From 7ae1cc16b4ecec930cd776f9ed688b6d4d53a166 Mon Sep 17 00:00:00 2001
From: Denis Vlasenko <vda.linux@googlemail.com>
Date: Sun, 20 Jul 2008 23:03:23 +0000
Subject: [PATCH] msh: fix "while...continue" bug 3884.

---
 shell/msh.c                                       |  8 ++++++++
 shell/msh_test/msh-execution/many_continues.right |  1 +
 shell/msh_test/msh-execution/many_continues.tests | 15 +++++++++++++++
 3 files changed, 24 insertions(+)
 create mode 100644 shell/msh_test/msh-execution/many_continues.right
 create mode 100755 shell/msh_test/msh-execution/many_continues.tests

diff --git a/shell/msh.c b/shell/msh.c
index 44213c657..eb17eb668 100644
--- a/shell/msh.c
+++ b/shell/msh.c
@@ -2573,6 +2573,10 @@ static int execute(struct op *t, int *pin, int *pout, int no_fork)
 		while (setjmp(bc.brkpt))
 			if (isbreak)
 				goto broken;
+		/* Restore areanum value. It may be incremented by execute()
+		 * below, and then "continue" may jump back to setjmp above */
+		areanum = a + 1;
+		freearea(areanum + 1);
 		brkset(&bc);
 		for (t1 = t->left; i-- && *wp != NULL;) {
 			setval(vp, *wp++);
@@ -2586,6 +2590,10 @@ static int execute(struct op *t, int *pin, int *pout, int no_fork)
 		while (setjmp(bc.brkpt))
 			if (isbreak)
 				goto broken;
+		/* Restore areanum value. It may be incremented by execute()
+		 * below, and then "continue" may jump back to setjmp above */
+		areanum = a + 1;
+		freearea(areanum + 1);
 		brkset(&bc);
 		t1 = t->left;
 		while ((execute(t1, pin, pout, /* no_fork: */ 0) == 0) == (t->op_type == TWHILE))
diff --git a/shell/msh_test/msh-execution/many_continues.right b/shell/msh_test/msh-execution/many_continues.right
new file mode 100644
index 000000000..d86bac9de
--- /dev/null
+++ b/shell/msh_test/msh-execution/many_continues.right
@@ -0,0 +1 @@
+OK
diff --git a/shell/msh_test/msh-execution/many_continues.tests b/shell/msh_test/msh-execution/many_continues.tests
new file mode 100755
index 000000000..86c729abc
--- /dev/null
+++ b/shell/msh_test/msh-execution/many_continues.tests
@@ -0,0 +1,15 @@
+if test $# = 0; then
+    # Child will kill us in 1 second
+    "$THIS_SH" "$0" $$ &
+
+    # Loop many, many times
+    trap 'echo OK; exit 0' 15
+    while true; do
+	continue
+    done
+    echo BAD
+    exit 1
+fi
+
+sleep 1
+kill $1