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|
/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 1996, 1997, 1998, 1999
* Sleepycat Software. All rights reserved.
*/
/*
* Copyright (c) 1995, 1996
* The President and Fellows of Harvard University. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Margo Seltzer.
*
* 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.
*/
#include "db_config.h"
#ifndef lint
static const char sccsid[] = "@(#)db_dispatch.c 11.7 (Sleepycat) 9/9/99";
#endif /* not lint */
#ifndef NO_SYSTEM_INCLUDES
#include <sys/types.h>
#include <errno.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#endif
#include "db_int.h"
#include "db_page.h"
#include "db_dispatch.h"
#include "db_am.h"
#include "log_auto.h"
#include "txn.h"
#include "txn_auto.h"
#include "log.h"
/*
* CDB___db_dispatch --
*
* This is the transaction dispatch function used by the db access methods.
* It is designed to handle the record format used by all the access
* methods (the one automatically generated by the db_{h,log,read}.sh
* scripts in the tools directory). An application using a different
* recovery paradigm will supply a different dispatch function to txn_open.
*
* PUBLIC: int CDB___db_dispatch __P((DB_ENV *, DBT *, DB_LSN *, int, void *));
*/
int
CDB___db_dispatch(dbenv, db, lsnp, redo, info)
DB_ENV *dbenv; /* The environment. */
DBT *db; /* The log record upon which to dispatch. */
DB_LSN *lsnp; /* The lsn of the record being dispatched. */
int redo; /* Redo this op (or undo it). */
void *info;
{
u_int32_t rectype, txnid;
memcpy(&rectype, db->data, sizeof(rectype));
memcpy(&txnid, (u_int8_t *)db->data + sizeof(rectype), sizeof(txnid));
switch (redo) {
case TXN_REDO:
case TXN_UNDO:
return ((dbenv->dtab[rectype])(dbenv, db, lsnp, redo, info));
case TXN_OPENFILES:
if (rectype < DB_txn_BEGIN )
return ((dbenv->dtab[rectype])(dbenv,
db, lsnp, redo, info));
break;
case TXN_BACKWARD_ROLL:
/*
* Running full recovery in the backward pass. If we've
* seen this txnid before and added to it our commit list,
* then we do nothing during this pass. If we've never
* seen it, then we call the appropriate recovery routine
* in "abort mode".
*
* We need to always undo DB_db_noop records, so that we
* properly handle any aborts before the file was closed.
*/
if (rectype == DB_log_register || rectype == DB_txn_ckp ||
rectype == DB_db_noop ||
(CDB___db_txnlist_find(info, txnid) == DB_NOTFOUND &&
txnid != 0))
return ((dbenv->dtab[rectype])(dbenv,
db, lsnp, TXN_UNDO, info));
break;
case TXN_FORWARD_ROLL:
/*
* In the forward pass, if we haven't seen the transaction,
* do nothing, else recovery it.
*
* We need to always redo DB_db_noop records, so that we
* properly handle any commits after the file was closed.
*/
if (rectype == DB_log_register || rectype == DB_txn_ckp ||
rectype == DB_db_noop ||
CDB___db_txnlist_find(info, txnid) != DB_NOTFOUND)
return ((dbenv->dtab[rectype])(dbenv,
db, lsnp, TXN_REDO, info));
break;
default:
abort();
}
return (0);
}
/*
* CDB___db_add_recovery --
*
* PUBLIC: int CDB___db_add_recovery __P((DB_ENV *,
* PUBLIC: int (*)(DB_ENV *, DBT *, DB_LSN *, int, void *), u_int32_t));
*/
int
CDB___db_add_recovery(dbenv, func, ndx)
DB_ENV *dbenv;
int (*func) __P((DB_ENV *, DBT *, DB_LSN *, int, void *));
u_int32_t ndx;
{
u_int32_t i;
int ret;
/* Check if we have to grow the table. */
if (ndx >= dbenv->dtab_size) {
if ((ret = CDB___os_realloc(
(DB_user_BEGIN + dbenv->dtab_size) * sizeof(dbenv->dtab[0]),
NULL, &dbenv->dtab)) != 0)
return (ret);
for (i = dbenv->dtab_size,
dbenv->dtab_size += DB_user_BEGIN;
i < dbenv->dtab_size; ++i)
dbenv->dtab[i] = NULL;
}
dbenv->dtab[ndx] = func;
return (0);
}
/*
* CDB___db_txnlist_init --
* Initialize transaction linked list.
*
* PUBLIC: int CDB___db_txnlist_init __P((void *));
*/
int
CDB___db_txnlist_init(retp)
void *retp;
{
DB_TXNHEAD *headp;
int ret;
if ((ret = CDB___os_malloc(sizeof(DB_TXNHEAD), NULL, &headp)) != 0)
return (ret);
LIST_INIT(&headp->head);
headp->maxid = 0;
headp->generation = 1;
*(void **)retp = headp;
return (0);
}
/*
* CDB___db_txnlist_add --
* Add an element to our transaction linked list.
*
* PUBLIC: int CDB___db_txnlist_add __P((void *, u_int32_t));
*/
int
CDB___db_txnlist_add(listp, txnid)
void *listp;
u_int32_t txnid;
{
DB_TXNHEAD *hp;
DB_TXNLIST *elp;
int ret;
if ((ret = CDB___os_malloc(sizeof(DB_TXNLIST), NULL, &elp)) != 0)
return (ret);
hp = (DB_TXNHEAD *)listp;
LIST_INSERT_HEAD(&hp->head, elp, links);
elp->type = TXNLIST_TXNID;
elp->u.t.txnid = txnid;
if (txnid > hp->maxid)
hp->maxid = txnid;
elp->u.t.generation = hp->generation;
return (0);
}
/* CDB___db_txnlist_close --
*
* Call this when we close a file. It allows us to reconcile whether
* we have done any operations on this file with whether the file appears
* to have been deleted. If you never do any operations on a file, then
* we assume it's OK to appear deleted.
*
* PUBLIC: int CDB___db_txnlist_close __P((void *, u_int32_t, u_int32_t));
*/
int
CDB___db_txnlist_close(listp, lid, count)
void *listp;
u_int32_t lid;
u_int32_t count;
{
DB_TXNHEAD *hp;
DB_TXNLIST *p;
hp = (DB_TXNHEAD *)listp;
for (p = hp->head.lh_first; p != NULL; p = p->links.le_next) {
if (p->type == TXNLIST_DELETE)
if (lid == p->u.d.fileid &&
!F_ISSET(&p->u.d, TXNLIST_FLAG_CLOSED)) {
p->u.d.count += count;
return (0);
}
}
return (0);
}
/*
* CDB___db_txnlist_delete --
*
* Record that a file was missing or deleted. If the deleted
* flag is set, then we've encountered a delete of a file, else we've
* just encountered a file that is missing. The lid is the log fileid
* and is only meaningful if deleted is not equal to 0.
*
* PUBLIC: int CDB___db_txnlist_delete __P((void *, char *, u_int32_t, int));
*/
int
CDB___db_txnlist_delete(listp, name, lid, deleted)
void *listp;
char *name;
u_int32_t lid;
int deleted;
{
DB_TXNHEAD *hp;
DB_TXNLIST *p;
int ret;
hp = (DB_TXNHEAD *)listp;
for (p = hp->head.lh_first; p != NULL; p = p->links.le_next) {
if (p->type == TXNLIST_DELETE)
if (strcmp(name, p->u.d.fname) == 0) {
if (deleted)
F_SET(&p->u.d, TXNLIST_FLAG_DELETED);
else
F_CLR(&p->u.d, TXNLIST_FLAG_CLOSED);
return (0);
}
}
/* Need to add it. */
if ((ret = CDB___os_malloc(sizeof(DB_TXNLIST), NULL, &p)) != 0)
return (ret);
LIST_INSERT_HEAD(&hp->head, p, links);
p->type = TXNLIST_DELETE;
p->u.d.flags = 0;
if (deleted)
F_SET(&p->u.d, TXNLIST_FLAG_DELETED);
p->u.d.fileid = lid;
p->u.d.count = 0;
ret = CDB___os_strdup(name, &p->u.d.fname);
return (ret);
}
/*
* CDB___db_txnlist_end --
* Discard transaction linked list. Print out any error messages
* for deleted files.
*
* PUBLIC: void CDB___db_txnlist_end __P((DB_ENV *, void *));
*/
void
CDB___db_txnlist_end(dbenv, listp)
DB_ENV *dbenv;
void *listp;
{
DB_TXNHEAD *hp;
DB_TXNLIST *p;
DB_LOG *lp;
hp = (DB_TXNHEAD *)listp;
lp = (DB_LOG *)dbenv->lg_handle;
while (hp != NULL &&
(p = LIST_FIRST(&hp->head)) != LIST_END(&hp->head)) {
LIST_REMOVE(p, links);
if (p->type == TXNLIST_DELETE) {
/*
* If we have a file that is not deleted and has
* some operations, we flag the warning. Since
* the file could still be open, we need to check
* the actual log table as well.
*/
if ((!F_ISSET(&p->u.d, TXNLIST_FLAG_DELETED) &&
p->u.d.count != 0) ||
(!F_ISSET(&p->u.d, TXNLIST_FLAG_CLOSED) &&
p->u.d.fileid < lp->dbentry_cnt &&
lp->dbentry[p->u.d.fileid].count != 0))
CDB___db_err(dbenv, "warning: %s: %s",
p->u.d.fname, CDB_db_strerror(ENOENT));
CDB___os_freestr(p->u.d.fname);
}
CDB___os_free(p, sizeof(DB_TXNLIST));
}
CDB___os_free(listp, sizeof(DB_TXNHEAD));
}
/*
* CDB___db_txnlist_find --
* Checks to see if a txnid with the current generation is in the
* txnid list.
*
* PUBLIC: int CDB___db_txnlist_find __P((void *, u_int32_t));
*/
int
CDB___db_txnlist_find(listp, txnid)
void *listp;
u_int32_t txnid;
{
DB_TXNHEAD *hp;
DB_TXNLIST *p;
if ((hp = (DB_TXNHEAD *)listp) == NULL)
return (DB_NOTFOUND);
for (p = hp->head.lh_first; p != NULL; p = p->links.le_next) {
if (p->type != TXNLIST_TXNID)
continue;
if (p->u.t.txnid == txnid &&
hp->generation == p->u.t.generation)
return (0);
}
return (DB_NOTFOUND);
}
/*
* CDB___db_txnlist_gen --
* Change the current generation number.
*
* PUBLIC: void CDB___db_txnlist_gen __P((void *, int));
*/
void
CDB___db_txnlist_gen(listp, incr)
void *listp;
int incr;
{
DB_TXNHEAD *hp;
/*
* During recovery generation numbers keep track of how many "restart"
* checkpoints we've seen. Restart checkpoints occur whenever we take
* a checkpoint and there are no outstanding transactions. When that
* happens, we can reset transaction IDs back to 1. It always happens
* at recovery and it prevents us from exhausting the transaction IDs
* name space.
*/
hp = (DB_TXNHEAD *)listp;
hp->generation += incr;
}
#ifdef DEBUG
/*
* CDB___db_txnlist_print --
* Print out the transaction list.
*
* PUBLIC: void CDB___db_txnlist_print __P((void *));
*/
void
CDB___db_txnlist_print(listp)
void *listp;
{
DB_TXNHEAD *hp;
DB_TXNLIST *p;
hp = (DB_TXNHEAD *)listp;
printf("Maxid: %lu Generation: %lu\n",
(u_long)hp->maxid, (u_long)hp->generation);
for (p = hp->head.lh_first; p != NULL; p = p->links.le_next) {
switch (p->type) {
case TXNLIST_TXNID:
printf("TXNID: %lu(%lu)\n",
(u_long)p->u.t.txnid, (u_long)p->u.t.generation);
break;
case TXNLIST_DELETE:
printf("FILE: %s id=%d ops=%d %s %s\n",
p->u.d.fname, p->u.d.fileid, p->u.d.count,
F_ISSET(&p->u.d, TXNLIST_FLAG_DELETED) ?
"(deleted)" : "(missing)",
F_ISSET(&p->u.d, TXNLIST_FLAG_CLOSED) ?
"(closed)" : "(open)");
break;
default:
printf("Unrecognized type: %d\n", p->type);
break;
}
}
}
#endif
|