File indexing completed on 2025-03-09 03:54:59

 /* ============================================================
  *
  * This file is a part of digiKam project
  * https://www.digikam.org
  *
  * Date        : 2007-03-18
  * Description : Face database access wrapper.
  *
  * SPDX-FileCopyrightText: 2007-2008 by Marcel Wiesweg <marcel dot wiesweg at gmx dot de>
  * SPDX-FileCopyrightText: 2010-2024 by Gilles Caulier <caulier dot gilles at gmail dot com>
  *
  * SPDX-License-Identifier: GPL-2.0-or-later
  *
  * ============================================================ */
 
 #include "facedbaccess.h"
 
 // Qt includes
 
 #include <QMutex>
 #include <QMutexLocker>
 #include <QSqlDatabase>
 
 // KDE includes
 
 #include <klocalizedstring.h>
 
 // Local includes
 
 #include "digikam_debug.h"
 #include "facedbbackend.h"
 #include "facedb.h"
 #include "facedbschemaupdater.h"
 #include "dbengineaccess.h"
 #include "dbengineerrorhandler.h"
 
 namespace Digikam
 {
 
 class Q_DECL_HIDDEN FaceDbAccessStaticPriv
 {
 public:
 
     explicit FaceDbAccessStaticPriv()
         : backend     (nullptr),
           db          (nullptr),
           initializing(false)
     {
     }
 
     ~FaceDbAccessStaticPriv()
     {
     }
 
 public:
 
     FaceDbBackend*     backend;
     FaceDb*            db;
     DbEngineParameters parameters;
     DbEngineLocking    lock;
     QString            lastError;
     bool               initializing;
 };
 
 FaceDbAccessStaticPriv* FaceDbAccess::d = nullptr;
 
 // -----------------------------------------------------------------------------
 
 class Q_DECL_HIDDEN FaceDbAccessMutexLocker
 
 #if (QT_VERSION >= QT_VERSION_CHECK(6, 0, 0))
 
     : public QMutexLocker<QRecursiveMutex>
 
 #else
 
     : public QMutexLocker
 
 #endif
 
 {
 public:
 
     explicit FaceDbAccessMutexLocker(FaceDbAccessStaticPriv* const dd)
         : QMutexLocker(&dd->lock.mutex),
           d           (dd)
     {
         d->lock.lockCount++;
     }
 
     ~FaceDbAccessMutexLocker()
     {
         d->lock.lockCount--;
     }
 
 public:
 
     FaceDbAccessStaticPriv* const d;
 };
 
 // -----------------------------------------------------------------------------
 
 FaceDbAccess::FaceDbAccess()
 {
     // You will want to call setParameters before constructing FaceDbAccess.
 
     Q_ASSERT(d);
 
     d->lock.mutex.lock();
     d->lock.lockCount++;
 
     if (!d->backend->isOpen() && !d->initializing)
     {
         // avoid endless loops
 
         d->initializing = true;
         d->backend->open(d->parameters);
         d->initializing = false;
     }
 }
 
 FaceDbAccess::~FaceDbAccess()
 {
     d->lock.lockCount--;
     d->lock.mutex.unlock();
 }
 
 FaceDbAccess::FaceDbAccess(bool)
 {
     // private constructor, when mutex is locked and
     // backend should not be checked
 
     d->lock.mutex.lock();
     d->lock.lockCount++;
 }
 
 FaceDb* FaceDbAccess::db() const
 {
     return d->db;
 }
 
 FaceDbBackend* FaceDbAccess::backend() const
 {
     return d->backend;
 }
 
 DbEngineParameters FaceDbAccess::parameters()
 {
     if (d)
     {
         return d->parameters;
     }
 
     return DbEngineParameters();
 }
 
 bool FaceDbAccess::isInitialized()
 {
     return d;
 }
 
 void FaceDbAccess::initDbEngineErrorHandler(DbEngineErrorHandler* const errorhandler)
 {
     if (!d)
     {
         d = new FaceDbAccessStaticPriv();
     }
 /*
     DbEngineErrorHandler* const errorhandler = new DbEngineGuiErrorHandler(d->parameters);
 */
     d->backend->setDbEngineErrorHandler(errorhandler);
 }
 
 void FaceDbAccess::setParameters(const DbEngineParameters& parameters)
 {
     if (!d)
     {
         d = new FaceDbAccessStaticPriv();
     }
 
     FaceDbAccessMutexLocker lock(d);
 
     if (d->parameters == parameters)
     {
         return;
     }
 
     if (d->backend && d->backend->isOpen())
     {
         d->backend->close();
     }
 
     // Kill the old database error handler
 
     if (d->backend)
     {
         d->backend->setDbEngineErrorHandler(nullptr);
     }
 
     d->parameters = parameters;
 
     if (!d->backend || !d->backend->isCompatible(parameters))
     {
         delete d->db;
         delete d->backend;
         d->backend = new FaceDbBackend(&d->lock);
         d->db      = new FaceDb(d->backend);
     }
 }
 
 bool FaceDbAccess::checkReadyForUse(InitializationObserver* const observer)
 {
     if (!DbEngineAccess::checkReadyForUse(d->lastError))
     {
         return false;
     }
 
     // Create an object with private shortcut constructor
 
     FaceDbAccess access(false);
 
     if (!d->backend)
     {
         qCWarning(DIGIKAM_FACEDB_LOG) << "Face database: no database backend available in checkReadyForUse. "
                                          "Did you call setParameters before?";
         return false;
     }
 
     if (d->backend->isReady())
     {
         return true;
     }
 
     if (!d->backend->isOpen())
     {
         if (!d->backend->open(d->parameters))
         {
             access.setLastError(i18n("Error opening database backend.\n%1",
                                      d->backend->lastError()));
             return false;
         }
     }
 
     // Avoid endless loops (if called methods create new FaceDbAccess objects)
 
     d->initializing = true;
 
     // Update schema
 
     FaceDbSchemaUpdater updater(&access);
     updater.setObserver(observer);
 
     // Check or set WAL mode for SQLite database from DbEngineParameters
 
     d->backend->checkOrSetWALMode();
 
     if (!d->backend->initSchema(&updater))
     {
         qCWarning(DIGIKAM_FACEDB_LOG) << "Face database: cannot process schema initialization";
 
         d->initializing = false;
         return false;
     }
 
     d->initializing = false;
 
     return d->backend->isReady();
 }
 
 QString FaceDbAccess::lastError() const
 {
     return d->lastError;
 }
 
 void FaceDbAccess::setLastError(const QString& error)
 {
     d->lastError = error;
 }
 
 void FaceDbAccess::cleanUpDatabase()
 {
     if (d)
     {
         FaceDbAccessMutexLocker locker(d);
 
         if (d->backend)
         {
             d->backend->close();
             delete d->db;
             delete d->backend;
         }
     }
 
     delete d;
     d = nullptr;
 }
 
 // ---------------------------------------------------------------------------------
 
 FaceDbAccessUnlock::FaceDbAccessUnlock()
 {
     // acquire lock
 
     FaceDbAccess::d->lock.mutex.lock();
 
     // store lock count
 
     count = FaceDbAccess::d->lock.lockCount;
 
     // set lock count to 0
 
     FaceDbAccess::d->lock.lockCount = 0;
 
     // unlock
 
     for (int i = 0 ; i < count ; ++i)
     {
         FaceDbAccess::d->lock.mutex.unlock();
     }
 
     // drop lock acquired in first line. Mutex is now free.
 
     FaceDbAccess::d->lock.mutex.unlock();
 }
 
 FaceDbAccessUnlock::FaceDbAccessUnlock(FaceDbAccess* const)
 {
     // With the passed pointer, we have assured that the mutex is acquired
     // Store lock count
 
     count = FaceDbAccess::d->lock.lockCount;
 
     // set lock count to 0
 
     FaceDbAccess::d->lock.lockCount = 0;
 
     // unlock
 
     for (int i = 0 ; i < count ; ++i)
     {
         FaceDbAccess::d->lock.mutex.unlock();
     }
 
     // Mutex is now free
 }
 
 FaceDbAccessUnlock::~FaceDbAccessUnlock()
 {
     // lock as often as it was locked before
 
     for (int i = 0 ; i < count ; ++i)
     {
         FaceDbAccess::d->lock.mutex.lock();
     }
 
     // update lock count
 
     FaceDbAccess::d->lock.lockCount += count;
 }
 
 } // namespace Digikam