includes/Math.php

   1 <?
   2
   3 function linkToMathImage ( $tex, $outputhash )
   4 {
   5         global $wgMathPath;
   6         return "<img src=\"".$wgMathPath."/".$outputhash.".png\" alt=\"".wfEscapeHTML($tex)."\">";
   7 }
   8
   9 function renderMath( $tex )
  10 {
  11     global $wgUser, $wgMathDirectory, $wgTmpDirectory, $wgInputEncoding;
  12     $mf   = wfMsg( "math_failure" );
  13     $munk = wfMsg( "math_unknown_error" );
  14
  15     $fname = "renderMath";
  16
  17     $math = $wgUser->getOption("math");
  18     if ($math == 3)
  19         return ('$ '.wfEscapeHTML($tex).' $');
  20
  21     $md5 = md5($tex);
  22     $md5_sql = mysql_escape_string(pack("H32", $md5));
  23     if ($math == 0)
  24         $sql = "SELECT math_outputhash FROM math WHERE math_inputhash = '".$md5_sql."'";
  25     else
  26         $sql = "SELECT math_outputhash,math_html_conservativeness,math_html FROM math WHERE math_inputhash = '".$md5_sql."'";
  27
  28     $res = wfQuery( $sql, DB_READ, $fname );
  29
  30         if( $rpage = wfFetchObject ( $res ) ) {
  31                 $outputhash = unpack( "H32md5", $rpage->math_outputhash . "                " );
  32                 $outputhash = $outputhash ['md5'];
  33                 if( file_exists( "$wgMathDirectory/$outputhash.png" ) ) {
  34                         if (($math == 0) || ($rpage->math_html == '') || (($math == 1) && ($rpage->math_html_conservativeness != 2)) || (($math == 4) && ($rpage->math_html_conservativeness == 0)))
  35                             return linkToMathImage ( $tex, $outputhash );
  36                         else
  37                         return $rpage->math_html;
  38                 }
  39         }
  40
  41         $cmd = "./math/texvc ".escapeshellarg($wgTmpDirectory)." ".
  42                       escapeshellarg($wgMathDirectory)." ".escapeshellarg($tex)." ".escapeshellarg($wgInputEncoding);
  43         $contents = `$cmd`;
  44
  45         if (strlen($contents) == 0)
  46             return "<b>".$mf." (".$munk."): ".wfEscapeHTML($tex)."</b>";
  47         $retval = substr ($contents, 0, 1);
  48         if (($retval == "C") || ($retval == "M") || ($retval == "L")) {
  49             if ($retval == "C")
  50                 $conservativeness = 2;
  51             else if ($retval == "M")
  52                 $conservativeness = 1;
  53             else
  54                 $conservativeness = 0;
  55             $outdata = substr ($contents, 33);
  56
  57             $i = strpos($outdata, "\000");
  58
  59             $outhtml = substr($outdata, 0, $i);
  60             $mathml = substr($outdata, $i+1);
  61
  62             $sql_html = "'".mysql_escape_string($outhtml)."'";
  63             $sql_mathml = "'".mysql_escape_string($mathml)."'";
  64         } else if (($retval == "c") || ($retval == "m") || ($retval == "l"))  {
  65             $outhtml = substr ($contents, 33);
  66             if ($retval == "c")
  67                 $conservativeness = 2;
  68             else if ($retval == "m")
  69                 $conservativeness = 1;
  70             else
  71                 $conservativeness = 0;
  72             $sql_html = "'".mysql_escape_string($outhtml)."'";
  73             $mathml = '';
  74             $sql_mathml = 'NULL';
  75         } else if ($retval == "X") {
  76             $outhtml = '';
  77             $mathml = substr ($contents, 33);
  78             $sql_html = 'NULL';
  79             $sql_mathml = "'".mysql_escape_string($mathml)."'";
  80             $conservativeness = 0;
  81         } else if ($retval == "+") {
  82             $outhtml = '';
  83             $mathml = '';
  84             $sql_html = 'NULL';
  85             $sql_mathml = 'NULL';
  86             $conservativeness = 0;
  87         } else {
  88             if ($retval == "E")
  89                 $errmsg = wfMsg( "math_lexing_error" );
  90             else if ($retval == "S")
  91                 $errmsg = wfMsg( "math_syntax_error" );
  92             else if ($retval == "F")
  93                 $errmsg = wfMsg( "math_unknown_function" );
  94             else
  95                 $errmsg = $munk;
  96             return "<h3>".$mf." (".$errmsg.substr($contents, 1)."): ".wfEscapeHTML($tex)."</h3>";
  97         }
  98
  99         $outmd5 = substr ($contents, 1, 32);
 100         if (!preg_match("/^[a-f0-9]{32}$/", $outmd5))
 101             return "<b>".$mf." (".$munk."): ".wfEscapeHTML($tex)."</b>";
 102
 103         $outmd5_sql = mysql_escape_string(pack("H32", $outmd5));
 104
 105         $sql = "REPLACE INTO math VALUES ('".$md5_sql."', '".$outmd5_sql."', ".$conservativeness.", ".$sql_html.", ".$sql_mathml.")";
 106
 107         $res = wfQuery( $sql, DB_READ, $fname );
 108         # we don't really care if it fails
 109
 110         if (($math == 0) || ($rpage->math_html == '') || (($math == 1) && ($conservativeness != 2)) || (($math == 4) && ($conservativeness == 0)))
 111             return linkToMathImage($tex, $outmd5);
 112         else
 113             return $outhtml;
 114 }
 115
 116 ?>