library/adodb/drivers/adodb-mssql_n.inc.php

   1 <?php
   2
   3 /// $Id $
   4
   5 ///////////////////////////////////////////////////////////////////////////
   6 //                                                                       //
   7 // NOTICE OF COPYRIGHT                                                   //
   8 //                                                                       //
   9 // ADOdb  - Database Abstraction Library for PHP                         //
  10 //          http://adodb.sourceforge.net/                                //
  11 //                                                                       //
  12 // Copyright (c) 2000-2011 John Lim (jlim\@natsoft.com.my)               //
  13 //          All rights reserved.                                         //
  14 //          Released under both BSD license and LGPL library license.    //
  15 //          Whenever there is any discrepancy between the two licenses,  //
  16 //          the BSD license will take precedence                         //
  17 //                                                                       //
  18 // Moodle - Modular Object-Oriented Dynamic Learning Environment         //
  19 //          http://moodle.com                                            //
  20 //                                                                       //
  21 // Copyright (C) 2001-3001 Martin Dougiamas        http://dougiamas.com  //
  22 //           (C) 2001-3001 Eloy Lafuente (stronk7) http://contiento.com  //
  23 //                                                                       //
  24 // This program is free software; you can redistribute it and/or modify  //
  25 // it under the terms of the GNU General Public License as published by  //
  26 // the Free Software Foundation; either version 2 of the License, or     //
  27 // (at your option) any later version.                                   //
  28 //                                                                       //
  29 // This program is distributed in the hope that it will be useful,       //
  30 // but WITHOUT ANY WARRANTY; without even the implied warranty of        //
  31 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         //
  32 // GNU General Public License for more details:                          //
  33 //                                                                       //
  34 //          http://www.gnu.org/copyleft/gpl.html                         //
  35 //                                                                       //
  36 ///////////////////////////////////////////////////////////////////////////
  37
  38 /**
  39 *  MSSQL Driver with auto-prepended "N" for correct unicode storage
  40 *  of SQL literal strings. Intended to be used with MSSQL drivers that
  41 *  are sending UCS-2 data to MSSQL (FreeTDS and ODBTP) in order to get
  42 *  true cross-db compatibility from the application point of view.
  43 */
  44
  45 // security - hide paths
  46 if (!defined('ADODB_DIR')) die();
  47
  48 // one useful constant
  49 if (!defined('SINGLEQUOTE')) define('SINGLEQUOTE', "'");
  50
  51 include_once(ADODB_DIR.'/drivers/adodb-mssql.inc.php');
  52
  53 class ADODB_mssql_n extends ADODB_mssql {
  54         var $databaseType = "mssql_n";
  55
  56         function ADODB_mssqlpo()
  57         {
  58                 ADODB_mssql::ADODB_mssql();
  59         }
  60
  61         function _query($sql,$inputarr=false)
  62         {
  63         $sql = $this->_appendN($sql);
  64                 return ADODB_mssql::_query($sql,$inputarr);
  65         }
  66
  67     /**
  68      * This function will intercept all the literals used in the SQL, prepending the "N" char to them
  69      * in order to allow mssql to store properly data sent in the correct UCS-2 encoding (by freeTDS
  70      * and ODBTP) keeping SQL compatibility at ADOdb level (instead of hacking every project to add
  71      * the "N" notation when working against MSSQL.
  72      *
  73      * Note that this hack only must be used if ALL the char-based columns in your DB are of type nchar,
  74      * nvarchar and ntext
  75      */
  76     function _appendN($sql) {
  77
  78         $result = $sql;
  79
  80     /// Check we have some single quote in the query. Exit ok.
  81         if (strpos($sql, SINGLEQUOTE) === false) {
  82             return $sql;
  83         }
  84
  85     /// Check we haven't an odd number of single quotes (this can cause problems below
  86     /// and should be considered one wrong SQL). Exit with debug info.
  87         if ((substr_count($sql, SINGLEQUOTE) & 1)) {
  88             if ($this->debug) {
  89                 ADOConnection::outp("{$this->databaseType} internal transformation: not converted. Wrong number of quotes (odd)");
  90             }
  91             return $sql;
  92         }
  93
  94     /// Check we haven't any backslash + single quote combination. It should mean wrong
  95     /// backslashes use (bad magic_quotes_sybase?). Exit with debug info.
  96         $regexp = '/(\\\\' . SINGLEQUOTE . '[^' . SINGLEQUOTE . '])/';
  97         if (preg_match($regexp, $sql)) {
  98             if ($this->debug) {
  99                 ADOConnection::outp("{$this->databaseType} internal transformation: not converted. Found bad use of backslash + single quote");
 100             }
 101             return $sql;
 102         }
 103
 104     /// Remove pairs of single-quotes
 105         $pairs = array();
 106         $regexp = '/(' . SINGLEQUOTE . SINGLEQUOTE . ')/';
 107         preg_match_all($regexp, $result, $list_of_pairs);
 108         if ($list_of_pairs) {
 109             foreach (array_unique($list_of_pairs[0]) as $key=>$value) {
 110                 $pairs['<@#@#@PAIR-'.$key.'@#@#@>'] = $value;
 111             }
 112             if (!empty($pairs)) {
 113                 $result = str_replace($pairs, array_keys($pairs), $result);
 114             }
 115         }
 116
 117     /// Remove the rest of literals present in the query
 118         $literals = array();
 119         $regexp = '/(N?' . SINGLEQUOTE . '.*?' . SINGLEQUOTE . ')/is';
 120         preg_match_all($regexp, $result, $list_of_literals);
 121         if ($list_of_literals) {
 122             foreach (array_unique($list_of_literals[0]) as $key=>$value) {
 123                 $literals['<#@#@#LITERAL-'.$key.'#@#@#>'] = $value;
 124             }
 125             if (!empty($literals)) {
 126                 $result = str_replace($literals, array_keys($literals), $result);
 127             }
 128         }
 129
 130
 131     /// Analyse literals to prepend the N char to them if their contents aren't numeric
 132         if (!empty($literals)) {
 133             foreach ($literals as $key=>$value) {
 134                 if (!is_numeric(trim($value, SINGLEQUOTE))) {
 135                 /// Non numeric string, prepend our dear N
 136                     $literals[$key] = 'N' . trim($value, 'N'); //Trimming potentially existing previous "N"
 137                 }
 138             }
 139         }
 140
 141     /// Re-apply literals to the text
 142         if (!empty($literals)) {
 143             $result = str_replace(array_keys($literals), $literals, $result);
 144         }
 145
 146     /// Any pairs followed by N' must be switched to N' followed by those pairs
 147     /// (or strings beginning with single quotes will fail)
 148         $result = preg_replace("/((<@#@#@PAIR-(\d+)@#@#@>)+)N'/", "N'$1", $result);
 149
 150     /// Re-apply pairs of single-quotes to the text
 151         if (!empty($pairs)) {
 152             $result = str_replace(array_keys($pairs), $pairs, $result);
 153         }
 154
 155     /// Print transformation if debug = on
 156         if ($result != $sql && $this->debug) {
 157             ADOConnection::outp("{$this->databaseType} internal transformation:<br>{$sql}<br>to<br>{$result}");
 158         }
 159
 160         return $result;
 161     }
 162 }
 163
 164 class ADORecordset_mssql_n extends ADORecordset_mssql {
 165         var $databaseType = "mssql_n";
 166         function ADORecordset_mssql_n($id,$mode=false)
 167         {
 168                 $this->ADORecordset_mssql($id,$mode);
 169         }
 170 }
 171 ?>