for(i = 0; i < LENGTH(rules); i++) {
r = &rules[i];
if((!r->title || strstr(c->name, r->title))
- && (!ch.res_class || !r->class || strstr(ch.res_class, r->class))
- && (!ch.res_name || !r->instance || strstr(ch.res_name, r->instance)))
+ && (!r->class || (ch.res_class && strstr(ch.res_class, r->class)))
+ && (!r->instance || (ch.res_name && strstr(ch.res_name, r->instance)))) {
{
c->isfloating = r->isfloating;
if(r->tag) {