MetaDataStorageSource::getEntityIdFromHostPath: Handle missing metadata set.

git-svn-id: https://simplesamlphp.googlecode.com/svn/trunk@1454 44740490-163a-0410-bde0-09ae8108e29a

lib/SimpleSAML/Metadata/MetaDataStorageSource.php

@@ -107,6 +107,10 @@ abstract class SimpleSAML_Metadata_MetaDataStorageSource {
 	public function getEntityIdFromHostPath($hostPath, $set, $type = 'entityid') {
 
 		$metadataSet = $this->getMetadataSet($set);
+		if ($metadataSet === NULL) {
+			/* This metadata source does not have this metadata set. */
+			return NULL;
+		}
 
 		foreach($metadataSet AS $index => $entry) {