Fix incompatibility with libxml2 >= 2.14

michaelpq · michaelpq · commit 8d1071e7da30 · 2025-07-07T08:54:30.000+09:00
libxml2 has deprecated the members of xmlBuffer, and it is recommended to access them with dedicated routines. We have only one case in the tree where this shows an impact: xml2/xpath.c where "content" was getting directly accessed. The rest of the code looked fine, checking the PostgreSQL code with libxml2 close to the top of its "2.14" branch. xmlBufferContent() exists since year 2000 based on a check of the upstream libxml2 tree, so let's switch to it. Like 400928b, backpatch all the way down as this can have an impact on all the branches already released once newer versions of libxml2 get more popular. Reported-by: Walid Ibrahim <walidib@amazon.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/aGdSdcR4QTjEHX6s@paquier.xyz Backpatch-through: 13
diff --git a/contrib/xml2/xpath.c b/contrib/xml2/xpath.c
@@ -176,7 +176,7 @@ pgxmlNodeSetToText(xmlNodeSetPtr nodeset,
 		xmlBufferWriteCHAR(buf, toptagname);
 		xmlBufferWriteChar(buf, ">");
 	}
-	result = xmlStrdup(buf->content);
+	result = xmlStrdup(xmlBufferContent(buf));
 	xmlBufferFree(buf);
 	return result;
 }

Original file line number	Diff line number	Diff line change
`@@ -176,7 +176,7 @@ pgxmlNodeSetToText(xmlNodeSetPtr nodeset,`
`176`	`176`	`xmlBufferWriteCHAR(buf, toptagname);`
`177`	`177`	`xmlBufferWriteChar(buf, ">");`
`178`	`178`	`}`
`179`		`- result = xmlStrdup(buf->content);`
	`179`	`+ result = xmlStrdup(xmlBufferContent(buf));`
`180`	`180`	`xmlBufferFree(buf);`
`181`	`181`	`return result;`
`182`	`182`	`}`