Only allocate a buffer if the format doesn't require a specific type

If there's a specified type but that type doesn't provide a buffer, we
return an error, currently GST_FLOW_ERROR_NOT_SUPPORTED, but that might
change in the future.

1 files changed, 7 insertions, 2 deletions

diff --git a/gst-libs/gst/cairo/gstcairopad.c b/gst-libs/gst/cairo/gstcairopad.c
index 3a0ce71..9cbaadb 100644
--- a/gst-libs/gst/cairo/gstcairopad.c
+++ b/gst-libs/gst/cairo/gstcairopad.c
@@ -162,8 +162,13 @@ gst_cairo_pad_alloc_buffer_full (GstPad * pad,
     gst_caps_unref (caps);
   }
   if (*buffer == NULL) {
-    *buffer = gst_cairo_buffer_new (format);
-    gst_buffer_set_caps (*buffer, caps);
+    if (gst_cairo_format_get_surface_type (format) == CAIRO_SURFACE_TYPE_IMAGE) {
+      *buffer = gst_cairo_buffer_new (format);
+      gst_buffer_set_caps (*buffer, caps);
+    } else {
+      /* FIXME: get a good error here */
+      ret = GST_FLOW_NOT_SUPPORTED;
+    }
   } else if (!gst_cairo_format_is_native (format)) {
     /* We need to clear the buffer to keep Cairo's guarantee that new
      * surfaces are memset to zero.