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