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Diffstat (limited to '')
-rw-r--r-- | src/include/replication/syncrep.h | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/src/include/replication/syncrep.h b/src/include/replication/syncrep.h new file mode 100644 index 0000000..9d286b6 --- /dev/null +++ b/src/include/replication/syncrep.h @@ -0,0 +1,115 @@ +/*------------------------------------------------------------------------- + * + * syncrep.h + * Exports from replication/syncrep.c. + * + * Portions Copyright (c) 2010-2020, 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 SyncRepConfigData *SyncRepConfig; + +/* communication variables for parsing synchronous_standby_names GUC */ +extern SyncRepConfigData *syncrep_parse_result; +extern char *syncrep_parse_error_msg; + +/* user-settable parameters for synchronous replication */ +extern 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 */ |