Quelle  message.h

/*-------------------------------------------------------------------------
 * message.h
 *    Exports from replication/logical/message.c
 *
 * Copyright (c) 2013-2025, PostgreSQL Global Development Group
 *
 * src/include/replication/message.h
 *-------------------------------------------------------------------------
 */
#ifndef PG_LOGICAL_MESSAGE_H
#define PG_LOGICAL_MESSAGE_H

#include "access/xlog.h"
#include "access/xlogdefs.h"
#include "access/xlogreader.h"

/*
 * Generic logical decoding message wal record.
 */
typedef struct xl_logical_message
{
 Oid   dbId;   /* database Oid emitted from */
 bool  transactional; /* is message transactional? */
 Size  prefix_size; /* length of prefix */
 Size  message_size; /* size of the message */
 /* payload, including null-terminated prefix of length prefix_size */
 char  message[FLEXIBLE_ARRAY_MEMBER];
} xl_logical_message;

#define SizeOfLogicalMessage (offsetof(xl_logical_message, message))

extern XLogRecPtr LogLogicalMessage(const char *prefix, const char *message,
         size_t size, bool transactional,
         bool flush);

/* RMGR API */
#define XLOG_LOGICAL_MESSAGE 0x00
extern void logicalmsg_redo(XLogReaderState *record);
extern void logicalmsg_desc(StringInfo buf, XLogReaderState *record);
extern const char *logicalmsg_identify(uint8 info);

#endif       /* PG_LOGICAL_MESSAGE_H */