Merge "Making sister search sidebar links blue"

[lhc/web/wiklou.git] / includes / libs / objectcache / HashBagOStuff.php

diff --git a/includes/libs/objectcache/HashBagOStuff.php b/includes/libs/objectcache/HashBagOStuff.php
index 94bc95f..6d583da 100644 (file)
--- a/includes/libs/objectcache/HashBagOStuff.php
+++ b/includes/libs/objectcache/HashBagOStuff.php
@@ -1,6 +1,6 @@
 <?php
 /**
- * Object caching using PHP arrays.
+ * Per-process memory cache for storing items.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -22,24 +22,37 @@
  */
 
 /**
- * This is a test of the interface, mainly. It stores things in an associative
- * array, which is not going to persist between program runs.
+ * Simple store for keeping values in an associative array for the current process.
+ *
+ * Data will not persist and is not shared with other processes.
  *
  * @ingroup Cache
  */
 class HashBagOStuff extends BagOStuff {
-       /** @var array */
-       protected $bag;
+       /** @var mixed[] */
+       protected $bag = [];
+       /** @var int Max entries allowed */
+       protected $maxCacheKeys;
+
+       const KEY_VAL = 0;
+       const KEY_EXP = 1;
 
-       function __construct( $params = array() ) {
+       /**
+        * @param array $params Additional parameters include:
+        *   - maxKeys : only allow this many keys (using oldest-first eviction)
+        */
+       function __construct( $params = [] ) {
                parent::__construct( $params );
-               $this->bag = array();
+
+               $this->maxCacheKeys = isset( $params['maxKeys'] ) ? $params['maxKeys'] : INF;
+               if ( $this->maxCacheKeys <= 0 ) {
+                       throw new InvalidArgumentException( '$maxKeys parameter must be above zero' );
+               }
        }
 
        protected function expire( $key ) {
-               $et = $this->bag[$key][1];
-
-               if ( ( $et == 0 ) || ( $et > time() ) ) {
+               $et = $this->bag[$key][self::KEY_EXP];
+               if ( $et == self::TTL_INDEFINITE || $et > time() ) {
                        return false;
                }
 
@@ -48,8 +61,19 @@ class HashBagOStuff extends BagOStuff {
                return true;
        }
 
+       /**
+        * Does this bag have a non-null value for the given key?
+        *
+        * @param string $key
+        * @return bool
+        * @since 1.27
+        */
+       protected function hasKey( $key ) {
+               return isset( $this->bag[$key] );
+       }
+
        protected function doGet( $key, $flags = 0 ) {
-               if ( !isset( $this->bag[$key] ) ) {
+               if ( !$this->hasKey( $key ) ) {
                        return false;
                }
 
@@ -57,17 +81,38 @@ class HashBagOStuff extends BagOStuff {
                        return false;
                }
 
-               return $this->bag[$key][0];
+               // Refresh key position for maxCacheKeys eviction
+               $temp = $this->bag[$key];
+               unset( $this->bag[$key] );
+               $this->bag[$key] = $temp;
+
+               return $this->bag[$key][self::KEY_VAL];
        }
 
        public function set( $key, $value, $exptime = 0, $flags = 0 ) {
-               $this->bag[$key] = array( $value, $this->convertExpiry( $exptime ) );
+               // Refresh key position for maxCacheKeys eviction
+               unset( $this->bag[$key] );
+               $this->bag[$key] = [
+                       self::KEY_VAL => $value,
+                       self::KEY_EXP => $this->convertExpiry( $exptime )
+               ];
+
+               if ( count( $this->bag ) > $this->maxCacheKeys ) {
+                       reset( $this->bag );
+                       $evictKey = key( $this->bag );
+                       unset( $this->bag[$evictKey] );
+               }
+
                return true;
        }
 
-       function delete( $key ) {
+       public function delete( $key ) {
                unset( $this->bag[$key] );
 
                return true;
        }
+
+       public function clear() {
+               $this->bag = [];
+       }
 }