/* ------------------------------------------------------------------------
 *
 * pl_hash_funcs.c
 *		Utility C functions for stored HASH procedures
 *
 * Copyright (c) 2016, Postgres Professional
 *
 * ------------------------------------------------------------------------
 */

#include "pathman.h"

#include "utils/typcache.h"


/* Function declarations */

PG_FUNCTION_INFO_V1( get_type_hash_func );
PG_FUNCTION_INFO_V1( get_hash_part_idx );


/*
 * Returns hash function's OID for a specified type.
 */
Datum
get_type_hash_func(PG_FUNCTION_ARGS)
{
	TypeCacheEntry *tce;
	Oid 			type_oid = PG_GETARG_OID(0);

	tce = lookup_type_cache(type_oid, TYPECACHE_HASH_PROC);

	PG_RETURN_OID(tce->hash_proc);
}

/*
 * Wrapper for hash_to_part_index().
 */
Datum
get_hash_part_idx(PG_FUNCTION_ARGS)
{
	uint32	value = PG_GETARG_UINT32(0),
			part_count = PG_GETARG_UINT32(1);

	PG_RETURN_UINT32(hash_to_part_index(value, part_count));
}