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-rw-r--r--src/include/replication/syncrep.h115
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diff --git a/src/include/replication/syncrep.h b/src/include/replication/syncrep.h
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+++ b/src/include/replication/syncrep.h
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+/*-------------------------------------------------------------------------
+ *
+ * syncrep.h
+ * Exports from replication/syncrep.c.
+ *
+ * Portions Copyright (c) 2010-2022, PostgreSQL Global Development Group
+ *
+ * IDENTIFICATION
+ * src/include/replication/syncrep.h
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef _SYNCREP_H
+#define _SYNCREP_H
+
+#include "access/xlogdefs.h"
+#include "utils/guc.h"
+
+#define SyncRepRequested() \
+ (max_wal_senders > 0 && synchronous_commit > SYNCHRONOUS_COMMIT_LOCAL_FLUSH)
+
+/* SyncRepWaitMode */
+#define SYNC_REP_NO_WAIT (-1)
+#define SYNC_REP_WAIT_WRITE 0
+#define SYNC_REP_WAIT_FLUSH 1
+#define SYNC_REP_WAIT_APPLY 2
+
+#define NUM_SYNC_REP_WAIT_MODE 3
+
+/* syncRepState */
+#define SYNC_REP_NOT_WAITING 0
+#define SYNC_REP_WAITING 1
+#define SYNC_REP_WAIT_COMPLETE 2
+
+/* syncrep_method of SyncRepConfigData */
+#define SYNC_REP_PRIORITY 0
+#define SYNC_REP_QUORUM 1
+
+/*
+ * SyncRepGetCandidateStandbys returns an array of these structs,
+ * one per candidate synchronous walsender.
+ */
+typedef struct SyncRepStandbyData
+{
+ /* Copies of relevant fields from WalSnd shared-memory struct */
+ pid_t pid;
+ XLogRecPtr write;
+ XLogRecPtr flush;
+ XLogRecPtr apply;
+ int sync_standby_priority;
+ /* Index of this walsender in the WalSnd shared-memory array */
+ int walsnd_index;
+ /* This flag indicates whether this struct is about our own process */
+ bool is_me;
+} SyncRepStandbyData;
+
+/*
+ * Struct for the configuration of synchronous replication.
+ *
+ * Note: this must be a flat representation that can be held in a single
+ * chunk of malloc'd memory, so that it can be stored as the "extra" data
+ * for the synchronous_standby_names GUC.
+ */
+typedef struct SyncRepConfigData
+{
+ int config_size; /* total size of this struct, in bytes */
+ int num_sync; /* number of sync standbys that we need to
+ * wait for */
+ uint8 syncrep_method; /* method to choose sync standbys */
+ int nmembers; /* number of members in the following list */
+ /* member_names contains nmembers consecutive nul-terminated C strings */
+ char member_names[FLEXIBLE_ARRAY_MEMBER];
+} SyncRepConfigData;
+
+extern PGDLLIMPORT SyncRepConfigData *SyncRepConfig;
+
+/* communication variables for parsing synchronous_standby_names GUC */
+extern PGDLLIMPORT SyncRepConfigData *syncrep_parse_result;
+extern PGDLLIMPORT char *syncrep_parse_error_msg;
+
+/* user-settable parameters for synchronous replication */
+extern PGDLLIMPORT char *SyncRepStandbyNames;
+
+/* called by user backend */
+extern void SyncRepWaitForLSN(XLogRecPtr lsn, bool commit);
+
+/* called at backend exit */
+extern void SyncRepCleanupAtProcExit(void);
+
+/* called by wal sender */
+extern void SyncRepInitConfig(void);
+extern void SyncRepReleaseWaiters(void);
+
+/* called by wal sender and user backend */
+extern int SyncRepGetCandidateStandbys(SyncRepStandbyData **standbys);
+
+/* called by checkpointer */
+extern void SyncRepUpdateSyncStandbysDefined(void);
+
+/* GUC infrastructure */
+extern bool check_synchronous_standby_names(char **newval, void **extra, GucSource source);
+extern void assign_synchronous_standby_names(const char *newval, void *extra);
+extern void assign_synchronous_commit(int newval, void *extra);
+
+/*
+ * Internal functions for parsing synchronous_standby_names grammar,
+ * in syncrep_gram.y and syncrep_scanner.l
+ */
+extern int syncrep_yyparse(void);
+extern int syncrep_yylex(void);
+extern void syncrep_yyerror(const char *str);
+extern void syncrep_scanner_init(const char *query_string);
+extern void syncrep_scanner_finish(void);
+
+#endif /* _SYNCREP_H */