libubus.h

   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 <libubox/avl.h>
  15 #include <libubox/list.h>
  16 #include <libubox/blobmsg.h>
  17 #include <libubox/uloop.h>
  18 #include <stdint.h>
  19 #include "ubusmsg.h"
  20 #include "ubus_common.h"
  21
  22 struct ubus_context;
  23 struct ubus_msg_src;
  24 struct ubus_object;
  25 struct ubus_request;
  26 struct ubus_request_data;
  27 struct ubus_object_data;
  28 struct ubus_event_handler;
  29 struct ubus_watch_object;
  30
  31 typedef void (*ubus_lookup_handler_t)(struct ubus_context *ctx,
  32                                       struct ubus_object_data *obj,
  33                                       void *priv);
  34 typedef int (*ubus_handler_t)(struct ubus_context *ctx, struct ubus_object *obj,
  35                               struct ubus_request_data *req,
  36                               const char *method, struct blob_attr *msg);
  37 typedef void (*ubus_event_handler_t)(struct ubus_context *ctx, struct ubus_event_handler *ev,
  38                                      const char *type, struct blob_attr *msg);
  39 typedef void (*ubus_watch_handler_t)(struct ubus_context *ctx, struct ubus_watch_object *w,
  40                                      uint32_t id);
  41 typedef void (*ubus_data_handler_t)(struct ubus_request *req,
  42                                     int type, struct blob_attr *msg);
  43 typedef void (*ubus_complete_handler_t)(struct ubus_request *req, int ret);
  44
  45 #define UBUS_OBJECT_TYPE(_name, _methods)               \
  46         {                                               \
  47                 .name = _name,                          \
  48                 .id = 0,                                \
  49                 .n_methods = ARRAY_SIZE(_methods),      \
  50                 .methods = _methods                     \
  51         }
  52
  53 #define UBUS_METHOD(_name, _handler, _policy)           \
  54         {                                               \
  55                 .name = _name,                          \
  56                 .handler = _handler,                    \
  57                 .policy = _policy,                      \
  58                 .n_policy = ARRAY_SIZE(_policy)         \
  59         }
  60
  61 struct ubus_method {
  62         const char *name;
  63         ubus_handler_t handler;
  64
  65         const struct blobmsg_policy *policy;
  66         int n_policy;
  67 };
  68
  69 struct ubus_object_type {
  70         const char *name;
  71         uint32_t id;
  72
  73         const struct ubus_method *methods;
  74         int n_methods;
  75 };
  76
  77 struct ubus_object {
  78         struct avl_node avl;
  79
  80         const char *name;
  81         uint32_t id;
  82
  83         const char *path;
  84         struct ubus_object_type *type;
  85
  86         const struct ubus_method *methods;
  87         int n_methods;
  88 };
  89
  90 struct ubus_watch_object {
  91         struct ubus_object obj;
  92
  93         ubus_watch_handler_t cb;
  94 };
  95
  96 struct ubus_event_handler {
  97         struct ubus_object obj;
  98
  99         ubus_event_handler_t cb;
 100 };
 101
 102 struct ubus_context {
 103         struct list_head requests;
 104         struct avl_tree objects;
 105         struct list_head pending;
 106
 107         struct uloop_fd sock;
 108
 109         uint32_t local_id;
 110         uint32_t request_seq;
 111         int stack_depth;
 112
 113         void (*connection_lost)(struct ubus_context *ctx);
 114
 115         struct {
 116                 struct ubus_msghdr hdr;
 117                 char data[UBUS_MAX_MSGLEN];
 118         } msgbuf;
 119 };
 120
 121 struct ubus_object_data {
 122         uint32_t id;
 123         uint32_t type_id;
 124         const char *path;
 125         struct blob_attr *signature;
 126 };
 127
 128 struct ubus_request_data {
 129         uint32_t object;
 130         uint32_t peer;
 131         uint32_t seq;
 132 };
 133
 134 struct ubus_request {
 135         struct list_head list;
 136
 137         struct list_head pending;
 138         bool status_msg;
 139         int status_code;
 140         bool blocked;
 141         bool cancelled;
 142
 143         uint32_t peer;
 144         uint32_t seq;
 145
 146         ubus_data_handler_t raw_data_cb;
 147         ubus_data_handler_t data_cb;
 148         ubus_complete_handler_t complete_cb;
 149
 150         struct ubus_context *ctx;
 151         void *priv;
 152 };
 153
 154
 155 struct ubus_context *ubus_connect(const char *path);
 156 int ubus_reconnect(struct ubus_context *ctx, const char *path);
 157 void ubus_free(struct ubus_context *ctx);
 158
 159 const char *ubus_strerror(int error);
 160
 161 static inline void ubus_add_uloop(struct ubus_context *ctx)
 162 {
 163         uloop_fd_add(&ctx->sock, ULOOP_BLOCKING | ULOOP_READ);
 164 }
 165
 166 /* call this for read events on ctx->sock.fd when not using uloop */
 167 static inline void ubus_handle_event(struct ubus_context *ctx)
 168 {
 169         ctx->sock.cb(&ctx->sock, ULOOP_READ);
 170 }
 171
 172 /* ----------- raw request handling ----------- */
 173
 174 /* wait for a request to complete and return its status */
 175 int ubus_complete_request(struct ubus_context *ctx, struct ubus_request *req,
 176                           int timeout);
 177
 178 /* complete a request asynchronously */
 179 void ubus_complete_request_async(struct ubus_context *ctx,
 180                                  struct ubus_request *req);
 181
 182 /* abort an asynchronous request */
 183 void ubus_abort_request(struct ubus_context *ctx, struct ubus_request *req);
 184
 185 /* ----------- objects ----------- */
 186
 187 int ubus_lookup(struct ubus_context *ctx, const char *path,
 188                 ubus_lookup_handler_t cb, void *priv);
 189
 190 int ubus_lookup_id(struct ubus_context *ctx, const char *path, uint32_t *id);
 191
 192 /* make an object visible to remote connections */
 193 int ubus_add_object(struct ubus_context *ctx, struct ubus_object *obj);
 194
 195 /* remove the object from the ubus connection */
 196 int ubus_remove_object(struct ubus_context *ctx, struct ubus_object *obj);
 197
 198 /* add an object for watching other object state changes */
 199 int ubus_register_watch_object(struct ubus_context *ctx, struct ubus_watch_object *obj);
 200
 201 int ubus_watch_object_add(struct ubus_context *ctx, struct ubus_watch_object *obj, uint32_t id);
 202
 203 int ubus_watch_object_remove(struct ubus_context *ctx, struct ubus_watch_object *obj, uint32_t id);
 204
 205 /* ----------- rpc ----------- */
 206
 207 /* invoke a method on a specific object */
 208 int ubus_invoke(struct ubus_context *ctx, uint32_t obj, const char *method,
 209                 struct blob_attr *msg, ubus_data_handler_t cb, void *priv,
 210                 int timeout);
 211
 212 /* asynchronous version of ubus_invoke() */
 213 int ubus_invoke_async(struct ubus_context *ctx, uint32_t obj, const char *method,
 214                       struct blob_attr *msg, struct ubus_request *req);
 215
 216 /* send a reply to an incoming object method call */
 217 int ubus_send_reply(struct ubus_context *ctx, struct ubus_request_data *req,
 218                     struct blob_attr *msg);
 219
 220 /* ----------- events ----------- */
 221
 222 int ubus_send_event(struct ubus_context *ctx, const char *id,
 223                     struct blob_attr *data);
 224
 225 int ubus_register_event_handler(struct ubus_context *ctx,
 226                                 struct ubus_event_handler *ev,
 227                                 const char *pattern);
 228
 229 static inline int ubus_unregister_event_handler(struct ubus_context *ctx,
 230                                                 struct ubus_event_handler *ev)
 231 {
 232     return ubus_remove_object(ctx, &ev->obj);
 233 }