[src/trunk]: src/usr.bin/xlint/lint1 lint: fix hang on unfinished string lite...

[rillig <rillig%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/fd742a1b7f9a
branches:  trunk
changeset: 1021792:fd742a1b7f9a
user:      rillig <rillig%NetBSD.org@localhost>
date:      Fri Jun 18 20:29:00 2021 +0000

description:
lint: fix hang on unfinished string literal at end-of-file

The input file that triggered this bug was:

        a"b"c"d

Found using afl.

diffstat:

 usr.bin/xlint/lint1/lex.c |  6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

diffs (27 lines):

diff -r 974e83336894 -r fd742a1b7f9a usr.bin/xlint/lint1/lex.c
--- a/usr.bin/xlint/lint1/lex.c Fri Jun 18 13:57:52 2021 +0000
+++ b/usr.bin/xlint/lint1/lex.c Fri Jun 18 20:29:00 2021 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: lex.c,v 1.37 2021/06/15 20:46:45 rillig Exp $ */
+/* $NetBSD: lex.c,v 1.38 2021/06/18 20:29:00 rillig Exp $ */
 
 /*
  * Copyright (c) 1996 Christopher G. Demetriou.  All Rights Reserved.
@@ -38,7 +38,7 @@
 
 #include <sys/cdefs.h>
 #if defined(__RCSID) && !defined(lint)
-__RCSID("$NetBSD: lex.c,v 1.37 2021/06/15 20:46:45 rillig Exp $");
+__RCSID("$NetBSD: lex.c,v 1.38 2021/06/18 20:29:00 rillig Exp $");
 #endif
 
 #include <ctype.h>
@@ -1304,7 +1304,7 @@
        s = xmalloc(max = 64);
 
        len = 0;
-       while ((c = get_escaped_char('"')) >= 0) {
+       while ((c = get_escaped_char('"')) > 0) {
                /* +1 to reserve space for a trailing NUL character */
                if (len + 1 == max)
                        s = xrealloc(s, max *= 2);