From 26a029d407be480d791972afb5975cf62c9360a6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Fri, 19 Apr 2024 02:47:55 +0200 Subject: Adding upstream version 124.0.1. Signed-off-by: Daniel Baumann --- js/public/friend/DOMProxy.h | 91 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 91 insertions(+) create mode 100644 js/public/friend/DOMProxy.h (limited to 'js/public/friend/DOMProxy.h') diff --git a/js/public/friend/DOMProxy.h b/js/public/friend/DOMProxy.h new file mode 100644 index 0000000000..533c327adb --- /dev/null +++ b/js/public/friend/DOMProxy.h @@ -0,0 +1,91 @@ +/* -*- 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/. */ + +/* + * Specify information about DOMProxy proxies in the DOM, for use by ICs. + * + * Embedders who don't need to define particularly high-performance proxies that + * can have random properties added to them can ignore this header. + */ + +#ifndef js_friend_DOMProxy_h +#define js_friend_DOMProxy_h + +#include // size_t +#include // uint64_t + +#include "jstypes.h" // JS_PUBLIC_API + +#include "js/Id.h" // JS::PropertyKey +#include "js/RootingAPI.h" // JS::Handle, JS::Heap +#include "js/Value.h" // JS::UndefinedValue, JS::Value + +struct JS_PUBLIC_API JSContext; +class JS_PUBLIC_API JSObject; + +namespace JS { + +/* + * The DOMProxyShadowsCheck function will be called to check if the property for + * id should be gotten from the prototype, or if there is an own property that + * shadows it. + * * If ShadowsViaDirectExpando is returned, then the slot at + * listBaseExpandoSlot contains an expando object which has the property in + * question. + * * If ShadowsViaIndirectExpando is returned, then the slot at + * listBaseExpandoSlot contains a private pointer to an ExpandoAndGeneration + * and the expando object in the ExpandoAndGeneration has the property in + * question. + * * If DoesntShadow is returned then the slot at listBaseExpandoSlot should + * either be undefined or point to an expando object that would contain the + * own property. + * * If DoesntShadowUnique is returned then the slot at listBaseExpandoSlot + * should contain a private pointer to a ExpandoAndGeneration, which contains + * a JS::Value that should either be undefined or point to an expando object, + * and a uint64 value. If that value changes then the IC for getting a + * property will be invalidated. + * * If Shadows is returned, that means the property is an own property of the + * proxy but doesn't live on the expando object. + */ + +struct ExpandoAndGeneration { + ExpandoAndGeneration() : expando(JS::UndefinedValue()), generation(0) {} + + void OwnerUnlinked() { ++generation; } + + static constexpr size_t offsetOfExpando() { + return offsetof(ExpandoAndGeneration, expando); + } + + static constexpr size_t offsetOfGeneration() { + return offsetof(ExpandoAndGeneration, generation); + } + + Heap expando; + uint64_t generation; +}; + +enum class DOMProxyShadowsResult { + ShadowCheckFailed, + Shadows, + DoesntShadow, + DoesntShadowUnique, + ShadowsViaDirectExpando, + ShadowsViaIndirectExpando +}; + +using DOMProxyShadowsCheck = DOMProxyShadowsResult (*)(JSContext*, + Handle, + Handle); + +extern JS_PUBLIC_API void SetDOMProxyInformation( + const void* domProxyHandlerFamily, + DOMProxyShadowsCheck domProxyShadowsCheck, + const void* domRemoteProxyHandlerFamily); + +} // namespace JS + +#endif // js_friend_DOMProxy_h -- cgit v1.2.3