xlowercase
xlowercase(user, user, sizeof(user));
xlowercase(domain, domain, sizeof(domain));
xlowercase(tag, tag, sizeof(tag));
xlowercase(buf, username, sizeof(buf));
xlowercase(maddr.user, xn->u.mailaddr.user,
xlowercase(node.u.user, xn->u.mailaddr.user,
xlowercase(key.data, key.data, strlen(key.data) + 1);
xlowercase(key.data, key.data, strlen(key.data) + 1);
xlowercase(buf, $2, sizeof(buf));
xlowercase(buf, $2, sizeof(buf));
void xlowercase(char *, const char *, size_t);