[PATCH] ephyr: Fix crash on 24bpp host framebuffer

[Daniel Martin]

Use bytes_per_line and bits_per_pixel from the created XImage to fix
    https://bugzilla.redhat.com/show_bug.cgi?id=518960
---

Just encountered this bug. It was reported in 2009 and updated in 2011
for the last time. But, it didn't made it upstream. 

This is a slightly modified version of the last patch Daniel Stone
wrote. The difference is, that it gets bits_per_pixel from the XImage
too.


 hw/kdrive/ephyr/ephyr.c |    6 ++----
 hw/kdrive/ephyr/hostx.c |    6 +++++-
 hw/kdrive/ephyr/hostx.h |    3 ++-
 3 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/hw/kdrive/ephyr/ephyr.c b/hw/kdrive/ephyr/ephyr.c
index 109c599..82fb744 100644
--- a/hw/kdrive/ephyr/ephyr.c
+++ b/hw/kdrive/ephyr/ephyr.c
@@ -238,13 +238,11 @@ ephyrMapFramebuffer(KdScreenInfo * screen)
     KdComputePointerMatrix(&m, ephyrRandr, screen->width, screen->height);
     KdSetPointerMatrix(&m);
 
-    priv->bytes_per_line =
-        ((screen->width * screen->fb.bitsPerPixel + 31) >> 5) << 2;
-
     buffer_height = ephyrBufferHeight(screen);
 
     priv->base =
-        hostx_screen_init(screen, screen->width, screen->height, buffer_height);
+        hostx_screen_init(screen, screen->width, screen->height, buffer_height,
+                          &priv->bytes_per_line, &screen->fb.bitsPerPixel);
 
     if ((scrpriv->randr & RR_Rotate_0) && !(scrpriv->randr & RR_Reflect_All)) {
         scrpriv->shadow = FALSE;
diff --git a/hw/kdrive/ephyr/hostx.c b/hw/kdrive/ephyr/hostx.c
index 50e94fa..53382f1 100644
--- a/hw/kdrive/ephyr/hostx.c
+++ b/hw/kdrive/ephyr/hostx.c
@@ -622,7 +622,8 @@ hostx_set_cmap_entry(unsigned char idx,
  */
 void *
 hostx_screen_init(EphyrScreenInfo screen,
-                  int width, int height, int buffer_height)
+                  int width, int height, int buffer_height,
+                  int *bytes_per_line, int *bits_per_pixel)
 {
     int bitmap_pad;
     Bool shm_success = False;
@@ -699,6 +700,9 @@ hostx_screen_init(EphyrScreenInfo screen,
             malloc(host_screen->ximg->bytes_per_line * buffer_height);
     }
 
+    *bytes_per_line = host_screen->ximg->bytes_per_line;
+    *bits_per_pixel = host_screen->ximg->bits_per_pixel;
+
     XResizeWindow(HostX.dpy, host_screen->win, width, height);
 
     /* Ask the WM to keep our size static */
diff --git a/hw/kdrive/ephyr/hostx.h b/hw/kdrive/ephyr/hostx.h
index 31c4053..38b7b37 100644
--- a/hw/kdrive/ephyr/hostx.h
+++ b/hw/kdrive/ephyr/hostx.h
@@ -193,7 +193,8 @@ hostx_set_cmap_entry(unsigned char idx,
                      unsigned char r, unsigned char g, unsigned char b);
 
 void *hostx_screen_init(EphyrScreenInfo screen,
-                        int width, int height, int buffer_height);
+                        int width, int height, int buffer_height,
+                        int *bytes_per_line, int *bits_per_pixel);
 
 void
 
-- 
1.7.2.5