hash_rec.c

这是国外的resip协议栈

/*-
 * See the file LICENSE for redistribution information.
 *
 * Copyright (c) 1996-2004
 *	Sleepycat Software.  All rights reserved.
 */
/*
 * Copyright (c) 1995, 1996
 *	Margo Seltzer.  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: hash_rec.c,v 11.83 2004/10/25 16:52:13 ubell Exp $
 */

#include "db_config.h"

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

#include <string.h>
#endif

#include "db_int.h"
#include "dbinc/db_page.h"
#include "dbinc/db_shash.h"
#include "dbinc/btree.h"
#include "dbinc/hash.h"
#include "dbinc/log.h"
#include "dbinc/mp.h"

static int __ham_alloc_pages __P((DB *, __ham_groupalloc_args *, DB_LSN *));

/*
 * __ham_insdel_recover --
 *
 * PUBLIC: int __ham_insdel_recover
 * PUBLIC:     __P((DB_ENV *, DBT *, DB_LSN *, db_recops, void *));
 */
int
__ham_insdel_recover(dbenv, dbtp, lsnp, op, info)
	DB_ENV *dbenv;
	DBT *dbtp;
	DB_LSN *lsnp;
	db_recops op;
	void *info;
{
	__ham_insdel_args *argp;
	DB *file_dbp;
	DBC *dbc;
	DB_MPOOLFILE *mpf;
	PAGE *pagep;
	u_int32_t flags, opcode;
	int cmp_n, cmp_p, ret, type;

	pagep = NULL;
	COMPQUIET(info, NULL);

	REC_PRINT(__ham_insdel_print);
	REC_INTRO(__ham_insdel_read, 1);

	if ((ret = __memp_fget(mpf, &argp->pgno, 0, &pagep)) != 0) {
		if (DB_UNDO(op)) {
			if (ret == DB_PAGE_NOTFOUND)
				goto done;
			else {
				ret = __db_pgerr(file_dbp, argp->pgno, ret);
				goto out;
			}
		}
#ifdef HAVE_FTRUNCATE
		/* If the page is not here then it was later truncated. */
		if (!IS_ZERO_LSN(argp->pagelsn))
			goto done;
#endif
		/*
		 * This page was created by a group allocation and
		 * the file may not have been extend yet.
		 * Create the page if necessary.
		 */
		if ((ret = __memp_fget(mpf,
		     &argp->pgno, DB_MPOOL_CREATE, &pagep)) != 0) {
			ret = __db_pgerr(file_dbp, argp->pgno, ret);
			goto out;
		}
	}

	cmp_n = log_compare(lsnp, &LSN(pagep));
	cmp_p = log_compare(&LSN(pagep), &argp->pagelsn);
	CHECK_LSN(op, cmp_p, &LSN(pagep), &argp->pagelsn);
	/*
	 * Two possible things going on:
	 * redo a delete/undo a put: delete the item from the page.
	 * redo a put/undo a delete: add the item to the page.
	 * If we are undoing a delete, then the information logged is the
	 * entire entry off the page, not just the data of a dbt.  In
	 * this case, we want to copy it back onto the page verbatim.
	 * We do this by calling __putitem with the type H_OFFPAGE instead
	 * of H_KEYDATA.
	 */

	opcode = OPCODE_OF(argp->opcode);
	flags = 0;
	if ((opcode == DELPAIR && cmp_n == 0 && DB_UNDO(op)) ||
	    (opcode == PUTPAIR && cmp_p == 0 && DB_REDO(op))) {
		/*
		 * Need to redo a PUT or undo a delete.  If we are undoing a
		 * delete, we've got to restore the item back to its original
		 * position.  That's a royal pain in the butt (because we do
		 * not store item lengths on the page), but there's no choice.
		 */
		if (opcode != DELPAIR ||
		    argp->ndx == (u_int32_t)NUM_ENT(pagep)) {
			__ham_putitem(file_dbp, pagep, &argp->key,
			    DB_UNDO(op) || PAIR_ISKEYBIG(argp->opcode) ?
			    H_OFFPAGE : H_KEYDATA);

			if (PAIR_ISDATADUP(argp->opcode))
				type = H_DUPLICATE;
			else if (DB_UNDO(op) || PAIR_ISDATABIG(argp->opcode))
				type = H_OFFPAGE;
			else
				type = H_KEYDATA;
			__ham_putitem(file_dbp, pagep, &argp->data, type);
		} else
			__ham_reputpair(file_dbp, pagep,
			    argp->ndx, &argp->key, &argp->data);

		LSN(pagep) = DB_REDO(op) ? *lsnp : argp->pagelsn;
		flags = DB_MPOOL_DIRTY;

	} else if ((opcode == DELPAIR && cmp_p == 0 && DB_REDO(op)) ||
	    (opcode == PUTPAIR && cmp_n == 0 && DB_UNDO(op))) {
		/* Need to undo a put or redo a delete. */
		__ham_dpair(file_dbp, pagep, argp->ndx);
		LSN(pagep) = DB_REDO(op) ? *lsnp : argp->pagelsn;
		flags = DB_MPOOL_DIRTY;
	}

	if ((ret = __memp_fput(mpf, pagep, flags)) != 0)
		goto out;
	pagep = NULL;

	/* Return the previous LSN. */
done:	*lsnp = argp->prev_lsn;
	ret = 0;

out:	if (pagep != NULL)
		(void)__memp_fput(mpf, pagep, 0);
	REC_CLOSE;
}

/*
 * __ham_newpage_recover --
 *	This log message is used when we add/remove overflow pages.  This
 *	message takes care of the pointer chains, not the data on the pages.
 *
 * PUBLIC: int __ham_newpage_recover
 * PUBLIC:     __P((DB_ENV *, DBT *, DB_LSN *, db_recops, void *));
 */
int
__ham_newpage_recover(dbenv, dbtp, lsnp, op, info)
	DB_ENV *dbenv;
	DBT *dbtp;
	DB_LSN *lsnp;
	db_recops op;
	void *info;
{
	__ham_newpage_args *argp;
	DB *file_dbp;
	DBC *dbc;
	DB_MPOOLFILE *mpf;
	PAGE *pagep;
	u_int32_t flags;
	int cmp_n, cmp_p, ret;

	pagep = NULL;
	COMPQUIET(info, NULL);

	REC_PRINT(__ham_newpage_print);
	REC_INTRO(__ham_newpage_read, 1);

	REC_FGET(mpf, argp->new_pgno, &pagep, ppage);

	/*
	 * There are potentially three pages we need to check: the one
	 * that we created/deleted, the one before it and the one after
	 * it.
	 */

	cmp_n = log_compare(lsnp, &LSN(pagep));
	cmp_p = log_compare(&LSN(pagep), &argp->pagelsn);
	CHECK_LSN(op, cmp_p, &LSN(pagep), &argp->pagelsn);

	flags = 0;
	if ((cmp_p == 0 && DB_REDO(op) && argp->opcode == PUTOVFL) ||
	    (cmp_n == 0 && DB_UNDO(op) && argp->opcode == DELOVFL)) {
		/* Redo a create new page or undo a delete new page. */
		P_INIT(pagep, file_dbp->pgsize, argp->new_pgno,
		    argp->prev_pgno, argp->next_pgno, 0, P_HASH);
		flags = DB_MPOOL_DIRTY;
	} else if ((cmp_p == 0 && DB_REDO(op) && argp->opcode == DELOVFL) ||
	    (cmp_n == 0 && DB_UNDO(op) && argp->opcode == PUTOVFL)) {
		/*
		 * Redo a delete or undo a create new page.  All we
		 * really need to do is change the LSN.
		 */
		flags = DB_MPOOL_DIRTY;
	}

	if (flags)
		LSN(pagep) = DB_REDO(op) ? *lsnp : argp->pagelsn;

	if ((ret = __memp_fput(mpf, pagep, flags)) != 0)
		goto out;
	pagep = NULL;

	/* Now do the prev page. */
ppage:	if (argp->prev_pgno != PGNO_INVALID) {
		REC_FGET(mpf, argp->prev_pgno, &pagep, npage);

		cmp_n = log_compare(lsnp, &LSN(pagep));
		cmp_p = log_compare(&LSN(pagep), &argp->prevlsn);
		CHECK_LSN(op, cmp_p, &LSN(pagep), &argp->prevlsn);
		flags = 0;

		if ((cmp_p == 0 && DB_REDO(op) && argp->opcode == PUTOVFL) ||
		    (cmp_n == 0 && DB_UNDO(op) && argp->opcode == DELOVFL)) {
			/* Redo a create new page or undo a delete new page. */
			pagep->next_pgno = argp->new_pgno;
			flags = DB_MPOOL_DIRTY;
		} else if ((cmp_p == 0 &&
		    DB_REDO(op) && argp->opcode == DELOVFL) ||
		    (cmp_n == 0 && DB_UNDO(op) && argp->opcode == PUTOVFL)) {
			/* Redo a delete or undo a create new page. */
			pagep->next_pgno = argp->next_pgno;
			flags = DB_MPOOL_DIRTY;
		}

		if (flags)
			LSN(pagep) = DB_REDO(op) ? *lsnp : argp->prevlsn;

		if ((ret = __memp_fput(mpf, pagep, flags)) != 0)
			goto out;
		pagep = NULL;
	}

	/* Now time to do the next page */
npage:	if (argp->next_pgno != PGNO_INVALID) {
		REC_FGET(mpf, argp->next_pgno, &pagep, done);

		cmp_n = log_compare(lsnp, &LSN(pagep));
		cmp_p = log_compare(&LSN(pagep), &argp->nextlsn);
		CHECK_LSN(op, cmp_p, &LSN(pagep), &argp->nextlsn);
		flags = 0;

		if ((cmp_p == 0 && DB_REDO(op) && argp->opcode == PUTOVFL) ||
		    (cmp_n == 0 && DB_UNDO(op) && argp->opcode == DELOVFL)) {
			/* Redo a create new page or undo a delete new page. */
			pagep->prev_pgno = argp->new_pgno;
			flags = DB_MPOOL_DIRTY;
		} else if ((cmp_p == 0 &&
		    DB_REDO(op) && argp->opcode == DELOVFL) ||
		    (cmp_n == 0 && DB_UNDO(op) && argp->opcode == PUTOVFL)) {
			/* Redo a delete or undo a create new page. */
			pagep->prev_pgno = argp->prev_pgno;
			flags = DB_MPOOL_DIRTY;
		}

		if (flags)
			LSN(pagep) = DB_REDO(op) ? *lsnp : argp->nextlsn;

		if ((ret = __memp_fput(mpf, pagep, flags)) != 0)
			goto out;
		pagep = NULL;
	}
done:	*lsnp = argp->prev_lsn;
	ret = 0;

out:	if (pagep != NULL)
		(void)__memp_fput(mpf, pagep, 0);
	REC_CLOSE;
}

/*
 * __ham_replace_recover --
 *	This log message refers to partial puts that are local to a single
 *	page.  You can think of them as special cases of the more general
 *	insdel log message.
 *
 * PUBLIC: int __ham_replace_recover
 * PUBLIC:    __P((DB_ENV *, DBT *, DB_LSN *, db_recops, void *));
 */
int
__ham_replace_recover(dbenv, dbtp, lsnp, op, info)
	DB_ENV *dbenv;
	DBT *dbtp;
	DB_LSN *lsnp;
	db_recops op;
	void *info;
{
	__ham_replace_args *argp;
	DB *file_dbp;
	DBC *dbc;
	DB_MPOOLFILE *mpf;
	DBT dbt;
	PAGE *pagep;
	u_int32_t flags;
	u_int32_t change;
	int cmp_n, cmp_p, is_plus, ret;
	u_int8_t *hk;

	pagep = NULL;
	COMPQUIET(info, NULL);

	REC_PRINT(__ham_replace_print);
	REC_INTRO(__ham_replace_read, 1);

	REC_FGET(mpf, argp->pgno, &pagep, done);

	cmp_n = log_compare(lsnp, &LSN(pagep));
	cmp_p = log_compare(&LSN(pagep), &argp->pagelsn);
	CHECK_LSN(op, cmp_p, &LSN(pagep), &argp->pagelsn);

	memset(&dbt, 0, sizeof(dbt));
	flags = 0;

	/*
	 * Before we know the direction of the transformation we will
	 * determine the size differential; then once we know if we are
	 * redoing or undoing, we'll adjust the sign (is_plus) appropriately.
	 */
	if (argp->newitem.size > argp->olditem.size) {
		change = argp->newitem.size - argp->olditem.size;
		is_plus = 1;
	} else {
		change = argp->olditem.size - argp->newitem.size;
		is_plus = 0;
	}
	if (cmp_p == 0 && DB_REDO(op)) {
		/* Reapply the change as specified. */
		dbt.data = argp->newitem.data;
		dbt.size = argp->newitem.size;
		LSN(pagep) = *lsnp;
		/*
		 * The is_plus flag is set properly to reflect
		 * newitem.size - olditem.size.
		 */
		flags = DB_MPOOL_DIRTY;
	} else if (cmp_n == 0 && DB_UNDO(op)) {
		/* Undo the already applied change. */
		dbt.data = argp->olditem.data;
		dbt.size = argp->olditem.size;
		/*
		 * Invert is_plus to reflect sign of
		 * olditem.size - newitem.size.
		 */
		is_plus = !is_plus;
		LSN(pagep) = argp->pagelsn;
		flags = DB_MPOOL_DIRTY;
	}

	if (flags) {
		__ham_onpage_replace(file_dbp, pagep,
		    argp->ndx, argp->off, change, is_plus, &dbt);
		if (argp->makedup) {
			hk = P_ENTRY(file_dbp, pagep, argp->ndx);
			if (DB_REDO(op))
				HPAGE_PTYPE(hk) = H_DUPLICATE;
			else
				HPAGE_PTYPE(hk) = H_KEYDATA;
		}