ash: eval: Check nflag in evaltree instead of cmdloop

Upstream commit:

    Date: Thu, 4 Jun 2020 21:53:55 +1000
    eval: Check nflag in evaltree instead of cmdloop

    This patch moves the nflag check from cmdloop into evaltree.  This
    is so that nflag will be in force even if we enter the shell via a
    path other than cmdloop, e.g., through sh -c.

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

3 files changed, 9 insertions, 1 deletions

diff --git a/shell/ash.c b/shell/ash.c
index cfe0433a8..2d2c09ba5 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -9299,6 +9299,9 @@ evaltree(union node *n, int flags)
 
         setstackmark(&smark);
 
+        if (nflag)
+                goto out;
+
         if (n == NULL) {
                 TRACE(("evaltree(NULL) called\n"));
                 goto out;
@@ -13557,7 +13560,7 @@ cmdloop(int top)
                                 out2str("\nUse \"exit\" to leave shell.\n");
                         }
                         numeof++;
-                } else if (nflag == 0) {
+                } else {
                         int i;
 
                         /* job_warning can only be 2,1,0. Here 2->1, 1/0->0 */
diff --git a/shell/ash_test/ash-misc/set-n1.right b/shell/ash_test/ash-misc/set-n1.right
new file mode 100644
index 000000000..ac01831a7
--- /dev/null
+++ b/shell/ash_test/ash-misc/set-n1.right
@@ -0,0 +1,3 @@
+set -n stops in -c?
+YES
+Ok:0
diff --git a/shell/ash_test/ash-misc/set-n1.tests b/shell/ash_test/ash-misc/set-n1.tests
new file mode 100755
index 000000000..90d0f9146
--- /dev/null
+++ b/shell/ash_test/ash-misc/set-n1.tests
@@ -0,0 +1,2 @@
+$THIS_SH -c "echo 'set -n stops in -c?'; set -n; echo NO" && echo YES
+echo Ok:$?