qsqlresult.cpp

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#include "qvariant.h"
#include "qhash.h"
#include "qregexp.h"
#include "qsqlerror.h"
#include "qsqlfield.h"
#include "qsqlrecord.h"
#include "qsqlresult.h"
#include "qvector.h"
#include "qsqldriver.h"
#include "qpointer.h"
#include <QDebug>

QT_BEGIN_NAMESPACE

struct QHolder {
    QHolder(const QString& hldr = QString(), int index = -1): holderName(hldr), holderPos(index) {}
    bool operator==(const QHolder& h) const { return h.holderPos == holderPos && h.holderName == holderName; }
    bool operator!=(const QHolder& h) const { return h.holderPos != holderPos || h.holderName != holderName; }
    QString holderName;
    int holderPos;
};

class QSqlResultPrivate
{
public:
    QSqlResultPrivate(QSqlResult* d)
    : q(d), idx(QSql::BeforeFirstRow), active(false),
      isSel(false), forwardOnly(false), precisionPolicy(QSql::LowPrecisionDouble), bindCount(0), binds(QSqlResult::PositionalBinding)
    {}

    void clearValues()
    {
        values.clear();
        bindCount = 0;
    }

    void resetBindCount()
    {
        bindCount = 0;
    }

    void clearIndex()
    {
        indexes.clear();
        holders.clear();
        types.clear();
    }

    void clear()
    {
        clearValues();
        clearIndex();;
    }

    QString positionalToNamedBinding();
    QString namedToPositionalBinding();
    QString holderAt(int index) const;

public:
    QSqlResult* q;
    QPointer<QSqlDriver> sqldriver;
    int idx;
    QString sql;
    bool active;
    bool isSel;
    QSqlError error;
    bool forwardOnly;
    QSql::NumericalPrecisionPolicy precisionPolicy;

    int bindCount;
    QSqlResult::BindingSyntax binds;

    QString executedQuery;
    QHash<int, QSql::ParamType> types;
    QVector<QVariant> values;
    typedef QHash<QString, int> IndexMap;
    IndexMap indexes;

    typedef QVector<QHolder> QHolderVector;
    QHolderVector holders;
};

QString QSqlResultPrivate::holderAt(int index) const
{
    return indexes.key(index);
}

// return a unique id for bound names
static QString qFieldSerial(int i)
{
    ushort arr[] = { ':', 'f', 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
    ushort *ptr = &arr[1];

    while (i > 0) {
        *(++ptr) = 'a' + i % 16;
        i >>= 4;
    }

    return QString(reinterpret_cast<const QChar *>(arr), int(ptr - arr) + 1);
}

static bool qIsAlnum(QChar ch)
{
    uint u = uint(ch.unicode());
    // matches [a-zA-Z0-9_]
    return u - 'a' < 26 || u - 'A' < 26 || u - '0' < 10 || u == '_';
}

QString QSqlResultPrivate::positionalToNamedBinding()
{
    int n = sql.size();

    QString result;
    result.reserve(n * 5 / 4);
    bool inQuote = false;
    int count = 0;

    for (int i = 0; i < n; ++i) {
        QChar ch = sql.at(i);
        if (ch == QLatin1Char('?') && !inQuote) {
            result += qFieldSerial(count++);
        } else {
            if (ch == QLatin1Char('\''))
                inQuote = !inQuote;
            result += ch;
        }
    }
    result.squeeze();
    return result;
}

QString QSqlResultPrivate::namedToPositionalBinding()
{
    int n = sql.size();

    QString result;
    result.reserve(n);
    bool inQuote = false;
    int count = 0;
    int i = 0;

    while (i < n) {
        QChar ch = sql.at(i);
        if (ch == QLatin1Char(':') && !inQuote
                && (i == 0 || sql.at(i - 1) != QLatin1Char(':'))
                && (i + 1 < n && qIsAlnum(sql.at(i + 1)))) {
            int pos = i + 2;
            while (pos < n && qIsAlnum(sql.at(pos)))
                ++pos;
            indexes[sql.mid(i, pos - i)] = count++;
            result += QLatin1Char('?');
            i = pos;
        } else {
            if (ch == QLatin1Char('\''))
                inQuote = !inQuote;
            result += ch;
            ++i;
        }
    }
    result.squeeze();
    return result;
}

QSqlResult::QSqlResult(const QSqlDriver *db)
{
    d = new QSqlResultPrivate(this);
    d->sqldriver = const_cast<QSqlDriver *>(db);
    if(db) {
        setNumericalPrecisionPolicy(db->numericalPrecisionPolicy());
    }
}

QSqlResult::~QSqlResult()
{
    delete d;
}

void QSqlResult::setQuery(const QString& query)
{
    d->sql = query;
}

QString QSqlResult::lastQuery() const
{
    return d->sql;
}

int QSqlResult::at() const
{
    return d->idx;
}


bool QSqlResult::isValid() const
{
    return d->idx != QSql::BeforeFirstRow && d->idx != QSql::AfterLastRow;
}

bool QSqlResult::isActive() const
{
    return d->active;
}

void QSqlResult::setAt(int index)
{
    d->idx = index;
}


void QSqlResult::setSelect(bool select)
{
    d->isSel = select;
}

bool QSqlResult::isSelect() const
{
    return d->isSel;
}

const QSqlDriver *QSqlResult::driver() const
{
    return d->sqldriver;
}


void QSqlResult::setActive(bool active)
{
    if (active && d->executedQuery.isEmpty())
        d->executedQuery = d->sql;

    d->active = active;
}

void QSqlResult::setLastError(const QSqlError &error)
{
    d->error = error;
}


QSqlError QSqlResult::lastError() const
{
    return d->error;
}

bool QSqlResult::fetchNext()
{
    return fetch(at() + 1);
}

bool QSqlResult::fetchPrevious()
{
    return fetch(at() - 1);
}

bool QSqlResult::isForwardOnly() const
{
    return d->forwardOnly;
}

void QSqlResult::setForwardOnly(bool forward)
{
    d->forwardOnly = forward;
}

bool QSqlResult::savePrepare(const QString& query)
{
    if (!driver())
        return false;
    d->clear();
    d->sql = query;
    if (!driver()->hasFeature(QSqlDriver::PreparedQueries))
        return prepare(query);

    if (driver()->hasFeature(QSqlDriver::NamedPlaceholders)) {
        // parse the query to memorize parameter location
        d->namedToPositionalBinding();
        d->executedQuery = d->positionalToNamedBinding();
    } else {
        d->executedQuery = d->namedToPositionalBinding();
    }
    return prepare(d->executedQuery);
}

bool QSqlResult::prepare(const QString& query)
{
    int n = query.size();

    bool inQuote = false;
    int i = 0;

    while (i < n) {
        QChar ch = query.at(i);
        if (ch == QLatin1Char(':') && !inQuote
                && (i == 0 || query.at(i - 1) != QLatin1Char(':'))
                && (i + 1 < n && qIsAlnum(query.at(i + 1)))) {
            int pos = i + 2;
            while (pos < n && qIsAlnum(query.at(pos)))
                ++pos;

            d->holders.append(QHolder(query.mid(i, pos - i), i));
            i = pos;
        } else {
            if (ch == QLatin1Char('\''))
                inQuote = !inQuote;
            ++i;
        }
    }
    d->sql = query;
    return true; // fake prepares should always succeed
}

bool QSqlResult::exec()
{
    bool ret;
    // fake preparation - just replace the placeholders..
    QString query = lastQuery();
    if (d->binds == NamedBinding) {
        int i;
        QVariant val;
        QString holder;
        for (i = d->holders.count() - 1; i >= 0; --i) {
            holder = d->holders.at(i).holderName;
            val = d->values.value(d->indexes.value(holder));
            QSqlField f(QLatin1String(""), val.type());
            f.setValue(val);
            query = query.replace(d->holders.at(i).holderPos,
                                   holder.length(), driver()->formatValue(f));
        }
    } else {
        QString val;
        int i = 0;
        int idx = 0;
        for (idx = 0; idx < d->values.count(); ++idx) {
            i = query.indexOf(QLatin1Char('?'), i);
            if (i == -1)
                continue;
            QVariant var = d->values.value(idx);
            QSqlField f(QLatin1String(""), var.type());
            if (var.isNull())
                f.clear();
            else
                f.setValue(var);
            val = driver()->formatValue(f);
            query = query.replace(i, 1, driver()->formatValue(f));
            i += val.length();
        }
    }

    // have to retain the original query with placeholders
    QString orig = lastQuery();
    ret = reset(query);
    d->executedQuery = query;
    setQuery(orig);
    d->resetBindCount();
    return ret;
}

void QSqlResult::bindValue(int index, const QVariant& val, QSql::ParamType paramType)
{
    d->binds = PositionalBinding;
    d->indexes[qFieldSerial(index)] = index;
    if (d->values.count() <= index)
        d->values.resize(index + 1);
    d->values[index] = val;
    if (paramType != QSql::In || !d->types.isEmpty())
        d->types[index] = paramType;
}

void QSqlResult::bindValue(const QString& placeholder, const QVariant& val,
                           QSql::ParamType paramType)
{
    d->binds = NamedBinding;
    // if the index has already been set when doing emulated named
    // bindings - don't reset it
    int idx = d->indexes.value(placeholder, -1);
    if (idx >= 0) {
        if (d->values.count() <= idx)
            d->values.resize(idx + 1);
        d->values[idx] = val;
    } else {
        d->values.append(val);
        idx = d->values.count() - 1;
        d->indexes[placeholder] = idx;
    }

    if (paramType != QSql::In || !d->types.isEmpty())
        d->types[idx] = paramType;
}

void QSqlResult::addBindValue(const QVariant& val, QSql::ParamType paramType)
{
    d->binds = PositionalBinding;
    bindValue(d->bindCount, val, paramType);
    ++d->bindCount;
}

QVariant QSqlResult::boundValue(int index) const
{
    return d->values.value(index);
}

QVariant QSqlResult::boundValue(const QString& placeholder) const
{
    int idx = d->indexes.value(placeholder, -1);
    return d->values.value(idx);
}

QSql::ParamType QSqlResult::bindValueType(int index) const
{
    return d->types.value(index, QSql::In);
}

QSql::ParamType QSqlResult::bindValueType(const QString& placeholder) const
{
    return d->types.value(d->indexes.value(placeholder, -1), QSql::In);
}

int QSqlResult::boundValueCount() const
{
    return d->values.count();
}

QVector<QVariant>& QSqlResult::boundValues() const
{
    return d->values;
}

QSqlResult::BindingSyntax QSqlResult::bindingSyntax() const
{
    return d->binds;
}

void QSqlResult::clear()
{
    d->clear();
}

QString QSqlResult::executedQuery() const
{
    return d->executedQuery;
}

void QSqlResult::resetBindCount()
{
    d->resetBindCount();
}

QString QSqlResult::boundValueName(int index) const
{
    return d->holderAt(index);
}

bool QSqlResult::hasOutValues() const
{
    if (d->types.isEmpty())
        return false;
    QHash<int, QSql::ParamType>::ConstIterator it;
    for (it = d->types.constBegin(); it != d->types.constEnd(); ++it) {
        if (it.value() != QSql::In)
            return true;
    }
    return false;
}

QSqlRecord QSqlResult::record() const
{
    return QSqlRecord();
}

QVariant QSqlResult::lastInsertId() const
{
    return QVariant();
}

void QSqlResult::virtual_hook(int, void *)
{
}

bool QSqlResult::execBatch(bool arrayBind)
{
    if (driver()->hasFeature(QSqlDriver::BatchOperations)) {
        virtual_hook(BatchOperation, &arrayBind);
        d->resetBindCount();
        return d->error.type() == QSqlError::NoError;
    } else {
        QVector<QVariant> values = d->values;
        if (values.count() == 0)
            return false;
        for (int i = 0; i < values.at(0).toList().count(); ++i) {
            for (int j = 0; j < values.count(); ++j)
                bindValue(j, values.at(j).toList().at(i), QSql::In);
            if (!exec())
                return false;
        }
        return true;
    }
    return false;
}

void QSqlResult::detachFromResultSet()
{
    if (driver()->hasFeature(QSqlDriver::FinishQuery) 
            || driver()->hasFeature(QSqlDriver::SimpleLocking))
        virtual_hook(DetachFromResultSet, 0);
}

void QSqlResult::setNumericalPrecisionPolicy(QSql::NumericalPrecisionPolicy policy)
{
    d->precisionPolicy = policy;
    virtual_hook(SetNumericalPrecision, &policy);
}

QSql::NumericalPrecisionPolicy QSqlResult::numericalPrecisionPolicy() const
{
    return d->precisionPolicy;
}

bool QSqlResult::nextResult()
{
    if (driver()->hasFeature(QSqlDriver::MultipleResultSets)) {
        bool result = false;
        virtual_hook(NextResult, &result);
        return result;
    }
    return false;
}

QVariant QSqlResult::handle() const
{
    return QVariant();
}

QT_END_NAMESPACE