forked from mirrors/gecko-dev
69 lines
2.5 KiB
C++
69 lines
2.5 KiB
C++
/* -*- 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/. */
|
|
|
|
#ifndef mozilla_dom_UniFFIPointer_h
|
|
#define mozilla_dom_UniFFIPointer_h
|
|
|
|
#include "nsISupports.h"
|
|
#include "nsWrapperCache.h"
|
|
#include "nsString.h"
|
|
#include "mozilla/ErrorResult.h"
|
|
#include "mozilla/dom/TypedArray.h"
|
|
#include "mozilla/dom/UniFFIPointerType.h"
|
|
|
|
namespace mozilla::dom {
|
|
|
|
class UniFFIPointer final : public nsISupports, public nsWrapperCache {
|
|
public:
|
|
NS_DECL_CYCLE_COLLECTING_ISUPPORTS
|
|
NS_DECL_CYCLE_COLLECTION_WRAPPERCACHE_CLASS(UniFFIPointer)
|
|
|
|
static already_AddRefed<UniFFIPointer> Create(
|
|
void* aPtr, const uniffi::UniFFIPointerType* aType);
|
|
static already_AddRefed<UniFFIPointer> Read(
|
|
const ArrayBuffer& aArrayBuff, uint32_t aPosition,
|
|
const uniffi::UniFFIPointerType* aType, ErrorResult& aError);
|
|
void Write(const ArrayBuffer& aArrayBuff, uint32_t aPosition,
|
|
const uniffi::UniFFIPointerType* aType, ErrorResult& aError) const;
|
|
|
|
UniFFIPointer(void* aPtr, const uniffi::UniFFIPointerType* aType);
|
|
|
|
JSObject* WrapObject(JSContext* aCx,
|
|
JS::Handle<JSObject*> aGivenProto) override;
|
|
nsISupports* GetParentObject() { return nullptr; }
|
|
|
|
/**
|
|
* returns the raw pointer `UniFFIPointer` holds
|
|
* This is safe because:
|
|
* - The pointer was allocated in Rust as a reference counted `Arc<T>`
|
|
* - Rust cloned the pointer without destructing it when passed into C++
|
|
* - Eventually, when the destructor of `UniFFIPointer` runs, we return
|
|
* ownership to Rust, which then decrements the count and deallocates the
|
|
* memory the pointer points to.
|
|
*/
|
|
void* GetPtr() const;
|
|
|
|
/**
|
|
* Returns true if the pointer type `this` holds is the same as the argument
|
|
* it does so using pointer comparison, as there is **exactly** one static
|
|
* `UniFFIPointerType` per type exposed in the UniFFI interface
|
|
*/
|
|
bool IsSamePtrType(const uniffi::UniFFIPointerType* type) const;
|
|
|
|
private:
|
|
const uniffi::UniFFIPointerType* mType;
|
|
void* mPtr;
|
|
|
|
protected:
|
|
/**
|
|
* Destructs the `UniFFIPointer`, making sure to give back ownership of the
|
|
* raw pointer back to Rust, which deallocates the pointer
|
|
*/
|
|
~UniFFIPointer();
|
|
};
|
|
} // namespace mozilla::dom
|
|
|
|
#endif /* mozilla_dom_UniFFIPointer_h */
|