Fixing a function call.

[lhc/web/wiklou.git] / includes / StringUtils.php

diff --git a/includes/StringUtils.php b/includes/StringUtils.php
index 70d0bff..c437b3c 100644 (file)
--- a/includes/StringUtils.php
+++ b/includes/StringUtils.php
@@ -167,6 +167,18 @@ class StringUtils {
                $string = str_replace( '$', '\\$', $string );
                return $string;
        }
+
+       /**
+        * Workalike for explode() with limited memory usage.
+        * Returns an Iterator
+        */
+       static function explode( $separator, $subject ) {
+               if ( substr_count( $subject, $separator ) > 1000 ) {
+                       return new ExplodeIterator( $separator, $subject );
+               } else {
+                       return new ArrayIterator( explode( $separator, $subject ) );
+               }
+       }
 }
 
 /**
@@ -310,3 +322,90 @@ class ReplacementArray {
                return $result;
        }
 }
+
+/**
+ * An iterator which works exactly like:
+ * 
+ * foreach ( explode( $delim, $s ) as $element ) {
+ *    ...
+ * }
+ *
+ * Except it doesn't use 193 byte per element
+ */
+class ExplodeIterator implements Iterator {
+       // The subject string
+       var $subject, $subjectLength;
+
+       // The delimiter
+       var $delim, $delimLength;
+
+       // The position of the start of the line
+       var $curPos;
+
+       // The position after the end of the next delimiter
+       var $endPos;
+
+       // The current token
+       var $current;
+
+       /** 
+        * Construct a DelimIterator
+        */
+       function __construct( $delim, $s ) {
+               $this->subject = $s;
+               $this->delim = $delim;
+
+               // Micro-optimisation (theoretical)
+               $this->subjectLength = strlen( $s );
+               $this->delimLength = strlen( $delim );
+
+               $this->rewind();
+       }
+
+       function rewind() {
+               $this->curPos = 0;
+               $this->endPos = strpos( $this->subject, $this->delim );
+               $this->refreshCurrent();
+       }
+
+
+       function refreshCurrent() {
+               if ( $this->curPos === false ) {
+                       $this->current = false;
+               } elseif ( $this->curPos >= $this->subjectLength ) {
+                       $this->current = '';
+               } elseif ( $this->endPos === false ) {
+                       $this->current = substr( $this->subject, $this->curPos );
+               } else {
+                       $this->current = substr( $this->subject, $this->curPos, $this->endPos - $this->curPos );
+               }
+       }
+
+       function current() {
+               return $this->current;
+       }
+
+       function key() {
+               return $this->curPos;
+       }
+
+       function next() {
+               if ( $this->endPos === false ) {
+                       $this->curPos = false;
+               } else {
+                       $this->curPos = $this->endPos + $this->delimLength;
+                       if ( $this->curPos >= $this->subjectLength ) {
+                               $this->endPos = false;
+                       } else {
+                               $this->endPos = strpos( $this->subject, $this->delim, $this->curPos );
+                       }
+               }
+               $this->refreshCurrent();
+               return $this->current;
+       }
+
+       function valid() {
+               return $this->curPos !== false;
+       }
+}
+