Desist libxml from continuing the parse after a SAX callback has stopped the

third_party/libxml/src/parser.c

Index: third_party/libxml/src/parser.c
===================================================================
--- third_party/libxml/src/parser.c	(revision 100884)
+++ third_party/libxml/src/parser.c	(working copy)
@@ -4827,7 +4827,8 @@
 		    (ctxt->sax->processingInstruction != NULL))
 		    ctxt->sax->processingInstruction(ctxt->userData,
 		                                     target, NULL);
-		ctxt->instate = state;
+		if (ctxt->instate != XML_PARSER_EOF)
+		    ctxt->instate = state;
 		return;
 	    }
 	    buf = (xmlChar *) xmlMallocAtomic(size * sizeof(xmlChar));
@@ -4907,7 +4908,8 @@
 	} else {
 	    xmlFatalErr(ctxt, XML_ERR_PI_NOT_STARTED, NULL);
 	}
-	ctxt->instate = state;
+	if (ctxt->instate != XML_PARSER_EOF)
+	    ctxt->instate = state;
     }
 }
 
@@ -9466,6 +9468,8 @@
     else
 	name = xmlParseStartTag(ctxt);
 #endif /* LIBXML_SAX1_ENABLED */
+    if (ctxt->instate == XML_PARSER_EOF)
+	return;
     if (name == NULL) {
 	spacePop(ctxt);
         return;
@@ -10845,6 +10849,8 @@
 		else
 		    name = xmlParseStartTag(ctxt);
 #endif /* LIBXML_SAX1_ENABLED */
+		if (ctxt->instate == XML_PARSER_EOF)
+		    goto done;
 		if (name == NULL) {
 		    spacePop(ctxt);
 		    ctxt->instate = XML_PARSER_EOF;
@@ -11031,7 +11037,9 @@
 		  else
 		    xmlParseEndTag1(ctxt, 0);
 #endif /* LIBXML_SAX1_ENABLED */
-		if (ctxt->nameNr == 0) {
+		if (ctxt->instate == XML_PARSER_EOF) {
+		    /* Nothing */
+		} else if (ctxt->nameNr == 0) {
 		    ctxt->instate = XML_PARSER_EPILOG;
 		} else {
 		    ctxt->instate = XML_PARSER_CONTENT;