Create lock file in config folder instead of temp folder

Some linux distros seem to alter TMPDIR environment variable and
therefore hamper qbt ability to find the lock files. So use config
folder instead of TMPDIR folder to create/locate the lock files.
Note that this change will also make qbt become one instance per-user
instead of one instance per-system.

Closes #15646.

src/app/application.cpp

@@ -154,17 +154,11 @@ Application::Application(int &argc, char **argv)
     const QString profileDir = portableModeEnabled
         ? QDir(QCoreApplication::applicationDirPath()).absoluteFilePath(DEFAULT_PORTABLE_MODE_PROFILE_DIR)
         : m_commandLineArgs.profileDir;
-#ifdef Q_OS_WIN
-    const QString instanceId = (profileDir + (m_commandLineArgs.configurationName.isEmpty() ? QString {} : ('/' + m_commandLineArgs.configurationName))).toLower();
-#else
-    const QString instanceId = profileDir + (m_commandLineArgs.configurationName.isEmpty() ? QString {} : ('/' + m_commandLineArgs.configurationName));
-#endif
-    const QString appId = QLatin1String("qBittorrent-") + Utils::Misc::getUserIDString() + '@' + instanceId;
-    m_instanceManager = new ApplicationInstanceManager {appId, this};
-
     Profile::initInstance(profileDir, m_commandLineArgs.configurationName,
                         (m_commandLineArgs.relativeFastresumePaths || portableModeEnabled));
 
+    m_instanceManager = new ApplicationInstanceManager {Profile::instance()->location(SpecialFolder::Config), this};
+
     Logger::initInstance();
     SettingsStorage::initInstance();
     Preferences::initInstance();

src/app/applicationinstancemanager.cpp

@@ -28,24 +28,27 @@
 
 #include "applicationinstancemanager.h"
 
+#include <QtGlobal>
+
 #ifdef Q_OS_WIN
 #include <windows.h>
-#endif
 
 #include <QDebug>
 #include <QSharedMemory>
+#endif
 
 #include "qtlocalpeer/qtlocalpeer.h"
 
-ApplicationInstanceManager::ApplicationInstanceManager(const QString &appId, QObject *parent)
+ApplicationInstanceManager::ApplicationInstanceManager(const QString &instancePath, QObject *parent)
     : QObject {parent}
-    , m_peer {new QtLocalPeer {this, appId}}
+    , m_peer {new QtLocalPeer {instancePath, this}}
     , m_isFirstInstance {!m_peer->isClient()}
 {
     connect(m_peer, &QtLocalPeer::messageReceived, this, &ApplicationInstanceManager::messageReceived);
 
 #ifdef Q_OS_WIN
-    auto sharedMem = new QSharedMemory {appId + QLatin1String {"-shared-memory-key"}, this};
+    const QString sharedMemoryKey = instancePath + QLatin1String {"/shared-memory"};
+    auto sharedMem = new QSharedMemory {sharedMemoryKey, this};
     if (m_isFirstInstance)
     {
         // First instance creates shared memory and store PID
@@ -79,8 +82,3 @@ bool ApplicationInstanceManager::sendMessage(const QString &message, const int t
 {
     return m_peer->sendMessage(message, timeout);
 }
-
-QString ApplicationInstanceManager::appId() const
-{
-    return m_peer->applicationId();
-}

src/app/applicationinstancemanager.h

@@ -32,16 +32,15 @@
 
 class QtLocalPeer;
 
-class ApplicationInstanceManager : public QObject
+class ApplicationInstanceManager final : public QObject
 {
     Q_OBJECT
     Q_DISABLE_COPY_MOVE(ApplicationInstanceManager)
 
 public:
-    explicit ApplicationInstanceManager(const QString &appId, QObject *parent = nullptr);
+    explicit ApplicationInstanceManager(const QString &instancePath, QObject *parent = nullptr);
 
     bool isFirstInstance() const;
-    QString appId() const;
 
 public slots:
     bool sendMessage(const QString &message, int timeout = 5000);

src/app/qtlocalpeer/qtlocalpeer.cpp

@@ -68,20 +68,16 @@
 
 #include "qtlocalpeer.h"
 
-#if defined(Q_OS_UNIX)
+#include <QtGlobal>
-#include <sys/types.h>
+
-#include <time.h>
+#if defined(Q_OS_WIN)
-#include <unistd.h>
+#include <Windows.h>
 #endif
 
-#include <QCoreApplication>
 #include <QDataStream>
-#include <QDir>
+#include <QFileInfo>
 #include <QLocalServer>
 #include <QLocalSocket>
-#include <QRegularExpression>
-
-#include "base/utils/misc.h"
 
 namespace QtLP_Private
 {
@@ -96,41 +92,14 @@ namespace QtLP_Private
 
 const char* QtLocalPeer::ack = "ack";
 
-QtLocalPeer::QtLocalPeer(QObject *parent, const QString &appId)
+QtLocalPeer::QtLocalPeer(const QString &path, QObject *parent)
     : QObject(parent)
-    , id(appId)
+    , socketName(path + QLatin1String("/ipc-socket"))
+    , server(new QLocalServer(this))
 {
-    QString prefix = id;
-    if (id.isEmpty())
-    {
-        id = QCoreApplication::applicationFilePath();
-#if defined(Q_OS_WIN)
-        id = id.toLower();
-#endif
-        prefix = id.section(QLatin1Char('/'), -1);
-    }
-    prefix.remove(QRegularExpression("[^a-zA-Z]"));
-    prefix.truncate(6);
-
-    QByteArray idc = id.toUtf8();
-    quint16 idNum = qChecksum(idc.constData(), idc.size());
-    socketName = QLatin1String("qtsingleapp-") + prefix
-                 + QLatin1Char('-') + QString::number(idNum, 16);
-
-#if defined(Q_OS_WIN)
-    DWORD sessionId = 0;
-    ::ProcessIdToSessionId(GetCurrentProcessId(), &sessionId);
-    socketName += (QLatin1Char('-') + QString::number(sessionId, 16));
-#else
-    socketName += (QLatin1Char('-') + QString::number(::getuid(), 16));
-#endif
-
-    server = new QLocalServer(this);
     server->setSocketOptions(QLocalServer::UserAccessOption);
-    QString lockName = QDir(QDir::tempPath()).absolutePath()
+
-                       + QLatin1Char('/') + socketName
+    lockFile.setFileName(path + QLatin1String("/lockfile"));
-                       + QLatin1String("-lockfile");
-    lockFile.setFileName(lockName);
     lockFile.open(QIODevice::ReadWrite);
 }
 
@@ -156,12 +125,13 @@ bool QtLocalPeer::isClient()
     // ### Workaround
     if (!res && server->serverError() == QAbstractSocket::AddressInUseError)
     {
-        QFile::remove(QDir::cleanPath(QDir::tempPath())+QLatin1Char('/')+socketName);
+        QFile::remove(socketName);
         res = server->listen(socketName);
     }
 #endif
     if (!res)
         qWarning("QtSingleCoreApplication: listen on local socket failed, %s", qPrintable(server->errorString()));
+
     connect(server, &QLocalServer::newConnection, this, &QtLocalPeer::receiveConnection);
     return false;
 }
@@ -204,11 +174,6 @@ bool QtLocalPeer::sendMessage(const QString &message, const int timeout)
     return res;
 }
 
-QString QtLocalPeer::applicationId() const
-{
-    return id;
-}
-
 void QtLocalPeer::receiveConnection()
 {
     QLocalSocket* socket = server->nextPendingConnection();

src/app/qtlocalpeer/qtlocalpeer.h

@@ -68,21 +68,23 @@
 
 #pragma once
 
+#include <QString>
+
 #include "qtlockedfile.h"
 
 class QLocalServer;
 
-class QtLocalPeer : public QObject
+class QtLocalPeer final : public QObject
 {
     Q_OBJECT
+    Q_DISABLE_COPY_MOVE(QtLocalPeer)
 
 public:
-    QtLocalPeer(QObject *parent = nullptr, const QString &appId = QString());
+    QtLocalPeer(const QString &path, QObject *parent = nullptr);
     ~QtLocalPeer() override;
 
     bool isClient();
     bool sendMessage(const QString &message, int timeout);
-    QString applicationId() const;
 
 signals:
     void messageReceived(const QString &message);

src/app/qtlocalpeer/qtlockedfile.h

@@ -71,6 +71,7 @@
 #include <QFile>
 
 #ifdef Q_OS_WIN
+#include <QString>
 #include <QVector>
 #endif