db.php

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              $level = E_USER_NOTICE, $debuginfo = null)
    {
        if (is_int($code)) {
            $this->PEAR_Error('DB Error: ' . DB::errorMessage($code), $code, $mode, $level, $debuginfo);
        } else {
            $this->PEAR_Error("DB Error: $code", DB_ERROR, $mode, $level, $debuginfo);
        }
    }
    // }}}
}

// }}}
// {{{ class DB_result

/**
 * This class implements a wrapper for a DB result set.
 * A new instance of this class will be returned by the DB implementation
 * after processing a query that returns data.
 *
 * @package  DB
 * @author Stig Bakken <[e-mail]>
 */
class DB_result
{
    // {{{ properties

    var $dbh;
    var $result;
    var $row_counter = null;

    /**
     * for limit queries, the row to start fetching
     * @var integer
     */
    var $limit_from  = null;

    /**
     * for limit queries, the number of rows to fetch
     * @var integer
     */
    var $limit_count = null;

    // }}}
    // {{{ constructor

    /**
     * DB_result constructor.
     * @param resource &$dbh   DB object reference
     * @param resource $result  result resource id
     * @param array    $options assoc array with optional result options
     */
    function DB_result(&$dbh, $result, $options = array())
    {
        $this->dbh = &$dbh;
        $this->result = $result;
        foreach ($options as $key => $value) {
            $this->setOption($key, $value);
        }
        $this->limit_type  = $dbh->features['limit'];
        $this->autofree    = $dbh->options['autofree'];
        $this->fetchmode   = $dbh->fetchmode;
        $this->fetchmode_object_class = $dbh->fetchmode_object_class;
    }

    function setOption($key, $value = null)
    {
        switch ($key) {
            case 'limit_from':
                $this->limit_from = $value; break;
            case 'limit_count':
                $this->limit_count = $value; break;
        }
    }

    // }}}
    // {{{ fetchRow()

    /**
     * Fetch a row of data and return it by reference into an array.
     *
     * The type of array returned can be controlled either by setting this
     * method's <var>$fetchmode</var> parameter or by changing the default
     * fetch mode setFetchMode() before calling this method.
     *
     * There are two options for standardizing the information returned
     * from databases, ensuring their values are consistent when changing
     * DBMS's.  These portability options can be turned on when creating a
     * new DB object or by using setOption().
     *
     *   + <samp>DB_PORTABILITY_LOWERCASE</samp>
     *     convert names of fields to lower case
     *
     *   + <samp>DB_PORTABILITY_RTRIM</samp>
     *     right trim the data
     *
     * @param int $fetchmode  how the resulting array should be indexed
     * @param int $rownum     the row number to fetch
     *
     * @return array  a row of data, null on no more rows or PEAR_Error
     *                object on error
     *
     * @see DB_common::setOption(), DB_common::setFetchMode()
     * @access public
     */
    function &fetchRow($fetchmode = DB_FETCHMODE_DEFAULT, $rownum=null)
    {
        if ($fetchmode === DB_FETCHMODE_DEFAULT) {
            $fetchmode = $this->fetchmode;
        }
        if ($fetchmode === DB_FETCHMODE_OBJECT) {
            $fetchmode = DB_FETCHMODE_ASSOC;
            $object_class = $this->fetchmode_object_class;
        }
        if ($this->limit_from !== null) {
            if ($this->row_counter === null) {
                $this->row_counter = $this->limit_from;
                // Skip rows
                if ($this->limit_type == false) {
                    $i = 0;
                    while ($i++ < $this->limit_from) {
                        $this->dbh->fetchInto($this->result, $arr, $fetchmode);
                    }
                }
            }
            if ($this->row_counter >= (
                    $this->limit_from + $this->limit_count))
            {
                if ($this->autofree) {
                    $this->free();
                }
                $tmp = null;
                return $tmp;
            }
            if ($this->limit_type == 'emulate') {
                $rownum = $this->row_counter;
            }
            $this->row_counter++;
        }
        $res = $this->dbh->fetchInto($this->result, $arr, $fetchmode, $rownum);
        if ($res === DB_OK) {
            if (isset($object_class)) {
                // default mode specified in DB_common::fetchmode_object_class property
                if ($object_class == 'stdClass') {
                    $arr = (object) $arr;
                } else {
                    $arr = &new $object_class($arr);
                }
            }
            return $arr;
        }
        if ($res == null && $this->autofree) {
            $this->free();
        }
        return $res;
    }

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

    /**
     * Fetch a row of data into an array which is passed by reference.
     *
     * The type of array returned can be controlled either by setting this
     * method's <var>$fetchmode</var> parameter or by changing the default
     * fetch mode setFetchMode() before calling this method.
     *
     * There are two options for standardizing the information returned
     * from databases, ensuring their values are consistent when changing
     * DBMS's.  These portability options can be turned on when creating a
     * new DB object or by using setOption().
     *
     *   + <samp>DB_PORTABILITY_LOWERCASE</samp>
     *     convert names of fields to lower case
     *
     *   + <samp>DB_PORTABILITY_RTRIM</samp>
     *     right trim the data
     *
     * @param array &$arr       (reference) array where data from the row
     *                          should be placed
     * @param int   $fetchmode  how the resulting array should be indexed
     * @param int   $rownum     the row number to fetch
     *
     * @return mixed  DB_OK on success, null on no more rows or
     *                a DB_Error object on error
     *
     * @see DB_common::setOption(), DB_common::setFetchMode()
     * @access public
     */
    function fetchInto(&$arr, $fetchmode = DB_FETCHMODE_DEFAULT, $rownum=null)
    {
        if ($fetchmode === DB_FETCHMODE_DEFAULT) {
            $fetchmode = $this->fetchmode;
        }
        if ($fetchmode === DB_FETCHMODE_OBJECT) {
            $fetchmode = DB_FETCHMODE_ASSOC;
            $object_class = $this->fetchmode_object_class;
        }
        if ($this->limit_from !== null) {
            if ($this->row_counter === null) {
                $this->row_counter = $this->limit_from;
                // Skip rows
                if ($this->limit_type == false) {
                    $i = 0;
                    while ($i++ < $this->limit_from) {
                        $this->dbh->fetchInto($this->result, $arr, $fetchmode);
                    }
                }
            }
            if ($this->row_counter >= (
                    $this->limit_from + $this->limit_count))
            {
                if ($this->autofree) {
                    $this->free();
                }
                return null;
            }
            if ($this->limit_type == 'emulate') {
                $rownum = $this->row_counter;
            }

            $this->row_counter++;
        }
        $res = $this->dbh->fetchInto($this->result, $arr, $fetchmode, $rownum);
        if ($res === DB_OK) {
            if (isset($object_class)) {
                // default mode specified in DB_common::fetchmode_object_class property
                if ($object_class == 'stdClass') {
                    $arr = (object) $arr;
                } else {
                    $arr = new $object_class($arr);
                }
            }
            return DB_OK;
        }
        if ($res == null && $this->autofree) {
            $this->free();
        }
        return $res;
    }

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

    /**
     * Get the the number of columns in a result set.
     *
     * @return int the number of columns, or a DB error
     *
     * @access public
     */
    function numCols()
    {
        return $this->dbh->numCols($this->result);
    }

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

    /**
     * Get the number of rows in a result set.
     *
     * @return int the number of rows, or a DB error
     *
     * @access public
     */
    function numRows()
    {
        return $this->dbh->numRows($this->result);
    }

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

    /**
     * Get the next result if a batch of queries was executed.
     *
     * @return bool true if a new result is available or false if not.
     *
     * @access public
     */
    function nextResult()
    {
        return $this->dbh->nextResult($this->result);
    }

    // }}}
    // {{{ free()

    /**
     * Frees the resources allocated for this result set.
     * @return  int error code
     *
     * @access public
     */
    function free()
    {
        $err = $this->dbh->freeResult($this->result);
        if (DB::isError($err)) {
            return $err;
        }
        $this->result = false;
        return true;
    }

    // }}}
    // {{{ tableInfo()

    /**
     * @deprecated
     * @internal
     * @see DB_common::tableInfo()
     */
    function tableInfo($mode = null)
    {
        if (is_string($mode)) {
            return $this->dbh->raiseError(DB_ERROR_NEED_MORE_DATA);
        }
        return $this->dbh->tableInfo($this, $mode);
    }

    // }}}
    // {{{ getRowCounter()

    /**
     * returns the actual row number
     * @return integer
     */
    function getRowCounter()
    {
        return $this->row_counter;
    }
    // }}}
}

// }}}
// {{{ class DB_row

/**
 * Pear DB Row Object
 * @see DB_common::setFetchMode()
 */
class DB_row
{
    // {{{ constructor

    /**
     * constructor
     *
     * @param resource row data as array
     */
    function DB_row(&$arr)
    {
        foreach ($arr as $key => $value) {
            $this->$key = &$arr[$key];
        }
    }

    // }}}
}

// }}}

/*
 * Local variables:
 * tab-width: 4
 * c-basic-offset: 4
 * End:
 */

?>