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-rw-r--r--src/basic/path-util.c1150
1 files changed, 1150 insertions, 0 deletions
diff --git a/src/basic/path-util.c b/src/basic/path-util.c
new file mode 100644
index 0000000..2215173
--- /dev/null
+++ b/src/basic/path-util.c
@@ -0,0 +1,1150 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+
+#include <errno.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+/* When we include libgen.h because we need dirname() we immediately
+ * undefine basename() since libgen.h defines it as a macro to the
+ * POSIX version which is really broken. We prefer GNU basename(). */
+#include <libgen.h>
+#undef basename
+
+#include "alloc-util.h"
+#include "extract-word.h"
+#include "fs-util.h"
+#include "glob-util.h"
+#include "log.h"
+#include "macro.h"
+#include "missing.h"
+#include "parse-util.h"
+#include "path-util.h"
+#include "stat-util.h"
+#include "string-util.h"
+#include "strv.h"
+#include "time-util.h"
+#include "utf8.h"
+
+bool path_is_absolute(const char *p) {
+ return p[0] == '/';
+}
+
+bool is_path(const char *p) {
+ return !!strchr(p, '/');
+}
+
+int path_split_and_make_absolute(const char *p, char ***ret) {
+ char **l;
+ int r;
+
+ assert(p);
+ assert(ret);
+
+ l = strv_split(p, ":");
+ if (!l)
+ return -ENOMEM;
+
+ r = path_strv_make_absolute_cwd(l);
+ if (r < 0) {
+ strv_free(l);
+ return r;
+ }
+
+ *ret = l;
+ return r;
+}
+
+char *path_make_absolute(const char *p, const char *prefix) {
+ assert(p);
+
+ /* Makes every item in the list an absolute path by prepending
+ * the prefix, if specified and necessary */
+
+ if (path_is_absolute(p) || isempty(prefix))
+ return strdup(p);
+
+ if (endswith(prefix, "/"))
+ return strjoin(prefix, p);
+ else
+ return strjoin(prefix, "/", p);
+}
+
+int safe_getcwd(char **ret) {
+ char *cwd;
+
+ cwd = get_current_dir_name();
+ if (!cwd)
+ return negative_errno();
+
+ /* Let's make sure the directory is really absolute, to protect us from the logic behind
+ * CVE-2018-1000001 */
+ if (cwd[0] != '/') {
+ free(cwd);
+ return -ENOMEDIUM;
+ }
+
+ *ret = cwd;
+ return 0;
+}
+
+int path_make_absolute_cwd(const char *p, char **ret) {
+ char *c;
+ int r;
+
+ assert(p);
+ assert(ret);
+
+ /* Similar to path_make_absolute(), but prefixes with the
+ * current working directory. */
+
+ if (path_is_absolute(p))
+ c = strdup(p);
+ else {
+ _cleanup_free_ char *cwd = NULL;
+
+ r = safe_getcwd(&cwd);
+ if (r < 0)
+ return r;
+
+ c = path_join(cwd, p);
+ }
+ if (!c)
+ return -ENOMEM;
+
+ *ret = c;
+ return 0;
+}
+
+int path_make_relative(const char *from_dir, const char *to_path, char **_r) {
+ char *f, *t, *r, *p;
+ unsigned n_parents = 0;
+
+ assert(from_dir);
+ assert(to_path);
+ assert(_r);
+
+ /* Strips the common part, and adds ".." elements as necessary. */
+
+ if (!path_is_absolute(from_dir) || !path_is_absolute(to_path))
+ return -EINVAL;
+
+ f = strdupa(from_dir);
+ t = strdupa(to_path);
+
+ path_simplify(f, true);
+ path_simplify(t, true);
+
+ /* Skip the common part. */
+ for (;;) {
+ size_t a, b;
+
+ f += *f == '/';
+ t += *t == '/';
+
+ if (!*f) {
+ if (!*t)
+ /* from_dir equals to_path. */
+ r = strdup(".");
+ else
+ /* from_dir is a parent directory of to_path. */
+ r = strdup(t);
+ if (!r)
+ return -ENOMEM;
+
+ *_r = r;
+ return 0;
+ }
+
+ if (!*t)
+ break;
+
+ a = strcspn(f, "/");
+ b = strcspn(t, "/");
+
+ if (a != b || memcmp(f, t, a) != 0)
+ break;
+
+ f += a;
+ t += b;
+ }
+
+ /* If we're here, then "from_dir" has one or more elements that need to
+ * be replaced with "..". */
+
+ /* Count the number of necessary ".." elements. */
+ for (; *f;) {
+ size_t w;
+
+ w = strcspn(f, "/");
+
+ /* If this includes ".." we can't do a simple series of "..", refuse */
+ if (w == 2 && f[0] == '.' && f[1] == '.')
+ return -EINVAL;
+
+ /* Count number of elements */
+ n_parents++;
+
+ f += w;
+ f += *f == '/';
+ }
+
+ r = new(char, n_parents * 3 + strlen(t) + 1);
+ if (!r)
+ return -ENOMEM;
+
+ for (p = r; n_parents > 0; n_parents--)
+ p = mempcpy(p, "../", 3);
+
+ if (*t)
+ strcpy(p, t);
+ else
+ /* Remove trailing slash */
+ *(--p) = 0;
+
+ *_r = r;
+ return 0;
+}
+
+int path_strv_make_absolute_cwd(char **l) {
+ char **s;
+ int r;
+
+ /* Goes through every item in the string list and makes it
+ * absolute. This works in place and won't rollback any
+ * changes on failure. */
+
+ STRV_FOREACH(s, l) {
+ char *t;
+
+ r = path_make_absolute_cwd(*s, &t);
+ if (r < 0)
+ return r;
+
+ path_simplify(t, false);
+ free_and_replace(*s, t);
+ }
+
+ return 0;
+}
+
+char **path_strv_resolve(char **l, const char *root) {
+ char **s;
+ unsigned k = 0;
+ bool enomem = false;
+ int r;
+
+ if (strv_isempty(l))
+ return l;
+
+ /* Goes through every item in the string list and canonicalize
+ * the path. This works in place and won't rollback any
+ * changes on failure. */
+
+ STRV_FOREACH(s, l) {
+ _cleanup_free_ char *orig = NULL;
+ char *t, *u;
+
+ if (!path_is_absolute(*s)) {
+ free(*s);
+ continue;
+ }
+
+ if (root) {
+ orig = *s;
+ t = prefix_root(root, orig);
+ if (!t) {
+ enomem = true;
+ continue;
+ }
+ } else
+ t = *s;
+
+ r = chase_symlinks(t, root, 0, &u);
+ if (r == -ENOENT) {
+ if (root) {
+ u = TAKE_PTR(orig);
+ free(t);
+ } else
+ u = t;
+ } else if (r < 0) {
+ free(t);
+
+ if (r == -ENOMEM)
+ enomem = true;
+
+ continue;
+ } else if (root) {
+ char *x;
+
+ free(t);
+ x = path_startswith(u, root);
+ if (x) {
+ /* restore the slash if it was lost */
+ if (!startswith(x, "/"))
+ *(--x) = '/';
+
+ t = strdup(x);
+ free(u);
+ if (!t) {
+ enomem = true;
+ continue;
+ }
+ u = t;
+ } else {
+ /* canonicalized path goes outside of
+ * prefix, keep the original path instead */
+ free_and_replace(u, orig);
+ }
+ } else
+ free(t);
+
+ l[k++] = u;
+ }
+
+ l[k] = NULL;
+
+ if (enomem)
+ return NULL;
+
+ return l;
+}
+
+char **path_strv_resolve_uniq(char **l, const char *root) {
+
+ if (strv_isempty(l))
+ return l;
+
+ if (!path_strv_resolve(l, root))
+ return NULL;
+
+ return strv_uniq(l);
+}
+
+char *path_simplify(char *path, bool kill_dots) {
+ char *f, *t;
+ bool slash = false, ignore_slash = false, absolute;
+
+ assert(path);
+
+ /* Removes redundant inner and trailing slashes. Also removes unnecessary dots
+ * if kill_dots is true. Modifies the passed string in-place.
+ *
+ * ///foo//./bar/. becomes /foo/./bar/. (if kill_dots is false)
+ * ///foo//./bar/. becomes /foo/bar (if kill_dots is true)
+ * .//./foo//./bar/. becomes ././foo/./bar/. (if kill_dots is false)
+ * .//./foo//./bar/. becomes foo/bar (if kill_dots is true)
+ */
+
+ if (isempty(path))
+ return path;
+
+ absolute = path_is_absolute(path);
+
+ f = path;
+ if (kill_dots && *f == '.' && IN_SET(f[1], 0, '/')) {
+ ignore_slash = true;
+ f++;
+ }
+
+ for (t = path; *f; f++) {
+
+ if (*f == '/') {
+ slash = true;
+ continue;
+ }
+
+ if (slash) {
+ if (kill_dots && *f == '.' && IN_SET(f[1], 0, '/'))
+ continue;
+
+ slash = false;
+ if (ignore_slash)
+ ignore_slash = false;
+ else
+ *(t++) = '/';
+ }
+
+ *(t++) = *f;
+ }
+
+ /* Special rule, if we stripped everything, we either need a "/" (for the root directory)
+ * or "." for the current directory */
+ if (t == path) {
+ if (absolute)
+ *(t++) = '/';
+ else
+ *(t++) = '.';
+ }
+
+ *t = 0;
+ return path;
+}
+
+char* path_startswith(const char *path, const char *prefix) {
+ assert(path);
+ assert(prefix);
+
+ /* Returns a pointer to the start of the first component after the parts matched by
+ * the prefix, iff
+ * - both paths are absolute or both paths are relative,
+ * and
+ * - each component in prefix in turn matches a component in path at the same position.
+ * An empty string will be returned when the prefix and path are equivalent.
+ *
+ * Returns NULL otherwise.
+ */
+
+ if ((path[0] == '/') != (prefix[0] == '/'))
+ return NULL;
+
+ for (;;) {
+ size_t a, b;
+
+ path += strspn(path, "/");
+ prefix += strspn(prefix, "/");
+
+ if (*prefix == 0)
+ return (char*) path;
+
+ if (*path == 0)
+ return NULL;
+
+ a = strcspn(path, "/");
+ b = strcspn(prefix, "/");
+
+ if (a != b)
+ return NULL;
+
+ if (memcmp(path, prefix, a) != 0)
+ return NULL;
+
+ path += a;
+ prefix += b;
+ }
+}
+
+int path_compare(const char *a, const char *b) {
+ int d;
+
+ assert(a);
+ assert(b);
+
+ /* A relative path and an absolute path must not compare as equal.
+ * Which one is sorted before the other does not really matter.
+ * Here a relative path is ordered before an absolute path. */
+ d = (a[0] == '/') - (b[0] == '/');
+ if (d != 0)
+ return d;
+
+ for (;;) {
+ size_t j, k;
+
+ a += strspn(a, "/");
+ b += strspn(b, "/");
+
+ if (*a == 0 && *b == 0)
+ return 0;
+
+ /* Order prefixes first: "/foo" before "/foo/bar" */
+ if (*a == 0)
+ return -1;
+ if (*b == 0)
+ return 1;
+
+ j = strcspn(a, "/");
+ k = strcspn(b, "/");
+
+ /* Alphabetical sort: "/foo/aaa" before "/foo/b" */
+ d = memcmp(a, b, MIN(j, k));
+ if (d != 0)
+ return (d > 0) - (d < 0); /* sign of d */
+
+ /* Sort "/foo/a" before "/foo/aaa" */
+ d = (j > k) - (j < k); /* sign of (j - k) */
+ if (d != 0)
+ return d;
+
+ a += j;
+ b += k;
+ }
+}
+
+bool path_equal(const char *a, const char *b) {
+ return path_compare(a, b) == 0;
+}
+
+bool path_equal_or_files_same(const char *a, const char *b, int flags) {
+ return path_equal(a, b) || files_same(a, b, flags) > 0;
+}
+
+char* path_join_internal(const char *first, ...) {
+ char *joined, *q;
+ const char *p;
+ va_list ap;
+ bool slash;
+ size_t sz;
+
+ /* Joins all listed strings until the sentinel and places a "/" between them unless the strings end/begin
+ * already with one so that it is unnecessary. Note that slashes which are already duplicate won't be
+ * removed. The string returned is hence always equal to or longer than the sum of the lengths of each
+ * individual string.
+ *
+ * Note: any listed empty string is simply skipped. This can be useful for concatenating strings of which some
+ * are optional.
+ *
+ * Examples:
+ *
+ * path_join("foo", "bar") → "foo/bar"
+ * path_join("foo/", "bar") → "foo/bar"
+ * path_join("", "foo", "", "bar", "") → "foo/bar" */
+
+ sz = strlen_ptr(first);
+ va_start(ap, first);
+ while ((p = va_arg(ap, char*)) != (const char*) -1)
+ if (!isempty(p))
+ sz += 1 + strlen(p);
+ va_end(ap);
+
+ joined = new(char, sz + 1);
+ if (!joined)
+ return NULL;
+
+ if (!isempty(first)) {
+ q = stpcpy(joined, first);
+ slash = endswith(first, "/");
+ } else {
+ /* Skip empty items */
+ joined[0] = 0;
+ q = joined;
+ slash = true; /* no need to generate a slash anymore */
+ }
+
+ va_start(ap, first);
+ while ((p = va_arg(ap, char*)) != (const char*) -1) {
+ if (isempty(p))
+ continue;
+
+ if (!slash && p[0] != '/')
+ *(q++) = '/';
+
+ q = stpcpy(q, p);
+ slash = endswith(p, "/");
+ }
+ va_end(ap);
+
+ return joined;
+}
+
+int find_binary(const char *name, char **ret) {
+ int last_error, r;
+ const char *p;
+
+ assert(name);
+
+ if (is_path(name)) {
+ if (access(name, X_OK) < 0)
+ return -errno;
+
+ if (ret) {
+ r = path_make_absolute_cwd(name, ret);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+ }
+
+ /**
+ * Plain getenv, not secure_getenv, because we want
+ * to actually allow the user to pick the binary.
+ */
+ p = getenv("PATH");
+ if (!p)
+ p = DEFAULT_PATH;
+
+ last_error = -ENOENT;
+
+ for (;;) {
+ _cleanup_free_ char *j = NULL, *element = NULL;
+
+ r = extract_first_word(&p, &element, ":", EXTRACT_RELAX|EXTRACT_DONT_COALESCE_SEPARATORS);
+ if (r < 0)
+ return r;
+ if (r == 0)
+ break;
+
+ if (!path_is_absolute(element))
+ continue;
+
+ j = strjoin(element, "/", name);
+ if (!j)
+ return -ENOMEM;
+
+ if (access(j, X_OK) >= 0) {
+ /* Found it! */
+
+ if (ret) {
+ *ret = path_simplify(j, false);
+ j = NULL;
+ }
+
+ return 0;
+ }
+
+ last_error = -errno;
+ }
+
+ return last_error;
+}
+
+bool paths_check_timestamp(const char* const* paths, usec_t *timestamp, bool update) {
+ bool changed = false;
+ const char* const* i;
+
+ assert(timestamp);
+
+ if (!paths)
+ return false;
+
+ STRV_FOREACH(i, paths) {
+ struct stat stats;
+ usec_t u;
+
+ if (stat(*i, &stats) < 0)
+ continue;
+
+ u = timespec_load(&stats.st_mtim);
+
+ /* first check */
+ if (*timestamp >= u)
+ continue;
+
+ log_debug("timestamp of '%s' changed", *i);
+
+ /* update timestamp */
+ if (update) {
+ *timestamp = u;
+ changed = true;
+ } else
+ return true;
+ }
+
+ return changed;
+}
+
+static int binary_is_good(const char *binary) {
+ _cleanup_free_ char *p = NULL, *d = NULL;
+ int r;
+
+ r = find_binary(binary, &p);
+ if (r == -ENOENT)
+ return 0;
+ if (r < 0)
+ return r;
+
+ /* An fsck that is linked to /bin/true is a non-existent
+ * fsck */
+
+ r = readlink_malloc(p, &d);
+ if (r == -EINVAL) /* not a symlink */
+ return 1;
+ if (r < 0)
+ return r;
+
+ return !PATH_IN_SET(d, "true"
+ "/bin/true",
+ "/usr/bin/true",
+ "/dev/null");
+}
+
+int fsck_exists(const char *fstype) {
+ const char *checker;
+
+ assert(fstype);
+
+ if (streq(fstype, "auto"))
+ return -EINVAL;
+
+ checker = strjoina("fsck.", fstype);
+ return binary_is_good(checker);
+}
+
+int mkfs_exists(const char *fstype) {
+ const char *mkfs;
+
+ assert(fstype);
+
+ if (streq(fstype, "auto"))
+ return -EINVAL;
+
+ mkfs = strjoina("mkfs.", fstype);
+ return binary_is_good(mkfs);
+}
+
+char *prefix_root(const char *root, const char *path) {
+ char *n, *p;
+ size_t l;
+
+ /* If root is passed, prefixes path with it. Otherwise returns
+ * it as is. */
+
+ assert(path);
+
+ /* First, drop duplicate prefixing slashes from the path */
+ while (path[0] == '/' && path[1] == '/')
+ path++;
+
+ if (empty_or_root(root))
+ return strdup(path);
+
+ l = strlen(root) + 1 + strlen(path) + 1;
+
+ n = new(char, l);
+ if (!n)
+ return NULL;
+
+ p = stpcpy(n, root);
+
+ while (p > n && p[-1] == '/')
+ p--;
+
+ if (path[0] != '/')
+ *(p++) = '/';
+
+ strcpy(p, path);
+ return n;
+}
+
+int parse_path_argument_and_warn(const char *path, bool suppress_root, char **arg) {
+ char *p;
+ int r;
+
+ /*
+ * This function is intended to be used in command line
+ * parsers, to handle paths that are passed in. It makes the
+ * path absolute, and reduces it to NULL if omitted or
+ * root (the latter optionally).
+ *
+ * NOTE THAT THIS WILL FREE THE PREVIOUS ARGUMENT POINTER ON
+ * SUCCESS! Hence, do not pass in uninitialized pointers.
+ */
+
+ if (isempty(path)) {
+ *arg = mfree(*arg);
+ return 0;
+ }
+
+ r = path_make_absolute_cwd(path, &p);
+ if (r < 0)
+ return log_error_errno(r, "Failed to parse path \"%s\" and make it absolute: %m", path);
+
+ path_simplify(p, false);
+ if (suppress_root && empty_or_root(p))
+ p = mfree(p);
+
+ free_and_replace(*arg, p);
+
+ return 0;
+}
+
+char* dirname_malloc(const char *path) {
+ char *d, *dir, *dir2;
+
+ assert(path);
+
+ d = strdup(path);
+ if (!d)
+ return NULL;
+
+ dir = dirname(d);
+ assert(dir);
+
+ if (dir == d)
+ return d;
+
+ dir2 = strdup(dir);
+ free(d);
+
+ return dir2;
+}
+
+const char *last_path_component(const char *path) {
+
+ /* Finds the last component of the path, preserving the optional trailing slash that signifies a directory.
+ *
+ * a/b/c → c
+ * a/b/c/ → c/
+ * x → x
+ * x/ → x/
+ * /y → y
+ * /y/ → y/
+ * / → /
+ * // → /
+ * /foo/a → a
+ * /foo/a/ → a/
+ *
+ * Also, the empty string is mapped to itself.
+ *
+ * This is different than basename(), which returns "" when a trailing slash is present.
+ */
+
+ unsigned l, k;
+
+ if (!path)
+ return NULL;
+
+ l = k = strlen(path);
+ if (l == 0) /* special case — an empty string */
+ return path;
+
+ while (k > 0 && path[k-1] == '/')
+ k--;
+
+ if (k == 0) /* the root directory */
+ return path + l - 1;
+
+ while (k > 0 && path[k-1] != '/')
+ k--;
+
+ return path + k;
+}
+
+int path_extract_filename(const char *p, char **ret) {
+ _cleanup_free_ char *a = NULL;
+ const char *c, *e = NULL, *q;
+
+ /* Extracts the filename part (i.e. right-most component) from a path, i.e. string that passes
+ * filename_is_valid(). A wrapper around last_path_component(), but eats up trailing slashes. */
+
+ if (!p)
+ return -EINVAL;
+
+ c = last_path_component(p);
+
+ for (q = c; *q != 0; q++)
+ if (*q != '/')
+ e = q + 1;
+
+ if (!e) /* no valid character? */
+ return -EINVAL;
+
+ a = strndup(c, e - c);
+ if (!a)
+ return -ENOMEM;
+
+ if (!filename_is_valid(a))
+ return -EINVAL;
+
+ *ret = TAKE_PTR(a);
+
+ return 0;
+}
+
+bool filename_is_valid(const char *p) {
+ const char *e;
+
+ if (isempty(p))
+ return false;
+
+ if (dot_or_dot_dot(p))
+ return false;
+
+ e = strchrnul(p, '/');
+ if (*e != 0)
+ return false;
+
+ if (e - p > FILENAME_MAX) /* FILENAME_MAX is counted *without* the trailing NUL byte */
+ return false;
+
+ return true;
+}
+
+bool path_is_valid(const char *p) {
+
+ if (isempty(p))
+ return false;
+
+ if (strlen(p) >= PATH_MAX) /* PATH_MAX is counted *with* the trailing NUL byte */
+ return false;
+
+ return true;
+}
+
+bool path_is_normalized(const char *p) {
+
+ if (!path_is_valid(p))
+ return false;
+
+ if (dot_or_dot_dot(p))
+ return false;
+
+ if (startswith(p, "../") || endswith(p, "/..") || strstr(p, "/../"))
+ return false;
+
+ if (startswith(p, "./") || endswith(p, "/.") || strstr(p, "/./"))
+ return false;
+
+ if (strstr(p, "//"))
+ return false;
+
+ return true;
+}
+
+char *file_in_same_dir(const char *path, const char *filename) {
+ char *e, *ret;
+ size_t k;
+
+ assert(path);
+ assert(filename);
+
+ /* This removes the last component of path and appends
+ * filename, unless the latter is absolute anyway or the
+ * former isn't */
+
+ if (path_is_absolute(filename))
+ return strdup(filename);
+
+ e = strrchr(path, '/');
+ if (!e)
+ return strdup(filename);
+
+ k = strlen(filename);
+ ret = new(char, (e + 1 - path) + k + 1);
+ if (!ret)
+ return NULL;
+
+ memcpy(mempcpy(ret, path, e + 1 - path), filename, k + 1);
+ return ret;
+}
+
+bool hidden_or_backup_file(const char *filename) {
+ const char *p;
+
+ assert(filename);
+
+ if (filename[0] == '.' ||
+ streq(filename, "lost+found") ||
+ streq(filename, "aquota.user") ||
+ streq(filename, "aquota.group") ||
+ endswith(filename, "~"))
+ return true;
+
+ p = strrchr(filename, '.');
+ if (!p)
+ return false;
+
+ /* Please, let's not add more entries to the list below. If external projects think it's a good idea to come up
+ * with always new suffixes and that everybody else should just adjust to that, then it really should be on
+ * them. Hence, in future, let's not add any more entries. Instead, let's ask those packages to instead adopt
+ * one of the generic suffixes/prefixes for hidden files or backups, possibly augmented with an additional
+ * string. Specifically: there's now:
+ *
+ * The generic suffixes "~" and ".bak" for backup files
+ * The generic prefix "." for hidden files
+ *
+ * Thus, if a new package manager "foopkg" wants its own set of ".foopkg-new", ".foopkg-old", ".foopkg-dist"
+ * or so registered, let's refuse that and ask them to use ".foopkg.new", ".foopkg.old" or ".foopkg~" instead.
+ */
+
+ return STR_IN_SET(p + 1,
+ "rpmnew",
+ "rpmsave",
+ "rpmorig",
+ "dpkg-old",
+ "dpkg-new",
+ "dpkg-tmp",
+ "dpkg-dist",
+ "dpkg-bak",
+ "dpkg-backup",
+ "dpkg-remove",
+ "ucf-new",
+ "ucf-old",
+ "ucf-dist",
+ "swp",
+ "bak",
+ "old",
+ "new");
+}
+
+bool is_device_path(const char *path) {
+
+ /* Returns true on paths that likely refer to a device, either by path in sysfs or to something in /dev */
+
+ return PATH_STARTSWITH_SET(path, "/dev/", "/sys/");
+}
+
+bool valid_device_node_path(const char *path) {
+
+ /* Some superficial checks whether the specified path is a valid device node path, all without looking at the
+ * actual device node. */
+
+ if (!PATH_STARTSWITH_SET(path, "/dev/", "/run/systemd/inaccessible/"))
+ return false;
+
+ if (endswith(path, "/")) /* can't be a device node if it ends in a slash */
+ return false;
+
+ return path_is_normalized(path);
+}
+
+bool valid_device_allow_pattern(const char *path) {
+ assert(path);
+
+ /* Like valid_device_node_path(), but also allows full-subsystem expressions, like DeviceAllow= and DeviceDeny=
+ * accept it */
+
+ if (STARTSWITH_SET(path, "block-", "char-"))
+ return true;
+
+ return valid_device_node_path(path);
+}
+
+int systemd_installation_has_version(const char *root, unsigned minimal_version) {
+ const char *pattern;
+ int r;
+
+ /* Try to guess if systemd installation is later than the specified version. This
+ * is hacky and likely to yield false negatives, particularly if the installation
+ * is non-standard. False positives should be relatively rare.
+ */
+
+ NULSTR_FOREACH(pattern,
+ /* /lib works for systems without usr-merge, and for systems with a sane
+ * usr-merge, where /lib is a symlink to /usr/lib. /usr/lib is necessary
+ * for Gentoo which does a merge without making /lib a symlink.
+ */
+ "lib/systemd/libsystemd-shared-*.so\0"
+ "lib64/systemd/libsystemd-shared-*.so\0"
+ "usr/lib/systemd/libsystemd-shared-*.so\0"
+ "usr/lib64/systemd/libsystemd-shared-*.so\0") {
+
+ _cleanup_strv_free_ char **names = NULL;
+ _cleanup_free_ char *path = NULL;
+ char *c, **name;
+
+ path = prefix_root(root, pattern);
+ if (!path)
+ return -ENOMEM;
+
+ r = glob_extend(&names, path);
+ if (r == -ENOENT)
+ continue;
+ if (r < 0)
+ return r;
+
+ assert_se(c = endswith(path, "*.so"));
+ *c = '\0'; /* truncate the glob part */
+
+ STRV_FOREACH(name, names) {
+ /* This is most likely to run only once, hence let's not optimize anything. */
+ char *t, *t2;
+ unsigned version;
+
+ t = startswith(*name, path);
+ if (!t)
+ continue;
+
+ t2 = endswith(t, ".so");
+ if (!t2)
+ continue;
+
+ t2[0] = '\0'; /* truncate the suffix */
+
+ r = safe_atou(t, &version);
+ if (r < 0) {
+ log_debug_errno(r, "Found libsystemd shared at \"%s.so\", but failed to parse version: %m", *name);
+ continue;
+ }
+
+ log_debug("Found libsystemd shared at \"%s.so\", version %u (%s).",
+ *name, version,
+ version >= minimal_version ? "OK" : "too old");
+ if (version >= minimal_version)
+ return true;
+ }
+ }
+
+ return false;
+}
+
+bool dot_or_dot_dot(const char *path) {
+ if (!path)
+ return false;
+ if (path[0] != '.')
+ return false;
+ if (path[1] == 0)
+ return true;
+ if (path[1] != '.')
+ return false;
+
+ return path[2] == 0;
+}
+
+bool empty_or_root(const char *root) {
+
+ /* For operations relative to some root directory, returns true if the specified root directory is redundant,
+ * i.e. either / or NULL or the empty string or any equivalent. */
+
+ if (!root)
+ return true;
+
+ return root[strspn(root, "/")] == 0;
+}
+
+int path_simplify_and_warn(
+ char *path,
+ unsigned flag,
+ const char *unit,
+ const char *filename,
+ unsigned line,
+ const char *lvalue) {
+
+ bool absolute, fatal = flag & PATH_CHECK_FATAL;
+
+ assert(!FLAGS_SET(flag, PATH_CHECK_ABSOLUTE | PATH_CHECK_RELATIVE));
+
+ if (!utf8_is_valid(path)) {
+ log_syntax_invalid_utf8(unit, LOG_ERR, filename, line, path);
+ return -EINVAL;
+ }
+
+ if (flag & (PATH_CHECK_ABSOLUTE | PATH_CHECK_RELATIVE)) {
+ absolute = path_is_absolute(path);
+
+ if (!absolute && (flag & PATH_CHECK_ABSOLUTE)) {
+ log_syntax(unit, LOG_ERR, filename, line, 0,
+ "%s= path is not absolute%s: %s",
+ lvalue, fatal ? "" : ", ignoring", path);
+ return -EINVAL;
+ }
+
+ if (absolute && (flag & PATH_CHECK_RELATIVE)) {
+ log_syntax(unit, LOG_ERR, filename, line, 0,
+ "%s= path is absolute%s: %s",
+ lvalue, fatal ? "" : ", ignoring", path);
+ return -EINVAL;
+ }
+ }
+
+ path_simplify(path, true);
+
+ if (!path_is_normalized(path)) {
+ log_syntax(unit, LOG_ERR, filename, line, 0,
+ "%s= path is not normalized%s: %s",
+ lvalue, fatal ? "" : ", ignoring", path);
+ return -EINVAL;
+ }
+
+ if (!path_is_valid(path)) {
+ log_syntax(unit, LOG_ERR, filename, line, 0,
+ "%s= path has invalid length (%zu bytes)%s.",
+ lvalue, strlen(path), fatal ? "" : ", ignoring");
+ return -EINVAL;
+ }
+
+ return 0;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-23 02:28:29 +0000