Function untransformRelOptions

src/backend/access/common/reloptions.c:1360–1395

* Convert the text-array format of reloptions into a List of DefElem. * This is the inverse of transformRelOptions(). */

 * This is the inverse of transformRelOptions().
 */
List *
untransformRelOptions(Datum options)
{
	List	   *result = NIL;
	ArrayType  *array;
	Datum	   *optiondatums;
	int			noptions;
	int			i;

	/* Nothing to do if no options */
	if (!PointerIsValid(DatumGetPointer(options)))
		return result;

	array = DatumGetArrayTypeP(options);

	deconstruct_array(array, TEXTOID, -1, false, TYPALIGN_INT,
					  &optiondatums, NULL, &noptions);

	for (i = 0; i < noptions; i++)
	{
		char	   *s;
		char	   *p;
		Node	   *val = NULL;

		s = TextDatumGetCString(optiondatums[i]);
		p = strchr(s, '=');
		if (p)
		{
			*p++ = '\0';
			val = (Node *) makeString(pstrdup(p));
		}
		result = lappend(result, makeDefElem(pstrdup(s), val, -1));
	}

	return result;
}

/*
 * Extract and parse reloptions from a pg_class tuple.