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diff --git a/db/db_dispatch.c b/db/db_dispatch.c
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+/*-
+ * See the file LICENSE for redistribution information.
+ *
+ * Copyright (c) 1996-2009 Oracle. 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.
+ *
+ * $Id$
+ */
+
+#include "db_config.h"
+
+#include "db_int.h"
+#include "dbinc/db_page.h"
+#include "dbinc/hash.h"
+#include "dbinc/fop.h"
+#include "dbinc/lock.h"
+#include "dbinc/log.h"
+#include "dbinc/mp.h"
+#include "dbinc/txn.h"
+
+static int __db_txnlist_find_internal __P((ENV *, DB_TXNHEAD *,
+ db_txnlist_type, u_int32_t, DB_TXNLIST **,
+ int, u_int32_t *));
+
+/*
+ * __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 __db_dispatch __P((ENV *,
+ * PUBLIC: DB_DISTAB *, DBT *, DB_LSN *, db_recops, DB_TXNHEAD *));
+ */
+int
+__db_dispatch(env, dtab, db, lsnp, redo, info)
+ ENV *env; /* The environment. */
+ DB_DISTAB *dtab;
+ DBT *db; /* The log record upon which to dispatch. */
+ DB_LSN *lsnp; /* The lsn of the record being dispatched. */
+ db_recops redo; /* Redo this op (or undo it). */
+ DB_TXNHEAD *info; /* Transaction list. */
+{
+ DB_ENV *dbenv;
+ DB_LSN prev_lsn;
+ u_int32_t rectype, status, txnid, urectype;
+ int make_call, ret;
+
+ dbenv = env->dbenv;
+ LOGCOPY_32(env, &rectype, db->data);
+ LOGCOPY_32(env, &txnid, (u_int8_t *)db->data + sizeof(rectype));
+
+ make_call = ret = 0;
+
+ /* If we don't have a dispatch table, it's hard to dispatch. */
+ DB_ASSERT(env, dtab != NULL);
+
+ /*
+ * If we find a record that is in the user's number space and they
+ * have specified a recovery routine, let them handle it. If they
+ * didn't specify a recovery routine, then we expect that they've
+ * followed all our rules and registered new recovery functions.
+ */
+ switch (redo) {
+ case DB_TXN_ABORT:
+ case DB_TXN_APPLY:
+ case DB_TXN_PRINT:
+ make_call = 1;
+ break;
+ case DB_TXN_OPENFILES:
+ /*
+ * We collect all the transactions that have
+ * "begin" records, those with no previous LSN,
+ * so that we do not abort partial transactions.
+ * These are known to be undone, otherwise the
+ * log would not have been freeable.
+ */
+ LOGCOPY_TOLSN(env, &prev_lsn, (u_int8_t *)db->data +
+ sizeof(rectype) + sizeof(txnid));
+ if (txnid != 0 && prev_lsn.file == 0 && (ret =
+ __db_txnlist_add(env, info, txnid, TXN_OK, NULL)) != 0)
+ return (ret);
+
+ /* FALLTHROUGH */
+ case DB_TXN_POPENFILES:
+ if (rectype == DB___dbreg_register ||
+ rectype == DB___txn_child ||
+ rectype == DB___txn_ckp || rectype == DB___txn_recycle)
+ return ((dtab->int_dispatch[rectype])(env,
+ db, lsnp, redo, info));
+ break;
+ case DB_TXN_BACKWARD_ROLL:
+ /*
+ * Running full recovery in the backward pass. In general,
+ * we only process records during this pass that belong
+ * to aborted transactions. Unfortunately, there are several
+ * exceptions:
+ * 1. If this is a meta-record, one not associated with
+ * a transaction, then we must always process it.
+ * 2. If this is a transaction commit/abort, we must
+ * always process it, so that we know the status of
+ * every transaction.
+ * 3. If this is a child commit, we need to process it
+ * because the outcome of the child transaction depends
+ * on the outcome of the parent.
+ * 4. If this is a dbreg_register record, we must always
+ * process is because they contain non-transactional
+ * closes that must be properly handled.
+ * 5. If this is a noop, we must always undo it so that we
+ * properly handle any aborts before a file was closed.
+ * 6. If this a file remove, we need to process it to
+ * determine if the on-disk file is the same as the
+ * one being described.
+ */
+ switch (rectype) {
+ /*
+ * These either do not belong to a transaction or (regop)
+ * must be processed regardless of the status of the
+ * transaction.
+ */
+ case DB___txn_regop:
+ case DB___txn_recycle:
+ case DB___txn_ckp:
+ make_call = 1;
+ break;
+ /*
+ * These belong to a transaction whose status must be
+ * checked.
+ */
+ case DB___txn_child:
+ case DB___db_noop:
+ case DB___fop_file_remove:
+ case DB___dbreg_register:
+ make_call = 1;
+
+ /* FALLTHROUGH */
+ default:
+ if (txnid == 0)
+ break;
+
+ ret = __db_txnlist_find(env, info, txnid, &status);
+
+ /* If not found, this is an incomplete abort. */
+ if (ret == DB_NOTFOUND)
+ return (__db_txnlist_add(env,
+ info, txnid, TXN_IGNORE, lsnp));
+ if (ret != 0)
+ return (ret);
+
+ /*
+ * If we ignore the transaction, ignore the operation
+ * UNLESS this is a child commit in which case we need
+ * to make sure that the child also gets marked as
+ * ignore.
+ */
+ if (status == TXN_IGNORE && rectype != DB___txn_child) {
+ make_call = 0;
+ break;
+ }
+ if (status == TXN_COMMIT)
+ break;
+
+ /* Set make_call in case we came through default */
+ make_call = 1;
+ if (status == TXN_OK &&
+ (ret = __db_txnlist_update(env,
+ info, txnid, rectype == DB___txn_prepare ?
+ TXN_PREPARE : TXN_ABORT, NULL, &status, 0)) != 0)
+ return (ret);
+ }
+ break;
+ case DB_TXN_FORWARD_ROLL:
+ /*
+ * In the forward pass, if we haven't seen the transaction,
+ * do nothing, else recover it.
+ *
+ * We need to always redo DB___db_noop records, so that we
+ * properly handle any commits after the file was closed.
+ */
+ switch (rectype) {
+ case DB___txn_recycle:
+ case DB___txn_ckp:
+ case DB___db_noop:
+ case DB___dbreg_register:
+ make_call = 1;
+ break;
+
+ default:
+ if (txnid == 0)
+ status = 0;
+ else {
+ ret = __db_txnlist_find(env,
+ info, txnid, &status);
+
+ if (ret == DB_NOTFOUND)
+ /* Break out out of if clause. */
+ ;
+ else if (ret != 0)
+ return (ret);
+ else if (status == TXN_COMMIT) {
+ make_call = 1;
+ break;
+ }
+ }
+
+ }
+ break;
+ default:
+ return (__db_unknown_flag(
+ env, "__db_dispatch", (u_int32_t)redo));
+ }
+
+ if (make_call) {
+ /*
+ * If the debug flag is set then we are logging
+ * records for a non-durable update so that they
+ * may be examined for diagnostic purposes.
+ * So only make the call if we are printing,
+ * otherwise we need to extract the previous
+ * lsn so undo will work properly.
+ */
+ if (rectype & DB_debug_FLAG) {
+ if (redo == DB_TXN_PRINT)
+ rectype &= ~DB_debug_FLAG;
+ else {
+ LOGCOPY_TOLSN(env, lsnp,
+ (u_int8_t *)db->data +
+ sizeof(rectype) +
+ sizeof(txnid));
+ return (0);
+ }
+ }
+ if (rectype >= DB_user_BEGIN) {
+ if (dbenv->app_dispatch != NULL)
+ return (dbenv->app_dispatch(dbenv,
+ db, lsnp, redo));
+
+ /* No application-specific dispatch */
+ urectype = rectype - DB_user_BEGIN;
+ if (urectype > dtab->ext_size ||
+ dtab->ext_dispatch[urectype] == NULL) {
+ __db_errx(env,
+ "Illegal application-specific record type %lu in log",
+ (u_long)rectype);
+ return (EINVAL);
+ }
+ return ((dtab->ext_dispatch[urectype])(dbenv,
+ db, lsnp, redo));
+ } else {
+ if (rectype > dtab->int_size ||
+ dtab->int_dispatch[rectype] == NULL) {
+ __db_errx(env,
+ "Illegal record type %lu in log",
+ (u_long)rectype);
+ return (EINVAL);
+ }
+ return ((dtab->int_dispatch[rectype])(env,
+ db, lsnp, redo, info));
+ }
+ }
+
+ return (0);
+}
+
+/*
+ * __db_add_recovery -- Add recovery functions to the dispatch table.
+ *
+ * We have two versions of this, an external one and an internal one,
+ * because application-specific functions take different arguments
+ * for dispatch (ENV versus DB_ENV).
+ *
+ * This is the external version.
+ *
+ * PUBLIC: int __db_add_recovery __P((DB_ENV *, DB_DISTAB *,
+ * PUBLIC: int (*)(DB_ENV *, DBT *, DB_LSN *, db_recops), u_int32_t));
+ */
+int
+__db_add_recovery(dbenv, dtab, func, ndx)
+ DB_ENV *dbenv;
+ DB_DISTAB *dtab;
+ int (*func) __P((DB_ENV *, DBT *, DB_LSN *, db_recops));
+ u_int32_t ndx;
+{
+ size_t i, nsize;
+ int ret;
+
+ /* Make sure this is an application-specific record. */
+ if (ndx < DB_user_BEGIN) {
+ __db_errx(dbenv->env,
+ "Attempting to add application-specific record with invalid type %lu",
+ (u_long)ndx);
+ return (EINVAL);
+ }
+ ndx -= DB_user_BEGIN;
+
+ /* Check if we have to grow the table. */
+ if (ndx >= dtab->ext_size) {
+ nsize = ndx + 40;
+ if ((ret =
+ __os_realloc(dbenv->env, nsize *
+ sizeof((dtab->ext_dispatch)[0]), &dtab->ext_dispatch))
+ != 0)
+ return (ret);
+ for (i = dtab->ext_size; i < nsize; ++i)
+ (dtab->ext_dispatch)[i] = NULL;
+ dtab->ext_size = nsize;
+ }
+
+ (dtab->ext_dispatch)[ndx] = func;
+ return (0);
+}
+
+/*
+ * __db_add_recovery_int --
+ *
+ * Internal version of dispatch addition function.
+ *
+ *
+ * PUBLIC: int __db_add_recovery_int __P((ENV *, DB_DISTAB *,
+ * PUBLIC: int (*)(ENV *, DBT *, DB_LSN *, db_recops, void *), u_int32_t));
+ */
+int
+__db_add_recovery_int(env, dtab, func, ndx)
+ ENV *env;
+ DB_DISTAB *dtab;
+ int (*func) __P((ENV *, DBT *, DB_LSN *, db_recops, void *));
+ u_int32_t ndx;
+{
+ size_t i, nsize;
+ int ret;
+
+ if (ndx >= DB_user_BEGIN) {
+ __db_errx(env,
+ "Attempting to add internal record with invalid type %lu",
+ (u_long)ndx);
+ return (EINVAL);
+ }
+
+ /* Check if we have to grow the table. */
+ if (ndx >= dtab->int_size) {
+ nsize = ndx + 40;
+ if ((ret =
+ __os_realloc(env, nsize * sizeof((dtab->int_dispatch)[0]),
+ &dtab->int_dispatch)) != 0)
+ return (ret);
+ for (i = dtab->int_size; i < nsize; ++i)
+ (dtab->int_dispatch)[i] = NULL;
+ dtab->int_size = nsize;
+ }
+
+ (dtab->int_dispatch)[ndx] = func;
+ return (0);
+}
+
+/*
+ * __db_txnlist_init --
+ * Initialize transaction linked list.
+ *
+ * PUBLIC: int __db_txnlist_init __P((ENV *, DB_THREAD_INFO *,
+ * PUBLIC: u_int32_t, u_int32_t, DB_LSN *, DB_TXNHEAD **));
+ */
+int
+__db_txnlist_init(env, ip, low_txn, hi_txn, trunc_lsn, retp)
+ ENV *env;
+ DB_THREAD_INFO *ip;
+ u_int32_t low_txn, hi_txn;
+ DB_LSN *trunc_lsn;
+ DB_TXNHEAD **retp;
+{
+ DB_TXNHEAD *headp;
+ u_int32_t size, tmp;
+ int ret;
+
+ /*
+ * Size a hash table.
+ * If low is zero then we are being called during rollback
+ * and we need only one slot.
+ * Hi maybe lower than low if we have recycled txnid's.
+ * The numbers here are guesses about txn density, we can afford
+ * to look at a few entries in each slot.
+ */
+ if (low_txn == 0)
+ size = 1;
+ else {
+ if (hi_txn < low_txn) {
+ tmp = hi_txn;
+ hi_txn = low_txn;
+ low_txn = tmp;
+ }
+ tmp = hi_txn - low_txn;
+ /* See if we wrapped around. */
+ if (tmp > (TXN_MAXIMUM - TXN_MINIMUM) / 2)
+ tmp = (low_txn - TXN_MINIMUM) + (TXN_MAXIMUM - hi_txn);
+ size = tmp / 5;
+ if (size < 100)
+ size = 100;
+ }
+ if ((ret = __os_malloc(env,
+ sizeof(DB_TXNHEAD) + size * sizeof(headp->head), &headp)) != 0)
+ return (ret);
+
+ memset(headp, 0, sizeof(DB_TXNHEAD) + size * sizeof(headp->head));
+ headp->maxid = hi_txn;
+ headp->generation = 0;
+ headp->nslots = size;
+ headp->gen_alloc = 8;
+ headp->thread_info = ip;
+ if ((ret = __os_malloc(env, headp->gen_alloc *
+ sizeof(headp->gen_array[0]), &headp->gen_array)) != 0) {
+ __os_free(env, headp);
+ return (ret);
+ }
+ headp->gen_array[0].generation = 0;
+ headp->gen_array[0].txn_min = TXN_MINIMUM;
+ headp->gen_array[0].txn_max = TXN_MAXIMUM;
+ if (trunc_lsn != NULL) {
+ headp->trunc_lsn = *trunc_lsn;
+ headp->maxlsn = *trunc_lsn;
+ } else {
+ ZERO_LSN(headp->trunc_lsn);
+ ZERO_LSN(headp->maxlsn);
+ }
+ ZERO_LSN(headp->ckplsn);
+
+ *retp = headp;
+ return (0);
+}
+
+#define FIND_GENERATION(hp, txnid, gen) do { \
+ u_int32_t __i; \
+ for (__i = 0; __i <= (hp)->generation; __i++) \
+ /* The range may wrap around the end. */ \
+ if ((hp)->gen_array[__i].txn_min < \
+ (hp)->gen_array[__i].txn_max ? \
+ ((txnid) >= (hp)->gen_array[__i].txn_min && \
+ (txnid) <= (hp)->gen_array[__i].txn_max) : \
+ ((txnid) >= (hp)->gen_array[__i].txn_min || \
+ (txnid) <= (hp)->gen_array[__i].txn_max)) \
+ break; \
+ DB_ASSERT(env, __i <= (hp)->generation); \
+ gen = (hp)->gen_array[__i].generation; \
+} while (0)
+
+/*
+ * __db_txnlist_add --
+ * Add an element to our transaction linked list.
+ *
+ * PUBLIC: int __db_txnlist_add __P((ENV *,
+ * PUBLIC: DB_TXNHEAD *, u_int32_t, u_int32_t, DB_LSN *));
+ */
+int
+__db_txnlist_add(env, hp, txnid, status, lsn)
+ ENV *env;
+ DB_TXNHEAD *hp;
+ u_int32_t txnid, status;
+ DB_LSN *lsn;
+{
+ DB_TXNLIST *elp;
+ int ret;
+
+ if ((ret = __os_malloc(env, sizeof(DB_TXNLIST), &elp)) != 0)
+ return (ret);
+
+ LIST_INSERT_HEAD(&hp->head[DB_TXNLIST_MASK(hp, txnid)], elp, links);
+
+ /* Find the most recent generation containing this ID */
+ FIND_GENERATION(hp, txnid, elp->u.t.generation);
+ elp->type = TXNLIST_TXNID;
+ elp->u.t.txnid = txnid;
+ elp->u.t.status = status;
+ if (txnid > hp->maxid)
+ hp->maxid = txnid;
+ if (lsn != NULL && IS_ZERO_LSN(hp->maxlsn) && status == TXN_COMMIT)
+ hp->maxlsn = *lsn;
+
+ DB_ASSERT(env, lsn == NULL ||
+ status != TXN_COMMIT || LOG_COMPARE(&hp->maxlsn, lsn) >= 0);
+
+ return (0);
+}
+
+/*
+ * __db_txnlist_remove --
+ * Remove an element from our transaction linked list.
+ *
+ * PUBLIC: int __db_txnlist_remove __P((ENV *, DB_TXNHEAD *, u_int32_t));
+ */
+int
+__db_txnlist_remove(env, hp, txnid)
+ ENV *env;
+ DB_TXNHEAD *hp;
+ u_int32_t txnid;
+{
+ DB_TXNLIST *entry;
+ u_int32_t status;
+
+ return (__db_txnlist_find_internal(env,
+ hp, TXNLIST_TXNID, txnid, &entry, 1, &status));
+}
+
+/*
+ * __db_txnlist_ckp --
+ * Used to record the maximum checkpoint that will be retained
+ * after recovery. Typically this is simply the max checkpoint, but
+ * if we are doing client replication recovery or timestamp-based
+ * recovery, we are going to virtually truncate the log and we need
+ * to retain the last checkpoint before the truncation point.
+ *
+ * PUBLIC: void __db_txnlist_ckp __P((ENV *, DB_TXNHEAD *, DB_LSN *));
+ */
+void
+__db_txnlist_ckp(env, hp, ckp_lsn)
+ ENV *env;
+ DB_TXNHEAD *hp;
+ DB_LSN *ckp_lsn;
+{
+
+ COMPQUIET(env, NULL);
+
+ if (IS_ZERO_LSN(hp->ckplsn) && !IS_ZERO_LSN(hp->maxlsn) &&
+ LOG_COMPARE(&hp->maxlsn, ckp_lsn) >= 0)
+ hp->ckplsn = *ckp_lsn;
+}
+
+/*
+ * __db_txnlist_end --
+ * Discard transaction linked list.
+ *
+ * PUBLIC: void __db_txnlist_end __P((ENV *, DB_TXNHEAD *));
+ */
+void
+__db_txnlist_end(env, hp)
+ ENV *env;
+ DB_TXNHEAD *hp;
+{
+ u_int32_t i;
+ DB_TXNLIST *p;
+
+ if (hp == NULL)
+ return;
+
+ for (i = 0; i < hp->nslots; i++)
+ while (hp != NULL && (p = LIST_FIRST(&hp->head[i])) != NULL) {
+ switch (p->type) {
+ case TXNLIST_LSN:
+ __os_free(env, p->u.l.lsn_stack);
+ break;
+ case TXNLIST_DELETE:
+ case TXNLIST_TXNID:
+ default:
+ /*
+ * Possibly an incomplete DB_TXNLIST; just
+ * free it.
+ */
+ break;
+ }
+ LIST_REMOVE(p, links);
+ __os_free(env, p);
+ }
+
+ if (hp->gen_array != NULL)
+ __os_free(env, hp->gen_array);
+ __os_free(env, hp);
+}
+
+/*
+ * __db_txnlist_find --
+ * Checks to see if a txnid with the current generation is in the
+ * txnid list. This returns DB_NOTFOUND if the item isn't in the
+ * list otherwise it returns (like __db_txnlist_find_internal)
+ * the status of the transaction. A txnid of 0 means the record
+ * was generated while not in a transaction.
+ *
+ * PUBLIC: int __db_txnlist_find __P((ENV *,
+ * PUBLIC: DB_TXNHEAD *, u_int32_t, u_int32_t *));
+ */
+int
+__db_txnlist_find(env, hp, txnid, statusp)
+ ENV *env;
+ DB_TXNHEAD *hp;
+ u_int32_t txnid, *statusp;
+{
+ DB_TXNLIST *entry;
+
+ if (txnid == 0)
+ return (DB_NOTFOUND);
+
+ return (__db_txnlist_find_internal(env, hp,
+ TXNLIST_TXNID, txnid, &entry, 0, statusp));
+}
+
+/*
+ * __db_txnlist_update --
+ * Change the status of an existing transaction entry.
+ * Returns DB_NOTFOUND if no such entry exists.
+ *
+ * PUBLIC: int __db_txnlist_update __P((ENV *, DB_TXNHEAD *,
+ * PUBLIC: u_int32_t, u_int32_t, DB_LSN *, u_int32_t *, int));
+ */
+int
+__db_txnlist_update(env, hp, txnid, status, lsn, ret_status, add_ok)
+ ENV *env;
+ DB_TXNHEAD *hp;
+ u_int32_t txnid, status;
+ DB_LSN *lsn;
+ u_int32_t *ret_status;
+ int add_ok;
+{
+ DB_TXNLIST *elp;
+ int ret;
+
+ if (txnid == 0)
+ return (DB_NOTFOUND);
+
+ ret = __db_txnlist_find_internal(env,
+ hp, TXNLIST_TXNID, txnid, &elp, 0, ret_status);
+
+ if (ret == DB_NOTFOUND && add_ok) {
+ *ret_status = status;
+ return (__db_txnlist_add(env, hp, txnid, status, lsn));
+ }
+ if (ret != 0)
+ return (ret);
+
+ if (*ret_status == TXN_IGNORE)
+ return (0);
+
+ elp->u.t.status = status;
+
+ if (lsn != NULL && IS_ZERO_LSN(hp->maxlsn) && status == TXN_COMMIT)
+ hp->maxlsn = *lsn;
+
+ return (ret);
+}
+
+/*
+ * __db_txnlist_find_internal --
+ * Find an entry on the transaction list. If the entry is not there or
+ * the list pointer is not initialized we return DB_NOTFOUND. If the
+ * item is found, we return the status. Currently we always call this
+ * with an initialized list pointer but checking for NULL keeps it general.
+ */
+static int
+__db_txnlist_find_internal(env,
+ hp, type, txnid, txnlistp, delete, statusp)
+ ENV *env;
+ DB_TXNHEAD *hp;
+ db_txnlist_type type;
+ u_int32_t txnid;
+ DB_TXNLIST **txnlistp;
+ int delete;
+ u_int32_t *statusp;
+{
+ struct __db_headlink *head;
+ DB_TXNLIST *p;
+ u_int32_t generation, hash;
+ int ret;
+
+ ret = 0;
+
+ if (hp == NULL)
+ return (DB_NOTFOUND);
+
+ switch (type) {
+ case TXNLIST_TXNID:
+ hash = txnid;
+ FIND_GENERATION(hp, txnid, generation);
+ break;
+ case TXNLIST_DELETE:
+ case TXNLIST_LSN:
+ default:
+ return (__env_panic(env, EINVAL));
+ }
+
+ head = &hp->head[DB_TXNLIST_MASK(hp, hash)];
+ LIST_FOREACH(p, head, links) {
+ if (p->type != type)
+ continue;
+ switch (type) {
+ case TXNLIST_TXNID:
+ if (p->u.t.txnid != txnid ||
+ generation != p->u.t.generation)
+ continue;
+ *statusp = p->u.t.status;
+ break;
+
+ case TXNLIST_DELETE:
+ case TXNLIST_LSN:
+ default:
+ return (__env_panic(env, EINVAL));
+ }
+ if (delete == 1) {
+ LIST_REMOVE(p, links);
+ __os_free(env, p);
+ *txnlistp = NULL;
+ } else if (p != LIST_FIRST(head)) {
+ /* Move it to head of list. */
+ LIST_REMOVE(p, links);
+ LIST_INSERT_HEAD(head, p, links);
+ *txnlistp = p;
+ } else
+ *txnlistp = p;
+ return (ret);
+ }
+
+ return (DB_NOTFOUND);
+}
+
+/*
+ * __db_txnlist_gen --
+ * Change the current generation number.
+ *
+ * PUBLIC: int __db_txnlist_gen __P((ENV *,
+ * PUBLIC: DB_TXNHEAD *, int, u_int32_t, u_int32_t));
+ */
+int
+__db_txnlist_gen(env, hp, incr, min, max)
+ ENV *env;
+ DB_TXNHEAD *hp;
+ int incr;
+ u_int32_t min, max;
+{
+ int ret;
+
+ /*
+ * During recovery generation numbers keep track of "restart"
+ * checkpoints and recycle records. Restart checkpoints occur
+ * whenever we take a checkpoint and there are no outstanding
+ * transactions. When that happens, we can reset transaction IDs
+ * back to TXNID_MINIMUM. Currently we only do the reset
+ * at then end of recovery. Recycle records occur when txnids
+ * are exhausted during runtime. A free range of ids is identified
+ * and logged. This code maintains a stack of ranges. A txnid
+ * is given the generation number of the first range it falls into
+ * in the stack.
+ */
+ if (incr < 0) {
+ --hp->generation;
+ memmove(hp->gen_array, &hp->gen_array[1],
+ (hp->generation + 1) * sizeof(hp->gen_array[0]));
+ } else {
+ ++hp->generation;
+ if (hp->generation >= hp->gen_alloc) {
+ hp->gen_alloc *= 2;
+ if ((ret = __os_realloc(env, hp->gen_alloc *
+ sizeof(hp->gen_array[0]), &hp->gen_array)) != 0)
+ return (ret);
+ }
+ memmove(&hp->gen_array[1], &hp->gen_array[0],
+ hp->generation * sizeof(hp->gen_array[0]));
+ hp->gen_array[0].generation = hp->generation;
+ hp->gen_array[0].txn_min = min;
+ hp->gen_array[0].txn_max = max;
+ }
+ return (0);
+}
+
+/*
+ * __db_txnlist_lsnadd --
+ * Save the prev_lsn from a txn_child record.
+ *
+ * PUBLIC: int __db_txnlist_lsnadd __P((ENV *, DB_TXNHEAD *, DB_LSN *));
+ */
+int
+__db_txnlist_lsnadd(env, hp, lsnp)
+ ENV *env;
+ DB_TXNHEAD *hp;
+ DB_LSN *lsnp;
+{
+ DB_TXNLIST *elp;
+ int ret;
+
+ if (IS_ZERO_LSN(*lsnp))
+ return (0);
+
+ LIST_FOREACH(elp, &hp->head[0], links)
+ if (elp->type == TXNLIST_LSN)
+ break;
+
+ if (elp == NULL) {
+ if ((ret = __db_txnlist_lsninit(env, hp, lsnp)) != 0)
+ return (ret);
+ return (DB_SURPRISE_KID);
+ }
+
+ if (elp->u.l.stack_indx == elp->u.l.stack_size) {
+ elp->u.l.stack_size <<= 1;
+ if ((ret = __os_realloc(env, sizeof(DB_LSN) *
+ elp->u.l.stack_size, &elp->u.l.lsn_stack)) != 0) {
+ __db_txnlist_end(env, hp);
+ return (ret);
+ }
+ }
+ elp->u.l.lsn_stack[elp->u.l.stack_indx++] = *lsnp;
+
+ return (0);
+}
+
+/*
+ * __db_txnlist_lsnget --
+ *
+ * PUBLIC: int __db_txnlist_lsnget __P((ENV *,
+ * PUBLIC: DB_TXNHEAD *, DB_LSN *, u_int32_t));
+ * Get the lsn saved from a txn_child record.
+ */
+int
+__db_txnlist_lsnget(env, hp, lsnp, flags)
+ ENV *env;
+ DB_TXNHEAD *hp;
+ DB_LSN *lsnp;
+ u_int32_t flags;
+{
+ DB_TXNLIST *elp;
+
+ COMPQUIET(env, NULL);
+ COMPQUIET(flags, 0);
+
+ LIST_FOREACH(elp, &hp->head[0], links)
+ if (elp->type == TXNLIST_LSN)
+ break;
+
+ if (elp == NULL || elp->u.l.stack_indx == 0) {
+ ZERO_LSN(*lsnp);
+ return (0);
+ }
+
+ *lsnp = elp->u.l.lsn_stack[--elp->u.l.stack_indx];
+
+ return (0);
+}
+
+/*
+ * __db_txnlist_lsninit --
+ * Initialize a transaction list with an lsn array entry.
+ *
+ * PUBLIC: int __db_txnlist_lsninit __P((ENV *, DB_TXNHEAD *, DB_LSN *));
+ */
+int
+__db_txnlist_lsninit(env, hp, lsnp)
+ ENV *env;
+ DB_TXNHEAD *hp;
+ DB_LSN *lsnp;
+{
+ DB_TXNLIST *elp;
+ int ret;
+
+ elp = NULL;
+
+ if ((ret = __os_malloc(env, sizeof(DB_TXNLIST), &elp)) != 0)
+ goto err;
+ LIST_INSERT_HEAD(&hp->head[0], elp, links);
+
+ elp->type = TXNLIST_LSN;
+ if ((ret = __os_malloc(env,
+ sizeof(DB_LSN) * DB_LSN_STACK_SIZE, &elp->u.l.lsn_stack)) != 0)
+ goto err;
+ elp->u.l.stack_indx = 1;
+ elp->u.l.stack_size = DB_LSN_STACK_SIZE;
+ elp->u.l.lsn_stack[0] = *lsnp;
+
+ return (0);
+
+err: __db_txnlist_end(env, hp);
+ return (ret);
+}
+
+#ifdef DEBUG
+/*
+ * __db_txnlist_print --
+ * Print out the transaction list.
+ *
+ * PUBLIC: void __db_txnlist_print __P((DB_TXNHEAD *));
+ */
+void
+__db_txnlist_print(hp)
+ DB_TXNHEAD *hp;
+{
+ DB_TXNLIST *p;
+ u_int32_t i;
+ char *txntype;
+
+ printf("Maxid: %lu Generation: %lu\n",
+ (u_long)hp->maxid, (u_long)hp->generation);
+ for (i = 0; i < hp->nslots; i++)
+ LIST_FOREACH(p, &hp->head[i], links) {
+ if (p->type != TXNLIST_TXNID) {
+ printf("Unrecognized type: %d\n", p->type);
+ continue;
+ }
+ switch (p->u.t.status) {
+ case TXN_OK:
+ txntype = "OK";
+ break;
+ case TXN_COMMIT:
+ txntype = "commit";
+ break;
+ case TXN_PREPARE:
+ txntype = "prepare";
+ break;
+ case TXN_ABORT:
+ txntype = "abort";
+ break;
+ case TXN_IGNORE:
+ txntype = "ignore";
+ break;
+ case TXN_EXPECTED:
+ txntype = "expected";
+ break;
+ case TXN_UNEXPECTED:
+ txntype = "unexpected";
+ break;
+ default:
+ txntype = "UNKNOWN";
+ break;
+ }
+ printf("TXNID: %lx(%lu): %s\n",
+ (u_long)p->u.t.txnid,
+ (u_long)p->u.t.generation, txntype);
+ }
+}
+#endif