* fhandler.h (fhandler_base::get_echo_handle): New virtual method.

	(class fhandler_pty_master): Add echo_r and echo_w handles constituting
	read and write side of new echo pipe.
	* select.cc (peek_pipe): On pty masters, check additionally if input
	from the echo pipe is available.
	* fhandler_tty.cc (fhandler_pty_master::doecho): Drop output_mutex
	locking.  Write output to echo pipe.
	(fhandler_pty_master::process_slave_output): Check if input is available
	in echo pipe and prefer to read from it, if so.
	(fhandler_pty_slave::write): Drop output_mutex locking.
	(fhandler_pty_master::fhandler_pty_master): Initialize echo pipe
	handles to NULL.
	(fhandler_pty_master::close): Close and NULL echo pipe handles.
	(fhandler_pty_master::setup): Create echo pipe, close in case of error.

1 files changed, 3 insertions, 0 deletions

diff --git a/winsup/cygwin/fhandler.h b/winsup/cygwin/fhandler.h
index 10eacd106..4ec7d02fa 100644
--- a/winsup/cygwin/fhandler.h
+++ b/winsup/cygwin/fhandler.h
@@ -414,6 +414,7 @@ public:
   virtual HANDLE& get_io_handle () { return io_handle; }
   virtual HANDLE& get_output_handle () { return io_handle; }
   virtual HANDLE get_stat_handle () { return pc.handle () ?: io_handle; }
+  virtual HANDLE get_echo_handle () const { return NULL; }
   virtual bool hit_eof () {return false;}
   virtual select_record *select_read (select_stuff *);
   virtual select_record *select_write (select_stuff *);
@@ -1569,11 +1570,13 @@ class fhandler_pty_master: public fhandler_pty_common
   HANDLE master_ctl;		// Control socket for handle duplication
   cygthread *master_thread;	// Master control thread
   HANDLE from_master, to_master;
+  HANDLE echo_r, echo_w;
   DWORD dwProcessId;		// Owner of master handles
 
 public:
   int need_nl;			// Next read should start with \n
 
+  HANDLE get_echo_handle () const { return echo_r; }
   /* Constructor */
   fhandler_pty_master (int);