Bug#47571: idle named pipe connection is unkillable

Bug#31621: Windows server hanging during shutdown using named pipes 
           and idle connection
            
Problem: when idle pipe connection is forcefully closed with KILL
statement or when the server goes down, thread that is closing connection
would hang infinitely in CloseHandle(). The reason for the hang is that 
named pipe operations are performed synchronously. In this mode all IOs
on pipe are serialized, that is CloseHandle() will not abort ReadFile() 
in another thread, but wait for ReadFile() to complete.
            
The fix implements asynchrnous mode for named pipes, where operation of file
are not synchronized. Read/Write operation would fire an async IO and wait for
either IO completion or timeout.
            
Note, that with this patch timeouts are properly handled for named pipes.
      
Post-review: Win32 timeout code has been fixed for named pipes and shared
memory. We do not store pointer to NET in vio structure, only the read and 
write timeouts.

include/violite.h

@@ -44,7 +44,7 @@ enum enum_vio_type
 Vio*	vio_new(my_socket sd, enum enum_vio_type type, uint flags);
 #ifdef __WIN__
 Vio* vio_new_win32pipe(HANDLE hPipe);
-Vio* vio_new_win32shared_memory(NET *net,HANDLE handle_file_map,
+Vio* vio_new_win32shared_memory(HANDLE handle_file_map,
                                 HANDLE handle_map,
                                 HANDLE event_server_wrote,
                                 HANDLE event_server_read,
@@ -221,7 +221,11 @@ struct st_vio
   HANDLE  event_conn_closed;
   size_t  shared_memory_remain;
   char    *shared_memory_pos;
-  NET     *net;
 #endif /* HAVE_SMEM */
+#ifdef _WIN32
+  OVERLAPPED pipe_overlapped;
+  DWORD read_timeout_millis;
+  DWORD write_timeout_millis;
+#endif
 };
 #endif /* vio_violite_h_ */