st/dri: add note about GL interop version checks

... and make them more explicit.

Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Tested-by: Tom Stellard <thomas.stellard@amd.com>

diff --git a/src/gallium/state_trackers/dri/dri2.c b/src/gallium/state_trackers/dri/dri2.c
index 8b6af60..15e3443 100644 (file)
--- a/src/gallium/state_trackers/dri/dri2.c
+++ b/src/gallium/state_trackers/dri/dri2.c
@@ -1468,7 +1468,8 @@ dri2_interop_query_device_info(__DRIcontext *_ctx,
 {
    struct pipe_screen *screen = dri_context(_ctx)->st->pipe->screen;
 
-   if (!out->version)
+   /* There is no version 0, thus we do not support it */
+   if (out->version == 0)
       return MESA_GLINTEROP_INVALID_VERSION;
 
    out->pci_segment_group = screen->get_param(screen, PIPE_CAP_PCI_GROUP);
@@ -1497,7 +1498,8 @@ dri2_interop_export_object(__DRIcontext *_ctx,
    unsigned target, usage;
    boolean success;
 
-   if (!in->version || !out->version)
+   /* There is no version 0, thus we do not support it */
+   if (in->version == 0 || out->version == 0)
       return MESA_GLINTEROP_INVALID_VERSION;
 
    /* Validate the target. */