rep.h
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上传日期:2022-05-23
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- /*-
- * See the file LICENSE for redistribution information.
- *
- * Copyright (c) 2001-2002
- * Sleepycat Software. All rights reserved.
- */
- #ifndef _REP_H_
- #define _REP_H_
- #define REP_ALIVE 1 /* I am alive message. */
- #define REP_ALIVE_REQ 2 /* Request for alive messages. */
- #define REP_ALL_REQ 3 /* Request all log records greater than LSN. */
- #define REP_ELECT 4 /* Indicates that all listeners should */
- /* begin master election */
- #define REP_FILE 6 /* Page of a database file. */
- #define REP_FILE_REQ 7 /* Request for a database file. */
- #define REP_LOG 8 /* Log record. */
- #define REP_LOG_MORE 9 /* There are more log records to request. */
- #define REP_LOG_REQ 10 /* Request for a log record. */
- #define REP_MASTER_REQ 11 /* Who is the master */
- #define REP_NEWCLIENT 12 /* Announces the presence of a new client. */
- #define REP_NEWFILE 13 /* Announce a log file change. */
- #define REP_NEWMASTER 14 /* Announces who the master is. */
- #define REP_NEWSITE 15 /* Announces that a site has heard from a new
- * site; like NEWCLIENT, but indirect. A
- * NEWCLIENT message comes directly from the new
- * client while a NEWSITE comes indirectly from
- * someone who heard about a NEWSITE.
- */
- #define REP_PAGE 16 /* Database page. */
- #define REP_PAGE_REQ 17 /* Request for a database page. */
- #define REP_PLIST 18 /* Database page list. */
- #define REP_PLIST_REQ 19 /* Request for a page list. */
- #define REP_VERIFY 20 /* A log record for verification. */
- #define REP_VERIFY_FAIL 21 /* The client is outdated. */
- #define REP_VERIFY_REQ 22 /* Request for a log record to verify. */
- #define REP_VOTE1 23 /* Send out your information for an election. */
- #define REP_VOTE2 24 /* Send a "you are master" vote. */
- /* Used to consistently designate which messages ought to be received where. */
- #define MASTER_ONLY(dbenv)
- if (!F_ISSET(dbenv, DB_ENV_REP_MASTER)) return (EINVAL)
- #define CLIENT_ONLY(dbenv)
- if (!F_ISSET(dbenv, DB_ENV_REP_CLIENT)) return (EINVAL)
- #define ANYSITE(dbenv)
- /* Shared replication structure. */
- typedef struct __rep {
- /*
- * Due to alignment constraints on some architectures (e.g. HP-UX),
- * DB_MUTEXes must be the first element of shalloced structures,
- * and as a corollary there can be only one per structure. Thus,
- * db_mutex_off points to a mutex in a separately-allocated chunk.
- */
- DB_MUTEX mutex; /* Region lock. */
- roff_t db_mutex_off; /* Client database mutex. */
- u_int32_t tally_off; /* Offset of the tally region. */
- int eid; /* Environment id. */
- int master_id; /* ID of the master site. */
- u_int32_t gen; /* Replication generation number */
- int asites; /* Space allocated for sites. */
- int nsites; /* Number of sites in group. */
- int priority; /* My priority in an election. */
- u_int32_t gbytes; /* Limit on data sent in single... */
- u_int32_t bytes; /* __rep_process_message call. */
- #define DB_REP_REQUEST_GAP 4
- #define DB_REP_MAX_GAP 128
- u_int32_t request_gap; /* # of records to receive before we
- * request a missing log record. */
- u_int32_t max_gap; /* Maximum number of records before
- * requesting a missing log record. */
- /* Vote tallying information. */
- int sites; /* Sites heard from. */
- int winner; /* Current winner. */
- int w_priority; /* Winner priority. */
- u_int32_t w_gen; /* Winner generation. */
- DB_LSN w_lsn; /* Winner LSN. */
- int w_tiebreaker; /* Winner tiebreaking value. */
- int votes; /* Number of votes for this site. */
- /* Statistics. */
- DB_REP_STAT stat;
- #define REP_F_EPHASE1 0x01 /* In phase 1 of election. */
- #define REP_F_EPHASE2 0x02 /* In phase 2 of election. */
- #define REP_F_LOGSONLY 0x04 /* Log-site only; cannot be upgraded. */
- #define REP_F_MASTER 0x08 /* Master replica. */
- #define REP_F_RECOVER 0x10
- #define REP_F_UPGRADE 0x20 /* Upgradeable replica. */
- #define REP_ISCLIENT (REP_F_UPGRADE | REP_F_LOGSONLY)
- u_int32_t flags;
- } REP;
- #define IN_ELECTION(R) F_ISSET((R), REP_F_EPHASE1 | REP_F_EPHASE2)
- #define ELECTION_DONE(R) F_CLR((R), REP_F_EPHASE1 | REP_F_EPHASE2)
- /*
- * Per-process replication structure.
- */
- struct __db_rep {
- DB_MUTEX *mutexp;
- DB_MUTEX *db_mutexp; /* Mutex for bookkeeping database. */
- DB *rep_db; /* Bookkeeping database. */
- REP *region; /* In memory structure. */
- int (*rep_send) /* Send function. */
- __P((DB_ENV *,
- const DBT *, const DBT *, int, u_int32_t));
- };
- /*
- * Control structure for replication communication infrastructure.
- *
- * Note that the version information should be at the beginning of the
- * structure, so that we can rearrange the rest of it while letting the
- * version checks continue to work. DB_REPVERSION should be revved any time
- * the rest of the structure changes.
- */
- typedef struct __rep_control {
- #define DB_REPVERSION 1
- u_int32_t rep_version; /* Replication version number. */
- u_int32_t log_version; /* Log version number. */
- DB_LSN lsn; /* Log sequence number. */
- u_int32_t rectype; /* Message type. */
- u_int32_t gen; /* Generation number. */
- u_int32_t flags; /* log_put flag value. */
- } REP_CONTROL;
- /* Election vote information. */
- typedef struct __rep_vote {
- int priority; /* My site's priority. */
- int nsites; /* Number of sites I've been in
- * communication with. */
- int tiebreaker; /* Tie-breaking quasi-random int. */
- } REP_VOTE_INFO;
- /*
- * This structure takes care of representing a transaction.
- * It holds all the records, sorted by page number so that
- * we can obtain locks and apply updates in a deadlock free
- * order.
- */
- typedef struct __lsn_page {
- DB_LSN lsn;
- u_int32_t fid;
- DB_LOCK_ILOCK pgdesc;
- #define LSN_PAGE_NOLOCK 0x0001 /* No lock necessary for log rec. */
- u_int32_t flags;
- } LSN_PAGE;
- typedef struct __txn_recs {
- int npages;
- int nalloc;
- LSN_PAGE *array;
- u_int32_t txnid;
- u_int32_t lockid;
- } TXN_RECS;
- typedef struct __lsn_collection {
- int nlsns;
- int nalloc;
- DB_LSN *array;
- } LSN_COLLECTION;
- /*
- * This is used by the page-prep routines to do the lock_vec call to
- * apply the updates for a single transaction or a collection of
- * transactions.
- */
- typedef struct _linfo {
- int n;
- DB_LOCKREQ *reqs;
- DBT *objs;
- } linfo_t;
- #include "dbinc_auto/rep_ext.h"
- #endif /* !_REP_H_ */