From 2aa4a82499d4becd2284cdb482213d541b8804dd Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 28 Apr 2024 16:29:10 +0200 Subject: Adding upstream version 86.0.1. Signed-off-by: Daniel Baumann --- dom/bindings/RootedOwningNonNull.h | 58 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 58 insertions(+) create mode 100644 dom/bindings/RootedOwningNonNull.h (limited to 'dom/bindings/RootedOwningNonNull.h') diff --git a/dom/bindings/RootedOwningNonNull.h b/dom/bindings/RootedOwningNonNull.h new file mode 100644 index 0000000000..cbcb5c4ecd --- /dev/null +++ b/dom/bindings/RootedOwningNonNull.h @@ -0,0 +1,58 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this file, + * You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/** + * An implementation of Rooted for OwningNonNull. This works by assuming + * that T has a Trace() method defined on it which will trace whatever things + * inside the T instance need tracing. + * + * This implementation has one serious drawback: operator= doesn't work right + * because it's declared on Rooted directly and expects the type Rooted is + * templated over. + */ + +#ifndef mozilla_RootedOwningNonNull_h__ +#define mozilla_RootedOwningNonNull_h__ + +#include "mozilla/OwningNonNull.h" +#include "js/GCPolicyAPI.h" +#include "js/TypeDecls.h" + +namespace JS { +template +struct GCPolicy> { + typedef mozilla::OwningNonNull SmartPtrType; + + static SmartPtrType initial() { return SmartPtrType(); } + + static void trace(JSTracer* trc, SmartPtrType* tp, const char* name) { + // We have to be very careful here. Normally, OwningNonNull can't be null. + // But binding code can end up in a situation where it sets up a + // Rooted and then before it gets a chance to assign to it + // (e.g. from the constructor of the thing being assigned) a GC happens. So + // we can land here when *tp stores a null pointer because it's not + // initialized. + // + // So we need to check for that before jumping. + if ((*tp).isInitialized()) { + (*tp)->Trace(trc); + } + } + + static bool isValid(const SmartPtrType& v) { + return !v.isInitialized() || GCPolicy::isValid(v); + } +}; +} // namespace JS + +namespace js { +template +struct WrappedPtrOperations, Wrapper> { + operator T&() const { return static_cast(this)->get(); } +}; +} // namespace js + +#endif /* mozilla_RootedOwningNonNull_h__ */ -- cgit v1.2.3