[newlib-cygwin] Cygwin: pty: Add FreeConsole to destructor of pty slave.

[Corinna Vinschen <corinna@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=071b8e0cbd4be33449c12bb0d58f514ed8ef893c

commit 071b8e0cbd4be33449c12bb0d58f514ed8ef893c
Author: Takashi Yano via Cygwin-patches <cygwin-patches@cygwin.com>
Date:   Fri Mar 13 12:06:49 2020 +0900

    Cygwin: pty: Add FreeConsole to destructor of pty slave.
    
    - When pseudo console is closed, all the processes attched to the
      pseudo console are terminated. This causes the problem reported
      in https://sourceware.org/pipermail/cygwin/2020-March/244046.html.
      This patch fixes the issue.

Diff:
---
 winsup/cygwin/fhandler_tty.cc | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/winsup/cygwin/fhandler_tty.cc b/winsup/cygwin/fhandler_tty.cc
index b42e0aeb6..b2e725d5d 100644
--- a/winsup/cygwin/fhandler_tty.cc
+++ b/winsup/cygwin/fhandler_tty.cc
@@ -706,8 +706,15 @@ fhandler_pty_slave::fhandler_pty_slave (int unit)
 fhandler_pty_slave::~fhandler_pty_slave ()
 {
   if (!get_ttyp ())
-    /* Why comes here? Who clears _tc? */
-    return;
+    {
+      /* Why comes here? Who clears _tc? */
+      if (freeconsole_on_close)
+	{
+	  FreeConsole ();
+	  pcon_attached_to = -1;
+	}
+      return;
+    }
   if (get_pseudo_console ())
     {
       int used = 0;