lib/yang.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (C) 2018  NetDEF, Inc.
   4  *                     Renato Westphal
   5  */
   6
   7 #include <zebra.h>
   8
   9 #include "log.h"
  10 #include "lib_errors.h"
  11 #include "yang.h"
  12 #include "yang_translator.h"
  13 #include "northbound.h"
  14
  15 DEFINE_MTYPE_STATIC(LIB, YANG_MODULE, "YANG module");
  16 DEFINE_MTYPE_STATIC(LIB, YANG_DATA, "YANG data structure");
  17
  18 /* libyang container. */
  19 struct ly_ctx *ly_native_ctx;
  20
  21 static struct yang_module_embed *embeds, **embedupd = &embeds;
  22
  23 void yang_module_embed(struct yang_module_embed *embed)
  24 {
  25         embed->next = NULL;
  26         *embedupd = embed;
  27         embedupd = &embed->next;
  28 }
  29
  30 static LY_ERR yang_module_imp_clb(const char *mod_name, const char *mod_rev,
  31                                   const char *submod_name,
  32                                   const char *submod_rev, void *user_data,
  33                                   LYS_INFORMAT *format,
  34                                   const char **module_data,
  35                                   void (**free_module_data)(void *, void *))
  36 {
  37         struct yang_module_embed *e;
  38
  39         if (!strcmp(mod_name, "ietf-inet-types") ||
  40             !strcmp(mod_name, "ietf-yang-types"))
  41                 /* libyang has these built in, don't try finding them here */
  42                 return LY_ENOTFOUND;
  43
  44         for (e = embeds; e; e = e->next) {
  45                 if (e->sub_mod_name && submod_name) {
  46                         if (strcmp(e->sub_mod_name, submod_name))
  47                                 continue;
  48
  49                         if (submod_rev && strcmp(e->sub_mod_rev, submod_rev))
  50                                 continue;
  51                 } else {
  52                         if (strcmp(e->mod_name, mod_name))
  53                                 continue;
  54
  55                         if (mod_rev && strcmp(e->mod_rev, mod_rev))
  56                                 continue;
  57                 }
  58
  59                 *format = e->format;
  60                 *module_data = e->data;
  61                 return LY_SUCCESS;
  62         }
  63
  64         /* We get here for indirect modules like ietf-inet-types */
  65         zlog_debug(
  66                 "YANG model \"%s@%s\" \"%s@%s\"not embedded, trying external file",
  67                 mod_name, mod_rev ? mod_rev : "*",
  68                 submod_name ? submod_name : "*", submod_rev ? submod_rev : "*");
  69
  70         return LY_ENOTFOUND;
  71 }
  72
  73 /* clang-format off */
  74 static const char *const frr_native_modules[] = {
  75         "frr-interface",
  76         "frr-vrf",
  77         "frr-routing",
  78         "frr-affinity-map",
  79         "frr-route-map",
  80         "frr-nexthop",
  81         "frr-ripd",
  82         "frr-ripngd",
  83         "frr-isisd",
  84         "frr-vrrpd",
  85         "frr-zebra",
  86         "frr-pathd",
  87 };
  88 /* clang-format on */
  89
  90 /* Generate the yang_modules tree. */
  91 static inline int yang_module_compare(const struct yang_module *a,
  92                                       const struct yang_module *b)
  93 {
  94         return strcmp(a->name, b->name);
  95 }
  96 RB_GENERATE(yang_modules, yang_module, entry, yang_module_compare)
  97
  98 struct yang_modules yang_modules = RB_INITIALIZER(&yang_modules);
  99
 100 struct yang_module *yang_module_load(const char *module_name)
 101 {
 102         struct yang_module *module;
 103         const struct lys_module *module_info;
 104
 105         module_info =
 106                 ly_ctx_load_module(ly_native_ctx, module_name, NULL, NULL);
 107         if (!module_info) {
 108                 flog_err(EC_LIB_YANG_MODULE_LOAD,
 109                          "%s: failed to load data model: %s", __func__,
 110                          module_name);
 111                 exit(1);
 112         }
 113
 114         module = XCALLOC(MTYPE_YANG_MODULE, sizeof(*module));
 115         module->name = module_name;
 116         module->info = module_info;
 117
 118         if (RB_INSERT(yang_modules, &yang_modules, module) != NULL) {
 119                 flog_err(EC_LIB_YANG_MODULE_LOADED_ALREADY,
 120                          "%s: YANG module is loaded already: %s", __func__,
 121                          module_name);
 122                 exit(1);
 123         }
 124
 125         return module;
 126 }
 127
 128 void yang_module_load_all(void)
 129 {
 130         for (size_t i = 0; i < array_size(frr_native_modules); i++)
 131                 yang_module_load(frr_native_modules[i]);
 132 }
 133
 134 struct yang_module *yang_module_find(const char *module_name)
 135 {
 136         struct yang_module s;
 137
 138         s.name = module_name;
 139         return RB_FIND(yang_modules, &yang_modules, &s);
 140 }
 141
 142 int yang_snodes_iterate_subtree(const struct lysc_node *snode,
 143                                 const struct lys_module *module,
 144                                 yang_iterate_cb cb, uint16_t flags, void *arg)
 145 {
 146         const struct lysc_node *child;
 147         int ret = YANG_ITER_CONTINUE;
 148
 149         if (module && snode->module != module)
 150                 goto next;
 151
 152         switch (snode->nodetype) {
 153         case LYS_CONTAINER:
 154                 if (CHECK_FLAG(flags, YANG_ITER_FILTER_NPCONTAINERS)) {
 155                         if (!CHECK_FLAG(snode->flags, LYS_PRESENCE))
 156                                 goto next;
 157                 }
 158                 break;
 159         case LYS_LEAF:
 160                 if (CHECK_FLAG(flags, YANG_ITER_FILTER_LIST_KEYS)) {
 161                         /* Ignore list keys. */
 162                         if (lysc_is_key(snode))
 163                                 goto next;
 164                 }
 165                 break;
 166         case LYS_INPUT:
 167         case LYS_OUTPUT:
 168                 if (CHECK_FLAG(flags, YANG_ITER_FILTER_INPUT_OUTPUT))
 169                         goto next;
 170                 break;
 171         default:
 172                 assert(snode->nodetype != LYS_AUGMENT
 173                        && snode->nodetype != LYS_GROUPING
 174                        && snode->nodetype != LYS_USES);
 175                 break;
 176         }
 177
 178         ret = (*cb)(snode, arg);
 179         if (ret == YANG_ITER_STOP)
 180                 return ret;
 181
 182 next:
 183         /*
 184          * YANG leafs and leaf-lists can't have child nodes.
 185          */
 186         if (CHECK_FLAG(snode->nodetype, LYS_LEAF | LYS_LEAFLIST))
 187                 return YANG_ITER_CONTINUE;
 188
 189         LY_LIST_FOR (lysc_node_child(snode), child) {
 190                 ret = yang_snodes_iterate_subtree(child, module, cb, flags,
 191                                                   arg);
 192                 if (ret == YANG_ITER_STOP)
 193                         return ret;
 194         }
 195         return ret;
 196 }
 197
 198 int yang_snodes_iterate(const struct lys_module *module, yang_iterate_cb cb,
 199                         uint16_t flags, void *arg)
 200 {
 201         const struct lys_module *module_iter;
 202         uint32_t idx = 0;
 203         int ret = YANG_ITER_CONTINUE;
 204
 205         idx = ly_ctx_internal_modules_count(ly_native_ctx);
 206         while ((module_iter = ly_ctx_get_module_iter(ly_native_ctx, &idx))) {
 207                 struct lysc_node *snode;
 208
 209                 if (!module_iter->implemented)
 210                         continue;
 211
 212                 LY_LIST_FOR (module_iter->compiled->data, snode) {
 213                         ret = yang_snodes_iterate_subtree(snode, module, cb,
 214                                                           flags, arg);
 215                         if (ret == YANG_ITER_STOP)
 216                                 return ret;
 217                 }
 218                 LY_LIST_FOR (&module_iter->compiled->rpcs->node, snode) {
 219                         ret = yang_snodes_iterate_subtree(snode, module, cb,
 220                                                           flags, arg);
 221                         if (ret == YANG_ITER_STOP)
 222                                 return ret;
 223                 }
 224                 LY_LIST_FOR (&module_iter->compiled->notifs->node, snode) {
 225                         ret = yang_snodes_iterate_subtree(snode, module, cb,
 226                                                           flags, arg);
 227                         if (ret == YANG_ITER_STOP)
 228                                 return ret;
 229                 }
 230         }
 231
 232         return ret;
 233 }
 234
 235 void yang_snode_get_path(const struct lysc_node *snode,
 236                          enum yang_path_type type, char *xpath,
 237                          size_t xpath_len)
 238 {
 239         switch (type) {
 240         case YANG_PATH_SCHEMA:
 241                 (void)lysc_path(snode, LYSC_PATH_LOG, xpath, xpath_len);
 242                 break;
 243         case YANG_PATH_DATA:
 244                 (void)lysc_path(snode, LYSC_PATH_DATA, xpath, xpath_len);
 245                 break;
 246         default:
 247                 flog_err(EC_LIB_DEVELOPMENT, "%s: unknown yang path type: %u",
 248                          __func__, type);
 249                 exit(1);
 250         }
 251 }
 252
 253 struct lysc_node *yang_snode_real_parent(const struct lysc_node *snode)
 254 {
 255         struct lysc_node *parent = snode->parent;
 256
 257         while (parent) {
 258                 switch (parent->nodetype) {
 259                 case LYS_CONTAINER:
 260                         if (CHECK_FLAG(parent->flags, LYS_PRESENCE))
 261                                 return parent;
 262                         break;
 263                 case LYS_LIST:
 264                         return parent;
 265                 default:
 266                         break;
 267                 }
 268                 parent = parent->parent;
 269         }
 270
 271         return NULL;
 272 }
 273
 274 struct lysc_node *yang_snode_parent_list(const struct lysc_node *snode)
 275 {
 276         struct lysc_node *parent = snode->parent;
 277
 278         while (parent) {
 279                 switch (parent->nodetype) {
 280                 case LYS_LIST:
 281                         return parent;
 282                 default:
 283                         break;
 284                 }
 285                 parent = parent->parent;
 286         }
 287
 288         return NULL;
 289 }
 290
 291 bool yang_snode_is_typeless_data(const struct lysc_node *snode)
 292 {
 293         const struct lysc_node_leaf *sleaf;
 294
 295         switch (snode->nodetype) {
 296         case LYS_LEAF:
 297                 sleaf = (struct lysc_node_leaf *)snode;
 298                 if (sleaf->type->basetype == LY_TYPE_EMPTY)
 299                         return true;
 300                 return false;
 301         case LYS_LEAFLIST:
 302                 return false;
 303         default:
 304                 return true;
 305         }
 306 }
 307
 308 const char *yang_snode_get_default(const struct lysc_node *snode)
 309 {
 310         const struct lysc_node_leaf *sleaf;
 311
 312         switch (snode->nodetype) {
 313         case LYS_LEAF:
 314                 sleaf = (const struct lysc_node_leaf *)snode;
 315                 return sleaf->dflt ? lyd_value_get_canonical(sleaf->module->ctx,
 316                                                              sleaf->dflt)
 317                                    : NULL;
 318         case LYS_LEAFLIST:
 319                 /* TODO: check leaf-list default values */
 320                 return NULL;
 321         default:
 322                 return NULL;
 323         }
 324 }
 325
 326 const struct lysc_type *yang_snode_get_type(const struct lysc_node *snode)
 327 {
 328         struct lysc_node_leaf *sleaf = (struct lysc_node_leaf *)snode;
 329         struct lysc_type *type;
 330
 331         if (!CHECK_FLAG(sleaf->nodetype, LYS_LEAF | LYS_LEAFLIST))
 332                 return NULL;
 333
 334         type = sleaf->type;
 335         while (type->basetype == LY_TYPE_LEAFREF)
 336                 type = ((struct lysc_type_leafref *)type)->realtype;
 337
 338         return type;
 339 }
 340
 341 unsigned int yang_snode_num_keys(const struct lysc_node *snode)
 342 {
 343         const struct lysc_node_leaf *skey;
 344         uint count = 0;
 345
 346         if (!CHECK_FLAG(snode->nodetype, LYS_LIST))
 347                 return 0;
 348
 349         /* Walk list of children */
 350         LY_FOR_KEYS (snode, skey) {
 351                 count++;
 352         }
 353         return count;
 354 }
 355
 356 void yang_dnode_get_path(const struct lyd_node *dnode, char *xpath,
 357                          size_t xpath_len)
 358 {
 359         lyd_path(dnode, LYD_PATH_STD, xpath, xpath_len);
 360 }
 361
 362 const char *yang_dnode_get_schema_name(const struct lyd_node *dnode,
 363                                        const char *xpath_fmt, ...)
 364 {
 365         if (xpath_fmt) {
 366                 va_list ap;
 367                 char xpath[XPATH_MAXLEN];
 368
 369                 va_start(ap, xpath_fmt);
 370                 vsnprintf(xpath, sizeof(xpath), xpath_fmt, ap);
 371                 va_end(ap);
 372
 373                 dnode = yang_dnode_get(dnode, xpath);
 374                 if (!dnode) {
 375                         flog_err(EC_LIB_YANG_DNODE_NOT_FOUND,
 376                                  "%s: couldn't find %s", __func__, xpath);
 377                         zlog_backtrace(LOG_ERR);
 378                         abort();
 379                 }
 380         }
 381
 382         return dnode->schema->name;
 383 }
 384
 385 struct lyd_node *yang_dnode_get(const struct lyd_node *dnode, const char *xpath)
 386 {
 387         struct ly_set *set = NULL;
 388         struct lyd_node *dnode_ret = NULL;
 389
 390         /*
 391          * XXX a lot of the code uses this for style I guess. It shouldn't, as
 392          * it adds to the xpath parsing complexity in libyang.
 393          */
 394         if (xpath[0] == '.' && xpath[1] == '/')
 395                 xpath += 2;
 396
 397         if (lyd_find_xpath(dnode, xpath, &set)) {
 398                 /*
 399                  * Commenting out the below assert failure as it crashes mgmtd
 400                  * when bad xpath is passed.
 401                  *
 402                  * assert(0);  XXX replicates old libyang1 base code
 403                  */
 404                 goto exit;
 405         }
 406         if (set->count == 0)
 407                 goto exit;
 408
 409         if (set->count > 1) {
 410                 flog_warn(EC_LIB_YANG_DNODE_NOT_FOUND,
 411                           "%s: found %u elements (expected 0 or 1) [xpath %s]",
 412                           __func__, set->count, xpath);
 413                 goto exit;
 414         }
 415
 416         dnode_ret = set->dnodes[0];
 417
 418 exit:
 419         ly_set_free(set, NULL);
 420
 421         return dnode_ret;
 422 }
 423
 424 struct lyd_node *yang_dnode_getf(const struct lyd_node *dnode,
 425                                  const char *xpath_fmt, ...)
 426 {
 427         va_list ap;
 428         char xpath[XPATH_MAXLEN];
 429
 430         va_start(ap, xpath_fmt);
 431         vsnprintf(xpath, sizeof(xpath), xpath_fmt, ap);
 432         va_end(ap);
 433
 434         return yang_dnode_get(dnode, xpath);
 435 }
 436
 437 bool yang_dnode_exists(const struct lyd_node *dnode, const char *xpath)
 438 {
 439         struct ly_set *set = NULL;
 440         bool exists = false;
 441
 442         if (xpath[0] == '.' && xpath[1] == '/')
 443                 xpath += 2;
 444         if (lyd_find_xpath(dnode, xpath, &set))
 445                 return false;
 446         exists = set->count > 0;
 447         ly_set_free(set, NULL);
 448         return exists;
 449 }
 450
 451 bool yang_dnode_existsf(const struct lyd_node *dnode, const char *xpath_fmt,
 452                         ...)
 453 {
 454         va_list ap;
 455         char xpath[XPATH_MAXLEN];
 456
 457         va_start(ap, xpath_fmt);
 458         vsnprintf(xpath, sizeof(xpath), xpath_fmt, ap);
 459         va_end(ap);
 460
 461         return yang_dnode_exists(dnode, xpath);
 462 }
 463
 464 void yang_dnode_iterate(yang_dnode_iter_cb cb, void *arg,
 465                         const struct lyd_node *dnode, const char *xpath_fmt,
 466                         ...)
 467 {
 468         va_list ap;
 469         char xpath[XPATH_MAXLEN];
 470         struct ly_set *set;
 471
 472         va_start(ap, xpath_fmt);
 473         vsnprintf(xpath, sizeof(xpath), xpath_fmt, ap);
 474         va_end(ap);
 475
 476         if (lyd_find_xpath(dnode, xpath, &set)) {
 477                 assert(0); /* XXX libyang2: ly1 code asserted success */
 478                 return;
 479         }
 480         for (unsigned int i = 0; i < set->count; i++) {
 481                 int ret;
 482
 483                 ret = (*cb)(set->dnodes[i], arg);
 484                 if (ret == YANG_ITER_STOP)
 485                         break;
 486         }
 487
 488         ly_set_free(set, NULL);
 489 }
 490
 491 bool yang_dnode_is_default(const struct lyd_node *dnode, const char *xpath)
 492 {
 493         const struct lysc_node *snode;
 494         struct lysc_node_leaf *sleaf;
 495
 496         if (xpath)
 497                 dnode = yang_dnode_get(dnode, xpath);
 498
 499         assert(dnode);
 500         snode = dnode->schema;
 501         switch (snode->nodetype) {
 502         case LYS_LEAF:
 503                 sleaf = (struct lysc_node_leaf *)snode;
 504                 if (sleaf->type->basetype == LY_TYPE_EMPTY)
 505                         return false;
 506                 return lyd_is_default(dnode);
 507         case LYS_LEAFLIST:
 508                 /* TODO: check leaf-list default values */
 509                 return false;
 510         case LYS_CONTAINER:
 511                 if (CHECK_FLAG(snode->flags, LYS_PRESENCE))
 512                         return false;
 513                 return true;
 514         default:
 515                 return false;
 516         }
 517 }
 518
 519 bool yang_dnode_is_defaultf(const struct lyd_node *dnode, const char *xpath_fmt,
 520                             ...)
 521 {
 522         if (!xpath_fmt)
 523                 return yang_dnode_is_default(dnode, NULL);
 524         else {
 525                 va_list ap;
 526                 char xpath[XPATH_MAXLEN];
 527
 528                 va_start(ap, xpath_fmt);
 529                 vsnprintf(xpath, sizeof(xpath), xpath_fmt, ap);
 530                 va_end(ap);
 531
 532                 return yang_dnode_is_default(dnode, xpath);
 533         }
 534 }
 535
 536 bool yang_dnode_is_default_recursive(const struct lyd_node *dnode)
 537 {
 538         struct lyd_node *root, *dnode_iter;
 539
 540         if (!yang_dnode_is_default(dnode, NULL))
 541                 return false;
 542
 543         if (CHECK_FLAG(dnode->schema->nodetype, LYS_LEAF | LYS_LEAFLIST))
 544                 return true;
 545
 546         LY_LIST_FOR (lyd_child(dnode), root) {
 547                 LYD_TREE_DFS_BEGIN (root, dnode_iter) {
 548                         if (!yang_dnode_is_default(dnode_iter, NULL))
 549                                 return false;
 550
 551                         LYD_TREE_DFS_END(root, dnode_iter);
 552                 }
 553         }
 554
 555         return true;
 556 }
 557
 558 void yang_dnode_change_leaf(struct lyd_node *dnode, const char *value)
 559 {
 560         assert(dnode->schema->nodetype == LYS_LEAF);
 561         lyd_change_term(dnode, value);
 562 }
 563
 564 struct lyd_node *yang_dnode_new(struct ly_ctx *ly_ctx, bool config_only)
 565 {
 566         struct lyd_node *dnode = NULL;
 567         int options = config_only ? LYD_VALIDATE_NO_STATE : 0;
 568
 569         if (lyd_validate_all(&dnode, ly_ctx, options, NULL) != 0) {
 570                 /* Should never happen. */
 571                 flog_err(EC_LIB_LIBYANG, "%s: lyd_validate() failed", __func__);
 572                 exit(1);
 573         }
 574
 575         return dnode;
 576 }
 577
 578 struct lyd_node *yang_dnode_dup(const struct lyd_node *dnode)
 579 {
 580         struct lyd_node *dup = NULL;
 581         LY_ERR err;
 582         err = lyd_dup_siblings(dnode, NULL, LYD_DUP_RECURSIVE, &dup);
 583         assert(!err);
 584         return dup;
 585 }
 586
 587 void yang_dnode_free(struct lyd_node *dnode)
 588 {
 589         while (dnode->parent)
 590                 dnode = lyd_parent(dnode);
 591         lyd_free_all(dnode);
 592 }
 593
 594 struct yang_data *yang_data_new(const char *xpath, const char *value)
 595 {
 596         struct yang_data *data;
 597
 598         data = XCALLOC(MTYPE_YANG_DATA, sizeof(*data));
 599         strlcpy(data->xpath, xpath, sizeof(data->xpath));
 600         if (value)
 601                 data->value = strdup(value);
 602
 603         return data;
 604 }
 605
 606 void yang_data_free(struct yang_data *data)
 607 {
 608         if (data->value)
 609                 free(data->value);
 610         XFREE(MTYPE_YANG_DATA, data);
 611 }
 612
 613 struct list *yang_data_list_new(void)
 614 {
 615         struct list *list;
 616
 617         list = list_new();
 618         list->del = (void (*)(void *))yang_data_free;
 619
 620         return list;
 621 }
 622
 623 struct yang_data *yang_data_list_find(const struct list *list,
 624                                       const char *xpath_fmt, ...)
 625 {
 626         char xpath[XPATH_MAXLEN];
 627         struct yang_data *data;
 628         struct listnode *node;
 629         va_list ap;
 630
 631         va_start(ap, xpath_fmt);
 632         vsnprintf(xpath, sizeof(xpath), xpath_fmt, ap);
 633         va_end(ap);
 634
 635         for (ALL_LIST_ELEMENTS_RO(list, node, data))
 636                 if (strmatch(data->xpath, xpath))
 637                         return data;
 638
 639         return NULL;
 640 }
 641
 642 /* Make libyang log its errors using FRR logging infrastructure. */
 643 static void ly_log_cb(LY_LOG_LEVEL level, const char *msg, const char *path)
 644 {
 645         int priority = LOG_ERR;
 646
 647         switch (level) {
 648         case LY_LLERR:
 649                 priority = LOG_ERR;
 650                 break;
 651         case LY_LLWRN:
 652                 priority = LOG_WARNING;
 653                 break;
 654         case LY_LLVRB:
 655         case LY_LLDBG:
 656                 priority = LOG_DEBUG;
 657                 break;
 658         }
 659
 660         if (path)
 661                 zlog(priority, "libyang: %s (%s)", msg, path);
 662         else
 663                 zlog(priority, "libyang: %s", msg);
 664 }
 665
 666 const char *yang_print_errors(struct ly_ctx *ly_ctx, char *buf, size_t buf_len)
 667 {
 668         struct ly_err_item *ei;
 669         const char *path;
 670
 671         ei = ly_err_first(ly_ctx);
 672         if (!ei)
 673                 return "";
 674
 675         strlcpy(buf, "YANG error(s):\n", buf_len);
 676         for (; ei; ei = ei->next) {
 677                 strlcat(buf, " ", buf_len);
 678                 strlcat(buf, ei->msg, buf_len);
 679                 strlcat(buf, "\n", buf_len);
 680         }
 681
 682         path = ly_errpath(ly_ctx);
 683         if (path) {
 684                 strlcat(buf, " YANG path: ", buf_len);
 685                 strlcat(buf, path, buf_len);
 686                 strlcat(buf, "\n", buf_len);
 687         }
 688
 689         ly_err_clean(ly_ctx, NULL);
 690
 691         return buf;
 692 }
 693
 694 void yang_debugging_set(bool enable)
 695 {
 696         if (enable) {
 697                 ly_log_level(LY_LLDBG);
 698                 ly_log_dbg_groups(0xFF);
 699         } else {
 700                 ly_log_level(LY_LLERR);
 701                 ly_log_dbg_groups(0);
 702         }
 703 }
 704
 705 struct ly_ctx *yang_ctx_new_setup(bool embedded_modules, bool explicit_compile)
 706 {
 707         struct ly_ctx *ctx = NULL;
 708         const char *yang_models_path = YANG_MODELS_PATH;
 709         LY_ERR err;
 710
 711         if (access(yang_models_path, R_OK | X_OK)) {
 712                 yang_models_path = NULL;
 713                 if (errno == ENOENT)
 714                         zlog_info("yang model directory \"%s\" does not exist",
 715                                   YANG_MODELS_PATH);
 716                 else
 717                         flog_err_sys(EC_LIB_LIBYANG,
 718                                      "cannot access yang model directory \"%s\"",
 719                                      YANG_MODELS_PATH);
 720         }
 721
 722         uint options = LY_CTX_NO_YANGLIBRARY | LY_CTX_DISABLE_SEARCHDIR_CWD;
 723         if (explicit_compile)
 724                 options |= LY_CTX_EXPLICIT_COMPILE;
 725         err = ly_ctx_new(yang_models_path, options, &ctx);
 726         if (err)
 727                 return NULL;
 728
 729         if (embedded_modules)
 730                 ly_ctx_set_module_imp_clb(ctx, yang_module_imp_clb, NULL);
 731
 732         return ctx;
 733 }
 734
 735 void yang_init(bool embedded_modules, bool defer_compile)
 736 {
 737         /* Initialize libyang global parameters that affect all containers. */
 738         ly_set_log_clb(ly_log_cb, 1);
 739         ly_log_options(LY_LOLOG | LY_LOSTORE);
 740
 741         /* Initialize libyang container for native models. */
 742         ly_native_ctx = yang_ctx_new_setup(embedded_modules, defer_compile);
 743         if (!ly_native_ctx) {
 744                 flog_err(EC_LIB_LIBYANG, "%s: ly_ctx_new() failed", __func__);
 745                 exit(1);
 746         }
 747
 748         yang_translator_init();
 749 }
 750
 751 void yang_init_loading_complete(void)
 752 {
 753         /* Compile everything */
 754         if (ly_ctx_compile(ly_native_ctx) != LY_SUCCESS) {
 755                 flog_err(EC_LIB_YANG_MODULE_LOAD,
 756                          "%s: failed to compile loaded modules: %s", __func__,
 757                          ly_errmsg(ly_native_ctx));
 758                 exit(1);
 759         }
 760 }
 761
 762 void yang_terminate(void)
 763 {
 764         struct yang_module *module;
 765
 766         yang_translator_terminate();
 767
 768         while (!RB_EMPTY(yang_modules, &yang_modules)) {
 769                 module = RB_ROOT(yang_modules, &yang_modules);
 770
 771                 /*
 772                  * We shouldn't call ly_ctx_remove_module() here because this
 773                  * function also removes other modules that depend on it.
 774                  *
 775                  * ly_ctx_destroy() will release all memory for us.
 776                  */
 777                 RB_REMOVE(yang_modules, &yang_modules, module);
 778                 XFREE(MTYPE_YANG_MODULE, module);
 779         }
 780
 781         ly_ctx_destroy(ly_native_ctx);
 782 }
 783
 784 const struct lyd_node *yang_dnode_get_parent(const struct lyd_node *dnode,
 785                                              const char *name)
 786 {
 787         const struct lyd_node *orig_dnode = dnode;
 788
 789         while (orig_dnode) {
 790                 switch (orig_dnode->schema->nodetype) {
 791                 case LYS_LIST:
 792                 case LYS_CONTAINER:
 793                         if (!strcmp(orig_dnode->schema->name, name))
 794                                 return orig_dnode;
 795                         break;
 796                 default:
 797                         break;
 798                 }
 799
 800                 orig_dnode = lyd_parent(orig_dnode);
 801         }
 802
 803         return NULL;
 804 }
 805
 806 bool yang_is_last_list_dnode(const struct lyd_node *dnode)
 807 {
 808         return (((dnode->next == NULL)
 809              || (dnode->next
 810                  && (strcmp(dnode->next->schema->name, dnode->schema->name)
 811                      != 0)))
 812             && dnode->prev
 813             && ((dnode->prev == dnode)
 814                 || (strcmp(dnode->prev->schema->name, dnode->schema->name)
 815                     != 0)));
 816 }
 817
 818 bool yang_is_last_level_dnode(const struct lyd_node *dnode)
 819 {
 820         const struct lyd_node *parent;
 821         const struct lyd_node *key_leaf;
 822         uint8_t keys_size;
 823
 824         switch (dnode->schema->nodetype) {
 825         case LYS_LIST:
 826                 assert(dnode->parent);
 827                 parent = lyd_parent(dnode);
 828                 uint snode_num_keys = yang_snode_num_keys(parent->schema);
 829                 /* XXX libyang2: q: really don't understand this code. */
 830                 key_leaf = dnode->prev;
 831                 for (keys_size = 1; keys_size < snode_num_keys; keys_size++)
 832                         key_leaf = key_leaf->prev;
 833                 if (key_leaf->prev == dnode)
 834                         return true;
 835                 break;
 836         case LYS_CONTAINER:
 837                 return true;
 838         default:
 839                 break;
 840         }
 841
 842         return false;
 843 }
 844
 845 const struct lyd_node *
 846 yang_get_subtree_with_no_sibling(const struct lyd_node *dnode)
 847 {
 848         bool parent = true;
 849         const struct lyd_node *node;
 850
 851         node = dnode;
 852         if (node->schema->nodetype != LYS_LIST)
 853                 return node;
 854
 855         while (parent) {
 856                 switch (node->schema->nodetype) {
 857                 case LYS_CONTAINER:
 858                         if (!CHECK_FLAG(node->schema->flags, LYS_PRESENCE)) {
 859                                 if (node->parent
 860                                     && (node->parent->schema->module
 861                                         == dnode->schema->module))
 862                                         node = lyd_parent(node);
 863                                 else
 864                                         parent = false;
 865                         } else
 866                                 parent = false;
 867                         break;
 868                 case LYS_LIST:
 869                         if (yang_is_last_list_dnode(node)
 870                             && yang_is_last_level_dnode(node)) {
 871                                 if (node->parent
 872                                     && (node->parent->schema->module
 873                                         == dnode->schema->module))
 874                                         node = lyd_parent(node);
 875                                 else
 876                                         parent = false;
 877                         } else
 878                                 parent = false;
 879                         break;
 880                 default:
 881                         parent = false;
 882                         break;
 883                 }
 884         }
 885         return node;
 886 }
 887
 888 uint32_t yang_get_list_pos(const struct lyd_node *node)
 889 {
 890         return lyd_list_pos(node);
 891 }
 892
 893 uint32_t yang_get_list_elements_count(const struct lyd_node *node)
 894 {
 895         unsigned int count;
 896         const struct lysc_node *schema;
 897
 898         if (!node
 899             || ((node->schema->nodetype != LYS_LIST)
 900                 && (node->schema->nodetype != LYS_LEAFLIST))) {
 901                 return 0;
 902         }
 903
 904         schema = node->schema;
 905         count = 0;
 906         do {
 907                 if (node->schema == schema)
 908                         ++count;
 909                 node = node->next;
 910         } while (node);
 911         return count;
 912 }