Fixed bug #73629 (SplDoublyLinkedList::setIteratorMode masks intern flags)

We must not overwrite the SPL_DLLIST_IT_FIX flag when changing the
iterator mode.

Author: cmb69

NEWS

@@ -2,7 +2,9 @@ PHP                                                                        NEWS
 |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
 ?? ??? 2017 PHP 7.0.25
 
-
+- SPL:
+  . Fixed bug #73629 (SplDoublyLinkedList::setIteratorMode masks intern flags).
+    (J. Jeising, cmb)
 
 28 Sep 2017 PHP 7.0.24
 

ext/spl/spl_dllist.c

@@ -733,7 +733,7 @@ SPL_METHOD(SplDoublyLinkedList, setIteratorMode)
 		return;
 	}
 
-	intern->flags = value & SPL_DLLIST_IT_MASK;
+	intern->flags = value & SPL_DLLIST_IT_MASK | intern->flags & SPL_DLLIST_IT_FIX;
 
 	RETURN_LONG(intern->flags);
 }

ext/spl/tests/bug73629.phpt

@@ -0,0 +1,20 @@
+--TEST--
+Bug #73629 (SplDoublyLinkedList::setIteratorMode masks intern flags)
+--FILE--
+<?php
+$q = new SplQueue();
+try {
+    $q->setIteratorMode(SplDoublyLinkedList::IT_MODE_FIFO);
+} catch (Exception $e) {
+    echo 'unexpected exception: ' . $e->getMessage() . "\n";
+}
+try {
+    $q->setIteratorMode(SplDoublyLinkedList::IT_MODE_LIFO);
+} catch (Exception $e) {
+    echo 'expected exception: ' . $e->getMessage() . "\n";
+}
+?>
+===DONE===
+--EXPECTF--
+expected exception: Iterators' LIFO/FIFO modes for SplStack/SplQueue objects are frozen
+===DONE===