db/txn/txn_rec.c

/*-
 * See the file LICENSE for redistribution information.
 *
 * Copyright (c) 1996, 1997, 1998
 *  Sleepycat Software.  All rights reserved.
 */
/*
 * Copyright (c) 1996
 *  The President and Fellows of Harvard University.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *  This product includes software developed by the University of
 *  California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include "config.h"

#ifndef lint
static const char sccsid[] = "@(#)txn_rec.c 10.15 (Sleepycat) 1/3/99";
#endif /* not lint */

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

#include <errno.h>
#endif

#include "db_int.h"
#include "db_page.h"
#include "shqueue.h"
#include "txn.h"
#include "db_am.h"
#include "log.h"
#include "common_ext.h"

static int __txn_restore_txn __P((DB_ENV *, DB_LSN *, __txn_xa_regop_args *));

#define IS_XA_TXN(R) (R->xid.size != 0)

/*
 * PUBLIC: int __txn_regop_recover
 * PUBLIC:    __P((DB_LOG *, DBT *, DB_LSN *, int, void *));
 *
 * These records are only ever written for commits.
 */
int
__txn_regop_recover(logp, dbtp, lsnp, redo, info)
    DB_LOG *logp;
    DBT *dbtp;
    DB_LSN *lsnp;
    int redo;
    void *info;
{
    __txn_regop_args *argp;
    int ret;

#ifdef DEBUG_RECOVER
    (void)__txn_regop_print(logp, dbtp, lsnp, redo, info);
#endif
    COMPQUIET(redo, 0);
    COMPQUIET(logp, NULL);

    if ((ret = __txn_regop_read(dbtp->data, &argp)) != 0)
        return (ret);

    if (argp->opcode != TXN_COMMIT)
        ret = EINVAL;
    else
        if (__db_txnlist_find(info, argp->txnid->txnid) == DB_NOTFOUND)
            ret = __db_txnlist_add(info, argp->txnid->txnid);

    if (ret == 0)
        *lsnp = argp->prev_lsn;
    __os_free(argp, 0);

    return (ret);
}

/*
 * PUBLIC: int __txn_xa_regop_recover
 * PUBLIC:    __P((DB_LOG *, DBT *, DB_LSN *, int, void *));
 *
 * These records are only ever written for prepares.
 */
int
__txn_xa_regop_recover(logp, dbtp, lsnp, redo, info)
    DB_LOG *logp;
    DBT *dbtp;
    DB_LSN *lsnp;
    int redo;
    void *info;
{
    __txn_xa_regop_args *argp;
    int ret;

#ifdef DEBUG_RECOVER
    (void)__txn_xa_regop_print(logp, dbtp, lsnp, redo, info);
#endif
    COMPQUIET(redo, 0);
    COMPQUIET(logp, NULL);

    if ((ret = __txn_xa_regop_read(dbtp->data, &argp)) != 0)
        return (ret);

    if (argp->opcode != TXN_PREPARE)
        ret = EINVAL;
    else {
        /*
         * Whether we are in XA or not, we need to call
         * __db_txnlist_find so that we update the maxid.
         * If this is an XA transaction, then we treat
         * prepares like commits so that we roll forward to
         * a point where we can handle commit/abort calls
         * from the TMS.  If this isn't XA, then a prepare
         * is treated like a No-op; we only care about the
         * commit.
         */
        ret = __db_txnlist_find(info, argp->txnid->txnid);
        if (IS_XA_TXN(argp) && ret == DB_NOTFOUND) {
            /*
             * This is an XA prepared, but not yet committed
             * transaction.  We need to add it to the
             * transaction list, so that it gets rolled
             * forward. We also have to add it to the region's
             * internal state so it can be properly aborted
             * or recovered.
             */
            ret = __db_txnlist_add(info, argp->txnid->txnid);
            if (ret == 0)
                ret = __txn_restore_txn(logp->dbenv,
                    lsnp, argp);
        }
    }

    if (ret == 0)
        *lsnp = argp->prev_lsn;
    __os_free(argp, 0);

    return (ret);
}

/*
 * PUBLIC: int __txn_ckp_recover __P((DB_LOG *, DBT *, DB_LSN *, int, void *));
 */
int
__txn_ckp_recover(logp, dbtp, lsnp, redo, info)
    DB_LOG *logp;
    DBT *dbtp;
    DB_LSN *lsnp;
    int redo;
    void *info;
{
    __txn_ckp_args *argp;
    int ret;

#ifdef DEBUG_RECOVER
    __txn_ckp_print(logp, dbtp, lsnp, redo, info);
#endif
    COMPQUIET(logp, NULL);

    if ((ret = __txn_ckp_read(dbtp->data, &argp)) != 0)
        return (ret);

    /*
     * Check for 'restart' checkpoint record.  This occurs when the
     * checkpoint lsn is equal to the lsn of the checkpoint record
     * and means that we could set the transaction ID back to 1, so
     * that we don't exhaust the transaction ID name space.
     */
    if (argp->ckp_lsn.file == lsnp->file &&
        argp->ckp_lsn.offset == lsnp->offset)
        __db_txnlist_gen(info, redo ? -1 : 1);

    *lsnp = argp->last_ckp;
    __os_free(argp, 0);
    return (DB_TXN_CKP);
}

/*
 * __txn_child_recover
 *  Recover a commit record for a child transaction.
 *
 * PUBLIC: int __txn_child_recover
 * PUBLIC:    __P((DB_LOG *, DBT *, DB_LSN *, int, void *));
 */
int
__txn_child_recover(logp, dbtp, lsnp, redo, info)
    DB_LOG *logp;
    DBT *dbtp;
    DB_LSN *lsnp;
    int redo;
    void *info;
{
    __txn_child_args *argp;
    int ret;

#ifdef DEBUG_RECOVER
    (void)__txn_child_print(logp, dbtp, lsnp, redo, info);
#endif
    COMPQUIET(redo, 0);
    COMPQUIET(logp, NULL);

    if ((ret = __txn_child_read(dbtp->data, &argp)) != 0)
        return (ret);

    /*
     * We count the child as committed only if its parent committed.
     * So, if we are not yet in the transaction list, but our parent
     * is, then we should go ahead and commit.
     */
    if (argp->opcode != TXN_COMMIT)
        ret = EINVAL;
    else
        if (__db_txnlist_find(info, argp->parent) == 0 &&
            __db_txnlist_find(info, argp->txnid->txnid) == DB_NOTFOUND)
            ret = __db_txnlist_add(info, argp->txnid->txnid);

    if (ret == 0)
        *lsnp = argp->prev_lsn;
    __os_free(argp, 0);

    return (ret);
}

/*
 * __txn_restore_txn --
 *  Using only during XA recovery.  If we find any transactions that are
 * prepared, but not yet committed, then we need to restore the transaction's
 * state into the shared region, because the TM is going to issue a txn_abort
 * or txn_commit and we need to respond correctly.
 *
 * lsnp is the LSN of the returned LSN
 * argp is the perpare record (in an appropriate structure)
 */
static int
__txn_restore_txn(dbenv, lsnp, argp)
    DB_ENV *dbenv;
    DB_LSN *lsnp;
    __txn_xa_regop_args *argp;
{
    DB_TXNMGR *mgr;
    TXN_DETAIL *td;
    int ret;

    if (argp->xid.size == 0)
        return(0);

    mgr = dbenv->tx_info;
    LOCK_TXNREGION(mgr);

    /* Allocate a new transaction detail structure. */
    if ((ret = __db_shalloc(mgr->mem, sizeof(TXN_DETAIL), 0, &td)) != 0)
        return (ret);

    /* Place transaction on active transaction list. */
    SH_TAILQ_INSERT_HEAD(&mgr->region->active_txn, td, links, __txn_detail);

    td->txnid = argp->txnid->txnid;
    td->begin_lsn = argp->begin_lsn;
    td->last_lsn = *lsnp;
    td->last_lock = 0;
    td->parent = 0;
    td->status = TXN_PREPARED;
    td->xa_status = TXN_XA_PREPARED;
    memcpy(td->xid, argp->xid.data, argp->xid.size);
    td->bqual = argp->bqual;
    td->gtrid = argp->gtrid;
    td->format = argp->formatID;

    UNLOCK_TXNREGION(mgr);
    return (0);
}