+static bool
+dri2_drm_config_is_compatible(struct dri2_egl_display *dri2_dpy,
+ const __DRIconfig *config,
+ struct gbm_surface *surface)
+{
+ const struct gbm_dri_visual *visual = NULL;
+ unsigned int red, green, blue, alpha;
+ int i;
+
+ /* Check that the EGLConfig being used to render to the surface is
+ * compatible with the surface format. Since mixing ARGB and XRGB of
+ * otherwise-compatible formats is relatively common, explicitly allow
+ * this.
+ */
+ dri2_dpy->core->getConfigAttrib(config, __DRI_ATTRIB_RED_MASK, &red);
+ dri2_dpy->core->getConfigAttrib(config, __DRI_ATTRIB_GREEN_MASK, &green);
+ dri2_dpy->core->getConfigAttrib(config, __DRI_ATTRIB_BLUE_MASK, &blue);
+ dri2_dpy->core->getConfigAttrib(config, __DRI_ATTRIB_ALPHA_MASK, &alpha);
+
+ for (i = 0; i < dri2_dpy->gbm_dri->num_visuals; i++) {
+ visual = &dri2_dpy->gbm_dri->visual_table[i];
+ if (visual->gbm_format == surface->format)
+ break;
+ }
+
+ if (i == dri2_dpy->gbm_dri->num_visuals)
+ return false;
+
+ if (red != visual->rgba_masks.red ||
+ green != visual->rgba_masks.green ||
+ blue != visual->rgba_masks.blue ||
+ (alpha && visual->rgba_masks.alpha && alpha != visual->rgba_masks.alpha)) {
+ return false;
+ }
+
+ return true;
+}
+