vnc: Support for LED state extension

Signed-off-by: NLei Li <lilei@linux.vnet.ibm.com>
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Message-id: 1366867752-11578-3-git-send-email-lilei@linux.vnet.ibm.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

ui/vnc.c

@@ -1522,6 +1522,42 @@ static void press_key(VncState *vs, int keysym)
     kbd_put_keycode(keycode | SCANCODE_UP);
 }
 
+static int current_led_state(VncState *vs)
+{
+    int ledstate = 0;
+
+    if (vs->modifiers_state[0x46]) {
+        ledstate |= QEMU_SCROLL_LOCK_LED;
+    }
+    if (vs->modifiers_state[0x45]) {
+        ledstate |= QEMU_NUM_LOCK_LED;
+    }
+    if (vs->modifiers_state[0x3a]) {
+        ledstate |= QEMU_CAPS_LOCK_LED;
+    }
+
+    return ledstate;
+}
+
+static void vnc_led_state_change(VncState *vs)
+{
+    int ledstate = 0;
+
+    if (!vnc_has_feature(vs, VNC_FEATURE_LED_STATE)) {
+        return;
+    }
+
+    ledstate = current_led_state(vs);
+    vnc_lock_output(vs);
+    vnc_write_u8(vs, VNC_MSG_SERVER_FRAMEBUFFER_UPDATE);
+    vnc_write_u8(vs, 0);
+    vnc_write_u16(vs, 1);
+    vnc_framebuffer_update(vs, 0, 0, 1, 1, VNC_ENCODING_LED_STATE);
+    vnc_write_u8(vs, ledstate);
+    vnc_unlock_output(vs);
+    vnc_flush(vs);
+}
+
 static void kbd_leds(void *opaque, int ledstate)
 {
     VncState *vs = opaque;
@@ -1540,6 +1576,11 @@ static void kbd_leds(void *opaque, int ledstate)
     if (vs->modifiers_state[0x46] != scr) {
         vs->modifiers_state[0x46] = scr;
     }
+
+    /* Sending the current led state message to the client */
+    if (ledstate != current_led_state(vs)) {
+        vnc_led_state_change(vs);
+    }
 }
 
 static void do_key_event(VncState *vs, int down, int keycode, int sym)
@@ -1893,6 +1934,9 @@ static void set_encodings(VncState *vs, int32_t *encodings, size_t n_encodings)
         case VNC_ENCODING_WMVi:
             vs->features |= VNC_FEATURE_WMVI_MASK;
             break;
+        case VNC_ENCODING_LED_STATE:
+            vs->features |= VNC_FEATURE_LED_STATE_MASK;
+            break;
         case VNC_ENCODING_COMPRESSLEVEL0 ... VNC_ENCODING_COMPRESSLEVEL0 + 9:
             vs->tight.compression = (enc & 0x0F);
             break;
@@ -1908,6 +1952,7 @@ static void set_encodings(VncState *vs, int32_t *encodings, size_t n_encodings)
     }
     vnc_desktop_resize(vs);
     check_pointer_type_change(&vs->mouse_mode_notifier, NULL);
+    vnc_led_state_change(vs);
 }
 
 static void set_pixel_conversion(VncState *vs)

ui/vnc.h

@@ -384,6 +384,7 @@ enum {
 #define VNC_ENCODING_EXT_KEY_EVENT        0XFFFFFEFE /* -258 */
 #define VNC_ENCODING_AUDIO                0XFFFFFEFD /* -259 */
 #define VNC_ENCODING_TIGHT_PNG            0xFFFFFEFC /* -260 */
+#define VNC_ENCODING_LED_STATE            0XFFFFFEFB /* -261 */
 #define VNC_ENCODING_WMVi                 0x574D5669
 
 /*****************************************************************************
@@ -422,6 +423,7 @@ enum {
 #define VNC_FEATURE_TIGHT_PNG                8
 #define VNC_FEATURE_ZRLE                     9
 #define VNC_FEATURE_ZYWRLE                  10
+#define VNC_FEATURE_LED_STATE               11
 
 #define VNC_FEATURE_RESIZE_MASK              (1 << VNC_FEATURE_RESIZE)
 #define VNC_FEATURE_HEXTILE_MASK             (1 << VNC_FEATURE_HEXTILE)
@@ -434,6 +436,7 @@ enum {
 #define VNC_FEATURE_TIGHT_PNG_MASK           (1 << VNC_FEATURE_TIGHT_PNG)
 #define VNC_FEATURE_ZRLE_MASK                (1 << VNC_FEATURE_ZRLE)
 #define VNC_FEATURE_ZYWRLE_MASK              (1 << VNC_FEATURE_ZYWRLE)
+#define VNC_FEATURE_LED_STATE_MASK           (1 << VNC_FEATURE_LED_STATE)
 
 
 /* Client -> Server message IDs */