mediawiki-extensions-Math/MathTexvc.php
vishnu 0ab1280d6b Fix depreciation warnings in FileBackend construction
Added wikiId and lockManager was changed to an object
Bug: 58615

Change-Id: Id3bdc7e6bc3951db4753553da03193783f0bd7c8
2013-12-27 23:27:32 +05:30

367 lines
10 KiB
PHP

<?php
/**
* MediaWiki math extension
*
* (c) 2002-2012 Tomasz Wegrzanowski, Brion Vibber, Moritz Schubotz, and other MediaWiki contributors
* GPLv2 license; info in main package.
*
* Contains the driver function for the texvc program
* @file
*/
/**
* Takes LaTeX fragments, sends them to a helper program (texvc) for rendering
* to rasterized PNG and HTML and MathML approximations. An appropriate
* rendering form is picked and returned.
*
* @author Tomasz Wegrzanowski
* @author Brion Vibber
* @author Moritz Schubotz
*/
class MathTexvc extends MathRenderer {
const CONSERVATIVE = 2;
const MODERATE = 1;
const LIBERAL = 0;
const MW_TEXVC_SUCCESS = -1;
/**
* Renders TeX using texvc
*
* @return string rendered TeK
*/
public function render() {
if ( !$this->readCache() ) { // cache miss
$result = $this->callTexvc();
if ( $result != self::MW_TEXVC_SUCCESS ) {
return $result;
}
}
return $this->doHTMLRender();
}
/**
* Gets path to store hashes in
*
* @return string Storage directory
*/
public function getHashPath() {
$path = $this->getBackend()->getRootStoragePath() .
'/math-render/' . $this->getHashSubPath();
wfDebugLog("Math", "TeX: getHashPath, hash is: {$this->getHash()}, path is: $path\n" );
return $path;
}
/**
* Gets relative directory for this specific hash
*
* @return string Relative directory
*/
public function getHashSubPath() {
return substr( $this->getHash(), 0, 1 )
. '/' . substr( $this->getHash(), 1, 1 )
. '/' . substr( $this->getHash(), 2, 1 );
}
/**
* Gets URL for math image
*
* @return string image URL
*/
public function getMathImageUrl() {
global $wgMathPath;
$dir = $this->getHashSubPath();
return "$wgMathPath/$dir/{$this->getHash()}.png";
}
/**
* Gets img tag for math image
*
* @return string img HTML
*/
public function getMathImageHTML() {
$url = $this->getMathImageUrl();
return Xml::element( 'img',
$this->getAttributes(
'img',
array(
'class' => 'tex',
'alt' => $this->getTex(),
),
array(
'src' => $url
)
)
);
}
/**
* Converts an error returned by texvc to a localized exception
*
* @param string $texvcResult error result returned by texvc
*/
public function convertTexvcError( $texvcResult ) {
$texvcStatus = substr( $texvcResult, 0, 1 );
$errDetails = htmlspecialchars( substr( $texvcResult, 1 ) );
switch( $texvcStatus ) {
case 'E':
$errMsg = $this->getError( 'math_lexing_error' );
break;
case 'S':
$errMsg = $this->getError( 'math_syntax_error' );
break;
case 'F':
$errMsg = $this->getError( 'math_unknown_function', $errDetails );
break;
default:
$errMsg = $this->getError( 'math_unknown_error' );
}
return $errMsg;
}
/**
* Does the actual call to texvc
*
* @return int|string MW_TEXVC_SUCCESS or error string
*/
public function callTexvc() {
global $wgTexvc, $wgTexvcBackgroundColor, $wgUseSquid, $wgMathCheckFiles, $wgHooks;
wfProfileIn( __METHOD__ );
$tmpDir = wfTempDir();
if ( !is_executable( $wgTexvc ) ) {
wfDebugLog( 'texvc', "$wgTexvc does not exist or is not executable." );
wfProfileOut( __METHOD__ );
return $this->getError( 'math_notexvc' );
}
$escapedTmpDir = wfEscapeShellArg( $tmpDir );
$cmd = $wgTexvc . ' ' .
$escapedTmpDir . ' ' .
$escapedTmpDir . ' ' .
wfEscapeShellArg( $this->getTex() ) . ' ' .
wfEscapeShellArg( 'UTF-8' ) . ' ' .
wfEscapeShellArg( $wgTexvcBackgroundColor );
if ( wfIsWindows() ) {
# Invoke it within cygwin sh, because texvc expects sh features in its default shell
$cmd = 'sh -c ' . wfEscapeShellArg( $cmd );
}
wfDebugLog( 'Math', "TeX: $cmd\n" );
wfDebugLog( 'texvc', "Executing '$cmd'." );
$retval = null;
$contents = wfShellExec( $cmd, $retval );
wfDebugLog( 'Math', "TeX output:\n $contents\n---\n" );
if ( strlen( $contents ) == 0 ) {
if ( !file_exists( $tmpDir ) || !is_writable( $tmpDir ) ) {
wfDebugLog( 'texvc', "TeX output directory $tmpDir is missing or not writable" );
wfProfileOut( __METHOD__ );
return $this->getError( 'math_bad_tmpdir' );
} else {
wfDebugLog( 'texvc', "TeX command '$cmd' returned no output and status code $retval." );
wfProfileOut( __METHOD__ );
return $this->getError( 'math_unknown_error' );
}
}
$tempFsFile = new TempFSFile( "$tmpDir/{$this->getHash()}.png" );
$tempFsFile->autocollect(); // destroy file when $tempFsFile leaves scope
$retval = substr( $contents, 0, 1 );
$errmsg = '';
if ( ( $retval == 'C' ) || ( $retval == 'M' ) || ( $retval == 'L' ) ) {
if ( $retval == 'C' ) {
$this->setConservativeness( self::CONSERVATIVE );
} elseif ( $retval == 'M' ) {
$this->setConservativeness( self::MODERATE );
} else {
$this->setConservativeness( self::LIBERAL );
}
$outdata = substr( $contents, 33 );
$i = strpos( $outdata, "\000" );
$this->setHtml( substr( $outdata, 0, $i ) );
$this->setMathml( substr( $outdata, $i + 1 ) );
} elseif ( ( $retval == 'c' ) || ( $retval == 'm' ) || ( $retval == 'l' ) ) {
$this->setHtml( substr( $contents, 33 ) );
if ( $retval == 'c' ) {
$this->setConservativeness( self::CONSERVATIVE ) ;
} elseif ( $retval == 'm' ) {
$this->setConservativeness( self::MODERATE );
} else {
$this->setConservativeness( self::LIBERAL );
}
$this->setMathml( null );
} elseif ( $retval == 'X' ) {
$this->setHtml( null );
$this->setMathml( substr( $contents, 33 ) );
$this->setConservativeness( self::LIBERAL );
} elseif ( $retval == '+' ) {
$this->setHtml( null );
$this->setMathml( null );
$this->setConservativeness( self::LIBERAL );
} else {
$errmsg = $this->convertTexvcError( $contents );
}
if ( !$errmsg ) {
$this->setHash( substr( $contents, 1, 32 ) );
}
wfRunHooks( 'MathAfterTexvc', array( &$this, &$errmsg ) );
if ( $errmsg ) {
wfProfileOut( __METHOD__ );
return $errmsg;
} elseif ( !preg_match( "/^[a-f0-9]{32}$/", $this->getHash() ) ) {
wfProfileOut( __METHOD__ );
return $this->getError( 'math_unknown_error' );
} elseif ( !file_exists( "$tmpDir/{$this->getHash()}.png" ) ) {
wfProfileOut( __METHOD__ );
return $this->getError( 'math_image_error' );
} elseif ( filesize( "$tmpDir/{$this->getHash()}.png" ) == 0 ) {
wfProfileOut( __METHOD__ );
return $this->getError( 'math_image_error' );
}
$hashpath = $this->getHashPath(); // final storage directory
$backend = $this->getBackend();
# Create any containers/directories as needed...
if ( !$backend->prepare( array( 'dir' => $hashpath ) )->isOK() ) {
wfProfileOut( __METHOD__ );
return $this->getError( 'math_output_error' );
}
// Store the file at the final storage path...
// Bug 56769: buffer the writes and do them at the end.
if ( !isset( $wgHooks['ParserAfterParse']['FlushMathBackend'] ) ) {
$backend->mathBufferedWrites = array();
$wgHooks['ParserAfterParse']['FlushMathBackend'] = function() use ( $backend ) {
global $wgHooks;
unset( $wgHooks['ParserAfterParse']['FlushMathBackend'] );
$backend->doQuickOperations( $backend->mathBufferedWrites );
unset( $backend->mathBufferedWrites );
};
}
$backend->mathBufferedWrites[] = array(
'op' => 'store',
'src' => "$tmpDir/{$this->getHash()}.png",
'dst' => "$hashpath/{$this->getHash()}.png",
'ref' => $tempFsFile // keep file alive
);
wfProfileOut( __METHOD__ );
return self::MW_TEXVC_SUCCESS;
}
/**
* Gets file backend
*
* @return FileBackend appropriate file backend
*/
public function getBackend() {
global $wgMathFileBackend, $wgMathDirectory;
if ( $wgMathFileBackend ) {
return FileBackendGroup::singleton()->get( $wgMathFileBackend );
} else {
static $backend = null;
if ( !$backend ) {
$backend = new FSFileBackend( array(
'name' => 'math-backend',
'wikiId' => wfWikiId(),
'lockManager' => new NullLockManager(array() ),
'containerPaths' => array( 'math-render' => $wgMathDirectory ),
'fileMode' => 0777
) );
}
return $backend;
}
}
/**
* Does the HTML rendering
*
* @return string HTML string
*/
public function doHTMLRender() {
if ( $this->getMode() == MW_MATH_MATHML && $this->getMathml() != '' ) {
return Xml::tags( 'math',
$this->getAttributes( 'math',
array( 'xmlns' => 'http://www.w3.org/1998/Math/MathML' ) ),
$this->mathml );
}
if ( ( $this->getMode() == MW_MATH_PNG ) || ( $this->getHtml() == '' ) ||
( ( $this->getMode() == MW_MATH_SIMPLE ) && ( $this->getConservativeness() != self::CONSERVATIVE ) ) ||
( ( $this->getMode() == MW_MATH_MODERN || $this->getMode() == MW_MATH_MATHML ) && ( $this->getConservativeness() == self::LIBERAL ) )
)
{
return $this->getMathImageHTML();
} else {
return Xml::tags( 'span',
$this->getAttributes( 'span',
array( 'class' => 'texhtml',
'dir' => 'ltr'
) ),
$this->getHtml()
);
}
}
/**
* Overrides base class. Writes to database, and if configured, squid.
*/
public function writeCache() {
global $wgUseSquid;
wfProfileIn( __METHOD__ );
// If cache hit, don't write anything.
if ( $this->isRecall() ) {
wfProfileOut( __METHOD__ );
return;
}
$this->writeToDatabase();
// If we're replacing an older version of the image, make sure it's current.
if ( $wgUseSquid ) {
$urls = array( $this->getMathImageUrl() );
$u = new SquidUpdate( $urls );
$u->doUpdate();
}
wfProfileOut( __METHOD__ );
}
/**
* Reads the rendering information from the database. If configured, checks whether files exist
*
* @return boolean true if retrieved, false otherwise
*/
public function readCache() {
global $wgMathCheckFiles;
wfProfileIn( __METHOD__ );
if ( $this->readFromDatabase() ) {
if ( !$wgMathCheckFiles ) {
// Short-circuit the file existence & migration checks
wfProfileOut( __METHOD__ );
return true;
}
$filename = $this->getHashPath() . "/{$this->getHash()}.png"; // final storage path
$backend = $this->getBackend();
if ( $backend->fileExists( array( 'src' => $filename ) ) ) {
if ( $backend->getFileSize( array( 'src' => $filename ) ) == 0 ) {
// Some horrible error corrupted stuff :(
$backend->quickDelete( array( 'src' => $filename ) );
} else {
wfProfileOut( __METHOD__ );
return true; // cache hit
}
}
}
wfProfileOut( __METHOD__ );
return false;
}
}