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, int index)
 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         if (index >= 0) {
 200                 lua_pushinteger(L, index);
 201                 lua_setfield(L, -2, ".index");
 202         }
 203
 204         uci_foreach_element(&s->options, e) {
 205                 struct uci_option *o = uci_to_option(e);
 206                 uci_push_option(L, o);
 207                 lua_setfield(L, -2, o->e.name);
 208         }
 209 }
 210
 211 static void
 212 uci_push_package(lua_State *L, struct uci_package *p)
 213 {
 214         struct uci_element *e;
 215         int i = 0;
 216
 217         lua_newtable(L);
 218         uci_foreach_element(&p->sections, e) {
 219                 uci_push_section(L, uci_to_section(e), i);
 220                 lua_setfield(L, -2, e->name);
 221                 i++;
 222         }
 223 }
 224
 225 static int
 226 uci_lua_unload(lua_State *L)
 227 {
 228         struct uci_context *ctx;
 229         struct uci_package *p;
 230         const char *s;
 231         int offset = 0;
 232
 233         ctx = find_context(L, &offset);
 234         luaL_checkstring(L, 1 + offset);
 235         s = lua_tostring(L, 1 + offset);
 236         p = find_package(L, ctx, s, false);
 237         if (p) {
 238                 uci_unload(ctx, p);
 239                 return uci_push_status(L, ctx, false);
 240         } else {
 241                 lua_pushboolean(L, 0);
 242         }
 243         return 1;
 244 }
 245
 246 static int
 247 uci_lua_load(lua_State *L)
 248 {
 249         struct uci_context *ctx;
 250         struct uci_package *p = NULL;
 251         const char *s;
 252         int offset = 0;
 253
 254         ctx = find_context(L, &offset);
 255         uci_lua_unload(L);
 256         lua_pop(L, 1); /* bool ret value of unload */
 257         s = lua_tostring(L, -1);
 258
 259         uci_load(ctx, s, &p);
 260         return uci_push_status(L, ctx, false);
 261 }
 262
 263
 264 static int
 265 uci_lua_foreach(lua_State *L)
 266 {
 267         struct uci_context *ctx;
 268         struct uci_package *p;
 269         struct uci_element *e;
 270         const char *package, *type;
 271         bool ret = false;
 272         int offset = 0;
 273         int i = 0;
 274
 275         ctx = find_context(L, &offset);
 276         package = luaL_checkstring(L, 1 + offset);
 277
 278         if (lua_isnil(L, 2))
 279                 type = NULL;
 280         else
 281                 type = luaL_checkstring(L, 2 + offset);
 282
 283         if (!lua_isfunction(L, 3 + offset) || !package)
 284                 luaL_error(L, "Invalid argument");
 285
 286         p = find_package(L, ctx, package, true);
 287         if (!p)
 288                 goto done;
 289
 290         uci_foreach_element(&p->sections, e) {
 291                 struct uci_section *s = uci_to_section(e);
 292
 293                 i++;
 294
 295                 if (type && (strcmp(s->type, type) != 0))
 296                         continue;
 297
 298                 lua_pushvalue(L, 3 + offset); /* iterator function */
 299                 uci_push_section(L, s, i - 1);
 300                 if (lua_pcall(L, 1, 0, 0) == 0)
 301                         ret = true;
 302         }
 303
 304 done:
 305         lua_pushboolean(L, ret);
 306         return 1;
 307 }
 308
 309 static int
 310 uci_lua_get_any(lua_State *L, bool all)
 311 {
 312         struct uci_context *ctx;
 313         struct uci_element *e = NULL;
 314         struct uci_ptr ptr;
 315         int offset = 0;
 316         char *s = NULL;
 317         int err = UCI_ERR_NOTFOUND;
 318
 319         ctx = find_context(L, &offset);
 320
 321         if (lookup_args(L, ctx, offset, &ptr, &s))
 322                 goto error;
 323
 324         uci_lookup_ptr(ctx, &ptr, NULL, false);
 325         if (!all && !ptr.s) {
 326                 err = UCI_ERR_INVAL;
 327                 goto error;
 328         }
 329         if (!(ptr.flags & UCI_LOOKUP_COMPLETE)) {
 330                 err = UCI_ERR_NOTFOUND;
 331                 goto error;
 332         }
 333
 334         err = UCI_OK;
 335         e = ptr.last;
 336         switch(e->type) {
 337                 case UCI_TYPE_PACKAGE:
 338                         uci_push_package(L, ptr.p);
 339                         break;
 340                 case UCI_TYPE_SECTION:
 341                         if (all)
 342                                 uci_push_section(L, ptr.s, -1);
 343                         else
 344                                 lua_pushstring(L, ptr.s->type);
 345                         break;
 346                 case UCI_TYPE_OPTION:
 347                         uci_push_option(L, ptr.o);
 348                         break;
 349                 default:
 350                         err = UCI_ERR_INVAL;
 351                         goto error;
 352         }
 353         if (!err)
 354                 return 1;
 355
 356 error:
 357         if (s)
 358                 free(s);
 359
 360         lua_pushnil(L);
 361         return uci_push_status(L, ctx, true);
 362 }
 363
 364 static int
 365 uci_lua_get(lua_State *L)
 366 {
 367         return uci_lua_get_any(L, false);
 368 }
 369
 370 static int
 371 uci_lua_get_all(lua_State *L)
 372 {
 373         return uci_lua_get_any(L, true);
 374 }
 375
 376 static int
 377 uci_lua_add(lua_State *L)
 378 {
 379         struct uci_context *ctx;
 380         struct uci_section *s = NULL;
 381         struct uci_package *p;
 382         const char *package;
 383         const char *type;
 384         const char *name = NULL;
 385         int offset = 0;
 386
 387         ctx = find_context(L, &offset);
 388         package = luaL_checkstring(L, 1 + offset);
 389         type = luaL_checkstring(L, 2 + offset);
 390         p = find_package(L, ctx, package, true);
 391         if (!p)
 392                 goto fail;
 393
 394         if (uci_add_section(ctx, p, type, &s) || !s)
 395                 goto fail;
 396
 397         name = s->e.name;
 398         lua_pushstring(L, name);
 399         return 1;
 400
 401 fail:
 402         lua_pushnil(L);
 403         return uci_push_status(L, ctx, true);
 404 }
 405
 406 static int
 407 uci_lua_delete(lua_State *L)
 408 {
 409         struct uci_context *ctx;
 410         struct uci_ptr ptr;
 411         int offset = 0;
 412         char *s = NULL;
 413         int err = UCI_ERR_NOTFOUND;
 414
 415         ctx = find_context(L, &offset);
 416
 417         if (lookup_args(L, ctx, offset, &ptr, &s))
 418                 goto error;
 419
 420         err = uci_delete(ctx, &ptr);
 421
 422 error:
 423         if (s)
 424                 free(s);
 425         return uci_push_status(L, ctx, false);
 426 }
 427
 428 static int
 429 uci_lua_set(lua_State *L)
 430 {
 431         struct uci_context *ctx;
 432         struct uci_ptr ptr;
 433         bool istable = false;
 434         int err = UCI_ERR_MEM;
 435         char *s = NULL;
 436         int i, nargs, offset = 0;
 437
 438         ctx = find_context(L, &offset);
 439         nargs = lua_gettop(L);
 440         if (lookup_args(L, ctx, offset, &ptr, &s))
 441                 goto error;
 442
 443         switch(nargs - offset) {
 444         case 1:
 445                 /* Format: uci.set("p.s.o=v") or uci.set("p.s=v") */
 446                 break;
 447         case 4:
 448                 /* Format: uci.set("p", "s", "o", "v") */
 449                 if (lua_istable(L, nargs)) {
 450                         if (lua_objlen(L, nargs) < 1)
 451                                 luaL_error(L, "Cannot set an uci option to an empty table value");
 452                         lua_rawgeti(L, nargs, 1);
 453                         ptr.value = luaL_checkstring(L, -1);
 454                         lua_pop(L, 1);
 455                         istable = true;
 456                 } else {
 457                         ptr.value = luaL_checkstring(L, nargs);
 458                 }
 459                 break;
 460         case 3:
 461                 /* Format: uci.set("p", "s", "v") */
 462                 ptr.value = ptr.option;
 463                 ptr.option = NULL;
 464                 break;
 465         default:
 466                 err = UCI_ERR_INVAL;
 467                 goto error;
 468         }
 469
 470         err = uci_lookup_ptr(ctx, &ptr, NULL, false);
 471         if (err)
 472                 goto error;
 473
 474         if (((ptr.s == NULL) && (ptr.option != NULL)) || (ptr.value == NULL)) {
 475                 err = UCI_ERR_INVAL;
 476                 goto error;
 477         }
 478
 479         if (istable) {
 480                 for (i = 1; i <= lua_objlen(L, nargs); i++) {
 481                         lua_rawgeti(L, nargs, i);
 482                         ptr.value = luaL_checkstring(L, -1);
 483                         err = uci_add_list(ctx, &ptr);
 484                         lua_pop(L, 1);
 485                         if (err)
 486                                 goto error;
 487                 }
 488         } else {
 489                 err = uci_set(ctx, &ptr);
 490                 if (err)
 491                         goto error;
 492         }
 493
 494
 495 error:
 496         return uci_push_status(L, ctx, false);
 497 }
 498
 499 enum pkg_cmd {
 500         CMD_SAVE,
 501         CMD_COMMIT,
 502         CMD_REVERT
 503 };
 504
 505 static int
 506 uci_lua_package_cmd(lua_State *L, enum pkg_cmd cmd)
 507 {
 508         struct uci_context *ctx;
 509         struct uci_element *e, *tmp;
 510         struct uci_ptr ptr;
 511         char *s = NULL;
 512         int failed = 0;
 513         int nargs, offset = 0;
 514
 515         ctx = find_context(L, &offset);
 516         nargs = lua_gettop(L);
 517         if ((cmd != CMD_REVERT) && (nargs - offset > 1))
 518                 goto err;
 519
 520         if (lookup_args(L, ctx, offset, &ptr, &s))
 521                 goto err;
 522
 523         uci_lookup_ptr(ctx, &ptr, NULL, false);
 524
 525         uci_foreach_element_safe(&ctx->root, tmp, e) {
 526                 struct uci_package *p = uci_to_package(e);
 527                 int ret = UCI_ERR_INVAL;
 528
 529                 if (ptr.p && (ptr.p != p))
 530                         continue;
 531
 532                 ptr.p = p;
 533                 switch(cmd) {
 534                 case CMD_COMMIT:
 535                         ret = uci_commit(ctx, &p, false);
 536                         break;
 537                 case CMD_SAVE:
 538                         ret = uci_save(ctx, p);
 539                         break;
 540                 case CMD_REVERT:
 541                         ret = uci_revert(ctx, &ptr);
 542                         break;
 543                 }
 544
 545                 if (ret != 0)
 546                         failed = 1;
 547         }
 548
 549 err:
 550         return uci_push_status(L, ctx, false);
 551 }
 552
 553 static int
 554 uci_lua_save(lua_State *L)
 555 {
 556         return uci_lua_package_cmd(L, CMD_SAVE);
 557 }
 558
 559 static int
 560 uci_lua_commit(lua_State *L)
 561 {
 562         return uci_lua_package_cmd(L, CMD_COMMIT);
 563 }
 564
 565 static int
 566 uci_lua_revert(lua_State *L)
 567 {
 568         return uci_lua_package_cmd(L, CMD_REVERT);
 569 }
 570
 571 static void
 572 uci_lua_add_change(lua_State *L, struct uci_element *e)
 573 {
 574         struct uci_history *h;
 575         const char *name;
 576
 577         h = uci_to_history(e);
 578         if (!h->section)
 579                 return;
 580
 581         lua_getfield(L, -1, h->section);
 582         if (lua_isnil(L, -1)) {
 583                 lua_pop(L, 1);
 584                 lua_newtable(L);
 585                 lua_pushvalue(L, -1); /* copy for setfield */
 586                 lua_setfield(L, -3, h->section);
 587         }
 588
 589         name = (h->e.name ? h->e.name : ".type");
 590         if (h->value)
 591                 lua_pushstring(L, h->value);
 592         else
 593                 lua_pushstring(L, "");
 594         lua_setfield(L, -2, name);
 595         lua_pop(L, 1);
 596 }
 597
 598 static void
 599 uci_lua_changes_pkg(lua_State *L, struct uci_context *ctx, const char *package)
 600 {
 601         struct uci_package *p = NULL;
 602         struct uci_element *e;
 603         bool autoload = false;
 604
 605         p = find_package(L, ctx, package, false);
 606         if (!p) {
 607                 autoload = true;
 608                 p = find_package(L, ctx, package, true);
 609                 if (!p)
 610                         return;
 611         }
 612
 613         if (uci_list_empty(&p->history) && uci_list_empty(&p->saved_history))
 614                 goto done;
 615
 616         lua_newtable(L);
 617         uci_foreach_element(&p->saved_history, e) {
 618                 uci_lua_add_change(L, e);
 619         }
 620         uci_foreach_element(&p->history, e) {
 621                 uci_lua_add_change(L, e);
 622         }
 623         lua_setfield(L, -2, p->e.name);
 624
 625 done:
 626         if (autoload)
 627                 uci_unload(ctx, p);
 628 }
 629
 630 static int
 631 uci_lua_changes(lua_State *L)
 632 {
 633         struct uci_context *ctx;
 634         const char *package = NULL;
 635         char **config = NULL;
 636         int nargs;
 637         int i, offset = 0;
 638
 639         ctx = find_context(L, &offset);
 640         nargs = lua_gettop(L);
 641         switch(nargs - offset) {
 642         case 1:
 643                 package = luaL_checkstring(L, 1 + offset);
 644         case 0:
 645                 break;
 646         default:
 647                 luaL_error(L, "invalid argument count");
 648         }
 649
 650         lua_newtable(L);
 651         if (package) {
 652                 uci_lua_changes_pkg(L, ctx, package);
 653         } else {
 654                 if (uci_list_configs(ctx, &config) != 0)
 655                         goto done;
 656
 657                 for(i = 0; config[i] != NULL; i++) {
 658                         uci_lua_changes_pkg(L, ctx, config[i]);
 659                 }
 660         }
 661
 662 done:
 663         return 1;
 664 }
 665
 666 static int
 667 uci_lua_get_confdir(lua_State *L)
 668 {
 669         struct uci_context *ctx = find_context(L, NULL);
 670         lua_pushstring(L, ctx->confdir);
 671         return 1;
 672 }
 673
 674 static int
 675 uci_lua_set_confdir(lua_State *L)
 676 {
 677         struct uci_context *ctx;
 678         int ret, offset = 0;
 679
 680         ctx = find_context(L, &offset);
 681         luaL_checkstring(L, 1 + offset);
 682         ret = uci_set_confdir(ctx, lua_tostring(L, -1));
 683         return uci_push_status(L, ctx, false);
 684 }
 685
 686 static int
 687 uci_lua_get_savedir(lua_State *L)
 688 {
 689         struct uci_context *ctx = find_context(L, NULL);
 690         lua_pushstring(L, ctx->savedir);
 691         return 1;
 692 }
 693
 694 static int
 695 uci_lua_set_savedir(lua_State *L)
 696 {
 697         struct uci_context *ctx;
 698         int ret, offset = 0;
 699
 700         ctx = find_context(L, &offset);
 701         luaL_checkstring(L, 1 + offset);
 702         ret = uci_set_savedir(ctx, lua_tostring(L, -1));
 703         return uci_push_status(L, ctx, false);
 704 }
 705
 706 static int
 707 uci_lua_gc(lua_State *L)
 708 {
 709         struct uci_context *ctx = find_context(L, NULL);
 710         uci_free_context(ctx);
 711         return 0;
 712 }
 713
 714 static int
 715 uci_lua_cursor(lua_State *L)
 716 {
 717         struct uci_context **u;
 718         int argc = lua_gettop(L);
 719
 720         u = lua_newuserdata(L, sizeof(struct uci_context *));
 721         luaL_getmetatable(L, METANAME);
 722         lua_setmetatable(L, -2);
 723
 724         *u = uci_alloc_context();
 725         if (!*u)
 726                 luaL_error(L, "Cannot allocate UCI context");
 727         switch (argc) {
 728                 case 2:
 729                         if (lua_isstring(L, 2) &&
 730                                 (uci_set_savedir(*u, luaL_checkstring(L, 2)) != UCI_OK))
 731                                 luaL_error(L, "Unable to set savedir");
 732                         /* fall through */
 733                 case 1:
 734                         if (lua_isstring(L, 1) &&
 735                                 (uci_set_confdir(*u, luaL_checkstring(L, 1)) != UCI_OK))
 736                                 luaL_error(L, "Unable to set savedir");
 737                         break;
 738                 default:
 739                         break;
 740         }
 741         return 1;
 742 }
 743
 744 static const luaL_Reg uci[] = {
 745         { "__gc", uci_lua_gc },
 746         { "cursor", uci_lua_cursor },
 747         { "load", uci_lua_load },
 748         { "unload", uci_lua_unload },
 749         { "get", uci_lua_get },
 750         { "get_all", uci_lua_get_all },
 751         { "add", uci_lua_add },
 752         { "set", uci_lua_set },
 753         { "save", uci_lua_save },
 754         { "delete", uci_lua_delete },
 755         { "commit", uci_lua_commit },
 756         { "revert", uci_lua_revert },
 757         { "changes", uci_lua_changes },
 758         { "foreach", uci_lua_foreach },
 759         { "get_confdir", uci_lua_get_confdir },
 760         { "set_confdir", uci_lua_set_confdir },
 761         { "get_savedir", uci_lua_get_savedir },
 762         { "set_savedir", uci_lua_set_savedir },
 763         { NULL, NULL },
 764 };
 765
 766
 767 int
 768 luaopen_uci(lua_State *L)
 769 {
 770         /* create metatable */
 771         luaL_newmetatable(L, METANAME);
 772
 773         /* metatable.__index = metatable */
 774         lua_pushvalue(L, -1);
 775         lua_setfield(L, -2, "__index");
 776
 777         /* fill metatable */
 778         luaL_register(L, NULL, uci);
 779         lua_pop(L, 1);
 780
 781         /* create module */
 782         luaL_register(L, MODNAME, uci);
 783
 784         return 0;
 785 }