lua/ubus.c

   1 /*
   2  * Copyright (C) 2012 Jo-Philipp Wich <jow@openwrt.org>
   3  * Copyright (C) 2012 John Crispin <blogic@openwrt.org>
   4  * Copyright (C) 2016 Iain Fraser <iainf@netduma.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU Lesser General Public License version 2.1
   8  * as published by the Free Software Foundation
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  */
  15
  16 #include <unistd.h>
  17 #include <libubus.h>
  18 #include <libubox/blobmsg.h>
  19 #include <libubox/blobmsg_json.h>
  20 #include <lauxlib.h>
  21 #include <lua.h>
  22
  23 #define MODNAME         "ubus"
  24 #define METANAME        MODNAME ".meta"
  25
  26 static lua_State *state;
  27
  28 struct ubus_lua_connection {
  29         int timeout;
  30         struct blob_buf buf;
  31         struct ubus_context *ctx;
  32 };
  33
  34 struct ubus_lua_object {
  35         struct ubus_object o;
  36         int r;
  37         int rsubscriber;
  38 };
  39
  40 struct ubus_lua_event {
  41         struct ubus_event_handler e;
  42         int r;
  43 };
  44
  45 struct ubus_lua_subscriber {
  46         struct ubus_subscriber s;
  47         int rnotify;
  48         int rremove;
  49 };
  50
  51 static int
  52 ubus_lua_parse_blob(lua_State *L, struct blob_attr *attr, bool table);
  53
  54 static int
  55 ubus_lua_parse_blob_array(lua_State *L, struct blob_attr *attr, int len, bool table)
  56 {
  57         int rv;
  58         int idx = 1;
  59         int rem = len;
  60         struct blob_attr *pos;
  61
  62         lua_newtable(L);
  63
  64         __blob_for_each_attr(pos, attr, rem)
  65         {
  66                 rv = ubus_lua_parse_blob(L, pos, table);
  67
  68                 if (rv > 1)
  69                         lua_rawset(L, -3);
  70                 else if (rv > 0)
  71                         lua_rawseti(L, -2, idx++);
  72         }
  73
  74         return 1;
  75 }
  76
  77 static int
  78 ubus_lua_parse_blob(lua_State *L, struct blob_attr *attr, bool table)
  79 {
  80         int len;
  81         int off = 0;
  82         void *data;
  83
  84         if (!blobmsg_check_attr(attr, false))
  85                 return 0;
  86
  87         if (table && blobmsg_name(attr)[0])
  88         {
  89                 lua_pushstring(L, blobmsg_name(attr));
  90                 off++;
  91         }
  92
  93         data = blobmsg_data(attr);
  94         len = blobmsg_data_len(attr);
  95
  96         switch (blob_id(attr))
  97         {
  98         case BLOBMSG_TYPE_BOOL:
  99                 lua_pushboolean(L, *(uint8_t *)data);
 100                 break;
 101
 102         case BLOBMSG_TYPE_INT16:
 103                 lua_pushinteger(L, be16_to_cpu(*(uint16_t *)data));
 104                 break;
 105
 106         case BLOBMSG_TYPE_INT32:
 107                 lua_pushinteger(L, be32_to_cpu(*(uint32_t *)data));
 108                 break;
 109
 110         case BLOBMSG_TYPE_INT64:
 111                 lua_pushnumber(L, (double) be64_to_cpu(*(uint64_t *)data));
 112                 break;
 113
 114         case BLOBMSG_TYPE_DOUBLE:
 115                 {
 116                         union {
 117                                 double d;
 118                                 uint64_t u64;
 119                         } v;
 120                         v.u64 = be64_to_cpu(*(uint64_t *)data);
 121                         lua_pushnumber(L, v.d);
 122                 }
 123                 break;
 124
 125         case BLOBMSG_TYPE_STRING:
 126                 lua_pushstring(L, data);
 127                 break;
 128
 129         case BLOBMSG_TYPE_ARRAY:
 130                 ubus_lua_parse_blob_array(L, data, len, false);
 131                 break;
 132
 133         case BLOBMSG_TYPE_TABLE:
 134                 ubus_lua_parse_blob_array(L, data, len, true);
 135                 break;
 136
 137         default:
 138                 lua_pushnil(L);
 139                 break;
 140         }
 141
 142         return off + 1;
 143 }
 144
 145
 146 static bool
 147 ubus_lua_format_blob_is_array(lua_State *L)
 148 {
 149         lua_Integer prv = 0;
 150         lua_Integer cur = 0;
 151
 152         /* Find out whether table is array-like */
 153         for (lua_pushnil(L); lua_next(L, -2); lua_pop(L, 1))
 154         {
 155 #ifdef LUA_TINT
 156                 if (lua_type(L, -2) != LUA_TNUMBER && lua_type(L, -2) != LUA_TINT)
 157 #else
 158                 if (lua_type(L, -2) != LUA_TNUMBER)
 159 #endif
 160                 {
 161                         lua_pop(L, 2);
 162                         return false;
 163                 }
 164
 165                 cur = lua_tointeger(L, -2);
 166
 167                 if ((cur - 1) != prv)
 168                 {
 169                         lua_pop(L, 2);
 170                         return false;
 171                 }
 172
 173                 prv = cur;
 174         }
 175
 176         return true;
 177 }
 178
 179 static int
 180 ubus_lua_format_blob_array(lua_State *L, struct blob_buf *b, bool table);
 181
 182 static int
 183 ubus_lua_format_blob(lua_State *L, struct blob_buf *b, bool table)
 184 {
 185         void *c;
 186         bool rv = true;
 187         const char *key = table ? lua_tostring(L, -2) : NULL;
 188
 189         switch (lua_type(L, -1))
 190         {
 191         case LUA_TBOOLEAN:
 192                 blobmsg_add_u8(b, key, (uint8_t)lua_toboolean(L, -1));
 193                 break;
 194
 195 #ifdef LUA_TINT
 196         case LUA_TINT:
 197 #endif
 198         case LUA_TNUMBER:
 199                 blobmsg_add_u32(b, key, (uint32_t)lua_tointeger(L, -1));
 200                 break;
 201
 202         case LUA_TSTRING:
 203         case LUA_TUSERDATA:
 204         case LUA_TLIGHTUSERDATA:
 205                 blobmsg_add_string(b, key, lua_tostring(L, -1));
 206                 break;
 207
 208         case LUA_TTABLE:
 209                 if (ubus_lua_format_blob_is_array(L))
 210                 {
 211                         c = blobmsg_open_array(b, key);
 212                         rv = ubus_lua_format_blob_array(L, b, false);
 213                         blobmsg_close_array(b, c);
 214                 }
 215                 else
 216                 {
 217                         c = blobmsg_open_table(b, key);
 218                         rv = ubus_lua_format_blob_array(L, b, true);
 219                         blobmsg_close_table(b, c);
 220                 }
 221                 break;
 222
 223         default:
 224                 rv = false;
 225                 break;
 226         }
 227
 228         return rv;
 229 }
 230
 231 static int
 232 ubus_lua_format_blob_array(lua_State *L, struct blob_buf *b, bool table)
 233 {
 234         for (lua_pushnil(L); lua_next(L, -2); lua_pop(L, 1))
 235         {
 236                 if (!ubus_lua_format_blob(L, b, table))
 237                 {
 238                         lua_pop(L, 1);
 239                         return false;
 240                 }
 241         }
 242
 243         return true;
 244 }
 245
 246
 247 static int
 248 ubus_lua_connect(lua_State *L)
 249 {
 250         struct ubus_lua_connection *c;
 251         const char *sockpath = luaL_optstring(L, 1, NULL);
 252         int timeout = luaL_optint(L, 2, 30);
 253
 254         if ((c = lua_newuserdata(L, sizeof(*c))) != NULL &&
 255                 (c->ctx = ubus_connect(sockpath)) != NULL)
 256         {
 257                 ubus_add_uloop(c->ctx);
 258                 c->timeout = timeout;
 259                 memset(&c->buf, 0, sizeof(c->buf));
 260                 luaL_getmetatable(L, METANAME);
 261                 lua_setmetatable(L, -2);
 262                 return 1;
 263         }
 264
 265         /* NB: no errors from ubus_connect() yet */
 266         lua_pushnil(L);
 267         lua_pushinteger(L, UBUS_STATUS_UNKNOWN_ERROR);
 268         return 2;
 269 }
 270
 271
 272 static void
 273 ubus_lua_objects_cb(struct ubus_context *c, struct ubus_object_data *o, void *p)
 274 {
 275         lua_State *L = (lua_State *)p;
 276
 277         lua_pushstring(L, o->path);
 278         lua_rawseti(L, -2, lua_objlen(L, -2) + 1);
 279 }
 280
 281 static int
 282 ubus_lua_objects(lua_State *L)
 283 {
 284         int rv;
 285         struct ubus_lua_connection *c = luaL_checkudata(L, 1, METANAME);
 286
 287         lua_newtable(L);
 288         rv = ubus_lookup(c->ctx, NULL, ubus_lua_objects_cb, L);
 289
 290         if (rv != UBUS_STATUS_OK)
 291         {
 292                 lua_pop(L, 1);
 293                 lua_pushnil(L);
 294                 lua_pushinteger(L, rv);
 295                 return 2;
 296         }
 297
 298         return 1;
 299 }
 300
 301 static int
 302 ubus_method_handler(struct ubus_context *ctx, struct ubus_object *obj,
 303                 struct ubus_request_data *req, const char *method,
 304                 struct blob_attr *msg)
 305 {
 306         struct ubus_lua_object *o = container_of(obj, struct ubus_lua_object, o);
 307         int rv = 0;
 308
 309         lua_getglobal(state, "__ubus_cb");
 310         lua_rawgeti(state, -1, o->r);
 311         lua_getfield(state, -1, method);
 312         lua_remove(state, -2);
 313         lua_remove(state, -2);
 314
 315         if (lua_isfunction(state, -1)) {
 316                 lua_pushlightuserdata(state, req);
 317                 if (!msg)
 318                         lua_pushnil(state);
 319                 else
 320                         ubus_lua_parse_blob_array(state, blob_data(msg), blob_len(msg), true);
 321                 lua_call(state, 2, 1);
 322                 if (lua_isnumber(state, -1))
 323                         rv = lua_tonumber(state, -1);
 324         }
 325
 326         lua_pop(state, 1);
 327
 328         return rv;
 329 }
 330
 331 static int lua_gettablelen(lua_State *L, int index)
 332 {
 333         int cnt = 0;
 334
 335         lua_pushnil(L);
 336         index -= 1;
 337         while (lua_next(L, index) != 0) {
 338                 cnt++;
 339                 lua_pop(L, 1);
 340         }
 341
 342         return cnt;
 343 }
 344
 345 static int ubus_lua_reply(lua_State *L)
 346 {
 347         struct ubus_lua_connection *c = luaL_checkudata(L, 1, METANAME);
 348         struct ubus_request_data *req;
 349
 350         luaL_checktype(L, 3, LUA_TTABLE);
 351         blob_buf_init(&c->buf, 0);
 352
 353         if (!ubus_lua_format_blob_array(L, &c->buf, true))
 354         {
 355                 lua_pushnil(L);
 356                 lua_pushinteger(L, UBUS_STATUS_INVALID_ARGUMENT);
 357                 return 2;
 358         }
 359
 360         req = lua_touserdata(L, 2);
 361         ubus_send_reply(c->ctx, req, c->buf.head);
 362
 363         return 0;
 364 }
 365
 366 static int ubus_lua_defer_request(lua_State *L)
 367 {
 368         struct ubus_lua_connection *c = luaL_checkudata(L, 1, METANAME);
 369         struct ubus_request_data *req = lua_touserdata(L, 2);
 370         struct ubus_request_data *new_req = lua_newuserdata(L, sizeof(struct ubus_request_data));
 371         ubus_defer_request(c->ctx, req, new_req);
 372
 373         return 1;
 374 }
 375
 376 static int ubus_lua_complete_deferred_request(lua_State *L)
 377 {
 378         struct ubus_lua_connection *c = luaL_checkudata(L, 1, METANAME);
 379         struct ubus_request_data *req = lua_touserdata(L, 2);
 380         int ret = luaL_checkinteger(L, 3);
 381         ubus_complete_deferred_request(c->ctx, req, ret);
 382
 383         return 0;
 384 }
 385
 386 static int ubus_lua_load_methods(lua_State *L, struct ubus_method *m)
 387 {
 388         struct blobmsg_policy *p;
 389         int plen;
 390         int pidx = 0;
 391
 392         /* get the function pointer */
 393         lua_pushinteger(L, 1);
 394         lua_gettable(L, -2);
 395
 396         /* get the policy table */
 397         lua_pushinteger(L, 2);
 398         lua_gettable(L, -3);
 399
 400         /* check if the method table is valid */
 401         if ((lua_type(L, -2) != LUA_TFUNCTION) ||
 402                         (lua_type(L, -1) != LUA_TTABLE) ||
 403                         lua_objlen(L, -1)) {
 404                 lua_pop(L, 2);
 405                 return 1;
 406         }
 407
 408         /* store function pointer */
 409         lua_pushvalue(L, -2);
 410         lua_setfield(L, -6, lua_tostring(L, -5));
 411
 412         m->name = lua_tostring(L, -4);
 413         m->handler = ubus_method_handler;
 414
 415         plen = lua_gettablelen(L, -1);
 416
 417         /* exit if policy table is empty */
 418         if (!plen) {
 419                 lua_pop(L, 2);
 420                 return 0;
 421         }
 422
 423         /* setup the policy pointers */
 424         p = calloc(plen, sizeof(struct blobmsg_policy));
 425         if (!p)
 426                 return 1;
 427
 428         m->policy = p;
 429         lua_pushnil(L);
 430         while (lua_next(L, -2) != 0) {
 431                 int val = lua_tointeger(L, -1);
 432
 433                 /* check if the policy is valid */
 434                 if ((lua_type(L, -2) != LUA_TSTRING) ||
 435                                 (lua_type(L, -1) != LUA_TNUMBER) ||
 436                                 (val < 0) ||
 437                                 (val > BLOBMSG_TYPE_LAST)) {
 438                         lua_pop(L, 1);
 439                         continue;
 440                 }
 441                 p[pidx].name = lua_tostring(L, -2);
 442                 p[pidx].type = val;
 443                 lua_pop(L, 1);
 444                 pidx++;
 445         }
 446
 447         m->n_policy = pidx;
 448         lua_pop(L, 2);
 449
 450         return 0;
 451 }
 452
 453 static void
 454 ubus_new_sub_cb(struct ubus_context *ctx, struct ubus_object *obj)
 455 {
 456         struct ubus_lua_object *luobj;
 457
 458         luobj = container_of(obj, struct ubus_lua_object, o);
 459
 460         lua_getglobal(state, "__ubus_cb_publisher");
 461         lua_rawgeti(state, -1, luobj->rsubscriber);
 462         lua_remove(state, -2);
 463
 464         if (lua_isfunction(state, -1)) {
 465                 lua_pushnumber(state, luobj->o.has_subscribers );
 466                 lua_call(state, 1, 0);
 467         } else {
 468                 lua_pop(state, 1);
 469         }
 470 }
 471
 472 static void
 473 ubus_lua_load_newsub_cb( lua_State *L, struct ubus_lua_object *obj )
 474 {
 475         /* keep ref to func */
 476         lua_getglobal(L, "__ubus_cb_publisher");
 477         lua_pushvalue(L, -2);
 478         obj->rsubscriber = luaL_ref(L, -2);
 479         lua_pop(L, 1);
 480
 481         /* real callback */
 482         obj->o.subscribe_cb = ubus_new_sub_cb;
 483         return;
 484 }
 485
 486 static struct ubus_object* ubus_lua_load_object(lua_State *L)
 487 {
 488         struct ubus_lua_object *obj = NULL;
 489         int mlen = lua_gettablelen(L, -1);
 490         struct ubus_method *m;
 491         int midx = 0;
 492
 493         /* setup object pointers */
 494         obj = calloc(1, sizeof(struct ubus_lua_object));
 495         if (!obj)
 496                 return NULL;
 497
 498         obj->o.name = lua_tostring(L, -2);
 499
 500         /* setup method pointers */
 501         m = calloc(mlen, sizeof(struct ubus_method));
 502         obj->o.methods = m;
 503
 504         /* setup type pointers */
 505         obj->o.type = calloc(1, sizeof(struct ubus_object_type));
 506         if (!obj->o.type) {
 507                 free(obj);
 508                 return NULL;
 509         }
 510
 511         obj->o.type->name = lua_tostring(L, -2);
 512         obj->o.type->id = 0;
 513         obj->o.type->methods = obj->o.methods;
 514
 515         /* create the callback lookup table */
 516         lua_createtable(L, 1, 0);
 517         lua_getglobal(L, "__ubus_cb");
 518         lua_pushvalue(L, -2);
 519         obj->r = luaL_ref(L, -2);
 520         lua_pop(L, 1);
 521
 522         /* scan each method */
 523         lua_pushnil(L);
 524         while (lua_next(L, -3) != 0) {
 525                 /* check if its the subscriber notification callback */
 526                 if( lua_type( L, -2 ) == LUA_TSTRING &&
 527                                 lua_type( L, -1 ) == LUA_TFUNCTION ){
 528                   if( !strcmp( lua_tostring( L, -2 ), "__subscriber_cb" ) )
 529                           ubus_lua_load_newsub_cb( L, obj );
 530                 }
 531
 532                 /* check if it looks like a method */
 533                 if ((lua_type(L, -2) != LUA_TSTRING) ||
 534                                 (lua_type(L, -1) != LUA_TTABLE) ||
 535                                 !lua_objlen(L, -1)) {
 536                         lua_pop(L, 1);
 537                         continue;
 538                 }
 539
 540                 if (!ubus_lua_load_methods(L, &m[midx]))
 541                         midx++;
 542                 lua_pop(L, 1);
 543         }
 544
 545         obj->o.type->n_methods = obj->o.n_methods = midx;
 546
 547         /* pop the callback table */
 548         lua_pop(L, 1);
 549
 550         return &obj->o;
 551 }
 552
 553 static int ubus_lua_add(lua_State *L)
 554 {
 555         struct ubus_lua_connection *c = luaL_checkudata(L, 1, METANAME);
 556
 557         /* verify top level object */
 558         if (lua_istable(L, 1)) {
 559                 lua_pushstring(L, "you need to pass a table");
 560                 lua_error(L);
 561                 return 0;
 562         }
 563
 564         /* scan each object */
 565         lua_pushnil(L);
 566         while (lua_next(L, -2) != 0) {
 567                 struct ubus_object *obj = NULL;
 568
 569                 /* check if the object has a table of methods */
 570                 if ((lua_type(L, -2) == LUA_TSTRING) && (lua_type(L, -1) == LUA_TTABLE)) {
 571                         obj = ubus_lua_load_object(L);
 572
 573                         if (obj){
 574                                 ubus_add_object(c->ctx, obj);
 575
 576                                 /* allow future reference of ubus obj */
 577                                 lua_pushstring(state,"__ubusobj");
 578                                 lua_pushlightuserdata(state, obj);
 579                                 lua_settable(state,-3);
 580                         }
 581                 }
 582                 lua_pop(L, 1);
 583         }
 584
 585         return 0;
 586 }
 587
 588 static int
 589 ubus_lua_notify( lua_State *L )
 590 {
 591         struct ubus_lua_connection *c;
 592         struct ubus_object *obj;
 593         const char* method;
 594
 595         c = luaL_checkudata(L, 1, METANAME);
 596         method = luaL_checkstring(L, 3);
 597         luaL_checktype(L, 4, LUA_TTABLE);
 598
 599         if( !lua_islightuserdata( L, 2 ) ){
 600                 lua_pushfstring( L, "Invald 2nd parameter, expected ubus obj ref" );
 601                 lua_error( L );
 602         }
 603         obj = lua_touserdata( L, 2 );
 604
 605         /* create parameters from table */
 606         blob_buf_init(&c->buf, 0);
 607         if( !ubus_lua_format_blob_array( L, &c->buf, true ) ){
 608                 lua_pushfstring( L, "Invalid 4th parameter, expected table of arguments" );
 609                 lua_error( L );
 610         }
 611
 612         ubus_notify( c->ctx, obj, method, c->buf.head, -1 );
 613         return 0;
 614 }
 615
 616 static void
 617 ubus_lua_signatures_cb(struct ubus_context *c, struct ubus_object_data *o, void *p)
 618 {
 619         lua_State *L = (lua_State *)p;
 620
 621         if (!o->signature)
 622                 return;
 623
 624         ubus_lua_parse_blob_array(L, blob_data(o->signature), blob_len(o->signature), true);
 625 }
 626
 627 static int
 628 ubus_lua_signatures(lua_State *L)
 629 {
 630         int rv;
 631         struct ubus_lua_connection *c = luaL_checkudata(L, 1, METANAME);
 632         const char *path = luaL_checkstring(L, 2);
 633
 634         rv = ubus_lookup(c->ctx, path, ubus_lua_signatures_cb, L);
 635
 636         if (rv != UBUS_STATUS_OK)
 637         {
 638                 lua_pop(L, 1);
 639                 lua_pushnil(L);
 640                 lua_pushinteger(L, rv);
 641                 return 2;
 642         }
 643
 644         return 1;
 645 }
 646
 647
 648 static void
 649 ubus_lua_call_cb(struct ubus_request *req, int type, struct blob_attr *msg)
 650 {
 651         lua_State *L = (lua_State *)req->priv;
 652
 653         if (!msg && L)
 654                 lua_pushnil(L);
 655
 656         if (msg && L)
 657                 ubus_lua_parse_blob_array(L, blob_data(msg), blob_len(msg), true);
 658 }
 659
 660 static int
 661 ubus_lua_call(lua_State *L)
 662 {
 663         int rv, top;
 664         uint32_t id;
 665         struct ubus_lua_connection *c = luaL_checkudata(L, 1, METANAME);
 666         const char *path = luaL_checkstring(L, 2);
 667         const char *func = luaL_checkstring(L, 3);
 668
 669         luaL_checktype(L, 4, LUA_TTABLE);
 670         blob_buf_init(&c->buf, 0);
 671
 672         if (!ubus_lua_format_blob_array(L, &c->buf, true))
 673         {
 674                 lua_pushnil(L);
 675                 lua_pushinteger(L, UBUS_STATUS_INVALID_ARGUMENT);
 676                 return 2;
 677         }
 678
 679         rv = ubus_lookup_id(c->ctx, path, &id);
 680
 681         if (rv)
 682         {
 683                 lua_pushnil(L);
 684                 lua_pushinteger(L, rv);
 685                 return 2;
 686         }
 687
 688         top = lua_gettop(L);
 689         rv = ubus_invoke(c->ctx, id, func, c->buf.head, ubus_lua_call_cb, L, c->timeout * 1000);
 690
 691         if (rv != UBUS_STATUS_OK)
 692         {
 693                 lua_pop(L, 1);
 694                 lua_pushnil(L);
 695                 lua_pushinteger(L, rv);
 696                 return 2;
 697         }
 698
 699         return lua_gettop(L) - top;
 700 }
 701
 702 static void
 703 ubus_event_handler(struct ubus_context *ctx, struct ubus_event_handler *ev,
 704                         const char *type, struct blob_attr *msg)
 705 {
 706         struct ubus_lua_event *listener = container_of(ev, struct ubus_lua_event, e);
 707
 708         lua_getglobal(state, "__ubus_cb_event");
 709         lua_rawgeti(state, -1, listener->r);
 710         lua_remove(state, -2);
 711
 712         if (lua_isfunction(state, -1)) {
 713                 ubus_lua_parse_blob_array(state, blob_data(msg), blob_len(msg), true);
 714                 lua_call(state, 1, 0);
 715         } else {
 716                 lua_pop(state, 1);
 717         }
 718 }
 719
 720 static struct ubus_event_handler*
 721 ubus_lua_load_event(lua_State *L)
 722 {
 723         struct ubus_lua_event* event = NULL;
 724
 725         event = calloc(1, sizeof(struct ubus_lua_event));
 726         if (!event)
 727                 return NULL;
 728
 729         event->e.cb = ubus_event_handler;
 730
 731         /* update the he callback lookup table */
 732         lua_getglobal(L, "__ubus_cb_event");
 733         lua_pushvalue(L, -2);
 734         event->r = luaL_ref(L, -2);
 735         lua_setfield(L, -1, lua_tostring(L, -3));
 736
 737         return &event->e;
 738 }
 739
 740 static int
 741 ubus_lua_listen(lua_State *L) {
 742         struct ubus_lua_connection *c = luaL_checkudata(L, 1, METANAME);
 743
 744         /* verify top level object */
 745         luaL_checktype(L, 2, LUA_TTABLE);
 746
 747         /* scan each object */
 748         lua_pushnil(L);
 749         while (lua_next(L, -2) != 0) {
 750                 struct ubus_event_handler *listener;
 751
 752                 /* check if the key is a string and the value is a method */
 753                 if ((lua_type(L, -2) == LUA_TSTRING) && (lua_type(L, -1) == LUA_TFUNCTION)) {
 754                         listener = ubus_lua_load_event(L);
 755                         if(listener != NULL) {
 756                                 ubus_register_event_handler(c->ctx, listener, lua_tostring(L, -2));
 757                         }
 758                 }
 759                 lua_pop(L, 1);
 760         }
 761         return 0;
 762 }
 763
 764 static void
 765 ubus_sub_remove_handler(struct ubus_context *ctx, struct ubus_subscriber *s,
 766                             uint32_t id)
 767 {
 768         struct ubus_lua_subscriber *sub;
 769
 770         sub = container_of(s, struct ubus_lua_subscriber, s);
 771
 772         lua_getglobal(state, "__ubus_cb_subscribe");
 773         lua_rawgeti(state, -1, sub->rremove);
 774         lua_remove(state, -2);
 775
 776         if (lua_isfunction(state, -1)) {
 777                 lua_call(state, 0, 0);
 778         } else {
 779                 lua_pop(state, 1);
 780         }
 781 }
 782
 783 static int
 784 ubus_sub_notify_handler(struct ubus_context *ctx, struct ubus_object *obj,
 785             struct ubus_request_data *req, const char *method,
 786             struct blob_attr *msg)
 787 {
 788         struct ubus_subscriber *s;
 789         struct ubus_lua_subscriber *sub;
 790
 791         s = container_of(obj, struct ubus_subscriber, obj);
 792         sub = container_of(s, struct ubus_lua_subscriber, s);
 793
 794         lua_getglobal(state, "__ubus_cb_subscribe");
 795         lua_rawgeti(state, -1, sub->rnotify);
 796         lua_remove(state, -2);
 797
 798         if (lua_isfunction(state, -1)) {
 799                 if( msg ){
 800                         ubus_lua_parse_blob_array(state, blob_data(msg), blob_len(msg), true);
 801                 } else {
 802                         lua_pushnil(state);
 803                 }
 804                 lua_pushstring(state, method);
 805                 lua_call(state, 2, 0);
 806         } else {
 807                 lua_pop(state, 1);
 808         }
 809
 810         return 0;
 811 }
 812
 813
 814
 815 static void
 816 ubus_lua_do_subscribe( struct ubus_context *ctx, lua_State *L, const char* target,
 817                         int idxnotify, int idxremove )
 818 {
 819         uint32_t id;
 820         int status;
 821         struct ubus_lua_subscriber *sub;
 822
 823         if( ( status = ubus_lookup_id( ctx, target, &id ) ) ){
 824                 lua_pushfstring( L, "Unable find target, status=%d", status );
 825                 lua_error( L );
 826         }
 827
 828         sub = calloc( 1, sizeof( struct ubus_lua_subscriber ) );
 829         if( !sub ){
 830                 lua_pushstring( L, "Out of memory" );
 831                 lua_error( L );
 832         }
 833
 834         if( idxnotify ){
 835                 lua_getglobal(L, "__ubus_cb_subscribe");
 836                 lua_pushvalue(L, idxnotify);
 837                 sub->rnotify = luaL_ref(L, -2);
 838                 lua_pop(L, 1);
 839                 sub->s.cb = ubus_sub_notify_handler;
 840         }
 841
 842         if( idxremove ){
 843                 lua_getglobal(L, "__ubus_cb_subscribe");
 844                 lua_pushvalue(L, idxnotify);
 845                 sub->rnotify = luaL_ref(L, -2);
 846                 lua_pop(L, 1);
 847                 sub->s.remove_cb = ubus_sub_remove_handler;
 848         }
 849
 850         if( ( status = ubus_register_subscriber( ctx, &sub->s ) ) ){
 851                 lua_pushfstring( L, "Failed to register subscriber, status=%d", status );
 852                 lua_error( L );
 853         }
 854
 855         if( ( status = ubus_subscribe( ctx, &sub->s, id) ) ){
 856                 lua_pushfstring( L, "Failed to register subscriber, status=%d", status );
 857                 lua_error( L );
 858         }
 859 }
 860
 861 static int
 862 ubus_lua_subscribe(lua_State *L) {
 863         int idxnotify, idxremove, stackstart;
 864         struct ubus_lua_connection *c;
 865         const char* target;
 866
 867         idxnotify = idxremove = 0;
 868         stackstart = lua_gettop( L );
 869
 870
 871         c = luaL_checkudata(L, 1, METANAME);
 872         target = luaL_checkstring(L, 2);
 873         luaL_checktype(L, 3, LUA_TTABLE);
 874
 875
 876         lua_pushstring( L, "notify");
 877         lua_gettable( L, 3 );
 878         if( lua_type( L, -1 ) == LUA_TFUNCTION ){
 879                 idxnotify = lua_gettop( L );
 880         } else {
 881                 lua_pop( L, 1 );
 882         }
 883
 884         lua_pushstring( L, "remove");
 885         lua_gettable( L, 3 );
 886         if( lua_type( L, -1 ) == LUA_TFUNCTION ){
 887                 idxremove = lua_gettop( L );
 888         } else {
 889                 lua_pop( L, 1 );
 890         }
 891
 892         if( idxnotify )
 893                 ubus_lua_do_subscribe( c->ctx, L, target, idxnotify, idxremove );
 894
 895         if( lua_gettop( L ) > stackstart )
 896                 lua_pop( L, lua_gettop( L ) - stackstart );
 897
 898         return 0;
 899 }
 900
 901 static int
 902 ubus_lua_send(lua_State *L)
 903 {
 904         struct ubus_lua_connection *c = luaL_checkudata(L, 1, METANAME);
 905         const char *event = luaL_checkstring(L, 2);
 906
 907         if (*event == 0)
 908                 return luaL_argerror(L, 2, "no event name");
 909
 910         // Event content convert to ubus form
 911         luaL_checktype(L, 3, LUA_TTABLE);
 912         blob_buf_init(&c->buf, 0);
 913
 914         if (!ubus_lua_format_blob_array(L, &c->buf, true)) {
 915                 lua_pushnil(L);
 916                 lua_pushinteger(L, UBUS_STATUS_INVALID_ARGUMENT);
 917                 return 2;
 918         }
 919
 920         // Send the event
 921         ubus_send_event(c->ctx, event, c->buf.head);
 922
 923         return 0;
 924 }
 925
 926
 927
 928 static int
 929 ubus_lua__gc(lua_State *L)
 930 {
 931         struct ubus_lua_connection *c = luaL_checkudata(L, 1, METANAME);
 932
 933         blob_buf_free(&c->buf);
 934         if (c->ctx != NULL)
 935         {
 936                 ubus_free(c->ctx);
 937                 memset(c, 0, sizeof(*c));
 938         }
 939
 940         return 0;
 941 }
 942
 943 static const luaL_Reg ubus[] = {
 944         { "connect", ubus_lua_connect },
 945         { "objects", ubus_lua_objects },
 946         { "add", ubus_lua_add },
 947         { "notify", ubus_lua_notify },
 948         { "reply", ubus_lua_reply },
 949         { "defer_request", ubus_lua_defer_request },
 950         { "complete_deferred_request", ubus_lua_complete_deferred_request },
 951         { "signatures", ubus_lua_signatures },
 952         { "call", ubus_lua_call },
 953         { "close", ubus_lua__gc },
 954         { "listen", ubus_lua_listen },
 955         { "send", ubus_lua_send },
 956         { "subscribe", ubus_lua_subscribe },
 957         { "__gc", ubus_lua__gc },
 958         { NULL, NULL },
 959 };
 960
 961 /* avoid missing prototype warning */
 962 int luaopen_ubus(lua_State *L);
 963
 964 int
 965 luaopen_ubus(lua_State *L)
 966 {
 967         /* create metatable */
 968         luaL_newmetatable(L, METANAME);
 969
 970         /* metatable.__index = metatable */
 971         lua_pushvalue(L, -1);
 972         lua_setfield(L, -2, "__index");
 973
 974         /* fill metatable */
 975         luaL_register(L, NULL, ubus);
 976         lua_pop(L, 1);
 977
 978         /* create module */
 979         luaL_register(L, MODNAME, ubus);
 980
 981         /* set some enum defines */
 982         lua_pushinteger(L, BLOBMSG_TYPE_ARRAY);
 983         lua_setfield(L, -2, "ARRAY");
 984         lua_pushinteger(L, BLOBMSG_TYPE_TABLE);
 985         lua_setfield(L, -2, "TABLE");
 986         lua_pushinteger(L, BLOBMSG_TYPE_STRING);
 987         lua_setfield(L, -2, "STRING");
 988         lua_pushinteger(L, BLOBMSG_TYPE_INT64);
 989         lua_setfield(L, -2, "INT64");
 990         lua_pushinteger(L, BLOBMSG_TYPE_INT32);
 991         lua_setfield(L, -2, "INT32");
 992         lua_pushinteger(L, BLOBMSG_TYPE_INT16);
 993         lua_setfield(L, -2, "INT16");
 994         lua_pushinteger(L, BLOBMSG_TYPE_INT8);
 995         lua_setfield(L, -2, "INT8");
 996         lua_pushinteger(L, BLOBMSG_TYPE_DOUBLE);
 997         lua_setfield(L, -2, "DOUBLE");
 998         lua_pushinteger(L, BLOBMSG_TYPE_BOOL);
 999         lua_setfield(L, -2, "BOOLEAN");
1000
1001         /* used in our callbacks */
1002         state = L;
1003
1004         /* create the callback table */
1005         lua_createtable(L, 1, 0);
1006         lua_setglobal(L, "__ubus_cb");
1007
1008         /* create the event table */
1009         lua_createtable(L, 1, 0);
1010         lua_setglobal(L, "__ubus_cb_event");
1011
1012         /* create the subscriber table */
1013         lua_createtable(L, 1, 0);
1014         lua_setglobal(L, "__ubus_cb_subscribe");
1015
1016         /* create the publisher table - notifications of new subs */
1017         lua_createtable(L, 1, 0);
1018         lua_setglobal(L, "__ubus_cb_publisher");
1019         return 0;
1020 }