overte-lubosz/assignment-client/src/AssignmentClientMonitor.cpp
2014-12-11 10:21:11 -08:00

98 lines
3.4 KiB
C++

//
// AssignmentClientMonitor.cpp
// assignment-client/src
//
// Created by Stephen Birarda on 1/10/2014.
// Copyright 2014 High Fidelity, Inc.
//
// Distributed under the Apache License, Version 2.0.
// See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
//
#include <signal.h>
#include <LogHandler.h>
#include <ShutdownEventListener.h>
#include "AssignmentClientMonitor.h"
const char* NUM_FORKS_PARAMETER = "-n";
const QString ASSIGNMENT_CLIENT_MONITOR_TARGET_NAME = "assignment-client-monitor";
AssignmentClientMonitor::AssignmentClientMonitor(int &argc, char **argv, int numAssignmentClientForks) :
QCoreApplication(argc, argv)
{
// start the Logging class with the parent's target name
LogHandler::getInstance().setTargetName(ASSIGNMENT_CLIENT_MONITOR_TARGET_NAME);
// setup a shutdown event listener to handle SIGTERM or WM_CLOSE for us
#ifdef _WIN32
installNativeEventFilter(&ShutdownEventListener::getInstance());
#else
ShutdownEventListener::getInstance();
#endif
_childArguments = arguments();
// remove the parameter for the number of forks so it isn't passed to the child forked processes
int forksParameterIndex = _childArguments.indexOf(NUM_FORKS_PARAMETER);
// this removes both the "-n" parameter and the number of forks passed
_childArguments.removeAt(forksParameterIndex);
_childArguments.removeAt(forksParameterIndex);
// use QProcess to fork off a process for each of the child assignment clients
for (int i = 0; i < numAssignmentClientForks; i++) {
spawnChildClient();
}
}
AssignmentClientMonitor::~AssignmentClientMonitor() {
stopChildProcesses();
}
void AssignmentClientMonitor::stopChildProcesses() {
QList<QPointer<QProcess> >::Iterator it = _childProcesses.begin();
while (it != _childProcesses.end()) {
if (!it->isNull()) {
qDebug() << "Monitor is terminating child process" << it->data();
// don't re-spawn this child when it goes down
disconnect(it->data(), 0, this, 0);
it->data()->terminate();
it->data()->waitForFinished();
}
it = _childProcesses.erase(it);
}
}
void AssignmentClientMonitor::spawnChildClient() {
QProcess *assignmentClient = new QProcess(this);
_childProcesses.append(QPointer<QProcess>(assignmentClient));
// make sure that the output from the child process appears in our output
assignmentClient->setProcessChannelMode(QProcess::ForwardedChannels);
assignmentClient->start(applicationFilePath(), _childArguments);
// link the child processes' finished slot to our childProcessFinished slot
connect(assignmentClient, SIGNAL(finished(int, QProcess::ExitStatus)), this,
SLOT(childProcessFinished(int, QProcess::ExitStatus)));
qDebug() << "Spawned a child client with PID" << assignmentClient->pid();
}
void AssignmentClientMonitor::childProcessFinished(int exitCode, QProcess::ExitStatus exitStatus) {
qDebug("Replacing dead child assignment client with a new one");
// remove the old process from our list of child processes
qDebug() << "need to remove" << QPointer<QProcess>(qobject_cast<QProcess*>(sender()));
_childProcesses.removeOne(QPointer<QProcess>(qobject_cast<QProcess*>(sender())));
spawnChildClient();
}