libubus-sub.c

   1 /*
   2  * Copyright (C) 2011-2012 Felix Fietkau <nbd@openwrt.org>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU Lesser General Public License version 2.1
   6  * as published by the Free Software Foundation
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include "libubus.h"
  15 #include "libubus-internal.h"
  16
  17 static int ubus_subscriber_cb(struct ubus_context *ctx, struct ubus_object *obj,
  18                          struct ubus_request_data *req,
  19                          const char *method, struct blob_attr *msg)
  20 {
  21         struct ubus_subscriber *s;
  22
  23         s = container_of(obj, struct ubus_subscriber, obj);
  24         s->cb(ctx, obj, req, method, msg);
  25         return 0;
  26 }
  27
  28 static const struct ubus_method watch_method = {
  29         .name = NULL,
  30         .handler = ubus_subscriber_cb,
  31 };
  32
  33 int ubus_register_subscriber(struct ubus_context *ctx, struct ubus_subscriber *s)
  34 {
  35         struct ubus_object *obj = &s->obj;
  36
  37         obj->methods = &watch_method;
  38         obj->n_methods = 1;
  39
  40         return ubus_add_object(ctx, obj);
  41 }
  42
  43 static int
  44 __ubus_subscribe_request(struct ubus_context *ctx, struct ubus_object *obj, uint32_t id, int type)
  45 {
  46         struct ubus_request req;
  47
  48         blob_buf_init(&b, 0);
  49         blob_put_int32(&b, UBUS_ATTR_OBJID, obj->id);
  50         blob_put_int32(&b, UBUS_ATTR_TARGET, id);
  51
  52         if (ubus_start_request(ctx, &req, b.head, type, 0) < 0)
  53                 return UBUS_STATUS_INVALID_ARGUMENT;
  54
  55         return ubus_complete_request(ctx, &req, 0);
  56
  57 }
  58
  59 int ubus_subscribe(struct ubus_context *ctx, struct ubus_subscriber *obj, uint32_t id)
  60 {
  61         return __ubus_subscribe_request(ctx, &obj->obj, id, UBUS_MSG_SUBSCRIBE);
  62 }
  63
  64 int ubus_unsubscribe(struct ubus_context *ctx, struct ubus_subscriber *obj, uint32_t id)
  65 {
  66         return __ubus_subscribe_request(ctx, &obj->obj, id, UBUS_MSG_UNSUBSCRIBE);
  67 }
  68
  69 void __hidden ubus_process_unsubscribe(struct ubus_context *ctx, struct ubus_msghdr *hdr)
  70 {
  71         struct ubus_subscriber *s;
  72         struct blob_attr **attrbuf;
  73         struct ubus_object *obj;
  74         uint32_t objid;
  75
  76         attrbuf = ubus_parse_msg(hdr->data);
  77         if (!attrbuf[UBUS_ATTR_OBJID] || !attrbuf[UBUS_ATTR_TARGET])
  78                 return;
  79
  80         objid = blob_get_u32(attrbuf[UBUS_ATTR_OBJID]);
  81         obj = avl_find_element(&ctx->objects, &objid, obj, avl);
  82         if (!obj)
  83                 return;
  84
  85         if (obj->methods != &watch_method)
  86                 return;
  87
  88         s = container_of(obj, struct ubus_subscriber, obj);
  89         s->remove_cb(ctx, s, blob_get_u32(attrbuf[UBUS_ATTR_TARGET]));
  90 }
  91
  92 void __hidden ubus_process_notify(struct ubus_context *ctx, struct ubus_msghdr *hdr)
  93 {
  94         struct blob_attr **attrbuf;
  95         struct ubus_object *obj;
  96         uint32_t objid;
  97
  98         attrbuf = ubus_parse_msg(hdr->data);
  99         if (!attrbuf[UBUS_ATTR_OBJID] || !attrbuf[UBUS_ATTR_ACTIVE])
 100                 return;
 101
 102         objid = blob_get_u32(attrbuf[UBUS_ATTR_OBJID]);
 103         obj = avl_find_element(&ctx->objects, &objid, obj, avl);
 104         if (!obj)
 105                 return;
 106
 107         obj->has_subscribers = blob_get_u8(attrbuf[UBUS_ATTR_ACTIVE]);
 108         if (obj->subscribe_cb)
 109                 obj->subscribe_cb(ctx, obj);
 110 }