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 error:
 347         if (s)
 348                 free(s);
 349
 350         lua_pushnil(L);
 351         return uci_push_status(L, ctx, true);
 352 }
 353
 354 static int
 355 uci_lua_get(lua_State *L)
 356 {
 357         return uci_lua_get_any(L, false);
 358 }
 359
 360 static int
 361 uci_lua_get_all(lua_State *L)
 362 {
 363         return uci_lua_get_any(L, true);
 364 }
 365
 366 static int
 367 uci_lua_add(lua_State *L)
 368 {
 369         struct uci_context *ctx;
 370         struct uci_section *s = NULL;
 371         struct uci_package *p;
 372         const char *package;
 373         const char *type;
 374         const char *name = NULL;
 375         int offset = 0;
 376
 377         ctx = find_context(L, &offset);
 378         package = luaL_checkstring(L, 1 + offset);
 379         type = luaL_checkstring(L, 2 + offset);
 380         p = find_package(L, ctx, package, true);
 381         if (!p)
 382                 goto fail;
 383
 384         if (uci_add_section(ctx, p, type, &s) || !s)
 385                 goto fail;
 386
 387         name = s->e.name;
 388         lua_pushstring(L, name);
 389         return 1;
 390
 391 fail:
 392         lua_pushnil(L);
 393         return uci_push_status(L, ctx, true);
 394 }
 395
 396 static int
 397 uci_lua_delete(lua_State *L)
 398 {
 399         struct uci_context *ctx;
 400         struct uci_ptr ptr;
 401         int offset = 0;
 402         char *s = NULL;
 403         int err = UCI_ERR_NOTFOUND;
 404
 405         ctx = find_context(L, &offset);
 406
 407         if (lookup_args(L, ctx, offset, &ptr, &s))
 408                 goto error;
 409
 410         err = uci_delete(ctx, &ptr);
 411
 412 error:
 413         if (s)
 414                 free(s);
 415         return uci_push_status(L, ctx, false);
 416 }
 417
 418 static int
 419 uci_lua_set(lua_State *L)
 420 {
 421         struct uci_context *ctx;
 422         struct uci_ptr ptr;
 423         bool istable = false;
 424         int err = UCI_ERR_MEM;
 425         char *s = NULL;
 426         int i, nargs, offset = 0;
 427
 428         ctx = find_context(L, &offset);
 429         nargs = lua_gettop(L);
 430         if (lookup_args(L, ctx, offset, &ptr, &s))
 431                 goto error;
 432
 433         switch(nargs - offset) {
 434         case 1:
 435                 /* Format: uci.set("p.s.o=v") or uci.set("p.s=v") */
 436                 break;
 437         case 4:
 438                 /* Format: uci.set("p", "s", "o", "v") */
 439                 if (lua_istable(L, nargs)) {
 440                         if (lua_objlen(L, nargs) < 1)
 441                                 luaL_error(L, "Cannot set an uci option to an empty table value");
 442                         lua_rawgeti(L, nargs, 1);
 443                         ptr.value = luaL_checkstring(L, -1);
 444                         lua_pop(L, 1);
 445                         istable = true;
 446                 } else {
 447                         ptr.value = luaL_checkstring(L, nargs);
 448                 }
 449                 break;
 450         case 3:
 451                 /* Format: uci.set("p", "s", "v") */
 452                 ptr.value = ptr.option;
 453                 ptr.option = NULL;
 454                 break;
 455         default:
 456                 err = UCI_ERR_INVAL;
 457                 goto error;
 458         }
 459
 460         err = uci_lookup_ptr(ctx, &ptr, NULL, false);
 461         if (err)
 462                 goto error;
 463
 464         if (((ptr.s == NULL) && (ptr.option != NULL)) || (ptr.value == NULL)) {
 465                 err = UCI_ERR_INVAL;
 466                 goto error;
 467         }
 468
 469         err = uci_set(ctx, &ptr);
 470         if (err)
 471                 goto error;
 472
 473         if (istable) {
 474                 for (i = 2; i <= lua_objlen(L, nargs); i++) {
 475                         lua_rawgeti(L, nargs, i);
 476                         ptr.value = luaL_checkstring(L, -1);
 477                         err = uci_add_list(ctx, &ptr);
 478                         lua_pop(L, 1);
 479                         if (err)
 480                                 goto error;
 481                 }
 482         }
 483
 484 error:
 485         return uci_push_status(L, ctx, false);
 486 }
 487
 488 enum pkg_cmd {
 489         CMD_SAVE,
 490         CMD_COMMIT,
 491         CMD_REVERT
 492 };
 493
 494 static int
 495 uci_lua_package_cmd(lua_State *L, enum pkg_cmd cmd)
 496 {
 497         struct uci_context *ctx;
 498         struct uci_element *e, *tmp;
 499         struct uci_ptr ptr;
 500         char *s = NULL;
 501         int failed = 0;
 502         int nargs, offset = 0;
 503
 504         ctx = find_context(L, &offset);
 505         nargs = lua_gettop(L);
 506         if ((cmd != CMD_REVERT) && (nargs > 1))
 507                 goto err;
 508
 509         if (lookup_args(L, ctx, offset, &ptr, &s))
 510                 goto err;
 511
 512         uci_lookup_ptr(ctx, &ptr, NULL, false);
 513
 514         uci_foreach_element_safe(&ctx->root, tmp, e) {
 515                 struct uci_package *p = uci_to_package(e);
 516                 int ret = UCI_ERR_INVAL;
 517
 518                 if (ptr.p && (ptr.p != p))
 519                         continue;
 520
 521                 ptr.p = p;
 522                 switch(cmd) {
 523                 case CMD_COMMIT:
 524                         ret = uci_commit(ctx, &p, false);
 525                         break;
 526                 case CMD_SAVE:
 527                         ret = uci_save(ctx, p);
 528                         break;
 529                 case CMD_REVERT:
 530                         ret = uci_revert(ctx, &ptr);
 531                         break;
 532                 }
 533
 534                 if (ret != 0)
 535                         failed = 1;
 536         }
 537
 538 err:
 539         return uci_push_status(L, ctx, false);
 540 }
 541
 542 static int
 543 uci_lua_save(lua_State *L)
 544 {
 545         return uci_lua_package_cmd(L, CMD_SAVE);
 546 }
 547
 548 static int
 549 uci_lua_commit(lua_State *L)
 550 {
 551         return uci_lua_package_cmd(L, CMD_COMMIT);
 552 }
 553
 554 static int
 555 uci_lua_revert(lua_State *L)
 556 {
 557         return uci_lua_package_cmd(L, CMD_REVERT);
 558 }
 559
 560 static void
 561 uci_lua_add_change(lua_State *L, struct uci_element *e)
 562 {
 563         struct uci_history *h;
 564         const char *name;
 565
 566         h = uci_to_history(e);
 567         if (!h->section)
 568                 return;
 569
 570         lua_getfield(L, -1, h->section);
 571         if (lua_isnil(L, -1)) {
 572                 lua_pop(L, 1);
 573                 lua_newtable(L);
 574                 lua_pushvalue(L, -1); /* copy for setfield */
 575                 lua_setfield(L, -3, h->section);
 576         }
 577
 578         name = (h->e.name ? h->e.name : ".type");
 579         if (h->value)
 580                 lua_pushstring(L, h->value);
 581         else
 582                 lua_pushstring(L, "");
 583         lua_setfield(L, -2, name);
 584         lua_pop(L, 1);
 585 }
 586
 587 static void
 588 uci_lua_changes_pkg(lua_State *L, struct uci_context *ctx, const char *package)
 589 {
 590         struct uci_package *p = NULL;
 591         struct uci_element *e;
 592         bool autoload = false;
 593
 594         p = find_package(L, ctx, package, false);
 595         if (!p) {
 596                 autoload = true;
 597                 p = find_package(L, ctx, package, true);
 598                 if (!p)
 599                         return;
 600         }
 601
 602         if (uci_list_empty(&p->history) && uci_list_empty(&p->saved_history))
 603                 goto done;
 604
 605         lua_newtable(L);
 606         uci_foreach_element(&p->saved_history, e) {
 607                 uci_lua_add_change(L, e);
 608         }
 609         uci_foreach_element(&p->history, e) {
 610                 uci_lua_add_change(L, e);
 611         }
 612         lua_setfield(L, -2, p->e.name);
 613
 614 done:
 615         if (autoload)
 616                 uci_unload(ctx, p);
 617 }
 618
 619 static int
 620 uci_lua_changes(lua_State *L)
 621 {
 622         struct uci_context *ctx;
 623         const char *package = NULL;
 624         char **config = NULL;
 625         int nargs;
 626         int i, offset = 0;
 627
 628         ctx = find_context(L, &offset);
 629         nargs = lua_gettop(L);
 630         switch(nargs - offset) {
 631         case 1:
 632                 package = luaL_checkstring(L, 1 + offset);
 633         case 0:
 634                 break;
 635         default:
 636                 luaL_error(L, "invalid argument count");
 637         }
 638
 639         lua_newtable(L);
 640         if (package) {
 641                 uci_lua_changes_pkg(L, ctx, package);
 642         } else {
 643                 if (uci_list_configs(ctx, &config) != 0)
 644                         goto done;
 645
 646                 for(i = 0; config[i] != NULL; i++) {
 647                         uci_lua_changes_pkg(L, ctx, config[i]);
 648                 }
 649         }
 650
 651 done:
 652         return 1;
 653 }
 654
 655 static int
 656 uci_lua_get_confdir(lua_State *L)
 657 {
 658         struct uci_context *ctx = find_context(L, NULL);
 659         lua_pushstring(L, ctx->confdir);
 660         return 1;
 661 }
 662
 663 static int
 664 uci_lua_set_confdir(lua_State *L)
 665 {
 666         struct uci_context *ctx;
 667         int ret, offset = 0;
 668
 669         ctx = find_context(L, &offset);
 670         luaL_checkstring(L, 1 + offset);
 671         ret = uci_set_confdir(ctx, lua_tostring(L, -1));
 672         return uci_push_status(L, ctx, false);
 673 }
 674
 675 static int
 676 uci_lua_get_savedir(lua_State *L)
 677 {
 678         struct uci_context *ctx = find_context(L, NULL);
 679         lua_pushstring(L, ctx->savedir);
 680         return 1;
 681 }
 682
 683 static int
 684 uci_lua_set_savedir(lua_State *L)
 685 {
 686         struct uci_context *ctx;
 687         int ret, offset = 0;
 688
 689         ctx = find_context(L, &offset);
 690         luaL_checkstring(L, 1 + offset);
 691         ret = uci_set_savedir(ctx, lua_tostring(L, -1));
 692         return uci_push_status(L, ctx, false);
 693 }
 694
 695 static int
 696 uci_lua_gc(lua_State *L)
 697 {
 698         struct uci_context *ctx = find_context(L, NULL);
 699         uci_free_context(ctx);
 700         return 0;
 701 }
 702
 703 static int
 704 uci_lua_cursor(lua_State *L)
 705 {
 706         struct uci_context **u;
 707         int argc = lua_gettop(L);
 708
 709         u = lua_newuserdata(L, sizeof(struct uci_context *));
 710         luaL_getmetatable(L, METANAME);
 711         lua_setmetatable(L, -2);
 712
 713         *u = uci_alloc_context();
 714         if (!*u)
 715                 luaL_error(L, "Cannot allocate UCI context");
 716         switch (argc) {
 717                 case 2:
 718                         if (lua_isstring(L, 2) &&
 719                                 (uci_set_savedir(*u, luaL_checkstring(L, 2)) != UCI_OK))
 720                                 luaL_error(L, "Unable to set savedir");
 721                         /* fall through */
 722                 case 1:
 723                         if (lua_isstring(L, 1) &&
 724                                 (uci_set_confdir(*u, luaL_checkstring(L, 1)) != UCI_OK))
 725                                 luaL_error(L, "Unable to set savedir");
 726                         break;
 727                 default:
 728                         break;
 729         }
 730         return 1;
 731 }
 732
 733 static const luaL_Reg uci[] = {
 734         { "__gc", uci_lua_gc },
 735         { "cursor", uci_lua_cursor },
 736         { "load", uci_lua_load },
 737         { "unload", uci_lua_unload },
 738         { "get", uci_lua_get },
 739         { "get_all", uci_lua_get_all },
 740         { "add", uci_lua_add },
 741         { "set", uci_lua_set },
 742         { "save", uci_lua_save },
 743         { "delete", uci_lua_delete },
 744         { "commit", uci_lua_commit },
 745         { "revert", uci_lua_revert },
 746         { "changes", uci_lua_changes },
 747         { "foreach", uci_lua_foreach },
 748         { "get_confdir", uci_lua_get_confdir },
 749         { "set_confdir", uci_lua_set_confdir },
 750         { "get_savedir", uci_lua_get_savedir },
 751         { "set_savedir", uci_lua_set_savedir },
 752         { NULL, NULL },
 753 };
 754
 755
 756 int
 757 luaopen_uci(lua_State *L)
 758 {
 759         /* create metatable */
 760         luaL_newmetatable(L, METANAME);
 761
 762         /* metatable.__index = metatable */
 763         lua_pushvalue(L, -1);
 764         lua_setfield(L, -2, "__index");
 765
 766         /* fill metatable */
 767         luaL_register(L, NULL, uci);
 768         lua_pop(L, 1);
 769
 770         /* create module */
 771         luaL_register(L, MODNAME, uci);
 772
 773         return 0;
 774 }