postgresql/contrib/pg_freespacemap/pg_freespacemap.c
Heikki Linnakangas 6736da5484 Make the blkno arguments bigints instead of int4s. A signed int4 is not
large enough for block numbers higher than 2^31. The old pre-FSM-rewrite
pg_freespacemap implementation got this right. While we're at it, remove
some unnecessary #includes.
2008-10-02 12:20:50 +00:00

48 lines
1.1 KiB
C

/*-------------------------------------------------------------------------
*
* pg_freespacemap.c
* display contents of a free space map
*
* $PostgreSQL: pgsql/contrib/pg_freespacemap/pg_freespacemap.c,v 1.12 2008/10/02 12:20:50 heikki Exp $
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/heapam.h"
#include "funcapi.h"
#include "storage/block.h"
#include "storage/freespace.h"
PG_MODULE_MAGIC;
Datum pg_freespace(PG_FUNCTION_ARGS);
Datum pg_freespacedump(PG_FUNCTION_ARGS);
/*
* Returns the amount of free space on a given page, according to the
* free space map.
*/
PG_FUNCTION_INFO_V1(pg_freespace);
Datum
pg_freespace(PG_FUNCTION_ARGS)
{
Oid relid = PG_GETARG_OID(0);
int64 blkno = PG_GETARG_INT64(1);
int16 freespace;
Relation rel;
rel = relation_open(relid, AccessShareLock);
if (blkno < 0 || blkno > MaxBlockNumber)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("invalid block number")));
freespace = GetRecordedFreeSpace(rel, blkno);
relation_close(rel, AccessShareLock);
PG_RETURN_INT16(freespace);
}