libraries/Linter.class.php

   1 <?php
   2 /* vim: set expandtab sw=4 ts=4 sts=4: */
   3 /**
   4  * Analyzes a query and gives user feedback.
   5  *
   6  * @package PhpMyAdmin
   7  */
   8 if (! defined('PHPMYADMIN')) {
   9     exit;
  10 }
  11
  12 /**
  13  * The linter itself.
  14  *
  15  * @package PhpMyAdmin
  16  */
  17 class PMA_Linter
  18 {
  19
  20     /**
  21      * Gets the starting position of each line.
  22      *
  23      * @param string $str String to be analyzed.
  24      *
  25      * @return array
  26      */
  27     public static function getLines($str)
  28     {
  29         $lines = array(0);
  30
  31         // The reason for using the '8bit' parameter is that the length
  32         // required is the length in bytes, not characters.
  33         //
  34         // Given the following string: `????+`, where `?` represents a
  35         // multi-byte character (lets assume that every `?` is a 2-byte
  36         // character) and `+` is a newline, the first value of `$i` is `0` and
  37         // the last one is `4` (because there are 5 characters). Bytes `$str[0]`
  38         // and `$str[1]` are the first character, `$str[2]` and `$str[3]` are
  39         // the second one and `$str[4]` is going to be the first byte of the
  40         // third character. The fourth and the last one (which is actually a new
  41         // line) aren't going to be processed at all.
  42         for ($i = 0, $len = /*overload*/mb_strlen($str, '8bit'); $i < $len; ++$i) {
  43             if ($str[$i] === "\n") {
  44                 $lines[] = $i + 1;
  45             }
  46         }
  47         return $lines;
  48     }
  49
  50     /**
  51      * Computes the number of the line and column given an absolute position.
  52      *
  53      * @param array $lines The starting position of each line.
  54      * @param int   $pos   The absolute position
  55      *
  56      * @return void
  57      */
  58     public static function findLineNumberAndColumn($lines, $pos)
  59     {
  60         $line = 0;
  61         foreach ($lines as $lineNo => $lineStart) {
  62             if ($lineStart > $pos) {
  63                 break;
  64             }
  65             $line = $lineNo;
  66         }
  67         return array($line, $pos - $lines[$line]);
  68     }
  69
  70     /**
  71      * Runs the linting process.
  72      *
  73      * @param string $query The query to be checked.
  74      *
  75      * @return void
  76      */
  77     public static function lint($query)
  78     {
  79         // Disabling lint for huge queries to save some resources.
  80         if (/*overload*/mb_strlen($query) > 10000) {
  81             return array(
  82                 array(
  83                     'message' => __('Linting is disabled for this query because it exceeds the maximum length.'),
  84                     'fromLine' => 0,
  85                     'fromColumn' => 0,
  86                     'toLine' => 0,
  87                     'toColumn' => 0,
  88                     'severity' => 'warning',
  89                 )
  90             );
  91         }
  92
  93         /**
  94          * Lexer used for tokenizing the query.
  95          *
  96          * @var SqlParser\Lexer
  97          */
  98         $lexer = new SqlParser\Lexer($query);
  99
 100         /**
 101          * Parsed used for analysing the query.
 102          *
 103          * @var SqlParser\Parser
 104          */
 105         $parser = new SqlParser\Parser($lexer->list);
 106
 107         /**
 108          * Array containing all errors.
 109          *
 110          * @var array
 111          */
 112         $errors = SqlParser\Utils\Error::get(array($lexer, $parser));
 113
 114         /**
 115          * The response containing of all errors.
 116          *
 117          * @var array
 118          */
 119         $response = array();
 120
 121         /**
 122          * The starting position for each line.
 123          *
 124          * CodeMirror requires relative position to line, but the parser stores
 125          * only the absolute position of the character in string.
 126          *
 127          * @var array
 128          */
 129         $lines = static::getLines($query);
 130
 131         // Building the response.
 132         foreach ($errors as $idx => $error) {
 133
 134             // Starting position of the string that caused the error.
 135             list($fromLine, $fromColumn) = static::findLineNumberAndColumn(
 136                 $lines, $error[3]
 137             );
 138
 139             // Ending position of the string that caused the error.
 140             list($toLine, $toColumn) = static::findLineNumberAndColumn(
 141                 $lines, $error[3] + /*overload*/mb_strlen($error[2])
 142             );
 143
 144             // Building the response.
 145             $response[] = array(
 146                 'message' => sprintf(
 147                     __('%1$s (near <code>%2$s</code>)'),
 148                     $error[0], $error[2]
 149                 ),
 150                 'fromLine' => $fromLine,
 151                 'fromColumn' => $fromColumn,
 152                 'toLine' => $toLine,
 153                 'toColumn' => $toColumn,
 154                 'severity' => 'error',
 155             );
 156         }
 157
 158         // Sending back the answer.
 159         return $response;
 160     }
 161
 162 }