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/* -*- 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/. */
#include "mozilla/Assertions.h" // MOZ_ASSERT
#include <stdint.h> // uint8_t, uint32_t
#include "jstypes.h" // JS_PUBLIC_API
#include "js/ArrayBufferMaybeShared.h"
#include "vm/ArrayBufferObject.h" // js::ArrayBufferObject
#include "vm/JSObject.h" // JSObject
#include "vm/SharedArrayObject.h" // js::SharedArrayBufferObject
#include "vm/SharedMem.h" // SharedMem
using namespace js;
JS_PUBLIC_API bool JS::IsArrayBufferObjectMaybeShared(JSObject* obj) {
return obj->canUnwrapAs<ArrayBufferObjectMaybeShared>();
}
JS_PUBLIC_API JSObject* JS::UnwrapArrayBufferMaybeShared(JSObject* obj) {
return obj->maybeUnwrapIf<ArrayBufferObjectMaybeShared>();
}
JS_PUBLIC_API void JS::GetArrayBufferMaybeSharedLengthAndData(
JSObject* obj, size_t* length, bool* isSharedMemory, uint8_t** data) {
MOZ_ASSERT(obj->is<ArrayBufferObjectMaybeShared>());
if (obj->is<SharedArrayBufferObject>()) {
auto* buffer = &obj->as<SharedArrayBufferObject>();
*length = buffer->byteLength().get();
*data = buffer->dataPointerShared().unwrap();
*isSharedMemory = true;
} else {
auto* buffer = &obj->as<ArrayBufferObject>();
*length = buffer->byteLength().get();
*data = buffer->dataPointer();
*isSharedMemory = false;
}
}
JS_PUBLIC_API uint8_t* JS::GetArrayBufferMaybeSharedData(
JSObject* obj, bool* isSharedMemory, const JS::AutoRequireNoGC&) {
MOZ_ASSERT(obj->maybeUnwrapIf<ArrayBufferObjectMaybeShared>());
if (ArrayBufferObject* aobj = obj->maybeUnwrapIf<ArrayBufferObject>()) {
*isSharedMemory = false;
return aobj->dataPointer();
} else if (SharedArrayBufferObject* saobj =
obj->maybeUnwrapIf<SharedArrayBufferObject>()) {
*isSharedMemory = true;
return saobj->dataPointerShared().unwrap();
}
return nullptr;
}
JS_PUBLIC_API bool JS::IsLargeArrayBufferMaybeShared(JSObject* obj) {
#ifdef JS_64BIT
obj = UnwrapArrayBufferMaybeShared(obj);
MOZ_ASSERT(obj);
size_t len = obj->is<ArrayBufferObject>()
? obj->as<ArrayBufferObject>().byteLength().get()
: obj->as<SharedArrayBufferObject>().byteLength().get();
return len > ArrayBufferObject::MaxByteLengthForSmallBuffer;
#else
// Large ArrayBuffers are not supported on 32-bit.
MOZ_ASSERT(ArrayBufferObject::maxBufferByteLength() ==
ArrayBufferObject::MaxByteLengthForSmallBuffer);
return false;
#endif
}