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