1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2010-2012 Lennart Poettering
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.
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.
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/>.
31 #include <sys/statvfs.h>
37 #include "path-util.h"
40 bool path_is_absolute(const char *p) {
44 bool is_path(const char *p) {
45 return !!strchr(p, '/');
48 int path_get_parent(const char *path, char **_r) {
49 const char *e, *a = NULL, *b = NULL, *p;
59 for (e = path; *e; e++) {
61 if (!slash && *e == '/') {
65 } else if (slash && *e != '/')
80 r = strndup(path, p-path);
89 char **path_split_and_make_absolute(const char *p) {
93 l = strv_split(p, ":");
97 if (!path_strv_make_absolute_cwd(l)) {
105 char *path_make_absolute(const char *p, const char *prefix) {
108 /* Makes every item in the list an absolute path by prepending
109 * the prefix, if specified and necessary */
111 if (path_is_absolute(p) || !prefix)
114 return strjoin(prefix, "/", p, NULL);
117 char *path_make_absolute_cwd(const char *p) {
118 _cleanup_free_ char *cwd = NULL;
122 /* Similar to path_make_absolute(), but prefixes with the
123 * current working directory. */
125 if (path_is_absolute(p))
128 cwd = get_current_dir_name();
132 return path_make_absolute(p, cwd);
135 char **path_strv_make_absolute_cwd(char **l) {
138 /* Goes through every item in the string list and makes it
139 * absolute. This works in place and won't rollback any
140 * changes on failure. */
145 t = path_make_absolute_cwd(*s);
156 char **path_strv_canonicalize_absolute(char **l, const char *prefix) {
164 /* Goes through every item in the string list and canonicalize
165 * the path. This works in place and won't rollback any
166 * changes on failure. */
171 if (!path_is_absolute(*s))
175 t = strappend(prefix, *s);
189 u = canonicalize_file_name(t);
195 if (errno == ENOMEM || errno == 0)
214 char **path_strv_canonicalize_absolute_uniq(char **l, const char *prefix) {
219 if (!path_strv_canonicalize_absolute(l, prefix))
225 char *path_kill_slashes(char *path) {
229 /* Removes redundant inner and trailing slashes. Modifies the
230 * passed string in-place.
232 * ///foo///bar/ becomes /foo/bar
235 for (f = path, t = path; *f; f++) {
250 /* Special rule, if we are talking of the root directory, a
251 trailing slash is good */
253 if (t == path && slash)
260 char* path_startswith(const char *path, const char *prefix) {
264 if ((path[0] == '/') != (prefix[0] == '/'))
270 path += strspn(path, "/");
271 prefix += strspn(prefix, "/");
279 a = strcspn(path, "/");
280 b = strcspn(prefix, "/");
285 if (memcmp(path, prefix, a) != 0)
293 bool path_equal(const char *a, const char *b) {
297 if ((a[0] == '/') != (b[0] == '/'))
306 if (*a == 0 && *b == 0)
309 if (*a == 0 || *b == 0)
318 if (memcmp(a, b, j) != 0)
326 int path_is_mount_point(const char *t, bool allow_symlink) {
328 union file_handle_union h = {
329 .handle.handle_bytes = MAX_HANDLE_SZ
332 int mount_id, mount_id_parent;
337 /* We are not actually interested in the file handles, but
338 * name_to_handle_at() also passes us the mount ID, hence use
339 * it but throw the handle away */
341 if (path_equal(t, "/"))
344 r = name_to_handle_at(AT_FDCWD, t, &h.handle, &mount_id, allow_symlink ? AT_SYMLINK_FOLLOW : 0);
346 if (IN_SET(errno, ENOSYS, EOPNOTSUPP))
347 /* This kernel or file system does not support
348 * name_to_handle_at(), hence fallback to the
349 * traditional stat() logic */
358 r = path_get_parent(t, &parent);
362 h.handle.handle_bytes = MAX_HANDLE_SZ;
363 r = name_to_handle_at(AT_FDCWD, parent, &h.handle, &mount_id_parent, 0);
366 /* The parent can't do name_to_handle_at() but the
367 * directory we are interested in can? If so, it must
368 * be a mount point */
369 if (errno == EOPNOTSUPP)
375 return mount_id != mount_id_parent;
390 r = path_get_parent(t, &parent);
394 r = lstat(parent, &b);
399 return a.st_dev != b.st_dev;
402 int path_is_read_only_fs(const char *path) {
407 if (statvfs(path, &st) < 0)
410 return !!(st.f_flag & ST_RDONLY);
413 int path_is_os_tree(const char *path) {
417 /* We use /etc/os-release as flag file if something is an OS */
419 p = strappenda(path, "/etc/os-release");
422 return r < 0 ? 0 : 1;
425 int find_binary(const char *name, char **filename) {
428 if (strchr(name, '/')) {
429 if (access(name, X_OK) < 0)
435 p = path_make_absolute_cwd(name);
449 * Plain getenv, not secure_getenv, because we want
450 * to actually allow the user to pick the binary.
452 path = getenv("PATH");
456 FOREACH_WORD_SEPARATOR(w, l, path, ":", state) {
457 _cleanup_free_ char *p = NULL;
459 if (asprintf(&p, "%.*s/%s", (int) l, w, name) < 0)
462 if (access(p, X_OK) < 0)
466 *filename = path_kill_slashes(p);
477 bool paths_check_timestamp(const char* const* paths, usec_t *timestamp, bool update) {
478 bool changed = false;
479 const char* const* i;
486 STRV_FOREACH(i, paths) {
490 if (stat(*i, &stats) < 0)
493 u = timespec_load(&stats.st_mtim);
499 log_debug("timestamp of '%s' changed", *i);
501 /* update timestamp */
512 int fsck_exists(const char *fstype) {
515 checker = strappenda("fsck.", fstype);
516 return find_binary(checker, NULL);