File indexing completed on 2024-05-12 04:59:34

 /*
  *   SPDX-FileCopyrightText: 2014-2016 Ivan Cukic <ivan.cukic@kde.org>
  *
  *   SPDX-License-Identifier: GPL-2.0-only OR GPL-3.0-only OR LicenseRef-KDE-Accepted-GPL
  */
 
 #include "Database.h"
 
 #include <common/database/schema/ResourcesDatabaseSchema.h>
 #include <utils/d_ptr_implementation.h>
 
 #include <QDebug>
 #include <QSqlDatabase>
 #include <QSqlDriver>
 #include <QSqlError>
 #include <QSqlField>
 #include <QThread>
 
 #include <map>
 #include <mutex>
 
 namespace Common
 {
 
 namespace
 {
 #ifdef QT_DEBUG
 QString lastExecutedQuery;
 #endif
 
 std::mutex databases_mutex;
 
 struct DatabaseInfo {
     Qt::HANDLE thread;
     Database::OpenMode openMode;
 };
 
 bool operator<(const DatabaseInfo &left, const DatabaseInfo &right)
 {
     return left.thread < right.thread ? true : left.thread > right.thread ? false : left.openMode < right.openMode;
 }
 
 std::map<DatabaseInfo, std::weak_ptr<Database>> databases;
 };
 
 class QSqlDatabaseWrapper
 {
 private:
     QSqlDatabase m_database;
     bool m_open;
     QString m_connectionName;
 
 public:
     QSqlDatabaseWrapper(const DatabaseInfo &info)
         : m_open(false)
     {
         m_connectionName = "kactivities_db_resources_"
             // Adding the thread number to the database name
             + QString::number((quintptr)info.thread)
             // And whether it is read-only or read-write
             + (info.openMode == Database::ReadOnly ? "_readonly" : "_readwrite");
 
         m_database = QSqlDatabase::contains(m_connectionName) ? QSqlDatabase::database(m_connectionName)
                                                               : QSqlDatabase::addDatabase(QStringLiteral("QSQLITE"), m_connectionName);
 
         if (info.openMode == Database::ReadOnly) {
             m_database.setConnectOptions(QStringLiteral("QSQLITE_OPEN_READONLY"));
         }
 
         // We are allowing the database file to be overridden mostly for testing purposes
         m_database.setDatabaseName(ResourcesDatabaseSchema::path());
 
         m_open = m_database.open();
 
         if (!m_open) {
             qWarning() << "KActivities: Database is not open: " << m_database.connectionName() << m_database.databaseName() << m_database.lastError();
 
             if (info.openMode == Database::ReadWrite) {
                 qFatal("KActivities: Opening the database in RW mode should always succeed");
             }
         }
     }
 
     ~QSqlDatabaseWrapper()
     {
         qDebug() << "Closing SQL connection: " << m_connectionName;
     }
 
     QSqlDatabase &get()
     {
         return m_database;
     }
 
     bool isOpen() const
     {
         return m_open;
     }
 
     QString connectionName() const
     {
         return m_connectionName;
     }
 };
 
 class Database::Private
 {
 public:
     Private()
     {
     }
 
     QSqlQuery query(const QString &query)
     {
         return database ? QSqlQuery(query, database->get()) : QSqlQuery();
     }
 
     QSqlQuery query()
     {
         return database ? QSqlQuery(database->get()) : QSqlQuery();
     }
 
     QScopedPointer<QSqlDatabaseWrapper> database;
 };
 
 Database::Locker::Locker(Database &database)
     : m_database(database.d->database->get())
 {
     m_database.transaction();
 }
 
 Database::Locker::~Locker()
 {
     m_database.commit();
 }
 
 Database::Ptr Database::instance(Source source, OpenMode openMode)
 {
     Q_UNUSED(source) // for the time being
 
     std::lock_guard<std::mutex> lock(databases_mutex);
 
     // We are saving instances per thread and per read/write mode
     DatabaseInfo info;
     info.thread = QThread::currentThreadId();
     info.openMode = openMode;
 
     // Do we have an instance matching the request?
     auto search = databases.find(info);
     if (search != databases.end()) {
         auto ptr = search->second.lock();
 
         if (ptr) {
             return ptr;
         }
     }
 
     // Creating a new database instance
     auto ptr = std::make_shared<Database>();
 
     ptr->d->database.reset(new QSqlDatabaseWrapper(info));
 
     if (!ptr->d->database->isOpen()) {
         return nullptr;
     }
 
     databases[info] = ptr;
 
     if (info.openMode == ReadOnly) {
         // From now on, only SELECT queries will work
         ptr->setPragma(QStringLiteral("query_only = 1"));
 
         // These should not make any difference
         ptr->setPragma(QStringLiteral("synchronous = 0"));
 
     } else {
         // Using the write-ahead log and sync = NORMAL for faster writes
         ptr->setPragma(QStringLiteral("synchronous = 1"));
     }
 
     // Maybe we should use the write-ahead log
     auto walResult = ptr->pragma(QStringLiteral("journal_mode = WAL"));
 
     if (walResult != "wal") {
         qFatal(
             "KActivities: Database can not be opened in WAL mode. Check the "
             "SQLite version (required >3.7.0). And whether your filesystem "
             "supports shared memory");
     }
 
     // We don't have a big database, lets flush the WAL when
     // it reaches 400k, not 4M as is default
     ptr->setPragma(QStringLiteral("wal_autocheckpoint = 100"));
 
     qDebug() << "KActivities: Database connection: " << ptr->d->database->connectionName()
              << "\n    query_only:         " << ptr->pragma(QStringLiteral("query_only"))
              << "\n    journal_mode:       " << ptr->pragma(QStringLiteral("journal_mode"))
              << "\n    wal_autocheckpoint: " << ptr->pragma(QStringLiteral("wal_autocheckpoint"))
              << "\n    synchronous:        " << ptr->pragma(QStringLiteral("synchronous"));
 
     return ptr;
 }
 
 Database::Database()
 {
 }
 
 Database::~Database()
 {
 }
 
 QSqlQuery Database::createQuery() const
 {
     return d->query();
 }
 
 QString Database::lastQuery() const
 {
 #ifdef QT_DEBUG
     return lastExecutedQuery;
 #endif
     return QString();
 }
 
 QSqlQuery Database::execQuery(const QString &query, bool ignoreErrors) const
 {
 #ifdef QT_NO_DEBUG
     return d->query(query);
 #else
     auto result = d->query(query);
 
     lastExecutedQuery = query;
 
     if (!ignoreErrors && result.lastError().isValid()) {
         qWarning() << "SQL: "
                    << "\n    error: " << result.lastError() << "\n    query: " << query;
     }
 
     return result;
 #endif
 }
 
 QSqlQuery Database::execQueries(const QStringList &queries) const
 {
     QSqlQuery result;
 
     for (const auto &query : queries) {
         result = execQuery(query);
     }
 
     return result;
 }
 
 void Database::setPragma(const QString &pragma)
 {
     execQuery(QStringLiteral("PRAGMA ") + pragma);
 }
 
 QVariant Database::pragma(const QString &pragma) const
 {
     return value("PRAGMA " + pragma);
 }
 
 QVariant Database::value(const QString &query) const
 {
     auto result = execQuery(query);
     return result.next() ? result.value(0) : QVariant();
 }
 
 } // namespace Common