AmigActive 15/AACD15.ISO/AACD/Magazine/HomeAutomation/Apache/lib/php/DB/common.php

PHP Script | 2000-07-11 | 10.1 KB | 374 lines

<?php
//
// +----------------------------------------------------------------------+
// | PHP version 4.0                                                      |
// +----------------------------------------------------------------------+
// | Copyright (c) 1997, 1998, 1999, 2000 The PHP Group                   |
// +----------------------------------------------------------------------+
// | This source file is subject to version 2.0 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_0.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: Stig Bakken <[e-mail]>                                   |
// |                                                                      |
// +----------------------------------------------------------------------+
//
// Base class for DB implementations.
//

//
// XXX legend:
//
// XXX ERRORMSG: Needs a better way of dealing with errors.
// XXX ADDREF:     As soon as Zend/PHP gets support for returning
//                 references, this return value should be made into
//                 a reference.
//

if (!empty($GLOBALS['USED_PACKAGES']['DB/common'])) return;
$GLOBALS['USED_PACKAGES']['DB/common'] = true;

/**
 * DB_common is a base class for DB implementations, and should be
 * inherited by all such.
 */
class DB_common {
    // {{{ properties

    var $features;        // assoc of capabilities for this DB implementation
    var $errorcode_map;    // assoc mapping native error codes to DB ones
    var $type;            // DB type (mysql, oci8, odbc etc.)

    // }}}
    // {{{ constructor

    function DB_common() {
        $this->features = array();
        $this->errorcode_map = array();
    }

    // }}}
    // {{{ quoteString()

    /**
     * Quotes a string so it can be safely used within string delimiters
     * in a query.
     *
     * @param $string the input string to quote
     *
     * @return string the quoted string
     */
    function quoteString($string) {
        return str_replace("'", "\'", $string);
    }

    // }}}
    // {{{ provides()

    /**
     * Tell whether a DB implementation or its backend extension
     * supports a given feature.
     *
     * @param $feature name of the feature (see the DB class doc)
     *
     * @return bool whether this DB implementation supports $feature
     */
    function provides($feature) {
        return $this->features[$feature];
    }

    // }}}
    // {{{ errorCode()

    /**
     * Map native error codes to DB's portable ones.  Requires that
     * the DB implementation's constructor fills in the $errorcode_map
     * property.
     *
     * @param $nativecode the native error code, as returned by the backend
     * database extension (string or integer)
     *
     * @return int a portable DB error code, or FALSE if this DB
     * implementation has no mapping for the given error code.
     */
    function errorCode($nativecode) {
        if ($this->errorcode_map[$nativecode]) {
            return $this->errorcode_map[$nativecode];
        }
        //php_error(E_WARNING, get_class($this)."::errorCode: no mapping for $nativecode");
        // Fall back to DB_ERROR if there was no mapping.  Ideally,
        // this should never happen.
        return DB_ERROR;
    }

    // }}}
    // {{{ errorMessage()

    /**
     * Map a DB error code to a textual message.  This is actually
     * just a wrapper for DB::errorMessage().
     *
     * @param $dbcode the DB error code
     *
     * @return string the corresponding error message, of FALSE
     * if the error code was unknown
     */
    function errorMessage($dbcode) {
        return DB::errorMessage($this->errorcode_map[$dbcode]);
    }

    // }}}

    // {{{ prepare()

    /**
     * Prepares a query for multiple execution with execute().  With
     * PostgreSQL, this is emulated.
     */
    function prepare($query) {
        $tokens = split('[\&\?]', $query);
        $token = 0;
        $types = array();
        for ($i = 0; $i < strlen($query); $i++) {
            switch ($query[$i]) {
                case '?':
                    $types[$token++] = DB_PARAM_SCALAR;
                    break;
                case '&':
                    $types[$token++] = DB_PARAM_OPAQUE;
                    break;
            }
        }
        $this->prepare_tokens[] = &$tokens;
        end($this->prepare_tokens);
        $k = key($this->prepare_tokens);
        $this->prepare_types[$k] = $types;
        return $k;
    }

    // }}}
    // {{{ execute_emulate_query()

    /**
     * @return a string containing the real query run when emulating
     * prepare/execute.  A DB error code is returned on failure.
     */
    function execute_emulate_query($stmt, $data = false) {
        $p = &$this->prepare_tokens;
        $stmt = 0; // XXX HORRIBLE HACK
        if (!isset($this->prepare_tokens[$stmt]) ||
            !is_array($this->prepare_tokens[$stmt]) ||
            !sizeof($this->prepare_tokens[$stmt])) {
            return DB_ERROR_INVALID;
        }
        $qq = &$this->prepare_tokens[$stmt];
        $qp = sizeof($qq) - 1;
        if ((!$data && $qp > 0) ||
            (!is_array($data) && $qp > 1) ||
            (is_array($data) && $qp > sizeof($data))) {
            return DB_ERROR_NEED_MORE_DATA;
        }
        $realquery = $qq[0];
        for ($i = 0; $i < $qp; $i++) {
            if ($this->prepare_types[$stmt][$i] == DB_PARAM_OPAQUE) {
                if (is_array($data)) {
                    $fp = fopen($data[$i], "r");
                } else {
                    $fp = fopen($data, "r");
                }
                $pdata = '';
                if ($fp) {
                    while (($buf = fread($fp, 4096)) != false) {
                        $pdata .= $buf;
                    }
                }
            } else {
                if (is_array($data)) {
                    $pdata = &$data[$i];
                } else {
                    $pdata = &$data;
                }
            }
            $realquery .= "'" . $this->quoteString($pdata) . "'";
            $realquery .= $qq[$i + 1];
        }
        return $realquery;
    }

    // }}}

    // {{{ executeMultiple()

    /**
     * This function does several execute() calls on the same
     * statement handle.  $data must be an array indexed numerically
     * from 0, one execute call is done for every "row" in the array.
     *
     * If an error occurs during execute(), executeMultiple() does not
     * execute the unfinished rows, but rather returns that error.
     */
    function executeMultiple($stmt, &$data) {
        for ($i = 0; $i < sizeof($data); $i++) {
            $res = $this->execute($stmt, &$data[$i]);
            if (DB::isError($res)) {
                return $res;
            }
        }
        return DB_OK;
    }

    // }}}
    // {{{ getOne()

    /**
     * Fetch the first column of the first row of data returned from
     * a query.  Takes care of doing the query and freeing the results
     * when finished.
     *
     * @param $query the SQL query
     * @param $params is supplies, prepare/execute will be used
     *        with this array as execute parameters
     */
    function &getOne($query, $params = array()) {
        if (sizeof($params) > 0) {
            $sth = $this->prepare($query);
            if (DB::isError($sth)) {
                return $sth;
            }
            $res = $this->execute($sth, &$params);
        } else {
            $res = $this->simpleQuery($query);
        }
        if (DB::isError($res)) {
            return $res;
        }
        $row = $this->fetchRow($res, DB_GETMODE_ORDERED);
        if (DB::isError($row)) {
            return $row;
        }
        $ret = &$row[0];
        $this->freeResult($res);
        return $ret;
    }

    // }}}
    // {{{ getRow()

    /**
     * Fetch the first row of data returned from a query.  Takes care
     * of doing the query and freeing the results when finished.
     *
     * @param $query the SQL query
     * @return array the first row of results as an array indexed from
     * 0, or a DB error code.
     */
    function &getRow($query, $getmode = DB_GETMODE_DEFAULT, $params = array()) {
        $res = $this->simpleQuery($query);
        if (DB::isError($res)) {
            return $res;
        }
        $row = $this->fetchRow($res, $getmode);
        if (DB::isError($row)) {
            return $row;
        }
        $this->freeResult($res);
        return $row;
    }

    // }}}
    // {{{ getAssoc()

    /**
     * Fetch the entire result set of a query and return it as an
     * associative array using the first column as the key.
     *
     * @param $query the SQL query
     *
     * @param $force_array (optional) used only when the query returns
     * exactly two columns.  If true, the values of the returned array
     * will be one-element arrays instead of scalars.
     *
     * @return array associative array with results from the query.
     * If the result set contains more than two columns, the value
     * will be an array of the values from column 2-n.  If the result
     * set contains only two columns, the returned value will be a
     * scalar with the value of the second column (unless forced to an
     * array with the $force_array parameter).  A DB error code is
     * returned on errors.  If the result set contains fewer than two
     * columns, DB_ERROR_TRUNCATED is returned.
     *
     * For example, if the table "mytable" contains:
     *
     *  ID      TEXT       DATE
     * --------------------------------
     *  1       'one'      944679408
     *  2       'two'      944679408
     *  3       'three'    944679408
     *
     * Then the call getAssoc('SELECT id,text FROM mytable') returns:
     *   array(
     *     '1' => 'one',
     *     '2' => 'two',
     *     '3' => 'three',
     *   )
     *
     * ...while the call getAssoc('SELECT id,text,date FROM mydate') returns:
     *   array(
     *     '1' => array('one', '944679408'),
     *     '2' => array('two', '944679408'),
     *     '3' => array('three', '944679408')
     *   )
     *
     * Keep in mind that database functions in PHP usually return string
     * values for results regardless of the database's internal type.
     */
    function &getAssoc($query, $force_array = false, $params = array()) {
        $res = $this->simpleQuery($query);
        if (DB::isError($res)) {
            return $res;
        }
        $cols = $this->numCols($res);
        if ($cols < 2) {
            return DB_ERROR_TRUNCATED;
        }
        $results = array();
        if ($cols > 2 || $force_array) {
            // return array values
            // XXX this part can be optimized
            while (!DB::isError($row = $this->fetchRow($res))) {
                reset($row);
                // we copy the row of data into a new array
                // to get indices running from 0 again
                for ($i = 1; $i < $cols; $i++) {
                    $results[$row[0]][$i-1] = $row[$i];
                }
            }
        } else {
            // return scalar values
            while (!DB::isError($row = $this->fetchRow($res))) {
                $results[$row[0]] = $row[1];
            }
        }
        return $results; // XXX ADDREF
    }

    // }}}
    // {{{ getAll()

    function &getAll($query, $getmode = DB_GETMODE_DEFAULT, $params = array()) {

    }

    // }}}
}

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?>