Qt , QMutex: destroying locked mutex then app crash - qt

Question

I make an http operation(get,post etc...) by using QNetworkAccessManager. I run a few "get" operation in paralel. For this , I use QtConcurrent::run(this,&RestWebservice::GetHTTPData) to make multi HTTP operations.
My problem is When I close the app before HTTP operation does not complete , App is crashed.Application Output write this line QMutex: destroying locked mutex then write The program has unexpectedly finished.
I guest problem occurs in this line
void RestWebservice::get()
{
// mutex.lock();
m_networkManager.get(m_networkrequest);
// mutex.unlock();
}
But I am not sure because QtCreater Debugger is not good like VS.By the way , GetHTTPData is in different class.
MY CODE for start network Operation:(MobileOperation.cpp).For exapmle getUserAccount metod start a http operation.
void MobileOperations::getWorkOrderListT(int ekipId) {
MyGlobal::Metods metod=MyGlobal::EkipIsEmriListesi;
QString parameters="{EkipId}";
QMap<QString,QVariant> paramlist;
paramlist["EkipId"]=ekipId;
GetHTTPData(metod,parameters,paramlist);
if(m_workorder.IsSuccess==true)
{
// emit successupdatewo();
if(m_workorder.workorders.count()>0)
{
InsertWo(json.workorder->workorders);
emit processstop("İş Emri Listesi Güncellendi");
// QThread::sleep(2);
}
else
{
emit processstop(json.workorder->ReturnMessage);
}
emit successworkstart();
}
else
{
emit processstop("Bağlantı Başarısız Oldu");
}
}
void MobileOperations::getUserAccount(QString kullaniciAdi, QString sifre,bool isremember)
{
json.user=m_user;
QtConcurrent::run(this,&MobileOperations::getUserAccountT,kullaniciAdi,sifre,isremember);
// getUserAccountT(kullaniciAdi,sifre,isremember);
processstart("Baglaniyor");
}
void MobileOperations::GetHTTPData(MyGlobal::Metods MetodName, QString Parameters, QMap<QString, QVariant> paramlist)
{
try
{
parameter=new HttpRequest();
parameter->url=m_url;
parameter->metodname=MetodName;
parameter->resource=m_path;
parameter->appid=m_appid;
parameter->apppass=m_apppass;
parameter->parametersname=Parameters;
parameter->params=paramlist;
rest= new RestWebservice(parameter->GenerateHTTPQuery(),MetodName);
// json=new JSonParser();
// loop=new QEventLoop();
loop=new QEventLoop();
QObject::connect(rest,SIGNAL(sendhttpdata(QByteArray,MyGlobal::Metods)),&json,SLOT(onGetData(QByteArray,MyGlobal::Metods)));
QObject::connect(&json,SIGNAL(serilazitionCompleted()),loop,SLOT(quit()));
rest->get();
loop->exec();
}
catch(std::string &exp)
{
qDebug()<<"Sonlandırıldı";
}
}
MY CODE of classes For HTTP operatins :
#include "restwebservice.h"
#include <QJsonDocument>
#include<QJsonArray>
#include <QJsonObject>
#include<QJsonValue>
#include<QList>
#include <QThread>
RestWebservice::RestWebservice(QNetworkRequest request,
MyGlobal::Metods metod,
QObject* parent):QObject(parent),m_networkrequest(request),m_metodname(metod)
{
connect(&m_networkManager, SIGNAL(finished(QNetworkReply*)),this, SLOT(onResult(QNetworkReply*)));
// connect(&m_networkManager,SIGNAL())
}
void RestWebservice::get()
{
// mutex.lock();
m_networkManager.get(m_networkrequest);
// mutex.unlock();
}
void RestWebservice::post(QString request)
{
QByteArray requestA= request.toUtf8();
m_networkManager.post(m_networkrequest,requestA);
}
void RestWebservice::onResult(QNetworkReply* reply)
{
try
{
if (reply->error() != QNetworkReply::NoError)
{
qDebug()<<reply->error()<<":"<<reply->errorString();
MyGlobal::NetworkStatus=reply->errorString();
emit sendhttpdata(m_data,m_metodname);
return;
// throw(reply->errorString().toStdString());
}
QByteArray data = reply->readAll();
reply->deleteLater();
m_data=data;
MyGlobal::NetworkStatus="Tablolar Yüklendi";
emit sendhttpdata(m_data,m_metodname);
}
catch(std::string exp)
{
qDebug()<<"Exception:"<<QString::fromStdString(exp);
}
catch(std::exception &exp)
{
qDebug()<<"Exception:"<<QString::fromStdString(exp.what());
}
}
void RestWebservice::onError()
{
qDebug()<<"Hata VAR";
}
HttpRequest::HttpRequest(QObject *parent) :
QObject(parent)
{
}
QNetworkRequest HttpRequest::GenerateHTTPQuery()
{
// QString path="";
QString path=QString("/%1/%2/%3/%4/%5").arg(resource).arg(MyGlobal::getMetodName(metodname)).arg(appid).arg(apppass).arg(parametersname);
foreach (QString param, params.keys()) {
path.replace("{"+param+"}",params[param].toString());
}
QUrl m_url(url);
m_url.setPath(path);
m_request.setUrl(m_url);
m_request.setRawHeader("Content-Type","application/json;charset=utf-8");
// m_request.setRawHeader("SOAPAction","http://tempuri.org/IMobileClient/UserAuth");
qDebug()<<m_url.url();
return m_request;
}
QNetworkRequest HttpRequest::GenerateHTTPQueryPost()
{
// QString path="";
QString path=QString("/%1/%2").arg(resource).arg(MyGlobal::getMetodName(metodname));
QUrl m_url(url);
m_url.setPath(path);
m_request.setUrl(m_url);
m_request.setRawHeader("Content-Type","application/json;charset=utf-8");
// m_request.setRawHeader("SOAPAction","http://tempuri.org/IMobileClient/UserAuth");
qDebug()<<m_url.url();
return m_request;
}

Answer 1

Is you mutex a member of your class. In that case the mutex is destructed before it is unlocked (as I presume the containing class goes out of scope), which causes the message you see. The destructor of the mutex is called when the class is destructed, while the lock is held. This is a problem. Typically you will have to find a way to not block indefinitely during your network request.