includes/PoolCounter.php

   1 <?php
   2
   3 abstract class PoolCounter {
   4         public static function factory( $type, $key ) {
   5                 global $wgPoolCounterConf;
   6                 if ( !isset( $wgPoolCounterConf[$type] ) ) {
   7                         return new PoolCounter_Stub;
   8                 }
   9                 $conf = $wgPoolCounterConf[$type];
  10                 $class = $conf['class'];
  11                 return new $class( $conf, $type, $key );
  12         }
  13
  14         abstract public function acquire();
  15         abstract public function release();
  16         abstract public function wait();
  17
  18         public function executeProtected( $mainCallback, $dirtyCallback = false ) {
  19                 $status = $this->acquire();
  20                 if ( !$status->isOK() ) {
  21                         return $status;
  22                 }
  23                 if ( !empty( $status->value['overload'] ) ) {
  24                         # Overloaded. Try a dirty cache entry.
  25                         if ( $dirtyCallback ) {
  26                                 if ( call_user_func( $dirtyCallback ) ) {
  27                                         $this->release();
  28                                         return Status::newGood();
  29                                 }
  30                         }
  31
  32                         # Wait for a thread
  33                         $status = $this->wait();
  34                         if ( !$status->isOK() ) {
  35                                 $this->release();
  36                                 return $status;
  37                         }
  38                 }
  39                 # Call the main callback
  40                 call_user_func( $mainCallback );
  41                 return $this->release();
  42         }
  43 }
  44
  45 class PoolCounter_Stub extends PoolCounter {
  46         public function acquire() {
  47                 return Status::newGood();
  48         }
  49
  50         public function release() {
  51                 return Status::newGood();
  52         }
  53
  54         public function wait() {
  55                 return Status::newGood();
  56         }
  57
  58         public function executeProtected( $mainCallback, $dirtyCallback = false ) {
  59                 call_user_func( $mainCallback );
  60                 return Status::newGood();
  61         }
  62 }
  63
  64