Add a simple example for the TCLO protocol support in vmbackdoor.

examples/backdoor-tclo/Makefile

@@ -0,0 +1,6 @@
+TARGET = backdoor-tclo.img
+
+APP_SOURCES = main.c
+
+LIB_DIR = ../../lib
+include $(LIB_DIR)/Makefile.rules

examples/backdoor-tclo/main.c

@@ -0,0 +1,57 @@
+/*
+ * Example for receiving TCLO commands, polled from the host.
+ * These are used for asynchronous host-to-guest messages,
+ * like resolution changes and clipboard synchronization.
+ * 
+ * (These commands are actually part of VMware Tools, not the
+ * SVGA device. They're documented and implemented far better
+ * in the open-vm-tools project. However, we include a very tiny
+ * implemnentation here in order to test features which involve
+ * collaboration between Tools and SVGA, like Unity or Fit-Guest.)
+ *
+ * This sample just writes all incoming and outgoing messages to the
+ * console.
+ */
+
+#include "intr.h"
+#include "console_vga.h"
+#include "vmbackdoor.h"
+#include "timer.h"
+#include "svga.h"
+
+void
+sendCapabilities(void)
+{
+   VMBackdoor_RPCString("tools.capability.resolution_set 1");
+   VMBackdoor_RPCString("tools.capability.resolution_server toolbox 1");
+   VMBackdoor_RPCString("tools.capability.display_topology_set 1");
+   VMBackdoor_RPCString("tools.capability.color_depth_set 1");
+   VMBackdoor_RPCString("tools.capability.resolution_min 0 0");
+   VMBackdoor_RPCString("tools.capability.unity 1");
+}
+
+int
+main(void)
+{
+   static VMTCLOState tclo;
+
+   Intr_Init();
+   Intr_SetFaultHandlers(Console_UnhandledFault);
+   ConsoleVGA_Init();
+
+   /* Use the PIT to set TCLO polling rate. */
+   Timer_InitPIT(PIT_HZ / 30);
+   Intr_SetMask(0, TRUE);
+
+   sendCapabilities();
+
+   while (1) {
+      Intr_Halt();
+
+      if (VMBackdoor_PollTCLO(&tclo, TRUE)) {
+         VMBackdoor_ReplyTCLO(&tclo, TCLO_UNKNOWN_CMD);
+      }
+   }
+
+   return 0;
+}