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9eb977db KS |
1 | /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ |
2 | ||
3 | /*** | |
4 | This file is part of systemd. | |
5 | ||
6 | Copyright 2010-2012 Lennart Poettering | |
7 | ||
8 | systemd is free software; you can redistribute it and/or modify it | |
9 | under the terms of the GNU Lesser General Public License as published by | |
10 | the Free Software Foundation; either version 2.1 of the License, or | |
11 | (at your option) any later version. | |
12 | ||
13 | systemd is distributed in the hope that it will be useful, but | |
14 | WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
16 | Lesser General Public License for more details. | |
17 | ||
18 | You should have received a copy of the GNU Lesser General Public License | |
19 | along with systemd; If not, see <http://www.gnu.org/licenses/>. | |
20 | ***/ | |
21 | ||
22 | #include <assert.h> | |
23 | #include <string.h> | |
24 | #include <unistd.h> | |
25 | #include <errno.h> | |
26 | #include <stdlib.h> | |
27 | #include <signal.h> | |
28 | #include <stdio.h> | |
29 | #include <fcntl.h> | |
30 | #include <dirent.h> | |
31 | #include <sys/statvfs.h> | |
32 | ||
33 | #include "macro.h" | |
34 | #include "util.h" | |
35 | #include "log.h" | |
36 | #include "strv.h" | |
37 | #include "path-util.h" | |
a8348796 | 38 | #include "missing.h" |
9eb977db KS |
39 | |
40 | bool path_is_absolute(const char *p) { | |
41 | return p[0] == '/'; | |
42 | } | |
43 | ||
44 | bool is_path(const char *p) { | |
45 | return !!strchr(p, '/'); | |
46 | } | |
47 | ||
9eb977db KS |
48 | int path_get_parent(const char *path, char **_r) { |
49 | const char *e, *a = NULL, *b = NULL, *p; | |
50 | char *r; | |
51 | bool slash = false; | |
52 | ||
53 | assert(path); | |
54 | assert(_r); | |
55 | ||
56 | if (!*path) | |
57 | return -EINVAL; | |
58 | ||
59 | for (e = path; *e; e++) { | |
60 | ||
61 | if (!slash && *e == '/') { | |
62 | a = b; | |
63 | b = e; | |
64 | slash = true; | |
65 | } else if (slash && *e != '/') | |
66 | slash = false; | |
67 | } | |
68 | ||
69 | if (*(e-1) == '/') | |
70 | p = a; | |
71 | else | |
72 | p = b; | |
73 | ||
74 | if (!p) | |
75 | return -EINVAL; | |
76 | ||
77 | if (p == path) | |
78 | r = strdup("/"); | |
79 | else | |
80 | r = strndup(path, p-path); | |
81 | ||
82 | if (!r) | |
83 | return -ENOMEM; | |
84 | ||
85 | *_r = r; | |
86 | return 0; | |
87 | } | |
88 | ||
89 | char **path_split_and_make_absolute(const char *p) { | |
90 | char **l; | |
91 | assert(p); | |
92 | ||
116cc028 ZJS |
93 | l = strv_split(p, ":"); |
94 | if (!l) | |
9eb977db KS |
95 | return NULL; |
96 | ||
97 | if (!path_strv_make_absolute_cwd(l)) { | |
98 | strv_free(l); | |
99 | return NULL; | |
100 | } | |
101 | ||
102 | return l; | |
103 | } | |
104 | ||
105 | char *path_make_absolute(const char *p, const char *prefix) { | |
106 | assert(p); | |
107 | ||
108 | /* Makes every item in the list an absolute path by prepending | |
109 | * the prefix, if specified and necessary */ | |
110 | ||
111 | if (path_is_absolute(p) || !prefix) | |
112 | return strdup(p); | |
113 | ||
b7def684 | 114 | return strjoin(prefix, "/", p, NULL); |
9eb977db KS |
115 | } |
116 | ||
117 | char *path_make_absolute_cwd(const char *p) { | |
116cc028 | 118 | _cleanup_free_ char *cwd = NULL; |
9eb977db KS |
119 | |
120 | assert(p); | |
121 | ||
122 | /* Similar to path_make_absolute(), but prefixes with the | |
123 | * current working directory. */ | |
124 | ||
125 | if (path_is_absolute(p)) | |
126 | return strdup(p); | |
127 | ||
91a6489d LP |
128 | cwd = get_current_dir_name(); |
129 | if (!cwd) | |
9eb977db KS |
130 | return NULL; |
131 | ||
db594aef | 132 | return strjoin(cwd, "/", p, NULL); |
9eb977db KS |
133 | } |
134 | ||
7cb9c51c TK |
135 | int path_make_relative(const char *from_dir, const char *to_path, char **_r) { |
136 | char *r, *p; | |
137 | unsigned n_parents; | |
7cb9c51c TK |
138 | |
139 | assert(from_dir); | |
140 | assert(to_path); | |
141 | assert(_r); | |
142 | ||
143 | /* Strips the common part, and adds ".." elements as necessary. */ | |
144 | ||
145 | if (!path_is_absolute(from_dir)) | |
146 | return -EINVAL; | |
147 | ||
148 | if (!path_is_absolute(to_path)) | |
149 | return -EINVAL; | |
150 | ||
151 | /* Skip the common part. */ | |
152 | for (;;) { | |
153 | size_t a; | |
154 | size_t b; | |
155 | ||
156 | from_dir += strspn(from_dir, "/"); | |
157 | to_path += strspn(to_path, "/"); | |
158 | ||
159 | if (!*from_dir) { | |
160 | if (!*to_path) | |
161 | /* from_dir equals to_path. */ | |
162 | r = strdup("."); | |
163 | else | |
164 | /* from_dir is a parent directory of to_path. */ | |
165 | r = strdup(to_path); | |
166 | ||
167 | if (!r) | |
168 | return -ENOMEM; | |
169 | ||
5216f599 TK |
170 | path_kill_slashes(r); |
171 | ||
7cb9c51c TK |
172 | *_r = r; |
173 | return 0; | |
174 | } | |
175 | ||
176 | if (!*to_path) | |
177 | break; | |
178 | ||
179 | a = strcspn(from_dir, "/"); | |
180 | b = strcspn(to_path, "/"); | |
181 | ||
182 | if (a != b) | |
183 | break; | |
184 | ||
185 | if (memcmp(from_dir, to_path, a) != 0) | |
186 | break; | |
187 | ||
188 | from_dir += a; | |
189 | to_path += b; | |
190 | } | |
191 | ||
192 | /* If we're here, then "from_dir" has one or more elements that need to | |
193 | * be replaced with "..". */ | |
194 | ||
195 | /* Count the number of necessary ".." elements. */ | |
196 | for (n_parents = 0;;) { | |
197 | from_dir += strspn(from_dir, "/"); | |
198 | ||
199 | if (!*from_dir) | |
200 | break; | |
201 | ||
202 | from_dir += strcspn(from_dir, "/"); | |
203 | n_parents++; | |
204 | } | |
205 | ||
5216f599 | 206 | r = malloc(n_parents * 3 + strlen(to_path) + 1); |
7cb9c51c TK |
207 | if (!r) |
208 | return -ENOMEM; | |
209 | ||
210 | for (p = r; n_parents > 0; n_parents--, p += 3) | |
211 | memcpy(p, "../", 3); | |
212 | ||
5216f599 TK |
213 | strcpy(p, to_path); |
214 | path_kill_slashes(r); | |
7cb9c51c TK |
215 | |
216 | *_r = r; | |
217 | return 0; | |
218 | } | |
219 | ||
9eb977db KS |
220 | char **path_strv_make_absolute_cwd(char **l) { |
221 | char **s; | |
222 | ||
223 | /* Goes through every item in the string list and makes it | |
224 | * absolute. This works in place and won't rollback any | |
225 | * changes on failure. */ | |
226 | ||
227 | STRV_FOREACH(s, l) { | |
228 | char *t; | |
229 | ||
116cc028 ZJS |
230 | t = path_make_absolute_cwd(*s); |
231 | if (!t) | |
9eb977db KS |
232 | return NULL; |
233 | ||
234 | free(*s); | |
235 | *s = t; | |
236 | } | |
237 | ||
238 | return l; | |
239 | } | |
240 | ||
7d8da2c9 | 241 | char **path_strv_resolve(char **l, const char *prefix) { |
9eb977db KS |
242 | char **s; |
243 | unsigned k = 0; | |
244 | bool enomem = false; | |
245 | ||
246 | if (strv_isempty(l)) | |
247 | return l; | |
248 | ||
249 | /* Goes through every item in the string list and canonicalize | |
250 | * the path. This works in place and won't rollback any | |
251 | * changes on failure. */ | |
252 | ||
253 | STRV_FOREACH(s, l) { | |
254 | char *t, *u; | |
12ed81d9 | 255 | _cleanup_free_ char *orig = NULL; |
9eb977db | 256 | |
12ed81d9 ZJS |
257 | if (!path_is_absolute(*s)) { |
258 | free(*s); | |
9eb977db | 259 | continue; |
12ed81d9 | 260 | } |
112cfb18 MM |
261 | |
262 | if (prefix) { | |
12ed81d9 ZJS |
263 | orig = *s; |
264 | t = strappend(prefix, orig); | |
112cfb18 MM |
265 | if (!t) { |
266 | enomem = true; | |
267 | continue; | |
268 | } | |
12ed81d9 | 269 | } else |
112cfb18 | 270 | t = *s; |
9eb977db KS |
271 | |
272 | errno = 0; | |
273 | u = canonicalize_file_name(t); | |
9eb977db | 274 | if (!u) { |
12ed81d9 ZJS |
275 | if (errno == ENOENT) { |
276 | if (prefix) { | |
277 | u = orig; | |
278 | orig = NULL; | |
279 | free(t); | |
280 | } else | |
281 | u = t; | |
282 | } else { | |
874310b7 | 283 | free(t); |
112cfb18 | 284 | if (errno == ENOMEM || errno == 0) |
874310b7 ZJS |
285 | enomem = true; |
286 | ||
287 | continue; | |
288 | } | |
12ed81d9 ZJS |
289 | } else if (prefix) { |
290 | char *x; | |
291 | ||
292 | free(t); | |
293 | x = path_startswith(u, prefix); | |
294 | if (x) { | |
295 | /* restore the slash if it was lost */ | |
296 | if (!startswith(x, "/")) | |
297 | *(--x) = '/'; | |
298 | ||
299 | t = strdup(x); | |
300 | free(u); | |
301 | if (!t) { | |
302 | enomem = true; | |
303 | continue; | |
304 | } | |
305 | u = t; | |
306 | } else { | |
307 | /* canonicalized path goes outside of | |
308 | * prefix, keep the original path instead */ | |
3542eac7 | 309 | free(u); |
12ed81d9 ZJS |
310 | u = orig; |
311 | orig = NULL; | |
312 | } | |
91a6489d LP |
313 | } else |
314 | free(t); | |
9eb977db KS |
315 | |
316 | l[k++] = u; | |
317 | } | |
318 | ||
319 | l[k] = NULL; | |
320 | ||
321 | if (enomem) | |
322 | return NULL; | |
323 | ||
324 | return l; | |
325 | } | |
326 | ||
7d8da2c9 | 327 | char **path_strv_resolve_uniq(char **l, const char *prefix) { |
112cfb18 | 328 | |
fabe5c0e LP |
329 | if (strv_isempty(l)) |
330 | return l; | |
331 | ||
7d8da2c9 | 332 | if (!path_strv_resolve(l, prefix)) |
fabe5c0e LP |
333 | return NULL; |
334 | ||
335 | return strv_uniq(l); | |
336 | } | |
337 | ||
9eb977db KS |
338 | char *path_kill_slashes(char *path) { |
339 | char *f, *t; | |
340 | bool slash = false; | |
341 | ||
342 | /* Removes redundant inner and trailing slashes. Modifies the | |
343 | * passed string in-place. | |
344 | * | |
345 | * ///foo///bar/ becomes /foo/bar | |
346 | */ | |
347 | ||
348 | for (f = path, t = path; *f; f++) { | |
349 | ||
350 | if (*f == '/') { | |
351 | slash = true; | |
352 | continue; | |
353 | } | |
354 | ||
355 | if (slash) { | |
356 | slash = false; | |
357 | *(t++) = '/'; | |
358 | } | |
359 | ||
360 | *(t++) = *f; | |
361 | } | |
362 | ||
363 | /* Special rule, if we are talking of the root directory, a | |
364 | trailing slash is good */ | |
365 | ||
366 | if (t == path && slash) | |
367 | *(t++) = '/'; | |
368 | ||
369 | *t = 0; | |
370 | return path; | |
371 | } | |
372 | ||
424a19f8 | 373 | char* path_startswith(const char *path, const char *prefix) { |
9eb977db KS |
374 | assert(path); |
375 | assert(prefix); | |
376 | ||
377 | if ((path[0] == '/') != (prefix[0] == '/')) | |
424a19f8 | 378 | return NULL; |
9eb977db KS |
379 | |
380 | for (;;) { | |
381 | size_t a, b; | |
382 | ||
383 | path += strspn(path, "/"); | |
384 | prefix += strspn(prefix, "/"); | |
385 | ||
386 | if (*prefix == 0) | |
424a19f8 | 387 | return (char*) path; |
9eb977db KS |
388 | |
389 | if (*path == 0) | |
424a19f8 | 390 | return NULL; |
9eb977db KS |
391 | |
392 | a = strcspn(path, "/"); | |
393 | b = strcspn(prefix, "/"); | |
394 | ||
395 | if (a != b) | |
424a19f8 | 396 | return NULL; |
9eb977db KS |
397 | |
398 | if (memcmp(path, prefix, a) != 0) | |
424a19f8 | 399 | return NULL; |
9eb977db KS |
400 | |
401 | path += a; | |
402 | prefix += b; | |
403 | } | |
404 | } | |
405 | ||
406 | bool path_equal(const char *a, const char *b) { | |
407 | assert(a); | |
408 | assert(b); | |
409 | ||
410 | if ((a[0] == '/') != (b[0] == '/')) | |
411 | return false; | |
412 | ||
413 | for (;;) { | |
414 | size_t j, k; | |
415 | ||
416 | a += strspn(a, "/"); | |
417 | b += strspn(b, "/"); | |
418 | ||
419 | if (*a == 0 && *b == 0) | |
420 | return true; | |
421 | ||
422 | if (*a == 0 || *b == 0) | |
423 | return false; | |
424 | ||
425 | j = strcspn(a, "/"); | |
426 | k = strcspn(b, "/"); | |
427 | ||
428 | if (j != k) | |
429 | return false; | |
430 | ||
431 | if (memcmp(a, b, j) != 0) | |
432 | return false; | |
433 | ||
434 | a += j; | |
435 | b += k; | |
436 | } | |
437 | } | |
438 | ||
0c6ea3a4 ZJS |
439 | char* path_join(const char *root, const char *path, const char *rest) { |
440 | assert(path); | |
441 | ||
442 | if (!isempty(root)) | |
bc854dc7 | 443 | return strjoin(root, endswith(root, "/") ? "" : "/", |
0c6ea3a4 | 444 | path[0] == '/' ? path+1 : path, |
bc854dc7 | 445 | rest ? (endswith(path, "/") ? "" : "/") : NULL, |
0c6ea3a4 ZJS |
446 | rest && rest[0] == '/' ? rest+1 : rest, |
447 | NULL); | |
448 | else | |
449 | return strjoin(path, | |
bc854dc7 | 450 | rest ? (endswith(path, "/") ? "" : "/") : NULL, |
0c6ea3a4 ZJS |
451 | rest && rest[0] == '/' ? rest+1 : rest, |
452 | NULL); | |
453 | } | |
454 | ||
9eb977db | 455 | int path_is_mount_point(const char *t, bool allow_symlink) { |
21749924 | 456 | |
2695c5c4 | 457 | union file_handle_union h = FILE_HANDLE_INIT; |
e40872fc | 458 | int mount_id = -1, mount_id_parent = -1; |
e1d75803 | 459 | _cleanup_free_ char *parent = NULL; |
1640a0b6 | 460 | struct stat a, b; |
21749924 | 461 | int r; |
6feeeab0 | 462 | bool nosupp = false; |
9eb977db | 463 | |
cde9cb34 LP |
464 | /* We are not actually interested in the file handles, but |
465 | * name_to_handle_at() also passes us the mount ID, hence use | |
466 | * it but throw the handle away */ | |
467 | ||
468 | if (path_equal(t, "/")) | |
469 | return 1; | |
9eb977db | 470 | |
21749924 | 471 | r = name_to_handle_at(AT_FDCWD, t, &h.handle, &mount_id, allow_symlink ? AT_SYMLINK_FOLLOW : 0); |
9eb977db | 472 | if (r < 0) { |
e40872fc DR |
473 | if (errno == ENOSYS) |
474 | /* This kernel does not support name_to_handle_at() | |
475 | * fall back to the traditional stat() logic. */ | |
476 | goto fallback; | |
477 | else if (errno == EOPNOTSUPP) | |
fa125f4e | 478 | /* This kernel or file system does not support |
1640a0b6 LP |
479 | * name_to_handle_at(), hence fallback to the |
480 | * traditional stat() logic */ | |
6feeeab0 ZJS |
481 | nosupp = true; |
482 | else if (errno == ENOENT) | |
9eb977db | 483 | return 0; |
6feeeab0 ZJS |
484 | else |
485 | return -errno; | |
9eb977db KS |
486 | } |
487 | ||
488 | r = path_get_parent(t, &parent); | |
489 | if (r < 0) | |
490 | return r; | |
491 | ||
21749924 | 492 | h.handle.handle_bytes = MAX_HANDLE_SZ; |
b890bf6a | 493 | r = name_to_handle_at(AT_FDCWD, parent, &h.handle, &mount_id_parent, AT_SYMLINK_FOLLOW); |
6feeeab0 | 494 | if (r < 0) |
21749924 | 495 | if (errno == EOPNOTSUPP) |
6feeeab0 ZJS |
496 | if (nosupp) |
497 | /* Neither parent nor child do name_to_handle_at()? | |
498 | We have no choice but to fall back. */ | |
499 | goto fallback; | |
500 | else | |
501 | /* The parent can't do name_to_handle_at() but | |
502 | * the directory we are interested in can? | |
503 | * Or the other way around? | |
504 | * If so, it must be a mount point. */ | |
505 | return 1; | |
506 | else | |
507 | return -errno; | |
508 | else | |
509 | return mount_id != mount_id_parent; | |
1640a0b6 LP |
510 | |
511 | fallback: | |
512 | if (allow_symlink) | |
513 | r = stat(t, &a); | |
514 | else | |
f408b8f1 | 515 | r = lstat(t, &a); |
1640a0b6 | 516 | |
8ac75493 MM |
517 | if (r < 0) { |
518 | if (errno == ENOENT) | |
519 | return 0; | |
520 | ||
9eb977db | 521 | return -errno; |
8ac75493 | 522 | } |
9eb977db | 523 | |
a0539d77 TG |
524 | free(parent); |
525 | parent = NULL; | |
526 | ||
1640a0b6 LP |
527 | r = path_get_parent(t, &parent); |
528 | if (r < 0) | |
529 | return r; | |
cde9cb34 | 530 | |
c0e57ba9 | 531 | r = stat(parent, &b); |
1640a0b6 LP |
532 | if (r < 0) |
533 | return -errno; | |
534 | ||
535 | return a.st_dev != b.st_dev; | |
9eb977db KS |
536 | } |
537 | ||
538 | int path_is_read_only_fs(const char *path) { | |
539 | struct statvfs st; | |
540 | ||
541 | assert(path); | |
542 | ||
543 | if (statvfs(path, &st) < 0) | |
544 | return -errno; | |
545 | ||
70421bdc LP |
546 | if (st.f_flag & ST_RDONLY) |
547 | return true; | |
548 | ||
549 | /* On NFS, statvfs() might not reflect whether we can actually | |
550 | * write to the remote share. Let's try again with | |
551 | * access(W_OK) which is more reliable, at least sometimes. */ | |
552 | if (access(path, W_OK) < 0 && errno == EROFS) | |
553 | return true; | |
554 | ||
555 | return false; | |
9eb977db | 556 | } |
66060897 LP |
557 | |
558 | int path_is_os_tree(const char *path) { | |
559 | char *p; | |
560 | int r; | |
561 | ||
5ae4d543 LP |
562 | /* We use /usr/lib/os-release as flag file if something is an OS */ |
563 | p = strappenda(path, "/usr/lib/os-release"); | |
564 | r = access(p, F_OK); | |
565 | ||
566 | if (r >= 0) | |
567 | return 1; | |
66060897 | 568 | |
5ae4d543 | 569 | /* Also check for the old location in /etc, just in case. */ |
66060897 LP |
570 | p = strappenda(path, "/etc/os-release"); |
571 | r = access(p, F_OK); | |
572 | ||
5ae4d543 | 573 | return r >= 0; |
66060897 | 574 | } |
c9d954b2 | 575 | |
b63bd109 | 576 | int find_binary(const char *name, bool local, char **filename) { |
c9d954b2 | 577 | assert(name); |
4087cb9e | 578 | |
571d0134 | 579 | if (is_path(name)) { |
b63bd109 | 580 | if (local && access(name, X_OK) < 0) |
b972115c ZJS |
581 | return -errno; |
582 | ||
eb66db55 MG |
583 | if (filename) { |
584 | char *p; | |
c9d954b2 | 585 | |
b972115c | 586 | p = path_make_absolute_cwd(name); |
eb66db55 MG |
587 | if (!p) |
588 | return -ENOMEM; | |
b972115c | 589 | |
eb66db55 MG |
590 | *filename = p; |
591 | } | |
c9d954b2 | 592 | |
c9d954b2 ZJS |
593 | return 0; |
594 | } else { | |
595 | const char *path; | |
a2a5291b | 596 | const char *word, *state; |
c9d954b2 ZJS |
597 | size_t l; |
598 | ||
599 | /** | |
600 | * Plain getenv, not secure_getenv, because we want | |
601 | * to actually allow the user to pick the binary. | |
602 | */ | |
603 | path = getenv("PATH"); | |
604 | if (!path) | |
605 | path = DEFAULT_PATH; | |
606 | ||
a2a5291b | 607 | FOREACH_WORD_SEPARATOR(word, l, path, ":", state) { |
eb66db55 | 608 | _cleanup_free_ char *p = NULL; |
c9d954b2 | 609 | |
a2a5291b | 610 | if (asprintf(&p, "%.*s/%s", (int) l, word, name) < 0) |
c9d954b2 ZJS |
611 | return -ENOMEM; |
612 | ||
eb66db55 | 613 | if (access(p, X_OK) < 0) |
c9d954b2 | 614 | continue; |
c9d954b2 | 615 | |
eb66db55 | 616 | if (filename) { |
dbb9401d | 617 | *filename = path_kill_slashes(p); |
eb66db55 MG |
618 | p = NULL; |
619 | } | |
c9d954b2 ZJS |
620 | |
621 | return 0; | |
622 | } | |
623 | ||
624 | return -ENOENT; | |
625 | } | |
626 | } | |
8e184852 | 627 | |
2ad8416d | 628 | bool paths_check_timestamp(const char* const* paths, usec_t *timestamp, bool update) { |
8e184852 | 629 | bool changed = false; |
2ad8416d | 630 | const char* const* i; |
8e184852 | 631 | |
97f2d76d TG |
632 | assert(timestamp); |
633 | ||
8e184852 | 634 | if (paths == NULL) |
4087cb9e | 635 | return false; |
8e184852 | 636 | |
4087cb9e | 637 | STRV_FOREACH(i, paths) { |
8e184852 | 638 | struct stat stats; |
4087cb9e | 639 | usec_t u; |
8e184852 | 640 | |
4087cb9e | 641 | if (stat(*i, &stats) < 0) |
8e184852 TG |
642 | continue; |
643 | ||
4087cb9e LP |
644 | u = timespec_load(&stats.st_mtim); |
645 | ||
97f2d76d | 646 | /* first check */ |
4087cb9e | 647 | if (*timestamp >= u) |
8e184852 TG |
648 | continue; |
649 | ||
9f6445e3 | 650 | log_debug("timestamp of '%s' changed", *i); |
8e184852 TG |
651 | |
652 | /* update timestamp */ | |
4087cb9e LP |
653 | if (update) { |
654 | *timestamp = u; | |
655 | changed = true; | |
656 | } else | |
657 | return true; | |
8e184852 | 658 | } |
4087cb9e | 659 | |
8e184852 TG |
660 | return changed; |
661 | } | |
eb66db55 MG |
662 | |
663 | int fsck_exists(const char *fstype) { | |
571d0134 | 664 | _cleanup_free_ char *p = NULL, *d = NULL; |
eb66db55 | 665 | const char *checker; |
571d0134 | 666 | int r; |
eb66db55 MG |
667 | |
668 | checker = strappenda("fsck.", fstype); | |
571d0134 | 669 | |
b63bd109 | 670 | r = find_binary(checker, true, &p); |
571d0134 LP |
671 | if (r < 0) |
672 | return r; | |
673 | ||
061df014 | 674 | /* An fsck that is linked to /bin/true is a non-existent |
571d0134 LP |
675 | * fsck */ |
676 | ||
677 | r = readlink_malloc(p, &d); | |
678 | if (r >= 0 && | |
679 | (path_equal(d, "/bin/true") || | |
680 | path_equal(d, "/usr/bin/true") || | |
681 | path_equal(d, "/dev/null"))) | |
682 | return -ENOENT; | |
683 | ||
684 | return 0; | |
eb66db55 | 685 | } |