mirror of
https://github.com/OpenNebula/one.git
synced 2024-12-23 17:33:56 +03:00
112 lines
2.9 KiB
C++
112 lines
2.9 KiB
C++
/* -------------------------------------------------------------------------- */
|
|
/* Copyright 2002-2023, OpenNebula Project, OpenNebula Systems */
|
|
/* */
|
|
/* Licensed under the Apache License, Version 2.0 (the "License"); you may */
|
|
/* not use this file except in compliance with the License. You may obtain */
|
|
/* a copy of the License at */
|
|
/* */
|
|
/* http://www.apache.org/licenses/LICENSE-2.0 */
|
|
/* */
|
|
/* Unless required by applicable law or agreed to in writing, software */
|
|
/* distributed under the License is distributed on an "AS IS" BASIS, */
|
|
/* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. */
|
|
/* See the License for the specific language governing permissions and */
|
|
/* limitations under the License. */
|
|
/* -------------------------------------------------------------------------- */
|
|
|
|
#ifndef REQUEST_MANAGER_CONNECTION_H_
|
|
#define REQUEST_MANAGER_CONNECTION_H_
|
|
|
|
#include "RequestManager.h"
|
|
#include <condition_variable>
|
|
|
|
/**
|
|
* The connection manager class synchronizes the connection and manager threads
|
|
*/
|
|
class ConnectionManager
|
|
{
|
|
public:
|
|
ConnectionManager(int mc)
|
|
: connections(0)
|
|
, max_connections(mc)
|
|
, end(false)
|
|
{
|
|
}
|
|
|
|
~ConnectionManager() = default;
|
|
|
|
/**
|
|
* Increments number of active connections
|
|
*/
|
|
int add()
|
|
{
|
|
std::lock_guard<std::mutex> lock(_mutex);
|
|
|
|
return ++connections;
|
|
}
|
|
|
|
/**
|
|
* Decrements number of active connections and signals management thread
|
|
*/
|
|
void del()
|
|
{
|
|
std::lock_guard<std::mutex> lock(_mutex);
|
|
|
|
--connections;
|
|
|
|
cond.notify_one();
|
|
}
|
|
|
|
/**
|
|
* Waits for active connections to be under the max_connection threshold
|
|
*/
|
|
void wait()
|
|
{
|
|
std::unique_lock<std::mutex> lock(_mutex);
|
|
|
|
if (end)
|
|
{
|
|
return;
|
|
}
|
|
|
|
cond.wait(lock, [&]{
|
|
return (connections < max_connections) || end; });
|
|
}
|
|
|
|
/**
|
|
* Interrupts and prevents wait() operations
|
|
*/
|
|
void terminate()
|
|
{
|
|
std::lock_guard<std::mutex> lock(_mutex);
|
|
|
|
end = true;
|
|
|
|
cond.notify_one();
|
|
}
|
|
|
|
private:
|
|
/**
|
|
* Synchronization for connection threads and listener thread
|
|
*/
|
|
std::mutex _mutex;
|
|
std::condition_variable cond;
|
|
|
|
/**
|
|
* Number of active connections
|
|
*/
|
|
int connections;
|
|
|
|
/**
|
|
* Max number of active connections
|
|
*/
|
|
int max_connections;
|
|
|
|
/**
|
|
* Terminate wait
|
|
*/
|
|
std::atomic<bool> end;
|
|
};
|
|
|
|
#endif
|