Function GetNamingServiceThread

src/brpc/details/naming_service_thread.cpp:415–490

}

int GetNamingServiceThread(
    butil::intrusive_ptr<NamingServiceThread>* nsthread_out,
    const char* url,
    const GetNamingServiceThreadOptions* options) {
    char protocol[MAX_PROTOCOL_LEN + 1];
    const char* const service_name = ParseNamingServiceUrl(url, protocol);
    if (service_name == NULL) {
        LOG(ERROR) << "Invalid naming service url=" << url;
        return -1;
    }
    const NamingService* source_ns = NamingServiceExtension()->Find(protocol);
    if (source_ns == NULL) {
        LOG(ERROR) << "Unknown protocol=" << protocol;
        return -1;
    }
    const NSKey key(protocol, service_name,
                    (options ? options->channel_signature : ChannelSignature()));
    bool new_thread = false;
    butil::intrusive_ptr<NamingServiceThread> nsthread;
    {
        std::unique_lock<pthread_mutex_t> mu(g_nsthread_map_mutex);
        if (g_nsthread_map == NULL) {
            g_nsthread_map = new (std::nothrow) NamingServiceMap;
            if (NULL == g_nsthread_map) {
                mu.unlock();
                LOG(ERROR) << "Fail to new g_nsthread_map";
                return -1;
            }
            if (g_nsthread_map->init(64) != 0) {
                LOG(WARNING) << "Fail to init g_nsthread_map";
            }
        }
        NamingServiceThread*& ptr = (*g_nsthread_map)[key];
        if (ptr != NULL) {
            if (ptr->AddRefManually() == 0) {
                // The ns thread's last intrusive_ptr was just destructed and
                // the removal-from-global-map-code in ptr->~NamingServiceThread()
                // is about to run or already running, need to create another ns
                // thread.
                // Notice that we don't need to remove the reference because
                // the object is already destructing.
                ptr = NULL;
            } else {
                nsthread.reset(ptr, false);
            }
        }
        if (ptr == NULL) {
            NamingServiceThread* thr = new (std::nothrow) NamingServiceThread;
            if (thr == NULL) {
                mu.unlock();
                LOG(ERROR) << "Fail to new NamingServiceThread";
                return -1;
            }
            ptr = thr;
            nsthread.reset(ptr);
            new_thread = true;
        }
    }