codekingpro/portable-devtools

1/*-------------------------------------------------------------------------2 *3 * sync.h4 *	  File synchronization management code.5 *6 * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group7 * Portions Copyright (c) 1994, Regents of the University of California8 *9 * src/include/storage/sync.h10 *11 *-------------------------------------------------------------------------12 */13#ifndef SYNC_H14#define SYNC_H15 16#include "storage/relfilelocator.h"17 18/*19 * Type of sync request.  These are used to manage the set of pending20 * requests to call a sync handler's sync or unlink functions at the next21 * checkpoint.22 */23typedef enum SyncRequestType24{25	SYNC_REQUEST,				/* schedule a call of sync function */26	SYNC_UNLINK_REQUEST,		/* schedule a call of unlink function */27	SYNC_FORGET_REQUEST,		/* forget all calls for a tag */28	SYNC_FILTER_REQUEST			/* forget all calls satisfying match fn */29} SyncRequestType;30 31/*32 * Which set of functions to use to handle a given request.  The values of33 * the enumerators must match the indexes of the function table in sync.c.34 */35typedef enum SyncRequestHandler36{37	SYNC_HANDLER_MD = 0,38	SYNC_HANDLER_CLOG,39	SYNC_HANDLER_COMMIT_TS,40	SYNC_HANDLER_MULTIXACT_OFFSET,41	SYNC_HANDLER_MULTIXACT_MEMBER,42	SYNC_HANDLER_NONE43} SyncRequestHandler;44 45/*46 * A tag identifying a file.  Currently it has the members required for md.c's47 * usage, but sync.c has no knowledge of the internal structure, and it is48 * liable to change as required by future handlers.49 */50typedef struct FileTag51{52	int16		handler;		/* SyncRequestHandler value, saving space */53	int16		forknum;		/* ForkNumber, saving space */54	RelFileLocator rlocator;55	uint32		segno;56} FileTag;57 58extern void InitSync(void);59extern void SyncPreCheckpoint(void);60extern void SyncPostCheckpoint(void);61extern void ProcessSyncRequests(void);62extern void RememberSyncRequest(const FileTag *ftag, SyncRequestType type);63extern bool RegisterSyncRequest(const FileTag *ftag, SyncRequestType type,64								bool retryOnError);65 66#endif							/* SYNC_H */67