Remove unnecessary complication around xmlParseBalancedChunkMemory.

When I prepared 71c0921b6 et al yesterday, I was thinking that the
logic involving explicitly freeing the node_list output was still
needed to dodge leakage bugs in libxml2.  But I was misremembering:
we introduced that only because with early 2.13.x releases we could
not trust xmlParseBalancedChunkMemory's result code, so we had to
look to see if a node list was returned or not.  There's no reason
to believe that xmlParseBalancedChunkMemory will fail to clean up
the node list when required, so simplify.  (This essentially
completes reverting all the non-cosmetic changes in 6082b3d5d.)

Reported-by: Jim Jones <jim.jones@uni-muenster.de>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/997668.1753802857@sss.pgh.pa.us
Backpatch-through: 13

diff --git a/src/backend/utils/adt/xml.c b/src/backend/utils/adt/xml.c
index 6ab773472f71fa01b2b5012327df3d87a78b40e6..d6dbb22d918ddae5ed688a3c44d06c1a338fd147 100644 (file)
--- a/src/backend/utils/adt/xml.c
+++ b/src/backend/utils/adt/xml.c
@@ -1862,24 +1862,16 @@ xml_parse(text *data, XmlOptionType xmloption_arg,
            /* allow empty content */
            if (*(utf8string + count))
            {
-               xmlNodePtr  node_list = NULL;
-
                res_code = xmlParseBalancedChunkMemory(doc, NULL, NULL, 0,
                                                       utf8string + count,
-                                                      &node_list);
+                                                      parsed_nodes);
                if (res_code != 0 || xmlerrcxt->err_occurred)
                {
                    xml_errsave(escontext, xmlerrcxt,
                                ERRCODE_INVALID_XML_CONTENT,
                                "invalid XML content");
-                   xmlFreeNodeList(node_list);
                    goto fail;
                }
-
-               if (parsed_nodes != NULL)
-                   *parsed_nodes = node_list;
-               else
-                   xmlFreeNodeList(node_list);
            }
        }