xa_map.c

/*-
 * See the file LICENSE for redistribution information.
 *
 * Copyright (c) 1996-2005
 *      Sleepycat Software.  All rights reserved.
 *
 * $Id: xa_map.c,v 12.4 2005/10/13 20:42:34 bostic Exp $
 */

#include "db_config.h"

#ifndef NO_SYSTEM_INCLUDES
#include <sys/types.h>

#include <string.h>
#endif

#include "db_int.h"
#include "dbinc/txn.h"

/*
 * This file contains all the mapping information that we need to support
 * the DB/XA interface.
 */

/*
 * __db_rmid_to_env
 *      Return the environment associated with a given XA rmid.
 *
 * PUBLIC: int __db_rmid_to_env __P((int rmid, DB_ENV **envp));
 */
int
__db_rmid_to_env(rmid, dbenvp)
        int rmid;
        DB_ENV **dbenvp;
{
        DB_ENV *dbenv;

        dbenv = TAILQ_FIRST(&DB_GLOBAL(db_envq));
        if (dbenv != NULL && dbenv->xa_rmid == rmid) {
                *dbenvp = dbenv;
                return (0);
        }

        /*
         * When we map an rmid, move that environment to be the first one in
         * the list of environments, so we acquire the correct environment
         * in DB->open.
         */
        for (; dbenv != NULL; dbenv = TAILQ_NEXT(dbenv, links))
                if (dbenv->xa_rmid == rmid) {
                        TAILQ_REMOVE(&DB_GLOBAL(db_envq), dbenv, links);
                        TAILQ_INSERT_HEAD(&DB_GLOBAL(db_envq), dbenv, links);
                        *dbenvp = dbenv;
                        return (0);
                }

        return (1);
}

/*
 * __db_xid_to_txn
 *      Return the txn that corresponds to this XID.
 *
 * PUBLIC: int __db_xid_to_txn __P((DB_ENV *, XID *, roff_t *));
 */
int
__db_xid_to_txn(dbenv, xid, offp)
        DB_ENV *dbenv;
        XID *xid;
        roff_t *offp;
{
        struct __txn_detail *td;

        return (__txn_map_gid(dbenv, (u_int8_t *)xid->data, &td, offp));
}

/*
 * __db_map_rmid
 *      Create a mapping between the specified rmid and environment.
 *
 * PUBLIC: int __db_map_rmid __P((int, DB_ENV *));
 */
int
__db_map_rmid(rmid, dbenv)
        int rmid;
        DB_ENV *dbenv;
{
        dbenv->xa_rmid = rmid;
        TAILQ_INSERT_TAIL(&DB_GLOBAL(db_envq), dbenv, links);
        return (0);
}

/*
 * __db_unmap_rmid
 *      Destroy the mapping for the given rmid.
 *
 * PUBLIC: int __db_unmap_rmid __P((int));
 */
int
__db_unmap_rmid(rmid)
        int rmid;
{
        DB_ENV *e;

        for (e = TAILQ_FIRST(&DB_GLOBAL(db_envq));
            e->xa_rmid != rmid;
            e = TAILQ_NEXT(e, links))
            ;

        if (e == NULL)
                return (EINVAL);

        TAILQ_REMOVE(&DB_GLOBAL(db_envq), e, links);
        return (0);
}

/*
 * __db_map_xid
 *      Create a mapping between this XID and the transaction
 *      "td" in the shared region.
 *
 * PUBLIC: int __db_map_xid __P((DB_ENV *, XID *, TXN_DETAIL *));
 */
int
__db_map_xid(dbenv, xid, td)
        DB_ENV *dbenv;
        XID *xid;
        TXN_DETAIL *td;
{
        TXN_SYSTEM_LOCK(dbenv);
        memcpy(td->xid, xid->data, XIDDATASIZE);
        td->bqual = (u_int32_t)xid->bqual_length;
        td->gtrid = (u_int32_t)xid->gtrid_length;
        td->format = (int32_t)xid->formatID;
        TXN_SYSTEM_UNLOCK(dbenv);

        return (0);
}

/*
 * __db_unmap_xid
 *      Destroy the mapping for the specified XID.
 *
 * PUBLIC: void __db_unmap_xid __P((DB_ENV *, XID *, size_t));
 */

void
__db_unmap_xid(dbenv, xid, off)
        DB_ENV *dbenv;
        XID *xid;
        size_t off;
{
        TXN_DETAIL *td;

        COMPQUIET(xid, NULL);

        td = R_ADDR(&((DB_TXNMGR *)dbenv->tx_handle)->reginfo, off);
        memset(td->xid, 0, sizeof(td->xid));
}

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