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         }
 222
 223         *res = e;
 224         return 0;
 225
 226 notfound:
 227         UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 228         return 0;
 229 }
 230
 231 int uci_del_element(struct uci_context *ctx, struct uci_element *e)
 232 {
 233         /* NB: UCI_INTERNAL use means without history tracking */
 234         bool internal = ctx->internal;
 235         struct uci_package *p = NULL;
 236         struct uci_section *s = NULL;
 237         struct uci_option *o = NULL;
 238         struct uci_element *i, *tmp;
 239         char *option = NULL;
 240
 241         UCI_HANDLE_ERR(ctx);
 242         UCI_ASSERT(ctx, e != NULL);
 243
 244         switch(e->type) {
 245         case UCI_TYPE_SECTION:
 246                 s = uci_to_section(e);
 247                 uci_foreach_element_safe(&s->options, tmp, i) {
 248                         uci_del_element(ctx, i);
 249                 }
 250                 break;
 251         case UCI_TYPE_OPTION:
 252                 o = uci_to_option(e);
 253                 s = o->section;
 254                 p = s->package;
 255                 option = e->name;
 256                 break;
 257         default:
 258                 UCI_THROW(ctx, UCI_ERR_INVAL);
 259                 break;
 260         }
 261
 262         p = s->package;
 263         if (!internal && p->confdir)
 264                 uci_add_history(ctx, &p->history, UCI_CMD_REMOVE, s->e.name, option, NULL);
 265
 266         switch(e->type) {
 267         case UCI_TYPE_SECTION:
 268                 uci_free_section(s);
 269                 break;
 270         case UCI_TYPE_OPTION:
 271                 uci_free_option(o);
 272                 break;
 273         default:
 274                 break;
 275         }
 276         return 0;
 277 }
 278
 279 int uci_set_element_value(struct uci_context *ctx, struct uci_element **element, char *value)
 280 {
 281         /* NB: UCI_INTERNAL use means without history tracking */
 282         bool internal = ctx->internal;
 283         struct uci_list *list;
 284         struct uci_element *e;
 285         struct uci_package *p;
 286         struct uci_section *s;
 287         char *section;
 288         char *option;
 289         char *str;
 290         int size;
 291
 292         UCI_HANDLE_ERR(ctx);
 293         UCI_ASSERT(ctx, (element != NULL) && (*element != NULL));
 294
 295         /* what the 'value' of an element means depends on the type
 296          * for a section, the 'value' means its type
 297          * for an option, the 'value' means its value string
 298          * when changing the value, shrink the element to its actual size
 299          * (it may have been allocated with a bigger size, to include
 300          *  its buffer)
 301          * then duplicate the string passed on the command line and
 302          * insert it into the structure.
 303          */
 304         e = *element;
 305         list = e->list.prev;
 306         switch(e->type) {
 307         case UCI_TYPE_SECTION:
 308                 UCI_ASSERT(ctx, uci_validate_str(value, false));
 309                 size = sizeof(struct uci_section);
 310                 s = uci_to_section(e);
 311                 section = e->name;
 312                 option = NULL;
 313                 break;
 314         case UCI_TYPE_OPTION:
 315                 UCI_ASSERT(ctx, value != NULL);
 316                 size = sizeof(struct uci_option);
 317                 s = uci_to_option(e)->section;
 318                 section = s->e.name;
 319                 option = e->name;
 320                 break;
 321         default:
 322                 UCI_THROW(ctx, UCI_ERR_INVAL);
 323                 return 0;
 324         }
 325         p = s->package;
 326         if (!internal && p->confdir)
 327                 uci_add_history(ctx, &p->history, UCI_CMD_CHANGE, section, option, value);
 328
 329         uci_list_del(&e->list);
 330         e = uci_realloc(ctx, e, size);
 331         str = uci_strdup(ctx, value);
 332         uci_list_insert(list, &e->list);
 333         *element = e;
 334
 335         switch(e->type) {
 336         case UCI_TYPE_SECTION:
 337                 uci_to_section(e)->type = str;
 338                 break;
 339         case UCI_TYPE_OPTION:
 340                 uci_to_option(e)->value = str;
 341                 break;
 342         default:
 343                 break;
 344         }
 345
 346         return 0;
 347 }
 348
 349 int uci_rename(struct uci_context *ctx, struct uci_package *p, char *section, char *option, char *name)
 350 {
 351         /* NB: UCI_INTERNAL use means without history tracking */
 352         bool internal = ctx->internal;
 353         struct uci_element *e;
 354
 355         UCI_HANDLE_ERR(ctx);
 356
 357         /* NB: p, section, option validated by uci_lookup */
 358         UCI_INTERNAL(uci_lookup, ctx, &e, p, section, option);
 359
 360         if (!internal && p->confdir)
 361                 uci_add_history(ctx, &p->history, UCI_CMD_RENAME, section, option, name);
 362
 363         name = uci_strdup(ctx, name);
 364         if (e->name)
 365                 free(e->name);
 366         e->name = name;
 367
 368         return 0;
 369 }
 370
 371
 372 int uci_delete(struct uci_context *ctx, struct uci_package *p, char *section, char *option)
 373 {
 374         /* NB: pass on internal flag to uci_del_element */
 375         bool internal = ctx->internal;
 376         struct uci_element *e;
 377
 378         UCI_HANDLE_ERR(ctx);
 379
 380         /* NB: p, section, option validated by uci_lookup */
 381         UCI_INTERNAL(uci_lookup, ctx, &e, p, section, option);
 382
 383         ctx->internal = internal;
 384         return uci_del_element(ctx, e);
 385 }
 386
 387 int uci_set(struct uci_context *ctx, struct uci_package *p, char *section, char *option, char *value)
 388 {
 389         /* NB: UCI_INTERNAL use means without history tracking */
 390         bool internal = ctx->internal;
 391         struct uci_element *e = NULL;
 392         struct uci_section *s = NULL;
 393         struct uci_option *o = NULL;
 394
 395         UCI_HANDLE_ERR(ctx);
 396         UCI_ASSERT(ctx, p != NULL);
 397         UCI_ASSERT(ctx, uci_validate_name(section));
 398         if (option) {
 399                 UCI_ASSERT(ctx, uci_validate_name(option));
 400                 UCI_ASSERT(ctx, value != NULL);
 401         } else {
 402                 UCI_ASSERT(ctx, uci_validate_str(value, false));
 403         }
 404
 405         /*
 406          * look up the package, section and option (if set)
 407          * if the section/option is to be modified and it is not found
 408          * create a new element in the appropriate list
 409          */
 410         e = uci_lookup_list(ctx, &p->sections, section);
 411         if (!e)
 412                 goto notfound;
 413
 414         s = uci_to_section(e);
 415         if (ctx->pctx && ctx->pctx->merge)
 416                 ctx->pctx->section = s;
 417
 418         if (option) {
 419                 e = uci_lookup_list(ctx, &s->options, option);
 420                 if (!e)
 421                         goto notfound;
 422                 o = uci_to_option(e);
 423         }
 424
 425         /*
 426          * no unknown element was supplied, assume that we can just update
 427          * an existing entry
 428          */
 429         if (o)
 430                 e = &o->e;
 431         else
 432                 e = &s->e;
 433
 434         ctx->internal = internal;
 435         return uci_set_element_value(ctx, &e, value);
 436
 437 notfound:
 438         /*
 439          * the entry that we need to update was not found,
 440          * check if the search failed prematurely.
 441          * this can happen if the package was not found, or if
 442          * an option was supplied, but the section wasn't found
 443          */
 444         if (!p || (!s && option))
 445                 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
 446
 447         /* now add the missing entry */
 448         if (!internal && p->confdir)
 449                 uci_add_history(ctx, &p->history, UCI_CMD_ADD, section, option, value);
 450         if (s)
 451                 uci_alloc_option(s, option, value);
 452         else {
 453                 s = uci_alloc_section(p, value, section);
 454                 if (ctx->pctx && ctx->pctx->merge)
 455                         ctx->pctx->section = s;
 456         }
 457
 458         return 0;
 459 }
 460
 461 int uci_unload(struct uci_context *ctx, struct uci_package *p)
 462 {
 463         UCI_HANDLE_ERR(ctx);
 464         UCI_ASSERT(ctx, p != NULL);
 465
 466         uci_free_package(&p);
 467         return 0;
 468 }
 469