mirror of
https://git.postgresql.org/git/postgresql.git
synced 2024-09-12 19:17:54 +02:00
40 lines
945 B
C
40 lines
945 B
C
/*-------------------------------------------------------------------------
|
|
*
|
|
* buf.h
|
|
* Basic buffer manager data types.
|
|
*
|
|
*
|
|
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
|
|
* Portions Copyright (c) 1994, Regents of the University of California
|
|
*
|
|
* $Id: buf.h,v 1.14 2002/06/20 20:29:52 momjian Exp $
|
|
*
|
|
*-------------------------------------------------------------------------
|
|
*/
|
|
#ifndef BUF_H
|
|
#define BUF_H
|
|
|
|
/*
|
|
* Buffer identifiers.
|
|
*
|
|
* Zero is invalid, positive is the index of a shared buffer (1..NBuffers),
|
|
* negative is the index of a local buffer (-1 .. -NLocBuffer).
|
|
*/
|
|
typedef int Buffer;
|
|
|
|
#define InvalidBuffer 0
|
|
|
|
/*
|
|
* BufferIsInvalid
|
|
* True iff the buffer is invalid.
|
|
*/
|
|
#define BufferIsInvalid(buffer) ((buffer) == InvalidBuffer)
|
|
|
|
/*
|
|
* BufferIsLocal
|
|
* True iff the buffer is local (not visible to other servers).
|
|
*/
|
|
#define BufferIsLocal(buffer) ((buffer) < 0)
|
|
|
|
#endif /* BUF_H */
|