Sync ref test result with current implementation.
[project/uci.git] / delta.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 /*
16 * This file contains the code for handling uci config delta files
17 */
18
19 #define _GNU_SOURCE
20 #include <sys/types.h>
21 #include <sys/stat.h>
22 #include <sys/file.h>
23 #include <stdbool.h>
24 #include <unistd.h>
25 #include <fcntl.h>
26 #include <stdio.h>
27 #include <ctype.h>
28 #include <string.h>
29 #include <stdlib.h>
30
31 #include "uci.h"
32 #include "uci_internal.h"
33
34 /* record a change that was done to a package */
35 void
36 uci_add_delta(struct uci_context *ctx, struct uci_list *list, int cmd, const char *section, const char *option, const char *value)
37 {
38 struct uci_delta *h;
39 int size = strlen(section) + 1;
40 char *ptr;
41
42 if (value)
43 size += strlen(value) + 1;
44
45 h = uci_alloc_element(ctx, delta, option, size);
46 ptr = uci_dataptr(h);
47 h->cmd = cmd;
48 h->section = strcpy(ptr, section);
49 if (value) {
50 ptr += strlen(ptr) + 1;
51 h->value = strcpy(ptr, value);
52 }
53 uci_list_add(list, &h->e.list);
54 }
55
56 void
57 uci_free_delta(struct uci_delta *h)
58 {
59 if (!h)
60 return;
61 if ((h->section != NULL) &&
62 (h->section != uci_dataptr(h))) {
63 free(h->section);
64 free(h->value);
65 }
66 uci_free_element(&h->e);
67 }
68
69
70 int uci_set_savedir(struct uci_context *ctx, const char *dir)
71 {
72 char *sdir;
73
74 UCI_HANDLE_ERR(ctx);
75 UCI_ASSERT(ctx, dir != NULL);
76
77 sdir = uci_strdup(ctx, dir);
78 if (ctx->savedir != uci_savedir)
79 free(ctx->savedir);
80 ctx->savedir = sdir;
81 return 0;
82 }
83
84 int uci_add_delta_path(struct uci_context *ctx, const char *dir)
85 {
86 struct uci_element *e;
87
88 UCI_HANDLE_ERR(ctx);
89 UCI_ASSERT(ctx, dir != NULL);
90 e = uci_alloc_generic(ctx, UCI_TYPE_PATH, dir, sizeof(struct uci_element));
91 uci_list_add(&ctx->delta_path, &e->list);
92
93 return 0;
94 }
95
96 static inline int uci_parse_delta_tuple(struct uci_context *ctx, char **buf, struct uci_ptr *ptr)
97 {
98 int c = UCI_CMD_CHANGE;
99
100 switch(**buf) {
101 case '^':
102 c = UCI_CMD_REORDER;
103 break;
104 case '-':
105 c = UCI_CMD_REMOVE;
106 break;
107 case '@':
108 c = UCI_CMD_RENAME;
109 break;
110 case '+':
111 /* UCI_CMD_ADD is used for anonymous sections or list values */
112 c = UCI_CMD_ADD;
113 break;
114 case '|':
115 c = UCI_CMD_LIST_ADD;
116 break;
117 case '~':
118 c = UCI_CMD_LIST_DEL;
119 break;
120 }
121
122 if (c != UCI_CMD_CHANGE)
123 *buf += 1;
124
125 UCI_INTERNAL(uci_parse_ptr, ctx, ptr, *buf);
126
127 if (!ptr->section)
128 goto error;
129 if (ptr->flags & UCI_LOOKUP_EXTENDED)
130 goto error;
131
132 switch(c) {
133 case UCI_CMD_REORDER:
134 if (!ptr->value || ptr->option)
135 goto error;
136 break;
137 case UCI_CMD_RENAME:
138 if (!ptr->value || !uci_validate_name(ptr->value))
139 goto error;
140 break;
141 case UCI_CMD_LIST_ADD:
142 if (!ptr->option)
143 goto error;
144 case UCI_CMD_LIST_DEL:
145 if (!ptr->option)
146 goto error;
147 }
148
149 return c;
150
151 error:
152 UCI_THROW(ctx, UCI_ERR_INVAL);
153 return 0;
154 }
155
156 static void uci_parse_delta_line(struct uci_context *ctx, struct uci_package *p, char *buf)
157 {
158 struct uci_element *e = NULL;
159 struct uci_ptr ptr;
160 int cmd;
161
162 cmd = uci_parse_delta_tuple(ctx, &buf, &ptr);
163 if (strcmp(ptr.package, p->e.name) != 0)
164 goto error;
165
166 if (ctx->flags & UCI_FLAG_SAVED_DELTA)
167 uci_add_delta(ctx, &p->saved_delta, cmd, ptr.section, ptr.option, ptr.value);
168
169 switch(cmd) {
170 case UCI_CMD_REORDER:
171 uci_expand_ptr(ctx, &ptr, true);
172 if (!ptr.s)
173 UCI_THROW(ctx, UCI_ERR_NOTFOUND);
174 UCI_INTERNAL(uci_reorder_section, ctx, ptr.s, strtoul(ptr.value, NULL, 10));
175 break;
176 case UCI_CMD_RENAME:
177 UCI_INTERNAL(uci_rename, ctx, &ptr);
178 break;
179 case UCI_CMD_REMOVE:
180 UCI_INTERNAL(uci_delete, ctx, &ptr);
181 break;
182 case UCI_CMD_LIST_ADD:
183 UCI_INTERNAL(uci_add_list, ctx, &ptr);
184 break;
185 case UCI_CMD_LIST_DEL:
186 UCI_INTERNAL(uci_del_list, ctx, &ptr);
187 break;
188 case UCI_CMD_ADD:
189 case UCI_CMD_CHANGE:
190 UCI_INTERNAL(uci_set, ctx, &ptr);
191 e = ptr.last;
192 if (!ptr.option && e && (cmd == UCI_CMD_ADD))
193 uci_to_section(e)->anonymous = true;
194 break;
195 }
196 return;
197 error:
198 UCI_THROW(ctx, UCI_ERR_PARSE);
199 }
200
201 /* returns the number of changes that were successfully parsed */
202 static int uci_parse_delta(struct uci_context *ctx, FILE *stream, struct uci_package *p)
203 {
204 struct uci_parse_context *pctx;
205 int changes = 0;
206
207 /* make sure no memory from previous parse attempts is leaked */
208 uci_cleanup(ctx);
209
210 pctx = (struct uci_parse_context *) uci_malloc(ctx, sizeof(struct uci_parse_context));
211 ctx->pctx = pctx;
212 pctx->file = stream;
213
214 while (!feof(pctx->file)) {
215 uci_getln(ctx, 0);
216 if (!pctx->buf[0])
217 continue;
218
219 /*
220 * ignore parse errors in single lines, we want to preserve as much
221 * delta as possible
222 */
223 UCI_TRAP_SAVE(ctx, error);
224 uci_parse_delta_line(ctx, p, pctx->buf);
225 UCI_TRAP_RESTORE(ctx);
226 changes++;
227 error:
228 continue;
229 }
230
231 /* no error happened, we can get rid of the parser context now */
232 uci_cleanup(ctx);
233 return changes;
234 }
235
236 /* returns the number of changes that were successfully parsed */
237 static int uci_load_delta_file(struct uci_context *ctx, struct uci_package *p, char *filename, FILE **f, bool flush)
238 {
239 FILE *stream = NULL;
240 int changes = 0;
241
242 UCI_TRAP_SAVE(ctx, done);
243 stream = uci_open_stream(ctx, filename, NULL, SEEK_SET, flush, false);
244 if (p)
245 changes = uci_parse_delta(ctx, stream, p);
246 UCI_TRAP_RESTORE(ctx);
247 done:
248 if (f)
249 *f = stream;
250 else if (stream)
251 uci_close_stream(stream);
252 return changes;
253 }
254
255 /* returns the number of changes that were successfully parsed */
256 __private int uci_load_delta(struct uci_context *ctx, struct uci_package *p, bool flush)
257 {
258 struct uci_element *e;
259 char *filename = NULL;
260 FILE *f = NULL;
261 int changes = 0;
262
263 if (!p->has_delta)
264 return 0;
265
266 uci_foreach_element(&ctx->delta_path, e) {
267 if ((asprintf(&filename, "%s/%s", e->name, p->e.name) < 0) || !filename)
268 UCI_THROW(ctx, UCI_ERR_MEM);
269
270 uci_load_delta_file(ctx, p, filename, NULL, false);
271 free(filename);
272 }
273
274 if ((asprintf(&filename, "%s/%s", ctx->savedir, p->e.name) < 0) || !filename)
275 UCI_THROW(ctx, UCI_ERR_MEM);
276
277 changes = uci_load_delta_file(ctx, p, filename, &f, flush);
278 if (flush && f && (changes > 0)) {
279 rewind(f);
280 if (ftruncate(fileno(f), 0) < 0) {
281 uci_close_stream(f);
282 UCI_THROW(ctx, UCI_ERR_IO);
283 }
284 }
285 free(filename);
286 uci_close_stream(f);
287 ctx->err = 0;
288 return changes;
289 }
290
291 static void uci_filter_delta(struct uci_context *ctx, const char *name, const char *section, const char *option)
292 {
293 struct uci_parse_context *pctx;
294 struct uci_element *e, *tmp;
295 struct uci_list list;
296 char *filename = NULL;
297 struct uci_ptr ptr;
298 FILE *f = NULL;
299
300 uci_list_init(&list);
301 uci_alloc_parse_context(ctx);
302 pctx = ctx->pctx;
303
304 if ((asprintf(&filename, "%s/%s", ctx->savedir, name) < 0) || !filename)
305 UCI_THROW(ctx, UCI_ERR_MEM);
306
307 UCI_TRAP_SAVE(ctx, done);
308 f = uci_open_stream(ctx, filename, NULL, SEEK_SET, true, false);
309 pctx->file = f;
310 while (!feof(f)) {
311 struct uci_element *e;
312 char *buf;
313
314 uci_getln(ctx, 0);
315 buf = pctx->buf;
316 if (!buf[0])
317 continue;
318
319 /* NB: need to allocate the element before the call to
320 * uci_parse_delta_tuple, otherwise the original string
321 * gets modified before it is saved */
322 e = uci_alloc_generic(ctx, UCI_TYPE_DELTA, pctx->buf, sizeof(struct uci_element));
323 uci_list_add(&list, &e->list);
324
325 uci_parse_delta_tuple(ctx, &buf, &ptr);
326 if (section) {
327 if (!ptr.section || (strcmp(section, ptr.section) != 0))
328 continue;
329 }
330 if (option) {
331 if (!ptr.option || (strcmp(option, ptr.option) != 0))
332 continue;
333 }
334 /* match, drop this element again */
335 uci_free_element(e);
336 }
337
338 /* rebuild the delta file */
339 rewind(f);
340 if (ftruncate(fileno(f), 0) < 0)
341 UCI_THROW(ctx, UCI_ERR_IO);
342 uci_foreach_element_safe(&list, tmp, e) {
343 fprintf(f, "%s\n", e->name);
344 uci_free_element(e);
345 }
346 UCI_TRAP_RESTORE(ctx);
347
348 done:
349 free(filename);
350 uci_close_stream(pctx->file);
351 uci_foreach_element_safe(&list, tmp, e) {
352 uci_free_element(e);
353 }
354 uci_cleanup(ctx);
355 }
356
357 int uci_revert(struct uci_context *ctx, struct uci_ptr *ptr)
358 {
359 char *package = NULL;
360 char *section = NULL;
361 char *option = NULL;
362
363 UCI_HANDLE_ERR(ctx);
364 uci_expand_ptr(ctx, ptr, false);
365 UCI_ASSERT(ctx, ptr->p->has_delta);
366
367 /*
368 * - flush unwritten changes
369 * - save the package name
370 * - unload the package
371 * - filter the delta
372 * - reload the package
373 */
374 UCI_TRAP_SAVE(ctx, error);
375 UCI_INTERNAL(uci_save, ctx, ptr->p);
376
377 /* NB: need to clone package, section and option names,
378 * as they may get freed on uci_free_package() */
379 package = uci_strdup(ctx, ptr->p->e.name);
380 if (ptr->section)
381 section = uci_strdup(ctx, ptr->section);
382 if (ptr->option)
383 option = uci_strdup(ctx, ptr->option);
384
385 uci_free_package(&ptr->p);
386 uci_filter_delta(ctx, package, section, option);
387
388 UCI_INTERNAL(uci_load, ctx, package, &ptr->p);
389 UCI_TRAP_RESTORE(ctx);
390 ctx->err = 0;
391
392 error:
393 free(package);
394 free(section);
395 free(option);
396 if (ctx->err)
397 UCI_THROW(ctx, ctx->err);
398 return 0;
399 }
400
401 int uci_save(struct uci_context *ctx, struct uci_package *p)
402 {
403 FILE *f = NULL;
404 char *filename = NULL;
405 struct uci_element *e, *tmp;
406 struct stat statbuf;
407
408 UCI_HANDLE_ERR(ctx);
409 UCI_ASSERT(ctx, p != NULL);
410
411 /*
412 * if the config file was outside of the /etc/config path,
413 * don't save the delta to a file, update the real file
414 * directly.
415 * does not modify the uci_package pointer
416 */
417 if (!p->has_delta)
418 return uci_commit(ctx, &p, false);
419
420 if (uci_list_empty(&p->delta))
421 return 0;
422
423 if (stat(ctx->savedir, &statbuf) < 0) {
424 if (stat(ctx->confdir, &statbuf) == 0) {
425 mkdir(ctx->savedir, statbuf.st_mode);
426 } else {
427 mkdir(ctx->savedir, UCI_DIRMODE);
428 }
429 } else if ((statbuf.st_mode & S_IFMT) != S_IFDIR) {
430 UCI_THROW(ctx, UCI_ERR_IO);
431 }
432
433 if ((asprintf(&filename, "%s/%s", ctx->savedir, p->e.name) < 0) || !filename)
434 UCI_THROW(ctx, UCI_ERR_MEM);
435
436 ctx->err = 0;
437 UCI_TRAP_SAVE(ctx, done);
438 f = uci_open_stream(ctx, filename, NULL, SEEK_END, true, true);
439 UCI_TRAP_RESTORE(ctx);
440
441 uci_foreach_element_safe(&p->delta, tmp, e) {
442 struct uci_delta *h = uci_to_delta(e);
443 char *prefix = "";
444
445 switch(h->cmd) {
446 case UCI_CMD_REMOVE:
447 prefix = "-";
448 break;
449 case UCI_CMD_RENAME:
450 prefix = "@";
451 break;
452 case UCI_CMD_ADD:
453 prefix = "+";
454 break;
455 case UCI_CMD_REORDER:
456 prefix = "^";
457 break;
458 case UCI_CMD_LIST_ADD:
459 prefix = "|";
460 break;
461 case UCI_CMD_LIST_DEL:
462 prefix = "~";
463 break;
464 default:
465 break;
466 }
467
468 fprintf(f, "%s%s.%s", prefix, p->e.name, h->section);
469 if (e->name)
470 fprintf(f, ".%s", e->name);
471
472 if (h->cmd == UCI_CMD_REMOVE && !h->value)
473 fprintf(f, "\n");
474 else
475 fprintf(f, "=%s\n", h->value);
476 uci_free_delta(h);
477 }
478
479 done:
480 uci_close_stream(f);
481 free(filename);
482 if (ctx->err)
483 UCI_THROW(ctx, ctx->err);
484
485 return 0;
486 }
487
488