+static int vnc_refresh_server_surface(VncDisplay *vd)
+{
+ int y;
+ uint8_t *guest_row;
+ uint8_t *server_row;
+ int cmp_bytes;
+ uint32_t width_mask[VNC_DIRTY_WORDS];
+ VncState *vs = NULL;
+ int has_dirty = 0;
+
+ /*
+ * Walk through the guest dirty map.
+ * Check and copy modified bits from guest to server surface.
+ * Update server dirty map.
+ */
+ vnc_set_bits(width_mask, (ds_get_width(vd->ds) / 16), VNC_DIRTY_WORDS);
+ cmp_bytes = 16 * ds_get_bytes_per_pixel(vd->ds);
+ guest_row = vd->guest.ds->data;
+ server_row = vd->server->data;
+ for (y = 0; y < vd->guest.ds->height; y++) {
+ if (vnc_and_bits(vd->guest.dirty[y], width_mask, VNC_DIRTY_WORDS)) {
+ int x;
+ uint8_t *guest_ptr;
+ uint8_t *server_ptr;
+
+ guest_ptr = guest_row;
+ server_ptr = server_row;
+
+ for (x = 0; x < vd->guest.ds->width;
+ x += 16, guest_ptr += cmp_bytes, server_ptr += cmp_bytes) {
+ if (!vnc_get_bit(vd->guest.dirty[y], (x / 16)))
+ continue;
+ vnc_clear_bit(vd->guest.dirty[y], (x / 16));
+ if (memcmp(server_ptr, guest_ptr, cmp_bytes) == 0)
+ continue;
+ memcpy(server_ptr, guest_ptr, cmp_bytes);
+ vs = vd->clients;
+ while (vs != NULL) {
+ vnc_set_bit(vs->dirty[y], (x / 16));
+ vs = vs->next;
+ }
+ has_dirty++;
+ }
+ }
+ guest_row += ds_get_linesize(vd->ds);
+ server_row += ds_get_linesize(vd->ds);
+ }
+ return has_dirty;
+}
+
+static void vnc_refresh(void *opaque)
+{
+ VncDisplay *vd = opaque;
+ VncState *vs = NULL;
+ int has_dirty = 0, rects = 0;
+
+ vga_hw_update();
+
+ has_dirty = vnc_refresh_server_surface(vd);
+
+ vs = vd->clients;
+ while (vs != NULL) {
+ rects += vnc_update_client(vs, has_dirty);
+ vs = vs->next;
+ }
+
+ if (has_dirty && rects) {
+ vd->timer_interval /= 2;
+ if (vd->timer_interval < VNC_REFRESH_INTERVAL_BASE)
+ vd->timer_interval = VNC_REFRESH_INTERVAL_BASE;
+ } else {
+ vd->timer_interval += VNC_REFRESH_INTERVAL_INC;
+ if (vd->timer_interval > VNC_REFRESH_INTERVAL_MAX)
+ vd->timer_interval = VNC_REFRESH_INTERVAL_MAX;
+ }
+ qemu_mod_timer(vd->timer, qemu_get_clock(rt_clock) + vd->timer_interval);
+}
+
+static void vnc_init_timer(VncDisplay *vd)
+{
+ vd->timer_interval = VNC_REFRESH_INTERVAL_BASE;
+ if (vd->timer == NULL && vd->clients != NULL) {
+ vd->timer = qemu_new_timer(rt_clock, vnc_refresh, vd);
+ vnc_refresh(vd);
+ }
+}
+
+static void vnc_remove_timer(VncDisplay *vd)
+{
+ if (vd->timer != NULL && vd->clients == NULL) {
+ qemu_del_timer(vd->timer);
+ qemu_free_timer(vd->timer);
+ vd->timer = NULL;
+ }
+}
+