Current File : /www/varak.net/wiki.varak.net/includes/libs/CSSMin.php
<?php
/**
* Minification of CSS stylesheets.
*
* Copyright 2010 Wikimedia Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software distributed
* under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS
* OF ANY KIND, either express or implied. See the License for the
* specific language governing permissions and limitations under the License.
*
* @file
* @version 0.1.1 -- 2010-09-11
* @author Trevor Parscal <tparscal@wikimedia.org>
* @copyright Copyright 2010 Wikimedia Foundation
* @license Apache-2.0
*/
/**
* Transforms CSS data
*
* This class provides minification, URL remapping, URL extracting, and data-URL embedding.
*/
class CSSMin {
/** @var string Strip marker for comments. **/
const PLACEHOLDER = "\x7fPLACEHOLDER\x7f";
/**
* Internet Explorer data URI length limit. See encodeImageAsDataURI().
*/
const DATA_URI_SIZE_LIMIT = 32768;
const EMBED_REGEX = '\/\*\s*\@embed\s*\*\/';
const COMMENT_REGEX = '\/\*.*?\*\/';
/** @var string[] List of common image files extensions and MIME-types */
protected static $mimeTypes = [
'gif' => 'image/gif',
'jpe' => 'image/jpeg',
'jpeg' => 'image/jpeg',
'jpg' => 'image/jpeg',
'png' => 'image/png',
'tif' => 'image/tiff',
'tiff' => 'image/tiff',
'xbm' => 'image/x-xbitmap',
'svg' => 'image/svg+xml',
];
/**
* Get a list of local files referenced in a stylesheet (includes non-existent files).
*
* @param string $source CSS stylesheet source to process
* @param string $path File path where the source was read from
* @return string[] List of local file references
*/
public static function getLocalFileReferences( $source, $path ) {
$stripped = preg_replace( '/' . self::COMMENT_REGEX . '/s', '', $source );
$path = rtrim( $path, '/' ) . '/';
$files = [];
$rFlags = PREG_OFFSET_CAPTURE | PREG_SET_ORDER;
if ( preg_match_all( '/' . self::getUrlRegex() . '/', $stripped, $matches, $rFlags ) ) {
foreach ( $matches as $match ) {
self::processUrlMatch( $match, $rFlags );
$url = $match['file'][0];
// Skip fully-qualified and protocol-relative URLs and data URIs
if (
substr( $url, 0, 2 ) === '//' ||
parse_url( $url, PHP_URL_SCHEME )
) {
break;
}
// Strip trailing anchors - T115436
$anchor = strpos( $url, '#' );
if ( $anchor !== false ) {
$url = substr( $url, 0, $anchor );
// '#some-anchors' is not a file
if ( $url === '' ) {
break;
}
}
$files[] = $path . $url;
}
}
return $files;
}
/**
* Encode an image file as a data URI.
*
* If the image file has a suitable MIME type and size, encode it as a data URI, base64-encoded
* for binary files or just percent-encoded otherwise. Return false if the image type is
* unfamiliar or file exceeds the size limit.
*
* @param string $file Image file to encode.
* @param string|null $type File's MIME type or null. If null, CSSMin will
* try to autodetect the type.
* @param bool $ie8Compat By default, a data URI will only be produced if it can be made short
* enough to fit in Internet Explorer 8 (and earlier) URI length limit (32,768 bytes). Pass
* `false` to remove this limitation.
* @return string|false Image contents encoded as a data URI or false.
*/
public static function encodeImageAsDataURI( $file, $type = null, $ie8Compat = true ) {
// Fast-fail for files that definitely exceed the maximum data URI length
if ( $ie8Compat && filesize( $file ) >= self::DATA_URI_SIZE_LIMIT ) {
return false;
}
if ( $type === null ) {
$type = self::getMimeType( $file );
}
if ( !$type ) {
return false;
}
return self::encodeStringAsDataURI( file_get_contents( $file ), $type, $ie8Compat );
}
/**
* Encode file contents as a data URI with chosen MIME type.
*
* The URI will be base64-encoded for binary files or just percent-encoded otherwise.
*
* @since 1.25
*
* @param string $contents File contents to encode.
* @param string $type File's MIME type.
* @param bool $ie8Compat See encodeImageAsDataURI().
* @return string|false Image contents encoded as a data URI or false.
*/
public static function encodeStringAsDataURI( $contents, $type, $ie8Compat = true ) {
// Try #1: Non-encoded data URI
// Remove XML declaration, it's not needed with data URI usage
$contents = preg_replace( "/<\\?xml.*?\\?>/", '', $contents );
// The regular expression matches ASCII whitespace and printable characters.
if ( preg_match( '/^[\r\n\t\x20-\x7e]+$/', $contents ) ) {
// Do not base64-encode non-binary files (sane SVGs).
// (This often produces longer URLs, but they compress better, yielding a net smaller size.)
$encoded = rawurlencode( $contents );
// Unencode some things that don't need to be encoded, to make the encoding smaller
$encoded = strtr( $encoded, [
'%20' => ' ', // Unencode spaces
'%2F' => '/', // Unencode slashes
'%3A' => ':', // Unencode colons
'%3D' => '=', // Unencode equals signs
'%0A' => ' ', // Change newlines to spaces
'%0D' => ' ', // Change carriage returns to spaces
'%09' => ' ', // Change tabs to spaces
] );
// Consolidate runs of multiple spaces in a row
$encoded = preg_replace( '/ {2,}/', ' ', $encoded );
// Remove leading and trailing spaces
$encoded = preg_replace( '/^ | $/', '', $encoded );
$uri = 'data:' . $type . ',' . $encoded;
if ( !$ie8Compat || strlen( $uri ) < self::DATA_URI_SIZE_LIMIT ) {
return $uri;
}
}
// Try #2: Encoded data URI
$uri = 'data:' . $type . ';base64,' . base64_encode( $contents );
if ( !$ie8Compat || strlen( $uri ) < self::DATA_URI_SIZE_LIMIT ) {
return $uri;
}
// A data URI couldn't be produced
return false;
}
/**
* Serialize a string (escape and quote) for use as a CSS string value.
* https://drafts.csswg.org/cssom/#serialize-a-string
*
* @param string $value
* @return string
*/
public static function serializeStringValue( $value ) {
$value = strtr( $value, [ "\0" => "\u{FFFD}", '\\' => '\\\\', '"' => '\\"' ] );
$value = preg_replace_callback( '/[\x01-\x1f\x7f]/', function ( $match ) {
return '\\' . base_convert( ord( $match[0] ), 10, 16 ) . ' ';
}, $value );
return '"' . $value . '"';
}
/**
* @param string $file
* @return bool|string
*/
public static function getMimeType( $file ) {
// Infer the MIME-type from the file extension
$ext = strtolower( pathinfo( $file, PATHINFO_EXTENSION ) );
if ( isset( self::$mimeTypes[$ext] ) ) {
return self::$mimeTypes[$ext];
}
return mime_content_type( realpath( $file ) );
}
/**
* Build a CSS 'url()' value for the given URL, quoting parentheses (and other funny characters)
* and escaping quotes as necessary.
*
* See http://www.w3.org/TR/css-syntax-3/#consume-a-url-token
*
* @param string $url URL to process
* @return string 'url()' value, usually just `"url($url)"`, quoted/escaped if necessary
*/
public static function buildUrlValue( $url ) {
// The list below has been crafted to match URLs such as:
// scheme://user@domain:port/~user/fi%20le.png?query=yes&really=y+s
// data:image/png;base64,R0lGODlh/+==
if ( preg_match( '!^[\w\d:@/~.%+;,?&=-]+$!', $url ) ) {
return "url($url)";
} else {
return 'url("' . strtr( $url, [ '\\' => '\\\\', '"' => '\\"' ] ) . '")';
}
}
/**
* Remaps CSS URL paths and automatically embeds data URIs for CSS rules
* or url() values preceded by an / * @embed * / comment.
*
* @param string $source CSS data to remap
* @param string $local File path where the source was read from
* @param string $remote URL path to the file
* @param bool $embedData If false, never do any data URI embedding,
* even if / * @embed * / is found.
* @return string Remapped CSS data
*/
public static function remap( $source, $local, $remote, $embedData = true ) {
// High-level overview:
// * For each CSS rule in $source that includes at least one url() value:
// * Check for an @embed comment at the start indicating that all URIs should be embedded
// * For each url() value:
// * Check for an @embed comment directly preceding the value
// * If either @embed comment exists:
// * Embedding the URL as data: URI, if it's possible / allowed
// * Otherwise remap the URL to work in generated stylesheets
// Guard against trailing slashes, because "some/remote/../foo.png"
// resolves to "some/remote/foo.png" on (some?) clients (T29052).
if ( substr( $remote, -1 ) == '/' ) {
$remote = substr( $remote, 0, -1 );
}
// Disallow U+007F DELETE, which is illegal anyway, and which
// we use for comment placeholders.
$source = str_replace( "\x7f", "?", $source );
// Replace all comments by a placeholder so they will not interfere with the remapping.
// Warning: This will also catch on anything looking like the start of a comment between
// quotation marks (e.g. "foo /* bar").
$comments = [];
$pattern = '/(?!' . self::EMBED_REGEX . ')(' . self::COMMENT_REGEX . ')/s';
$source = preg_replace_callback(
$pattern,
function ( $match ) use ( &$comments ) {
$comments[] = $match[ 0 ];
return CSSMin::PLACEHOLDER . ( count( $comments ) - 1 ) . 'x';
},
$source
);
// Note: This will not correctly handle cases where ';', '{' or '}'
// appears in the rule itself, e.g. in a quoted string. You are advised
// not to use such characters in file names. We also match start/end of
// the string to be consistent in edge-cases ('@import url(…)').
$pattern = '/(?:^|[;{])\K[^;{}]*' . self::getUrlRegex() . '[^;}]*(?=[;}]|$)/';
$source = preg_replace_callback(
$pattern,
function ( $matchOuter ) use ( $local, $remote, $embedData ) {
$rule = $matchOuter[0];
// Check for global @embed comment and remove it. Allow other comments to be present
// before @embed (they have been replaced with placeholders at this point).
$embedAll = false;
$rule = preg_replace(
'/^((?:\s+|' .
CSSMin::PLACEHOLDER .
'(\d+)x)*)' .
CSSMin::EMBED_REGEX .
'\s*/',
'$1',
$rule,
1,
$embedAll
);
// Build two versions of current rule: with remapped URLs
// and with embedded data: URIs (where possible).
$pattern = '/(?P<embed>' . CSSMin::EMBED_REGEX . '\s*|)' . self::getUrlRegex() . '/';
$ruleWithRemapped = preg_replace_callback(
$pattern,
function ( $match ) use ( $local, $remote ) {
self::processUrlMatch( $match );
$remapped = CSSMin::remapOne( $match['file'], $match['query'], $local, $remote, false );
return CSSMin::buildUrlValue( $remapped );
},
$rule
);
if ( $embedData ) {
// Remember the occurring MIME types to avoid fallbacks when embedding some files.
$mimeTypes = [];
$ruleWithEmbedded = preg_replace_callback(
$pattern,
function ( $match ) use ( $embedAll, $local, $remote, &$mimeTypes ) {
self::processUrlMatch( $match );
$embed = $embedAll || $match['embed'];
$embedded = CSSMin::remapOne(
$match['file'],
$match['query'],
$local,
$remote,
$embed
);
$url = $match['file'] . $match['query'];
$file = "{$local}/{$match['file']}";
if (
!self::isRemoteUrl( $url ) && !self::isLocalUrl( $url )
&& file_exists( $file )
) {
$mimeTypes[ CSSMin::getMimeType( $file ) ] = true;
}
return CSSMin::buildUrlValue( $embedded );
},
$rule
);
// Are all referenced images SVGs?
$needsEmbedFallback = $mimeTypes !== [ 'image/svg+xml' => true ];
}
if ( !$embedData || $ruleWithEmbedded === $ruleWithRemapped ) {
// We're not embedding anything, or we tried to but the file is not embeddable
return $ruleWithRemapped;
} elseif ( $embedData && $needsEmbedFallback ) {
// Build 2 CSS properties; one which uses a data URI in place of the @embed comment, and
// the other with a remapped and versioned URL with an Internet Explorer 6 and 7 hack
// making it ignored in all browsers that support data URIs
return "$ruleWithEmbedded;$ruleWithRemapped!ie";
} else {
// Look ma, no fallbacks! This is for files which IE 6 and 7 don't support anyway: SVG.
return $ruleWithEmbedded;
}
}, $source );
// Re-insert comments
$pattern = '/' . self::PLACEHOLDER . '(\d+)x/';
$source = preg_replace_callback( $pattern, function ( $match ) use ( &$comments ) {
return $comments[ $match[1] ];
}, $source );
return $source;
}
/**
* Is this CSS rule referencing a remote URL?
*
* @param string $maybeUrl
* @return bool
*/
protected static function isRemoteUrl( $maybeUrl ) {
if ( substr( $maybeUrl, 0, 2 ) === '//' || parse_url( $maybeUrl, PHP_URL_SCHEME ) ) {
return true;
}
return false;
}
/**
* Is this CSS rule referencing a local URL?
*
* @param string $maybeUrl
* @return bool
*/
protected static function isLocalUrl( $maybeUrl ) {
return isset( $maybeUrl[1] ) && $maybeUrl[0] === '/' && $maybeUrl[1] !== '/';
}
/**
* @codeCoverageIgnore
*/
private static function getUrlRegex() {
static $urlRegex;
if ( $urlRegex === null ) {
// Match these three variants separately to avoid broken urls when
// e.g. a double quoted url contains a parenthesis, or when a
// single quoted url contains a double quote, etc.
// FIXME: Simplify now we only support PHP 7.0.0+
// Note: PCRE doesn't support multiple capture groups with the same name by default.
// - PCRE 6.7 introduced the "J" modifier (PCRE_INFO_JCHANGED for PCRE_DUPNAMES).
// https://secure.php.net/manual/en/reference.pcre.pattern.modifiers.php
// However this isn't useful since it just ignores all but the first one.
// Also, while the modifier was introduced in PCRE 6.7 (PHP 5.2+) it was
// not exposed to public preg_* functions until PHP 5.6.0.
// - PCRE 8.36 fixed this to work as expected (e.g. merge conceptually to
// only return the one matched in the part that actually matched).
// However MediaWiki supports 5.5.9, which has PCRE 8.32
// Per https://secure.php.net/manual/en/pcre.installation.php:
// - PCRE 8.32 (PHP 5.5.0)
// - PCRE 8.34 (PHP 5.5.10, PHP 5.6.0)
// - PCRE 8.37 (PHP 5.5.26, PHP 5.6.9, PHP 7.0.0)
// Workaround by using different groups and merge via processUrlMatch().
// - Using string concatenation for class constant or member assignments
// is only supported in PHP 5.6. Use a getter method for now.
$urlRegex = '(' .
// Unquoted url
'url\(\s*(?P<file0>[^\s\'"][^\?\)]+?)(?P<query0>\?[^\)]*?|)\s*\)' .
// Single quoted url
'|url\(\s*\'(?P<file1>[^\?\']+?)(?P<query1>\?[^\']*?|)\'\s*\)' .
// Double quoted url
'|url\(\s*"(?P<file2>[^\?"]+?)(?P<query2>\?[^"]*?|)"\s*\)' .
')';
}
return $urlRegex;
}
private static function processUrlMatch( array &$match, $flags = 0 ) {
if ( $flags & PREG_SET_ORDER ) {
// preg_match_all with PREG_SET_ORDER will return each group in each
// match array, and if it didn't match, instead of the sub array
// being an empty array it is `[ '', -1 ]`...
if ( isset( $match['file0'] ) && $match['file0'][1] !== -1 ) {
$match['file'] = $match['file0'];
$match['query'] = $match['query0'];
} elseif ( isset( $match['file1'] ) && $match['file1'][1] !== -1 ) {
$match['file'] = $match['file1'];
$match['query'] = $match['query1'];
} else {
if ( !isset( $match['file2'] ) || $match['file2'][1] === -1 ) {
throw new Exception( 'URL must be non-empty' );
}
$match['file'] = $match['file2'];
$match['query'] = $match['query2'];
}
} else {
if ( isset( $match['file0'] ) && $match['file0'] !== '' ) {
$match['file'] = $match['file0'];
$match['query'] = $match['query0'];
} elseif ( isset( $match['file1'] ) && $match['file1'] !== '' ) {
$match['file'] = $match['file1'];
$match['query'] = $match['query1'];
} else {
if ( !isset( $match['file2'] ) || $match['file2'] === '' ) {
throw new Exception( 'URL must be non-empty' );
}
$match['file'] = $match['file2'];
$match['query'] = $match['query2'];
}
}
}
/**
* Remap or embed a CSS URL path.
*
* @param string $file URL to remap/embed
* @param string $query
* @param string $local File path where the source was read from
* @param string $remote URL path to the file
* @param bool $embed Whether to do any data URI embedding
* @return string Remapped/embedded URL data
*/
public static function remapOne( $file, $query, $local, $remote, $embed ) {
// The full URL possibly with query, as passed to the 'url()' value in CSS
$url = $file . $query;
// Expand local URLs with absolute paths like /w/index.php to possibly protocol-relative URL, if
// wfExpandUrl() is available. (This will not be the case if we're running outside of MW.)
if ( self::isLocalUrl( $url ) && function_exists( 'wfExpandUrl' ) ) {
return wfExpandUrl( $url, PROTO_RELATIVE );
}
// Pass thru fully-qualified and protocol-relative URLs and data URIs, as well as local URLs if
// we can't expand them.
// Also skips anchors or the rare `behavior` property specifying application's default behavior
if (
self::isRemoteUrl( $url ) ||
self::isLocalUrl( $url ) ||
substr( $url, 0, 1 ) === '#'
) {
return $url;
}
if ( $local === false ) {
// Assume that all paths are relative to $remote, and make them absolute
$url = $remote . '/' . $url;
} else {
// We drop the query part here and instead make the path relative to $remote
$url = "{$remote}/{$file}";
// Path to the actual file on the filesystem
$localFile = "{$local}/{$file}";
if ( file_exists( $localFile ) ) {
if ( $embed ) {
$data = self::encodeImageAsDataURI( $localFile );
if ( $data !== false ) {
return $data;
}
}
if ( class_exists( OutputPage::class ) ) {
$url = OutputPage::transformFilePath( $remote, $local, $file );
} else {
// Add version parameter as the first five hex digits
// of the MD5 hash of the file's contents.
$url .= '?' . substr( md5_file( $localFile ), 0, 5 );
}
}
// If any of these conditions failed (file missing, we don't want to embed it
// or it's not embeddable), return the URL (possibly with ?timestamp part)
}
if ( function_exists( 'wfRemoveDotSegments' ) ) {
$url = wfRemoveDotSegments( $url );
}
return $url;
}
/**
* Removes whitespace from CSS data
*
* @param string $css CSS data to minify
* @return string Minified CSS data
*/
public static function minify( $css ) {
return trim(
str_replace(
[ '; ', ': ', ' {', '{ ', ', ', '} ', ';}', '( ', ' )', '[ ', ' ]' ],
[ ';', ':', '{', '{', ',', '}', '}', '(', ')', '[', ']' ],
preg_replace( [ '/\s+/', '/\/\*.*?\*\//s' ], [ ' ', '' ], $css )
)
);
}
}
Mini Shell