database.mod/postgresql.mod/include/replication/worker_internal.h

/*-------------------------------------------------------------------------
 *
 * worker_internal.h
 *	  Internal headers shared by logical replication workers.
 *
 * Portions Copyright (c) 2016-2022, PostgreSQL Global Development Group
 *
 * src/include/replication/worker_internal.h
 *
 *-------------------------------------------------------------------------
 */
#ifndef WORKER_INTERNAL_H
#define WORKER_INTERNAL_H

#include <signal.h>

#include "access/xlogdefs.h"
#include "catalog/pg_subscription.h"
#include "datatype/timestamp.h"
#include "storage/fileset.h"
#include "storage/lock.h"
#include "storage/spin.h"


typedef struct LogicalRepWorker
{
	/* Time at which this worker was launched. */
	TimestampTz launch_time;

	/* Indicates if this slot is used or free. */
	bool		in_use;

	/* Increased every time the slot is taken by new worker. */
	uint16		generation;

	/* Pointer to proc array. NULL if not running. */
	PGPROC	   *proc;

	/* Database id to connect to. */
	Oid			dbid;

	/* User to use for connection (will be same as owner of subscription). */
	Oid			userid;

	/* Subscription id for the worker. */
	Oid			subid;

	/* Used for initial table synchronization. */
	Oid			relid;
	char		relstate;
	XLogRecPtr	relstate_lsn;
	slock_t		relmutex;

	/*
	 * Used to create the changes and subxact files for the streaming
	 * transactions.  Upon the arrival of the first streaming transaction, the
	 * fileset will be initialized, and it will be deleted when the worker
	 * exits.  Under this, separate buffiles would be created for each
	 * transaction which will be deleted after the transaction is finished.
	 */
	FileSet    *stream_fileset;

	/* Stats. */
	XLogRecPtr	last_lsn;
	TimestampTz last_send_time;
	TimestampTz last_recv_time;
	XLogRecPtr	reply_lsn;
	TimestampTz reply_time;
} LogicalRepWorker;

/* Main memory context for apply worker. Permanent during worker lifetime. */
extern PGDLLIMPORT MemoryContext ApplyContext;

/* libpqreceiver connection */
extern PGDLLIMPORT struct WalReceiverConn *LogRepWorkerWalRcvConn;

/* Worker and subscription objects. */
extern PGDLLIMPORT Subscription *MySubscription;
extern PGDLLIMPORT LogicalRepWorker *MyLogicalRepWorker;

extern PGDLLIMPORT bool in_remote_transaction;

extern void logicalrep_worker_attach(int slot);
extern LogicalRepWorker *logicalrep_worker_find(Oid subid, Oid relid,
												bool only_running);
extern List *logicalrep_workers_find(Oid subid, bool only_running);
extern void logicalrep_worker_launch(Oid dbid, Oid subid, const char *subname,
									 Oid userid, Oid relid);
extern void logicalrep_worker_stop(Oid subid, Oid relid);
extern void logicalrep_worker_wakeup(Oid subid, Oid relid);
extern void logicalrep_worker_wakeup_ptr(LogicalRepWorker *worker);

extern int	logicalrep_sync_worker_count(Oid subid);

extern void ReplicationOriginNameForTablesync(Oid suboid, Oid relid,
											  char *originname, int szorgname);
extern char *LogicalRepSyncTableStart(XLogRecPtr *origin_startpos);

extern bool AllTablesyncsReady(void);
extern void UpdateTwoPhaseState(Oid suboid, char new_state);

extern void process_syncing_tables(XLogRecPtr current_lsn);
extern void invalidate_syncing_table_states(Datum arg, int cacheid,
											uint32 hashvalue);

static inline bool
am_tablesync_worker(void)
{
	return OidIsValid(MyLogicalRepWorker->relid);
}

#endif							/* WORKER_INTERNAL_H */