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/*
* Copyright (c) 2021, Idan Horowitz <idan.horowitz@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibJS/Runtime/AbstractOperations.h>
#include <LibJS/Runtime/FinalizationRegistry.h>
namespace JS {
FinalizationRegistry::FinalizationRegistry(Realm& realm, JS::JobCallback cleanup_callback, Object& prototype)
: Object(prototype)
, WeakContainer(heap())
, m_realm(JS::make_handle(realm))
, m_cleanup_callback(move(cleanup_callback))
{
}
FinalizationRegistry::~FinalizationRegistry()
{
}
void FinalizationRegistry::add_finalization_record(Cell& target, Value held_value, Object* unregister_token)
{
VERIFY(!held_value.is_empty());
m_records.append({ &target, held_value, unregister_token });
}
bool FinalizationRegistry::remove_by_token(Object& unregister_token)
{
auto removed = false;
for (auto it = m_records.begin(); it != m_records.end(); ++it) {
if (it->unregister_token == &unregister_token) {
it.remove(m_records);
removed = true;
}
}
return removed;
}
void FinalizationRegistry::remove_dead_cells(Badge<Heap>)
{
auto any_cells_were_removed = false;
for (auto& record : m_records) {
if (!record.target || record.target->state() == Cell::State::Live)
continue;
record.target = nullptr;
any_cells_were_removed = true;
break;
}
if (any_cells_were_removed)
vm().host_enqueue_finalization_registry_cleanup_job(*this);
}
// 9.13 CleanupFinalizationRegistry ( finalizationRegistry ), https://tc39.es/ecma262/#sec-cleanup-finalization-registry
ThrowCompletionOr<void> FinalizationRegistry::cleanup(Optional<JobCallback> callback)
{
auto& vm = this->vm();
auto& global_object = this->global_object();
// 1. Assert: finalizationRegistry has [[Cells]] and [[CleanupCallback]] internal slots.
// Note: Ensured by type.
// 2. Let callback be finalizationRegistry.[[CleanupCallback]].
auto& cleanup_callback = callback.has_value() ? callback.value() : m_cleanup_callback;
// 3. While finalizationRegistry.[[Cells]] contains a Record cell such that cell.[[WeakRefTarget]] is empty, an implementation may perform the following steps:
for (auto it = m_records.begin(); it != m_records.end(); ++it) {
// a. Choose any such cell.
if (it->target != nullptr)
continue;
// b. Remove cell from finalizationRegistry.[[Cells]].
MarkedVector<Value> arguments(vm.heap());
arguments.append(it->held_value);
it.remove(m_records);
// c. Perform ? HostCallJobCallback(callback, undefined, « cell.[[HeldValue]] »).
TRY(vm.host_call_job_callback(global_object, cleanup_callback, js_undefined(), move(arguments)));
}
// 4. Return NormalCompletion(empty).
return {};
}
void FinalizationRegistry::visit_edges(Cell::Visitor& visitor)
{
Base::visit_edges(visitor);
for (auto& record : m_records) {
visitor.visit(record.held_value);
visitor.visit(record.unregister_token);
}
}
}
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