list.c

   1 /*
   2  * libuci - Library for the Unified Configuration Interface
   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 Lesser General Public License version 2.1
   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 /* initialize a list head/item */
  16 static inline void uci_list_init(struct uci_list *ptr)
  17 {
  18         ptr->prev = ptr;
  19         ptr->next = ptr;
  20 }
  21
  22 /* inserts a new list entry after a given entry */
  23 static inline void uci_list_insert(struct uci_list *list, struct uci_list *ptr)
  24 {
  25         list->next->prev = ptr;
  26         ptr->prev = list;
  27         ptr->next = list->next;
  28         list->next = ptr;
  29 }
  30
  31 /* inserts a new list entry at the tail of the list */
  32 static inline void uci_list_add(struct uci_list *head, struct uci_list *ptr)
  33 {
  34         /* NB: head->prev points at the tail */
  35         uci_list_insert(head->prev, ptr);
  36 }
  37
  38 static inline void uci_list_del(struct uci_list *ptr)
  39 {
  40         struct uci_list *next, *prev;
  41
  42         next = ptr->next;
  43         prev = ptr->prev;
  44
  45         prev->next = next;
  46         next->prev = prev;
  47
  48         uci_list_init(ptr);
  49 }
  50
  51 /*
  52  * uci_alloc_generic allocates a new uci_element with payload
  53  * payload is appended to the struct to save memory and reduce fragmentation
  54  */
  55 static struct uci_element *
  56 uci_alloc_generic(struct uci_context *ctx, int type, const char *name, int size)
  57 {
  58         struct uci_element *e;
  59         int datalen = size;
  60         void *ptr;
  61
  62         ptr = uci_malloc(ctx, datalen);
  63         e = (struct uci_element *) ptr;
  64         e->type = type;
  65         if (name) {
  66                 UCI_TRAP_SAVE(ctx, error);
  67                 e->name = uci_strdup(ctx, name);
  68                 UCI_TRAP_RESTORE(ctx);
  69         }
  70         uci_list_init(&e->list);
  71         goto done;
  72
  73 error:
  74         free(ptr);
  75         UCI_THROW(ctx, ctx->err);
  76
  77 done:
  78         return e;
  79 }
  80
  81 static void
  82 uci_free_element(struct uci_element *e)
  83 {
  84         if (e->name)
  85                 free(e->name);
  86         if (!uci_list_empty(&e->list))
  87                 uci_list_del(&e->list);
  88         free(e);
  89 }
  90
  91 static struct uci_option *
  92 uci_alloc_option(struct uci_section *s, const char *name, const char *value)
  93 {
  94         struct uci_package *p = s->package;
  95         struct uci_context *ctx = p->ctx;
  96         struct uci_option *o;
  97
  98         o = uci_alloc_element(ctx, option, name, strlen(value) + 1);
  99         o->type = UCI_TYPE_STRING;
 100         o->v.string = uci_dataptr(o);
 101         o->section = s;
 102         strcpy(o->v.string, value);
 103         uci_list_add(&s->options, &o->e.list);
 104
 105         return o;
 106 }
 107
 108 static inline void
 109 uci_free_option(struct uci_option *o)
 110 {
 111         struct uci_element *e, *tmp;
 112
 113         switch(o->type) {
 114         case UCI_TYPE_STRING:
 115                 if ((o->v.string != uci_dataptr(o)) &&
 116                         (o->v.string != NULL))
 117                         free(o->v.string);
 118                 break;
 119         case UCI_TYPE_LIST:
 120                 uci_foreach_element_safe(&o->v.list, tmp, e) {
 121                         uci_free_element(e);
 122                 }
 123                 break;
 124         default:
 125                 break;
 126         }
 127         uci_free_element(&o->e);
 128 }
 129
 130 static struct uci_option *
 131 uci_alloc_list(struct uci_section *s, const char *name)
 132 {
 133         struct uci_package *p = s->package;
 134         struct uci_context *ctx = p->ctx;
 135         struct uci_option *o;
 136
 137         o = uci_alloc_element(ctx, option, name, 0);
 138         o->type = UCI_TYPE_LIST;
 139         o->section = s;
 140         uci_list_init(&o->v.list);
 141         uci_list_add(&s->options, &o->e.list);
 142
 143         return o;
 144 }
 145
 146 /* fix up an unnamed section, e.g. after adding options to it */
 147 static void uci_fixup_section(struct uci_context *ctx, struct uci_section *s)
 148 {
 149         unsigned int hash = ~0;
 150         struct uci_element *e;
 151         char buf[16];
 152
 153         if (!s || s->e.name)
 154                 return;
 155
 156         /*
 157          * Generate a name for unnamed sections. This is used as reference
 158          * when locating or updating the section from apps/scripts.
 159          * To make multiple concurrent versions somewhat safe for updating,
 160          * the name is generated from a hash of its type and name/value
 161          * pairs of its option, and it is prefixed by a counter value.
 162          * If the order of the unnamed sections changes for some reason,
 163          * updates to them will be rejected.
 164          */
 165         hash = djbhash(hash, s->type);
 166         uci_foreach_element(&s->options, e) {
 167                 struct uci_option *o;
 168                 hash = djbhash(hash, e->name);
 169                 o = uci_to_option(e);
 170                 switch(o->type) {
 171                 case UCI_TYPE_STRING:
 172                         hash = djbhash(hash, o->v.string);
 173                         break;
 174                 default:
 175                         break;
 176                 }
 177         }
 178         sprintf(buf, "cfg%02x%04x", ++s->package->n_section, hash % (1 << 16));
 179         s->e.name = uci_strdup(ctx, buf);
 180 }
 181
 182 static struct uci_section *
 183 uci_alloc_section(struct uci_package *p, const char *type, const char *name)
 184 {
 185         struct uci_context *ctx = p->ctx;
 186         struct uci_section *s;
 187
 188         if (name && !name[0])
 189                 name = NULL;
 190
 191         s = uci_alloc_element(ctx, section, name, strlen(type) + 1);
 192         uci_list_init(&s->options);
 193         s->type = uci_dataptr(s);
 194         s->package = p;
 195         strcpy(s->type, type);
 196         if (name == NULL)
 197                 s->anonymous = true;
 198         p->n_section++;
 199
 200         uci_list_add(&p->sections, &s->e.list);
 201
 202         return s;
 203 }
 204
 205 static void
 206 uci_free_section(struct uci_section *s)
 207 {
 208         struct uci_element *o, *tmp;
 209
 210         uci_foreach_element_safe(&s->options, tmp, o) {
 211                 uci_free_option(uci_to_option(o));
 212         }
 213         if ((s->type != uci_dataptr(s)) &&
 214                 (s->type != NULL))
 215                 free(s->type);
 216         uci_free_element(&s->e);
 217 }
 218
 219 __plugin struct uci_package *
 220 uci_alloc_package(struct uci_context *ctx, const char *name)
 221 {
 222         struct uci_package *p;
 223
 224         p = uci_alloc_element(ctx, package, name, 0);
 225         p->ctx = ctx;
 226         uci_list_init(&p->sections);
 227         uci_list_init(&p->history);
 228         uci_list_init(&p->saved_history);
 229         return p;
 230 }
 231
 232 static void
 233 uci_free_package(struct uci_package **package)
 234 {
 235         struct uci_element *e, *tmp;
 236         struct uci_package *p = *package;
 237
 238         if(!p)
 239                 return;
 240
 241         if (p->path)
 242                 free(p->path);
 243         uci_foreach_element_safe(&p->sections, tmp, e) {
 244                 uci_free_section(uci_to_section(e));
 245         }
 246         uci_foreach_element_safe(&p->history, tmp, e) {
 247                 uci_free_history(uci_to_history(e));
 248         }
 249         uci_foreach_element_safe(&p->saved_history, tmp, e) {
 250                 uci_free_history(uci_to_history(e));
 251         }
 252         uci_free_element(&p->e);
 253         *package = NULL;
 254 }
 255
 256 static struct uci_element *uci_lookup_list(struct uci_list *list, const char *name)
 257 {
 258         struct uci_element *e;
 259
 260         uci_foreach_element(list, e) {
 261                 if (!strcmp(e->name, name))
 262                         return e;
 263         }
 264         return NULL;
 265 }
 266
 267 int uci_lookup_ext(struct uci_context *ctx, struct uci_element **res, char *str)
 268 {
 269         struct uci_package *p = NULL;
 270         struct uci_element *e;
 271         struct uci_section *s;
 272         struct uci_ptr ptr;
 273         char *idxstr, *t;
 274         int idx, c;
 275
 276         UCI_HANDLE_ERR(ctx);
 277         UCI_ASSERT(ctx, res != NULL);
 278         UCI_ASSERT(ctx, str != NULL);
 279
 280         UCI_INTERNAL(uci_parse_ptr, ctx, &ptr, str);
 281
 282         /* look up the package first */
 283         e = uci_lookup_list(&ctx->root, ptr.package);
 284         if (!e) {
 285                 UCI_INTERNAL(uci_load, ctx, ptr.package, &p);
 286                 if (!p)
 287                         goto notfound;
 288                 e = &p->e;
 289         } else {
 290                 p = uci_to_package(e);
 291         }
 292
 293         if (!ptr.section)
 294                 goto done;
 295
 296         /* if the section name validates as a regular name, pass through
 297          * to the regular uci_lookup function call */
 298         if (!(ptr.flags & UCI_LOOKUP_EXTENDED)) {
 299                 UCI_INTERNAL(uci_lookup, ctx, &e, p, ptr.section, ptr.option);
 300                 goto done;
 301         }
 302
 303         /* name did not validate, that means we have an extended lookup call
 304          * parse it here. for now only the section index syntax is supported */
 305         if (ptr.section[0] != '@')
 306                 goto error;
 307
 308         ptr.section++;
 309
 310         /* parse the section index part */
 311         idxstr = strchr(ptr.section, '[');
 312         if (!idxstr)
 313                 goto error;
 314         *idxstr = 0;
 315         idxstr++;
 316
 317         t = strchr(idxstr, ']');
 318         if (!t)
 319                 goto error;
 320         if (t[1] != 0)
 321                 goto error;
 322         *t = 0;
 323
 324         t = NULL;
 325         idx = strtol(idxstr, &t, 10);
 326         if (t && *t)
 327                 goto error;
 328
 329         if (!*ptr.section)
 330                 ptr.section = NULL;
 331         if (ptr.section && !uci_validate_str(ptr.section, false))
 332                 goto error;
 333
 334         /* if the given index is negative, it specifies the section number from
 335          * the end of the list */
 336         if (idx < 0) {
 337                 c = 0;
 338                 uci_foreach_element(&p->sections, e) {
 339                         s = uci_to_section(e);
 340                         if (ptr.section && (strcmp(s->type, ptr.section) != 0))
 341                                 continue;
 342
 343                         c++;
 344                 }
 345                 idx += c;
 346         }
 347
 348         c = 0;
 349         uci_foreach_element(&p->sections, e) {
 350                 s = uci_to_section(e);
 351                 if (ptr.section && (strcmp(s->type, ptr.section) != 0))
 352                         continue;
 353
 354                 if (idx == c)
 355                         goto found;
 356                 c++;
 357         }
 358         goto notfound;
 359
 360 found:
 361         if (ptr.option)
 362                 e = uci_lookup_list(&s->options, ptr.option);
 363 done:
 364         *res = e;
 365         return 0;
 366
 367 notfound:
 368         UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 369 error:
 370         UCI_THROW(ctx, UCI_ERR_INVAL);
 371         return 0;
 372 }
 373
 374 int uci_lookup(struct uci_context *ctx, struct uci_element **res, struct uci_package *p, const char *section, const char *option)
 375 {
 376         struct uci_element *e;
 377         struct uci_section *s;
 378
 379         UCI_HANDLE_ERR(ctx);
 380         UCI_ASSERT(ctx, res != NULL);
 381         UCI_ASSERT(ctx, p != NULL);
 382         UCI_ASSERT(ctx, section && uci_validate_name(section));
 383         if (option)
 384                 UCI_ASSERT(ctx, uci_validate_name(option));
 385
 386         e = uci_lookup_list(&p->sections, section);
 387         if (!e)
 388                 goto notfound;
 389
 390         if (option) {
 391                 s = uci_to_section(e);
 392                 e = uci_lookup_list(&s->options, option);
 393                 if (!e)
 394                         goto notfound;
 395         }
 396
 397         *res = e;
 398         return 0;
 399
 400 notfound:
 401         UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 402         return 0;
 403 }
 404
 405 int uci_del_element(struct uci_context *ctx, struct uci_element *e)
 406 {
 407         /* NB: UCI_INTERNAL use means without history tracking */
 408         bool internal = ctx->internal;
 409         struct uci_package *p = NULL;
 410         struct uci_section *s = NULL;
 411         struct uci_option *o = NULL;
 412         struct uci_element *i, *tmp;
 413         char *option = NULL;
 414
 415         UCI_HANDLE_ERR(ctx);
 416         UCI_ASSERT(ctx, e != NULL);
 417
 418         switch(e->type) {
 419         case UCI_TYPE_SECTION:
 420                 s = uci_to_section(e);
 421                 uci_foreach_element_safe(&s->options, tmp, i) {
 422                         uci_del_element(ctx, i);
 423                 }
 424                 break;
 425         case UCI_TYPE_OPTION:
 426                 o = uci_to_option(e);
 427                 s = o->section;
 428                 p = s->package;
 429                 option = e->name;
 430                 break;
 431         default:
 432                 UCI_THROW(ctx, UCI_ERR_INVAL);
 433                 break;
 434         }
 435
 436         p = s->package;
 437         if (!internal && p->has_history)
 438                 uci_add_history(ctx, &p->history, UCI_CMD_REMOVE, s->e.name, option, NULL);
 439
 440         switch(e->type) {
 441         case UCI_TYPE_SECTION:
 442                 uci_free_section(s);
 443                 break;
 444         case UCI_TYPE_OPTION:
 445                 uci_free_option(o);
 446                 break;
 447         default:
 448                 break;
 449         }
 450
 451         return 0;
 452 }
 453
 454 int uci_add_element_list(struct uci_context *ctx, struct uci_option *o, const char *value)
 455 {
 456         struct uci_element *e;
 457         struct uci_package *p;
 458         struct uci_section *s;
 459         bool internal = ctx->internal;
 460
 461         UCI_HANDLE_ERR(ctx);
 462         UCI_ASSERT(ctx, (o != NULL) && (o->type == UCI_TYPE_LIST) && uci_validate_text(value));
 463
 464         s = o->section;
 465         p = s->package;
 466
 467         if (!internal && p->has_history)
 468                 uci_add_history(ctx, &p->history, UCI_CMD_LIST_ADD, s->e.name, o->e.name, value);
 469
 470         e = uci_alloc_generic(ctx, UCI_TYPE_ITEM, value, sizeof(struct uci_option));
 471         uci_list_add(&o->v.list, &e->list);
 472
 473         return 0;
 474 }
 475
 476 int uci_set_element_value(struct uci_context *ctx, struct uci_element **element, const char *value)
 477 {
 478         /* NB: UCI_INTERNAL use means without history tracking */
 479         bool internal = ctx->internal;
 480         struct uci_list *list;
 481         struct uci_element *e;
 482         struct uci_package *p;
 483         struct uci_section *s;
 484         struct uci_option *o;
 485         char *section;
 486         char *option;
 487         char *str;
 488         int size = 0;
 489
 490         UCI_HANDLE_ERR(ctx);
 491         UCI_ASSERT(ctx, (element != NULL) && (*element != NULL));
 492
 493         /* what the 'value' of an element means depends on the type
 494          * for a section, the 'value' means its type
 495          * for an option, the 'value' means its value string
 496          * when changing the value, shrink the element to its actual size
 497          * (it may have been allocated with a bigger size, to include
 498          *  its buffer)
 499          * then duplicate the string passed on the command line and
 500          * insert it into the structure.
 501          */
 502         e = *element;
 503         list = e->list.prev;
 504
 505         switch(e->type) {
 506         case UCI_TYPE_SECTION:
 507                 UCI_ASSERT(ctx, uci_validate_str(value, false));
 508                 size = sizeof(struct uci_section);
 509                 s = uci_to_section(e);
 510                 section = e->name;
 511                 option = NULL;
 512                 /* matches the currently set value */
 513                 if (!strcmp(value, s->type))
 514                         return 0;
 515                 break;
 516
 517         case UCI_TYPE_OPTION:
 518                 UCI_ASSERT(ctx, value != NULL);
 519                 o = uci_to_option(e);
 520                 s = o->section;
 521                 section = s->e.name;
 522                 option = o->e.name;
 523                 switch(o->type) {
 524                 case UCI_TYPE_STRING:
 525                         size = sizeof(struct uci_option);
 526                         /* matches the currently set value */
 527                         if (!strcmp(value, o->v.string))
 528                                 return 0;
 529                         break;
 530                 default:
 531                         /* default action for non-string datatypes is to delete
 532                          * the existing entry, then re-create it as a string */
 533                         break;
 534                 }
 535                 break;
 536
 537         default:
 538                 UCI_THROW(ctx, UCI_ERR_INVAL);
 539                 return 0;
 540         }
 541         p = s->package;
 542         if (!internal && p->has_history)
 543                 uci_add_history(ctx, &p->history, UCI_CMD_CHANGE, section, option, value);
 544
 545         if ((e->type == UCI_TYPE_OPTION) && (size == 0)) {
 546                 o = uci_alloc_option(s, option, value);
 547                 UCI_INTERNAL(uci_del_element, ctx, e);
 548                 *element = &o->e;
 549                 goto done;
 550         }
 551
 552         uci_list_del(&e->list);
 553         e = uci_realloc(ctx, e, size);
 554         str = uci_strdup(ctx, value);
 555         uci_list_insert(list, &e->list);
 556         *element = e;
 557
 558         switch(e->type) {
 559         case UCI_TYPE_SECTION:
 560                 uci_to_section(e)->type = str;
 561                 break;
 562         case UCI_TYPE_OPTION:
 563                 uci_to_option(e)->v.string = str;
 564                 break;
 565         default:
 566                 break;
 567         }
 568
 569 done:
 570         return 0;
 571 }
 572
 573 int uci_rename(struct uci_context *ctx, struct uci_package *p, char *section, char *option, char *name)
 574 {
 575         /* NB: UCI_INTERNAL use means without history tracking */
 576         bool internal = ctx->internal;
 577         struct uci_element *e;
 578
 579         UCI_HANDLE_ERR(ctx);
 580
 581         /* NB: p, section, option validated by uci_lookup */
 582         UCI_INTERNAL(uci_lookup, ctx, &e, p, section, option);
 583
 584         if (!internal && p->has_history)
 585                 uci_add_history(ctx, &p->history, UCI_CMD_RENAME, section, option, name);
 586
 587         name = uci_strdup(ctx, name);
 588         if (e->name)
 589                 free(e->name);
 590         e->name = name;
 591
 592         return 0;
 593 }
 594
 595 int uci_add_section(struct uci_context *ctx, struct uci_package *p, const char *type, struct uci_section **res)
 596 {
 597         bool internal = ctx->internal;
 598         struct uci_section *s;
 599
 600         UCI_HANDLE_ERR(ctx);
 601         UCI_ASSERT(ctx, p != NULL);
 602         s = uci_alloc_section(p, type, NULL);
 603         uci_fixup_section(ctx, s);
 604         *res = s;
 605         if (!internal && p->has_history)
 606                 uci_add_history(ctx, &p->history, UCI_CMD_ADD, s->e.name, NULL, type);
 607
 608         return 0;
 609 }
 610
 611 int uci_delete(struct uci_context *ctx, struct uci_package *p, const char *section, const char *option)
 612 {
 613         /* NB: pass on internal flag to uci_del_element */
 614         bool internal = ctx->internal;
 615         struct uci_element *e;
 616
 617         UCI_HANDLE_ERR(ctx);
 618
 619         /* NB: p, section, option validated by uci_lookup */
 620         UCI_INTERNAL(uci_lookup, ctx, &e, p, section, option);
 621
 622         ctx->internal = internal;
 623         return uci_del_element(ctx, e);
 624 }
 625
 626 int uci_add_list(struct uci_context *ctx, struct uci_package *p, const char *section, const char *option, const char *value, struct uci_option **result)
 627 {
 628         /* NB: UCI_INTERNAL use means without history tracking */
 629         bool internal = ctx->internal;
 630         struct uci_element *e;
 631         struct uci_section *s;
 632         struct uci_option *o;
 633         struct uci_option *prev = NULL;
 634         const char *value2 = NULL;
 635
 636         UCI_HANDLE_ERR(ctx);
 637         UCI_ASSERT(ctx, p && section && option && value && uci_validate_text(value));
 638
 639         /* look up the section first */
 640         UCI_INTERNAL(uci_lookup, ctx, &e, p, section, NULL);
 641         s = uci_to_section(e);
 642
 643         e = uci_lookup_list(&s->options, option);
 644         if (e) {
 645                 o = uci_to_option(e);
 646                 switch (o->type) {
 647                 case UCI_TYPE_STRING:
 648                         /* we already have a string value, let's convert that to a list */
 649                         prev = o;
 650                         value2 = value;
 651                         value = o->v.string;
 652                         break;
 653                 case UCI_TYPE_LIST:
 654                         if (result)
 655                                 *result = o;
 656
 657                         ctx->internal = internal;
 658                         return uci_add_element_list(ctx, o, value);
 659                 default:
 660                         UCI_THROW(ctx, UCI_ERR_INVAL);
 661                         break;
 662                 }
 663         }
 664
 665         o = uci_alloc_list(s, option);
 666         if (result)
 667                 *result = o;
 668         if (prev) {
 669                 UCI_INTERNAL(uci_add_element_list, ctx, o, value);
 670                 uci_free_option(prev);
 671                 value = value2;
 672         }
 673
 674         ctx->internal = internal;
 675         return uci_add_element_list(ctx, o, value);
 676 }
 677
 678 int uci_set(struct uci_context *ctx, struct uci_package *p, const char *section, const char *option, const char *value, struct uci_element **result)
 679 {
 680         /* NB: UCI_INTERNAL use means without history tracking */
 681         bool internal = ctx->internal;
 682         struct uci_element *e = NULL;
 683         struct uci_section *s = NULL;
 684         struct uci_option *o = NULL;
 685
 686         UCI_HANDLE_ERR(ctx);
 687         UCI_ASSERT(ctx, p != NULL);
 688         UCI_ASSERT(ctx, uci_validate_name(section));
 689         if (option) {
 690                 UCI_ASSERT(ctx, uci_validate_name(option));
 691                 UCI_ASSERT(ctx, value != NULL);
 692         } else {
 693                 UCI_ASSERT(ctx, uci_validate_str(value, false));
 694         }
 695
 696         /*
 697          * look up the package, section and option (if set)
 698          * if the section/option is to be modified and it is not found
 699          * create a new element in the appropriate list
 700          */
 701         e = uci_lookup_list(&p->sections, section);
 702         if (!e)
 703                 goto notfound;
 704
 705         s = uci_to_section(e);
 706         if (ctx->pctx && ctx->pctx->merge)
 707                 ctx->pctx->section = s;
 708
 709         if (option) {
 710                 e = uci_lookup_list(&s->options, option);
 711                 if (!e)
 712                         goto notfound;
 713                 o = uci_to_option(e);
 714         }
 715
 716         /*
 717          * no unknown element was supplied, assume that we can just update
 718          * an existing entry
 719          */
 720         if (o)
 721                 e = &o->e;
 722         else
 723                 e = &s->e;
 724         if (result)
 725                 *result = e;
 726         else
 727                 result = &e;
 728
 729         ctx->internal = internal;
 730         return uci_set_element_value(ctx, result, value);
 731
 732 notfound:
 733         /*
 734          * the entry that we need to update was not found,
 735          * check if the search failed prematurely.
 736          * this can happen if the package was not found, or if
 737          * an option was supplied, but the section wasn't found
 738          */
 739         if (!p || (!s && option))
 740                 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 741
 742         /* now add the missing entry */
 743         if (!internal && p->has_history)
 744                 uci_add_history(ctx, &p->history, UCI_CMD_CHANGE, section, option, value);
 745         if (s) {
 746                 o = uci_alloc_option(s, option, value);
 747                 if (result)
 748                         *result = &o->e;
 749         } else {
 750                 s = uci_alloc_section(p, value, section);
 751                 if (result)
 752                         *result = &s->e;
 753                 if (ctx->pctx && ctx->pctx->merge)
 754                         ctx->pctx->section = s;
 755         }
 756
 757         return 0;
 758 }
 759
 760 int uci_unload(struct uci_context *ctx, struct uci_package *p)
 761 {
 762         UCI_HANDLE_ERR(ctx);
 763         UCI_ASSERT(ctx, p != NULL);
 764
 765         uci_free_package(&p);
 766         return 0;
 767 }
 768