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/*
* Copyright (c) 2020-2021, Linus Groh <linusg@serenityos.org>
* Copyright (c) 2022, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibJS/Runtime/AbstractOperations.h>
#include <LibJS/Runtime/ArrayBuffer.h>
#include <LibJS/Runtime/ArrayBufferConstructor.h>
#include <LibJS/Runtime/GlobalObject.h>
namespace JS {
ThrowCompletionOr<ArrayBuffer*> ArrayBuffer::create(GlobalObject& global_object, size_t byte_length)
{
auto buffer = ByteBuffer::create_zeroed(byte_length);
if (buffer.is_error())
return global_object.vm().throw_completion<RangeError>(global_object, ErrorType::NotEnoughMemoryToAllocate, byte_length);
return global_object.heap().allocate<ArrayBuffer>(global_object, buffer.release_value(), *global_object.array_buffer_prototype());
}
ArrayBuffer* ArrayBuffer::create(GlobalObject& global_object, ByteBuffer buffer)
{
return global_object.heap().allocate<ArrayBuffer>(global_object, move(buffer), *global_object.array_buffer_prototype());
}
ArrayBuffer* ArrayBuffer::create(GlobalObject& global_object, ByteBuffer* buffer)
{
return global_object.heap().allocate<ArrayBuffer>(global_object, buffer, *global_object.array_buffer_prototype());
}
ArrayBuffer::ArrayBuffer(ByteBuffer buffer, Object& prototype)
: Object(prototype)
, m_buffer(move(buffer))
, m_detach_key(js_undefined())
{
}
ArrayBuffer::ArrayBuffer(ByteBuffer* buffer, Object& prototype)
: Object(prototype)
, m_buffer(buffer)
, m_detach_key(js_undefined())
{
}
// 1.1.5 IsResizableArrayBuffer ( arrayBuffer ), https://tc39.es/proposal-resizablearraybuffer/#sec-isresizablearraybuffer
bool ArrayBuffer::is_resizable_array_buffer() const
{
// 1. Assert: Type(arrayBuffer) is Object and arrayBuffer has an [[ArrayBufferData]] internal slot.
// 2. If buffer has an [[ArrayBufferMaxByteLength]] internal slot, return true.
// 3. Return false.
return m_max_byte_length.has_value();
}
void ArrayBuffer::visit_edges(Cell::Visitor& visitor)
{
Base::visit_edges(visitor);
visitor.visit(m_detach_key);
}
// 25.1.2.1 AllocateArrayBuffer ( constructor, byteLength ), https://tc39.es/ecma262/#sec-allocatearraybuffer
// 1.1.2 AllocateArrayBuffer ( constructor, byteLength [, maxByteLength ] ), https://tc39.es/proposal-resizablearraybuffer/#sec-allocatearraybuffer
ThrowCompletionOr<ArrayBuffer*> allocate_array_buffer(GlobalObject& global_object, FunctionObject& constructor, size_t byte_length, Optional<size_t> max_byte_length)
{
// 1. Let slots be « [[ArrayBufferData]], [[ArrayBufferByteLength]], [[ArrayBufferDetachKey]] ».
// 2. If maxByteLength is present, append [[ArrayBufferMaxByteLength]] to slots.
// 3. Let obj be ? OrdinaryCreateFromConstructor(constructor, "%ArrayBuffer.prototype%", slots).
auto* obj = TRY(ordinary_create_from_constructor<ArrayBuffer>(global_object, constructor, &GlobalObject::array_buffer_prototype, nullptr));
// 4. Let block be ? CreateByteDataBlock(byteLength).
auto block = ByteBuffer::create_zeroed(byte_length);
if (block.is_error())
return global_object.vm().throw_completion<RangeError>(global_object, ErrorType::NotEnoughMemoryToAllocate, byte_length);
// 5. Set obj.[[ArrayBufferData]] to block.
obj->set_buffer(block.release_value());
// 6. Set obj.[[ArrayBufferByteLength]] to byteLength.
// 7. If maxByteLength is present, then
if (max_byte_length.has_value()) {
// a. Assert: byteLength ≤ maxByteLength.
VERIFY(byte_length <= *max_byte_length);
// b. If it is not possible to create a Data Block block consisting of maxByteLength bytes, throw a RangeError exception.
// c. NOTE: Resizable ArrayBuffers are designed to be implementable with in-place growth. Implementations reserve the right to throw if, for example, virtual memory cannot be reserved up front.
// d. Set obj.[[ArrayBufferMaxByteLength]] to maxByteLength.
obj->set_max_byte_length(*max_byte_length);
}
// 8. Return obj.
return obj;
}
// 25.1.2.3 DetachArrayBuffer ( arrayBuffer [ , key ] ), https://tc39.es/ecma262/#sec-detacharraybuffer
ThrowCompletionOr<Value> detach_array_buffer(GlobalObject& global_object, ArrayBuffer& array_buffer, Optional<Value> key)
{
auto& vm = global_object.vm();
// 1. Assert: IsSharedArrayBuffer(arrayBuffer) is false.
// FIXME: Check for shared buffer
// 2. If key is not present, set key to undefined.
if (!key.has_value())
key = js_undefined();
// 3. If SameValue(arrayBuffer.[[ArrayBufferDetachKey]], key) is false, throw a TypeError exception.
if (!same_value(array_buffer.detach_key(), *key))
return vm.throw_completion<TypeError>(global_object, ErrorType::DetachKeyMismatch, *key, array_buffer.detach_key());
// 4. Set arrayBuffer.[[ArrayBufferData]] to null.
// 5. Set arrayBuffer.[[ArrayBufferByteLength]] to 0.
array_buffer.detach_buffer();
// 6. Return unused.
return js_null();
}
// 25.1.2.4 CloneArrayBuffer ( srcBuffer, srcByteOffset, srcLength, cloneConstructor ), https://tc39.es/ecma262/#sec-clonearraybuffer
ThrowCompletionOr<ArrayBuffer*> clone_array_buffer(GlobalObject& global_object, ArrayBuffer& source_buffer, size_t source_byte_offset, size_t source_length)
{
// 1. Assert: IsDetachedBuffer(srcBuffer) is false.
VERIFY(!source_buffer.is_detached());
// 2. Let targetBuffer be ? AllocateArrayBuffer(%ArrayBuffer%, srcLength).
auto* target_buffer = TRY(allocate_array_buffer(global_object, *global_object.array_buffer_constructor(), source_length));
// 3. Let srcBlock be srcBuffer.[[ArrayBufferData]].
auto& source_block = source_buffer.buffer();
// 4. Let targetBlock be targetBuffer.[[ArrayBufferData]].
auto& target_block = target_buffer->buffer();
// 5. Perform CopyDataBlockBytes(targetBlock, 0, srcBlock, srcByteOffset, srcLength).
// FIXME: This is only correct for ArrayBuffers, once SharedArrayBuffer is implemented, the AO has to be implemented
target_block.overwrite(0, source_block.offset_pointer(source_byte_offset), source_length);
// 6. Return targetBuffer.
return target_buffer;
}
}
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