blob: 7424edeb813f09eec5e255624d58a479ef688c1e
1 | /* vi: set sw=4 ts=4: */ |
2 | /* |
3 | * tag.c - allocation/initialization/free routines for tag structs |
4 | * |
5 | * Copyright (C) 2001 Andreas Dilger |
6 | * Copyright (C) 2003 Theodore Ts'o |
7 | * |
8 | * %Begin-Header% |
9 | * This file may be redistributed under the terms of the |
10 | * GNU Lesser General Public License. |
11 | * %End-Header% |
12 | */ |
13 | |
14 | #include <stdlib.h> |
15 | #include <string.h> |
16 | #include <stdio.h> |
17 | |
18 | #include "blkidP.h" |
19 | |
20 | static blkid_tag blkid_new_tag(void) |
21 | { |
22 | blkid_tag tag; |
23 | |
24 | tag = xzalloc(sizeof(struct blkid_struct_tag)); |
25 | |
26 | INIT_LIST_HEAD(&tag->bit_tags); |
27 | INIT_LIST_HEAD(&tag->bit_names); |
28 | |
29 | return tag; |
30 | } |
31 | |
32 | #ifdef CONFIG_BLKID_DEBUG |
33 | void blkid_debug_dump_tag(blkid_tag tag) |
34 | { |
35 | if (!tag) { |
36 | printf(" tag: NULL\n"); |
37 | return; |
38 | } |
39 | |
40 | printf(" tag: %s=\"%s\"\n", tag->bit_name, tag->bit_val); |
41 | } |
42 | #endif |
43 | |
44 | void blkid_free_tag(blkid_tag tag) |
45 | { |
46 | if (!tag) |
47 | return; |
48 | |
49 | DBG(DEBUG_TAG, printf(" freeing tag %s=%s\n", tag->bit_name, |
50 | tag->bit_val ? tag->bit_val : "(NULL)")); |
51 | DBG(DEBUG_TAG, blkid_debug_dump_tag(tag)); |
52 | |
53 | list_del(&tag->bit_tags); /* list of tags for this device */ |
54 | list_del(&tag->bit_names); /* list of tags with this type */ |
55 | |
56 | free(tag->bit_name); |
57 | free(tag->bit_val); |
58 | free(tag); |
59 | } |
60 | |
61 | /* |
62 | * Find the desired tag on a device. If value is NULL, then the |
63 | * first such tag is returned, otherwise return only exact tag if found. |
64 | */ |
65 | blkid_tag blkid_find_tag_dev(blkid_dev dev, const char *type) |
66 | { |
67 | struct list_head *p; |
68 | |
69 | if (!dev || !type) |
70 | return NULL; |
71 | |
72 | list_for_each(p, &dev->bid_tags) { |
73 | blkid_tag tmp = list_entry(p, struct blkid_struct_tag, |
74 | bit_tags); |
75 | |
76 | if (!strcmp(tmp->bit_name, type)) |
77 | return tmp; |
78 | } |
79 | return NULL; |
80 | } |
81 | |
82 | /* |
83 | * Find the desired tag type in the cache. |
84 | * We return the head tag for this tag type. |
85 | */ |
86 | static blkid_tag blkid_find_head_cache(blkid_cache cache, const char *type) |
87 | { |
88 | blkid_tag head = NULL, tmp; |
89 | struct list_head *p; |
90 | |
91 | if (!cache || !type) |
92 | return NULL; |
93 | |
94 | list_for_each(p, &cache->bic_tags) { |
95 | tmp = list_entry(p, struct blkid_struct_tag, bit_tags); |
96 | if (!strcmp(tmp->bit_name, type)) { |
97 | DBG(DEBUG_TAG, |
98 | printf(" found cache tag head %s\n", type)); |
99 | head = tmp; |
100 | break; |
101 | } |
102 | } |
103 | return head; |
104 | } |
105 | |
106 | /* |
107 | * Set a tag on an existing device. |
108 | * |
109 | * If value is NULL, then delete the tagsfrom the device. |
110 | */ |
111 | int blkid_set_tag(blkid_dev dev, const char *name, |
112 | const char *value, const int vlength) |
113 | { |
114 | blkid_tag t = 0, head = 0; |
115 | char *val = NULL; |
116 | |
117 | if (!dev || !name) |
118 | return -BLKID_ERR_PARAM; |
119 | |
120 | if (!(val = blkid_strndup(value, vlength)) && value) |
121 | return -BLKID_ERR_MEM; |
122 | t = blkid_find_tag_dev(dev, name); |
123 | if (!value) { |
124 | blkid_free_tag(t); |
125 | } else if (t) { |
126 | if (!strcmp(t->bit_val, val)) { |
127 | /* Same thing, exit */ |
128 | free(val); |
129 | return 0; |
130 | } |
131 | free(t->bit_val); |
132 | t->bit_val = val; |
133 | } else { |
134 | /* Existing tag not present, add to device */ |
135 | if (!(t = blkid_new_tag())) |
136 | goto errout; |
137 | t->bit_name = blkid_strdup(name); |
138 | t->bit_val = val; |
139 | t->bit_dev = dev; |
140 | |
141 | list_add_tail(&t->bit_tags, &dev->bid_tags); |
142 | |
143 | if (dev->bid_cache) { |
144 | head = blkid_find_head_cache(dev->bid_cache, |
145 | t->bit_name); |
146 | if (!head) { |
147 | head = blkid_new_tag(); |
148 | if (!head) |
149 | goto errout; |
150 | |
151 | DBG(DEBUG_TAG, |
152 | printf(" creating new cache tag head %s\n", name)); |
153 | head->bit_name = blkid_strdup(name); |
154 | if (!head->bit_name) |
155 | goto errout; |
156 | list_add_tail(&head->bit_tags, |
157 | &dev->bid_cache->bic_tags); |
158 | } |
159 | list_add_tail(&t->bit_names, &head->bit_names); |
160 | } |
161 | } |
162 | |
163 | /* Link common tags directly to the device struct */ |
164 | if (!strcmp(name, "TYPE")) |
165 | dev->bid_type = val; |
166 | else if (!strcmp(name, "LABEL")) |
167 | dev->bid_label = val; |
168 | else if (!strcmp(name, "UUID")) |
169 | dev->bid_uuid = val; |
170 | |
171 | if (dev->bid_cache) |
172 | dev->bid_cache->bic_flags |= BLKID_BIC_FL_CHANGED; |
173 | return 0; |
174 | |
175 | errout: |
176 | blkid_free_tag(t); |
177 | if (!t) |
178 | free(val); |
179 | blkid_free_tag(head); |
180 | return -BLKID_ERR_MEM; |
181 | } |
182 | |
183 | |
184 | /* |
185 | * Parse a "NAME=value" string. This is slightly different than |
186 | * parse_token, because that will end an unquoted value at a space, while |
187 | * this will assume that an unquoted value is the rest of the token (e.g. |
188 | * if we are passed an already quoted string from the command-line we don't |
189 | * have to both quote and escape quote so that the quotes make it to |
190 | * us). |
191 | * |
192 | * Returns 0 on success, and -1 on failure. |
193 | */ |
194 | int blkid_parse_tag_string(const char *token, char **ret_type, char **ret_val) |
195 | { |
196 | char *name, *value, *cp; |
197 | |
198 | DBG(DEBUG_TAG, printf("trying to parse '%s' as a tag\n", token)); |
199 | |
200 | if (!token || !(cp = strchr(token, '='))) |
201 | return -1; |
202 | |
203 | name = blkid_strdup(token); |
204 | if (!name) |
205 | return -1; |
206 | value = name + (cp - token); |
207 | *value++ = '\0'; |
208 | if (*value == '"' || *value == '\'') { |
209 | char c = *value++; |
210 | if (!(cp = strrchr(value, c))) |
211 | goto errout; /* missing closing quote */ |
212 | *cp = '\0'; |
213 | } |
214 | value = blkid_strdup(value); |
215 | if (!value) |
216 | goto errout; |
217 | |
218 | *ret_type = name; |
219 | *ret_val = value; |
220 | |
221 | return 0; |
222 | |
223 | errout: |
224 | free(name); |
225 | return -1; |
226 | } |
227 | |
228 | /* |
229 | * Tag iteration routines for the public libblkid interface. |
230 | * |
231 | * These routines do not expose the list.h implementation, which are a |
232 | * contamination of the namespace, and which force us to reveal far, far |
233 | * too much of our internal implemenation. I'm not convinced I want |
234 | * to keep list.h in the long term, anyway. It's fine for kernel |
235 | * programming, but performance is not the #1 priority for this |
236 | * library, and I really don't like the tradeoff of type-safety for |
237 | * performance for this application. [tytso:20030125.2007EST] |
238 | */ |
239 | |
240 | /* |
241 | * This series of functions iterate over all tags in a device |
242 | */ |
243 | #define TAG_ITERATE_MAGIC 0x01a5284c |
244 | |
245 | struct blkid_struct_tag_iterate { |
246 | int magic; |
247 | blkid_dev dev; |
248 | struct list_head *p; |
249 | }; |
250 | |
251 | blkid_tag_iterate blkid_tag_iterate_begin(blkid_dev dev) |
252 | { |
253 | blkid_tag_iterate iter; |
254 | |
255 | iter = xmalloc(sizeof(struct blkid_struct_tag_iterate)); |
256 | iter->magic = TAG_ITERATE_MAGIC; |
257 | iter->dev = dev; |
258 | iter->p = dev->bid_tags.next; |
259 | return iter; |
260 | } |
261 | |
262 | /* |
263 | * Return 0 on success, -1 on error |
264 | */ |
265 | extern int blkid_tag_next(blkid_tag_iterate iter, |
266 | const char **type, const char **value) |
267 | { |
268 | blkid_tag tag; |
269 | |
270 | *type = 0; |
271 | *value = 0; |
272 | if (!iter || iter->magic != TAG_ITERATE_MAGIC || |
273 | iter->p == &iter->dev->bid_tags) |
274 | return -1; |
275 | tag = list_entry(iter->p, struct blkid_struct_tag, bit_tags); |
276 | *type = tag->bit_name; |
277 | *value = tag->bit_val; |
278 | iter->p = iter->p->next; |
279 | return 0; |
280 | } |
281 | |
282 | void blkid_tag_iterate_end(blkid_tag_iterate iter) |
283 | { |
284 | if (!iter || iter->magic != TAG_ITERATE_MAGIC) |
285 | return; |
286 | iter->magic = 0; |
287 | free(iter); |
288 | } |
289 | |
290 | /* |
291 | * This function returns a device which matches a particular |
292 | * type/value pair. If there is more than one device that matches the |
293 | * search specification, it returns the one with the highest priority |
294 | * value. This allows us to give preference to EVMS or LVM devices. |
295 | * |
296 | * XXX there should also be an interface which uses an iterator so we |
297 | * can get all of the devices which match a type/value search parameter. |
298 | */ |
299 | extern blkid_dev blkid_find_dev_with_tag(blkid_cache cache, |
300 | const char *type, |
301 | const char *value) |
302 | { |
303 | blkid_tag head; |
304 | blkid_dev dev; |
305 | int pri; |
306 | struct list_head *p; |
307 | |
308 | if (!cache || !type || !value) |
309 | return NULL; |
310 | |
311 | blkid_read_cache(cache); |
312 | |
313 | DBG(DEBUG_TAG, printf("looking for %s=%s in cache\n", type, value)); |
314 | |
315 | try_again: |
316 | pri = -1; |
317 | dev = 0; |
318 | head = blkid_find_head_cache(cache, type); |
319 | |
320 | if (head) { |
321 | list_for_each(p, &head->bit_names) { |
322 | blkid_tag tmp = list_entry(p, struct blkid_struct_tag, |
323 | bit_names); |
324 | |
325 | if (!strcmp(tmp->bit_val, value) && |
326 | tmp->bit_dev->bid_pri > pri) { |
327 | dev = tmp->bit_dev; |
328 | pri = dev->bid_pri; |
329 | } |
330 | } |
331 | } |
332 | if (dev && !(dev->bid_flags & BLKID_BID_FL_VERIFIED)) { |
333 | dev = blkid_verify(cache, dev); |
334 | if (dev && (dev->bid_flags & BLKID_BID_FL_VERIFIED)) |
335 | goto try_again; |
336 | } |
337 | |
338 | if (!dev && !(cache->bic_flags & BLKID_BIC_FL_PROBED)) { |
339 | if (blkid_probe_all(cache) < 0) |
340 | return NULL; |
341 | goto try_again; |
342 | } |
343 | return dev; |
344 | } |
345 | |
346 | #ifdef TEST_PROGRAM |
347 | #ifdef HAVE_GETOPT_H |
348 | #include <getopt.h> |
349 | #else |
350 | extern char *optarg; |
351 | extern int optind; |
352 | #endif |
353 | |
354 | void usage(char *prog) |
355 | { |
356 | fprintf(stderr, "Usage: %s [-f blkid_file] [-m debug_mask] device " |
357 | "[type value]\n", |
358 | prog); |
359 | fprintf(stderr, "\tList all tags for a device and exit\n"); |
360 | exit(1); |
361 | } |
362 | |
363 | int main(int argc, char **argv) |
364 | { |
365 | blkid_tag_iterate iter; |
366 | blkid_cache cache = NULL; |
367 | blkid_dev dev; |
368 | int c, ret, found; |
369 | int flags = BLKID_DEV_FIND; |
370 | char *tmp; |
371 | char *file = NULL; |
372 | char *devname = NULL; |
373 | char *search_type = NULL; |
374 | char *search_value = NULL; |
375 | const char *type, *value; |
376 | |
377 | while ((c = getopt (argc, argv, "m:f:")) != EOF) |
378 | switch (c) { |
379 | case 'f': |
380 | file = optarg; |
381 | break; |
382 | case 'm': |
383 | blkid_debug_mask = strtoul (optarg, &tmp, 0); |
384 | if (*tmp) { |
385 | fprintf(stderr, "Invalid debug mask: %s\n", |
386 | optarg); |
387 | exit(1); |
388 | } |
389 | break; |
390 | case '?': |
391 | usage(argv[0]); |
392 | } |
393 | if (argc > optind) |
394 | devname = argv[optind++]; |
395 | if (argc > optind) |
396 | search_type = argv[optind++]; |
397 | if (argc > optind) |
398 | search_value = argv[optind++]; |
399 | if (!devname || (argc != optind)) |
400 | usage(argv[0]); |
401 | |
402 | if ((ret = blkid_get_cache(&cache, file)) != 0) { |
403 | fprintf(stderr, "%s: error creating cache (%d)\n", |
404 | argv[0], ret); |
405 | exit(1); |
406 | } |
407 | |
408 | dev = blkid_get_dev(cache, devname, flags); |
409 | if (!dev) { |
410 | fprintf(stderr, "%s: cannot find device in blkid cache\n", devname); |
411 | exit(1); |
412 | } |
413 | if (search_type) { |
414 | found = blkid_dev_has_tag(dev, search_type, search_value); |
415 | printf("Device %s: (%s, %s) %s\n", blkid_dev_devname(dev), |
416 | search_type, search_value ? search_value : "NULL", |
417 | found ? "FOUND" : "NOT FOUND"); |
418 | return !found; |
419 | } |
420 | printf("Device %s...\n", blkid_dev_devname(dev)); |
421 | |
422 | iter = blkid_tag_iterate_begin(dev); |
423 | while (blkid_tag_next(iter, &type, &value) == 0) { |
424 | printf("\tTag %s has value %s\n", type, value); |
425 | } |
426 | blkid_tag_iterate_end(iter); |
427 | |
428 | blkid_put_cache(cache); |
429 | return 0; |
430 | } |
431 | #endif |
432 |