KnownObject: Make it an error to request ID 0
WebGPU error handling assumes non-optional objects point to valid
objects. The wire code wasn't updated to produce an error when ID 0 is
requested in the non-optional case.
BUG=chromium:934360
Change-Id: I203d2ec864dabe0e76109e1932fc31cbf26291d7
Reviewed-on: https://dawn-review.googlesource.com/c/4980
Reviewed-by: Austin Eng <enga@chromium.org>
Reviewed-by: Kai Ninomiya <kainino@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
diff --git a/src/dawn_wire/server/ObjectStorage.h b/src/dawn_wire/server/ObjectStorage.h
index 3405a88..0da9e7c 100644
--- a/src/dawn_wire/server/ObjectStorage.h
+++ b/src/dawn_wire/server/ObjectStorage.h
@@ -60,12 +60,14 @@
using Data = ObjectData<T>;
KnownObjects() {
- // Pre-allocate ID 0 to refer to the null handle.
- Data nullObject;
- nullObject.handle = nullptr;
- nullObject.valid = true;
- nullObject.allocated = true;
- mKnown.push_back(nullObject);
+ // Reserve ID 0 so that it can be used to represent nullptr for optional object values
+ // in the wire format. However don't tag it as allocated so that it is an error to ask
+ // KnownObjects for ID 0.
+ Data reservation;
+ reservation.handle = nullptr;
+ reservation.valid = false;
+ reservation.allocated = false;
+ mKnown.push_back(reservation);
}
// Get a backend objects for a given client ID.
