diff --git a/shell/sessionlock.cpp b/shell/sessionlock.cpp index 719d0d4d00..2113c1cdce 100644 --- a/shell/sessionlock.cpp +++ b/shell/sessionlock.cpp @@ -1,216 +1,216 @@ /* * This file is part of KDevelop * Copyright 2013 Milian Wolff * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) version 3, or any * later version accepted by the membership of KDE e.V. (or its * successor approved by the membership of KDE e.V.), which shall * act as a proxy defined in Section 6 of version 3 of the license. * * This library 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 * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library. If not, see . */ #include "sessionlock.h" #include "sessioncontroller.h" #include #include #include #include #include using namespace KDevelop; namespace { QString lockFileForSession( const QString& id ) { return SessionController::sessionDirectory( id ) + "/lock"; } QString dBusServiceNameForSession( const QString& id ) { // We remove starting "{" and ending "}" from the string UUID representation // as D-Bus apparently doesn't allow them in service names return QStringLiteral( "org.kdevelop.kdevplatform-lock-" ) + QString( id ).mid( 1, id.size() - 2 ); } /// Force-removes the lock-file. void forceRemoveLockfile(const QString& lockFilename) { if( QFile::exists( lockFilename ) ) { QFile::remove( lockFilename ); } } } TryLockSessionResult SessionLock::tryLockSession(const QString& sessionId, bool doLocking) { ///FIXME: if this is hit, someone tried to lock a non-existing session /// this should be fixed by using a proper data type distinct from /// QString for id's, i.e. QUuid or similar. Q_ASSERT(QFile::exists(SessionController::sessionDirectory( sessionId ))); /* * We've got two locking mechanisms here: D-Bus unique service name (based on the session id) * and a plain lockfile (QLockFile). * The latter is required to get the appname/pid of the locking instance * in case if it's stale/hanging/crashed (to make user know which PID he needs to kill). * D-Bus mechanism is the primary one. * * Since there is a kind of "logic tree", the code is a bit hard. */ const QString service = dBusServiceNameForSession( sessionId ); QDBusConnection connection = QDBusConnection::sessionBus(); QDBusConnectionInterface* connectionInterface = connection.interface(); const QString lockFilename = lockFileForSession( sessionId ); QSharedPointer lockFile(new QLockFile( lockFilename )); - bool canLockDBus = !connectionInterface->isServiceRegistered( service ); + bool canLockDBus = connectionInterface && !connectionInterface->isServiceRegistered( service ); bool lockedDBus = false; // Lock D-Bus if we can and we need to if( doLocking && canLockDBus ) { lockedDBus = connection.registerService( service ); } // Attempt to lock file, despite the possibility to do so and presence of the request (doLocking) // This is required as QLockFile::getLockInfo() works only after QLockFile::lock() is called bool lockResult = lockFile->tryLock(); SessionRunInfo runInfo; if (lockResult) { // Unlock immediately if we shouldn't have locked it if( !lockedDBus ) { lockFile->unlock(); } } else { // If locking failed, retrieve the lock's metadata lockFile->getLockInfo(&runInfo.holderPid, &runInfo.holderHostname, &runInfo.holderApp ); if( lockedDBus ) { // Since the lock-file is secondary, try to force-lock it if D-Bus locking succeeded forceRemoveLockfile(lockFilename); lockResult = lockFile->tryLock(); Q_ASSERT(lockResult); } } // Set the result by D-Bus status if (doLocking && lockedDBus) { return TryLockSessionResult(QSharedPointer(new SessionLock(sessionId, lockFile))); } else { runInfo.isRunning = !canLockDBus; return TryLockSessionResult(runInfo); } } QString SessionLock::id() { return m_sessionId; } SessionLock::SessionLock(const QString& sessionId, const QSharedPointer& lockFile) : m_sessionId(sessionId) , m_lockFile(lockFile) { Q_ASSERT(lockFile->isLocked()); } SessionLock::~SessionLock() { m_lockFile->unlock(); bool unregistered = QDBusConnection::sessionBus().unregisterService( dBusServiceNameForSession(m_sessionId) ); Q_ASSERT(unregistered); Q_UNUSED(unregistered); } QString SessionLock::handleLockedSession(const QString& sessionName, const QString& sessionId, const SessionRunInfo& runInfo) { if( !runInfo.isRunning ) { return sessionId; } // try to make the locked session active { // The timeout for "ensureVisible" call // Leave it sufficiently low to avoid waiting for hung instances. static const int timeout_ms = 1000; QDBusMessage message = QDBusMessage::createMethodCall( dBusServiceNameForSession(sessionId), "/kdevelop/MainWindow", "org.kdevelop.MainWindow", "ensureVisible" ); QDBusMessage reply = QDBusConnection::sessionBus().call( message, QDBus::Block, timeout_ms ); if( reply.type() == QDBusMessage::ReplyMessage ) { QTextStream out(stdout); out << i18nc( "@info:shell", "made running %1 instance (PID: %2) visible", runInfo.holderApp, runInfo.holderPid ) << endl; return QString(); } else { qWarning() << i18nc("@info:shell", "running %1 instance (PID: %2) is apparently hung", runInfo.holderApp, runInfo.holderPid); } } // otherwise ask the user whether we should retry QString problemDescription = i18nc("@info", "The given application did not respond to a DBUS call, " "it may have crashed or is hanging."); QString problemHeader; if( runInfo.holderPid != -1 ) { problemHeader = i18nc("@info", "Failed to lock the session %1, " "already locked by %2 on %3 (PID %4).", sessionName, runInfo.holderApp, runInfo.holderHostname, runInfo.holderPid); } else { problemHeader = i18nc("@info", "Failed to lock the session %1 (lock-file unavailable).", sessionName); } QString problemResolution = i18nc("@info", "

Please, close the offending application instance " "or choose another session to launch.

"); QString errmsg = "

" + problemHeader + "
" + problemDescription + "

" + problemResolution; KGuiItem retry = KStandardGuiItem::cont(); retry.setText(i18nc("@action:button", "Retry startup")); KGuiItem choose = KStandardGuiItem::configure(); choose.setText(i18nc("@action:button", "Choose another session")); KGuiItem cancel = KStandardGuiItem::quit(); int ret = KMessageBox::warningYesNoCancel(0, errmsg, i18nc("@title:window", "Failed to Lock Session %1", sessionName), retry, choose, cancel); switch( ret ) { case KMessageBox::Yes: return sessionId; break; case KMessageBox::No: { QString errmsg = i18nc("@info", "The session %1 is already active in another running instance.", sessionName); return SessionController::showSessionChooserDialog(errmsg); break; } case KMessageBox::Cancel: default: break; } return QString(); }