blob: 5c355abe9bbc6a262a369430cd625d6e94bbd8de [file] [log] [blame]
// Copyright 2013 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <memory>
#include "flutter/fml/macros.h"
#include "flutter/lib/ui/isolate_name_server/isolate_name_server.h"
#include "flutter/runtime/dart_vm.h"
#include "flutter/runtime/service_protocol.h"
namespace flutter {
// A strong reference to the Dart VM. There can only be one VM running in the
// process at any given time. A reference to the VM may only be obtained via the
// |Create| method. In case there is already a running instance of the VM in the
// process, a strong reference to that VM is obtained and the arguments to the
// |Create| call ignored. If there is no VM already running in the process, a VM
// is initialized in a thread safe manner and returned to the caller. The VM
// will shutdown only when all callers relinquish their references (by
// collecting their instances of this class).
// DartVMRef instances may be created on any thread.
class DartVMRef {
[[nodiscard]] static DartVMRef Create(
Settings settings,
fml::RefPtr<DartSnapshot> vm_snapshot = nullptr,
fml::RefPtr<DartSnapshot> isolate_snapshot = nullptr);
// This is an inherently racy way to check if a VM instance is running and
// should not be used outside of unit-tests where there is a known threading
// model.
static bool IsInstanceRunning();
static std::shared_ptr<const DartVMData> GetVMData();
static std::shared_ptr<ServiceProtocol> GetServiceProtocol();
static std::shared_ptr<IsolateNameServer> GetIsolateNameServer();
operator bool() const { return static_cast<bool>(vm_); }
DartVM* get() {
return vm_.get();
DartVM* operator->() {
return vm_.get();
DartVM* operator&() {
return vm_.get();
friend class DartIsolate;
std::shared_ptr<DartVM> vm_;
DartVMRef(std::shared_ptr<DartVM> vm);
// Only used by Dart Isolate to register itself with the VM.
static DartVM* GetRunningVM();
} // namespace flutter