Comments and PIs are not allowed in XMPP -> throw an exception.

src/XMPPXMLElementBuilder.m

@@ -0,0 +1,43 @@
+/*
+ * Copyright (c) 2012, Jonathan Schleifer <js@webkeks.org>
+ *
+ * https://webkeks.org/hg/objxmpp/
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice is present in all copies.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#import "XMPPXMLElementBuilder.h"
+
+#import <ObjFW/OFMalformedXMLException.h>
+
+@implementation XMPPXMLElementBuilder
+-		 (void)parser: (OFXMLParser*)parser
+  foundProcessingInstructions: (OFString*)pi
+{
+	@throw [OFMalformedXMLException exceptionWithClass: isa];
+}
+
+- (void)parser: (OFXMLParser*)parser
+  foundComment: (OFString*)comment
+{
+	@throw [OFMalformedXMLException exceptionWithClass: isa];
+}
+@end