sqlite.php

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<?php
/* vim: set expandtab tabstop=4 shiftwidth=4 foldmethod=marker: */
// +----------------------------------------------------------------------+
// | PHP Version 4                                                        |
// +----------------------------------------------------------------------+
// | Copyright (c) 1997-2004 The PHP Group                                |
// +----------------------------------------------------------------------+
// | This source file is subject to version 2.02 of the PHP license,      |
// | that is bundled with this package in the file LICENSE, and is        |
// | available at through the world-wide-web at                           |
// | http://www.php.net/license/2_02.txt.                                 |
// | If you did not receive a copy of the PHP license and are unable to   |
// | obtain it through the world-wide-web, please send a note to          |
// | [e-mail] so we can mail you a copy immediately.               |
// +----------------------------------------------------------------------+
// | Authors: Urs Gehrig <[e-mail]>                                  |
// |          Mika Tuupola <[e-mail]>                       |
// | Maintainer: Daniel Convissor <[e-mail]>                       |
// +----------------------------------------------------------------------+
//
// $Id: sqlite.php 3355 2005-06-11 22:14:40Z nbm $

require_once 'DB/common.php';

/**
 * Database independent query interface definition for the SQLite
 * PECL extension.
 *
 * @package  DB
 * @version  $Id: sqlite.php 3355 2005-06-11 22:14:40Z nbm $
 * @category Database
 * @author   Urs Gehrig <[e-mail]>
 * @author   Mika Tuupola <[e-mail]>
 */
class DB_sqlite extends DB_common
{
    // {{{ properties

    var $connection;
    var $phptype, $dbsyntax;
    var $prepare_tokens = array();
    var $prepare_types = array();
    var $_lasterror = '';

    // }}}
    // {{{ constructor

    /**
     * Constructor for this class.
     *
     * Error codes according to sqlite_exec.  Error Codes specification is
     * in the {@link http://sqlite.org/c_interface.html online manual}.
     *
     * This errorhandling based on sqlite_exec is not yet implemented.
     *
     * @access public
     */
    function DB_sqlite()
    {

        $this->DB_common();
        $this->phptype = 'sqlite';
        $this->dbsyntax = 'sqlite';
        $this->features = array (
            'prepare' => false,
            'pconnect' => true,
            'transactions' => false,
            'limit' => 'alter'
        );

        // SQLite data types, http://www.sqlite.org/datatypes.html
        $this->keywords = array (
            'BLOB'      => '',
            'BOOLEAN'   => '',
            'CHARACTER' => '',
            'CLOB'      => '',
            'FLOAT'     => '',
            'INTEGER'   => '',
            'KEY'       => '',
            'NATIONAL'  => '',
            'NUMERIC'   => '',
            'NVARCHAR'  => '',
            'PRIMARY'   => '',
            'TEXT'      => '',
            'TIMESTAMP' => '',
            'UNIQUE'    => '',
            'VARCHAR'   => '',
            'VARYING'   => ''
        );
        $this->errorcode_map = array(
        );
    }

    // }}}
    // {{{ connect()

    /**
     * Connect to a database represented by a file.
     *
     * @param $dsn the data source name; the file is taken as
     *        database; "sqlite://root:@host/test.db?mode=0644"
     * @param $persistent (optional) whether the connection should
     *        be persistent
     * @access public
     * @return int DB_OK on success, a DB error on failure
     */
    function connect($dsninfo, $persistent = false)
    {
        if (!DB::assertExtension('sqlite')) {
            return $this->raiseError(DB_ERROR_EXTENSION_NOT_FOUND);
        }

        $this->dsn = $dsninfo;

        if ($dsninfo['database']) {
            if (!file_exists($dsninfo['database'])) {
                if (!touch($dsninfo['database'])) {
                    return $this->sqliteRaiseError(DB_ERROR_NOT_FOUND);
                }
                if (!isset($dsninfo['mode']) ||
                    !is_numeric($dsninfo['mode']))
                {
                    $mode = 0644;
                } else {
                    $mode = octdec($dsninfo['mode']);
                }
                if (!chmod($dsninfo['database'], $mode)) {
                    return $this->sqliteRaiseError(DB_ERROR_NOT_FOUND);
                }
                if (!file_exists($dsninfo['database'])) {
                    return $this->sqliteRaiseError(DB_ERROR_NOT_FOUND);
                }
            }
            if (!is_file($dsninfo['database'])) {
                return $this->sqliteRaiseError(DB_ERROR_INVALID);
            }
            if (!is_readable($dsninfo['database'])) {
                return $this->sqliteRaiseError(DB_ERROR_ACCESS_VIOLATION);
            }
        } else {
            return $this->sqliteRaiseError(DB_ERROR_ACCESS_VIOLATION);
        }

        $connect_function = $persistent ? 'sqlite_popen' : 'sqlite_open';
        if (!($conn = @$connect_function($dsninfo['database']))) {
            return $this->sqliteRaiseError(DB_ERROR_NODBSELECTED);
        }
        $this->connection = $conn;

        return DB_OK;
    }

    // }}}
    // {{{ disconnect()

    /**
     * Log out and disconnect from the database.
     *
     * @access public
     * @return bool true on success, false if not connected.
     * @todo fix return values
     */
    function disconnect()
    {
        $ret = @sqlite_close($this->connection);
        $this->connection = null;
        return $ret;
    }

    // }}}
    // {{{ simpleQuery()

    /**
     * Send a query to SQLite and returns the results as a SQLite resource
     * identifier.
     *
     * @param the SQL query
     * @access public
     * @return mixed returns a valid SQLite result for successful SELECT
     * queries, DB_OK for other successful queries. A DB error is
     * returned on failure.
     */
    function simpleQuery($query)
    {
        $ismanip = DB::isManip($query);
        $this->last_query = $query;
        $query = $this->_modifyQuery($query);
        ini_set('track_errors', true);
        $result = @sqlite_query($query, $this->connection);
        ini_restore('track_errors');
        $this->_lasterror = isset($php_errormsg) ? $php_errormsg : '';
        $this->result = $result;
        if (!$this->result) {
            return $this->sqliteRaiseError(null);
        }

        /* sqlite_query() seems to allways return a resource */
        /* so cant use that. Using $ismanip instead          */
        if (!$ismanip) {
            $numRows = $this->numRows($result);

            /* if numRows() returned PEAR_Error */
            if (is_object($numRows)) {
                return $numRows;
            }
            return $result;
        }
        return DB_OK;
    }

    // }}}
    // {{{ nextResult()

    /**
     * Move the internal sqlite result pointer to the next available result.
     *
     * @param a valid sqlite result resource
     * @access public
     * @return true if a result is available otherwise return false
     */
    function nextResult($result)
    {
        return false;
    }

    // }}}
    // {{{ fetchInto()

    /**
     * Fetch a row and insert the data into an existing array.
     *
     * Formating of the array and the data therein are configurable.
     * See DB_result::fetchInto() for more information.
     *
     * @param resource $result    query result identifier
     * @param array    $arr       (reference) array where data from the row
     *                            should be placed
     * @param int      $fetchmode how the resulting array should be indexed
     * @param int      $rownum    the row number to fetch
     *
     * @return mixed DB_OK on success, null when end of result set is
     *               reached or on failure
     *
     * @see DB_result::fetchInto()
     * @access private
     */
    function fetchInto($result, &$arr, $fetchmode, $rownum=null)
    {
        if ($rownum !== null) {
            if (!@sqlite_seek($this->result, $rownum)) {
                return null;
            }
        }
        if ($fetchmode & DB_FETCHMODE_ASSOC) {
            $arr = @sqlite_fetch_array($result, SQLITE_ASSOC);
            if ($this->options['portability'] & DB_PORTABILITY_LOWERCASE && $arr) {
                $arr = array_change_key_case($arr, CASE_LOWER);
            }
        } else {
            $arr = @sqlite_fetch_array($result, SQLITE_NUM);
        }
        if (!$arr) {
            /* See: http://bugs.php.net/bug.php?id=22328 */
            return null;
        }
        if ($this->options['portability'] & DB_PORTABILITY_RTRIM) {
            /*
             * Even though this DBMS already trims output, we do this because
             * a field might have intentional whitespace at the end that
             * gets removed by DB_PORTABILITY_RTRIM under another driver.
             */
            $this->_rtrimArrayValues($arr);
        }
        if ($this->options['portability'] & DB_PORTABILITY_NULL_TO_EMPTY) {
            $this->_convertNullArrayValuesToEmpty($arr);
        }
        return DB_OK;
    }

    // }}}
    // {{{ freeResult()

    /**
     * Free the internal resources associated with $result.
     *
     * @param $result SQLite result identifier
     * @access public
     * @return bool true on success, false if $result is invalid
     */
    function freeResult(&$result)
    {
        // XXX No native free?
        if (!is_resource($result)) {
            return false;
        }
        $result = null;
        return true;
    }

    // }}}
    // {{{ numCols()

    /**
     * Gets the number of columns in a result set.
     *
     * @return number of columns in a result set
     */
    function numCols($result)
    {
        $cols = @sqlite_num_fields($result);
        if (!$cols) {
            return $this->sqliteRaiseError();
        }
        return $cols;
    }

    // }}}
    // {{{ numRows()

    /**
     * Gets the number of rows affected by a query.
     *
     * @return number of rows affected by the last query
     */
    function numRows($result)
    {
        $rows = @sqlite_num_rows($result);
        if (!is_integer($rows)) {
            return $this->raiseError();
        }
        return $rows;
    }

    // }}}
    // {{{ affected()

    /**
     * Gets the number of rows affected by a query.
     *
     * @return number of rows affected by the last query
     */
    function affectedRows()
    {
        return @sqlite_changes($this->connection);
    }

    // }}}
    // {{{ errorNative()