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See Release Notes

  • Bug fixes for general core bugs in 3.11.x will end 14 Nov 2022 (12 months plus 6 months extension).
  • Bug fixes for security issues in 3.11.x will end 13 Nov 2023 (18 months plus 12 months extension).
  • PHP version: minimum PHP 7.3.0 Note: minimum PHP version has increased since Moodle 3.10. PHP 7.4.x is supported too.

Differences Between: [Versions 310 and 311] [Versions 311 and 400] [Versions 311 and 401] [Versions 311 and 402] [Versions 311 and 403] [Versions 39 and 311]

   1  <?php
   2  
   3  /// $Id $
   4  
   5  ///////////////////////////////////////////////////////////////////////////
   6  //                                                                       //
   7  // NOTICE OF COPYRIGHT                                                   //
   8  //                                                                       //
   9  // ADOdb  - Database Abstraction Library for PHP                         //
  10  //                                                                       //
  11  // Latest version is available at https://adodb.org                       //
  12  //                                                                       //
  13  // Copyright (c) 2000-2014 John Lim (jlim\@natsoft.com.my)               //
  14  //          All rights reserved.                                         //
  15  //          Released under both BSD license and LGPL library license.    //
  16  //          Whenever there is any discrepancy between the two licenses,  //
  17  //          the BSD license will take precedence                         //
  18  //                                                                       //
  19  // Moodle - Modular Object-Oriented Dynamic Learning Environment         //
  20  //          http://moodle.com                                            //
  21  //                                                                       //
  22  // Copyright (C) 2001-3001 Martin Dougiamas        http://dougiamas.com  //
  23  //           (C) 2001-3001 Eloy Lafuente (stronk7) http://contiento.com  //
  24  //                                                                       //
  25  // This program is free software; you can redistribute it and/or modify  //
  26  // it under the terms of the GNU General Public License as published by  //
  27  // the Free Software Foundation; either version 2 of the License, or     //
  28  // (at your option) any later version.                                   //
  29  //                                                                       //
  30  // This program is distributed in the hope that it will be useful,       //
  31  // but WITHOUT ANY WARRANTY; without even the implied warranty of        //
  32  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         //
  33  // GNU General Public License for more details:                          //
  34  //                                                                       //
  35  //          http://www.gnu.org/copyleft/gpl.html                         //
  36  //                                                                       //
  37  ///////////////////////////////////////////////////////////////////////////
  38  
  39  /**
  40  *  MSSQL Driver with auto-prepended "N" for correct unicode storage
  41  *  of SQL literal strings. Intended to be used with MSSQL drivers that
  42  *  are sending UCS-2 data to MSSQL (FreeTDS and ODBTP) in order to get
  43  *  true cross-db compatibility from the application point of view.
  44  */
  45  
  46  // security - hide paths
  47  if (!defined('ADODB_DIR')) die();
  48  
  49  // one useful constant
  50  if (!defined('SINGLEQUOTE')) define('SINGLEQUOTE', "'");
  51  
  52  include_once(ADODB_DIR.'/drivers/adodb-mssql.inc.php');
  53  
  54  class ADODB_mssql_n extends ADODB_mssql {
  55  	 var $databaseType = "mssql_n";
  56  
  57  	function _query($sql,$inputarr=false)
  58  	 {
  59          $sql = $this->_appendN($sql);
  60  	 	 return ADODB_mssql::_query($sql,$inputarr);
  61  	 }
  62  
  63           /**
  64       * This function will intercept all the literals used in the SQL, prepending the "N" char to them
  65       * in order to allow mssql to store properly data sent in the correct UCS-2 encoding (by freeTDS
  66       * and ODBTP) keeping SQL compatibility at ADOdb level (instead of hacking every project to add
  67       * the "N" notation when working against MSSQL.
  68       *
  69       * The original note indicated that this hack should only be used if ALL the char-based columns
  70       * in your DB are of type nchar, nvarchar and ntext, but testing seems to indicate that SQL server
  71       * doesn't seem to care if the statement is used against char etc fields.
  72       *
  73       * @todo This function should raise an ADOdb error if one of the transformations fail
  74       *
  75       * @param mixed $inboundData Either a string containing an SQL statement
  76       *                           or an array with resources from prepared statements
  77       *
  78       * @return mixed
  79       */
  80      function _appendN($inboundData) {
  81  
  82          $inboundIsArray  = false;
  83  
  84          if (is_array($inboundData))
  85          {
  86              $inboundIsArray = true;
  87              $inboundArray   = $inboundData;
  88          } else
  89              $inboundArray = (array)$inboundData;
  90  
  91          /*
  92           * All changes will be placed here
  93           */
  94          $outboundArray = $inboundArray;
  95  
  96          foreach($inboundArray as $inboundKey=>$inboundValue)
  97          {
  98  
  99              if (is_resource($inboundValue))
 100              {
 101                  /*
 102                  * Prepared statement resource
 103                  */
 104                  if ($this->debug)
 105                      ADOConnection::outp("{$this->databaseType} index $inboundKey value is resource, continue");
 106  
 107                  continue;
 108              }
 109  
 110              if (strpos($inboundValue, SINGLEQUOTE) === false)
 111              {
 112                  /*
 113                  * Check we have something to manipulate
 114                  */
 115                  if ($this->debug)
 116                      ADOConnection::outp("{$this->databaseType} index $inboundKey value $inboundValue has no single quotes, continue");
 117                  continue;
 118              }
 119  
 120              /*
 121              * Check we haven't an odd number of single quotes (this can cause problems below
 122              * and should be considered one wrong SQL). Exit with debug info.
 123              */
 124              if ((substr_count($inboundValue, SINGLEQUOTE) & 1))
 125              {
 126                  if ($this->debug)
 127                      ADOConnection::outp("{$this->databaseType} internal transformation: not converted. Wrong number of quotes (odd)");
 128  
 129                  break;
 130              }
 131  
 132              /*
 133              * Check we haven't any backslash + single quote combination. It should mean wrong
 134              *  backslashes use (bad magic_quotes_sybase?). Exit with debug info.
 135              */
 136              $regexp = '/(\\\\' . SINGLEQUOTE . '[^' . SINGLEQUOTE . '])/';
 137              if (preg_match($regexp, $inboundValue))
 138              {
 139                  if ($this->debug)
 140                      ADOConnection::outp("{$this->databaseType} internal transformation: not converted. Found bad use of backslash + single quote");
 141  
 142                  break;
 143              }
 144  
 145              /*
 146              * Remove pairs of single-quotes
 147              */
 148              $pairs = array();
 149              $regexp = '/(' . SINGLEQUOTE . SINGLEQUOTE . ')/';
 150              preg_match_all($regexp, $inboundValue, $list_of_pairs);
 151  
 152              if ($list_of_pairs)
 153              {
 154                  foreach (array_unique($list_of_pairs[0]) as $key=>$value)
 155                      $pairs['<@#@#@PAIR-'.$key.'@#@#@>'] = $value;
 156  
 157  
 158                  if (!empty($pairs))
 159                      $inboundValue = str_replace($pairs, array_keys($pairs), $inboundValue);
 160  
 161              }
 162  
 163              /*
 164              * Remove the rest of literals present in the query
 165              */
 166              $literals = array();
 167              $regexp = '/(N?' . SINGLEQUOTE . '.*?' . SINGLEQUOTE . ')/is';
 168              preg_match_all($regexp, $inboundValue, $list_of_literals);
 169  
 170             if ($list_of_literals)
 171             {
 172                  foreach (array_unique($list_of_literals[0]) as $key=>$value)
 173                      $literals['<#@#@#LITERAL-'.$key.'#@#@#>'] = $value;
 174  
 175  
 176                  if (!empty($literals))
 177                      $inboundValue = str_replace($literals, array_keys($literals), $inboundValue);
 178              }
 179  
 180              /*
 181              * Analyse literals to prepend the N char to them if their contents aren't numeric
 182              */
 183              if (!empty($literals))
 184              {
 185                  foreach ($literals as $key=>$value) {
 186                      if (!is_numeric(trim($value, SINGLEQUOTE)))
 187                          /*
 188                          * Non numeric string, prepend our dear N, whilst
 189                          * Trimming potentially existing previous "N"
 190                          */
 191                          $literals[$key] = 'N' . trim($value, 'N');
 192  
 193                  }
 194              }
 195  
 196              /*
 197              * Re-apply literals to the text
 198              */
 199              if (!empty($literals))
 200                  $inboundValue = str_replace(array_keys($literals), $literals, $inboundValue);
 201  
 202  
 203              /*
 204              * Any pairs followed by N' must be switched to N' followed by those pairs
 205              * (or strings beginning with single quotes will fail)
 206              */
 207              $inboundValue = preg_replace("/((<@#@#@PAIR-(\d+)@#@#@>)+)N'/", "N'$1", $inboundValue);
 208  
 209              /*
 210              * Re-apply pairs of single-quotes to the text
 211              */
 212              if (!empty($pairs))
 213                  $inboundValue = str_replace(array_keys($pairs), $pairs, $inboundValue);
 214  
 215  
 216              /*
 217              * Print transformation if debug = on
 218              */
 219              if (strcmp($inboundValue,$inboundArray[$inboundKey]) <> 0 && $this->debug)
 220                  ADOConnection::outp("{$this->databaseType} internal transformation: {$inboundArray[$inboundKey]} to {$inboundValue}");
 221  
 222              if (strcmp($inboundValue,$inboundArray[$inboundKey]) <> 0)
 223                  /*
 224                  * Place the transformed value into the outbound array
 225                  */
 226                  $outboundArray[$inboundKey] = $inboundValue;
 227          }
 228  
 229          /*
 230           * Any transformations are in the $outboundArray
 231           */
 232          if ($inboundIsArray)
 233              return $outboundArray;
 234  
 235          /*
 236           * We passed a string in originally
 237           */
 238          return $outboundArray[0];
 239  
 240      }
 241  
 242  }
 243  
 244  class ADORecordset_mssql_n extends ADORecordset_mssql {
 245  	 var $databaseType = "mssql_n";
 246  }