ui/cocoa: Add format check for shared surfaces

Only share surfaces for specific pixman formats supported by equivalent
formats in CGImage. Probably more could be supported, but these are the
ones implemented right now and should match the common cases.

Signed-off-by: Rainer Müller <[email protected]>

Author: raimue

ui/cocoa.m

@@ -1103,6 +1103,16 @@ static void cocoa_refresh(DisplayChangeListener *dcl)
     [pool release];
 }
 
+static bool cocoa_check_format(DisplayChangeListener *dcl,
+                               pixman_format_code_t format)
+{
+    /* The only supported format is kCGImageAlphaNoneSkipFirst,
+     * for 32 and 16 bit
+     */
+    return format == PIXMAN_x8r8g8b8 ||
+           format == PIXMAN_x1r5g5b5;
+}
+
 static void cocoa_cleanup(void)
 {
     COCOA_DEBUG("qemu_cocoa: cocoa_cleanup\n");
@@ -1113,6 +1123,7 @@ static void cocoa_cleanup(void)
     .dpy_name          = "cocoa",
     .dpy_gfx_update = cocoa_update,
     .dpy_gfx_switch = cocoa_switch,
+    .dpy_gfx_check_format = cocoa_check_format,
     .dpy_refresh = cocoa_refresh,
 };