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-rw-r--r--includes/StringUtils.php301
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+<?php
+
+class StringUtils {
+ /**
+ * Perform an operation equivalent to
+ *
+ * preg_replace( "!$startDelim(.*?)$endDelim!", $replace, $subject );
+ *
+ * except that it's worst-case O(N) instead of O(N^2)
+ *
+ * Compared to delimiterReplace(), this implementation is fast but memory-
+ * hungry and inflexible. The memory requirements are such that I don't
+ * recommend using it on anything but guaranteed small chunks of text.
+ */
+ static function hungryDelimiterReplace( $startDelim, $endDelim, $replace, $subject ) {
+ $segments = explode( $startDelim, $subject );
+ $output = array_shift( $segments );
+ foreach ( $segments as $s ) {
+ $endDelimPos = strpos( $s, $endDelim );
+ if ( $endDelimPos === false ) {
+ $output .= $startDelim . $s;
+ } else {
+ $output .= $replace . substr( $s, $endDelimPos + strlen( $endDelim ) );
+ }
+ }
+ return $output;
+ }
+
+ /**
+ * Perform an operation equivalent to
+ *
+ * preg_replace_callback( "!$startDelim(.*)$endDelim!s$flags", $callback, $subject )
+ *
+ * This implementation is slower than hungryDelimiterReplace but uses far less
+ * memory. The delimiters are literal strings, not regular expressions.
+ *
+ * @param string $flags Regular expression flags
+ */
+ # If the start delimiter ends with an initial substring of the end delimiter,
+ # e.g. in the case of C-style comments, the behaviour differs from the model
+ # regex. In this implementation, the end must share no characters with the
+ # start, so e.g. /*/ is not considered to be both the start and end of a
+ # comment. /*/xy/*/ is considered to be a single comment with contents /xy/.
+ static function delimiterReplaceCallback( $startDelim, $endDelim, $callback, $subject, $flags = '' ) {
+ $inputPos = 0;
+ $outputPos = 0;
+ $output = '';
+ $foundStart = false;
+ $encStart = preg_quote( $startDelim, '!' );
+ $encEnd = preg_quote( $endDelim, '!' );
+ $strcmp = strpos( $flags, 'i' ) === false ? 'strcmp' : 'strcasecmp';
+ $endLength = strlen( $endDelim );
+ $m = array();
+
+ while ( $inputPos < strlen( $subject ) &&
+ preg_match( "!($encStart)|($encEnd)!S$flags", $subject, $m, PREG_OFFSET_CAPTURE, $inputPos ) )
+ {
+ $tokenOffset = $m[0][1];
+ if ( $m[1][0] != '' ) {
+ if ( $foundStart &&
+ $strcmp( $endDelim, substr( $subject, $tokenOffset, $endLength ) ) == 0 )
+ {
+ # An end match is present at the same location
+ $tokenType = 'end';
+ $tokenLength = $endLength;
+ } else {
+ $tokenType = 'start';
+ $tokenLength = strlen( $m[0][0] );
+ }
+ } elseif ( $m[2][0] != '' ) {
+ $tokenType = 'end';
+ $tokenLength = strlen( $m[0][0] );
+ } else {
+ throw new MWException( 'Invalid delimiter given to ' . __METHOD__ );
+ }
+
+ if ( $tokenType == 'start' ) {
+ $inputPos = $tokenOffset + $tokenLength;
+ # Only move the start position if we haven't already found a start
+ # This means that START START END matches outer pair
+ if ( !$foundStart ) {
+ # Found start
+ # Write out the non-matching section
+ $output .= substr( $subject, $outputPos, $tokenOffset - $outputPos );
+ $outputPos = $tokenOffset;
+ $contentPos = $inputPos;
+ $foundStart = true;
+ }
+ } elseif ( $tokenType == 'end' ) {
+ if ( $foundStart ) {
+ # Found match
+ $output .= call_user_func( $callback, array(
+ substr( $subject, $outputPos, $tokenOffset + $tokenLength - $outputPos ),
+ substr( $subject, $contentPos, $tokenOffset - $contentPos )
+ ));
+ $foundStart = false;
+ } else {
+ # Non-matching end, write it out
+ $output .= substr( $subject, $inputPos, $tokenOffset + $tokenLength - $outputPos );
+ }
+ $inputPos = $outputPos = $tokenOffset + $tokenLength;
+ } else {
+ throw new MWException( 'Invalid delimiter given to ' . __METHOD__ );
+ }
+ }
+ if ( $outputPos < strlen( $subject ) ) {
+ $output .= substr( $subject, $outputPos );
+ }
+ return $output;
+ }
+
+ /*
+ * Perform an operation equivalent to
+ *
+ * preg_replace( "!$startDelim(.*)$endDelim!$flags", $replace, $subject )
+ *
+ * @param string $startDelim Start delimiter regular expression
+ * @param string $endDelim End delimiter regular expression
+ * @param string $replace Replacement string. May contain $1, which will be
+ * replaced by the text between the delimiters
+ * @param string $subject String to search
+ * @return string The string with the matches replaced
+ */
+ static function delimiterReplace( $startDelim, $endDelim, $replace, $subject, $flags = '' ) {
+ $replacer = new RegexlikeReplacer( $replace );
+ return self::delimiterReplaceCallback( $startDelim, $endDelim,
+ $replacer->cb(), $subject, $flags );
+ }
+
+ /**
+ * More or less "markup-safe" explode()
+ * Ignores any instances of the separator inside <...>
+ * @param string $separator
+ * @param string $text
+ * @return array
+ */
+ static function explodeMarkup( $separator, $text ) {
+ $placeholder = "\x00";
+
+ // Remove placeholder instances
+ $text = str_replace( $placeholder, '', $text );
+
+ // Replace instances of the separator inside HTML-like tags with the placeholder
+ $replacer = new DoubleReplacer( $separator, $placeholder );
+ $cleaned = StringUtils::delimiterReplaceCallback( '<', '>', $replacer->cb(), $text );
+
+ // Explode, then put the replaced separators back in
+ $items = explode( $separator, $cleaned );
+ foreach( $items as $i => $str ) {
+ $items[$i] = str_replace( $placeholder, $separator, $str );
+ }
+
+ return $items;
+ }
+
+ /**
+ * Escape a string to make it suitable for inclusion in a preg_replace()
+ * replacement parameter.
+ *
+ * @param string $string
+ * @return string
+ */
+ static function escapeRegexReplacement( $string ) {
+ $string = str_replace( '\\', '\\\\', $string );
+ $string = str_replace( '$', '\\$', $string );
+ return $string;
+ }
+}
+
+/**
+ * Base class for "replacers", objects used in preg_replace_callback() and
+ * StringUtils::delimiterReplaceCallback()
+ */
+class Replacer {
+ function cb() {
+ return array( &$this, 'replace' );
+ }
+}
+
+/**
+ * Class to replace regex matches with a string similar to that used in preg_replace()
+ */
+class RegexlikeReplacer extends Replacer {
+ var $r;
+ function __construct( $r ) {
+ $this->r = $r;
+ }
+
+ function replace( $matches ) {
+ $pairs = array();
+ foreach ( $matches as $i => $match ) {
+ $pairs["\$$i"] = $match;
+ }
+ return strtr( $this->r, $pairs );
+ }
+
+}
+
+/**
+ * Class to perform secondary replacement within each replacement string
+ */
+class DoubleReplacer extends Replacer {
+ function __construct( $from, $to, $index = 0 ) {
+ $this->from = $from;
+ $this->to = $to;
+ $this->index = $index;
+ }
+
+ function replace( $matches ) {
+ return str_replace( $this->from, $this->to, $matches[$this->index] );
+ }
+}
+
+/**
+ * Class to perform replacement based on a simple hashtable lookup
+ */
+class HashtableReplacer extends Replacer {
+ var $table, $index;
+
+ function __construct( $table, $index = 0 ) {
+ $this->table = $table;
+ $this->index = $index;
+ }
+
+ function replace( $matches ) {
+ return $this->table[$matches[$this->index]];
+ }
+}
+
+/**
+ * Replacement array for FSS with fallback to strtr()
+ * Supports lazy initialisation of FSS resource
+ */
+class ReplacementArray {
+ /*mostly private*/ var $data = false;
+ /*mostly private*/ var $fss = false;
+
+ /**
+ * Create an object with the specified replacement array
+ * The array should have the same form as the replacement array for strtr()
+ */
+ function __construct( $data = array() ) {
+ $this->data = $data;
+ }
+
+ function __sleep() {
+ return array( 'data' );
+ }
+
+ function __wakeup() {
+ $this->fss = false;
+ }
+
+ /**
+ * Set the whole replacement array at once
+ */
+ function setArray( $data ) {
+ $this->data = $data;
+ $this->fss = false;
+ }
+
+ function getArray() {
+ return $this->data;
+ }
+
+ /**
+ * Set an element of the replacement array
+ */
+ function setPair( $from, $to ) {
+ $this->data[$from] = $to;
+ $this->fss = false;
+ }
+
+ function mergeArray( $data ) {
+ $this->data = array_merge( $this->data, $data );
+ $this->fss = false;
+ }
+
+ function merge( $other ) {
+ $this->data = array_merge( $this->data, $other->data );
+ $this->fss = false;
+ }
+
+ function replace( $subject ) {
+ if ( function_exists( 'fss_prep_replace' ) ) {
+ wfProfileIn( __METHOD__.'-fss' );
+ if ( $this->fss === false ) {
+ $this->fss = fss_prep_replace( $this->data );
+ }
+ $result = fss_exec_replace( $this->fss, $subject );
+ wfProfileOut( __METHOD__.'-fss' );
+ } else {
+ wfProfileIn( __METHOD__.'-strtr' );
+ $result = strtr( $subject, $this->data );
+ wfProfileOut( __METHOD__.'-strtr' );
+ }
+ return $result;
+ }
+}
+
+?>