1 files changed, 64 insertions, 0 deletions
diff --git a/includes/PoolCounter.php b/includes/PoolCounter.php
new file mode 100644
index 00000000..2564fbc6
--- /dev/null
+++ b/includes/PoolCounter.php
@@ -0,0 +1,64 @@
+<?php
+
+abstract class PoolCounter {
+	public static function factory( $type, $key ) {
+		global $wgPoolCounterConf;
+		if ( !isset( $wgPoolCounterConf[$type] ) ) {
+			return new PoolCounter_Stub;
+		}
+		$conf = $wgPoolCounterConf[$type];
+		$class = $conf['class'];
+		return new $class( $conf, $type, $key );
+	}
+
+	abstract public function acquire();
+	abstract public function release();
+	abstract public function wait();
+
+	public function executeProtected( $mainCallback, $dirtyCallback = false ) {
+		$status = $this->acquire();
+		if ( !$status->isOK() ) {
+			return $status;
+		}
+		if ( !empty( $status->value['overload'] ) ) {
+			# Overloaded. Try a dirty cache entry.
+			if ( $dirtyCallback ) {
+				if ( call_user_func( $dirtyCallback ) ) {
+					$this->release();
+					return Status::newGood();
+				}
+			}
+
+			# Wait for a thread
+			$status = $this->wait();
+			if ( !$status->isOK() ) {
+				$this->release();
+				return $status;
+			}
+		}
+		# Call the main callback
+		call_user_func( $mainCallback );
+		return $this->release();
+	}
+}
+
+class PoolCounter_Stub extends PoolCounter {
+	public function acquire() {
+		return Status::newGood();
+	}
+
+	public function release() {
+		return Status::newGood();
+	}
+
+	public function wait() {
+		return Status::newGood();
+	}
+
+	public function executeProtected( $mainCallback, $dirtyCallback = false ) {
+		call_user_func( $mainCallback );
+		return Status::newGood();
+	}
+}
+
+