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         # Ensure that the temp and output directories are available before continuing...
  46         if( !file_exists( $wgMathDirectory ) ) {
  47                 if( !@mkdir( $wgMathDirectory ) ) {
  48                         return "<b>$mf (" . wfMsg( "math_bad_output" ) . ")</b>";
  49                 }
  50         } elseif( !is_dir( $wgMathDirectory ) || !is_writable( $wgMathDirectory ) ) {
  51                 return "<b>$mf (" . wfMsg( "math_bad_output" ) . ")</b>";
  52         }
  53         if( !file_exists( $wgTmpDirectory ) ) {
  54                 if( !@mkdir( $wgTmpDirectory ) ) {
  55                         return "<b>$mf (" . wfMsg( "math_bad_tmpdir" ) . ")</b>";
  56                 }
  57         } elseif( !is_dir( $wgTmpDirectory ) || !is_writable( $wgTmpDirectory ) ) {
  58                 return "<b>$mf (" . wfMsg( "math_bad_tmpdir" ) . ")</b>";
  59         }
  60
  61         if( !is_executable( $wgTexvc ) ) {
  62                 return "<b>$mf (" . wfMsg( "math_notexvc" ) . ")</b>";
  63         }
  64         $cmd = $wgTexvc." ".
  65                 escapeshellarg($wgTmpDirectory)." ".
  66                 escapeshellarg($wgMathDirectory)." ".
  67                 escapeshellarg($tex)." ".
  68                 escapeshellarg($wgInputEncoding);
  69         wfDebug( "TeX: $cmd" );
  70         $contents = `$cmd`;
  71
  72         if (strlen($contents) == 0) {
  73                 return "<b>".$mf." (".$munk."): ".wfEscapeHTML($tex)."</b>";
  74         }
  75
  76         $retval = substr ($contents, 0, 1);
  77         if (($retval == "C") || ($retval == "M") || ($retval == "L")) {
  78             if ($retval == "C")
  79                 $conservativeness = 2;
  80             else if ($retval == "M")
  81                 $conservativeness = 1;
  82             else
  83                 $conservativeness = 0;
  84             $outdata = substr ($contents, 33);
  85
  86             $i = strpos($outdata, "\000");
  87
  88             $outhtml = substr($outdata, 0, $i);
  89             $mathml = substr($outdata, $i+1);
  90
  91             $sql_html = "'".mysql_escape_string($outhtml)."'";
  92             $sql_mathml = "'".mysql_escape_string($mathml)."'";
  93         } else if (($retval == "c") || ($retval == "m") || ($retval == "l"))  {
  94             $outhtml = substr ($contents, 33);
  95             if ($retval == "c")
  96                 $conservativeness = 2;
  97             else if ($retval == "m")
  98                 $conservativeness = 1;
  99             else
 100                 $conservativeness = 0;
 101             $sql_html = "'".mysql_escape_string($outhtml)."'";
 102             $mathml = '';
 103             $sql_mathml = 'NULL';
 104         } else if ($retval == "X") {
 105             $outhtml = '';
 106             $mathml = substr ($contents, 33);
 107             $sql_html = 'NULL';
 108             $sql_mathml = "'".mysql_escape_string($mathml)."'";
 109             $conservativeness = 0;
 110         } else if ($retval == "+") {
 111             $outhtml = '';
 112             $mathml = '';
 113             $sql_html = 'NULL';
 114             $sql_mathml = 'NULL';
 115             $conservativeness = 0;
 116         } else {
 117             if ($retval == "E")
 118                 $errmsg = wfMsg( "math_lexing_error" );
 119             else if ($retval == "S")
 120                 $errmsg = wfMsg( "math_syntax_error" );
 121             else if ($retval == "F")
 122                 $errmsg = wfMsg( "math_unknown_function" );
 123             else
 124                 $errmsg = $munk;
 125             return "<h3>".$mf." (".$errmsg.substr($contents, 1)."): ".wfEscapeHTML($tex)."</h3>";
 126         }
 127
 128         $outmd5 = substr ($contents, 1, 32);
 129         if (!preg_match("/^[a-f0-9]{32}$/", $outmd5)) {
 130                 return "<b>".$mf." (".$munk."): ".wfEscapeHTML($tex)."</b>";
 131         }
 132
 133         if( !file_exists( "$wgMathDirectory/$outmd5.png" ) ) {
 134                 $errmsg = wfMsg( "math_image_error" );
 135                 return "<h3>$mf ($errmsg): " . wfEscapeHTML($tex) . "</h3>";
 136         }
 137
 138         $outmd5_sql = mysql_escape_string(pack("H32", $outmd5));
 139
 140         $sql = "REPLACE INTO math VALUES ('".$md5_sql."', '".$outmd5_sql."', ".$conservativeness.", ".$sql_html.", ".$sql_mathml.")";
 141
 142         $res = wfQuery( $sql, DB_READ, $fname );
 143         # we don't really care if it fails
 144
 145         if (($math == 0) || ($rpage->math_html == '') || (($math == 1) && ($conservativeness != 2)) || (($math == 4) && ($conservativeness == 0)))
 146             return linkToMathImage($tex, $outmd5);
 147         else
 148             return $outhtml;
 149 }
 150
 151 ?>