2 This file is part of systemd.
4 Copyright 2010-2012 Lennart Poettering
6 systemd is free software; you can redistribute it and/or modify it
7 under the terms of the GNU Lesser General Public License as published by
8 the Free Software Foundation; either version 2.1 of the License, or
9 (at your option) any later version.
11 systemd is distributed in the hope that it will be useful, but
12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public License
17 along with systemd; If not, see <http://www.gnu.org/licenses/>.
28 /* When we include libgen.h because we need dirname() we immediately
29 * undefine basename() since libgen.h defines it as a macro to the
30 * POSIX version which is really broken. We prefer GNU basename(). */
34 #include "alloc-util.h"
35 #include "extract-word.h"
40 #include "path-util.h"
41 #include "stat-util.h"
42 #include "string-util.h"
44 #include "time-util.h"
46 bool path_is_absolute(const char *p) {
50 bool is_path(const char *p) {
51 return !!strchr(p, '/');
54 #if 0 /// UNNEEDED by elogind
55 int path_split_and_make_absolute(const char *p, char ***ret) {
62 l = strv_split(p, ":");
66 r = path_strv_make_absolute_cwd(l);
76 char *path_make_absolute(const char *p, const char *prefix) {
79 /* Makes every item in the list an absolute path by prepending
80 * the prefix, if specified and necessary */
82 if (path_is_absolute(p) || !prefix)
85 return strjoin(prefix, "/", p, NULL);
89 int path_make_absolute_cwd(const char *p, char **ret) {
95 /* Similar to path_make_absolute(), but prefixes with the
96 * current working directory. */
98 if (path_is_absolute(p))
101 _cleanup_free_ char *cwd = NULL;
103 cwd = get_current_dir_name();
105 return negative_errno();
107 c = strjoin(cwd, "/", p, NULL);
116 #if 0 /// UNNEEDED by elogind
117 int path_make_relative(const char *from_dir, const char *to_path, char **_r) {
125 /* Strips the common part, and adds ".." elements as necessary. */
127 if (!path_is_absolute(from_dir))
130 if (!path_is_absolute(to_path))
133 /* Skip the common part. */
138 from_dir += strspn(from_dir, "/");
139 to_path += strspn(to_path, "/");
143 /* from_dir equals to_path. */
146 /* from_dir is a parent directory of to_path. */
152 path_kill_slashes(r);
161 a = strcspn(from_dir, "/");
162 b = strcspn(to_path, "/");
167 if (memcmp(from_dir, to_path, a) != 0)
174 /* If we're here, then "from_dir" has one or more elements that need to
175 * be replaced with "..". */
177 /* Count the number of necessary ".." elements. */
178 for (n_parents = 0;;) {
179 from_dir += strspn(from_dir, "/");
184 from_dir += strcspn(from_dir, "/");
188 r = malloc(n_parents * 3 + strlen(to_path) + 1);
192 for (p = r; n_parents > 0; n_parents--, p += 3)
196 path_kill_slashes(r);
202 int path_strv_make_absolute_cwd(char **l) {
206 /* Goes through every item in the string list and makes it
207 * absolute. This works in place and won't rollback any
208 * changes on failure. */
213 r = path_make_absolute_cwd(*s, &t);
225 char **path_strv_resolve(char **l, const char *prefix) {
233 /* Goes through every item in the string list and canonicalize
234 * the path. This works in place and won't rollback any
235 * changes on failure. */
239 _cleanup_free_ char *orig = NULL;
241 if (!path_is_absolute(*s)) {
248 t = strappend(prefix, orig);
257 u = canonicalize_file_name(t);
259 if (errno == ENOENT) {
268 if (errno == ENOMEM || errno == 0)
277 x = path_startswith(u, prefix);
279 /* restore the slash if it was lost */
280 if (!startswith(x, "/"))
291 /* canonicalized path goes outside of
292 * prefix, keep the original path instead */
311 char **path_strv_resolve_uniq(char **l, const char *prefix) {
316 if (!path_strv_resolve(l, prefix))
322 char *path_kill_slashes(char *path) {
326 /* Removes redundant inner and trailing slashes. Modifies the
327 * passed string in-place.
329 * ///foo///bar/ becomes /foo/bar
332 for (f = path, t = path; *f; f++) {
347 /* Special rule, if we are talking of the root directory, a
348 trailing slash is good */
350 if (t == path && slash)
357 char* path_startswith(const char *path, const char *prefix) {
361 if ((path[0] == '/') != (prefix[0] == '/'))
367 path += strspn(path, "/");
368 prefix += strspn(prefix, "/");
376 a = strcspn(path, "/");
377 b = strcspn(prefix, "/");
382 if (memcmp(path, prefix, a) != 0)
390 int path_compare(const char *a, const char *b) {
396 /* A relative path and an abolute path must not compare as equal.
397 * Which one is sorted before the other does not really matter.
398 * Here a relative path is ordered before an absolute path. */
399 d = (a[0] == '/') - (b[0] == '/');
409 if (*a == 0 && *b == 0)
412 /* Order prefixes first: "/foo" before "/foo/bar" */
421 /* Alphabetical sort: "/foo/aaa" before "/foo/b" */
422 d = memcmp(a, b, MIN(j, k));
424 return (d > 0) - (d < 0); /* sign of d */
426 /* Sort "/foo/a" before "/foo/aaa" */
427 d = (j > k) - (j < k); /* sign of (j - k) */
436 bool path_equal(const char *a, const char *b) {
437 return path_compare(a, b) == 0;
440 bool path_equal_or_files_same(const char *a, const char *b) {
441 return path_equal(a, b) || files_same(a, b) > 0;
444 #if 0 /// UNNEEDED by elogind
445 char* path_join(const char *root, const char *path, const char *rest) {
449 return strjoin(root, endswith(root, "/") ? "" : "/",
450 path[0] == '/' ? path+1 : path,
451 rest ? (endswith(path, "/") ? "" : "/") : NULL,
452 rest && rest[0] == '/' ? rest+1 : rest,
456 rest ? (endswith(path, "/") ? "" : "/") : NULL,
457 rest && rest[0] == '/' ? rest+1 : rest,
461 int find_binary(const char *name, char **ret) {
468 if (access(name, X_OK) < 0)
472 r = path_make_absolute_cwd(name, ret);
481 * Plain getenv, not secure_getenv, because we want
482 * to actually allow the user to pick the binary.
488 last_error = -ENOENT;
491 _cleanup_free_ char *j = NULL, *element = NULL;
493 r = extract_first_word(&p, &element, ":", EXTRACT_RELAX|EXTRACT_DONT_COALESCE_SEPARATORS);
499 if (!path_is_absolute(element))
502 j = strjoin(element, "/", name, NULL);
506 if (access(j, X_OK) >= 0) {
510 *ret = path_kill_slashes(j);
523 bool paths_check_timestamp(const char* const* paths, usec_t *timestamp, bool update) {
524 bool changed = false;
525 const char* const* i;
532 STRV_FOREACH(i, paths) {
536 if (stat(*i, &stats) < 0)
539 u = timespec_load(&stats.st_mtim);
545 log_debug("timestamp of '%s' changed", *i);
547 /* update timestamp */
558 static int binary_is_good(const char *binary) {
559 _cleanup_free_ char *p = NULL, *d = NULL;
562 r = find_binary(binary, &p);
568 /* An fsck that is linked to /bin/true is a non-existent
571 r = readlink_malloc(p, &d);
572 if (r == -EINVAL) /* not a symlink */
577 return !PATH_IN_SET(d, "true"
583 int fsck_exists(const char *fstype) {
588 if (streq(fstype, "auto"))
591 checker = strjoina("fsck.", fstype);
592 return binary_is_good(checker);
595 int mkfs_exists(const char *fstype) {
600 if (streq(fstype, "auto"))
603 mkfs = strjoina("mkfs.", fstype);
604 return binary_is_good(mkfs);
607 char *prefix_root(const char *root, const char *path) {
611 /* If root is passed, prefixes path with it. Otherwise returns
616 /* First, drop duplicate prefixing slashes from the path */
617 while (path[0] == '/' && path[1] == '/')
620 if (isempty(root) || path_equal(root, "/"))
623 l = strlen(root) + 1 + strlen(path) + 1;
631 while (p > n && p[-1] == '/')
641 int parse_path_argument_and_warn(const char *path, bool suppress_root, char **arg) {
646 * This function is intended to be used in command line
647 * parsers, to handle paths that are passed in. It makes the
648 * path absolute, and reduces it to NULL if omitted or
649 * root (the latter optionally).
651 * NOTE THAT THIS WILL FREE THE PREVIOUS ARGUMENT POINTER ON
652 * SUCCESS! Hence, do not pass in uninitialized pointers.
660 r = path_make_absolute_cwd(path, &p);
662 return log_error_errno(r, "Failed to parse path \"%s\" and make it absolute: %m", path);
664 path_kill_slashes(p);
665 if (suppress_root && path_equal(p, "/"))
674 char* dirname_malloc(const char *path) {
675 char *d, *dir, *dir2;
695 bool filename_is_valid(const char *p) {
707 e = strchrnul(p, '/');
711 if (e - p > FILENAME_MAX)
717 bool path_is_safe(const char *p) {
722 if (streq(p, "..") || startswith(p, "../") || endswith(p, "/..") || strstr(p, "/../"))
725 if (strlen(p)+1 > PATH_MAX)
728 /* The following two checks are not really dangerous, but hey, they still are confusing */
729 if (streq(p, ".") || startswith(p, "./") || endswith(p, "/.") || strstr(p, "/./"))
738 char *file_in_same_dir(const char *path, const char *filename) {
745 /* This removes the last component of path and appends
746 * filename, unless the latter is absolute anyway or the
749 if (path_is_absolute(filename))
750 return strdup(filename);
752 e = strrchr(path, '/');
754 return strdup(filename);
756 k = strlen(filename);
757 ret = new(char, (e + 1 - path) + k + 1);
761 memcpy(mempcpy(ret, path, e + 1 - path), filename, k + 1);
765 bool hidden_or_backup_file(const char *filename) {
770 if (filename[0] == '.' ||
771 streq(filename, "lost+found") ||
772 streq(filename, "aquota.user") ||
773 streq(filename, "aquota.group") ||
774 endswith(filename, "~"))
777 p = strrchr(filename, '.');
781 /* Please, let's not add more entries to the list below. If external projects think it's a good idea to come up
782 * with always new suffixes and that everybody else should just adjust to that, then it really should be on
783 * them. Hence, in future, let's not add any more entries. Instead, let's ask those packages to instead adopt
784 * one of the generic suffixes/prefixes for hidden files or backups, possibly augmented with an additional
785 * string. Specifically: there's now:
787 * The generic suffixes "~" and ".bak" for backup files
788 * The generic prefix "." for hidden files
790 * Thus, if a new package manager "foopkg" wants its own set of ".foopkg-new", ".foopkg-old", ".foopkg-dist"
791 * or so registered, let's refuse that and ask them to use ".foopkg.new", ".foopkg.old" or ".foopkg~" instead.
794 return STR_IN_SET(p + 1,
814 #if 0 /// UNNEEDED by elogind
815 bool is_device_path(const char *path) {
817 /* Returns true on paths that refer to a device, either in
818 * sysfs or in /dev */
821 path_startswith(path, "/dev/") ||
822 path_startswith(path, "/sys/");