db_dispatch.h

/*-
 * See the file LICENSE for redistribution information.
 *
 * Copyright (c) 1996-2005
 *      Sleepycat Software.  All rights reserved.
 */
/*
 * Copyright (c) 1995, 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. 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.
 *
 * $Id: db_dispatch.h,v 12.5 2005/10/19 15:10:44 bostic Exp $
 */

#ifndef _DB_DISPATCH_H_
#define _DB_DISPATCH_H_

/*
 * Declarations and typedefs for the list of transaction IDs used during
 * recovery.  This is a generic list used to pass along whatever information
 * we need during recovery.
 */
typedef enum {
        TXNLIST_DELETE,
        TXNLIST_LSN,
        TXNLIST_PGNO,
        TXNLIST_TXNID
} db_txnlist_type;

#define DB_TXNLIST_MASK(hp, n)  (n % hp->nslots)
struct __db_txnhead {
        u_int32_t maxid;        /* Maximum transaction id. */
        DB_LSN maxlsn;          /* Maximum commit lsn. */
        DB_LSN ckplsn;          /* LSN of last retained checkpoint. */
        DB_LSN trunc_lsn;       /* Lsn to which we are going to truncate;
                                 * make sure we abort anyone after this. */
        u_int32_t generation;   /* Current generation number. */
        u_int32_t gen_alloc;    /* Number of generations allocated. */
        struct {
                u_int32_t generation;
                u_int32_t txn_min;
                u_int32_t txn_max;
        } *gen_array;           /* Array of txnids associated with a gen. */
        u_int nslots;
        LIST_HEAD(__db_headlink, __db_txnlist) head[1];
};

#define DB_LSN_STACK_SIZE 4
struct __db_txnlist {
        db_txnlist_type type;
        LIST_ENTRY(__db_txnlist) links;
        union {
                struct {
                        u_int32_t txnid;
                        u_int32_t generation;
                        u_int32_t status;
                } t;
                struct {
                        u_int32_t stack_size;
                        u_int32_t stack_indx;
                        DB_LSN *lsn_stack;
                } l;
                struct {
                        u_int32_t nentries;
                        u_int32_t maxentry;
                        int32_t locked;
                        char *fname;
                        int32_t fileid;
                        db_pgno_t *pgno_array;
                        u_int8_t uid[DB_FILE_ID_LEN];
                } p;
        } u;
};

/*
 * States for limbo list processing.
 */
typedef enum {
        LIMBO_NORMAL,           /* Normal processing. */
        LIMBO_PREPARE,          /* We are preparing a transaction. */
        LIMBO_RECOVER,          /* We are in recovery. */
        LIMBO_TIMESTAMP,        /* We are recovering to a timestamp. */
        LIMBO_COMPENSATE        /* After recover to ts, generate log records. */
} db_limbo_state;

#endif /* !_DB_DISPATCH_H_ */

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