[PATCH v2] Cygwin: console: Abort read() on signal if SA_RESTART is not set.

[Takashi Yano via Cygwin-patches]

- 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 | 7 +++----
 winsup/cygwin/fhandler_termios.cc | 1 +
 winsup/cygwin/tty.cc              | 1 +
 winsup/cygwin/tty.h               | 1 +
 4 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/winsup/cygwin/fhandler_console.cc 
b/winsup/cygwin/fhandler_console.cc
index 3c0783575..78af6cf2b 100644
--- a/winsup/cygwin/fhandler_console.cc
+++ b/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 ();
diff --git a/winsup/cygwin/fhandler_termios.cc 
b/winsup/cygwin/fhandler_termios.cc
index 9fbace95c..e8daf946b 100644
--- a/winsup/cygwin/fhandler_termios.cc
+++ b/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++)
     {
diff --git a/winsup/cygwin/tty.cc b/winsup/cygwin/tty.cc
index 41f81f694..7627cd6c7 100644
--- a/winsup/cygwin/tty.cc
+++ b/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
diff --git a/winsup/cygwin/tty.h b/winsup/cygwin/tty.h
index e1de7ab46..a8ddd68d6 100644
--- a/winsup/cygwin/tty.h
+++ b/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)
-- 
2.30.0