ash: let ignoreeof only affect interactive shells

Commit fb7d6c89 from Harald van Dijk's gwsh variant of ash
(https://github.com/hvdijk/gwsh):

    ignoreeof is documented as only having an effect for interactive shells,
    but is implemented as having mostly the same effect for interactive
    shells as for non-interactive shells. Change the implementation to match
    the documentation.

    Test case:

      $SHELL -o ignoreeof /dev/null

function                                             old     new   delta
cmdloop                                              359     361      +2
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/0 up/down: 2/0)                 Total: 2 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 4 insertions, 3 deletions

diff --git a/shell/ash.c b/shell/ash.c
index 5743b2377..b12b859d5 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -13508,12 +13508,13 @@ cmdloop(int top)
                         if (!top || numeof >= 50)
                                 break;
                         if (!stoppedjobs()) {
+                                if (!iflag)
+                                        break;
                                 if (!Iflag) {
-                                        if (iflag) {
-                                                newline_and_flush(stderr);
-                                        }
+                                        newline_and_flush(stderr);
                                         break;
                                 }
+                                /* "set -o ignoreeof" active, do not exit command loop on ^D */
                                 out2str("\nUse \"exit\" to leave shell.\n");
                         }
                         numeof++;