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 void uci_list_set_pos(struct uci_list *head, struct uci_list *ptr, int pos)
  16 {
  17         struct uci_list *new_head = head;
  18         struct uci_element *p = NULL;
  19
  20         uci_list_del(ptr);
  21         uci_foreach_element(head, p) {
  22                 if (pos-- <= 0)
  23                         break;
  24                 new_head = &p->list;
  25         }
  26
  27         uci_list_add(new_head->next, ptr);
  28 }
  29
  30 static inline void uci_list_fixup(struct uci_list *ptr)
  31 {
  32         ptr->prev->next = ptr;
  33         ptr->next->prev = ptr;
  34 }
  35
  36 /*
  37  * uci_alloc_generic allocates a new uci_element with payload
  38  * payload is appended to the struct to save memory and reduce fragmentation
  39  */
  40 __private struct uci_element *
  41 uci_alloc_generic(struct uci_context *ctx, int type, const char *name, int size)
  42 {
  43         struct uci_element *e;
  44         int datalen = size;
  45         void *ptr;
  46
  47         ptr = uci_malloc(ctx, datalen);
  48         e = (struct uci_element *) ptr;
  49         e->type = type;
  50         if (name) {
  51                 UCI_TRAP_SAVE(ctx, error);
  52                 e->name = uci_strdup(ctx, name);
  53                 UCI_TRAP_RESTORE(ctx);
  54         }
  55         uci_list_init(&e->list);
  56         goto done;
  57
  58 error:
  59         free(ptr);
  60         UCI_THROW(ctx, ctx->err);
  61
  62 done:
  63         return e;
  64 }
  65
  66 __private void
  67 uci_free_element(struct uci_element *e)
  68 {
  69         free(e->name);
  70         if (!uci_list_empty(&e->list))
  71                 uci_list_del(&e->list);
  72         free(e);
  73 }
  74
  75 static struct uci_option *
  76 uci_alloc_option(struct uci_section *s, const char *name, const char *value)
  77 {
  78         struct uci_package *p = s->package;
  79         struct uci_context *ctx = p->ctx;
  80         struct uci_option *o;
  81
  82         o = uci_alloc_element(ctx, option, name, strlen(value) + 1);
  83         o->type = UCI_TYPE_STRING;
  84         o->v.string = uci_dataptr(o);
  85         o->section = s;
  86         strcpy(o->v.string, value);
  87         uci_list_add(&s->options, &o->e.list);
  88
  89         return o;
  90 }
  91
  92 static inline void
  93 uci_free_option(struct uci_option *o)
  94 {
  95         struct uci_element *e, *tmp;
  96
  97         switch(o->type) {
  98         case UCI_TYPE_STRING:
  99                 if ((o->v.string != uci_dataptr(o)) &&
 100                         (o->v.string != NULL))
 101                         free(o->v.string);
 102                 break;
 103         case UCI_TYPE_LIST:
 104                 uci_foreach_element_safe(&o->v.list, tmp, e) {
 105                         uci_free_element(e);
 106                 }
 107                 break;
 108         default:
 109                 break;
 110         }
 111         uci_free_element(&o->e);
 112 }
 113
 114 static struct uci_option *
 115 uci_alloc_list(struct uci_section *s, const char *name)
 116 {
 117         struct uci_package *p = s->package;
 118         struct uci_context *ctx = p->ctx;
 119         struct uci_option *o;
 120
 121         o = uci_alloc_element(ctx, option, name, 0);
 122         o->type = UCI_TYPE_LIST;
 123         o->section = s;
 124         uci_list_init(&o->v.list);
 125         uci_list_add(&s->options, &o->e.list);
 126
 127         return o;
 128 }
 129
 130 /* Based on an efficient hash function published by D. J. Bernstein */
 131 static unsigned int djbhash(unsigned int hash, char *str)
 132 {
 133         int len = strlen(str);
 134         int i;
 135
 136         /* initial value */
 137         if (hash == ~0)
 138                 hash = 5381;
 139
 140         for(i = 0; i < len; i++) {
 141                 hash = ((hash << 5) + hash) + str[i];
 142         }
 143         return (hash & 0x7FFFFFFF);
 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 __private 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->delta);
 228         uci_list_init(&p->saved_delta);
 229         return p;
 230 }
 231
 232 __private 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         free(p->path);
 242         uci_foreach_element_safe(&p->sections, tmp, e) {
 243                 uci_free_section(uci_to_section(e));
 244         }
 245         uci_foreach_element_safe(&p->delta, tmp, e) {
 246                 uci_free_delta(uci_to_delta(e));
 247         }
 248         uci_foreach_element_safe(&p->saved_delta, tmp, e) {
 249                 uci_free_delta(uci_to_delta(e));
 250         }
 251         uci_free_element(&p->e);
 252         *package = NULL;
 253 }
 254
 255 static void
 256 uci_free_any(struct uci_element **e)
 257 {
 258         switch((*e)->type) {
 259         case UCI_TYPE_SECTION:
 260                 uci_free_section(uci_to_section(*e));
 261                 break;
 262         case UCI_TYPE_OPTION:
 263                 uci_free_option(uci_to_option(*e));
 264                 break;
 265         default:
 266                 break;
 267         }
 268         *e = NULL;
 269 }
 270
 271 __private struct uci_element *
 272 uci_lookup_list(struct uci_list *list, const char *name)
 273 {
 274         struct uci_element *e;
 275
 276         uci_foreach_element(list, e) {
 277                 if (!strcmp(e->name, name))
 278                         return e;
 279         }
 280         return NULL;
 281 }
 282
 283 static struct uci_element *
 284 uci_lookup_ext_section(struct uci_context *ctx, struct uci_ptr *ptr)
 285 {
 286         char *idxstr, *t, *section, *name;
 287         struct uci_element *e = NULL;
 288         struct uci_section *s;
 289         int idx, c;
 290
 291         section = uci_strdup(ctx, ptr->section);
 292         name = idxstr = section + 1;
 293
 294         if (section[0] != '@')
 295                 goto error;
 296
 297         /* parse the section index part */
 298         idxstr = strchr(idxstr, '[');
 299         if (!idxstr)
 300                 goto error;
 301         *idxstr = 0;
 302         idxstr++;
 303
 304         t = strchr(idxstr, ']');
 305         if (!t)
 306                 goto error;
 307         if (t[1] != 0)
 308                 goto error;
 309         *t = 0;
 310
 311         t = NULL;
 312         idx = strtol(idxstr, &t, 10);
 313         if (t && *t)
 314                 goto error;
 315
 316         if (!*name)
 317                 name = NULL;
 318         else if (!uci_validate_type(name))
 319                 goto error;
 320
 321         /* if the given index is negative, it specifies the section number from
 322          * the end of the list */
 323         if (idx < 0) {
 324                 c = 0;
 325                 uci_foreach_element(&ptr->p->sections, e) {
 326                         s = uci_to_section(e);
 327                         if (name && (strcmp(s->type, name) != 0))
 328                                 continue;
 329
 330                         c++;
 331                 }
 332                 idx += c;
 333         }
 334
 335         c = 0;
 336         uci_foreach_element(&ptr->p->sections, e) {
 337                 s = uci_to_section(e);
 338                 if (name && (strcmp(s->type, name) != 0))
 339                         continue;
 340
 341                 if (idx == c)
 342                         goto done;
 343                 c++;
 344         }
 345         e = NULL;
 346         goto done;
 347
 348 error:
 349         free(section);
 350         memset(ptr, 0, sizeof(struct uci_ptr));
 351         UCI_THROW(ctx, UCI_ERR_INVAL);
 352 done:
 353         free(section);
 354         if (e)
 355                 ptr->section = e->name;
 356         return e;
 357 }
 358
 359 int
 360 uci_lookup_next(struct uci_context *ctx, struct uci_element **e, struct uci_list *list, const char *name)
 361 {
 362         UCI_HANDLE_ERR(ctx);
 363
 364         *e = uci_lookup_list(list, name);
 365         if (!*e)
 366                 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 367
 368         return 0;
 369 }
 370
 371 int
 372 uci_lookup_ptr(struct uci_context *ctx, struct uci_ptr *ptr, char *str, bool extended)
 373 {
 374         struct uci_element *e;
 375
 376         UCI_HANDLE_ERR(ctx);
 377         UCI_ASSERT(ctx, ptr != NULL);
 378
 379         if (str)
 380                 UCI_INTERNAL(uci_parse_ptr, ctx, ptr, str);
 381
 382         ptr->flags |= UCI_LOOKUP_DONE;
 383
 384         /* look up the package first */
 385         if (ptr->p)
 386                 e = &ptr->p->e;
 387         else
 388                 e = uci_lookup_list(&ctx->root, ptr->package);
 389
 390         if (!e) {
 391                 UCI_INTERNAL(uci_load, ctx, ptr->package, &ptr->p);
 392                 if (!ptr->p)
 393                         goto notfound;
 394                 ptr->last = &ptr->p->e;
 395         } else {
 396                 ptr->p = uci_to_package(e);
 397                 ptr->last = e;
 398         }
 399
 400         if (!ptr->section && !ptr->s)
 401                 goto complete;
 402
 403         /* if the section name validates as a regular name, pass through
 404          * to the regular uci_lookup function call */
 405         if (ptr->s) {
 406                 e = &ptr->s->e;
 407         } else if (ptr->flags & UCI_LOOKUP_EXTENDED) {
 408                 if (extended)
 409                         e = uci_lookup_ext_section(ctx, ptr);
 410                 else
 411                         UCI_THROW(ctx, UCI_ERR_INVAL);
 412         } else {
 413                 e = uci_lookup_list(&ptr->p->sections, ptr->section);
 414         }
 415
 416         if (!e)
 417                 goto abort;
 418
 419         ptr->last = e;
 420         ptr->s = uci_to_section(e);
 421
 422         if (ptr->option) {
 423                 e = uci_lookup_list(&ptr->s->options, ptr->option);
 424                 if (!e)
 425                         goto abort;
 426
 427                 ptr->o = uci_to_option(e);
 428                 ptr->last = e;
 429         }
 430
 431 complete:
 432         ptr->flags |= UCI_LOOKUP_COMPLETE;
 433 abort:
 434         return UCI_OK;
 435
 436 notfound:
 437         UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 438         /* not a chance here */
 439         return UCI_ERR_NOTFOUND;
 440 }
 441
 442 __private struct uci_element *
 443 uci_expand_ptr(struct uci_context *ctx, struct uci_ptr *ptr, bool complete)
 444 {
 445         UCI_ASSERT(ctx, ptr != NULL);
 446
 447         if (!(ptr->flags & UCI_LOOKUP_DONE))
 448                 UCI_INTERNAL(uci_lookup_ptr, ctx, ptr, NULL, 1);
 449         if (complete && !(ptr->flags & UCI_LOOKUP_COMPLETE))
 450                 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 451         UCI_ASSERT(ctx, ptr->p != NULL);
 452
 453         /* fill in missing string info */
 454         if (ptr->p && !ptr->package)
 455                 ptr->package = ptr->p->e.name;
 456         if (ptr->s && !ptr->section)
 457                 ptr->section = ptr->s->e.name;
 458         if (ptr->o && !ptr->option)
 459                 ptr->option = ptr->o->e.name;
 460
 461         if (ptr->o)
 462                 return &ptr->o->e;
 463         if (ptr->s)
 464                 return &ptr->s->e;
 465         if (ptr->p)
 466                 return &ptr->p->e;
 467         else
 468                 return NULL;
 469 }
 470
 471 static void uci_add_element_list(struct uci_context *ctx, struct uci_ptr *ptr, bool internal)
 472 {
 473         struct uci_element *e;
 474         struct uci_package *p;
 475
 476         p = ptr->p;
 477         if (!internal && p->has_delta)
 478                 uci_add_delta(ctx, &p->delta, UCI_CMD_LIST_ADD, ptr->section, ptr->option, ptr->value);
 479
 480         e = uci_alloc_generic(ctx, UCI_TYPE_ITEM, ptr->value, sizeof(struct uci_option));
 481         uci_list_add(&ptr->o->v.list, &e->list);
 482 }
 483
 484 int uci_rename(struct uci_context *ctx, struct uci_ptr *ptr)
 485 {
 486         /* NB: UCI_INTERNAL use means without delta tracking */
 487         bool internal = ctx && ctx->internal;
 488         struct uci_element *e;
 489         struct uci_package *p;
 490         char *n;
 491
 492         UCI_HANDLE_ERR(ctx);
 493
 494         e = uci_expand_ptr(ctx, ptr, true);
 495         p = ptr->p;
 496
 497         UCI_ASSERT(ctx, ptr->s);
 498         UCI_ASSERT(ctx, ptr->value);
 499
 500         if (!internal && p->has_delta)
 501                 uci_add_delta(ctx, &p->delta, UCI_CMD_RENAME, ptr->section, ptr->option, ptr->value);
 502
 503         n = uci_strdup(ctx, ptr->value);
 504         free(e->name);
 505         e->name = n;
 506
 507         if (e->type == UCI_TYPE_SECTION)
 508                 uci_to_section(e)->anonymous = false;
 509
 510         return 0;
 511 }
 512
 513 int uci_reorder_section(struct uci_context *ctx, struct uci_section *s, int pos)
 514 {
 515         struct uci_package *p = s->package;
 516         bool internal = ctx && ctx->internal;
 517         char order[32];
 518
 519         UCI_HANDLE_ERR(ctx);
 520
 521         uci_list_set_pos(&s->package->sections, &s->e.list, pos);
 522         if (!internal && p->has_delta) {
 523                 sprintf(order, "%d", pos);
 524                 uci_add_delta(ctx, &p->delta, UCI_CMD_REORDER, s->e.name, NULL, order);
 525         }
 526
 527         return 0;
 528 }
 529
 530 int uci_add_section(struct uci_context *ctx, struct uci_package *p, const char *type, struct uci_section **res)
 531 {
 532         bool internal = ctx && ctx->internal;
 533         struct uci_section *s;
 534
 535         UCI_HANDLE_ERR(ctx);
 536         UCI_ASSERT(ctx, p != NULL);
 537         s = uci_alloc_section(p, type, NULL);
 538         if (s && s->anonymous)
 539                 uci_fixup_section(ctx, s);
 540         *res = s;
 541         if (!internal && p->has_delta)
 542                 uci_add_delta(ctx, &p->delta, UCI_CMD_ADD, s->e.name, NULL, type);
 543
 544         return 0;
 545 }
 546
 547 int uci_delete(struct uci_context *ctx, struct uci_ptr *ptr)
 548 {
 549         /* NB: pass on internal flag to uci_del_element */
 550         bool internal = ctx && ctx->internal;
 551         struct uci_package *p;
 552         struct uci_element *e1, *e2, *tmp;
 553         int index;
 554
 555         UCI_HANDLE_ERR(ctx);
 556
 557         e1 = uci_expand_ptr(ctx, ptr, true);
 558         p = ptr->p;
 559
 560         UCI_ASSERT(ctx, ptr->s);
 561
 562         if (ptr->o && ptr->o->type == UCI_TYPE_LIST && ptr->value && *ptr->value) {
 563                 if (!sscanf(ptr->value, "%d", &index))
 564                         return 1;
 565
 566                 uci_foreach_element_safe(&ptr->o->v.list, tmp, e2) {
 567                         if (index == 0) {
 568                                 if (!internal && p->has_delta)
 569                                         uci_add_delta(ctx, &p->delta, UCI_CMD_REMOVE, ptr->section, ptr->option, ptr->value);
 570                                 uci_free_option(uci_to_option(e2));
 571                                 return 0;
 572                         }
 573                         index--;
 574                 }
 575
 576                 return 0;
 577         }
 578
 579         if (!internal && p->has_delta)
 580                 uci_add_delta(ctx, &p->delta, UCI_CMD_REMOVE, ptr->section, ptr->option, NULL);
 581
 582         uci_free_any(&e1);
 583
 584         if (ptr->option)
 585                 ptr->o = NULL;
 586         else if (ptr->section)
 587                 ptr->s = NULL;
 588
 589         return 0;
 590 }
 591
 592 int uci_add_list(struct uci_context *ctx, struct uci_ptr *ptr)
 593 {
 594         /* NB: UCI_INTERNAL use means without delta tracking */
 595         bool internal = ctx && ctx->internal;
 596         struct uci_option *prev = NULL;
 597         const char *value2 = NULL;
 598
 599         UCI_HANDLE_ERR(ctx);
 600
 601         uci_expand_ptr(ctx, ptr, false);
 602         UCI_ASSERT(ctx, ptr->s);
 603         UCI_ASSERT(ctx, ptr->value);
 604
 605         if (ptr->o) {
 606                 switch (ptr->o->type) {
 607                 case UCI_TYPE_STRING:
 608                         /* we already have a string value, convert that to a list */
 609                         prev = ptr->o;
 610                         value2 = ptr->value;
 611                         ptr->value = ptr->o->v.string;
 612                         break;
 613                 case UCI_TYPE_LIST:
 614                         uci_add_element_list(ctx, ptr, internal);
 615                         return 0;
 616                 default:
 617                         UCI_THROW(ctx, UCI_ERR_INVAL);
 618                         break;
 619                 }
 620         }
 621
 622         ptr->o = uci_alloc_list(ptr->s, ptr->option);
 623         if (prev) {
 624                 uci_add_element_list(ctx, ptr, true);
 625                 uci_free_option(prev);
 626                 ptr->value = value2;
 627         }
 628         uci_add_element_list(ctx, ptr, internal);
 629
 630         return 0;
 631 }
 632
 633 int uci_del_list(struct uci_context *ctx, struct uci_ptr *ptr)
 634 {
 635         /* NB: pass on internal flag to uci_del_element */
 636         bool internal = ctx && ctx->internal;
 637         struct uci_element *e, *tmp;
 638         struct uci_package *p;
 639
 640         UCI_HANDLE_ERR(ctx);
 641
 642         uci_expand_ptr(ctx, ptr, false);
 643         UCI_ASSERT(ctx, ptr->s);
 644         UCI_ASSERT(ctx, ptr->value);
 645
 646         if (!(ptr->o && ptr->option))
 647                 return 0;
 648
 649         if ((ptr->o->type != UCI_TYPE_LIST))
 650                 return 0;
 651
 652         p = ptr->p;
 653         if (!internal && p->has_delta)
 654                 uci_add_delta(ctx, &p->delta, UCI_CMD_LIST_DEL, ptr->section, ptr->option, ptr->value);
 655
 656         uci_foreach_element_safe(&ptr->o->v.list, tmp, e) {
 657                 if (!strcmp(ptr->value, uci_to_option(e)->e.name)) {
 658                         uci_free_option(uci_to_option(e));
 659                 }
 660         }
 661
 662         return 0;
 663 }
 664
 665 int uci_set(struct uci_context *ctx, struct uci_ptr *ptr)
 666 {
 667         /* NB: UCI_INTERNAL use means without delta tracking */
 668         bool internal = ctx && ctx->internal;
 669
 670         UCI_HANDLE_ERR(ctx);
 671         uci_expand_ptr(ctx, ptr, false);
 672         UCI_ASSERT(ctx, ptr->value);
 673         UCI_ASSERT(ctx, ptr->s || (!ptr->option && ptr->section));
 674         if (!ptr->option && ptr->value[0]) {
 675                 UCI_ASSERT(ctx, uci_validate_type(ptr->value));
 676         }
 677
 678         if (!ptr->o && ptr->s && ptr->option) {
 679                 struct uci_element *e;
 680                 e = uci_lookup_list(&ptr->s->options, ptr->option);
 681                 if (e)
 682                         ptr->o = uci_to_option(e);
 683         }
 684         if (!ptr->value[0]) {
 685                 /* if setting a nonexistant option/section to a nonexistant value,
 686                  * exit without errors */
 687                 if (!(ptr->flags & UCI_LOOKUP_COMPLETE))
 688                         return 0;
 689
 690                 return uci_delete(ctx, ptr);
 691         } else if (!ptr->o && ptr->option) { /* new option */
 692                 ptr->o = uci_alloc_option(ptr->s, ptr->option, ptr->value);
 693                 ptr->last = &ptr->o->e;
 694         } else if (!ptr->s && ptr->section) { /* new section */
 695                 ptr->s = uci_alloc_section(ptr->p, ptr->value, ptr->section);
 696                 ptr->last = &ptr->s->e;
 697         } else if (ptr->o && ptr->option) { /* update option */
 698                 if ((ptr->o->type == UCI_TYPE_STRING) &&
 699                         !strcmp(ptr->o->v.string, ptr->value))
 700                         return 0;
 701                 uci_free_option(ptr->o);
 702                 ptr->o = uci_alloc_option(ptr->s, ptr->option, ptr->value);
 703                 ptr->last = &ptr->o->e;
 704         } else if (ptr->s && ptr->section) { /* update section */
 705                 char *s = uci_strdup(ctx, ptr->value);
 706
 707                 if (ptr->s->type == uci_dataptr(ptr->s)) {
 708                         ptr->last = NULL;
 709                         ptr->last = uci_realloc(ctx, ptr->s, sizeof(struct uci_section));
 710                         ptr->s = uci_to_section(ptr->last);
 711                         uci_list_fixup(&ptr->s->e.list);
 712                 } else {
 713                         free(ptr->s->type);
 714                 }
 715                 ptr->s->type = s;
 716         } else {
 717                 UCI_THROW(ctx, UCI_ERR_INVAL);
 718         }
 719
 720         if (!internal && ptr->p->has_delta)
 721                 uci_add_delta(ctx, &ptr->p->delta, UCI_CMD_CHANGE, ptr->section, ptr->option, ptr->value);
 722
 723         return 0;
 724 }
 725
 726 int uci_unload(struct uci_context *ctx, struct uci_package *p)
 727 {
 728         UCI_HANDLE_ERR(ctx);
 729         UCI_ASSERT(ctx, p != NULL);
 730
 731         uci_free_package(&p);
 732         return 0;
 733 }
 734