From f55fc99c77d8ace866a645fbce8b54a12accfa9f Mon Sep 17 00:00:00 2001
From: Corinna Vinschen <corinna@vinschen.de>
Date: Wed, 13 Jul 2011 18:59:41 +0000
Subject: [PATCH] 	* fhandler_serial.cc (fhandler_serial::raw_read):
 Handle non-blocking 	case more thoroughly.

---
 winsup/cygwin/ChangeLog          |  5 +++++
 winsup/cygwin/fhandler_serial.cc | 22 +++++++++++++++++++++-
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 64347c435..0839a5fef 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,8 @@
+2011-07-13  Corinna Vinschen  <corinna@vinschen.de>
+
+	* fhandler_serial.cc (fhandler_serial::raw_read): Handle non-blocking
+	case more thoroughly.
+
 2011-07-13  Christopher Faylor  <me.cygwin2011@cgf.cx>
 
 	* setup_handler (setup_handler): Change break to goto out, missed in
diff --git a/winsup/cygwin/fhandler_serial.cc b/winsup/cygwin/fhandler_serial.cc
index f8c8ab5c6..24df7c386 100644
--- a/winsup/cygwin/fhandler_serial.cc
+++ b/winsup/cygwin/fhandler_serial.cc
@@ -81,7 +81,17 @@ fhandler_serial::raw_read (void *ptr, size_t& ulen)
 	    }
 	  else if (GetLastError () != ERROR_IO_PENDING)
 	    goto err;
-	  else if (!is_nonblocking ())
+	  else if (is_nonblocking ())
+	    {
+	      PurgeComm (get_handle (), PURGE_RXABORT);
+	      if (tot == 0)
+		{
+		  tot = -1;
+		  set_errno (EAGAIN);
+		}
+	      goto out;
+	    }
+	  else
 	    {
 	      HANDLE w4[3] = { io_status.hEvent, signal_arrived,
 			       pthread::get_cancel_event () };
@@ -124,6 +134,16 @@ restart:
 	/* Got something */;
       else if (GetLastError () != ERROR_IO_PENDING)
 	goto err;
+      else if (is_nonblocking ())
+	{
+	  PurgeComm (get_handle (), PURGE_RXABORT);
+	  if (tot == 0)
+	    {
+	      tot = -1;
+	      set_errno (EAGAIN);
+	    }
+	  goto out;
+	}
       else if (!GetOverlappedResult (get_handle (), &io_status, &n, TRUE))
 	goto err;