VNC: Add framework to support a framebuffer driver interface

graphics/vnc/server/Kconfig

@@ -12,4 +12,20 @@ menuconfig VNCSERVER
 
 if VNCSERVER
 
+config VNCSERVER_NDISPLAYS
+	int "Number of displays"
+	default 1
+	range 1 99
+	---help---
+		Specifies the number of RFB displays supported by the server.
+		Normally this should be one.
+
+config VNCSERVER_PRIO
+	int "VNC server thread priority"
+	default 100
+
+config VNCSERVER_STACKSIZE
+	int "VNC server stack size"
+	default 2048
+
 endif # VNCSERVER

graphics/vnc/server/Make.defs

@@ -35,7 +35,7 @@
 
 ifeq ($(CONFIG_VNCSERVER),y)
 
-CSRCS += vnc_server.c vnc_session.c
+CSRCS += vnc_server.c vnc_session.c vnc_fbdev.c
 
 DEPPATH += --dep-path vnc/server
 CFLAGS += ${shell $(INCDIR) $(INCDIROPT) "$(CC)" $(TOPDIR)/graphics/vnc/server}

graphics/vnc/server/vnc_server.c

@@ -45,6 +45,16 @@
 
 #include "vnc_server.h"
 
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+/* Given a display number as an index, the following array can be used to
+ * look-up the session structure for that display.
+ */
+
+static FAR struct vnc_session_s *g_vnc_sessions[RFB_MAX_DISPLAYS];
+
 /****************************************************************************
  * Pubic Functions
  ****************************************************************************/
@@ -95,6 +105,8 @@ int vnc_server(int argc, FAR char *argv[])
       return EXIT_FAILURE;
     }
 
+  g_vnc_sessions[display] = session;
+
   /* Loop... handling each each VNC client connection to this display.  Only
    * a single client is allowed for each display.
    */
@@ -120,3 +132,34 @@ int vnc_server(int argc, FAR char *argv[])
 
   return EXIT_FAILURE; /* We won't get here */
 }
+
+/****************************************************************************
+ * Name: vnc_find_session
+ *
+ * Description:
+ *  Return the session structure associated with this display.
+ *
+ * Input Parameters:
+ *   display - The display number of interest.
+ *
+ * Returned Value:
+ *   Returns the instance of the session structure allocated by
+ *   vnc_create_session() for this display.  NULL will be returned if the
+ *   server has not yet been started or if the display number is out of
+ *   range.
+ *
+ ****************************************************************************/
+
+FAR struct vnc_session_s *vnc_find_session(int display)
+{
+  FAR struct vnc_session_s *session = NULL;
+
+  DEBUGASSERT(display >= 0 && display < RFB_MAX_DISPLAYS);
+
+  if (display >= 0 && display < RFB_MAX_DISPLAYS)
+    {
+      session = &g_vnc_sessions[display];
+    }
+
+  return session;
+}

graphics/vnc/server/vnc_server.h

@@ -52,11 +52,24 @@
 /****************************************************************************
  * Pre-processor Definitions
  ****************************************************************************/
+/* Configuration */
+
+#ifndef CONFIG_VNCSERVER_NDISPLAYS
+#  define CONFIG_VNCSERVER_NDISPLAYS 1
+#endif
+
+#ifndef CONFIG_VNCSERVER_PRIO
+#  define CONFIG_VNCSERVER_PRIO 100
+#endif
+
+#ifndef CONFIG_VNCSERVER_STACKSIZE
+#  define CONFIG_VNCSERVER_STACKSIZE 2048
+#endif
 
 /* RFB Port Number */
 
 #define RFB_PORT_BASE       5900
-#define RFB_MAX_DISPLAYS    100
+#define RFB_MAX_DISPLAYS    CONFIG_VNCSERVER_NDISPLAYS
 #define RFB_DISPLAY_PORT(d) (RFB_PORT_BASE + (d))
 
 /****************************************************************************
@@ -99,6 +112,30 @@ struct vnc_session_s
  * Public Function Prototypes
  ****************************************************************************/
 
+#ifdef __cplusplus
+#define EXTERN extern "C"
+extern "C"
+{
+#else
+#define EXTERN extern
+#endif
+
+/****************************************************************************
+ * Name: vnc_server
+ *
+ * Description:
+ *  The VNC server daemon.  This daemon is implemented as a kernel thread.
+ *
+ * Input Parameters:
+ *   Standard kernel thread arguments (all ignored)
+ *
+ * Returned Value:
+ *   This function does not return.
+ *
+ ****************************************************************************/
+
+int vnc_server(int argc, FAR char *argv[]);
+
 /****************************************************************************
  * Name: vnc_connect
  *
@@ -170,4 +207,28 @@ void vnc_release_session(FAR struct vnc_session_s *session);
 
 int vnc_session(FAR struct vnc_session_s *session);
 
+/****************************************************************************
+ * Name: vnc_find_session
+ *
+ * Description:
+ *  Return the session structure associated with this display.
+ *
+ * Input Parameters:
+ *   display - The display number of interest.
+ *
+ * Returned Value:
+ *   Returns the instance of the session structure allocated by
+ *   vnc_create_session() for this display.  NULL will be returned if the
+ *   server has not yet been started or if the display number is out of
+ *   range.
+ *
+ ****************************************************************************/
+
+FAR struct vnc_session_s *vnc_find_session(int display);
+
+#undef EXTERN
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* __GRAPHICS_VNC_SERVER_VNC_SERVER_H */