util: add chars_intersect() call

util.c

@@ -1193,6 +1193,17 @@ finish:
         return r;
 }
 
+bool chars_intersect(const char *a, const char *b) {
+        const char *p;
+
+        /* Returns true if any of the chars in a are in b. */
+        for (p = a; *p; p++)
+                if (strchr(b, *p))
+                        return true;
+
+        return false;
+}
+
 static const char *const ioprio_class_table[] = {
         [IOPRIO_CLASS_NONE] = "none",
         [IOPRIO_CLASS_RT] = "realtime",

util.h

@@ -157,6 +157,8 @@ char *bus_path_unescape(const char *s);
 
 bool ignore_file(const char *filename);
 
+bool chars_intersect(const char *a, const char *b);
+
 #define DEFINE_STRING_TABLE_LOOKUP(name,type)                           \
         const char *name##_to_string(type i) {                          \
                 if (i < 0 || i >= (type) ELEMENTSOF(name##_table))      \