| /*------------------------------------------------------------------------- |
| * |
| * pg_control.h |
| * The system control file "pg_control" is not a heap relation. |
| * However, we define it here so that the format is documented. |
| * |
| * |
| * Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group |
| * Portions Copyright (c) 1994, Regents of the University of California |
| * |
| * $PostgreSQL: pgsql/src/include/catalog/pg_control.h,v 1.33 2006/10/04 00:30:07 momjian Exp $ |
| * |
| *------------------------------------------------------------------------- |
| */ |
| #ifndef PG_CONTROL_H |
| #define PG_CONTROL_H |
| |
| #include <time.h> |
| |
| #include "access/xlogdefs.h" |
| #include "utils/pg_crc.h" |
| #include "port/pg_crc32c.h" |
| |
| |
| /* Version identifier for this pg_control format */ |
| #define PG_CONTROL_VERSION 822 |
| |
| /* |
| * Body of CheckPoint XLOG records. This is declared here because we keep |
| * a copy of the latest one in pg_control for possible disaster recovery. |
| */ |
| typedef struct CheckPoint |
| { |
| XLogRecPtr redo; /* next RecPtr available when we began to |
| * create CheckPoint (i.e. REDO start point) */ |
| XLogRecPtr undo; /* first record of oldest in-progress |
| * transaction when we started (i.e. UNDO end |
| * point) */ |
| TimeLineID ThisTimeLineID; /* current TLI */ |
| uint32 nextXidEpoch; /* higher-order bits of nextXid */ |
| TransactionId nextXid; /* next free XID */ |
| Oid nextOid; /* next free OID */ |
| MultiXactId nextMulti; /* next free MultiXactId */ |
| MultiXactOffset nextMultiOffset; /* next free MultiXact offset */ |
| time_t time; /* time stamp of checkpoint */ |
| |
| /* IN XLOG RECORD, MORE DATA FOLLOWS AT END OF STRUCT FOR DTM CHECKPOINT */ |
| |
| } CheckPoint; |
| |
| /* XLOG info values for XLOG rmgr */ |
| #define XLOG_CHECKPOINT_SHUTDOWN 0x00 |
| #define XLOG_CHECKPOINT_ONLINE 0x10 |
| #define XLOG_NEXTOID 0x30 |
| #define XLOG_SWITCH 0x40 |
| |
| |
| /* System status indicator */ |
| typedef enum DBState |
| { |
| DB_STARTUP = 0, |
| DB_SHUTDOWNED, |
| DB_SHUTDOWNING, |
| DB_IN_CRASH_RECOVERY, |
| DB_IN_ARCHIVE_RECOVERY, |
| DB_IN_PRODUCTION |
| } DBState; |
| |
| #define LOCALE_NAME_BUFLEN 128 |
| |
| /* |
| * Contents of pg_control. |
| * |
| * NOTE: try to keep this under 512 bytes so that it will fit on one physical |
| * sector of typical disk drives. This reduces the odds of corruption due to |
| * power failure midway through a write. Currently it fits comfortably, |
| * but we could probably reduce LOCALE_NAME_BUFLEN if things get tight. |
| */ |
| |
| typedef struct ControlFileData |
| { |
| /* |
| * Unique system identifier --- to ensure we match up xlog files with the |
| * installation that produced them. |
| */ |
| uint64 system_identifier; |
| |
| /* |
| * Version identifier information. Keep these fields at the same offset, |
| * especially pg_control_version; they won't be real useful if they move |
| * around. (For historical reasons they must be 8 bytes into the file |
| * rather than immediately at the front.) |
| * |
| * pg_control_version identifies the format of pg_control itself. |
| * catalog_version_no identifies the format of the system catalogs. |
| * |
| * There are additional version identifiers in individual files; for |
| * example, WAL logs contain per-page magic numbers that can serve as |
| * version cues for the WAL log. |
| */ |
| uint32 pg_control_version; /* PG_CONTROL_VERSION */ |
| uint32 catalog_version_no; /* see catversion.h */ |
| |
| /* |
| * System status data |
| */ |
| DBState state; /* see enum above */ |
| time_t time; /* time stamp of last pg_control update */ |
| uint32 logId; /* current log file id */ |
| uint32 logSeg; /* current log file segment, + 1 */ |
| XLogRecPtr checkPoint; /* last check point record ptr */ |
| XLogRecPtr prevCheckPoint; /* previous check point record ptr */ |
| |
| CheckPoint checkPointCopy; /* copy of last check point record */ |
| |
| XLogRecPtr minRecoveryPoint; /* must replay xlog to here */ |
| |
| /* |
| * This data is used to check for hardware-architecture compatibility of |
| * the database and the backend executable. We need not check endianness |
| * explicitly, since the pg_control version will surely look wrong to a |
| * machine of different endianness, but we do need to worry about MAXALIGN |
| * and floating-point format. (Note: storage layout nominally also |
| * depends on SHORTALIGN and INTALIGN, but in practice these are the same |
| * on all architectures of interest.) |
| * |
| * Testing just one double value is not a very bulletproof test for |
| * floating-point compatibility, but it will catch most cases. |
| */ |
| uint32 maxAlign; /* alignment requirement for tuples */ |
| double floatFormat; /* constant 1234567.0 */ |
| #define FLOATFORMAT_VALUE 1234567.0 |
| |
| /* |
| * This data is used to make sure that configuration of this database is |
| * compatible with the backend executable. |
| */ |
| uint32 blcksz; /* data block size for this DB */ |
| uint32 relseg_size; /* blocks per segment of large relation */ |
| |
| uint32 xlog_blcksz; /* block size within WAL files */ |
| uint32 xlog_seg_size; /* size of each WAL segment */ |
| |
| uint32 nameDataLen; /* catalog name field width */ |
| uint32 indexMaxKeys; /* max number of columns in an index */ |
| |
| /* flag indicating internal format of timestamp, interval, time */ |
| uint32 enableIntTimes; /* int64 storage enabled? */ |
| |
| /* active locales */ |
| uint32 localeBuflen; |
| char lc_collate[LOCALE_NAME_BUFLEN]; |
| char lc_ctype[LOCALE_NAME_BUFLEN]; |
| |
| /* CRC of all above ... MUST BE LAST! */ |
| pg_crc32 crc; |
| } ControlFileData; |
| |
| /* |
| * Physical size of the pg_control file. Note that this is considerably |
| * bigger than the actually used size (ie, sizeof(ControlFileData)). |
| * The idea is to keep the physical size constant independent of format |
| * changes, so that ReadControlFile will deliver a suitable wrong-version |
| * message instead of a read error if it's looking at an incompatible file. |
| */ |
| #define PG_CONTROL_SIZE 8192 |
| |
| #endif /* PG_CONTROL_H */ |