Cygwin: console: Abort read() on signal if SA_RESTART is not set.

- Currently, console read() keeps reading after SIGWINCH is sent
  even if SA_RESTART flag is not set. With this patch, read()
  returns EINTR on SIGWINCH if SA_RESTART flag is not set.
  The same problem for SIGQUIT and SIGTSTP has also been fixed.

winsup/cygwin/fhandler_console.cc

@@ -586,12 +586,11 @@ wait_retry:
 	case input_ok: /* input ready */
 	  break;
 	case input_signalled: /* signalled */
-	  release_input_mutex ();
-	  /* The signal will be handled by cygwait() above. */
-	  continue;
 	case input_winch:
 	  release_input_mutex ();
-	  continue;
+	  if (global_sigs[get_ttyp ()->last_sig].sa_flags & SA_RESTART)
+	    continue;
+	  goto sig_exit;
 	default:
 	  /* Should not come here */
 	  release_input_mutex ();

winsup/cygwin/fhandler_termios.cc

@@ -133,6 +133,7 @@ tty_min::kill_pgrp (int sig)
   siginfo_t si = {0};
   si.si_signo = sig;
   si.si_code = SI_KERNEL;
+  last_sig = sig;
 
   for (unsigned i = 0; i < pids.npids; i++)
     {

winsup/cygwin/tty.cc

@@ -251,6 +251,7 @@ tty::init ()
   master_is_running_as_service = false;
   req_xfer_input = false;
   pcon_input_state = to_cyg;
+  last_sig = 0;
 }
 
 HANDLE

winsup/cygwin/tty.h

@@ -48,6 +48,7 @@ public:
   fh_devices ntty;
   ULONGLONG last_ctrl_c;	/* tick count of last ctrl-c */
   bool is_console;
+  int last_sig;
 
   IMPLEMENT_STATUS_FLAG (bool, initialized)
   IMPLEMENT_STATUS_FLAG (bool, rstcons)