includes/Math.php

   1 <?php
   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         global $wgTexvc;
  13         $mf   = wfMsg( "math_failure" );
  14         $munk = wfMsg( "math_unknown_error" );
  15
  16         $fname = "renderMath";
  17
  18         $math = $wgUser->getOption("math");
  19         if( $math == 3 ) {
  20                 return ('$ '.wfEscapeHTML($tex).' $');
  21         }
  22
  23         $md5 = md5($tex);
  24         $md5_sql = mysql_escape_string(pack("H32", $md5));
  25         if ($math == 0) {
  26                 $sql = "SELECT math_outputhash FROM math WHERE math_inputhash = '$md5_sql'";
  27         } else {
  28                 $sql = "SELECT math_outputhash,math_html_conservativeness,math_html FROM math WHERE math_inputhash = '$md5_sql'";
  29         }
  30
  31         $res = wfQuery( $sql, DB_READ, $fname );
  32
  33         if( $rpage = wfFetchObject ( $res ) ) {
  34                 $outputhash = unpack( "H32md5", $rpage->math_outputhash . "                " );
  35                 $outputhash = $outputhash ['md5'];
  36                 if( file_exists( "$wgMathDirectory/$outputhash.png" ) ) {
  37                         if (($math == 0) || ($rpage->math_html == '') || (($math == 1) && ($rpage->math_html_conservativeness != 2)) || (($math == 4) && ($rpage->math_html_conservativeness == 0))) {
  38                                 return linkToMathImage ( $tex, $outputhash );
  39                         } else {
  40                                 return $rpage->math_html;
  41                         }
  42                 }
  43         }
  44
  45         $cmd = $wgTexvc." ".
  46                 escapeshellarg($wgTmpDirectory)." ".
  47                 escapeshellarg($wgMathDirectory)." ".
  48                 escapeshellarg($tex)." ".
  49                 escapeshellarg($wgInputEncoding);
  50         wfDebug( "TeX: $cmd" );
  51         $contents = `$cmd`;
  52
  53         if (strlen($contents) == 0) {
  54                 return "<b>".$mf." (".$munk."): ".wfEscapeHTML($tex)."</b>";
  55         }
  56
  57         $retval = substr ($contents, 0, 1);
  58         if (($retval == "C") || ($retval == "M") || ($retval == "L")) {
  59             if ($retval == "C")
  60                 $conservativeness = 2;
  61             else if ($retval == "M")
  62                 $conservativeness = 1;
  63             else
  64                 $conservativeness = 0;
  65             $outdata = substr ($contents, 33);
  66
  67             $i = strpos($outdata, "\000");
  68
  69             $outhtml = substr($outdata, 0, $i);
  70             $mathml = substr($outdata, $i+1);
  71
  72             $sql_html = "'".mysql_escape_string($outhtml)."'";
  73             $sql_mathml = "'".mysql_escape_string($mathml)."'";
  74         } else if (($retval == "c") || ($retval == "m") || ($retval == "l"))  {
  75             $outhtml = substr ($contents, 33);
  76             if ($retval == "c")
  77                 $conservativeness = 2;
  78             else if ($retval == "m")
  79                 $conservativeness = 1;
  80             else
  81                 $conservativeness = 0;
  82             $sql_html = "'".mysql_escape_string($outhtml)."'";
  83             $mathml = '';
  84             $sql_mathml = 'NULL';
  85         } else if ($retval == "X") {
  86             $outhtml = '';
  87             $mathml = substr ($contents, 33);
  88             $sql_html = 'NULL';
  89             $sql_mathml = "'".mysql_escape_string($mathml)."'";
  90             $conservativeness = 0;
  91         } else if ($retval == "+") {
  92             $outhtml = '';
  93             $mathml = '';
  94             $sql_html = 'NULL';
  95             $sql_mathml = 'NULL';
  96             $conservativeness = 0;
  97         } else {
  98             if ($retval == "E")
  99                 $errmsg = wfMsg( "math_lexing_error" );
 100             else if ($retval == "S")
 101                 $errmsg = wfMsg( "math_syntax_error" );
 102             else if ($retval == "F")
 103                 $errmsg = wfMsg( "math_unknown_function" );
 104             else
 105                 $errmsg = $munk;
 106             return "<h3>".$mf." (".$errmsg.substr($contents, 1)."): ".wfEscapeHTML($tex)."</h3>";
 107         }
 108
 109         $outmd5 = substr ($contents, 1, 32);
 110         if (!preg_match("/^[a-f0-9]{32}$/", $outmd5)) {
 111                 return "<b>".$mf." (".$munk."): ".wfEscapeHTML($tex)."</b>";
 112         }
 113
 114         if( !file_exists( "$wgMathDirectory/$outmd5.png" ) ) {
 115                 $errmsg = wfMsg( "math_image_error" );
 116                 return "<h3>$mf ($errmsg): " . wfEscapeHTML($tex) . "</h3>";
 117         }
 118
 119         $outmd5_sql = mysql_escape_string(pack("H32", $outmd5));
 120
 121         $sql = "REPLACE INTO math VALUES ('".$md5_sql."', '".$outmd5_sql."', ".$conservativeness.", ".$sql_html.", ".$sql_mathml.")";
 122
 123         $res = wfQuery( $sql, DB_READ, $fname );
 124         # we don't really care if it fails
 125
 126         if (($math == 0) || ($rpage->math_html == '') || (($math == 1) && ($conservativeness != 2)) || (($math == 4) && ($conservativeness == 0)))
 127             return linkToMathImage($tex, $outmd5);
 128         else
 129             return $outhtml;
 130 }
 131
 132 ?>