From 19c8dc839b64a43958f08108b85ce8ca98d06a8b Mon Sep 17 00:00:00 2001 From: Heikki Linnakangas Date: Fri, 31 Oct 2008 15:05:00 +0000 Subject: Unite ReadBufferWithFork, ReadBufferWithStrategy, and ZeroOrReadBuffer functions into one ReadBufferExtended function, that takes the strategy and mode as argument. There's three modes, RBM_NORMAL which is the default used by plain ReadBuffer(), RBM_ZERO, which replaces ZeroOrReadBuffer, and a new mode RBM_ZERO_ON_ERROR, which allows callers to read corrupt pages without throwing an error. The FSM needs the new mode to recover from corrupt pages, which could happend if we crash after extending an FSM file, and the new page is "torn". Add fork number to some error messages in bufmgr.c, that still lacked it. --- src/include/storage/bufmgr.h | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) (limited to 'src/include/storage/bufmgr.h') diff --git a/src/include/storage/bufmgr.h b/src/include/storage/bufmgr.h index 72d4aec3979..56f584a78ba 100644 --- a/src/include/storage/bufmgr.h +++ b/src/include/storage/bufmgr.h @@ -7,7 +7,7 @@ * Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * - * $PostgreSQL: pgsql/src/include/storage/bufmgr.h,v 1.115 2008/08/11 11:05:11 heikki Exp $ + * $PostgreSQL: pgsql/src/include/storage/bufmgr.h,v 1.116 2008/10/31 15:05:00 heikki Exp $ * *------------------------------------------------------------------------- */ @@ -31,6 +31,14 @@ typedef enum BufferAccessStrategyType BAS_VACUUM /* VACUUM */ } BufferAccessStrategyType; +/* Possible modes for ReadBufferExtended() */ +typedef enum +{ + RBM_NORMAL, /* Normal read */ + RBM_ZERO, /* Don't read from disk, caller will initialize */ + RBM_ZERO_ON_ERROR /* Read, but return an all-zeros page on error */ +} ReadBufferMode; + /* in globals.c ... this duplicates miscadmin.h */ extern PGDLLIMPORT int NBuffers; @@ -144,13 +152,12 @@ extern PGDLLIMPORT int32 *LocalRefCount; * prototypes for functions in bufmgr.c */ extern Buffer ReadBuffer(Relation reln, BlockNumber blockNum); -extern Buffer ReadBufferWithFork(Relation reln, ForkNumber forkNum, BlockNumber blockNum); -extern Buffer ReadBufferWithStrategy(Relation reln, BlockNumber blockNum, - BufferAccessStrategy strategy); -extern Buffer ReadOrZeroBuffer(Relation reln, ForkNumber forkNum, - BlockNumber blockNum); +extern Buffer ReadBufferExtended(Relation reln, ForkNumber forkNum, + BlockNumber blockNum, ReadBufferMode mode, + BufferAccessStrategy strategy); extern Buffer ReadBufferWithoutRelcache(RelFileNode rnode, bool isTemp, - ForkNumber forkNum, BlockNumber blockNum, bool zeroPage); + ForkNumber forkNum, BlockNumber blockNum, + ReadBufferMode mode, BufferAccessStrategy strategy); extern void ReleaseBuffer(Buffer buffer); extern void UnlockReleaseBuffer(Buffer buffer); extern void MarkBufferDirty(Buffer buffer); -- cgit v1.2.3