From 47e5ae08a16d8d540ce8db74488530e976b78c33 Mon Sep 17 00:00:00 2001
From: Jilles Tjoelker <jilles@FreeBSD.org>
Date: Thu, 1 Oct 2009 21:40:08 +0000
Subject: [PATCH] sh: Disallow mismatched quotes in backticks (`...`).

Due to the amount of code removed by this, it seems that allowing unmatched
quotes was a deliberate imitation of System V sh and real ksh. Most other
shells do not allow unmatched quotes (e.g. bash, zsh, pdksh, NetBSD /bin/sh,
dash).

PR:		bin/137657
---
 bin/sh/parser.c                                   | 8 +-------
 tools/regression/bin/sh/errors/backquote-error2.0 | 7 +++++++
 2 files changed, 8 insertions(+), 7 deletions(-)
 create mode 100644 tools/regression/bin/sh/errors/backquote-error2.0

diff --git a/bin/sh/parser.c b/bin/sh/parser.c
index 54a80a715d06..9e861620e5f7 100644
--- a/bin/sh/parser.c
+++ b/bin/sh/parser.c
@@ -82,7 +82,6 @@ struct heredoc {
 
 
 STATIC struct heredoc *heredoclist;	/* list of here documents to read */
-STATIC int parsebackquote;	/* nonzero if we are inside backquotes */
 STATIC int doprompt;		/* if set, prompt the user */
 STATIC int needprompt;		/* true if interactive and at start of line */
 STATIC int lasttoken;		/* last token read */
@@ -1043,7 +1042,7 @@ readtoken1(int firstc, char const *syntax, char *eofmark, int striptabs)
 endword:
 	if (syntax == ARISYNTAX)
 		synerror("Missing '))'");
-	if (syntax != BASESYNTAX && ! parsebackquote && eofmark == NULL)
+	if (syntax != BASESYNTAX && eofmark == NULL)
 		synerror("Unterminated quoted string");
 	if (varnest != 0) {
 		startlinno = plinno;
@@ -1303,7 +1302,6 @@ parsesub: {
 
 parsebackq: {
 	struct nodelist **nlpp;
-	int savepbq;
 	union node *n;
 	char *volatile str;
 	struct jmploc jmploc;
@@ -1311,11 +1309,9 @@ parsebackq: {
 	int savelen;
 	int saveprompt;
 
-	savepbq = parsebackquote;
 	if (setjmp(jmploc.loc)) {
 		if (str)
 			ckfree(str);
-		parsebackquote = 0;
 		handler = savehandler;
 		longjmp(handler->loc, 1);
 	}
@@ -1397,7 +1393,6 @@ done:
 		nlpp = &(*nlpp)->next;
 	*nlpp = (struct nodelist *)stalloc(sizeof (struct nodelist));
 	(*nlpp)->next = NULL;
-	parsebackquote = oldstyle;
 
 	if (oldstyle) {
 		saveprompt = doprompt;
@@ -1433,7 +1428,6 @@ done:
 		str = NULL;
 		INTON;
 	}
-	parsebackquote = savepbq;
 	handler = savehandler;
 	if (arinest || dblquote)
 		USTPUTC(CTLBACKQ | CTLQUOTE, out);
diff --git a/tools/regression/bin/sh/errors/backquote-error2.0 b/tools/regression/bin/sh/errors/backquote-error2.0
new file mode 100644
index 000000000000..977c055a2af1
--- /dev/null
+++ b/tools/regression/bin/sh/errors/backquote-error2.0
@@ -0,0 +1,7 @@
+# $FreeBSD$
+
+sh -c 'echo `echo .BA"DCODE.`
+echo ".BAD"CODE.' 2>&1 | grep -q BADCODE && exit 1
+echo '`"`' | sh -n 2>/dev/null && exit 1
+echo '`'"'"'`' | sh -n 2>/dev/null && exit 1
+exit 0