* which when base64 encoded will result in a 1/3 increase in size.
*/
const EMBED_SIZE_LIMIT = 24576;
- const URL_REGEX = 'url\(\s*[\'"]?(?P<file>[^\?\)\'"]*)(?P<query>\??[^\)\'"]*)[\'"]?\s*\)';
+ const URL_REGEX = 'url\(\s*[\'"]?(?P<file>[^\?\)\'"]*?)(?P<query>\?[^\)\'"]*?|)[\'"]?\s*\)';
+ const EMBED_REGEX = '\/\*\s*\@embed\s*\*\/';
/* Protected Static Members */
}
/**
- * Remaps CSS URL paths and automatically embeds data URIs for URL rules
- * preceded by an /* @embed * / comment
+ * 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
* @return string Remapped CSS data
*/
public static function remap( $source, $local, $remote, $embedData = true ) {
- $pattern = '/((?P<embed>\s*\/\*\s*\@embed\s*\*\/)(?P<pre>[^\;\}]*))?' .
- self::URL_REGEX . '(?P<post>[^;]*)[\;]?/';
- $offset = 0;
- while ( preg_match( $pattern, $source, $match, PREG_OFFSET_CAPTURE, $offset ) ) {
- // Skip fully-qualified URLs and data URIs
- $urlScheme = parse_url( $match['file'][0], PHP_URL_SCHEME );
- if ( $urlScheme ) {
- // Move the offset to the end of the match, leaving it alone
- $offset = $match[0][1] + strlen( $match[0][0] );
- continue;
- }
- // URLs with absolute paths like /w/index.php need to be expanded
- // to absolute URLs but otherwise left alone
- if ( $match['file'][0] !== '' && $match['file'][0][0] === '/' ) {
- // Replace the file path with an expanded (possibly protocol-relative) URL
- // ...but only if wfExpandUrl() is even available.
- // This will not be the case if we're running outside of MW
- $lengthIncrease = 0;
- if ( function_exists( 'wfExpandUrl' ) ) {
- $expanded = wfExpandUrl( $match['file'][0], PROTO_RELATIVE );
- $origLength = strlen( $match['file'][0] );
- $lengthIncrease = strlen( $expanded ) - $origLength;
- $source = substr_replace( $source, $expanded,
- $match['file'][1], $origLength
- );
- }
- // Move the offset to the end of the match, leaving it alone
- $offset = $match[0][1] + strlen( $match[0][0] ) + $lengthIncrease;
- continue;
+ // 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 (bug 27052).
+ if ( substr( $remote, -1 ) == '/' ) {
+ $remote = substr( $remote, 0, -1 );
+ }
+
+ // 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(…)').
+ $pattern = '/(?:^|[;{])\K[^;{}]*' . CSSMin::URL_REGEX . '[^;}]*(?=[;}]|$)/';
+ return preg_replace_callback( $pattern, function ( $matchOuter ) use ( $local, $remote, $embedData ) {
+ $rule = $matchOuter[0];
+
+ // Check for global @embed comment and remove it
+ $embedAll = false;
+ $rule = preg_replace( '/^(\s*)' . 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*|)' . CSSMin::URL_REGEX . '/';
+
+ $ruleWithRemapped = preg_replace_callback( $pattern, function ( $match ) use ( $local, $remote ) {
+ $remapped = CSSMin::remapOne( $match['file'], $match['query'], $local, $remote, false );
+ return "url({$remapped})";
+ }, $rule );
+
+ if ( $embedData ) {
+ $ruleWithEmbedded = preg_replace_callback( $pattern, function ( $match ) use ( $embedAll, $local, $remote ) {
+ $embed = $embedAll || $match['embed'];
+ $embedded = CSSMin::remapOne( $match['file'], $match['query'], $local, $remote, $embed );
+ return "url({$embedded})";
+ }, $rule );
}
- // Guard against double slashes, because "some/remote/../foo.png"
- // resolves to "some/remote/foo.png" on (some?) clients (bug 27052).
- if ( substr( $remote, -1 ) == '/' ) {
- $remote = substr( $remote, 0, -1 );
+ if ( $embedData && $ruleWithEmbedded !== $ruleWithRemapped ) {
+ // Build 2 CSS properties; one which uses a base64 encoded data URI in place
+ // of the @embed comment to try and retain line-number integrity, and the
+ // other with a remapped an versioned URL and an Internet Explorer hack
+ // making it ignored in all browsers that support data URIs
+ return "$ruleWithEmbedded;$ruleWithRemapped!ie";
+ } else {
+ // No reason to repeat twice
+ return $ruleWithRemapped;
}
+ }, $source );
- // Shortcuts
- $embed = $match['embed'][0];
- $pre = $match['pre'][0];
- $post = $match['post'][0];
- $query = $match['query'][0];
- $url = "{$remote}/{$match['file'][0]}";
- $file = "{$local}/{$match['file'][0]}";
+ return $source;
+ }
- $replacement = false;
+ /**
+ * 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;
+
+ // Skip fully-qualified and protocol-relative URLs and data URIs
+ $urlScheme = substr( $url, 0, 2 ) === '//' || parse_url( $url, PHP_URL_SCHEME );
+ if ( $urlScheme ) {
+ return $url;
+ }
+
+ // URLs with absolute paths like /w/index.php need to be expanded
+ // to absolute URLs but otherwise left alone
+ if ( $url !== '' && $url[0] === '/' ) {
+ // Replace the file path with an expanded (possibly protocol-relative) URL
+ // ...but only if wfExpandUrl() is even available.
+ // This will not be the case if we're running outside of MW
+ if ( function_exists( 'wfExpandUrl' ) ) {
+ return wfExpandUrl( $url, PROTO_RELATIVE );
+ } else {
+ return $url;
+ }
+ }
- if ( $local !== false && file_exists( $file ) ) {
+ if ( $local === false ) {
+ // Assume that all paths are relative to $remote, and make them absolute
+ return $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 ) ) {
// Add version parameter as a time-stamp in ISO 8601 format,
// using Z for the timezone, meaning GMT
- $url .= '?' . gmdate( 'Y-m-d\TH:i:s\Z', round( filemtime( $file ), -2 ) );
- // Embedding requires a bit of extra processing, so let's skip that if we can
- if ( $embedData && $embed && $match['embed'][1] > 0 ) {
- $data = self::encodeImageAsDataURI( $file );
+ $url .= '?' . gmdate( 'Y-m-d\TH:i:s\Z', round( filemtime( $localFile ), -2 ) );
+ if ( $embed ) {
+ $data = self::encodeImageAsDataURI( $localFile );
if ( $data !== false ) {
- // Build 2 CSS properties; one which uses a base64 encoded data URI in place
- // of the @embed comment to try and retain line-number integrity, and the
- // other with a remapped an versioned URL and an Internet Explorer hack
- // making it ignored in all browsers that support data URIs
- $replacement = "{$pre}url({$data}){$post};{$pre}url({$url}){$post}!ie;";
+ return $data;
}
}
- if ( $replacement === false ) {
- // Assume that all paths are relative to $remote, and make them absolute
- $replacement = "{$embed}{$pre}url({$url}){$post};";
- }
- } elseif ( $local === false ) {
- // Assume that all paths are relative to $remote, and make them absolute
- $replacement = "{$embed}{$pre}url({$url}{$query}){$post};";
- }
- if ( $replacement !== false ) {
- // Perform replacement on the source
- $source = substr_replace(
- $source, $replacement, $match[0][1], strlen( $match[0][0] )
- );
- // Move the offset to the end of the replacement in the source
- $offset = $match[0][1] + strlen( $replacement );
- continue;
}
- // Move the offset to the end of the match, leaving it alone
- $offset = $match[0][1] + strlen( $match[0][0] );
+ // 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)
+ return $url;
}
- return $source;
}
/**