bas.c: don't allow null bytes in variable name table, except at the end.

1 files changed, 3 insertions, 2 deletions

diff --git a/bas.c b/bas.c
index ab02b28..6be34f7 100644
--- a/bas.c
+++ b/bas.c
@@ -207,8 +207,9 @@ int vntable_ok(void) {
 	while(vp < vvstart) {
 		unsigned char c = program[vp];
 
-		/* treat a null byte as end-of-table, ignore any junk between it and VNTP. */
-		if(c == 0) break;
+		/* allow for (but don't require) dummy byte at VNTD. used to just
+		   quit when we hit 0, but 0 might be part of a scrambled table. */
+		if(c == 0 && vp == (vvstart - 1)) break;
 
 		vp++;