ubusd_obj.c

   1 /*
   2  * Copyright (C) 2011 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 "ubusd.h"
  15 #include "ubusd_obj.h"
  16
  17 struct avl_tree obj_types;
  18 struct avl_tree objects;
  19 struct avl_tree path;
  20
  21 static void ubus_unref_object_type(struct ubus_object_type *type)
  22 {
  23         struct ubus_method *m;
  24
  25         if (--type->refcount > 0)
  26                 return;
  27
  28         while (!list_empty(&type->methods)) {
  29                 m = list_first_entry(&type->methods, struct ubus_method, list);
  30                 list_del(&m->list);
  31                 free(m);
  32         }
  33
  34         ubus_free_id(&obj_types, &type->id);
  35         free(type);
  36 }
  37
  38 static bool ubus_create_obj_method(struct ubus_object_type *type, struct blob_attr *attr)
  39 {
  40         struct ubus_method *m;
  41         int bloblen = blob_raw_len(attr);
  42
  43         m = calloc(1, sizeof(*m) + bloblen);
  44         if (!m)
  45                 return false;
  46
  47         list_add_tail(&m->list, &type->methods);
  48         memcpy(m->data, attr, bloblen);
  49         m->name = blobmsg_name(m->data);
  50
  51         return true;
  52 }
  53
  54 static struct ubus_object_type *ubus_create_obj_type(struct blob_attr *sig)
  55 {
  56         struct ubus_object_type *type;
  57         struct blob_attr *pos;
  58         int rem;
  59
  60         type = calloc(1, sizeof(*type));
  61         type->refcount = 1;
  62
  63         if (!ubus_alloc_id(&obj_types, &type->id, 0))
  64                 goto error_free;
  65
  66         INIT_LIST_HEAD(&type->methods);
  67
  68         blob_for_each_attr(pos, sig, rem) {
  69                 if (!blobmsg_check_attr(pos, true))
  70                         goto error_unref;
  71
  72                 if (!ubus_create_obj_method(type, pos))
  73                         goto error_unref;
  74         }
  75
  76         return type;
  77
  78 error_unref:
  79         ubus_unref_object_type(type);
  80         return NULL;
  81
  82 error_free:
  83         free(type);
  84         return NULL;
  85 }
  86
  87 static struct ubus_object_type *ubus_get_obj_type(uint32_t obj_id)
  88 {
  89         struct ubus_object_type *type;
  90         struct ubus_id *id;
  91
  92         id = ubus_find_id(&obj_types, obj_id);
  93         if (!id)
  94                 return NULL;
  95
  96         type = container_of(id, struct ubus_object_type, id);
  97         type->refcount++;
  98         return type;
  99 }
 100
 101 struct ubus_object *ubusd_create_object_internal(struct ubus_object_type *type, uint32_t id)
 102 {
 103         struct ubus_object *obj;
 104
 105         obj = calloc(1, sizeof(*obj));
 106         if (!obj)
 107                 return NULL;
 108
 109         if (!ubus_alloc_id(&objects, &obj->id, id))
 110                 goto error_free;
 111
 112         obj->type = type;
 113         INIT_LIST_HEAD(&obj->list);
 114         INIT_LIST_HEAD(&obj->events);
 115         INIT_LIST_HEAD(&obj->subscribers);
 116         INIT_LIST_HEAD(&obj->target_list);
 117         if (type)
 118                 type->refcount++;
 119
 120         return obj;
 121
 122 error_free:
 123         free(obj);
 124         return NULL;
 125 }
 126
 127 struct ubus_object *ubusd_create_object(struct ubus_client *cl, struct blob_attr **attr)
 128 {
 129         struct ubus_object *obj;
 130         struct ubus_object_type *type = NULL;
 131
 132         if (attr[UBUS_ATTR_OBJTYPE])
 133                 type = ubus_get_obj_type(blob_get_u32(attr[UBUS_ATTR_OBJTYPE]));
 134         else if (attr[UBUS_ATTR_SIGNATURE])
 135                 type = ubus_create_obj_type(attr[UBUS_ATTR_SIGNATURE]);
 136
 137         obj = ubusd_create_object_internal(type, 0);
 138         if (type)
 139                 ubus_unref_object_type(type);
 140
 141         if (!obj)
 142                 return NULL;
 143
 144         if (attr[UBUS_ATTR_OBJPATH]) {
 145                 obj->path.key = strdup(blob_data(attr[UBUS_ATTR_OBJPATH]));
 146                 if (!obj->path.key)
 147                         goto free;
 148
 149                 if (avl_insert(&path, &obj->path) != 0) {
 150                         free((void *) obj->path.key);
 151                         obj->path.key = NULL;
 152                         goto free;
 153                 }
 154                 ubusd_send_obj_event(obj, true);
 155         }
 156
 157         obj->client = cl;
 158         list_add(&obj->list, &cl->objects);
 159
 160         return obj;
 161
 162 free:
 163         ubusd_free_object(obj);
 164         return NULL;
 165 }
 166
 167 void ubus_subscribe(struct ubus_object *obj, struct ubus_object *target, const char *method)
 168 {
 169         struct ubus_subscription *s;
 170
 171         s = calloc(1, sizeof(*s) + strlen(method) + 1);
 172         if (!s)
 173                 return;
 174
 175         s->subscriber = obj;
 176         s->target = target;
 177         list_add(&s->list, &target->subscribers);
 178         list_add(&s->target_list, &obj->target_list);
 179         strcpy(s->method, method);
 180 }
 181
 182 void ubus_unsubscribe(struct ubus_subscription *s)
 183 {
 184         list_del(&s->list);
 185         list_del(&s->target_list);
 186         free(s);
 187 }
 188
 189 void ubusd_free_object(struct ubus_object *obj)
 190 {
 191         struct ubus_subscription *s, *tmp;
 192
 193         list_for_each_entry_safe(s, tmp, &obj->target_list, target_list) {
 194                 ubus_unsubscribe(s);
 195         }
 196         list_for_each_entry_safe(s, tmp, &obj->subscribers, list) {
 197                 ubus_notify_unsubscribe(s);
 198         }
 199
 200         ubusd_event_cleanup_object(obj);
 201         if (obj->path.key) {
 202                 ubusd_send_obj_event(obj, false);
 203                 avl_delete(&path, &obj->path);
 204                 free((void *) obj->path.key);
 205         }
 206         if (!list_empty(&obj->list))
 207                 list_del(&obj->list);
 208         ubus_free_id(&objects, &obj->id);
 209         if (obj->type)
 210                 ubus_unref_object_type(obj->type);
 211         free(obj);
 212 }
 213
 214 static void __init ubusd_obj_init(void)
 215 {
 216         ubus_init_id_tree(&objects);
 217         ubus_init_id_tree(&obj_types);
 218         ubus_init_string_tree(&path, false);
 219         ubusd_event_init();
 220 }