Improve XML serialization, URI parsing, and XPath node set processing.

third_party/libxml/src/parser.c

 /*
  * parser.c : an XML 1.0 parser, namespaces and validity support are mostly
  *            implemented on top of the SAX interfaces
  *
  * References:
  *   The XML specification:
  *     http://www.w3.org/TR/REC-xml
  *   Original 1.0 version:
  *     http://www.w3.org/TR/1998/REC-xml-19980210
  *   XML second edition working draft
@@ skipping 8129 matching lines @@
         if ((entity->etype != XML_INTERNAL_PARAMETER_ENTITY) &&
             (entity->etype != XML_EXTERNAL_PARAMETER_ENTITY)) {
             xmlWarningMsg(ctxt, XML_WAR_UNDECLARED_ENTITY,
                   "Internal: %%%s; is not a parameter entity\n",
                           name, NULL);
         } else if (ctxt->input->free != deallocblankswrapper) {
             input = xmlNewBlanksWrapperInputStream(ctxt, entity);
             if (xmlPushInput(ctxt, input) < 0)
                 return;
         } else {
+            if ((entity->etype == XML_EXTERNAL_PARAMETER_ENTITY) &&
+                ((ctxt->options & XML_PARSE_NOENT) == 0) &&
+                ((ctxt->options & XML_PARSE_DTDVALID) == 0) &&
+                ((ctxt->options & XML_PARSE_DTDLOAD) == 0) &&
+                ((ctxt->options & XML_PARSE_DTDATTR) == 0) &&
+                (ctxt->replaceEntities == 0) &&
+                (ctxt->validate == 0))
+                return;
             /*
              * TODO !!!
              * handle the extra spaces added before and after
              * c.f. http://www.w3.org/TR/REC-xml#as-PE
              */
             input = xmlNewEntityInputStream(ctxt, entity);
             if (xmlPushInput(ctxt, input) < 0)
                 return;
             if ((entity->etype == XML_EXTERNAL_PARAMETER_ENTITY) &&
                 (CMP5(CUR_PTR, '<', '?', 'x', 'm', 'l')) &&
@@ skipping 7672 matching lines @@
     if (stream == NULL) {
         xmlFreeParserInputBuffer(input);
         return (NULL);
     }
     inputPush(ctxt, stream);
     return (xmlDoRead(ctxt, URL, encoding, options, 1));
 }
 
 #define bottom_parser
 #include "elfgcchack.h"