0924edfc173df808404a98fad148c43905611b21
[project/uci.git] / 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->err);
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->type = UCI_TYPE_STRING;
102 o->v.string = uci_dataptr(o);
103 o->section = s;
104 strcpy(o->v.string, value);
105 uci_list_add(&s->options, &o->e.list);
106
107 return o;
108 }
109
110 static inline void
111 uci_free_option(struct uci_option *o)
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 default:
120 break;
121 }
122 uci_free_element(&o->e);
123 }
124
125 /* fix up an unnamed section, e.g. after adding options to it */
126 static void uci_fixup_section(struct uci_context *ctx, struct uci_section *s)
127 {
128 unsigned int hash = ~0;
129 struct uci_element *e;
130 char buf[16];
131
132 if (!s || s->e.name)
133 return;
134
135 /*
136 * Generate a name for unnamed sections. This is used as reference
137 * when locating or updating the section from apps/scripts.
138 * To make multiple concurrent versions somewhat safe for updating,
139 * the name is generated from a hash of its type and name/value
140 * pairs of its option, and it is prefixed by a counter value.
141 * If the order of the unnamed sections changes for some reason,
142 * updates to them will be rejected.
143 */
144 hash = djbhash(hash, s->type);
145 uci_foreach_element(&s->options, e) {
146 struct uci_option *o;
147 hash = djbhash(hash, e->name);
148 o = uci_to_option(e);
149 switch(o->type) {
150 case UCI_TYPE_STRING:
151 hash = djbhash(hash, o->v.string);
152 break;
153 default:
154 break;
155 }
156 }
157 sprintf(buf, "cfg%02x%04x", ++s->package->n_section, hash % (1 << 16));
158 s->e.name = uci_strdup(ctx, buf);
159 }
160
161 static struct uci_section *
162 uci_alloc_section(struct uci_package *p, const char *type, const char *name)
163 {
164 struct uci_context *ctx = p->ctx;
165 struct uci_section *s;
166
167 if (name && !name[0])
168 name = NULL;
169
170 s = uci_alloc_element(ctx, section, name, strlen(type) + 1);
171 uci_list_init(&s->options);
172 s->type = uci_dataptr(s);
173 s->package = p;
174 strcpy(s->type, type);
175 if (name == NULL)
176 s->anonymous = true;
177 p->n_section++;
178
179 uci_list_add(&p->sections, &s->e.list);
180
181 return s;
182 }
183
184 static void
185 uci_free_section(struct uci_section *s)
186 {
187 struct uci_element *o, *tmp;
188
189 uci_foreach_element_safe(&s->options, tmp, o) {
190 uci_free_option(uci_to_option(o));
191 }
192 if ((s->type != uci_dataptr(s)) &&
193 (s->type != NULL))
194 free(s->type);
195 uci_free_element(&s->e);
196 }
197
198 __plugin struct uci_package *
199 uci_alloc_package(struct uci_context *ctx, const char *name)
200 {
201 struct uci_package *p;
202
203 p = uci_alloc_element(ctx, package, name, 0);
204 p->ctx = ctx;
205 uci_list_init(&p->sections);
206 uci_list_init(&p->history);
207 uci_list_init(&p->saved_history);
208 return p;
209 }
210
211 static void
212 uci_free_package(struct uci_package **package)
213 {
214 struct uci_element *e, *tmp;
215 struct uci_package *p = *package;
216
217 if(!p)
218 return;
219
220 if (p->path)
221 free(p->path);
222 uci_foreach_element_safe(&p->sections, tmp, e) {
223 uci_free_section(uci_to_section(e));
224 }
225 uci_foreach_element_safe(&p->history, tmp, e) {
226 uci_free_history(uci_to_history(e));
227 }
228 uci_foreach_element_safe(&p->saved_history, tmp, e) {
229 uci_free_history(uci_to_history(e));
230 }
231 uci_free_element(&p->e);
232 *package = NULL;
233 }
234
235 static struct uci_element *uci_lookup_list(struct uci_list *list, const char *name)
236 {
237 struct uci_element *e;
238
239 uci_foreach_element(list, e) {
240 if (!strcmp(e->name, name))
241 return e;
242 }
243 return NULL;
244 }
245
246 int uci_lookup_ext(struct uci_context *ctx, struct uci_element **res, char *ptr)
247 {
248 struct uci_package *p = NULL;
249 struct uci_element *e;
250 struct uci_section *s;
251 char *package = NULL;
252 char *section = NULL;
253 char *option = NULL;
254 char *idxstr, *t;
255 int idx, c;
256
257 UCI_HANDLE_ERR(ctx);
258 UCI_ASSERT(ctx, res != NULL);
259 UCI_ASSERT(ctx, ptr != NULL);
260
261 UCI_INTERNAL(uci_parse_tuple, ctx, ptr, &package, &section, &option, NULL);
262
263 /* look up the package first */
264 e = uci_lookup_list(&ctx->root, package);
265 if (!e) {
266 UCI_INTERNAL(uci_load, ctx, package, &p);
267 if (!p)
268 goto notfound;
269 e = &p->e;
270 } else {
271 p = uci_to_package(e);
272 }
273
274 if (!section)
275 goto done;
276
277 /* if the section name validates as a regular name, pass through
278 * to the regular uci_lookup function call */
279 if (!*section || uci_validate_name(section)) {
280 UCI_INTERNAL(uci_lookup, ctx, &e, p, section, option);
281 goto done;
282 }
283
284 /* name did not validate, that means we have an extended lookup call
285 * parse it here. for now only the section index syntax is supported */
286 if (section[0] != '@')
287 goto error;
288
289 section++;
290
291 /* parse the section index part */
292 idxstr = strchr(section, '[');
293 if (!idxstr)
294 goto error;
295 *idxstr = 0;
296 idxstr++;
297
298 t = strchr(idxstr, ']');
299 if (!t)
300 goto error;
301 if (t[1] != 0)
302 goto error;
303 *t = 0;
304
305 t = NULL;
306 idx = strtol(idxstr, &t, 10);
307 if (t && *t)
308 goto error;
309
310 if (!*section)
311 section = NULL;
312 if (section && !uci_validate_str(section, false))
313 goto error;
314
315 /* if the given index is negative, it specifies the section number from
316 * the end of the list */
317 if (idx < 0) {
318 c = 0;
319 uci_foreach_element(&p->sections, e) {
320 s = uci_to_section(e);
321 if (section && (strcmp(s->type, section) != 0))
322 continue;
323
324 c++;
325 }
326 idx += c;
327 }
328
329 c = 0;
330 uci_foreach_element(&p->sections, e) {
331 s = uci_to_section(e);
332 if (section && (strcmp(s->type, section) != 0))
333 continue;
334
335 if (idx == c)
336 goto found;
337 c++;
338 }
339 goto notfound;
340
341 found:
342 if (option)
343 e = uci_lookup_list(&s->options, option);
344 done:
345 *res = e;
346 return 0;
347
348 notfound:
349 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
350 error:
351 UCI_THROW(ctx, UCI_ERR_INVAL);
352 return 0;
353 }
354
355 int uci_lookup(struct uci_context *ctx, struct uci_element **res, struct uci_package *p, const char *section, const char *option)
356 {
357 struct uci_element *e;
358 struct uci_section *s;
359
360 UCI_HANDLE_ERR(ctx);
361 UCI_ASSERT(ctx, res != NULL);
362 UCI_ASSERT(ctx, p != NULL);
363 UCI_ASSERT(ctx, section && uci_validate_name(section));
364 if (option)
365 UCI_ASSERT(ctx, uci_validate_name(option));
366
367 e = uci_lookup_list(&p->sections, section);
368 if (!e)
369 goto notfound;
370
371 if (option) {
372 s = uci_to_section(e);
373 e = uci_lookup_list(&s->options, option);
374 if (!e)
375 goto notfound;
376 }
377
378 *res = e;
379 return 0;
380
381 notfound:
382 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
383 return 0;
384 }
385
386 int uci_del_element(struct uci_context *ctx, struct uci_element *e)
387 {
388 /* NB: UCI_INTERNAL use means without history tracking */
389 bool internal = ctx->internal;
390 struct uci_package *p = NULL;
391 struct uci_section *s = NULL;
392 struct uci_option *o = NULL;
393 struct uci_element *i, *tmp;
394 char *option = NULL;
395
396 UCI_HANDLE_ERR(ctx);
397 UCI_ASSERT(ctx, e != NULL);
398
399 switch(e->type) {
400 case UCI_TYPE_SECTION:
401 s = uci_to_section(e);
402 uci_foreach_element_safe(&s->options, tmp, i) {
403 uci_del_element(ctx, i);
404 }
405 break;
406 case UCI_TYPE_OPTION:
407 o = uci_to_option(e);
408 s = o->section;
409 p = s->package;
410 option = e->name;
411 break;
412 default:
413 UCI_THROW(ctx, UCI_ERR_INVAL);
414 break;
415 }
416
417 p = s->package;
418 if (!internal && p->has_history)
419 uci_add_history(ctx, &p->history, UCI_CMD_REMOVE, s->e.name, option, NULL);
420
421 switch(e->type) {
422 case UCI_TYPE_SECTION:
423 uci_free_section(s);
424 break;
425 case UCI_TYPE_OPTION:
426 uci_free_option(o);
427 break;
428 default:
429 break;
430 }
431 return 0;
432 }
433
434 int uci_set_element_value(struct uci_context *ctx, struct uci_element **element, const char *value)
435 {
436 /* NB: UCI_INTERNAL use means without history tracking */
437 bool internal = ctx->internal;
438 struct uci_list *list;
439 struct uci_element *e;
440 struct uci_package *p;
441 struct uci_section *s;
442 struct uci_option *o;
443 char *section;
444 char *option;
445 char *str;
446 int size;
447
448 UCI_HANDLE_ERR(ctx);
449 UCI_ASSERT(ctx, (element != NULL) && (*element != NULL));
450
451 /* what the 'value' of an element means depends on the type
452 * for a section, the 'value' means its type
453 * for an option, the 'value' means its value string
454 * when changing the value, shrink the element to its actual size
455 * (it may have been allocated with a bigger size, to include
456 * its buffer)
457 * then duplicate the string passed on the command line and
458 * insert it into the structure.
459 */
460 e = *element;
461 list = e->list.prev;
462 switch(e->type) {
463 case UCI_TYPE_SECTION:
464 UCI_ASSERT(ctx, uci_validate_str(value, false));
465 size = sizeof(struct uci_section);
466 s = uci_to_section(e);
467 section = e->name;
468 option = NULL;
469 /* matches the currently set value */
470 if (!strcmp(value, s->type))
471 return 0;
472 break;
473 case UCI_TYPE_OPTION:
474 UCI_ASSERT(ctx, value != NULL);
475 size = sizeof(struct uci_option);
476 o = uci_to_option(e);
477 s = o->section;
478 section = s->e.name;
479 option = o->e.name;
480 if (o->type != UCI_TYPE_STRING)
481 UCI_THROW(ctx, UCI_ERR_INVAL);
482 /* matches the currently set value */
483 if (!strcmp(value, o->v.string))
484 return 0;
485 break;
486 default:
487 UCI_THROW(ctx, UCI_ERR_INVAL);
488 return 0;
489 }
490 p = s->package;
491 if (!internal && p->has_history)
492 uci_add_history(ctx, &p->history, UCI_CMD_CHANGE, section, option, value);
493
494 uci_list_del(&e->list);
495 e = uci_realloc(ctx, e, size);
496 str = uci_strdup(ctx, value);
497 uci_list_insert(list, &e->list);
498 *element = e;
499
500 switch(e->type) {
501 case UCI_TYPE_SECTION:
502 uci_to_section(e)->type = str;
503 break;
504 case UCI_TYPE_OPTION:
505 uci_to_option(e)->v.string = str;
506 break;
507 default:
508 break;
509 }
510
511 return 0;
512 }
513
514 int uci_rename(struct uci_context *ctx, struct uci_package *p, char *section, char *option, char *name)
515 {
516 /* NB: UCI_INTERNAL use means without history tracking */
517 bool internal = ctx->internal;
518 struct uci_element *e;
519
520 UCI_HANDLE_ERR(ctx);
521
522 /* NB: p, section, option validated by uci_lookup */
523 UCI_INTERNAL(uci_lookup, ctx, &e, p, section, option);
524
525 if (!internal && p->has_history)
526 uci_add_history(ctx, &p->history, UCI_CMD_RENAME, section, option, name);
527
528 name = uci_strdup(ctx, name);
529 if (e->name)
530 free(e->name);
531 e->name = name;
532
533 return 0;
534 }
535
536 int uci_add_section(struct uci_context *ctx, struct uci_package *p, const char *type, struct uci_section **res)
537 {
538 bool internal = ctx->internal;
539 struct uci_section *s;
540
541 UCI_HANDLE_ERR(ctx);
542 UCI_ASSERT(ctx, p != NULL);
543 s = uci_alloc_section(p, type, NULL);
544 uci_fixup_section(ctx, s);
545 *res = s;
546 if (!internal && p->has_history)
547 uci_add_history(ctx, &p->history, UCI_CMD_ADD, s->e.name, NULL, type);
548
549 return 0;
550 }
551
552 int uci_delete(struct uci_context *ctx, struct uci_package *p, const char *section, const char *option)
553 {
554 /* NB: pass on internal flag to uci_del_element */
555 bool internal = ctx->internal;
556 struct uci_element *e;
557
558 UCI_HANDLE_ERR(ctx);
559
560 /* NB: p, section, option validated by uci_lookup */
561 UCI_INTERNAL(uci_lookup, ctx, &e, p, section, option);
562
563 ctx->internal = internal;
564 return uci_del_element(ctx, e);
565 }
566
567 int uci_set(struct uci_context *ctx, struct uci_package *p, const char *section, const char *option, const char *value, struct uci_element **result)
568 {
569 /* NB: UCI_INTERNAL use means without history tracking */
570 bool internal = ctx->internal;
571 struct uci_element *e = NULL;
572 struct uci_section *s = NULL;
573 struct uci_option *o = NULL;
574
575 UCI_HANDLE_ERR(ctx);
576 UCI_ASSERT(ctx, p != NULL);
577 UCI_ASSERT(ctx, uci_validate_name(section));
578 if (option) {
579 UCI_ASSERT(ctx, uci_validate_name(option));
580 UCI_ASSERT(ctx, value != NULL);
581 } else {
582 UCI_ASSERT(ctx, uci_validate_str(value, false));
583 }
584
585 /*
586 * look up the package, section and option (if set)
587 * if the section/option is to be modified and it is not found
588 * create a new element in the appropriate list
589 */
590 e = uci_lookup_list(&p->sections, section);
591 if (!e)
592 goto notfound;
593
594 s = uci_to_section(e);
595 if (ctx->pctx && ctx->pctx->merge)
596 ctx->pctx->section = s;
597
598 if (option) {
599 e = uci_lookup_list(&s->options, option);
600 if (!e)
601 goto notfound;
602 o = uci_to_option(e);
603 }
604
605 /*
606 * no unknown element was supplied, assume that we can just update
607 * an existing entry
608 */
609 if (o)
610 e = &o->e;
611 else
612 e = &s->e;
613 if (result)
614 *result = e;
615 else
616 result = &e;
617
618 ctx->internal = internal;
619 return uci_set_element_value(ctx, result, value);
620
621 notfound:
622 /*
623 * the entry that we need to update was not found,
624 * check if the search failed prematurely.
625 * this can happen if the package was not found, or if
626 * an option was supplied, but the section wasn't found
627 */
628 if (!p || (!s && option))
629 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
630
631 /* now add the missing entry */
632 if (!internal && p->has_history)
633 uci_add_history(ctx, &p->history, UCI_CMD_CHANGE, section, option, value);
634 if (s) {
635 o = uci_alloc_option(s, option, value);
636 if (result)
637 *result = &o->e;
638 } else {
639 s = uci_alloc_section(p, value, section);
640 if (result)
641 *result = &s->e;
642 if (ctx->pctx && ctx->pctx->merge)
643 ctx->pctx->section = s;
644 }
645
646 return 0;
647 }
648
649 int uci_unload(struct uci_context *ctx, struct uci_package *p)
650 {
651 UCI_HANDLE_ERR(ctx);
652 UCI_ASSERT(ctx, p != NULL);
653
654 uci_free_package(&p);
655 return 0;
656 }
657