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 #include <glob.h>
  16
  17 /* initialize a list head/item */
  18 static inline void uci_list_init(struct uci_list *ptr)
  19 {
  20         ptr->prev = ptr;
  21         ptr->next = ptr;
  22 }
  23
  24 /* inserts a new list entry after a given entry */
  25 static inline void uci_list_insert(struct uci_list *list, struct uci_list *ptr)
  26 {
  27         list->next->prev = ptr;
  28         ptr->prev = list;
  29         ptr->next = list->next;
  30         list->next = ptr;
  31 }
  32
  33 /* inserts a new list entry at the tail of the list */
  34 static inline void uci_list_add(struct uci_list *head, struct uci_list *ptr)
  35 {
  36         /* NB: head->prev points at the tail */
  37         uci_list_insert(head->prev, ptr);
  38 }
  39
  40 static inline void uci_list_del(struct uci_list *ptr)
  41 {
  42         struct uci_list *next, *prev;
  43
  44         next = ptr->next;
  45         prev = ptr->prev;
  46
  47         prev->next = next;
  48         next->prev = prev;
  49
  50         uci_list_init(ptr);
  51 }
  52
  53 /*
  54  * uci_alloc_generic allocates a new uci_element with payload
  55  * payload is appended to the struct to save memory and reduce fragmentation
  56  */
  57 static struct uci_element *
  58 uci_alloc_generic(struct uci_context *ctx, int type, const char *name, int size)
  59 {
  60         struct uci_element *e;
  61         int datalen = size;
  62         void *ptr;
  63
  64         ptr = uci_malloc(ctx, datalen);
  65         e = (struct uci_element *) ptr;
  66         e->type = type;
  67         if (name) {
  68                 UCI_TRAP_SAVE(ctx, error);
  69                 e->name = uci_strdup(ctx, name);
  70                 UCI_TRAP_RESTORE(ctx);
  71         }
  72         uci_list_init(&e->list);
  73         goto done;
  74
  75 error:
  76         free(ptr);
  77         UCI_THROW(ctx, ctx->errno);
  78
  79 done:
  80         return e;
  81 }
  82
  83 static void
  84 uci_free_element(struct uci_element *e)
  85 {
  86         if (e->name)
  87                 free(e->name);
  88         if (!uci_list_empty(&e->list))
  89                 uci_list_del(&e->list);
  90         free(e);
  91 }
  92
  93 static struct uci_option *
  94 uci_alloc_option(struct uci_section *s, const char *name, const char *value)
  95 {
  96         struct uci_package *p = s->package;
  97         struct uci_context *ctx = p->ctx;
  98         struct uci_option *o;
  99
 100         o = uci_alloc_element(ctx, option, name, strlen(value) + 1);
 101         o->value = uci_dataptr(o);
 102         o->section = s;
 103         strcpy(o->value, value);
 104         uci_list_add(&s->options, &o->e.list);
 105
 106         return o;
 107 }
 108
 109 static inline void
 110 uci_free_option(struct uci_option *o)
 111 {
 112         if ((o->value != uci_dataptr(o)) &&
 113                 (o->value != NULL))
 114                 free(o->value);
 115         uci_free_element(&o->e);
 116 }
 117
 118 static struct uci_section *
 119 uci_alloc_section(struct uci_package *p, const char *type, const char *name)
 120 {
 121         struct uci_context *ctx = p->ctx;
 122         struct uci_section *s;
 123
 124         if (name && !name[0])
 125                 name = NULL;
 126
 127         s = uci_alloc_element(ctx, section, name, strlen(type) + 1);
 128         uci_list_init(&s->options);
 129         s->type = uci_dataptr(s);
 130         s->package = p;
 131         strcpy(s->type, type);
 132         if (name == NULL)
 133                 s->anonymous = true;
 134
 135         uci_list_add(&p->sections, &s->e.list);
 136
 137         return s;
 138 }
 139
 140 static void
 141 uci_free_section(struct uci_section *s)
 142 {
 143         struct uci_element *o, *tmp;
 144
 145         uci_foreach_element_safe(&s->options, tmp, o) {
 146                 uci_free_option(uci_to_option(o));
 147         }
 148         if ((s->type != uci_dataptr(s)) &&
 149                 (s->type != NULL))
 150                 free(s->type);
 151         uci_free_element(&s->e);
 152 }
 153
 154 static struct uci_package *
 155 uci_alloc_package(struct uci_context *ctx, const char *name)
 156 {
 157         struct uci_package *p;
 158
 159         p = uci_alloc_element(ctx, package, name, 0);
 160         p->ctx = ctx;
 161         uci_list_init(&p->sections);
 162         uci_list_init(&p->history);
 163         uci_list_init(&p->saved_history);
 164         return p;
 165 }
 166
 167 static void
 168 uci_free_package(struct uci_package **package)
 169 {
 170         struct uci_element *e, *tmp;
 171         struct uci_package *p = *package;
 172
 173         if(!p)
 174                 return;
 175
 176         if (p->path)
 177                 free(p->path);
 178         uci_foreach_element_safe(&p->sections, tmp, e) {
 179                 uci_free_section(uci_to_section(e));
 180         }
 181         uci_foreach_element_safe(&p->history, tmp, e) {
 182                 uci_free_history(uci_to_history(e));
 183         }
 184         uci_foreach_element_safe(&p->saved_history, tmp, e) {
 185                 uci_free_history(uci_to_history(e));
 186         }
 187         uci_free_element(&p->e);
 188         *package = NULL;
 189 }
 190
 191 static struct uci_element *uci_lookup_list(struct uci_context *ctx, struct uci_list *list, const char *name)
 192 {
 193         struct uci_element *e;
 194
 195         uci_foreach_element(list, e) {
 196                 if (!strcmp(e->name, name))
 197                         return e;
 198         }
 199         return NULL;
 200 }
 201
 202 int uci_lookup(struct uci_context *ctx, struct uci_element **res, struct uci_package *p, char *section, char *option)
 203 {
 204         struct uci_element *e;
 205         struct uci_section *s;
 206
 207         UCI_HANDLE_ERR(ctx);
 208         UCI_ASSERT(ctx, res != NULL);
 209         UCI_ASSERT(ctx, p != NULL);
 210         UCI_ASSERT(ctx, uci_validate_name(section));
 211         if (option)
 212                 UCI_ASSERT(ctx, uci_validate_name(option));
 213
 214         e = uci_lookup_list(ctx, &p->sections, section);
 215         if (!e)
 216                 goto notfound;
 217
 218         if (option) {
 219                 s = uci_to_section(e);
 220                 e = uci_lookup_list(ctx, &s->options, option);
 221                 if (!e)
 222                         goto notfound;
 223         }
 224
 225         *res = e;
 226         return 0;
 227
 228 notfound:
 229         UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 230         return 0;
 231 }
 232
 233 int uci_del_element(struct uci_context *ctx, struct uci_element *e)
 234 {
 235         /* NB: UCI_INTERNAL use means without history tracking */
 236         bool internal = ctx->internal;
 237         struct uci_package *p = NULL;
 238         struct uci_section *s = NULL;
 239         struct uci_option *o = NULL;
 240         struct uci_element *i, *tmp;
 241         char *option = NULL;
 242
 243         UCI_HANDLE_ERR(ctx);
 244         UCI_ASSERT(ctx, e != NULL);
 245
 246         switch(e->type) {
 247         case UCI_TYPE_SECTION:
 248                 s = uci_to_section(e);
 249                 uci_foreach_element_safe(&s->options, tmp, i) {
 250                         uci_del_element(ctx, i);
 251                 }
 252                 break;
 253         case UCI_TYPE_OPTION:
 254                 o = uci_to_option(e);
 255                 s = o->section;
 256                 p = s->package;
 257                 option = e->name;
 258                 break;
 259         default:
 260                 UCI_THROW(ctx, UCI_ERR_INVAL);
 261                 break;
 262         }
 263
 264         p = s->package;
 265         if (!internal && p->confdir)
 266                 uci_add_history(ctx, &p->history, UCI_CMD_REMOVE, s->e.name, option, NULL);
 267
 268         switch(e->type) {
 269         case UCI_TYPE_SECTION:
 270                 uci_free_section(s);
 271                 break;
 272         case UCI_TYPE_OPTION:
 273                 uci_free_option(o);
 274                 break;
 275         default:
 276                 break;
 277         }
 278         return 0;
 279 }
 280
 281 int uci_set_element_value(struct uci_context *ctx, struct uci_element **element, char *value)
 282 {
 283         /* NB: UCI_INTERNAL use means without history tracking */
 284         bool internal = ctx->internal;
 285         struct uci_list *list;
 286         struct uci_element *e;
 287         struct uci_package *p;
 288         struct uci_section *s;
 289         char *section;
 290         char *option;
 291         char *str;
 292         int size;
 293
 294         UCI_HANDLE_ERR(ctx);
 295         UCI_ASSERT(ctx, (element != NULL) && (*element != NULL));
 296
 297         /* what the 'value' of an element means depends on the type
 298          * for a section, the 'value' means its type
 299          * for an option, the 'value' means its value string
 300          * when changing the value, shrink the element to its actual size
 301          * (it may have been allocated with a bigger size, to include
 302          *  its buffer)
 303          * then duplicate the string passed on the command line and
 304          * insert it into the structure.
 305          */
 306         e = *element;
 307         list = e->list.prev;
 308         switch(e->type) {
 309         case UCI_TYPE_SECTION:
 310                 UCI_ASSERT(ctx, uci_validate_str(value, false));
 311                 size = sizeof(struct uci_section);
 312                 s = uci_to_section(e);
 313                 section = e->name;
 314                 option = NULL;
 315                 break;
 316         case UCI_TYPE_OPTION:
 317                 UCI_ASSERT(ctx, value != NULL);
 318                 size = sizeof(struct uci_option);
 319                 s = uci_to_option(e)->section;
 320                 section = s->e.name;
 321                 option = e->name;
 322                 break;
 323         default:
 324                 UCI_THROW(ctx, UCI_ERR_INVAL);
 325                 return 0;
 326         }
 327         p = s->package;
 328         if (!internal && p->confdir)
 329                 uci_add_history(ctx, &p->history, UCI_CMD_CHANGE, section, option, value);
 330
 331         uci_list_del(&e->list);
 332         e = uci_realloc(ctx, e, size);
 333         str = uci_strdup(ctx, value);
 334         uci_list_insert(list, &e->list);
 335         *element = e;
 336
 337         switch(e->type) {
 338         case UCI_TYPE_SECTION:
 339                 uci_to_section(e)->type = str;
 340                 break;
 341         case UCI_TYPE_OPTION:
 342                 uci_to_option(e)->value = str;
 343                 break;
 344         default:
 345                 break;
 346         }
 347
 348         return 0;
 349 }
 350
 351 int uci_rename(struct uci_context *ctx, struct uci_package *p, char *section, char *option, char *name)
 352 {
 353         /* NB: UCI_INTERNAL use means without history tracking */
 354         bool internal = ctx->internal;
 355         struct uci_element *e;
 356
 357         UCI_HANDLE_ERR(ctx);
 358
 359         /* NB: p, section, option validated by uci_lookup */
 360         UCI_INTERNAL(uci_lookup, ctx, &e, p, section, option);
 361
 362         if (!internal && p->confdir)
 363                 uci_add_history(ctx, &p->history, UCI_CMD_RENAME, section, option, name);
 364
 365         name = uci_strdup(ctx, name);
 366         if (e->name)
 367                 free(e->name);
 368         e->name = name;
 369
 370         return 0;
 371 }
 372
 373
 374 int uci_delete(struct uci_context *ctx, struct uci_package *p, char *section, char *option)
 375 {
 376         /* NB: pass on internal flag to uci_del_element */
 377         bool internal = ctx->internal;
 378         struct uci_element *e;
 379
 380         UCI_HANDLE_ERR(ctx);
 381
 382         /* NB: p, section, option validated by uci_lookup */
 383         UCI_INTERNAL(uci_lookup, ctx, &e, p, section, option);
 384
 385         ctx->internal = internal;
 386         return uci_del_element(ctx, e);
 387 }
 388
 389 int uci_set(struct uci_context *ctx, struct uci_package *p, char *section, char *option, char *value, struct uci_element **result)
 390 {
 391         /* NB: UCI_INTERNAL use means without history tracking */
 392         bool internal = ctx->internal;
 393         struct uci_element *e = NULL;
 394         struct uci_section *s = NULL;
 395         struct uci_option *o = NULL;
 396
 397         UCI_HANDLE_ERR(ctx);
 398         UCI_ASSERT(ctx, p != NULL);
 399         UCI_ASSERT(ctx, uci_validate_name(section));
 400         if (option) {
 401                 UCI_ASSERT(ctx, uci_validate_name(option));
 402                 UCI_ASSERT(ctx, value != NULL);
 403         } else {
 404                 UCI_ASSERT(ctx, uci_validate_str(value, false));
 405         }
 406
 407         /*
 408          * look up the package, section and option (if set)
 409          * if the section/option is to be modified and it is not found
 410          * create a new element in the appropriate list
 411          */
 412         e = uci_lookup_list(ctx, &p->sections, section);
 413         if (!e)
 414                 goto notfound;
 415
 416         s = uci_to_section(e);
 417         if (ctx->pctx && ctx->pctx->merge)
 418                 ctx->pctx->section = s;
 419
 420         if (option) {
 421                 e = uci_lookup_list(ctx, &s->options, option);
 422                 if (!e)
 423                         goto notfound;
 424                 o = uci_to_option(e);
 425         }
 426
 427         /*
 428          * no unknown element was supplied, assume that we can just update
 429          * an existing entry
 430          */
 431         if (o)
 432                 e = &o->e;
 433         else
 434                 e = &s->e;
 435         if (result)
 436                 *result = e;
 437         else
 438                 result = &e;
 439
 440         ctx->internal = internal;
 441         return uci_set_element_value(ctx, result, value);
 442
 443 notfound:
 444         /*
 445          * the entry that we need to update was not found,
 446          * check if the search failed prematurely.
 447          * this can happen if the package was not found, or if
 448          * an option was supplied, but the section wasn't found
 449          */
 450         if (!p || (!s && option))
 451                 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 452
 453         /* now add the missing entry */
 454         if (!internal && p->confdir)
 455                 uci_add_history(ctx, &p->history, UCI_CMD_ADD, section, option, value);
 456         if (s) {
 457                 o = uci_alloc_option(s, option, value);
 458                 if (result)
 459                         *result = &o->e;
 460         } else {
 461                 s = uci_alloc_section(p, value, section);
 462                 if (result)
 463                         *result = &s->e;
 464                 if (ctx->pctx && ctx->pctx->merge)
 465                         ctx->pctx->section = s;
 466         }
 467
 468         return 0;
 469 }
 470
 471 int uci_unload(struct uci_context *ctx, struct uci_package *p)
 472 {
 473         UCI_HANDLE_ERR(ctx);
 474         UCI_ASSERT(ctx, p != NULL);
 475
 476         uci_free_package(&p);
 477         return 0;
 478 }
 479