ubus_object *obj; + uint32_t objid; + + attrbuf = ubus_parse_msg(hdr->data); + if (!attrbuf[UBUS_ATTR_OBJID] || !attrbuf[UBUS_ATTR_ACTIVE]) + return; + objid = blob_get_u32(attrbuf[UBUS_ATTR_OBJID]); + obj = avl_find_element(&ctx->objects, &objid, obj, avl); + if (!obj) + return; + + obj->has_subscribers = blob_get_u8(attrbuf[UBUS_ATTR_ACTIVE]); + if (obj->subscribe_cb) + obj->subscribe_cb(ctx, obj); +} diff --git a/libubus.c b/libubus.c index 03899d6..dffbfeb 100644 --- a/libubus.c +++ b/libubus.c @@ -232,6 +232,10 @@ void __hidden ubus_process_msg(struct ubus_context *ctx, struct ubus_msghdr *hdr case UBUS_MSG_UNSUBSCRIBE: ubus_process_unsubscribe(ctx, hdr); break; + + case UBUS_MSG_NOTIFY: + ubus_process_notify(ctx, hdr); + break; } } diff --git a/libubus.h b/libubus.h index 17c4952..19a4217 100644 --- a/libubus.h +++ b/libubus.h @@ -37,6 +37,7 @@ 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, @@ -86,6 +87,9 @@ 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; }; @@ -134,6 +138,7 @@ struct ubus_request_data { uint32_t peer; uint32_t seq; bool deferred; + bool notify; }; struct ubus_request { diff --git a/ubusd_obj.c b/ubusd_obj.c index 8b1b18f..69ca8b8 100644 --- a/ubusd_obj.c +++ b/ubusd_obj.c @@ -167,6 +167,7 @@ free: void ubus_subscribe(struct ubus_object *obj, struct ubus_object *target, const char *method) { struct ubus_subscription *s; + bool first = list_empty(&target->subscribers); s = calloc(1, sizeof(*s) + strlen(method) + 1); if (!s) @@ -177,13 +178,21 @@ void ubus_subscribe(struct ubus_object *obj, struct ubus_object *target, const c list_add(&s->list, &target->subscribers); list_add(&s->target_list, &obj->target_list); strcpy(s->method, method); + + if (first) + ubus_notify_subscription(target); } void ubus_unsubscribe(struct ubus_subscription *s) { + struct ubus_object *obj = s->target; + list_del(&s->list); list_del(&s->target_list); free(s); + + if (list_empty(&obj->subscribers)) + ubus_notify_subscription(obj); } void ubusd_free_object(struct ubus_object *obj) diff --git a/ubusd_obj.h b/ubusd_obj.h index 5a82e8d..8e80078 100644 --- a/ubusd_obj.h +++ b/ubusd_obj.h @@ -79,5 +79,6 @@ static inline struct ubus_object *ubusd_find_object(uint32_t objid) void ubus_subscribe(struct ubus_object *obj, struct ubus_object *target, const char *method); void ubus_unsubscribe(struct ubus_subscription *s); void ubus_notify_unsubscribe(struct ubus_subscription *s); +void ubus_notify_subscription(struct ubus_object *obj); #endif diff --git a/ubusd_proto.c b/ubusd_proto.c index 59920ed..283cb77 100644 --- a/ubusd_proto.c +++ b/ubusd_proto.c @@ -416,6 +416,20 @@ void ubusd_proto_free_client(struct ubus_client *cl) ubus_free_id(&clients, &cl->id); } +void ubus_notify_subscription(struct ubus_object *obj) +{ + bool active = !list_empty(&obj->subscribers); + struct ubus_msg_buf *ub; + + blob_buf_init(&b, 0); + blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id.id); + blob_put_int8(&b, UBUS_ATTR_ACTIVE, active); + + ub = ubus_msg_from_blob(false); + ubus_msg_init(ub, UBUS_MSG_NOTIFY, ++obj->invoke_seq, 0); + ubus_msg_send(obj->client, ub, true); +} + void ubus_notify_unsubscribe(struct ubus_subscription *s) { struct ubus_msg_buf *ub; diff --git a/ubusmsg.h b/ubusmsg.h index 833d7bf..fc4eedd 100644 --- a/ubusmsg.h +++ b/ubusmsg.h @@ -62,6 +62,13 @@ enum ubus_msg_type { UBUS_MSG_SUBSCRIBE, UBUS_MSG_UNSUBSCRIBE, + /* + * send a notification to all subscribers of an object. + * when sent from the server, it indicates a subscription + * status change + */ + UBUS_MSG_NOTIFY, + /* must be last */ __UBUS_MSG_LAST, }; @@ -81,6 +88,8 @@ enum ubus_msg_attr { UBUS_ATTR_DATA, UBUS_ATTR_TARGET, + UBUS_ATTR_ACTIVE, + /* must be last */ UBUS_ATTR_MAX, }; -- 2.11.0