24382c8464d090746d416fa45e5caef5b213b8b8
[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->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 /* record a change that was done to a package */
155 static void
156 uci_add_history(struct uci_context *ctx, struct uci_package *p, int cmd, char *section, char *option, char *value)
157 {
158 struct uci_history *h;
159 int size = strlen(section) + 1;
160 char *ptr;
161
162 if (!p->confdir)
163 return;
164
165 if (value)
166 size += strlen(value) + 1;
167
168 h = uci_alloc_element(ctx, history, option, size);
169 ptr = uci_dataptr(h);
170 h->cmd = cmd;
171 h->section = strcpy(ptr, section);
172 if (value) {
173 ptr += strlen(ptr) + 1;
174 h->value = strcpy(ptr, value);
175 }
176 uci_list_add(&p->history, &h->e.list);
177 }
178
179 static void
180 uci_free_history(struct uci_history *h)
181 {
182 if (!h)
183 return;
184 if ((h->section != NULL) &&
185 (h->section != uci_dataptr(h))) {
186 free(h->section);
187 free(h->value);
188 }
189 uci_free_element(&h->e);
190 }
191
192 static struct uci_package *
193 uci_alloc_package(struct uci_context *ctx, const char *name)
194 {
195 struct uci_package *p;
196
197 p = uci_alloc_element(ctx, package, name, 0);
198 p->ctx = ctx;
199 uci_list_init(&p->sections);
200 uci_list_init(&p->history);
201 return p;
202 }
203
204 static void
205 uci_free_package(struct uci_package **package)
206 {
207 struct uci_element *e, *tmp;
208 struct uci_package *p = *package;
209
210 if(!p)
211 return;
212
213 if (p->path)
214 free(p->path);
215 uci_foreach_element_safe(&p->sections, tmp, e) {
216 uci_free_section(uci_to_section(e));
217 }
218 uci_foreach_element_safe(&p->history, tmp, e) {
219 uci_free_history(uci_to_history(e));
220 }
221 uci_free_element(&p->e);
222 *package = NULL;
223 }
224
225 static struct uci_element *uci_lookup_list(struct uci_context *ctx, struct uci_list *list, const char *name)
226 {
227 struct uci_element *e;
228
229 uci_foreach_element(list, e) {
230 if (!strcmp(e->name, name))
231 return e;
232 }
233 return NULL;
234 }
235
236 int uci_lookup(struct uci_context *ctx, struct uci_element **res, struct uci_package *p, char *section, char *option)
237 {
238 struct uci_element *e;
239 struct uci_section *s;
240
241 UCI_HANDLE_ERR(ctx);
242 UCI_ASSERT(ctx, res != NULL);
243 UCI_ASSERT(ctx, p != NULL);
244 UCI_ASSERT(ctx, uci_validate_name(section));
245 if (option)
246 UCI_ASSERT(ctx, uci_validate_name(option));
247
248 e = uci_lookup_list(ctx, &p->sections, section);
249 if (!e)
250 goto notfound;
251
252 if (option) {
253 s = uci_to_section(e);
254 e = uci_lookup_list(ctx, &s->options, option);
255 }
256
257 *res = e;
258 return 0;
259
260 notfound:
261 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
262 return 0;
263 }
264
265 int uci_del_element(struct uci_context *ctx, struct uci_element *e)
266 {
267 /* NB: UCI_INTERNAL use means without history tracking */
268 bool internal = ctx->internal;
269 struct uci_package *p = NULL;
270 struct uci_section *s = NULL;
271 struct uci_option *o = NULL;
272 struct uci_element *i, *tmp;
273 char *option = NULL;
274
275 UCI_HANDLE_ERR(ctx);
276 UCI_ASSERT(ctx, e != NULL);
277
278 switch(e->type) {
279 case UCI_TYPE_SECTION:
280 s = uci_to_section(e);
281 uci_foreach_element_safe(&s->options, tmp, i) {
282 uci_del_element(ctx, i);
283 }
284 break;
285 case UCI_TYPE_OPTION:
286 o = uci_to_option(e);
287 s = o->section;
288 p = s->package;
289 option = e->name;
290 break;
291 default:
292 UCI_THROW(ctx, UCI_ERR_INVAL);
293 break;
294 }
295
296 p = s->package;
297 if (!internal)
298 uci_add_history(ctx, p, UCI_CMD_REMOVE, s->e.name, option, NULL);
299
300 switch(e->type) {
301 case UCI_TYPE_SECTION:
302 uci_free_section(s);
303 break;
304 case UCI_TYPE_OPTION:
305 uci_free_option(o);
306 break;
307 default:
308 break;
309 }
310 return 0;
311 }
312
313 int uci_set_element_value(struct uci_context *ctx, struct uci_element **element, char *value)
314 {
315 /* NB: UCI_INTERNAL use means without history tracking */
316 bool internal = ctx->internal;
317 struct uci_list *list;
318 struct uci_element *e;
319 struct uci_package *p;
320 struct uci_section *s;
321 char *section;
322 char *option;
323 char *str;
324 int size;
325
326 UCI_HANDLE_ERR(ctx);
327 UCI_ASSERT(ctx, (element != NULL) && (*element != NULL));
328
329 /* what the 'value' of an element means depends on the type
330 * for a section, the 'value' means its type
331 * for an option, the 'value' means its value string
332 * when changing the value, shrink the element to its actual size
333 * (it may have been allocated with a bigger size, to include
334 * its buffer)
335 * then duplicate the string passed on the command line and
336 * insert it into the structure.
337 */
338 e = *element;
339 list = e->list.prev;
340 switch(e->type) {
341 case UCI_TYPE_SECTION:
342 UCI_ASSERT(ctx, uci_validate_str(value, false));
343 size = sizeof(struct uci_section);
344 s = uci_to_section(e);
345 section = e->name;
346 option = NULL;
347 break;
348 case UCI_TYPE_OPTION:
349 UCI_ASSERT(ctx, value != NULL);
350 size = sizeof(struct uci_option);
351 s = uci_to_option(e)->section;
352 section = s->e.name;
353 option = e->name;
354 break;
355 default:
356 UCI_THROW(ctx, UCI_ERR_INVAL);
357 return 0;
358 }
359 p = s->package;
360 if (!internal)
361 uci_add_history(ctx, p, UCI_CMD_CHANGE, section, option, value);
362
363 uci_list_del(&e->list);
364 e = uci_realloc(ctx, e, size);
365 str = uci_strdup(ctx, value);
366 uci_list_insert(list, &e->list);
367 *element = e;
368
369 switch(e->type) {
370 case UCI_TYPE_SECTION:
371 uci_to_section(e)->type = str;
372 break;
373 case UCI_TYPE_OPTION:
374 uci_to_option(e)->value = str;
375 break;
376 default:
377 break;
378 }
379
380 return 0;
381 }
382
383 int uci_rename(struct uci_context *ctx, struct uci_package *p, char *section, char *option, char *name)
384 {
385 /* NB: UCI_INTERNAL use means without history tracking */
386 bool internal = ctx->internal;
387 struct uci_element *e;
388
389 UCI_HANDLE_ERR(ctx);
390
391 /* NB: p, section, option validated by uci_lookup */
392 UCI_INTERNAL(uci_lookup, ctx, &e, p, section, option);
393
394 if (!internal)
395 uci_add_history(ctx, p, UCI_CMD_RENAME, section, option, name);
396
397 name = uci_strdup(ctx, name);
398 if (e->name)
399 free(e->name);
400 e->name = name;
401
402 return 0;
403 }
404
405
406 int uci_delete(struct uci_context *ctx, struct uci_package *p, char *section, char *option)
407 {
408 /* NB: pass on internal flag to uci_del_element */
409 bool internal = ctx->internal;
410 struct uci_element *e;
411
412 UCI_HANDLE_ERR(ctx);
413
414 /* NB: p, section, option validated by uci_lookup */
415 UCI_INTERNAL(uci_lookup, ctx, &e, p, section, option);
416
417 ctx->internal = internal;
418 return uci_del_element(ctx, e);
419 }
420
421 int uci_set(struct uci_context *ctx, struct uci_package *p, char *section, char *option, char *value)
422 {
423 /* NB: UCI_INTERNAL use means without history tracking */
424 bool internal = ctx->internal;
425 struct uci_element *e = NULL;
426 struct uci_section *s = NULL;
427 struct uci_option *o = NULL;
428
429 UCI_HANDLE_ERR(ctx);
430 UCI_ASSERT(ctx, p != NULL);
431 UCI_ASSERT(ctx, uci_validate_name(section));
432 if (option) {
433 UCI_ASSERT(ctx, uci_validate_name(option));
434 UCI_ASSERT(ctx, value != NULL);
435 } else {
436 UCI_ASSERT(ctx, uci_validate_str(value, false));
437 }
438
439 /*
440 * look up the package, section and option (if set)
441 * if the section/option is to be modified and it is not found
442 * create a new element in the appropriate list
443 */
444 e = uci_lookup_list(ctx, &p->sections, section);
445 if (!e)
446 goto notfound;
447
448 s = uci_to_section(e);
449 if (ctx->pctx && ctx->pctx->merge)
450 ctx->pctx->section = s;
451
452 if (option) {
453 e = uci_lookup_list(ctx, &s->options, option);
454 if (!e)
455 goto notfound;
456 o = uci_to_option(e);
457 }
458
459 /*
460 * no unknown element was supplied, assume that we can just update
461 * an existing entry
462 */
463 if (o)
464 e = &o->e;
465 else
466 e = &s->e;
467
468 ctx->internal = internal;
469 return uci_set_element_value(ctx, &e, value);
470
471 notfound:
472 /*
473 * the entry that we need to update was not found,
474 * check if the search failed prematurely.
475 * this can happen if the package was not found, or if
476 * an option was supplied, but the section wasn't found
477 */
478 if (!p || (!s && option))
479 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
480
481 /* now add the missing entry */
482 if (!internal)
483 uci_add_history(ctx, p, UCI_CMD_ADD, section, option, value);
484 if (s)
485 uci_alloc_option(s, option, value);
486 else {
487 s = uci_alloc_section(p, value, section);
488 if (ctx->pctx && ctx->pctx->merge)
489 ctx->pctx->section = s;
490 }
491
492 return 0;
493 }
494
495 int uci_unload(struct uci_context *ctx, struct uci_package *p)
496 {
497 UCI_HANDLE_ERR(ctx);
498 UCI_ASSERT(ctx, p != NULL);
499
500 uci_free_package(&p);
501 return 0;
502 }
503