[PATCH 5/5] Xephyr: Fix broken image when endianess of client machine and host-Xserver differ

Egbert Eich eich at freedesktop.org
Tue Mar 31 00:14:29 PDT 2015


The image is created in the native byte order of the machine Xephyr is
rendered on however drawn in the image byte order of the Xephyr server.
Correct byte order in the xcb_image_t structure and convert to native
before updating the window.
If depths of Xephyr and host server differ this is already taken care of
by the depth conversion routine.
It is a terrible wase to always convert and transmit the entire image
no matter of the size of the damaged area. One should probably use
sub-images here. For now we leave this as an exercise.

Signed-off-by: Egbert Eich <eich at freedesktop.org>
---
 hw/kdrive/ephyr/hostx.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/hw/kdrive/ephyr/hostx.c b/hw/kdrive/ephyr/hostx.c
index 99b7716..2c8f743 100644
--- a/hw/kdrive/ephyr/hostx.c
+++ b/hw/kdrive/ephyr/hostx.c
@@ -866,6 +866,11 @@ hostx_screen_init(KdScreenInfo *screen,
                                                     ~0,
                                                     NULL);
 
+        /* Match server byte order so that the image can be converted to
+         * the native byte order by xcb_image_put() before drawing */
+        if (host_depth_matches_server(scrpriv))
+            scrpriv->ximg->byte_order = IMAGE_BYTE_ORDER;
+
         scrpriv->ximg->data =
             malloc(scrpriv->ximg->stride * buffer_height);
     }
@@ -1034,8 +1039,11 @@ hostx_paint_rect(KdScreenInfo *screen,
                           sx, sy, dx, dy, width, height, FALSE);
     }
     else {
-        xcb_image_put(HostX.conn, scrpriv->win, HostX.gc, scrpriv->ximg,
-                      0, 0, 0);
+        /* This is slow and could be done better */
+        xcb_image_t *img = xcb_image_native (HostX.conn, scrpriv->ximg, 1);
+        xcb_image_put(HostX.conn, scrpriv->win, HostX.gc, img, 0, 0, 0);
+        if (scrpriv->ximg != img)
+            xcb_image_destroy(img);
     }
 
     xcb_aux_sync(HostX.conn);
-- 
1.8.4.5



More information about the xorg-devel mailing list