Add framework to support framebuffer/security negotiation

graphics/vnc/server/Kconfig

@@ -12,6 +12,19 @@ menuconfig VNCSERVER
 
 if VNCSERVER
 
+choice
+	prompt "VNC server protocol"
+	default VNCSERVER_PROTO3p3
+
+config VNCSERVER_PROTO3p3
+	bool "Version 3.3"
+
+config VNCSERVER_PROTO3p3
+	bool "Version 3.8"
+	depends on EXPERIMENTAL
+
+endchoice # VNC server protocol
+
 config VNCSERVER_NDISPLAYS
 	int "Number of displays"
 	default 1

graphics/vnc/server/Make.defs

@@ -35,7 +35,7 @@
 
 ifeq ($(CONFIG_VNCSERVER),y)
 
-CSRCS += vnc_server.c vnc_session.c vnc_fbdev.c
+CSRCS += vnc_server.c vnc_session.c vnc_negotiate.c vnc_fbdev.c
 
 ifeq ($(CONFIG_NX_KBD),y)
 CSRCS += vnc_keymap.c

graphics/vnc/server/vnc_negotiate.c

@@ -0,0 +1,105 @@
+/****************************************************************************
+ * graphics/vnc/vnc_negotiate.c
+ *
+ *   Copyright (C) 2016 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <stdint.h>
+#include <string.h>
+#include <errno.h>
+
+#include <nuttx/video/rfb.h>
+
+#include "vnc_server.h"
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: nvc_xyz
+ *
+ * Description:
+ *  [Re-]initialize a VNC session
+ *
+ * Input Parameters:
+ *   session - the VNC session to be initialized
+ *
+ * Returned Value:
+ *   None
+ *
+ ****************************************************************************/
+
+static void nvc_xyz(FAR struct vnc_session_s *session)
+{
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: vnc_negotiate
+ *
+ * Description:
+ *  Perform the VNC initialize sequency after a client has sucessfully
+ *  connected to the server.  Negotiate security, framebuffer and color
+ *  properties.
+ *
+ * Input Parameters:
+ *   session - An instance of the session structure allocated by
+ *     vnc_create_session().
+ *
+ * Returned Value:
+ *   Returns zero (OK) on success; a negated errno value on failure.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_VNCSERVER_PROTO3p3
+int vnc_negotiate(FAR struct vnc_session_s *session)
+{
+  return OK;
+}
+#endif
+
+#ifdef CONFIG_VNCSERVER_PROTO3p8
+int vnc_negotiate(FAR struct vnc_session_s *session)
+{
+  return OK;
+}
+#endif

graphics/vnc/server/vnc_server.h

@@ -52,8 +52,17 @@
 /****************************************************************************
  * Pre-processor Definitions
  ****************************************************************************/
+
 /* Configuration */
 
+#if !defined(CONFIG_VNCSERVER_PROTO3p3) && !defined(CONFIG_VNCSERVER_PROTO3p8)
+#  error No VNC protocol selected
+#endif
+
+#if defined(CONFIG_VNCSERVER_PROTO3p3) && defined(CONFIG_VNCSERVER_PROTO3p8)
+#  error Too many VNC protocols selected
+#endif
+
 #ifndef CONFIG_VNCSERVER_NDISPLAYS
 #  define CONFIG_VNCSERVER_NDISPLAYS 1
 #endif