lua/uci.c

   1 /*
   2  * libuci plugin for Lua
   3  * Copyright (C) 2008 Felix Fietkau <nbd@openwrt.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2
   7  * as published by the Free Software Foundation
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include <sys/types.h>
  16 #include <sys/time.h>
  17 #include <stdbool.h>
  18 #include <stdlib.h>
  19 #include <string.h>
  20 #include <unistd.h>
  21 #include <stdio.h>
  22 #include <errno.h>
  23
  24 #include <lauxlib.h>
  25 #include <uci.h>
  26
  27 #define MODNAME        "uci"
  28 #define METANAME       MODNAME ".meta"
  29 //#define DEBUG 1
  30
  31 #ifdef DEBUG
  32 #define DPRINTF(...) fprintf(stderr, __VA_ARGS__)
  33 #else
  34 #define DPRINTF(...) do {} while (0)
  35 #endif
  36
  37 static struct uci_context *global_ctx = NULL;
  38
  39 static struct uci_context *
  40 find_context(lua_State *L, int *offset)
  41 {
  42         struct uci_context **ctx;
  43         if (!lua_isuserdata(L, 1)) {
  44                 if (!global_ctx) {
  45                         global_ctx = uci_alloc_context();
  46                         if (!global_ctx)
  47                                 luaL_error(L, "failed to allocate UCI context");
  48                 }
  49                 if (offset)
  50                         *offset = 0;
  51                 return global_ctx;
  52         }
  53         if (offset)
  54                 *offset = 1;
  55         ctx = luaL_checkudata(L, 1, METANAME);
  56         if (!ctx || !*ctx)
  57                 luaL_error(L, "failed to get UCI context");
  58
  59         return *ctx;
  60 }
  61
  62 static struct uci_package *
  63 find_package(lua_State *L, struct uci_context *ctx, const char *str, bool al)
  64 {
  65         struct uci_package *p = NULL;
  66         struct uci_element *e;
  67         char *sep;
  68         char *name;
  69
  70         sep = strchr(str, '.');
  71         if (sep) {
  72                 name = malloc(1 + sep - str);
  73                 if (!name)
  74                         luaL_error(L, "out of memory");
  75                 strncpy(name, str, sep - str);
  76                 name[sep - str] = 0;
  77         } else
  78                 name = (char *) str;
  79
  80         uci_foreach_element(&ctx->root, e) {
  81                 if (strcmp(e->name, name) != 0)
  82                         continue;
  83
  84                 p = uci_to_package(e);
  85                 goto done;
  86         }
  87
  88         if (al == true)
  89                 uci_load(ctx, name, &p);
  90         else if (al) {
  91                 uci_load(ctx, name, &p);
  92         }
  93
  94 done:
  95         if (name != str)
  96                 free(name);
  97         return p;
  98 }
  99
 100 static int
 101 lookup_args(lua_State *L, struct uci_context *ctx, int offset, struct uci_ptr *ptr, char **buf)
 102 {
 103         char *s = NULL;
 104         int n;
 105
 106         n = lua_gettop(L);
 107         luaL_checkstring(L, 1 + offset);
 108         s = strdup(lua_tostring(L, 1 + offset));
 109         if (!s)
 110                 goto error;
 111
 112         memset(ptr, 0, sizeof(struct uci_ptr));
 113         if (!find_package(L, ctx, s, true))
 114                 goto error;
 115
 116         switch (n - offset) {
 117         case 4:
 118         case 3:
 119                 ptr->option = luaL_checkstring(L, 3 + offset);
 120                 /* fall through */
 121         case 2:
 122                 ptr->section = luaL_checkstring(L, 2 + offset);
 123                 ptr->package = luaL_checkstring(L, 1 + offset);
 124                 if (uci_lookup_ptr(ctx, ptr, NULL, false) != UCI_OK)
 125                         goto error;
 126                 break;
 127         case 1:
 128                 if (uci_lookup_ptr(ctx, ptr, s, false) != UCI_OK)
 129                         goto error;
 130                 break;
 131         default:
 132                 luaL_error(L, "invalid argument count");
 133                 goto error;
 134         }
 135
 136         *buf = s;
 137         return 0;
 138
 139 error:
 140         if (s)
 141                 free(s);
 142         return 1;
 143 }
 144
 145 static int
 146 uci_push_status(lua_State *L, struct uci_context *ctx, bool hasarg)
 147 {
 148         char *str = NULL;
 149
 150         if (!hasarg)
 151                 lua_pushboolean(L, (ctx->err == UCI_OK));
 152         if (ctx->err) {
 153                 uci_get_errorstr(ctx, &str, MODNAME);
 154                 if (str) {
 155                         lua_pushstring(L, str);
 156                         free(str);
 157                         return 2;
 158                 }
 159         }
 160         return 1;
 161 }
 162
 163 static void
 164 uci_push_option(lua_State *L, struct uci_option *o)
 165 {
 166         struct uci_element *e;
 167         int i = 0;
 168
 169         switch(o->type) {
 170         case UCI_TYPE_STRING:
 171                 lua_pushstring(L, o->v.string);
 172                 break;
 173         case UCI_TYPE_LIST:
 174                 lua_newtable(L);
 175                 uci_foreach_element(&o->v.list, e) {
 176                         i++;
 177                         lua_pushstring(L, e->name);
 178                         lua_rawseti(L, -2, i);
 179                 }
 180                 break;
 181         default:
 182                 lua_pushnil(L);
 183                 break;
 184         }
 185 }
 186
 187 static void
 188 uci_push_section(lua_State *L, struct uci_section *s)
 189 {
 190         struct uci_element *e;
 191
 192         lua_newtable(L);
 193         lua_pushboolean(L, s->anonymous);
 194         lua_setfield(L, -2, ".anonymous");
 195         lua_pushstring(L, s->type);
 196         lua_setfield(L, -2, ".type");
 197         lua_pushstring(L, s->e.name);
 198         lua_setfield(L, -2, ".name");
 199
 200         uci_foreach_element(&s->options, e) {
 201                 struct uci_option *o = uci_to_option(e);
 202                 uci_push_option(L, o);
 203                 lua_setfield(L, -2, o->e.name);
 204         }
 205 }
 206
 207 static void
 208 uci_push_package(lua_State *L, struct uci_package *p)
 209 {
 210         struct uci_element *e;
 211         int i = 0;
 212
 213         lua_newtable(L);
 214         uci_foreach_element(&p->sections, e) {
 215                 i++;
 216                 uci_push_section(L, uci_to_section(e));
 217                 lua_setfield(L, -2, e->name);
 218         }
 219 }
 220
 221 static int
 222 uci_lua_unload(lua_State *L)
 223 {
 224         struct uci_context *ctx;
 225         struct uci_package *p;
 226         const char *s;
 227         int offset = 0;
 228
 229         ctx = find_context(L, &offset);
 230         luaL_checkstring(L, 1 + offset);
 231         s = lua_tostring(L, 1 + offset);
 232         p = find_package(L, ctx, s, false);
 233         if (p) {
 234                 uci_unload(ctx, p);
 235                 return uci_push_status(L, ctx, false);
 236         } else {
 237                 lua_pushboolean(L, 0);
 238         }
 239         return 1;
 240 }
 241
 242 static int
 243 uci_lua_load(lua_State *L)
 244 {
 245         struct uci_context *ctx;
 246         struct uci_package *p = NULL;
 247         const char *s;
 248         int offset = 0;
 249
 250         ctx = find_context(L, &offset);
 251         uci_lua_unload(L);
 252         lua_pop(L, 1); /* bool ret value of unload */
 253         s = lua_tostring(L, -1);
 254
 255         uci_load(ctx, s, &p);
 256         return uci_push_status(L, ctx, false);
 257 }
 258
 259
 260 static int
 261 uci_lua_foreach(lua_State *L)
 262 {
 263         struct uci_context *ctx;
 264         struct uci_package *p;
 265         struct uci_element *e;
 266         const char *package, *type;
 267         bool ret = false;
 268         int offset = 0;
 269
 270         ctx = find_context(L, &offset);
 271         package = luaL_checkstring(L, 1 + offset);
 272
 273         if (lua_isnil(L, 2))
 274                 type = NULL;
 275         else
 276                 type = luaL_checkstring(L, 2 + offset);
 277
 278         if (!lua_isfunction(L, 3 + offset) || !package)
 279                 luaL_error(L, "Invalid argument");
 280
 281         p = find_package(L, ctx, package, true);
 282         if (!p)
 283                 goto done;
 284
 285         uci_foreach_element(&p->sections, e) {
 286                 struct uci_section *s = uci_to_section(e);
 287
 288                 if (type && (strcmp(s->type, type) != 0))
 289                         continue;
 290
 291                 lua_pushvalue(L, 3 + offset); /* iterator function */
 292                 uci_push_section(L, s);
 293                 if (lua_pcall(L, 1, 0, 0) == 0)
 294                         ret = true;
 295         }
 296
 297 done:
 298         lua_pushboolean(L, ret);
 299         return 1;
 300 }
 301
 302 static int
 303 uci_lua_get_any(lua_State *L, bool all)
 304 {
 305         struct uci_context *ctx;
 306         struct uci_element *e = NULL;
 307         struct uci_ptr ptr;
 308         int offset = 0;
 309         char *s = NULL;
 310         int err = UCI_ERR_NOTFOUND;
 311
 312         ctx = find_context(L, &offset);
 313
 314         if (lookup_args(L, ctx, offset, &ptr, &s))
 315                 goto error;
 316
 317         uci_lookup_ptr(ctx, &ptr, NULL, false);
 318         if (!all && !ptr.s) {
 319                 err = UCI_ERR_INVAL;
 320                 goto error;
 321         }
 322         if (!(ptr.flags & UCI_LOOKUP_COMPLETE)) {
 323                 err = UCI_ERR_NOTFOUND;
 324                 goto error;
 325         }
 326
 327         err = UCI_OK;
 328         e = ptr.last;
 329         switch(e->type) {
 330                 case UCI_TYPE_PACKAGE:
 331                         uci_push_package(L, ptr.p);
 332                         break;
 333                 case UCI_TYPE_SECTION:
 334                         if (all)
 335                                 uci_push_section(L, ptr.s);
 336                         else
 337                                 lua_pushstring(L, ptr.s->type);
 338                         break;
 339                 case UCI_TYPE_OPTION:
 340                         uci_push_option(L, ptr.o);
 341                         break;
 342                 default:
 343                         err = UCI_ERR_INVAL;
 344                         goto error;
 345         }
 346         if (!err)
 347                 return 1;
 348
 349 error:
 350         if (s)
 351                 free(s);
 352
 353         lua_pushnil(L);
 354         return uci_push_status(L, ctx, true);
 355 }
 356
 357 static int
 358 uci_lua_get(lua_State *L)
 359 {
 360         return uci_lua_get_any(L, false);
 361 }
 362
 363 static int
 364 uci_lua_get_all(lua_State *L)
 365 {
 366         return uci_lua_get_any(L, true);
 367 }
 368
 369 static int
 370 uci_lua_add(lua_State *L)
 371 {
 372         struct uci_context *ctx;
 373         struct uci_section *s = NULL;
 374         struct uci_package *p;
 375         const char *package;
 376         const char *type;
 377         const char *name = NULL;
 378         int offset = 0;
 379
 380         ctx = find_context(L, &offset);
 381         package = luaL_checkstring(L, 1 + offset);
 382         type = luaL_checkstring(L, 2 + offset);
 383         p = find_package(L, ctx, package, true);
 384         if (!p)
 385                 goto fail;
 386
 387         if (uci_add_section(ctx, p, type, &s) || !s)
 388                 goto fail;
 389
 390         name = s->e.name;
 391         lua_pushstring(L, name);
 392         return 1;
 393
 394 fail:
 395         lua_pushnil(L);
 396         return uci_push_status(L, ctx, true);
 397 }
 398
 399 static int
 400 uci_lua_delete(lua_State *L)
 401 {
 402         struct uci_context *ctx;
 403         struct uci_ptr ptr;
 404         int offset = 0;
 405         char *s = NULL;
 406         int err = UCI_ERR_NOTFOUND;
 407
 408         ctx = find_context(L, &offset);
 409
 410         if (lookup_args(L, ctx, offset, &ptr, &s))
 411                 goto error;
 412
 413         err = uci_delete(ctx, &ptr);
 414
 415 error:
 416         if (s)
 417                 free(s);
 418         return uci_push_status(L, ctx, false);
 419 }
 420
 421 static int
 422 uci_lua_set(lua_State *L)
 423 {
 424         struct uci_context *ctx;
 425         struct uci_ptr ptr;
 426         bool istable = false;
 427         int err = UCI_ERR_MEM;
 428         char *s = NULL;
 429         int i, nargs, offset = 0;
 430
 431         ctx = find_context(L, &offset);
 432         nargs = lua_gettop(L);
 433         if (lookup_args(L, ctx, offset, &ptr, &s))
 434                 goto error;
 435
 436         switch(nargs - offset) {
 437         case 1:
 438                 /* Format: uci.set("p.s.o=v") or uci.set("p.s=v") */
 439                 break;
 440         case 4:
 441                 /* Format: uci.set("p", "s", "o", "v") */
 442                 if (lua_istable(L, nargs)) {
 443                         if (lua_objlen(L, nargs) < 1)
 444                                 luaL_error(L, "Cannot set an uci option to an empty table value");
 445                         lua_rawgeti(L, nargs, 1);
 446                         ptr.value = luaL_checkstring(L, -1);
 447                         lua_pop(L, 1);
 448                         istable = true;
 449                 } else {
 450                         ptr.value = luaL_checkstring(L, nargs);
 451                 }
 452                 break;
 453         case 3:
 454                 /* Format: uci.set("p", "s", "v") */
 455                 ptr.value = ptr.option;
 456                 ptr.option = NULL;
 457                 break;
 458         default:
 459                 err = UCI_ERR_INVAL;
 460                 goto error;
 461         }
 462
 463         err = uci_lookup_ptr(ctx, &ptr, NULL, false);
 464         if (err)
 465                 goto error;
 466
 467         if (((ptr.s == NULL) && (ptr.option != NULL)) || (ptr.value == NULL)) {
 468                 err = UCI_ERR_INVAL;
 469                 goto error;
 470         }
 471
 472         err = uci_set(ctx, &ptr);
 473         if (err)
 474                 goto error;
 475
 476         if (istable) {
 477                 for (i = 2; i <= lua_objlen(L, nargs); i++) {
 478                         lua_rawgeti(L, nargs, i);
 479                         ptr.value = luaL_checkstring(L, -1);
 480                         err = uci_add_list(ctx, &ptr);
 481                         lua_pop(L, 1);
 482                         if (err)
 483                                 goto error;
 484                 }
 485         }
 486
 487 error:
 488         return uci_push_status(L, ctx, false);
 489 }
 490
 491 enum pkg_cmd {
 492         CMD_SAVE,
 493         CMD_COMMIT,
 494         CMD_REVERT
 495 };
 496
 497 static int
 498 uci_lua_package_cmd(lua_State *L, enum pkg_cmd cmd)
 499 {
 500         struct uci_context *ctx;
 501         struct uci_element *e, *tmp;
 502         struct uci_ptr ptr;
 503         char *s = NULL;
 504         int failed = 0;
 505         int nargs, offset = 0;
 506
 507         ctx = find_context(L, &offset);
 508         nargs = lua_gettop(L);
 509         if ((cmd != CMD_REVERT) && (nargs > 1))
 510                 goto err;
 511
 512         if (lookup_args(L, ctx, offset, &ptr, &s))
 513                 goto err;
 514
 515         uci_lookup_ptr(ctx, &ptr, NULL, false);
 516
 517         uci_foreach_element_safe(&ctx->root, tmp, e) {
 518                 struct uci_package *p = uci_to_package(e);
 519                 int ret = UCI_ERR_INVAL;
 520
 521                 if (ptr.p && (ptr.p != p))
 522                         continue;
 523
 524                 ptr.p = p;
 525                 switch(cmd) {
 526                 case CMD_COMMIT:
 527                         ret = uci_commit(ctx, &p, false);
 528                         break;
 529                 case CMD_SAVE:
 530                         ret = uci_save(ctx, p);
 531                         break;
 532                 case CMD_REVERT:
 533                         ret = uci_revert(ctx, &ptr);
 534                         break;
 535                 }
 536
 537                 if (ret != 0)
 538                         failed = 1;
 539         }
 540
 541 err:
 542         return uci_push_status(L, ctx, false);
 543 }
 544
 545 static int
 546 uci_lua_save(lua_State *L)
 547 {
 548         return uci_lua_package_cmd(L, CMD_SAVE);
 549 }
 550
 551 static int
 552 uci_lua_commit(lua_State *L)
 553 {
 554         return uci_lua_package_cmd(L, CMD_COMMIT);
 555 }
 556
 557 static int
 558 uci_lua_revert(lua_State *L)
 559 {
 560         return uci_lua_package_cmd(L, CMD_REVERT);
 561 }
 562
 563 static void
 564 uci_lua_add_change(lua_State *L, struct uci_element *e)
 565 {
 566         struct uci_history *h;
 567         const char *name;
 568
 569         h = uci_to_history(e);
 570         if (!h->section)
 571                 return;
 572
 573         lua_getfield(L, -1, h->section);
 574         if (lua_isnil(L, -1)) {
 575                 lua_pop(L, 1);
 576                 lua_newtable(L);
 577                 lua_pushvalue(L, -1); /* copy for setfield */
 578                 lua_setfield(L, -3, h->section);
 579         }
 580
 581         name = (h->e.name ? h->e.name : ".type");
 582         if (h->value)
 583                 lua_pushstring(L, h->value);
 584         else
 585                 lua_pushstring(L, "");
 586         lua_setfield(L, -2, name);
 587         lua_pop(L, 1);
 588 }
 589
 590 static void
 591 uci_lua_changes_pkg(lua_State *L, struct uci_context *ctx, const char *package)
 592 {
 593         struct uci_package *p = NULL;
 594         struct uci_element *e;
 595         bool autoload = false;
 596
 597         p = find_package(L, ctx, package, false);
 598         if (!p) {
 599                 autoload = true;
 600                 p = find_package(L, ctx, package, true);
 601                 if (!p)
 602                         return;
 603         }
 604
 605         if (uci_list_empty(&p->history) && uci_list_empty(&p->saved_history))
 606                 goto done;
 607
 608         lua_newtable(L);
 609         uci_foreach_element(&p->saved_history, e) {
 610                 uci_lua_add_change(L, e);
 611         }
 612         uci_foreach_element(&p->history, e) {
 613                 uci_lua_add_change(L, e);
 614         }
 615         lua_setfield(L, -2, p->e.name);
 616
 617 done:
 618         if (autoload)
 619                 uci_unload(ctx, p);
 620 }
 621
 622 static int
 623 uci_lua_changes(lua_State *L)
 624 {
 625         struct uci_context *ctx;
 626         const char *package = NULL;
 627         char **config = NULL;
 628         int nargs;
 629         int i, offset = 0;
 630
 631         ctx = find_context(L, &offset);
 632         nargs = lua_gettop(L);
 633         switch(nargs - offset) {
 634         case 1:
 635                 package = luaL_checkstring(L, 1 + offset);
 636         case 0:
 637                 break;
 638         default:
 639                 luaL_error(L, "invalid argument count");
 640         }
 641
 642         lua_newtable(L);
 643         if (package) {
 644                 uci_lua_changes_pkg(L, ctx, package);
 645         } else {
 646                 if (uci_list_configs(ctx, &config) != 0)
 647                         goto done;
 648
 649                 for(i = 0; config[i] != NULL; i++) {
 650                         uci_lua_changes_pkg(L, ctx, config[i]);
 651                 }
 652         }
 653
 654 done:
 655         return 1;
 656 }
 657
 658 static int
 659 uci_lua_get_confdir(lua_State *L)
 660 {
 661         struct uci_context *ctx = find_context(L, NULL);
 662         lua_pushstring(L, ctx->confdir);
 663         return 1;
 664 }
 665
 666 static int
 667 uci_lua_set_confdir(lua_State *L)
 668 {
 669         struct uci_context *ctx;
 670         int ret, offset = 0;
 671
 672         ctx = find_context(L, &offset);
 673         luaL_checkstring(L, 1 + offset);
 674         ret = uci_set_confdir(ctx, lua_tostring(L, -1));
 675         return uci_push_status(L, ctx, false);
 676 }
 677
 678 static int
 679 uci_lua_get_savedir(lua_State *L)
 680 {
 681         struct uci_context *ctx = find_context(L, NULL);
 682         lua_pushstring(L, ctx->savedir);
 683         return 1;
 684 }
 685
 686 static int
 687 uci_lua_set_savedir(lua_State *L)
 688 {
 689         struct uci_context *ctx;
 690         int ret, offset = 0;
 691
 692         ctx = find_context(L, &offset);
 693         luaL_checkstring(L, 1 + offset);
 694         ret = uci_set_savedir(ctx, lua_tostring(L, -1));
 695         return uci_push_status(L, ctx, false);
 696 }
 697
 698 static int
 699 uci_lua_gc(lua_State *L)
 700 {
 701         struct uci_context *ctx = find_context(L, NULL);
 702         uci_free_context(ctx);
 703         return 0;
 704 }
 705
 706 static int
 707 uci_lua_cursor(lua_State *L)
 708 {
 709         struct uci_context **u;
 710         int argc = lua_gettop(L);
 711
 712         u = lua_newuserdata(L, sizeof(struct uci_context *));
 713         luaL_getmetatable(L, METANAME);
 714         lua_setmetatable(L, -2);
 715
 716         *u = uci_alloc_context();
 717         if (!*u)
 718                 luaL_error(L, "Cannot allocate UCI context");
 719         switch (argc) {
 720                 case 2:
 721                         if (lua_isstring(L, 2) &&
 722                                 (uci_set_savedir(*u, luaL_checkstring(L, 2)) != UCI_OK))
 723                                 luaL_error(L, "Unable to set savedir");
 724                         /* fall through */
 725                 case 1:
 726                         if (lua_isstring(L, 1) &&
 727                                 (uci_set_confdir(*u, luaL_checkstring(L, 1)) != UCI_OK))
 728                                 luaL_error(L, "Unable to set savedir");
 729                         break;
 730                 default:
 731                         break;
 732         }
 733         return 1;
 734 }
 735
 736 static const luaL_Reg uci[] = {
 737         { "__gc", uci_lua_gc },
 738         { "cursor", uci_lua_cursor },
 739         { "load", uci_lua_load },
 740         { "unload", uci_lua_unload },
 741         { "get", uci_lua_get },
 742         { "get_all", uci_lua_get_all },
 743         { "add", uci_lua_add },
 744         { "set", uci_lua_set },
 745         { "save", uci_lua_save },
 746         { "delete", uci_lua_delete },
 747         { "commit", uci_lua_commit },
 748         { "revert", uci_lua_revert },
 749         { "changes", uci_lua_changes },
 750         { "foreach", uci_lua_foreach },
 751         { "get_confdir", uci_lua_get_confdir },
 752         { "set_confdir", uci_lua_set_confdir },
 753         { "get_savedir", uci_lua_get_savedir },
 754         { "set_savedir", uci_lua_set_savedir },
 755         { NULL, NULL },
 756 };
 757
 758
 759 int
 760 luaopen_uci(lua_State *L)
 761 {
 762         /* create metatable */
 763         luaL_newmetatable(L, METANAME);
 764
 765         /* metatable.__index = metatable */
 766         lua_pushvalue(L, -1);
 767         lua_setfield(L, -2, "__index");
 768
 769         /* fill metatable */
 770         luaL_register(L, NULL, uci);
 771         lua_pop(L, 1);
 772
 773         /* create module */
 774         luaL_register(L, MODNAME, uci);
 775
 776         return 0;
 777 }