Merge pull request #23088 from yuwata/udev-event-blocker

udev: cleanups for event blocker

src/shared/udev-util.c

@@ -568,6 +568,19 @@ int udev_resolve_subsys_kernel(const char *string, char *result, size_t maxsize,
         return 0;
 }
 
+bool devpath_conflict(const char *a, const char *b) {
+        /* This returns true when two paths are equivalent, or one is a child of another. */
+
+        if (!a || !b)
+                return false;
+
+        for (; *a != '\0' && *b != '\0'; a++, b++)
+                if (*a != *b)
+                        return false;
+
+        return *a == '/' || *b == '/' || *a == *b;
+}
+
 int udev_queue_is_empty(void) {
         return access("/run/udev/queue", F_OK) < 0 ?
                 (errno == ENOENT ? true : -errno) : false;

src/shared/udev-util.h

@@ -50,6 +50,8 @@ size_t udev_replace_ifname(char *str);
 size_t udev_replace_chars(char *str, const char *allow);
 int udev_resolve_subsys_kernel(const char *string, char *result, size_t maxsize, bool read_value);
 
+bool devpath_conflict(const char *a, const char *b);
+
 int udev_queue_is_empty(void);
 int udev_queue_init(void);