Files
sdk/runtime/vm/native_message_handler.h
T
Vyacheslav Egorov bf36861cb3 [vm] Fix race in NativeMessageHandler
Introduce `NativeMessageHandler::Cleanup` which
waits for all pending `NativeMessageHandler`
deletions to complete.

Fixes https://github.com/dart-lang/sdk/issues/56744

TEST=hard to distill this specific race into a test

Change-Id: Id6196f955ff7a874c07d3a11f766d74accbde96c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/385780
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Commit-Queue: Slava Egorov <vegorov@google.com>
2024-09-18 21:07:59 +00:00

81 lines
2.5 KiB
C++

// Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
#ifndef RUNTIME_VM_NATIVE_MESSAGE_HANDLER_H_
#define RUNTIME_VM_NATIVE_MESSAGE_HANDLER_H_
#include <memory>
#include "include/dart_api.h"
#include "include/dart_native_api.h"
#include "vm/message_handler.h"
namespace dart {
// A NativeMessageHandler accepts messages and dispatches them to
// native C handlers on worker threads. It will spawn up to
// |max_concurrency| worker threads which will handle incomming messages
// concurrently.
class NativeMessageHandler final : public PortHandler {
public:
NativeMessageHandler(const char* name,
Dart_NativeMessageHandler func,
intptr_t max_concurrency);
~NativeMessageHandler() override;
const char* name() const override { return name_.get(); }
Dart_NativeMessageHandler func() const { return func_; }
#if defined(DEBUG)
// Check that it is safe to access this handler.
void CheckAccess() const override;
#endif
void OnPortClosed(Dart_Port port) override {}
Isolate* isolate() const override { return nullptr; }
// Posts a message on this handler's message queue.
// If before_events is true, then the message is enqueued before any pending
// events, but after any pending isolate library events.
void PostMessage(std::unique_ptr<Message> message,
bool before_events = false) override;
// Request deletion of the given handler once it is down with the currently
// running Dart_NativeMessageHandler callbacks. No new callbacks will be
// scheduled after this call.
//
// |handler| might be deleted synchronously if no callback is running,
// or it can be deleted later on a worker thread.
//
// |RequestDeletion| should be called after |Init| but before |Cleanup|.
// |Cleanup| will wait for all pending deletions to complete - which allows
// VM to shutdown cleanly.
static void RequestDeletion(NativeMessageHandler* handler);
void Shutdown() override;
static void Init();
static void Cleanup();
private:
PortSet<PortSetEntry>* ports(PortMap::Locker& locker) override {
return nullptr;
}
static Monitor* monitor_;
static intptr_t pending_deletions_;
CStringUniquePtr name_;
const Dart_NativeMessageHandler func_;
ThreadPool pool_;
};
} // namespace dart
#endif // RUNTIME_VM_NATIVE_MESSAGE_HANDLER_H_