From 65c5864d7fac46516f17ee89085e349a87ee5bd7 Mon Sep 17 00:00:00 2001
From: Michael Paquier <michael@paquier.xyz>
Date: Wed, 17 Jan 2024 08:53:16 +0900
Subject: [PATCH] xml2: Replace deprecated routines with recommended ones

Some functions are used in the tree and are currently marked as
deprecated by upstream.  This commit refreshes the code to use the
recommended functions, leading to the following changes:
- xmlSubstituteEntitiesDefault() is gone, and needs to be replaced with
XML_PARSE_NOENT for the paths doing the parsing.
- xmlParseMemory() -> xmlReadMemory().

These functions, as well as more functions setting global states, have
been officially marked as deprecated by upstream in August 2022.  Their
replacements exist since the 2001-ish area, as far as I have checked,
so that should be safe.

Author: Dmitry Koval
Discussion: https://postgr.es/m/18274-98d16bc03520665f@postgresql.org
---
 contrib/xml2/xpath.c     | 10 ++++++----
 contrib/xml2/xslt_proc.c | 10 ++++++----
 2 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/contrib/xml2/xpath.c b/contrib/xml2/xpath.c
index a692dc6be8..a967257546 100644
--- a/contrib/xml2/xpath.c
+++ b/contrib/xml2/xpath.c
@@ -74,7 +74,6 @@ pgxml_parser_init(PgXmlStrictness strictness)
 	/* Initialize libxml */
 	xmlInitParser();
 
-	xmlSubstituteEntitiesDefault(1);
 	xmlLoadExtDtdDefaultValue = 1;
 
 	return xmlerrcxt;
@@ -380,8 +379,9 @@ pgxml_xpath(text *document, xmlChar *xpath, xpath_workspace *workspace)
 
 	PG_TRY();
 	{
-		workspace->doctree = xmlParseMemory((char *) VARDATA_ANY(document),
-											docsize);
+		workspace->doctree = xmlReadMemory((char *) VARDATA_ANY(document),
+										   docsize, NULL, NULL,
+										   XML_PARSE_NOENT);
 		if (workspace->doctree != NULL)
 		{
 			workspace->ctxt = xmlXPathNewContext(workspace->doctree);
@@ -624,7 +624,9 @@ xpath_table(PG_FUNCTION_ARGS)
 
 			/* Parse the document */
 			if (xmldoc)
-				doctree = xmlParseMemory(xmldoc, strlen(xmldoc));
+				doctree = xmlReadMemory(xmldoc, strlen(xmldoc),
+										NULL, NULL,
+										XML_PARSE_NOENT);
 			else				/* treat NULL as not well-formed */
 				doctree = NULL;
 
diff --git a/contrib/xml2/xslt_proc.c b/contrib/xml2/xslt_proc.c
index 2189bca86f..f30a3a42c0 100644
--- a/contrib/xml2/xslt_proc.c
+++ b/contrib/xml2/xslt_proc.c
@@ -85,16 +85,18 @@ xslt_process(PG_FUNCTION_ARGS)
 		bool		xslt_sec_prefs_error;
 
 		/* Parse document */
-		doctree = xmlParseMemory((char *) VARDATA_ANY(doct),
-								 VARSIZE_ANY_EXHDR(doct));
+		doctree = xmlReadMemory((char *) VARDATA_ANY(doct),
+								VARSIZE_ANY_EXHDR(doct), NULL, NULL,
+								XML_PARSE_NOENT);
 
 		if (doctree == NULL)
 			xml_ereport(xmlerrcxt, ERROR, ERRCODE_EXTERNAL_ROUTINE_EXCEPTION,
 						"error parsing XML document");
 
 		/* Same for stylesheet */
-		ssdoc = xmlParseMemory((char *) VARDATA_ANY(ssheet),
-							   VARSIZE_ANY_EXHDR(ssheet));
+		ssdoc = xmlReadMemory((char *) VARDATA_ANY(ssheet),
+							  VARSIZE_ANY_EXHDR(ssheet), NULL, NULL,
+							  XML_PARSE_NOENT);
 
 		if (ssdoc == NULL)
 			xml_ereport(xmlerrcxt, ERROR, ERRCODE_EXTERNAL_ROUTINE_EXCEPTION,