Function xml_xpathobjtoxmlarray

src/backend/utils/adt/xml.c:3911–3975

* Convert an XML XPath object (the result of evaluating an XPath expression) * to an array of xml values, which are appended to astate. The function * result value is the number of elements in the array. * * If "astate" is NULL then we don't generate the array value, but we still * return the number of elements it would have had. * * Nodesets are converted to an array containing the nodes'

 * to a single-element array containing the value's string representation.
 */
static int
xml_xpathobjtoxmlarray(xmlXPathObjectPtr xpathobj,
					   ArrayBuildState *astate,
					   PgXmlErrorContext *xmlerrcxt)
{
	int			result = 0;
	Datum		datum;
	Oid			datumtype;
	char	   *result_str;

	switch (xpathobj->type)
	{
		case XPATH_NODESET:
			if (xpathobj->nodesetval != NULL)
			{
				result = xpathobj->nodesetval->nodeNr;
				if (astate != NULL)
				{
					int			i;

					for (i = 0; i < result; i++)
					{
						datum = PointerGetDatum(xml_xmlnodetoxmltype(xpathobj->nodesetval->nodeTab[i],
																	 xmlerrcxt));
						(void) accumArrayResult(astate, datum, false,
												XMLOID, CurrentMemoryContext);
					}
				}
			}
			return result;

		case XPATH_BOOLEAN:
			if (astate == NULL)
				return 1;
			datum = BoolGetDatum(xpathobj->boolval);
			datumtype = BOOLOID;
			break;

		case XPATH_NUMBER:
			if (astate == NULL)
				return 1;
			datum = Float8GetDatum(xpathobj->floatval);
			datumtype = FLOAT8OID;
			break;

		case XPATH_STRING:
			if (astate == NULL)
				return 1;
			datum = CStringGetDatum((char *) xpathobj->stringval);
			datumtype = CSTRINGOID;
			break;

		default:
			elog(ERROR, "xpath expression result type %d is unsupported",
				 xpathobj->type);
			return 0;			/* keep compiler quiet */
	}