[src/trunk]: src/usr.bin/xlint/lint1 lint: revert fix for endless loop in lex...

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

details:   https://anonhg.NetBSD.org/src/rev/ba1453bd06d5
branches:  trunk
changeset: 1021808:ba1453bd06d5
user:      rillig <rillig%NetBSD.org@localhost>
date:      Sat Jun 19 08:37:18 2021 +0000

description:
lint: revert fix for endless loop in lexer for string literals

String literals may contain null bytes, and these must be passed further
on.

This reintroduces the endless loop in the lexer, but that must be fixed
in another way that doesn't destroy the error handling.

diffstat:

 tests/usr.bin/xlint/lint1/lex_string.c   |  13 +++----------
 tests/usr.bin/xlint/lint1/lex_string.exp |  10 ++--------
 usr.bin/xlint/lint1/lex.c                |   6 +++---
 3 files changed, 8 insertions(+), 21 deletions(-)

diffs (71 lines):

diff -r c6f2e4c6bd6b -r ba1453bd06d5 tests/usr.bin/xlint/lint1/lex_string.c
--- a/tests/usr.bin/xlint/lint1/lex_string.c    Sat Jun 19 08:30:08 2021 +0000
+++ b/tests/usr.bin/xlint/lint1/lex_string.c    Sat Jun 19 08:37:18 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: lex_string.c,v 1.1 2021/06/19 08:30:08 rillig Exp $    */
+/*     $NetBSD: lex_string.c,v 1.2 2021/06/19 08:37:18 rillig Exp $    */
 # 3 "lex_string.c"
 
 /*
@@ -18,18 +18,11 @@
 
        sink("\0");
 
-       /* expect+5: unknown character \134 */
-       /* expect+4: syntax error '0' */
-       /* expect+3: unknown character \134 */
-       /* expect+2: unknown character \134 */
-       /* expect+1: unknown character \134 */
        sink("\0\0\0\0");
 
-       /* expect+1: unknown character \134 */
+       /* expect+1: no hex digits follow \x [74] */
        sink("\x");             /* unfinished */
 
-       /* expect+1: unknown character \134 */
+       /* expect+1: dubious escape \y [79] */
        sink("\y");             /* unknown escape sequence */
 }
-
-/* expect+1: cannot recover from previous errors */
diff -r c6f2e4c6bd6b -r ba1453bd06d5 tests/usr.bin/xlint/lint1/lex_string.exp
--- a/tests/usr.bin/xlint/lint1/lex_string.exp  Sat Jun 19 08:30:08 2021 +0000
+++ b/tests/usr.bin/xlint/lint1/lex_string.exp  Sat Jun 19 08:37:18 2021 +0000
@@ -1,8 +1,2 @@
-lex_string.c(26): error: unknown character \134 [250]
-lex_string.c(26): error: syntax error '0' [249]
-lex_string.c(26): error: unknown character \134 [250]
-lex_string.c(26): error: unknown character \134 [250]
-lex_string.c(26): error: unknown character \134 [250]
-lex_string.c(29): error: unknown character \134 [250]
-lex_string.c(32): error: unknown character \134 [250]
-lex_string.c(36): error: cannot recover from previous errors [224]
+lex_string.c(24): error: no hex digits follow \x [74]
+lex_string.c(27): warning: dubious escape \y [79]
diff -r c6f2e4c6bd6b -r ba1453bd06d5 usr.bin/xlint/lint1/lex.c
--- a/usr.bin/xlint/lint1/lex.c Sat Jun 19 08:30:08 2021 +0000
+++ b/usr.bin/xlint/lint1/lex.c Sat Jun 19 08:37:18 2021 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: lex.c,v 1.38 2021/06/18 20:29:00 rillig Exp $ */
+/* $NetBSD: lex.c,v 1.39 2021/06/19 08:37:18 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 1.38 2021/06/18 20:29:00 rillig Exp $");
+__RCSID("$NetBSD: lex.c,v 1.39 2021/06/19 08:37:18 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);