commit 1d9a178e6081328b51cc98a09db94b310f12b811
from: Omar Polo <op@omarpolo.com>
date: Tue Jul 05 16:38:18 2022 UTC

cast argument to is*()

otherwise there can be issues on arches with signed chars (as amd64)

commit - c5cb3a171413cbc4a5fda4286551ce51b7dc658c
commit + 1d9a178e6081328b51cc98a09db94b310f12b811
blob - ab2bdd312118391b33b3e690d66fe21c7b798c28
blob + 776309b48bd61a27a68a2d8d90e7c45a0da6c5ac
--- lstun.c
+++ lstun.c
@@ -384,7 +384,7 @@ parse_tflag(void)
 {
 	const char *c;
 
-	if (isdigit(*ssh_tflag)) {
+	if (isdigit((unsigned char)*ssh_tflag)) {
 		strlcpy(ssh_host, "localhost", sizeof(ssh_host));
 		if (copysec(ssh_tflag, ssh_port, sizeof(ssh_port)) == NULL)
 			goto err;