Files
secondo/Algebras/CStream/DistributeStreamServer.cpp
2026-01-23 17:03:45 +08:00

192 lines
4.8 KiB
C++

/*
----
This file is part of SECONDO.
Copyright (C) 2004, University in Hagen, Department of Computer Science,
Database Systems for New Applications.
SECONDO is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
SECONDO is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with SECONDO; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
----
//paragraph [1] Title: [{\Large \bf \begin{center}] [\end{center}}]
//characters [1] Type: [] []
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//[ae] [\"{a}]
//[oe] [\"{o}]
//[ue] [\"{u}]
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//[Oe] [\"{O}]
//[Ue] [\"{U}]
//[x] [$\times $]
//[->] [$\rightarrow $]
//[toc] [\tableofcontents]
[1] Implementation of DistributeStreamServer.
[toc]
1 DistributeStreamServer class implementation
2 Includes
*/
#include "StringUtils.h"
#include "Algebras/DBService/CommunicationUtils.hpp"
#include "DistributeStreamProtocol.h"
#include "VTHelpers.h"
#include "Algebras/Relation-C++/RelationAlgebra.h"
#include "DistributeStreamServer.h"
using namespace std;
namespace cstream {
/*
1.1 Constructor
Creates a server with a given port number and a given provided format.
If provided format is set to true the binary format is provided. If
the variable is false, the text format is provieded.
*/
DistributeStreamServer::DistributeStreamServer(
const int port, const bool providedFormat) :
Server(port), _providedFormat(providedFormat), _runner(0) {
}
/*
1.2 Destructor
Stoppes the server and all running workers.
*/
DistributeStreamServer::~DistributeStreamServer() {
if(_runner) {
_runner->interrupt();
if(listener->IsOk()) {
listener->ShutDown();
}
_runner->join();
}
boost::unique_lock<boost::mutex> lock(_workerListGuard);
for(list<DistributeStreamWorker*>::iterator it=_workerList.begin() ;
it != _workerList.end() ; ++it)
delete (*it);
}
/*
1.3 Function Definitions
1.3.1 run
Starts the server in a separate thread to wait for new client connections.
For a new communication with a client a worker thread will be started.
*/
void DistributeStreamServer::run() {
listener = Socket::CreateGlobal("localhost", stringutils::int2str(port));
_runner = new boost::thread(boost::bind(
&DistributeStreamServer::start,
this));
}
/*
1.3.2 start
This function runs in a separate thread and waits for connection requests.
If a client connect to the server the communication will be done in a
worker thread.
*/
int DistributeStreamServer::start() {
if (!listener->IsOk()) {
return 1;
}
while(true) {
try {
// wait for incoming connections and pass
// them to a new worker thread
Socket* serverConnection = listener->Accept();
if (!serverConnection || !serverConnection->IsOk()) {
if(listener)
listener->ShutDown();
return 2;
}
startCommunication(serverConnection);
}
catch (boost::thread_interrupted) {
return 0;
}
}
return 0;
}
/*
1.3.3 handleCommunicationThread
This function is used to start a new worker for a new client connection.
*/
void DistributeStreamServer::startCommunication(Socket* serverConnection) {
DistributeStreamWorker* worker =
new DistributeStreamWorker(serverConnection, _providedFormat);
if(worker->run()) {
boost::unique_lock<boost::mutex> lock(_workerListGuard);
_workerList.push_back(worker);
}
}
/*
1.3.4 pushTuple
This function pushes a given vtuple to all connected workers.
*/
void DistributeStreamServer::pushTuple(VTuple* vt) {
boost::unique_lock<boost::mutex> lock(_workerListGuard);
queue<DistributeStreamWorker*> deadWorkers;
for(list<DistributeStreamWorker*>::iterator it=_workerList.begin() ;
it != _workerList.end() ; ++it) {
if((*it)->isConnected()) {
vt->IncReference();
(*it)->pushTuple(vt);
}
else {
deadWorkers.push((*it));
}
}
// delete workers without a connection
while(!deadWorkers.empty()) {
DistributeStreamWorker* deadWorker = deadWorkers.front();
deadWorkers.pop();
_workerList.remove(deadWorker);
delete deadWorker;
}
vt->DeleteIfAllowed();
}
} /* namespace cstream */