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 Lesser General Public License for more details.
  13  */
  14
  15 static bool uci_list_set_pos(struct uci_list *head, struct uci_list *ptr, int pos)
  16 {
  17         struct uci_list *old_head = ptr->prev;
  18         struct uci_list *new_head = head;
  19         struct uci_element *p = NULL;
  20
  21         uci_list_del(ptr);
  22         uci_foreach_element(head, p) {
  23                 if (pos-- <= 0)
  24                         break;
  25                 new_head = &p->list;
  26         }
  27
  28         uci_list_add(new_head->next, ptr);
  29
  30         return (old_head != new_head);
  31 }
  32
  33 /*
  34  * uci_alloc_generic allocates a new uci_element with payload
  35  * payload is appended to the struct to save memory and reduce fragmentation
  36  */
  37 __private struct uci_element *
  38 uci_alloc_generic(struct uci_context *ctx, int type, const char *name, int size)
  39 {
  40         struct uci_element *e;
  41         int datalen = size;
  42         void *ptr;
  43
  44         ptr = uci_malloc(ctx, datalen);
  45         e = (struct uci_element *) ptr;
  46         e->type = type;
  47         if (name) {
  48                 UCI_TRAP_SAVE(ctx, error);
  49                 e->name = uci_strdup(ctx, name);
  50                 UCI_TRAP_RESTORE(ctx);
  51         }
  52         uci_list_init(&e->list);
  53         goto done;
  54
  55 error:
  56         free(ptr);
  57         UCI_THROW(ctx, ctx->err);
  58
  59 done:
  60         return e;
  61 }
  62
  63 __private void
  64 uci_free_element(struct uci_element *e)
  65 {
  66         free(e->name);
  67         if (!uci_list_empty(&e->list))
  68                 uci_list_del(&e->list);
  69         free(e);
  70 }
  71
  72 static struct uci_option *
  73 uci_alloc_option(struct uci_section *s, const char *name, const char *value, struct uci_list *after)
  74 {
  75         struct uci_package *p = s->package;
  76         struct uci_context *ctx = p->ctx;
  77         struct uci_option *o;
  78
  79         o = uci_alloc_element(ctx, option, name, strlen(value) + 1);
  80         o->type = UCI_TYPE_STRING;
  81         o->v.string = uci_dataptr(o);
  82         o->section = s;
  83         strcpy(o->v.string, value);
  84         uci_list_insert(after ? after : s->options.prev, &o->e.list);
  85
  86         return o;
  87 }
  88
  89 static inline void
  90 uci_free_option(struct uci_option *o)
  91 {
  92         struct uci_element *e, *tmp;
  93
  94         switch(o->type) {
  95         case UCI_TYPE_STRING:
  96                 if ((o->v.string != uci_dataptr(o)) &&
  97                         (o->v.string != NULL))
  98                         free(o->v.string);
  99                 break;
 100         case UCI_TYPE_LIST:
 101                 uci_foreach_element_safe(&o->v.list, tmp, e) {
 102                         uci_free_element(e);
 103                 }
 104                 break;
 105         default:
 106                 break;
 107         }
 108         uci_free_element(&o->e);
 109 }
 110
 111 static struct uci_option *
 112 uci_alloc_list(struct uci_section *s, const char *name, struct uci_list *after)
 113 {
 114         struct uci_package *p = s->package;
 115         struct uci_context *ctx = p->ctx;
 116         struct uci_option *o;
 117
 118         o = uci_alloc_element(ctx, option, name, 0);
 119         o->type = UCI_TYPE_LIST;
 120         o->section = s;
 121         uci_list_init(&o->v.list);
 122         uci_list_insert(after ? after : s->options.prev, &o->e.list);
 123
 124         return o;
 125 }
 126
 127 /* Based on an efficient hash function published by D. J. Bernstein */
 128 static unsigned int djbhash(unsigned int hash, char *str)
 129 {
 130         int len = strlen(str);
 131         int i;
 132
 133         /* initial value */
 134         if (hash == ~0U)
 135                 hash = 5381;
 136
 137         for(i = 0; i < len; i++) {
 138                 hash = ((hash << 5) + hash) + str[i];
 139         }
 140         return (hash & 0x7FFFFFFF);
 141 }
 142
 143 /* fix up an unnamed section, e.g. after adding options to it */
 144 static void uci_fixup_section(struct uci_context *ctx, struct uci_section *s)
 145 {
 146         unsigned int hash = ~0U;
 147         struct uci_element *e;
 148         char buf[16];
 149
 150         if (!s || s->e.name)
 151                 return;
 152
 153         /*
 154          * Generate a name for unnamed sections. This is used as reference
 155          * when locating or updating the section from apps/scripts.
 156          * To make multiple concurrent versions somewhat safe for updating,
 157          * the name is generated from a hash of its type and name/value
 158          * pairs of its option, and it is prefixed by a counter value.
 159          * If the order of the unnamed sections changes for some reason,
 160          * updates to them will be rejected.
 161          */
 162         hash = djbhash(hash, s->type);
 163         uci_foreach_element(&s->options, e) {
 164                 struct uci_option *o;
 165                 hash = djbhash(hash, e->name);
 166                 o = uci_to_option(e);
 167                 switch(o->type) {
 168                 case UCI_TYPE_STRING:
 169                         hash = djbhash(hash, o->v.string);
 170                         break;
 171                 default:
 172                         break;
 173                 }
 174         }
 175         sprintf(buf, "cfg%02x%04x", s->package->n_section, hash % (1 << 16));
 176         s->e.name = uci_strdup(ctx, buf);
 177 }
 178
 179 /* transfer options between two sections */
 180 static void uci_section_transfer_options(struct uci_section *dst, struct uci_section *src)
 181 {
 182         struct uci_element *e;
 183
 184         /* transfer the option list by inserting the new list HEAD and removing the old */
 185         uci_list_insert(&src->options, &dst->options);
 186         uci_list_del(&src->options);
 187
 188         /* update pointer to section in options */
 189         uci_foreach_element(&dst->options, e) {
 190                 struct uci_option *o;
 191
 192                 o = uci_to_option(e);
 193                 o->section = dst;
 194         }
 195 }
 196
 197 static struct uci_section *
 198 uci_alloc_section(struct uci_package *p, const char *type, const char *name, struct uci_list *after)
 199 {
 200         struct uci_context *ctx = p->ctx;
 201         struct uci_section *s;
 202
 203         if (name && !name[0])
 204                 name = NULL;
 205
 206         s = uci_alloc_element(ctx, section, name, strlen(type) + 1);
 207         uci_list_init(&s->options);
 208         s->type = uci_dataptr(s);
 209         s->package = p;
 210         strcpy(s->type, type);
 211         if (name == NULL)
 212                 s->anonymous = true;
 213         p->n_section++;
 214
 215         uci_list_insert(after ? after : p->sections.prev, &s->e.list);
 216
 217         return s;
 218 }
 219
 220 static void
 221 uci_free_section(struct uci_section *s)
 222 {
 223         struct uci_element *o, *tmp;
 224
 225         uci_foreach_element_safe(&s->options, tmp, o) {
 226                 uci_free_option(uci_to_option(o));
 227         }
 228         if ((s->type != uci_dataptr(s)) &&
 229                 (s->type != NULL))
 230                 free(s->type);
 231         uci_free_element(&s->e);
 232 }
 233
 234 __private struct uci_package *
 235 uci_alloc_package(struct uci_context *ctx, const char *name)
 236 {
 237         struct uci_package *p;
 238
 239         p = uci_alloc_element(ctx, package, name, 0);
 240         p->ctx = ctx;
 241         uci_list_init(&p->sections);
 242         uci_list_init(&p->delta);
 243         uci_list_init(&p->saved_delta);
 244         return p;
 245 }
 246
 247 __private void
 248 uci_free_package(struct uci_package **package)
 249 {
 250         struct uci_element *e, *tmp;
 251         struct uci_package *p = *package;
 252
 253         if(!p)
 254                 return;
 255
 256         free(p->path);
 257         uci_foreach_element_safe(&p->sections, tmp, e) {
 258                 uci_free_section(uci_to_section(e));
 259         }
 260         uci_foreach_element_safe(&p->delta, tmp, e) {
 261                 uci_free_delta(uci_to_delta(e));
 262         }
 263         uci_foreach_element_safe(&p->saved_delta, tmp, e) {
 264                 uci_free_delta(uci_to_delta(e));
 265         }
 266         uci_free_element(&p->e);
 267         *package = NULL;
 268 }
 269
 270 static void
 271 uci_free_any(struct uci_element **e)
 272 {
 273         switch((*e)->type) {
 274         case UCI_TYPE_SECTION:
 275                 uci_free_section(uci_to_section(*e));
 276                 break;
 277         case UCI_TYPE_OPTION:
 278                 uci_free_option(uci_to_option(*e));
 279                 break;
 280         default:
 281                 break;
 282         }
 283         *e = NULL;
 284 }
 285
 286 __private struct uci_element *
 287 uci_lookup_list(struct uci_list *list, const char *name)
 288 {
 289         struct uci_element *e;
 290
 291         uci_foreach_element(list, e) {
 292                 if (!strcmp(e->name, name))
 293                         return e;
 294         }
 295         return NULL;
 296 }
 297
 298 static struct uci_element *
 299 uci_lookup_ext_section(struct uci_context *ctx, struct uci_ptr *ptr)
 300 {
 301         char *idxstr, *t, *section, *name;
 302         struct uci_element *e = NULL;
 303         struct uci_section *s;
 304         int idx, c;
 305
 306         section = uci_strdup(ctx, ptr->section);
 307         name = idxstr = section + 1;
 308
 309         if (section[0] != '@')
 310                 goto error;
 311
 312         /* parse the section index part */
 313         idxstr = strchr(idxstr, '[');
 314         if (!idxstr)
 315                 goto error;
 316         *idxstr = 0;
 317         idxstr++;
 318
 319         t = strchr(idxstr, ']');
 320         if (!t)
 321                 goto error;
 322         if (t[1] != 0)
 323                 goto error;
 324         *t = 0;
 325
 326         t = NULL;
 327         idx = strtol(idxstr, &t, 10);
 328         if (t && *t)
 329                 goto error;
 330
 331         if (!*name)
 332                 name = NULL;
 333         else if (!uci_validate_type(name))
 334                 goto error;
 335
 336         /* if the given index is negative, it specifies the section number from
 337          * the end of the list */
 338         if (idx < 0) {
 339                 c = 0;
 340                 uci_foreach_element(&ptr->p->sections, e) {
 341                         s = uci_to_section(e);
 342                         if (name && (strcmp(s->type, name) != 0))
 343                                 continue;
 344
 345                         c++;
 346                 }
 347                 idx += c;
 348         }
 349
 350         c = 0;
 351         uci_foreach_element(&ptr->p->sections, e) {
 352                 s = uci_to_section(e);
 353                 if (name && (strcmp(s->type, name) != 0))
 354                         continue;
 355
 356                 if (idx == c)
 357                         goto done;
 358                 c++;
 359         }
 360         e = NULL;
 361         goto done;
 362
 363 error:
 364         free(section);
 365         memset(ptr, 0, sizeof(struct uci_ptr));
 366         UCI_THROW(ctx, UCI_ERR_INVAL);
 367 done:
 368         free(section);
 369         if (e)
 370                 ptr->section = e->name;
 371         return e;
 372 }
 373
 374 int
 375 uci_lookup_next(struct uci_context *ctx, struct uci_element **e, struct uci_list *list, const char *name)
 376 {
 377         UCI_HANDLE_ERR(ctx);
 378
 379         *e = uci_lookup_list(list, name);
 380         if (!*e)
 381                 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 382
 383         return 0;
 384 }
 385
 386 int
 387 uci_lookup_ptr(struct uci_context *ctx, struct uci_ptr *ptr, char *str, bool extended)
 388 {
 389         struct uci_element *e;
 390
 391         UCI_HANDLE_ERR(ctx);
 392         UCI_ASSERT(ctx, ptr != NULL);
 393
 394         if (str)
 395                 UCI_INTERNAL(uci_parse_ptr, ctx, ptr, str);
 396
 397         ptr->flags |= UCI_LOOKUP_DONE;
 398
 399         /* look up the package first */
 400         if (ptr->p)
 401                 e = &ptr->p->e;
 402         else
 403                 e = uci_lookup_list(&ctx->root, ptr->package);
 404
 405         if (!e) {
 406                 UCI_INTERNAL(uci_load, ctx, ptr->package, &ptr->p);
 407                 if (!ptr->p)
 408                         goto notfound;
 409                 ptr->last = &ptr->p->e;
 410         } else {
 411                 ptr->p = uci_to_package(e);
 412                 ptr->last = e;
 413         }
 414
 415         if (!ptr->section && !ptr->s)
 416                 goto complete;
 417
 418         /* if the section name validates as a regular name, pass through
 419          * to the regular uci_lookup function call */
 420         if (ptr->s) {
 421                 e = &ptr->s->e;
 422         } else if (ptr->flags & UCI_LOOKUP_EXTENDED) {
 423                 if (extended)
 424                         e = uci_lookup_ext_section(ctx, ptr);
 425                 else
 426                         UCI_THROW(ctx, UCI_ERR_INVAL);
 427         } else {
 428                 e = uci_lookup_list(&ptr->p->sections, ptr->section);
 429         }
 430
 431         if (!e)
 432                 goto abort;
 433
 434         ptr->last = e;
 435         ptr->s = uci_to_section(e);
 436
 437         if (ptr->option) {
 438                 e = uci_lookup_list(&ptr->s->options, ptr->option);
 439                 if (!e)
 440                         goto abort;
 441
 442                 ptr->o = uci_to_option(e);
 443                 ptr->last = e;
 444         }
 445
 446 complete:
 447         ptr->flags |= UCI_LOOKUP_COMPLETE;
 448 abort:
 449         return UCI_OK;
 450
 451 notfound:
 452         UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 453         /* not a chance here */
 454         return UCI_ERR_NOTFOUND;
 455 }
 456
 457 __private struct uci_element *
 458 uci_expand_ptr(struct uci_context *ctx, struct uci_ptr *ptr, bool complete)
 459 {
 460         UCI_ASSERT(ctx, ptr != NULL);
 461
 462         if (!(ptr->flags & UCI_LOOKUP_DONE))
 463                 UCI_INTERNAL(uci_lookup_ptr, ctx, ptr, NULL, 1);
 464         if (complete && !(ptr->flags & UCI_LOOKUP_COMPLETE))
 465                 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 466         UCI_ASSERT(ctx, ptr->p != NULL);
 467
 468         /* fill in missing string info */
 469         if (ptr->p && !ptr->package)
 470                 ptr->package = ptr->p->e.name;
 471         if (ptr->s && !ptr->section)
 472                 ptr->section = ptr->s->e.name;
 473         if (ptr->o && !ptr->option)
 474                 ptr->option = ptr->o->e.name;
 475
 476         if (ptr->o)
 477                 return &ptr->o->e;
 478         if (ptr->s)
 479                 return &ptr->s->e;
 480         if (ptr->p)
 481                 return &ptr->p->e;
 482         else
 483                 return NULL;
 484 }
 485
 486 int uci_rename(struct uci_context *ctx, struct uci_ptr *ptr)
 487 {
 488         /* NB: UCI_INTERNAL use means without delta tracking */
 489         bool internal = ctx && ctx->internal;
 490         struct uci_element *e;
 491         struct uci_package *p;
 492         char *n;
 493
 494         UCI_HANDLE_ERR(ctx);
 495
 496         e = uci_expand_ptr(ctx, ptr, true);
 497         p = ptr->p;
 498
 499         UCI_ASSERT(ctx, ptr->s);
 500         UCI_ASSERT(ctx, ptr->value);
 501
 502         if (!internal && p->has_delta)
 503                 uci_add_delta(ctx, &p->delta, UCI_CMD_RENAME, ptr->section, ptr->option, ptr->value);
 504
 505         n = uci_strdup(ctx, ptr->value);
 506         free(e->name);
 507         e->name = n;
 508
 509         if (e->type == UCI_TYPE_SECTION)
 510                 uci_to_section(e)->anonymous = false;
 511
 512         return 0;
 513 }
 514
 515 int uci_reorder_section(struct uci_context *ctx, struct uci_section *s, int pos)
 516 {
 517         struct uci_package *p = s->package;
 518         bool internal = ctx && ctx->internal;
 519         bool changed = false;
 520         char order[32];
 521
 522         UCI_HANDLE_ERR(ctx);
 523
 524         changed = uci_list_set_pos(&s->package->sections, &s->e.list, pos);
 525         if (!internal && p->has_delta && changed) {
 526                 sprintf(order, "%d", pos);
 527                 uci_add_delta(ctx, &p->delta, UCI_CMD_REORDER, s->e.name, NULL, order);
 528         }
 529
 530         return 0;
 531 }
 532
 533 int uci_add_section(struct uci_context *ctx, struct uci_package *p, const char *type, struct uci_section **res)
 534 {
 535         bool internal = ctx && ctx->internal;
 536         struct uci_section *s;
 537
 538         UCI_HANDLE_ERR(ctx);
 539         UCI_ASSERT(ctx, p != NULL);
 540         s = uci_alloc_section(p, type, NULL, NULL);
 541         if (s && s->anonymous)
 542                 uci_fixup_section(ctx, s);
 543         *res = s;
 544         if (!internal && p->has_delta)
 545                 uci_add_delta(ctx, &p->delta, UCI_CMD_ADD, s->e.name, NULL, type);
 546
 547         return 0;
 548 }
 549
 550 int uci_delete(struct uci_context *ctx, struct uci_ptr *ptr)
 551 {
 552         /* NB: pass on internal flag to uci_del_element */
 553         bool internal = ctx && ctx->internal;
 554         struct uci_package *p;
 555         struct uci_element *e1, *e2, *tmp;
 556         int index;
 557
 558         UCI_HANDLE_ERR(ctx);
 559
 560         e1 = uci_expand_ptr(ctx, ptr, true);
 561         p = ptr->p;
 562
 563         UCI_ASSERT(ctx, ptr->s);
 564
 565         if (ptr->o && ptr->o->type == UCI_TYPE_LIST && ptr->value && *ptr->value) {
 566                 if (!sscanf(ptr->value, "%d", &index))
 567                         return 1;
 568
 569                 uci_foreach_element_safe(&ptr->o->v.list, tmp, e2) {
 570                         if (index == 0) {
 571                                 if (!internal && p->has_delta)
 572                                         uci_add_delta(ctx, &p->delta, UCI_CMD_REMOVE, ptr->section, ptr->option, ptr->value);
 573                                 uci_free_option(uci_to_option(e2));
 574                                 return 0;
 575                         }
 576                         index--;
 577                 }
 578
 579                 return 0;
 580         }
 581
 582         if (!internal && p->has_delta)
 583                 uci_add_delta(ctx, &p->delta, UCI_CMD_REMOVE, ptr->section, ptr->option, NULL);
 584
 585         uci_free_any(&e1);
 586
 587         if (ptr->option)
 588                 ptr->o = NULL;
 589         else if (ptr->section)
 590                 ptr->s = NULL;
 591
 592         return 0;
 593 }
 594
 595 int uci_add_list(struct uci_context *ctx, struct uci_ptr *ptr)
 596 {
 597         /* NB: UCI_INTERNAL use means without delta tracking */
 598         bool internal = ctx && ctx->internal;
 599         struct uci_element *volatile e1 = NULL, *volatile e2 = NULL;
 600
 601         UCI_HANDLE_ERR(ctx);
 602
 603         uci_expand_ptr(ctx, ptr, false);
 604         UCI_ASSERT(ctx, ptr->s);
 605         UCI_ASSERT(ctx, ptr->value);
 606
 607         if (ptr->o && ptr->o->type != UCI_TYPE_LIST && ptr->o->type != UCI_TYPE_STRING) {
 608                 UCI_THROW(ctx, UCI_ERR_INVAL);
 609         }
 610
 611         /* create new item */
 612         e1 = uci_alloc_generic(ctx, UCI_TYPE_ITEM, ptr->value, sizeof(struct uci_option));
 613
 614         if (!ptr->o) {
 615                 /* create new list */
 616                 UCI_TRAP_SAVE(ctx, error);
 617                 ptr->o = uci_alloc_list(ptr->s, ptr->option, NULL);
 618                 UCI_TRAP_RESTORE(ctx);
 619         } else if (ptr->o->type == UCI_TYPE_STRING) {
 620                 /* create new list and add old string value as item to list */
 621                 struct uci_option *old = ptr->o;
 622                 UCI_TRAP_SAVE(ctx, error);
 623                 e2 = uci_alloc_generic(ctx, UCI_TYPE_ITEM, old->v.string, sizeof(struct uci_option));
 624                 ptr->o = uci_alloc_list(ptr->s, ptr->option, &old->e.list);
 625                 UCI_TRAP_RESTORE(ctx);
 626                 uci_list_add(&ptr->o->v.list, &e2->list);
 627
 628                 /* remove old option */
 629                 if (ptr->option == old->e.name)
 630                         ptr->option = ptr->o->e.name;
 631                 uci_free_option(old);
 632         }
 633
 634         /* add new item to list */
 635         uci_list_add(&ptr->o->v.list, &e1->list);
 636
 637         if (!internal && ptr->p->has_delta)
 638                 uci_add_delta(ctx, &ptr->p->delta, UCI_CMD_LIST_ADD, ptr->section, ptr->option, ptr->value);
 639
 640         return 0;
 641 error:
 642         if (e1 != NULL)
 643                 uci_free_element(e1);
 644         if (e2 != NULL)
 645                 uci_free_element(e2);
 646         UCI_THROW(ctx, ctx->err);
 647 }
 648
 649 int uci_del_list(struct uci_context *ctx, struct uci_ptr *ptr)
 650 {
 651         /* NB: pass on internal flag to uci_del_element */
 652         bool internal = ctx && ctx->internal;
 653         struct uci_element *e, *tmp;
 654         struct uci_package *p;
 655
 656         UCI_HANDLE_ERR(ctx);
 657
 658         uci_expand_ptr(ctx, ptr, false);
 659         UCI_ASSERT(ctx, ptr->s);
 660         UCI_ASSERT(ctx, ptr->value);
 661
 662         if (!(ptr->o && ptr->option))
 663                 return 0;
 664
 665         if ((ptr->o->type != UCI_TYPE_LIST))
 666                 return 0;
 667
 668         p = ptr->p;
 669         if (!internal && p->has_delta)
 670                 uci_add_delta(ctx, &p->delta, UCI_CMD_LIST_DEL, ptr->section, ptr->option, ptr->value);
 671
 672         uci_foreach_element_safe(&ptr->o->v.list, tmp, e) {
 673                 if (!strcmp(ptr->value, uci_to_option(e)->e.name)) {
 674                         uci_free_option(uci_to_option(e));
 675                 }
 676         }
 677
 678         return 0;
 679 }
 680
 681 int uci_set(struct uci_context *ctx, struct uci_ptr *ptr)
 682 {
 683         /* NB: UCI_INTERNAL use means without delta tracking */
 684         bool internal = ctx && ctx->internal;
 685
 686         UCI_HANDLE_ERR(ctx);
 687         uci_expand_ptr(ctx, ptr, false);
 688         UCI_ASSERT(ctx, ptr->value);
 689         UCI_ASSERT(ctx, ptr->s || (!ptr->option && ptr->section));
 690         if (!ptr->option && ptr->value[0]) {
 691                 UCI_ASSERT(ctx, uci_validate_type(ptr->value));
 692         }
 693
 694         if (!ptr->o && ptr->s && ptr->option) {
 695                 struct uci_element *e;
 696                 e = uci_lookup_list(&ptr->s->options, ptr->option);
 697                 if (e)
 698                         ptr->o = uci_to_option(e);
 699         }
 700         if (!ptr->value[0]) {
 701                 /* if setting a nonexistant option/section to a nonexistant value,
 702                  * exit without errors */
 703                 if (!(ptr->flags & UCI_LOOKUP_COMPLETE))
 704                         return 0;
 705
 706                 return uci_delete(ctx, ptr);
 707         } else if (!ptr->o && ptr->option) { /* new option */
 708                 ptr->o = uci_alloc_option(ptr->s, ptr->option, ptr->value, NULL);
 709         } else if (!ptr->s && ptr->section) { /* new section */
 710                 ptr->s = uci_alloc_section(ptr->p, ptr->value, ptr->section, NULL);
 711         } else if (ptr->o && ptr->option) { /* update option */
 712                 if (ptr->o->type == UCI_TYPE_STRING && !strcmp(ptr->o->v.string, ptr->value))
 713                         return 0;
 714
 715                 if (ptr->o->type == UCI_TYPE_STRING && strlen(ptr->o->v.string) == strlen(ptr->value)) {
 716                         strcpy(ptr->o->v.string, ptr->value);
 717                 } else {
 718                         struct uci_option *old = ptr->o;
 719                         ptr->o = uci_alloc_option(ptr->s, ptr->option, ptr->value, &old->e.list);
 720                         if (ptr->option == old->e.name)
 721                                 ptr->option = ptr->o->e.name;
 722                         uci_free_option(old);
 723                 }
 724         } else if (ptr->s && ptr->section) { /* update section */
 725                 if (!strcmp(ptr->s->type, ptr->value))
 726                         return 0;
 727
 728                 if (strlen(ptr->s->type) == strlen(ptr->value)) {
 729                         strcpy(ptr->s->type, ptr->value);
 730                 } else {
 731                         struct uci_section *old = ptr->s;
 732                         ptr->s = uci_alloc_section(ptr->p, ptr->value, old->e.name, &old->e.list);
 733                         uci_section_transfer_options(ptr->s, old);
 734                         if (ptr->section == old->e.name)
 735                                 ptr->section = ptr->s->e.name;
 736                         uci_free_section(old);
 737                         ptr->s->package->n_section--;
 738                 }
 739         } else {
 740                 UCI_THROW(ctx, UCI_ERR_INVAL);
 741         }
 742
 743         if (!internal && ptr->p->has_delta)
 744                 uci_add_delta(ctx, &ptr->p->delta, UCI_CMD_CHANGE, ptr->section, ptr->option, ptr->value);
 745
 746         return 0;
 747 }
 748
 749 int uci_unload(struct uci_context *ctx, struct uci_package *p)
 750 {
 751         UCI_HANDLE_ERR(ctx);
 752         UCI_ASSERT(ctx, p != NULL);
 753
 754         uci_free_package(&p);
 755         return 0;
 756 }
 757