1 files changed, 270 insertions, 0 deletions
diff --git a/db2/db/db_dispatch.c b/db2/db/db_dispatch.c
new file mode 100644
index 0000000000..3d7b162d75
--- /dev/null
+++ b/db2/db/db_dispatch.c
@@ -0,0 +1,270 @@
+/*-
+ * See the file LICENSE for redistribution information.
+ *
+ * Copyright (c) 1996, 1997
+ *	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. 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[] = "@(#)db_dispatch.c	10.5 (Sleepycat) 7/2/97";
+#endif /* not lint */
+
+#ifndef NO_SYSTEM_INCLUDES
+#include <sys/types.h>
+
+#include <errno.h>
+#include <fcntl.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 "common_ext.h"
+
+/*
+ * Data structures to manage the DB dispatch table.  The dispatch table
+ * is a dynamically allocated array of pointers to dispatch functions.
+ * The dispatch_size is the number of entries possible in the current
+ * dispatch table and the dispatch_valid is the number of valid entries
+ * in the dispatch table.
+ */
+static int (**dispatch_table) __P((DB_LOG *, DBT *, DB_LSN *, int, void *));
+static u_int32_t dispatch_size = 0;
+
+/*
+ * __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((DB_LOG *, DBT *, DB_LSN *, int, void *));
+ */
+int
+__db_dispatch(logp, db, lsnp, redo, info)
+	DB_LOG *logp;		/* The log file. */
+	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 ((dispatch_table[rectype])(logp, db, lsnp, redo, info));
+	case TXN_OPENFILES:
+		if (rectype < DB_txn_BEGIN )
+			return ((dispatch_table[rectype])(logp,
+			    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".
+		 */
+		if (__db_txnlist_find(info, txnid) == DB_NOTFOUND)
+			return ((dispatch_table[rectype])(logp,
+			    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.
+		 */
+		if (__db_txnlist_find(info, txnid) != DB_NOTFOUND)
+			return ((dispatch_table[rectype])(logp,
+			    db, lsnp, TXN_REDO, info));
+		break;
+	default:
+		abort();
+	}
+	return (0);
+}
+
+/*
+ * __db_add_recovery --
+ *
+ * PUBLIC: int __db_add_recovery __P((DB_ENV *,
+ * PUBLIC:    int (*)(DB_LOG *, DBT *, DB_LSN *, int, void *), u_int32_t));
+ */
+int
+__db_add_recovery(dbenv, func, ndx)
+	DB_ENV *dbenv;
+	int (*func) __P((DB_LOG *, DBT *, DB_LSN *, int, void *));
+	u_int32_t ndx;
+{
+	u_int32_t i;
+
+	/* Check if function is already registered. */
+	if (dispatch_table && ndx < dispatch_size &&
+	    dispatch_table[ndx] != 0 && dispatch_table[ndx] != func)
+		return (DB_REGISTERED);
+
+	/* Check if we have to grow the table. */
+	if (ndx >= dispatch_size) {
+		if (dispatch_table == NULL)
+			dispatch_table = (int (**)
+			    __P((DB_LOG *, DBT *, DB_LSN *, int, void *)))
+			    malloc(DB_user_BEGIN * sizeof(dispatch_table[0]));
+		else
+			dispatch_table = (int (**)
+			    __P((DB_LOG *, DBT *, DB_LSN *, int, void *)))
+			    realloc(dispatch_table, (DB_user_BEGIN +
+			    dispatch_size) * sizeof(dispatch_table[0]));
+		if (dispatch_table == NULL) {
+			__db_err(dbenv, "%s", strerror(ENOMEM));
+			return (ENOMEM);
+		}
+		for (i = dispatch_size,
+		    dispatch_size += DB_user_BEGIN; i < dispatch_size; ++i)
+			dispatch_table[i] = NULL;
+	}
+
+	dispatch_table[ndx] = func;
+	return (0);
+}
+
+/*
+ * __db_txnlist_init --
+ *	Initialize transaction linked list.
+ *
+ * PUBLIC: int __db_txnlist_init __P((void *));
+ */
+int
+__db_txnlist_init(retp)
+	void *retp;
+{
+	__db_txnhead *headp;
+
+	if ((headp =
+	    (struct __db_txnhead *)malloc(sizeof(struct __db_txnhead))) == NULL)
+		return (ENOMEM);
+
+	LIST_INIT(&headp->head);
+	headp->maxid = 0;
+
+	*(void **)retp = headp;
+	return (0);
+}
+
+/*
+ * __db_txnlist_add --
+ *	Add an element to our transaction linked list.
+ *
+ * PUBLIC: int __db_txnlist_add __P((void *, u_int32_t));
+ */
+int
+__db_txnlist_add(listp, txnid)
+	void *listp;
+	u_int32_t txnid;
+{
+	__db_txnhead *hp;
+	__db_txnlist *elp;
+
+	if ((elp = (__db_txnlist *)malloc(sizeof(__db_txnlist))) == NULL)
+		return (ENOMEM);
+
+	elp->txnid = txnid;
+	hp = (struct __db_txnhead *)listp;
+	LIST_INSERT_HEAD(&hp->head, elp, links);
+	if (txnid > hp->maxid)
+		hp->maxid = txnid;
+
+	return (0);
+}
+
+/*
+ * __db_txnlist_find --
+ *	Checks to see if txnid is in the txnid list, returns 1 if found,
+ *	0 if not found.
+ *
+ * PUBLIC: int __db_txnlist_find __P((void *, u_int32_t));
+ */
+int
+__db_txnlist_find(listp, txnid)
+	void *listp;
+	u_int32_t txnid;
+{
+	__db_txnlist *p;
+	__db_txnhead *hp;
+
+	if ((hp = (struct __db_txnhead *)listp) == NULL)
+		return (DB_NOTFOUND);
+
+	if (hp->maxid < txnid) {
+		hp->maxid = txnid;
+		return (DB_NOTFOUND);
+	}
+
+	for (p = hp->head.lh_first; p != NULL; p = p->links.le_next)
+		if (p->txnid == txnid)
+			return (0);
+
+	return (DB_NOTFOUND);
+}
+
+#ifdef DEBUG
+void
+__db_txnlist_print(listp)
+	void *listp;
+{
+	__db_txnlist *p;
+	__db_txnhead *hp;
+
+	hp = (struct __db_txnhead *)listp;
+	printf("Maxid: %lu\n", (u_long)hp->maxid);
+	for (p = hp->head.lh_first; p != NULL; p = p->links.le_next)
+		printf("TXNID: %lu\n", (u_long)p->txnid);
+}
+#endif