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"
37 #include "glob-util.h"
41 #include "path-util.h"
42 #include "stat-util.h"
43 #include "string-util.h"
45 #include "time-util.h"
47 bool path_is_absolute(const char *p) {
51 bool is_path(const char *p) {
52 return !!strchr(p, '/');
55 #if 0 /// UNNEEDED by elogind
56 int path_split_and_make_absolute(const char *p, char ***ret) {
63 l = strv_split(p, ":");
67 r = path_strv_make_absolute_cwd(l);
77 char *path_make_absolute(const char *p, const char *prefix) {
80 /* Makes every item in the list an absolute path by prepending
81 * the prefix, if specified and necessary */
83 if (path_is_absolute(p) || !prefix)
86 return strjoin(prefix, "/", p, NULL);
90 int path_make_absolute_cwd(const char *p, char **ret) {
96 /* Similar to path_make_absolute(), but prefixes with the
97 * current working directory. */
99 if (path_is_absolute(p))
102 _cleanup_free_ char *cwd = NULL;
104 cwd = get_current_dir_name();
106 return negative_errno();
108 c = strjoin(cwd, "/", p, NULL);
117 #if 0 /// UNNEEDED by elogind
118 int path_make_relative(const char *from_dir, const char *to_path, char **_r) {
126 /* Strips the common part, and adds ".." elements as necessary. */
128 if (!path_is_absolute(from_dir))
131 if (!path_is_absolute(to_path))
134 /* Skip the common part. */
139 from_dir += strspn(from_dir, "/");
140 to_path += strspn(to_path, "/");
144 /* from_dir equals to_path. */
147 /* from_dir is a parent directory of to_path. */
153 path_kill_slashes(r);
162 a = strcspn(from_dir, "/");
163 b = strcspn(to_path, "/");
168 if (memcmp(from_dir, to_path, a) != 0)
175 /* If we're here, then "from_dir" has one or more elements that need to
176 * be replaced with "..". */
178 /* Count the number of necessary ".." elements. */
179 for (n_parents = 0;;) {
180 from_dir += strspn(from_dir, "/");
185 from_dir += strcspn(from_dir, "/");
189 r = malloc(n_parents * 3 + strlen(to_path) + 1);
193 for (p = r; n_parents > 0; n_parents--, p += 3)
197 path_kill_slashes(r);
203 int path_strv_make_absolute_cwd(char **l) {
207 /* Goes through every item in the string list and makes it
208 * absolute. This works in place and won't rollback any
209 * changes on failure. */
214 r = path_make_absolute_cwd(*s, &t);
226 char **path_strv_resolve(char **l, const char *prefix) {
234 /* Goes through every item in the string list and canonicalize
235 * the path. This works in place and won't rollback any
236 * changes on failure. */
240 _cleanup_free_ char *orig = NULL;
242 if (!path_is_absolute(*s)) {
249 t = strappend(prefix, orig);
258 u = canonicalize_file_name(t);
260 if (errno == ENOENT) {
269 if (errno == ENOMEM || errno == 0)
278 x = path_startswith(u, prefix);
280 /* restore the slash if it was lost */
281 if (!startswith(x, "/"))
292 /* canonicalized path goes outside of
293 * prefix, keep the original path instead */
294 free_and_replace(u, orig);
310 char **path_strv_resolve_uniq(char **l, const char *prefix) {
315 if (!path_strv_resolve(l, prefix))
321 char *path_kill_slashes(char *path) {
325 /* Removes redundant inner and trailing slashes. Modifies the
326 * passed string in-place.
328 * ///foo///bar/ becomes /foo/bar
331 for (f = path, t = path; *f; f++) {
346 /* Special rule, if we are talking of the root directory, a
347 trailing slash is good */
349 if (t == path && slash)
356 char* path_startswith(const char *path, const char *prefix) {
360 /* Returns a pointer to the start of the first component after the parts matched by
362 * - both paths are absolute or both paths are relative,
364 * - each component in prefix in turn matches a component in path at the same position.
365 * An empty string will be returned when the prefix and path are equivalent.
367 * Returns NULL otherwise.
370 if ((path[0] == '/') != (prefix[0] == '/'))
376 path += strspn(path, "/");
377 prefix += strspn(prefix, "/");
385 a = strcspn(path, "/");
386 b = strcspn(prefix, "/");
391 if (memcmp(path, prefix, a) != 0)
399 int path_compare(const char *a, const char *b) {
405 /* A relative path and an abolute path must not compare as equal.
406 * Which one is sorted before the other does not really matter.
407 * Here a relative path is ordered before an absolute path. */
408 d = (a[0] == '/') - (b[0] == '/');
418 if (*a == 0 && *b == 0)
421 /* Order prefixes first: "/foo" before "/foo/bar" */
430 /* Alphabetical sort: "/foo/aaa" before "/foo/b" */
431 d = memcmp(a, b, MIN(j, k));
433 return (d > 0) - (d < 0); /* sign of d */
435 /* Sort "/foo/a" before "/foo/aaa" */
436 d = (j > k) - (j < k); /* sign of (j - k) */
445 bool path_equal(const char *a, const char *b) {
446 return path_compare(a, b) == 0;
449 bool path_equal_or_files_same(const char *a, const char *b) {
450 return path_equal(a, b) || files_same(a, b) > 0;
453 #if 0 /// UNNEEDED by elogind
454 char* path_join(const char *root, const char *path, const char *rest) {
458 return strjoin(root, endswith(root, "/") ? "" : "/",
459 path[0] == '/' ? path+1 : path,
460 rest ? (endswith(path, "/") ? "" : "/") : NULL,
461 rest && rest[0] == '/' ? rest+1 : rest,
465 rest ? (endswith(path, "/") ? "" : "/") : NULL,
466 rest && rest[0] == '/' ? rest+1 : rest,
470 int find_binary(const char *name, char **ret) {
477 if (access(name, X_OK) < 0)
481 r = path_make_absolute_cwd(name, ret);
490 * Plain getenv, not secure_getenv, because we want
491 * to actually allow the user to pick the binary.
497 last_error = -ENOENT;
500 _cleanup_free_ char *j = NULL, *element = NULL;
502 r = extract_first_word(&p, &element, ":", EXTRACT_RELAX|EXTRACT_DONT_COALESCE_SEPARATORS);
508 if (!path_is_absolute(element))
511 j = strjoin(element, "/", name, NULL);
515 if (access(j, X_OK) >= 0) {
519 *ret = path_kill_slashes(j);
532 bool paths_check_timestamp(const char* const* paths, usec_t *timestamp, bool update) {
533 bool changed = false;
534 const char* const* i;
541 STRV_FOREACH(i, paths) {
545 if (stat(*i, &stats) < 0)
548 u = timespec_load(&stats.st_mtim);
554 log_debug("timestamp of '%s' changed", *i);
556 /* update timestamp */
567 static int binary_is_good(const char *binary) {
568 _cleanup_free_ char *p = NULL, *d = NULL;
571 r = find_binary(binary, &p);
577 /* An fsck that is linked to /bin/true is a non-existent
580 r = readlink_malloc(p, &d);
581 if (r == -EINVAL) /* not a symlink */
586 return !PATH_IN_SET(d, "true"
592 int fsck_exists(const char *fstype) {
597 if (streq(fstype, "auto"))
600 checker = strjoina("fsck.", fstype);
601 return binary_is_good(checker);
604 int mkfs_exists(const char *fstype) {
609 if (streq(fstype, "auto"))
612 mkfs = strjoina("mkfs.", fstype);
613 return binary_is_good(mkfs);
616 char *prefix_root(const char *root, const char *path) {
620 /* If root is passed, prefixes path with it. Otherwise returns
625 /* First, drop duplicate prefixing slashes from the path */
626 while (path[0] == '/' && path[1] == '/')
629 if (isempty(root) || path_equal(root, "/"))
632 l = strlen(root) + 1 + strlen(path) + 1;
640 while (p > n && p[-1] == '/')
650 int parse_path_argument_and_warn(const char *path, bool suppress_root, char **arg) {
655 * This function is intended to be used in command line
656 * parsers, to handle paths that are passed in. It makes the
657 * path absolute, and reduces it to NULL if omitted or
658 * root (the latter optionally).
660 * NOTE THAT THIS WILL FREE THE PREVIOUS ARGUMENT POINTER ON
661 * SUCCESS! Hence, do not pass in uninitialized pointers.
669 r = path_make_absolute_cwd(path, &p);
671 return log_error_errno(r, "Failed to parse path \"%s\" and make it absolute: %m", path);
673 path_kill_slashes(p);
674 if (suppress_root && path_equal(p, "/"))
683 char* dirname_malloc(const char *path) {
684 char *d, *dir, *dir2;
704 bool filename_is_valid(const char *p) {
716 e = strchrnul(p, '/');
720 if (e - p > FILENAME_MAX)
726 bool path_is_safe(const char *p) {
731 if (streq(p, "..") || startswith(p, "../") || endswith(p, "/..") || strstr(p, "/../"))
734 if (strlen(p)+1 > PATH_MAX)
737 /* The following two checks are not really dangerous, but hey, they still are confusing */
738 if (streq(p, ".") || startswith(p, "./") || endswith(p, "/.") || strstr(p, "/./"))
747 char *file_in_same_dir(const char *path, const char *filename) {
754 /* This removes the last component of path and appends
755 * filename, unless the latter is absolute anyway or the
758 if (path_is_absolute(filename))
759 return strdup(filename);
761 e = strrchr(path, '/');
763 return strdup(filename);
765 k = strlen(filename);
766 ret = new(char, (e + 1 - path) + k + 1);
770 memcpy(mempcpy(ret, path, e + 1 - path), filename, k + 1);
774 bool hidden_or_backup_file(const char *filename) {
779 if (filename[0] == '.' ||
780 streq(filename, "lost+found") ||
781 streq(filename, "aquota.user") ||
782 streq(filename, "aquota.group") ||
783 endswith(filename, "~"))
786 p = strrchr(filename, '.');
790 /* Please, let's not add more entries to the list below. If external projects think it's a good idea to come up
791 * with always new suffixes and that everybody else should just adjust to that, then it really should be on
792 * them. Hence, in future, let's not add any more entries. Instead, let's ask those packages to instead adopt
793 * one of the generic suffixes/prefixes for hidden files or backups, possibly augmented with an additional
794 * string. Specifically: there's now:
796 * The generic suffixes "~" and ".bak" for backup files
797 * The generic prefix "." for hidden files
799 * Thus, if a new package manager "foopkg" wants its own set of ".foopkg-new", ".foopkg-old", ".foopkg-dist"
800 * or so registered, let's refuse that and ask them to use ".foopkg.new", ".foopkg.old" or ".foopkg~" instead.
803 return STR_IN_SET(p + 1,
823 #if 0 /// UNNEEDED by elogind
824 bool is_device_path(const char *path) {
826 /* Returns true on paths that refer to a device, either in
827 * sysfs or in /dev */
829 return path_startswith(path, "/dev/") ||
830 path_startswith(path, "/sys/");
833 bool is_deviceallow_pattern(const char *path) {
834 return path_startswith(path, "/dev/") ||
835 startswith(path, "block-") ||
836 startswith(path, "char-");
840 int systemd_installation_has_version(const char *root, unsigned minimal_version) {
844 /* Try to guess if systemd installation is later than the specified version. This
845 * is hacky and likely to yield false negatives, particularly if the installation
846 * is non-standard. False positives should be relatively rare.
849 NULSTR_FOREACH(pattern,
850 /* /lib works for systems without usr-merge, and for systems with a sane
851 * usr-merge, where /lib is a symlink to /usr/lib. /usr/lib is necessary
852 * for Gentoo which does a merge without making /lib a symlink.
854 "lib/systemd/libsystemd-shared-*.so\0"
855 "usr/lib/systemd/libsystemd-shared-*.so\0") {
857 _cleanup_strv_free_ char **names = NULL;
858 _cleanup_free_ char *path = NULL;
861 path = prefix_root(root, pattern);
865 r = glob_extend(&names, path);
871 assert_se((c = endswith(path, "*.so")));
872 *c = '\0'; /* truncate the glob part */
874 STRV_FOREACH(name, names) {
875 /* This is most likely to run only once, hence let's not optimize anything. */
879 t = startswith(*name, path);
883 t2 = endswith(t, ".so");
887 t2[0] = '\0'; /* truncate the suffix */
889 r = safe_atou(t, &version);
891 log_debug_errno(r, "Found libsystemd shared at \"%s.so\", but failed to parse version: %m", *name);
895 log_debug("Found libsystemd shared at \"%s.so\", version %u (%s).",
897 version >= minimal_version ? "OK" : "too old");
898 if (version >= minimal_version)