qsql_sqlite.cpp

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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
// Qt-Security score:critical reason:data-parser
 
#include "qsql_sqlite_p.h"
 
#include <qcoreapplication.h>
#include <qdatetime.h>
#include <qdebug.h>
#include <qlist.h>
#include <qloggingcategory.h>
#include <qsqlerror.h>
#include <qsqlfield.h>
#include <qsqlindex.h>
#include <qsqlquery.h>
#include <QtSql/private/qsqlcachedresult_p.h>
#include <QtSql/private/qsqldriver_p.h>
#include <qstringlist.h>
#include <qvariant.h>
#if QT_CONFIG(regularexpression)
#include <qcache.h>
#include <qregularexpression.h>
#endif
#include <QScopedValueRollback>
 
#if defined Q_OS_WIN
# include <qt_windows.h>
#else
# include <unistd.h>
#endif
 
#include <sqlite3.h>
#include <functional>
 
Q_DECLARE_OPAQUE_POINTER(sqlite3*)
Q_DECLARE_METATYPE(sqlite3*)
 
Q_DECLARE_OPAQUE_POINTER(sqlite3_stmt*)
Q_DECLARE_METATYPE(sqlite3_stmt*)
 
QT_BEGIN_NAMESPACE
 
Q_STATIC_LOGGING_CATEGORY(lcSqlite, "qt.sql.sqlite")
 
using namespace Qt::StringLiterals;
 
static int qGetColumnType(const QString &tpName)
{
    if (tpName.compare("integer"_L1, Qt::CaseInsensitive) == 0 || tpName.compare("int"_L1, Qt::CaseInsensitive) == 0)
        return QMetaType::Int;
    if (tpName.compare("double"_L1, Qt::CaseInsensitive) == 0
        || tpName.compare("float"_L1, Qt::CaseInsensitive) == 0
        || tpName.compare("real"_L1, Qt::CaseInsensitive) == 0
        || tpName.startsWith("numeric"_L1, Qt::CaseInsensitive))
        return QMetaType::Double;
    if (tpName.compare("blob"_L1, Qt::CaseInsensitive) == 0)
        return QMetaType::QByteArray;
    if (tpName.compare("boolean"_L1, Qt::CaseInsensitive) == 0 || tpName.compare("bool"_L1, Qt::CaseInsensitive) == 0)
        return QMetaType::Bool;
    return QMetaType::QString;
}
 
static QSqlError qMakeError(sqlite3 *access, const QString &descr, QSqlError::ErrorType type,
                            int errorCode)
{
    return QSqlError(descr,
                     QString(reinterpret_cast<const QChar *>(sqlite3_errmsg16(access))),
                     type, QString::number(errorCode));
}
 
class QSQLiteResultPrivate;
 
class QSQLiteResult : public QSqlCachedResult
{
    Q_DECLARE_PRIVATE(QSQLiteResult)
    friend class QSQLiteDriver;
 
public:
    explicit QSQLiteResult(const QSQLiteDriver* db);
    ~QSQLiteResult();
    QVariant handle() const override;
 
protected:
    bool gotoNext(QSqlCachedResult::ValueCache& row, int idx) override;
    bool reset(const QString &query) override;
    bool prepare(const QString &query) override;
    bool execBatch(bool arrayBind) override;
    bool exec() override;
    int size() override;
    int numRowsAffected() override;
    QVariant lastInsertId() const override;
    QSqlRecord record() const override;
    void detachFromResultSet() override;
    void virtual_hook(int id, void *data) override;
};
 
class QSQLiteDriverPrivate : public QSqlDriverPrivate
{
    Q_DECLARE_PUBLIC(QSQLiteDriver)
 
public:
    inline QSQLiteDriverPrivate() : QSqlDriverPrivate(QSqlDriver::SQLite) {}
    bool isIdentifierEscaped(QStringView identifier) const;
    QSqlIndex getTableInfo(QSqlQuery &query, const QString &tableName,
                           bool onlyPIndex = false) const;
 
    sqlite3 *access = nullptr;
    QList<QSQLiteResult *> results;
    QStringList notificationid;
};
 
bool QSQLiteDriverPrivate::isIdentifierEscaped(QStringView identifier) const
{
    return identifier.size() > 2
            && ((identifier.startsWith(u'"') && identifier.endsWith(u'"'))
                || (identifier.startsWith(u'`') && identifier.endsWith(u'`'))
                || (identifier.startsWith(u'[') && identifier.endsWith(u']')));
}
 
QSqlIndex QSQLiteDriverPrivate::getTableInfo(QSqlQuery &query, const QString &tableName,
                                             bool onlyPIndex) const
{
    Q_Q(const QSQLiteDriver);
    QString schema;
    QString table = q->escapeIdentifier(tableName, QSqlDriver::TableName);
    const auto indexOfSeparator = table.indexOf(u'.');
    if (indexOfSeparator > -1) {
        auto leftName = QStringView{table}.first(indexOfSeparator);
        auto rightName = QStringView{table}.sliced(indexOfSeparator + 1);
        if (isIdentifierEscaped(leftName) && isIdentifierEscaped(rightName)) {
            schema = leftName.toString() + u'.';
            table = rightName.toString();
        }
    }
 
    query.exec("PRAGMA "_L1 + schema + "table_xinfo ("_L1 + table + u')');
    QSqlIndex ind;
    while (query.next()) {
        bool isPk = query.value(5).toInt();
        if (onlyPIndex && !isPk)
            continue;
        QString typeName = query.value(2).toString().toLower();
        QString defVal = query.value(4).toString();
        if (!defVal.isEmpty() && defVal.at(0) == u'\'') {
            const int end = defVal.lastIndexOf(u'\'');
            if (end > 0)
                defVal = defVal.mid(1, end - 1);
        }
 
        QSqlField fld(query.value(1).toString(), QMetaType(qGetColumnType(typeName)), tableName);
        if (isPk && (typeName == "integer"_L1))
            // INTEGER PRIMARY KEY fields are auto-generated in sqlite
            // INT PRIMARY KEY is not the same as INTEGER PRIMARY KEY!
            fld.setAutoValue(true);
        fld.setRequired(query.value(3).toInt() != 0);
        fld.setDefaultValue(defVal);
        ind.append(fld);
    }
    return ind;
}
 
class QSQLiteResultPrivate : public QSqlCachedResultPrivate
{
    Q_DECLARE_PUBLIC(QSQLiteResult)
 
public:
    Q_DECLARE_SQLDRIVER_PRIVATE(QSQLiteDriver)
    using QSqlCachedResultPrivate::QSqlCachedResultPrivate;
    void cleanup();
    bool fetchNext(QSqlCachedResult::ValueCache &values, int idx, bool initialFetch);
    // initializes the recordInfo and the cache
    void initColumns(bool emptyResultset);
    void finalize();
 
    sqlite3_stmt *stmt = nullptr;
    QSqlRecord rInf;
    QList<QVariant> firstRow;
    bool skippedStatus = false; // the status of the fetchNext() that's skipped
    bool skipRow = false; // skip the next fetchNext()?
};
 
void QSQLiteResultPrivate::cleanup()
{
    Q_Q(QSQLiteResult);
    finalize();
    rInf.clear();
    skippedStatus = false;
    skipRow = false;
    q->setAt(QSql::BeforeFirstRow);
    q->setActive(false);
    q->cleanup();
}
 
void QSQLiteResultPrivate::finalize()
{
    if (!stmt)
        return;
 
    sqlite3_finalize(stmt);
    stmt = nullptr;
}
 
void QSQLiteResultPrivate::initColumns(bool emptyResultset)
{
    Q_Q(QSQLiteResult);
    int nCols = sqlite3_column_count(stmt);
    if (nCols <= 0)
        return;
 
    q->init(nCols);
 
    for (int i = 0; i < nCols; ++i) {
        QString colName = QString(reinterpret_cast<const QChar *>(
                    sqlite3_column_name16(stmt, i))
                    ).remove(u'"');
        const QString tableName = QString(reinterpret_cast<const QChar *>(
                            sqlite3_column_table_name16(stmt, i))
                            ).remove(u'"');
        // must use typeName for resolving the type to match QSqliteDriver::record
        QString typeName = QString(reinterpret_cast<const QChar *>(
                    sqlite3_column_decltype16(stmt, i)));
        // sqlite3_column_type is documented to have undefined behavior if the result set is empty
        int stp = emptyResultset ? -1 : sqlite3_column_type(stmt, i);
 
        int fieldType;
 
        if (!typeName.isEmpty()) {
            fieldType = qGetColumnType(typeName);
        } else {
            // Get the proper type for the field based on stp value
            switch (stp) {
            case SQLITE_INTEGER:
                fieldType = QMetaType::Int;
                break;
            case SQLITE_FLOAT:
                fieldType = QMetaType::Double;
                break;
            case SQLITE_BLOB:
                fieldType = QMetaType::QByteArray;
                break;
            case SQLITE_TEXT:
                fieldType = QMetaType::QString;
                break;
            case SQLITE_NULL:
            default:
                fieldType = QMetaType::UnknownType;
                break;
            }
        }
 
        QSqlField fld(colName, QMetaType(fieldType), tableName);
        rInf.append(fld);
    }
}
 
bool QSQLiteResultPrivate::fetchNext(QSqlCachedResult::ValueCache &values, int idx, bool initialFetch)
{
    Q_Q(QSQLiteResult);
 
    if (skipRow) {
        // already fetched
        Q_ASSERT(!initialFetch);
        skipRow = false;
        for(int i=0;i<firstRow.size();i++)
            values[i]=firstRow[i];
        return skippedStatus;
    }
    skipRow = initialFetch;
 
    if (initialFetch) {
        firstRow.clear();
        firstRow.resize(sqlite3_column_count(stmt));
    }
 
    if (!stmt) {
        q->setLastError(QSqlError(QCoreApplication::translate("QSQLiteResult", "Unable to fetch row"),
                                  QCoreApplication::translate("QSQLiteResult", "No query"), QSqlError::ConnectionError));
        q->setAt(QSql::AfterLastRow);
        return false;
    }
    int res = sqlite3_step(stmt);
    switch(res) {
    case SQLITE_ROW:
        // check to see if should fill out columns
        if (rInf.isEmpty())
            // must be first call.
            initColumns(false);
        if (idx < 0 && !initialFetch)
            return true;
        for (int i = 0; i < rInf.count(); ++i) {
            switch (sqlite3_column_type(stmt, i)) {
            case SQLITE_BLOB:
                values[i + idx] = QByteArray(static_cast<const char *>(
                            sqlite3_column_blob(stmt, i)),
                            sqlite3_column_bytes(stmt, i));
                break;
            case SQLITE_INTEGER:
                values[i + idx] = sqlite3_column_int64(stmt, i);
                break;
            case SQLITE_FLOAT:
                switch(q->numericalPrecisionPolicy()) {
                    case QSql::LowPrecisionInt32:
                        values[i + idx] = sqlite3_column_int(stmt, i);
                        break;
                    case QSql::LowPrecisionInt64:
                        values[i + idx] = sqlite3_column_int64(stmt, i);
                        break;
                    case QSql::LowPrecisionDouble:
                    case QSql::HighPrecision:
                    default:
                        values[i + idx] = sqlite3_column_double(stmt, i);
                        break;
                };
                break;
            case SQLITE_NULL:
                values[i + idx] = QVariant(QMetaType::fromType<QString>());
                break;
            default:
                values[i + idx] = QString(reinterpret_cast<const QChar *>(
                            sqlite3_column_text16(stmt, i)),
                            sqlite3_column_bytes16(stmt, i) / sizeof(QChar));
                break;
            }
        }
        return true;
    case SQLITE_DONE:
        if (rInf.isEmpty())
            // must be first call.
            initColumns(true);
        q->setAt(QSql::AfterLastRow);
        sqlite3_reset(stmt);
        return false;
    case SQLITE_CONSTRAINT:
    case SQLITE_ERROR:
        // SQLITE_ERROR is a generic error code and we must call sqlite3_reset()
        // to get the specific error message.
        res = sqlite3_reset(stmt);
        q->setLastError(qMakeError(drv_d_func()->access, QCoreApplication::translate("QSQLiteResult",
                        "Unable to fetch row"), QSqlError::ConnectionError, res));
        q->setAt(QSql::AfterLastRow);
        return false;
    case SQLITE_MISUSE:
    case SQLITE_BUSY:
    default:
        // something wrong, don't get col info, but still return false
        q->setLastError(qMakeError(drv_d_func()->access, QCoreApplication::translate("QSQLiteResult",
                        "Unable to fetch row"), QSqlError::ConnectionError, res));
        sqlite3_reset(stmt);
        q->setAt(QSql::AfterLastRow);
        return false;
    }
    return false;
}
 
QSQLiteResult::QSQLiteResult(const QSQLiteDriver* db)
    : QSqlCachedResult(*new QSQLiteResultPrivate(this, db))
{
    Q_D(QSQLiteResult);
    const_cast<QSQLiteDriverPrivate*>(d->drv_d_func())->results.append(this);
}
 
QSQLiteResult::~QSQLiteResult()
{
    Q_D(QSQLiteResult);
    if (d->drv_d_func())
        const_cast<QSQLiteDriverPrivate*>(d->drv_d_func())->results.removeOne(this);
    d->cleanup();
}
 
void QSQLiteResult::virtual_hook(int id, void *data)
{
    QSqlCachedResult::virtual_hook(id, data);
}
 
bool QSQLiteResult::reset(const QString &query)
{
    if (!prepare(query))
        return false;
    return exec();
}
 
bool QSQLiteResult::prepare(const QString &query)
{
    Q_D(QSQLiteResult);
    if (!driver() || !driver()->isOpen() || driver()->isOpenError())
        return false;
 
    d->cleanup();
 
    setSelect(false);
 
    const void *pzTail = nullptr;
    const auto size = int((query.size() + 1) * sizeof(QChar));
 
#if (SQLITE_VERSION_NUMBER >= 3003011)
    int res = sqlite3_prepare16_v2(d->drv_d_func()->access, query.constData(), size,
                                   &d->stmt, &pzTail);
#else
    int res = sqlite3_prepare16(d->access, query.constData(), size,
                                &d->stmt, &pzTail);
#endif
 
    if (res != SQLITE_OK) {
        setLastError(qMakeError(d->drv_d_func()->access, QCoreApplication::translate("QSQLiteResult",
                     "Unable to execute statement"), QSqlError::StatementError, res));
        d->finalize();
        return false;
    } else if (pzTail && !QString(reinterpret_cast<const QChar *>(pzTail)).trimmed().isEmpty()) {
        setLastError(qMakeError(d->drv_d_func()->access, QCoreApplication::translate("QSQLiteResult",
            "Unable to execute multiple statements at a time"), QSqlError::StatementError, SQLITE_MISUSE));
        d->finalize();
        return false;
    }
    return true;
}
 
bool QSQLiteResult::execBatch(bool arrayBind)
{
    Q_UNUSED(arrayBind);
    Q_D(QSqlResult);
    QScopedValueRollback<QList<QVariant>> valuesScope(d->values);
    QList<QVariant> values = d->values;
    if (values.size() == 0)
        return false;
 
    for (int i = 0; i < values.at(0).toList().size(); ++i) {
        d->values.clear();
        QScopedValueRollback<QHash<QString, QList<int>>> indexesScope(d->indexes);
        auto it = d->indexes.constBegin();
        while (it != d->indexes.constEnd()) {
            bindValue(it.key(), values.at(it.value().first()).toList().at(i), QSql::In);
            ++it;
        }
        if (!exec())
            return false;
    }
    return true;
}
 
bool QSQLiteResult::exec()
{
    Q_D(QSQLiteResult);
    QList<QVariant> values = boundValues();
 
    d->skippedStatus = false;
    d->skipRow = false;
    d->rInf.clear();
    clearValues();
    setLastError(QSqlError());
 
    int res = sqlite3_reset(d->stmt);
    if (res != SQLITE_OK) {
        setLastError(qMakeError(d->drv_d_func()->access, QCoreApplication::translate("QSQLiteResult",
                     "Unable to reset statement"), QSqlError::StatementError, res));
        d->finalize();
        return false;
    }
 
    int paramCount = sqlite3_bind_parameter_count(d->stmt);
    bool paramCountIsValid = paramCount == values.size();
 
#if (SQLITE_VERSION_NUMBER >= 3003011)
    // In the case of the reuse of a named placeholder
    // We need to check explicitly that paramCount is greater than or equal to 1, as sqlite
    // can end up in a case where for virtual tables it returns 0 even though it
    // has parameters
    if (paramCount >= 1 && paramCount < values.size()) {
        const auto countIndexes = [](int counter, const QList<int> &indexList) {
                                      return counter + indexList.size();
                                  };
 
        const int bindParamCount = std::accumulate(d->indexes.cbegin(),
                                                   d->indexes.cend(),
                                                   0,
                                                   countIndexes);
 
        paramCountIsValid = bindParamCount == values.size();
        // When using named placeholders, it will reuse the index for duplicated
        // placeholders. So we need to ensure the QList has only one instance of
        // each value as SQLite will do the rest for us.
        QList<QVariant> prunedValues;
        QList<int> handledIndexes;
        for (int i = 0, currentIndex = 0; i < values.size(); ++i) {
            if (handledIndexes.contains(i))
                continue;
            const char *parameterName = sqlite3_bind_parameter_name(d->stmt, currentIndex + 1);
            if (!parameterName) {
                paramCountIsValid = false;
                continue;
            }
            const auto placeHolder = QString::fromUtf8(parameterName);
            const auto &indexes = d->indexes.value(placeHolder);
            handledIndexes << indexes;
            prunedValues << values.at(indexes.first());
            ++currentIndex;
        }
        values = prunedValues;
    }
#endif
 
    if (paramCountIsValid) {
        for (int i = 0; i < paramCount; ++i) {
            res = SQLITE_OK;
            const QVariant &value = values.at(i);
 
            if (QSqlResultPrivate::isVariantNull(value)) {
                res = sqlite3_bind_null(d->stmt, i + 1);
            } else {
                switch (value.userType()) {
                case QMetaType::QByteArray: {
                    const QByteArray *ba = static_cast<const QByteArray*>(value.constData());
                    res = sqlite3_bind_blob(d->stmt, i + 1, ba->constData(),
                                            ba->size(), SQLITE_STATIC);
                    break; }
                case QMetaType::Int:
                case QMetaType::Bool:
                    res = sqlite3_bind_int(d->stmt, i + 1, value.toInt());
                    break;
                case QMetaType::Double:
                    res = sqlite3_bind_double(d->stmt, i + 1, value.toDouble());
                    break;
                case QMetaType::UInt:
                case QMetaType::LongLong:
                    res = sqlite3_bind_int64(d->stmt, i + 1, value.toLongLong());
                    break;
                case QMetaType::QDateTime: {
                    const QDateTime dateTime = value.toDateTime();
                    const QString str = dateTime.toString(Qt::ISODateWithMs);
                    res = sqlite3_bind_text16(d->stmt, i + 1, str.data(),
                                              int(str.size() * sizeof(ushort)),
                                              SQLITE_TRANSIENT);
                    break;
                }
                case QMetaType::QTime: {
                    const QTime time = value.toTime();
                    const QString str = time.toString(u"hh:mm:ss.zzz");
                    res = sqlite3_bind_text16(d->stmt, i + 1, str.data(),
                                              int(str.size() * sizeof(ushort)),
                                              SQLITE_TRANSIENT);
                    break;
                }
                case QMetaType::QString: {
                    // lifetime of string == lifetime of its qvariant
                    const QString *str = static_cast<const QString*>(value.constData());
                    res = sqlite3_bind_text16(d->stmt, i + 1, str->unicode(),
                                              int(str->size()) * sizeof(QChar),
                                              SQLITE_STATIC);
                    break; }
                default: {
                    const QString str = value.toString();
                    // SQLITE_TRANSIENT makes sure that sqlite buffers the data
                    res = sqlite3_bind_text16(d->stmt, i + 1, str.data(),
                                              int(str.size()) * sizeof(QChar),
                                              SQLITE_TRANSIENT);
                    break; }
                }
            }
            if (res != SQLITE_OK) {
                setLastError(qMakeError(d->drv_d_func()->access, QCoreApplication::translate("QSQLiteResult",
                             "Unable to bind parameters"), QSqlError::StatementError, res));
                d->finalize();
                return false;
            }
        }
    } else {
        setLastError(QSqlError(QCoreApplication::translate("QSQLiteResult",
                        "Parameter count mismatch"), QString(), QSqlError::StatementError));
        return false;
    }
    d->skippedStatus = d->fetchNext(d->firstRow, 0, true);
    if (lastError().isValid()) {
        setSelect(false);
        setActive(false);
        return false;
    }
    setSelect(!d->rInf.isEmpty());
    setActive(true);
    return true;
}
 
bool QSQLiteResult::gotoNext(QSqlCachedResult::ValueCache& row, int idx)
{
    Q_D(QSQLiteResult);
    return d->fetchNext(row, idx, false);
}
 
int QSQLiteResult::size()
{
    return -1;
}
 
int QSQLiteResult::numRowsAffected()
{
    Q_D(const QSQLiteResult);
    return sqlite3_changes(d->drv_d_func()->access);
}
 
QVariant QSQLiteResult::lastInsertId() const
{
    Q_D(const QSQLiteResult);
    if (isActive()) {
        qint64 id = sqlite3_last_insert_rowid(d->drv_d_func()->access);
        if (id)
            return id;
    }
    return QVariant();
}
 
QSqlRecord QSQLiteResult::record() const
{
    Q_D(const QSQLiteResult);
    if (!isActive() || !isSelect())
        return QSqlRecord();
    return d->rInf;
}
 
void QSQLiteResult::detachFromResultSet()
{
    Q_D(QSQLiteResult);
    if (d->stmt)
        sqlite3_reset(d->stmt);
}
 
QVariant QSQLiteResult::handle() const
{
    Q_D(const QSQLiteResult);
    return QVariant::fromValue(d->stmt);
}
 
/////////////////////////////////////////////////////////
 
#if QT_CONFIG(regularexpression)
static void _q_regexp(sqlite3_context* context, int argc, sqlite3_value** argv)
{
    if (Q_UNLIKELY(argc != 2)) {
        sqlite3_result_int(context, 0);
        return;
    }
 
    const QString pattern = QString::fromUtf8(
        reinterpret_cast<const char*>(sqlite3_value_text(argv[0])));
    const QString subject = QString::fromUtf8(
        reinterpret_cast<const char*>(sqlite3_value_text(argv[1])));
 
    auto cache = static_cast<QCache<QString, QRegularExpression>*>(sqlite3_user_data(context));
    auto regexp = cache->object(pattern);
    const bool wasCached = regexp;
 
    if (!wasCached)
        regexp = new QRegularExpression(pattern, QRegularExpression::DontCaptureOption);
 
    const bool found = subject.contains(*regexp);
 
    if (!wasCached)
        cache->insert(pattern, regexp);
 
    sqlite3_result_int(context, int(found));
}
 
static void _q_regexp_cleanup(void *cache)
{
    delete static_cast<QCache<QString, QRegularExpression>*>(cache);
}
#endif
 
static void _q_lower(sqlite3_context* context, int argc, sqlite3_value** argv)
{
    if (Q_UNLIKELY(argc != 1)) {
        sqlite3_result_text(context, nullptr, 0, nullptr);
        return;
    }
    const QString lower = QString::fromUtf8(
        reinterpret_cast<const char*>(sqlite3_value_text(argv[0]))).toLower();
    const QByteArray ba = lower.toUtf8();
    sqlite3_result_text(context, ba.data(), ba.size(), SQLITE_TRANSIENT);
}
 
static void _q_upper(sqlite3_context* context, int argc, sqlite3_value** argv)
{
    if (Q_UNLIKELY(argc != 1)) {
        sqlite3_result_text(context, nullptr, 0, nullptr);
        return;
    }
    const QString upper = QString::fromUtf8(
        reinterpret_cast<const char*>(sqlite3_value_text(argv[0]))).toUpper();
    const QByteArray ba = upper.toUtf8();
    sqlite3_result_text(context, ba.data(), ba.size(), SQLITE_TRANSIENT);
}
 
QSQLiteDriver::QSQLiteDriver(QObject * parent)
    : QSqlDriver(*new QSQLiteDriverPrivate, parent)
{
}
 
QSQLiteDriver::QSQLiteDriver(sqlite3 *connection, QObject *parent)
    : QSqlDriver(*new QSQLiteDriverPrivate, parent)
{
    Q_D(QSQLiteDriver);
    d->access = connection;
    setOpen(true);
    setOpenError(false);
}
 
 
QSQLiteDriver::~QSQLiteDriver()
{
    close();
}
 
bool QSQLiteDriver::hasFeature(DriverFeature f) const
{
    switch (f) {
    case BLOB:
    case Transactions:
    case Unicode:
    case LastInsertId:
    case PreparedQueries:
    case PositionalPlaceholders:
    case SimpleLocking:
    case FinishQuery:
    case LowPrecisionNumbers:
    case EventNotifications:
        return true;
    case QuerySize:
    case BatchOperations:
    case MultipleResultSets:
    case CancelQuery:
        return false;
    case NamedPlaceholders:
#if (SQLITE_VERSION_NUMBER < 3003011)
        return false;
#else
        return true;
#endif
 
    }
    return false;
}
 
/*
   SQLite dbs have no user name, passwords, hosts or ports.
   just file names.
*/
bool QSQLiteDriver::open(const QString & db, const QString &, const QString &, const QString &, int, const QString &conOpts)
{
    Q_D(QSQLiteDriver);
    if (isOpen())
        close();
 
 
    int timeOut = 5000;
    bool sharedCache = false;
    bool openReadOnlyOption = false;
    bool openUriOption = false;
    bool useExtendedResultCodes = true;
    bool useQtVfs = false;
    bool useQtCaseFolding = false;
    bool openNoFollow = false;
#if QT_CONFIG(regularexpression)
    static const auto regexpConnectOption = "QSQLITE_ENABLE_REGEXP"_L1;
    bool defineRegexp = false;
    int regexpCacheSize = 25;
#endif
 
    const auto opts = QStringView{conOpts}.split(u';', Qt::SkipEmptyParts);
    for (auto option : opts) {
        option = option.trimmed();
        if (option.startsWith("QSQLITE_BUSY_TIMEOUT"_L1)) {
            option = option.mid(20).trimmed();
            if (option.startsWith(u'=')) {
                bool ok;
                const int nt = option.mid(1).trimmed().toInt(&ok);
                if (ok)
                    timeOut = nt;
            }
        } else if (option == "QSQLITE_USE_QT_VFS"_L1) {
            useQtVfs = true;
        } else if (option == "QSQLITE_OPEN_READONLY"_L1) {
            openReadOnlyOption = true;
        } else if (option == "QSQLITE_OPEN_URI"_L1) {
            openUriOption = true;
        } else if (option == "QSQLITE_ENABLE_SHARED_CACHE"_L1) {
            sharedCache = true;
        } else if (option == "QSQLITE_NO_USE_EXTENDED_RESULT_CODES"_L1) {
            useExtendedResultCodes = false;
        } else if (option == "QSQLITE_ENABLE_NON_ASCII_CASE_FOLDING"_L1) {
            useQtCaseFolding = true;
        } else if (option == "QSQLITE_OPEN_NOFOLLOW"_L1) {
            openNoFollow = true;
        }
#if QT_CONFIG(regularexpression)
        else if (option.startsWith(regexpConnectOption)) {
            option = option.mid(regexpConnectOption.size()).trimmed();
            if (option.isEmpty()) {
                defineRegexp = true;
            } else if (option.startsWith(u'=')) {
                bool ok = false;
                const int cacheSize = option.mid(1).trimmed().toInt(&ok);
                if (ok) {
                    defineRegexp = true;
                    if (cacheSize > 0)
                        regexpCacheSize = cacheSize;
                }
            }
        }
#endif
        else
            qCWarning(lcSqlite, "Unsupported option '%ls'", qUtf16Printable(option.toString()));
    }
 
    int openMode = (openReadOnlyOption ? SQLITE_OPEN_READONLY : (SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE));
    openMode |= (sharedCache ? SQLITE_OPEN_SHAREDCACHE : SQLITE_OPEN_PRIVATECACHE);
    if (openUriOption)
        openMode |= SQLITE_OPEN_URI;
    if (openNoFollow) {
#if defined(SQLITE_OPEN_NOFOLLOW)
        openMode |= SQLITE_OPEN_NOFOLLOW;
#else
        qCWarning(lcSqlite, "SQLITE_OPEN_NOFOLLOW not supported with the SQLite version %s", sqlite3_libversion());
#endif
    }
 
    openMode |= SQLITE_OPEN_NOMUTEX;
 
    const int res = sqlite3_open_v2(db.toUtf8().constData(), &d->access, openMode, useQtVfs ? "QtVFS" : nullptr);
 
    if (res == SQLITE_OK) {
        sqlite3_busy_timeout(d->access, timeOut);
        sqlite3_extended_result_codes(d->access, useExtendedResultCodes);
        setOpen(true);
        setOpenError(false);
#if QT_CONFIG(regularexpression)
        if (defineRegexp) {
            auto cache = new QCache<QString, QRegularExpression>(regexpCacheSize);
            sqlite3_create_function_v2(d->access, "regexp", 2, SQLITE_UTF8, cache,
                                       &_q_regexp, nullptr,
                                       nullptr, &_q_regexp_cleanup);
        }
#endif
        if (useQtCaseFolding) {
            sqlite3_create_function_v2(d->access, "lower", 1, SQLITE_UTF8, nullptr,
                                       &_q_lower, nullptr, nullptr, nullptr);
            sqlite3_create_function_v2(d->access, "upper", 1, SQLITE_UTF8, nullptr,
                                       &_q_upper, nullptr, nullptr, nullptr);
        }
        return true;
    } else {
        setLastError(qMakeError(d->access, tr("Error opening database"),
                     QSqlError::ConnectionError, res));
        setOpenError(true);
 
        if (d->access) {
            sqlite3_close(d->access);
            d->access = nullptr;
        }
 
        return false;
    }
}
 
void QSQLiteDriver::close()
{
    Q_D(QSQLiteDriver);
    if (isOpen()) {
        for (QSQLiteResult *result : std::as_const(d->results))
            result->d_func()->finalize();
 
        if (d->access && (d->notificationid.size() > 0)) {
            d->notificationid.clear();
            sqlite3_update_hook(d->access, nullptr, nullptr);
        }
 
        const int res = sqlite3_close(d->access);
 
        if (res != SQLITE_OK)
            setLastError(qMakeError(d->access, tr("Error closing database"), QSqlError::ConnectionError, res));
        d->access = nullptr;
        setOpen(false);
        setOpenError(false);
    }
}
 
QSqlResult *QSQLiteDriver::createResult() const
{
    return new QSQLiteResult(this);
}
 
bool QSQLiteDriver::beginTransaction()
{
    if (!isOpen() || isOpenError())
        return false;
 
    QSqlQuery q(createResult());
    if (!q.exec("BEGIN"_L1)) {
        setLastError(QSqlError(tr("Unable to begin transaction"),
                               q.lastError().databaseText(), QSqlError::TransactionError));
        return false;
    }
 
    return true;
}
 
bool QSQLiteDriver::commitTransaction()
{
    if (!isOpen() || isOpenError())
        return false;
 
    QSqlQuery q(createResult());
    if (!q.exec("COMMIT"_L1)) {
        setLastError(QSqlError(tr("Unable to commit transaction"),
                               q.lastError().databaseText(), QSqlError::TransactionError));
        return false;
    }
 
    return true;
}
 
bool QSQLiteDriver::rollbackTransaction()
{
    if (!isOpen() || isOpenError())
        return false;
 
    QSqlQuery q(createResult());
    if (!q.exec("ROLLBACK"_L1)) {
        setLastError(QSqlError(tr("Unable to rollback transaction"),
                               q.lastError().databaseText(), QSqlError::TransactionError));
        return false;
    }
 
    return true;
}
 
QStringList QSQLiteDriver::tables(QSql::TableType type) const
{
    QStringList res;
    if (!isOpen())
        return res;
 
    QSqlQuery q(createResult());
    q.setForwardOnly(true);
 
    QString sql = "SELECT name FROM sqlite_master WHERE %1 "
                  "UNION ALL SELECT name FROM sqlite_temp_master WHERE %1"_L1;
    if ((type & QSql::Tables) && (type & QSql::Views))
        sql = sql.arg("type='table' OR type='view'"_L1);
    else if (type & QSql::Tables)
        sql = sql.arg("type='table'"_L1);
    else if (type & QSql::Views)
        sql = sql.arg("type='view'"_L1);
    else
        sql.clear();
 
    if (!sql.isEmpty() && q.exec(sql)) {
        while(q.next())
            res.append(q.value(0).toString());
    }
 
    if (type & QSql::SystemTables) {
        // there are no internal tables beside this one:
        res.append("sqlite_master"_L1);
    }
 
    return res;
}
 
QSqlIndex QSQLiteDriver::primaryIndex(const QString &tablename) const
{
    Q_D(const QSQLiteDriver);
    if (!isOpen())
        return QSqlIndex();
 
    QSqlQuery q(createResult());
    q.setForwardOnly(true);
    return d->getTableInfo(q, tablename, true);
}
 
QSqlRecord QSQLiteDriver::record(const QString &tablename) const
{
    Q_D(const QSQLiteDriver);
    if (!isOpen())
        return QSqlRecord();
 
    QSqlQuery q(createResult());
    q.setForwardOnly(true);
    return d->getTableInfo(q, tablename);
}
 
QVariant QSQLiteDriver::handle() const
{
    Q_D(const QSQLiteDriver);
    return QVariant::fromValue(d->access);
}
 
QString QSQLiteDriver::escapeIdentifier(const QString &identifier, IdentifierType type) const
{
    Q_D(const QSQLiteDriver);
    if (identifier.isEmpty() || isIdentifierEscaped(identifier, type))
        return identifier;
 
    const auto indexOfSeparator = identifier.indexOf(u'.');
    if (indexOfSeparator > -1) {
        auto leftName = QStringView{identifier}.first(indexOfSeparator);
        auto rightName = QStringView{identifier}.sliced(indexOfSeparator + 1);
        const QStringView leftEnclose = d->isIdentifierEscaped(leftName) ? u"" : u"\"";
        const QStringView rightEnclose = d->isIdentifierEscaped(rightName) ? u"" : u"\"";
        if (leftEnclose.isEmpty() || rightEnclose.isEmpty())
            return (leftEnclose + leftName + leftEnclose + u'.' + rightEnclose + rightName
                    + rightEnclose);
    }
    return u'"' + identifier + u'"';
}
 
bool QSQLiteDriver::isIdentifierEscaped(const QString &identifier, IdentifierType type) const
{
    Q_D(const QSQLiteDriver);
    Q_UNUSED(type);
    return d->isIdentifierEscaped(QStringView{identifier});
}
 
QString QSQLiteDriver::stripDelimiters(const QString &identifier, IdentifierType type) const
{
    Q_D(const QSQLiteDriver);
    const auto indexOfSeparator = identifier.indexOf(u'.');
    if (indexOfSeparator > -1) {
        auto leftName = QStringView{identifier}.first(indexOfSeparator);
        auto rightName = QStringView{identifier}.sliced(indexOfSeparator + 1);
        const auto leftEscaped = d->isIdentifierEscaped(leftName);
        const auto rightEscaped = d->isIdentifierEscaped(rightName);
        if (leftEscaped || rightEscaped) {
            if (leftEscaped)
                leftName = leftName.sliced(1).chopped(1);
            if (rightEscaped)
                rightName = rightName.sliced(1).chopped(1);
            return leftName + u'.' + rightName;
        }
    }
 
    if (isIdentifierEscaped(identifier, type))
        return identifier.mid(1, identifier.size() - 2);
 
    return identifier;
}
 
static void handle_sqlite_callback(void *qobj,int aoperation, char const *adbname, char const *atablename,
                                   sqlite3_int64 arowid)
{
    Q_UNUSED(aoperation);
    Q_UNUSED(adbname);
    QSQLiteDriver *driver = static_cast<QSQLiteDriver *>(qobj);
    if (driver) {
        QMetaObject::invokeMethod(driver, "handleNotification", Qt::QueuedConnection,
                                  Q_ARG(QString, QString::fromUtf8(atablename)), Q_ARG(qint64, arowid));
    }
}
 
bool QSQLiteDriver::subscribeToNotification(const QString &name)
{
    Q_D(QSQLiteDriver);
    if (!isOpen()) {
        qCWarning(lcSqlite, "QSQLiteDriver::subscribeToNotification: Database not open.");
        return false;
    }
 
    if (d->notificationid.contains(name)) {
        qCWarning(lcSqlite, "QSQLiteDriver::subscribeToNotification: Already subscribing to '%ls'.",
                  qUtf16Printable(name));
        return false;
    }
 
    //sqlite supports only one notification callback, so only the first is registered
    d->notificationid << name;
    if (d->notificationid.size() == 1)
        sqlite3_update_hook(d->access, &handle_sqlite_callback, reinterpret_cast<void *> (this));
 
    return true;
}
 
bool QSQLiteDriver::unsubscribeFromNotification(const QString &name)
{
    Q_D(QSQLiteDriver);
    if (!isOpen()) {
        qCWarning(lcSqlite, "QSQLiteDriver::unsubscribeFromNotification: Database not open.");
        return false;
    }
 
    if (!d->notificationid.contains(name)) {
        qCWarning(lcSqlite, "QSQLiteDriver::unsubscribeFromNotification: Not subscribed to '%ls'.",
                  qUtf16Printable(name));
        return false;
    }
 
    d->notificationid.removeAll(name);
    if (d->notificationid.isEmpty())
        sqlite3_update_hook(d->access, nullptr, nullptr);
 
    return true;
}
 
QStringList QSQLiteDriver::subscribedToNotifications() const
{
    Q_D(const QSQLiteDriver);
    return d->notificationid;
}
 
void QSQLiteDriver::handleNotification(const QString &tableName, qint64 rowid)
{
    Q_D(const QSQLiteDriver);
    if (d->notificationid.contains(tableName))
        emit notification(tableName, QSqlDriver::UnknownSource, QVariant(rowid));
}
 
QT_END_NAMESPACE
 
#include "moc_qsql_sqlite_p.cpp"