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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#define REP_VERIFY_FAIL 21 /* The client is outdated.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_ */
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