1 files changed, 86 insertions, 69 deletions

diff --git a/src/backend/utils/adt/xml.c b/src/backend/utils/adt/xml.c
index f36aab899a4..28b3eaaa201 100644
--- a/src/backend/utils/adt/xml.c
+++ b/src/backend/utils/adt/xml.c
@@ -1177,6 +1177,36 @@ pg_xmlCharStrndup(const char *str, size_t len)
 }
 
 /*
+ * Copy xmlChar string to PostgreSQL-owned memory, freeing the input.
+ *
+ * The input xmlChar is freed regardless of success of the copy.
+ */
+static char *
+xml_pstrdup_and_free(xmlChar *str)
+{
+	char	   *result;
+
+	if (str)
+	{
+		PG_TRY();
+		{
+			result = pstrdup((char *) str);
+		}
+		PG_CATCH();
+		{
+			xmlFree(str);
+			PG_RE_THROW();
+		}
+		PG_END_TRY();
+		xmlFree(str);
+	}
+	else
+		result = NULL;
+
+	return result;
+}
+
+/*
  * str is the null-terminated input string.  Remaining arguments are
  * output arguments; each can be NULL if value is not wanted.
  * version and encoding are returned as locally-palloc'd strings.
@@ -3678,15 +3708,17 @@ SPI_sql_row_to_xmlelement(uint64 rownum, StringInfo result, char *tablename,
 #ifdef USE_LIBXML
 
 /*
- * Convert XML node to text (dump subtree in case of element,
- * return value otherwise)
+ * Convert XML node to text.
+ *
+ * For attribute and text nodes, return the escaped text.  For anything else,
+ * dump the whole subtree.
  */
 static text *
 xml_xmlnodetoxmltype(xmlNodePtr cur, PgXmlErrorContext *xmlerrcxt)
 {
 	xmltype    *result;
 
-	if (cur->type == XML_ELEMENT_NODE)
+	if (cur->type != XML_ATTRIBUTE_NODE && cur->type != XML_TEXT_NODE)
 	{
 		xmlBufferPtr buf;
 		xmlNodePtr	cur_copy;
@@ -4479,9 +4511,9 @@ XmlTableGetValue(TableFuncScanState *state, int colnum,
 		/*
 		 * There are four possible cases, depending on the number of nodes
 		 * returned by the XPath expression and the type of the target column:
-		 * a) XPath returns no nodes.  b) One node is returned, and column is
-		 * of type XML.  c) One node, column type other than XML.  d) Multiple
-		 * nodes are returned.
+		 * a) XPath returns no nodes.  b) The target type is XML (return all
+		 * as XML).  For non-XML return types:  c) One node (return content).
+		 * d) Multiple nodes (error).
 		 */
 		if (xpathobj->type == XPATH_NODESET)
 		{
@@ -4494,84 +4526,69 @@ XmlTableGetValue(TableFuncScanState *state, int colnum,
 			{
 				*isnull = true;
 			}
-			else if (count == 1 && typid == XMLOID)
-			{
-				text	   *textstr;
-
-				/* simple case, result is one value */
-				textstr = xml_xmlnodetoxmltype(xpathobj->nodesetval->nodeTab[0],
-											   xtCxt->xmlerrcxt);
-				cstr = text_to_cstring(textstr);
-			}
-			else if (count == 1)
+			else
 			{
-				xmlChar    *str;
-				xmlNodePtr	node;
-
-				/*
-				 * Most nodes (elements and even attributes) store their data
-				 * in children nodes. If they don't have children nodes, it
-				 * means that they are empty (e.g. <element/>). Text nodes and
-				 * CDATA sections are an exception: they don't have children
-				 * but have content in the Text/CDATA node itself.
-				 */
-				node = xpathobj->nodesetval->nodeTab[0];
-				if (node->type != XML_CDATA_SECTION_NODE &&
-					node->type != XML_TEXT_NODE)
-					node = node->xmlChildrenNode;
-
-				str = xmlNodeListGetString(xtCxt->doc, node, 1);
-				if (str != NULL)
+				if (typid == XMLOID)
 				{
-					PG_TRY();
-					{
-						cstr = pstrdup((char *) str);
-					}
-					PG_CATCH();
+					text	   *textstr;
+					StringInfoData str;
+
+					/* Concatenate serialized values */
+					initStringInfo(&str);
+					for (int i = 0; i < count; i++)
 					{
-						xmlFree(str);
-						PG_RE_THROW();
+						textstr =
+							xml_xmlnodetoxmltype(xpathobj->nodesetval->nodeTab[i],
+												 xtCxt->xmlerrcxt);
+
+						appendStringInfoText(&str, textstr);
 					}
-					PG_END_TRY();
-					xmlFree(str);
+					cstr = str.data;
 				}
 				else
 				{
-					/* Ensure mapping of empty tags to PostgreSQL values. */
-					cstr = "";
+					xmlChar    *str;
+
+					if (count > 1)
+						ereport(ERROR,
+								(errcode(ERRCODE_CARDINALITY_VIOLATION),
+								 errmsg("more than one value returned by column XPath expression")));
+
+					str = xmlXPathCastNodeSetToString(xpathobj->nodesetval);
+					cstr = str ? xml_pstrdup_and_free(str) : "";
 				}
 			}
+		}
+		else if (xpathobj->type == XPATH_STRING)
+		{
+			/* Content should be escaped when target will be XML */
+			if (typid == XMLOID)
+				cstr = escape_xml((char *) xpathobj->stringval);
 			else
-			{
-				StringInfoData str;
-				int			i;
+				cstr = (char *) xpathobj->stringval;
+		}
+		else if (xpathobj->type == XPATH_BOOLEAN)
+		{
+			char		typcategory;
+			bool		typispreferred;
+			xmlChar    *str;
 
-				Assert(count > 1);
+			/* Allow implicit casting from boolean to numbers */
+			get_type_category_preferred(typid, &typcategory, &typispreferred);
 
-				/*
-				 * When evaluating the XPath expression returns multiple
-				 * nodes, the result is the concatenation of them all. The
-				 * target type must be XML.
-				 */
-				if (typid != XMLOID)
-					ereport(ERROR,
-							(errcode(ERRCODE_CARDINALITY_VIOLATION),
-							 errmsg("more than one value returned by column XPath expression")));
+			if (typcategory != TYPCATEGORY_NUMERIC)
+				str = xmlXPathCastBooleanToString(xpathobj->boolval);
+			else
+				str = xmlXPathCastNumberToString(xmlXPathCastBooleanToNumber(xpathobj->boolval));
 
-				/* Concatenate serialized values */
-				initStringInfo(&str);
-				for (i = 0; i < count; i++)
-				{
-					appendStringInfoText(&str,
-										 xml_xmlnodetoxmltype(xpathobj->nodesetval->nodeTab[i],
-															  xtCxt->xmlerrcxt));
-				}
-				cstr = str.data;
-			}
+			cstr = xml_pstrdup_and_free(str);
 		}
-		else if (xpathobj->type == XPATH_STRING)
+		else if (xpathobj->type == XPATH_NUMBER)
 		{
-			cstr = (char *) xpathobj->stringval;
+			xmlChar    *str;
+
+			str = xmlXPathCastNumberToString(xpathobj->floatval);
+			cstr = xml_pstrdup_and_free(str);
 		}
 		else
 			elog(ERROR, "unexpected XPath object type %u", xpathobj->type);