sqlite/sqliteconnection.cpp

/* This file is part of the KDE project
   Copyright (C) 2003-2006 Jaroslaw Staniek <js@iidea.pl>
 
   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public
   License as published by the Free Software Foundation; either
   version 2 of the License, or (at your option) any later version.
 
   This program 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
   Library General Public License for more details.
 
   You should have received a copy of the GNU Library General Public License
   along with this program; see the file COPYING.  If not, write to
   the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
*/
 
#include "sqliteconnection.h"
#include "sqliteconnection_p.h"
#include "sqlitecursor.h"
#include "sqlitepreparedstatement.h"
 
#include "sqlite.h"
 
#ifndef SQLITE2
# include "kexisql.h" //for isReadOnly()
#endif
 
#include <kexidb/driver.h>
#include <kexidb/cursor.h>
#include <kexidb/error.h>
#include <kexiutils/utils.h>
 
#include <tqfile.h>
#include <tqdir.h>
#include <tqregexp.h>
 
#include <kgenericfactory.h>
#include <kdebug.h>
 
//remove debug
#undef KexiDBDrvDbg
#define KexiDBDrvDbg if (0) kdDebug()
 
using namespace KexiDB;
 
SQLiteConnectionInternal::SQLiteConnectionInternal(Connection *connection)
 : ConnectionInternal(connection)
 , data(0)
 , data_owned(true)
 , errmsg_p(0)
 , res(SQLITE_OK)
 , temp_st(0x10000)
#ifdef SQLITE3
 , result_name(0)
#endif
{
}
 
SQLiteConnectionInternal::~SQLiteConnectionInternal() 
{
    if (data_owned && data) {
        free( data ); 
        data = 0;
    }
//sqlite_freemem does this  if (errmsg) {
//      free( errmsg );
//      errmsg = 0;
//  }
}
 
void SQLiteConnectionInternal::storeResult()
{
    if (errmsg_p) {
        errmsg = errmsg_p;
        sqlite_free(errmsg_p);
        errmsg_p = 0;
    }
#ifdef SQLITE3
    errmsg = (data && res!=SQLITE_OK) ? sqlite3_errmsg(data) : 0;
#endif
}

SQLiteConnection::SQLiteConnection( Driver *driver, ConnectionData &conn_data )
    : Connection( driver, conn_data )
    ,d(new SQLiteConnectionInternal(this))
{
}
 
SQLiteConnection::~SQLiteConnection()
{
    KexiDBDrvDbg << "SQLiteConnection::~SQLiteConnection()" << endl;
    //disconnect if was connected
//  disconnect();
    destroy();
    delete d;
    KexiDBDrvDbg << "SQLiteConnection::~SQLiteConnection() ok" << endl;
}
 
bool SQLiteConnection::drv_connect(KexiDB::ServerVersionInfo& version)
{
    KexiDBDrvDbg << "SQLiteConnection::connect()" << endl;
    version.string = TQString(SQLITE_VERSION); //defined in sqlite3.h
    TQRegExp re("(\\d+)\\.(\\d+)\\.(\\d+)");
    if (re.exactMatch(version.string)) {
        version.major = re.cap(1).toUInt();
        version.minor = re.cap(2).toUInt();
        version.release = re.cap(3).toUInt();
    }
    return true;
}
 
bool SQLiteConnection::drv_disconnect()
{
    KexiDBDrvDbg << "SQLiteConnection::disconnect()" << endl;
    return true;
}
 
bool SQLiteConnection::drv_getDatabasesList( TQStringList &list )
{
    //this is one-db-per-file database
    list.append( data()->fileName() ); //more consistent than dbFileName() ?
    return true;
}
 
bool SQLiteConnection::drv_containsTable( const TQString &tableName )
{
    bool success;
    return resultExists(TQString("select name from sqlite_master where type='table' and name LIKE %1")
        .arg(driver()->escapeString(tableName)), success) && success;
}
 
bool SQLiteConnection::drv_getTablesList( TQStringList &list )
{
    KexiDB::Cursor *cursor;
    m_sql = "select lower(name) from sqlite_master where type='table'";
    if (!(cursor = executeQuery( m_sql ))) {
        KexiDBWarn << "Connection::drv_getTablesList(): !executeQuery()" << endl;
        return false;
    }
    list.clear();
    cursor->moveFirst();
    while (!cursor->eof() && !cursor->error()) {
        list += cursor->value(0).toString();
        cursor->moveNext();
    }
    if (cursor->error()) {
        deleteCursor(cursor);
        return false;
    }
    return deleteCursor(cursor);
}
 
bool SQLiteConnection::drv_createDatabase( const TQString &dbName )
{
    // SQLite creates a new db is it does not exist
    return drv_useDatabase(dbName);
#if 0
    d->data = sqlite_open( TQFile::encodeName( data()->fileName() ), 0/*mode: unused*/, 
        &d->errmsg_p );
    d->storeResult();
    return d->data != 0;
#endif
}
 
bool SQLiteConnection::drv_useDatabase( const TQString &dbName, bool *cancelled, 
    MessageHandler* msgHandler )
{
    Q_UNUSED(dbName);
//  KexiDBDrvDbg << "drv_useDatabase(): " << data()->fileName() << endl;
#ifdef SQLITE2
    Q_UNUSED(cancelled);
    Q_UNUSED(msgHandler);
    d->data = sqlite_open( TQFile::encodeName( data()->fileName() ), 0/*mode: unused*/, 
        &d->errmsg_p );
    d->storeResult();
    return d->data != 0;
#else //SQLITE3
    //TODO: perhaps allow to use sqlite3_open16() as well for SQLite ~ 3.3 ?
    int exclusiveFlag = Connection::isReadOnly() ? SQLITE_OPEN_READONLY : SQLITE_OPEN_WRITE_LOCKED; // <-- shared read + (if !r/o): exclusive write
    int allowReadonly = 1;
    const bool wasReadOnly = Connection::isReadOnly();
 
    d->res = sqlite3_open( 
        //TQFile::encodeName( data()->fileName() ), 
        data()->fileName().utf8(), /* unicode expected since SQLite 3.1 */
        &d->data,
        exclusiveFlag,
        allowReadonly /* If 1 and locking fails, try opening in read-only mode */
    );
    d->storeResult();
 
    if (d->res == SQLITE_OK && cancelled && !wasReadOnly && allowReadonly && isReadOnly()) {
        //opened as read only, ask
        if (KMessageBox::Continue != 
            askQuestion( 
            i18n("Do you want to open file \"%1\" as read-only?")
                .arg(TQDir::convertSeparators(data()->fileName()))
            + "\n\n"
            + i18n("The file is probably already open on this or another computer.") + " "
            + i18n("Could not gain exclusive access for writing the file."),
            KMessageBox::WarningContinueCancel, KMessageBox::Continue, 
            KGuiItem(i18n("Open As Read-Only"), "document-open"), KStdGuiItem::cancel(),
            "askBeforeOpeningFileReadOnly", KMessageBox::Notify, msgHandler ))
        {
            clearError();
            if (!drv_closeDatabase())
                return false;
            *cancelled = true;
            return false;
        }
    }
 
    if (d->res == SQLITE_CANTOPEN_WITH_LOCKED_READWRITE) {
        setError(ERR_ACCESS_RIGHTS, 
        i18n("The file is probably already open on this or another computer.")+"\n\n"
        + i18n("Could not gain exclusive access for reading and writing the file.") + " "
        + i18n("Check the file's permissions and whether it is already opened and locked by another application."));
    }
    else if (d->res == SQLITE_CANTOPEN_WITH_LOCKED_WRITE) {
        setError(ERR_ACCESS_RIGHTS, 
        i18n("The file is probably already open on this or another computer.")+"\n\n"
        + i18n("Could not gain exclusive access for writing the file.") + " "
        + i18n("Check the file's permissions and whether it is already opened and locked by another application."));
    }
    return d->res == SQLITE_OK;
#endif
}
 
bool SQLiteConnection::drv_closeDatabase()
{
    if (!d->data)
        return false;
 
#ifdef SQLITE2
    sqlite_close(d->data);
    d->data = 0;
    return true;
#else
    const int res = sqlite_close(d->data);
    if (SQLITE_OK == res) {
        d->data = 0;
        return true;
    }
    if (SQLITE_BUSY==res) {
#if 0 //this is ANNOYING, needs fixing (by closing cursors or waiting)
        setError(ERR_CLOSE_FAILED, i18n("Could not close busy database."));
#else
        return true;
#endif
    }
    return false;
#endif
}
 
bool SQLiteConnection::drv_dropDatabase( const TQString &dbName )
{
    Q_UNUSED(dbName); // Each database is one single SQLite file.
    const TQString filename = data()->fileName();
    if (TQFile(filename).exists() && !TQDir().remove(filename)) {
        setError(ERR_ACCESS_RIGHTS, i18n("Could not remove file \"%1\".")
            .arg(TQDir::convertSeparators(filename)) + " "
            + i18n("Check the file's permissions and whether it is already opened and locked by another application."));
        return false;
    }
    return true;
}
 
//CursorData* SQLiteConnection::drv_createCursor( const TQString& statement )
Cursor* SQLiteConnection::prepareQuery( const TQString& statement, uint cursor_options )
{
    return new SQLiteCursor( this, statement, cursor_options );
}
 
Cursor* SQLiteConnection::prepareQuery( QuerySchema& query, uint cursor_options )
{
    return new SQLiteCursor( this, query, cursor_options );
}
 
bool SQLiteConnection::drv_executeSQL( const TQString& statement )
{
//  KexiDBDrvDbg << "SQLiteConnection::drv_executeSQL(" << statement << ")" <<endl;
//  TQCString st(statement.length()*2);
//  st = escapeString( statement.local8Bit() ); //?
#ifdef SQLITE_UTF8
    d->temp_st = statement.utf8();
#else
    d->temp_st = statement.local8Bit(); //latin1 only
#endif
 
#ifdef KEXI_DEBUG_GUI
    KexiUtils::addKexiDBDebug(TQString("ExecuteSQL (SQLite): ")+statement);
#endif
 
    d->res = sqlite_exec( 
        d->data, 
        (const char*)d->temp_st, 
        0/*callback*/, 
        0,
        &d->errmsg_p );
    d->storeResult();
#ifdef KEXI_DEBUG_GUI
    KexiUtils::addKexiDBDebug(d->res==SQLITE_OK ? "  Success" : "  Failure");
#endif
    return d->res==SQLITE_OK;
}
 
TQ_ULLONG SQLiteConnection::drv_lastInsertRowID()
{
    return (TQ_ULLONG)sqlite_last_insert_rowid(d->data);
}
 
int SQLiteConnection::serverResult()
{
    return d->res==0 ? Connection::serverResult() : d->res;
}
 
TQString SQLiteConnection::serverResultName()
{
    TQString r = 
#ifdef SQLITE2
        TQString::fromLatin1( sqlite_error_string(d->res) );
#else //SQLITE3
        TQString(); //fromLatin1( d->result_name );
#endif
    return r.isEmpty() ? Connection::serverResultName() : r;
}
 
void SQLiteConnection::drv_clearServerResult()
{
    if (!d)
        return;
    d->res = SQLITE_OK;
#ifdef SQLITE2
    d->errmsg_p = 0;
#else
//  d->result_name = 0;
#endif
}
 
TQString SQLiteConnection::serverErrorMsg()
{
    return d->errmsg.isEmpty() ? Connection::serverErrorMsg() : d->errmsg;
}
 
PreparedStatement::Ptr SQLiteConnection::prepareStatement(PreparedStatement::StatementType type, 
    FieldList& fields)
{
//#ifndef SQLITE2 //TEMP IFDEF!
    return new SQLitePreparedStatement(type, *d, fields);
//#endif
}
 
bool SQLiteConnection::isReadOnly() const
{
#ifdef SQLITE2
    return Connection::isReadOnly();
#else
    return d->data ? sqlite3_is_readonly(d->data) : false;
#endif
}
 
#ifdef SQLITE2
bool SQLiteConnection::drv_alterTableName(TableSchema& tableSchema, const TQString& newName, bool replace)
{
    const TQString oldTableName = tableSchema.name();
    const bool destTableExists = this->tableSchema( newName ) != 0;
 
    //1. drop the table
    if (destTableExists) {
        if (!replace)
            return false;
        if (!drv_dropTable( newName ))
            return false;
    }
 
    //2. create a copy of the table
//TODO: move this code to drv_copyTable()
    tableSchema.setName(newName);
 
//helper:
#define drv_alterTableName_ERR \
        tableSchema.setName(oldTableName) //restore old name
 
    if (!drv_createTable( tableSchema )) {
        drv_alterTableName_ERR;
        return false;
    }
 
//TODO indices, etc.???
 
    // 3. copy all rows to the new table
    if (!executeSQL(TQString::fromLatin1("INSERT INTO %1 SELECT * FROM %2")
        .arg(escapeIdentifier(tableSchema.name())).arg(escapeIdentifier(oldTableName))))
    {
        drv_alterTableName_ERR;
        return false;
    }
 
    // 4. drop old table.
    if (!drv_dropTable( oldTableName )) {
        drv_alterTableName_ERR;
        return false;
    }
    return true;
}
#endif
 
#include "sqliteconnection.moc"