[Unity][UE] websocketpp封装对象gc时可能anr

[chexiongsheng]

detail | 详细描述

线上业务概率出现，我自己复现不出来，先记录下

/apex/com.android.runtime/lib64/bionic/libc.so (syscall+32) [arm64-v8a]
/apex/com.android.runtime/lib64/bionic/libc.so (pthread_join+244) [arm64-v8a]
puerts_asio::detail::posix_thread::join()
puerts/unity/native_src/../../unreal/Puerts/ThirdParty/Include/asio/asio/detail/impl/posix_thread.ipp:41
puerts_asio::detail::resolver_service_base::base_shutdown()
puerts/unity/native_src/../../unreal/Puerts/ThirdParty/Include/asio/asio/detail/impl/resolver_service_base.ipp:65
puerts_asio::detail::service_registry::shutdown_services()
puerts/unity/native_src/../../unreal/Puerts/ThirdParty/Include/asio/asio/detail/impl/service_registry.ipp:43
puerts_asio::execution_context::shutdown()
puerts/unity/native_src/../../unreal/Puerts/ThirdParty/Include/asio/asio/impl/execution_context.ipp:40
puerts_asio::execution_context::~execution_context()
puerts/unity/native_src/../../unreal/Puerts/ThirdParty/Include/asio/asio/impl/execution_context.ipp:33
websocketpp::transport::puerts_asio::endpoint<websocketpp::config::asio_tls::transport_config>::~endpoint()
/data/landun/workspace/puerts/unity/native_src/../../unreal/Puerts/ThirdParty/Include/websocketpp/websocketpp/transport/asio/endpoint.hpp:113
puerts::V8WebSocketClientImpl::~V8WebSocketClientImpl()
puerts/unreal/Puerts/Source/JsEnv/Private/WebSocketImpl.cpp:78

[chexiongsheng]

业务通过这种方式规避

void OnGarbageCollectedWithFree(const v8::WeakCallbackInfo<V8WebSocketClientImpl>& Data)
{
    auto client = Data.GetParameter();
    client->CloseImmediately(websocketpp::close::status::normal, "");

    // delete client step1
    client->GContext.Reset();
    client->GSelf.Reset();
    for (auto i = 0; i < V8WebSocketClientImpl::HANDLE_TYPE_END; ++i)
    {
        client->Handles[i].Reset();
    }
    // delete client step2
    std::thread([=] {delete client;}).detach();
}

[chexiongsheng]

看栈应该是dns解析，这在很多系统下都是只能一直阻塞不能中断的。
上述规避是个能解决问题的小改动，缺点是开销有点大。
可以改进下，改为放到一个线程队列里头去析构。