The extended desktop resize encoding adds support for (a) clients
sending resize requests to the server, and (b) multihead support.
This patch implements (a). All resize requests are rejected by qemu.
Qemu can't resize the framebuffer on its own, this is in the hands of
the guest, so all qemu can do is forward the request to the guest.
Should the guest actually resize the framebuffer we can notify the vnc
client later with a separate message.
This requires support in the display device. Works with virtio-gpu.
https://github.com/rfbproto/rfbproto/blob/master/rfbproto.rst#extendeddesktopsize-pseudo-encoding
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
ui/vnc.h | 2 ++
ui/vnc.c | 64 +++++++++++++++++++++++++++++++++++++++++++++++++++++++-
2 files changed, 65 insertions(+), 1 deletion(-)
diff --git a/ui/vnc.h b/ui/vnc.h
index c8d3ad9ec496..77a310947bd6 100644
--- a/ui/vnc.h
+++ b/ui/vnc.h
@@ -442,6 +442,7 @@ enum {
enum VncFeatures {
VNC_FEATURE_RESIZE,
+ VNC_FEATURE_RESIZE_EXT,
VNC_FEATURE_HEXTILE,
VNC_FEATURE_POINTER_TYPE_CHANGE,
VNC_FEATURE_WMVI,
@@ -456,6 +457,7 @@ enum VncFeatures {
};
#define VNC_FEATURE_RESIZE_MASK (1 << VNC_FEATURE_RESIZE)
+#define VNC_FEATURE_RESIZE_EXT_MASK (1 << VNC_FEATURE_RESIZE_EXT)
#define VNC_FEATURE_HEXTILE_MASK (1 << VNC_FEATURE_HEXTILE)
#define VNC_FEATURE_POINTER_TYPE_CHANGE_MASK (1 << VNC_FEATURE_POINTER_TYPE_CHANGE)
#define VNC_FEATURE_WMVI_MASK (1 << VNC_FEATURE_WMVI)
diff --git a/ui/vnc.c b/ui/vnc.c
index bdaf384f71a4..a15132faa96f 100644
--- a/ui/vnc.c
+++ b/ui/vnc.c
@@ -663,10 +663,35 @@ void vnc_framebuffer_update(VncState *vs, int x, int y, int w, int h,
vnc_write_s32(vs, encoding);
}
+static void vnc_desktop_resize_ext(VncState *vs, bool reject)
+{
+ vnc_lock_output(vs);
+ vnc_write_u8(vs, VNC_MSG_SERVER_FRAMEBUFFER_UPDATE);
+ vnc_write_u8(vs, 0);
+ vnc_write_u16(vs, 1); /* number of rects */
+ vnc_framebuffer_update(vs,
+ reject ? 1 : 0,
1 "The client receiving this message requested a change of the screen
layout. The change may or may not have happened depending on server
policy or available resources. The status code in the y-position
field must be used to determine which."
ok
0 "The screen layout was changed via non-RFB means on the server."
ok
+ reject ? 3 : 0,
3 "Invalid screen layout"
ok
+ vs->client_width, vs->client_height,
+ VNC_ENCODING_DESKTOP_RESIZE_EXT);
+ vnc_write_u8(vs, 1); /* number of screens */
+ vnc_write_u8(vs, 0); /* padding */
+ vnc_write_u8(vs, 0); /* padding */
+ vnc_write_u8(vs, 0); /* padding */
+ vnc_write_u32(vs, 0); /* screen id */
+ vnc_write_u16(vs, 0); /* screen x-pos */
+ vnc_write_u16(vs, 0); /* screen y-pos */
+ vnc_write_u16(vs, vs->client_width);
+ vnc_write_u16(vs, vs->client_height);
+ vnc_write_u32(vs, 0); /* screen flags */
+ vnc_unlock_output(vs);
+ vnc_flush(vs);
+}
static void vnc_desktop_resize(VncState *vs, bool force)
{
- if (vs->ioc == NULL || !vnc_has_feature(vs, VNC_FEATURE_RESIZE)) {
+ if (vs->ioc == NULL || (!vnc_has_feature(vs, VNC_FEATURE_RESIZE) &&
+ !vnc_has_feature(vs, VNC_FEATURE_RESIZE_EXT))) {
return;
}
if (vs->client_width == pixman_image_get_width(vs->vd->server) &&
@@ -681,6 +706,12 @@ static void vnc_desktop_resize(VncState *vs, bool force)
pixman_image_get_height(vs->vd->server) >= 0);
vs->client_width = pixman_image_get_width(vs->vd->server);
vs->client_height = pixman_image_get_height(vs->vd->server);
+
+ if (vnc_has_feature(vs, VNC_FEATURE_RESIZE_EXT)) {
+ vnc_desktop_resize_ext(vs, false);
+ return;
+ }
+
vnc_lock_output(vs);
vnc_write_u8(vs, VNC_MSG_SERVER_FRAMEBUFFER_UPDATE);
vnc_write_u8(vs, 0);
@@ -2110,6 +2141,9 @@ static void set_encodings(VncState *vs, int32_t *encodings, size_t n_encodings)
case VNC_ENCODING_DESKTOPRESIZE:
vs->features |= VNC_FEATURE_RESIZE_MASK;
break;
+ case VNC_ENCODING_DESKTOP_RESIZE_EXT:
+ vs->features |= VNC_FEATURE_RESIZE_EXT_MASK;
+ break;
case VNC_ENCODING_POINTER_TYPE_CHANGE:
vs->features |= VNC_FEATURE_POINTER_TYPE_CHANGE_MASK;
break;
@@ -2431,6 +2465,34 @@ static int protocol_client_msg(VncState *vs, uint8_t *data, size_t len)
break;
}
break;
+ case VNC_MSG_CLIENT_SET_DESKTOP_SIZE:
+ {
+ size_t size;
+ uint8_t screens;
+ uint16_t width;
+ uint16_t height;
+ QemuUIInfo info;
+
+ if (len < 8) {
+ return 8;
+ }
+
+ screens = read_u8(data, 6);
+ size = 8 + screens * 16;
+ if (len < size) {
+ return size;
+ }
Maybe leave a TODO note for handling multiple screens etc?
lgtm
+
+ width = read_u16(data, 2);
+ height = read_u16(data, 4);
+ vnc_desktop_resize_ext(vs, true);
+
+ memset(&info, 0, sizeof(info));
+ info.width = width;
+ info.height = height;
+ dpy_set_ui_info(vs->vd->dcl.con, &info);
+ break;
+ }
default:
VNC_DEBUG("Msg: %d\n", data[0]);
vnc_client_error(vs);
--
2.27.0