[newlib-cygwin/cygwin-3_3-branch] Cygwin: console: Retain ENABLE_VIRTUAL_TERMIANL_PROCESSING flag.

[Takashi Yano <tyan0@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=e4fdb0cb73cc48a2db473b525b6ba0a33ecabf97

commit e4fdb0cb73cc48a2db473b525b6ba0a33ecabf97
Author: Takashi Yano <takashi.yano@nifty.ne.jp>
Date:   Tue Jun 14 21:01:58 2022 +0900

    Cygwin: console: Retain ENABLE_VIRTUAL_TERMIANL_PROCESSING flag.
    
    - Currently, ENABLE_VIRTUAL_TERMINAL_PROCESSING flag is disabled
      unconditionally when exiting from cygwin. This causes ANSI escape
      sequence disabled in Windows Terminal where it is enables by
      default. This patch retains that flag if it is originally enabled.

Diff:
---
 winsup/cygwin/fhandler.h          | 1 +
 winsup/cygwin/fhandler_console.cc | 4 ++++
 2 files changed, 5 insertions(+)

diff --git a/winsup/cygwin/fhandler.h b/winsup/cygwin/fhandler.h
index 2ff99aeae..9940da771 100644
--- a/winsup/cygwin/fhandler.h
+++ b/winsup/cygwin/fhandler.h
@@ -2021,6 +2021,7 @@ class dev_console
 {
   pid_t owner;
   bool is_legacy;
+  bool orig_virtual_terminal_processing_mode;
 
   WORD default_color, underline_color, dim_color;
 
diff --git a/winsup/cygwin/fhandler_console.cc b/winsup/cygwin/fhandler_console.cc
index e84823685..5adf0b8e4 100644
--- a/winsup/cygwin/fhandler_console.cc
+++ b/winsup/cygwin/fhandler_console.cc
@@ -596,6 +596,8 @@ fhandler_console::set_output_mode (tty::cons_mode m, const termios *t,
 				   const handle_set_t *p)
 {
   DWORD flags = ENABLE_PROCESSED_OUTPUT | ENABLE_WRAP_AT_EOL_OUTPUT;
+  if (con.orig_virtual_terminal_processing_mode)
+    flags |= ENABLE_VIRTUAL_TERMINAL_PROCESSING;
   WaitForSingleObject (p->output_mutex, mutex_timeout);
   switch (m)
     {
@@ -1503,6 +1505,8 @@ fhandler_console::open (int flags, mode_t)
       /* Check xterm compatible mode in output */
       acquire_attach_mutex (mutex_timeout);
       GetConsoleMode (get_output_handle (), &dwMode);
+      con.orig_virtual_terminal_processing_mode =
+	!!(dwMode & ENABLE_VIRTUAL_TERMINAL_PROCESSING);
       if (!SetConsoleMode (get_output_handle (),
 			   dwMode | ENABLE_VIRTUAL_TERMINAL_PROCESSING))
 	is_legacy = true;