bt_verify.c

这是linux下运行的mysql软件包,可用于linux 下安装 php + mysql + apach 的网络配置

/*-
 * See the file LICENSE for redistribution information.
 *
 * Copyright (c) 1999-2002
 *	Sleepycat Software.  All rights reserved.
 *
 * $Id: bt_verify.c,v 1.76 2002/07/03 19:03:51 bostic Exp $
 */

#include "db_config.h"

#ifndef lint
static const char revid[] = "$Id: bt_verify.c,v 1.76 2002/07/03 19:03:51 bostic Exp $";
#endif /* not lint */

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

#include <string.h>
#endif

#include "db_int.h"
#include "dbinc/db_page.h"
#include "dbinc/db_verify.h"
#include "dbinc/btree.h"

static int __bam_safe_getdata __P((DB *, PAGE *, u_int32_t, int, DBT *, int *));
static int __bam_vrfy_inp __P((DB *, VRFY_DBINFO *, PAGE *, db_pgno_t,
    db_indx_t *, u_int32_t));
static int __bam_vrfy_treeorder __P((DB *, db_pgno_t, PAGE *, BINTERNAL *,
    BINTERNAL *, int (*)(DB *, const DBT *, const DBT *), u_int32_t));
static int __ram_vrfy_inp __P((DB *, VRFY_DBINFO *, PAGE *, db_pgno_t,
    db_indx_t *, u_int32_t));

#define	OKFLAGS	(DB_AGGRESSIVE | DB_NOORDERCHK | DB_SALVAGE)

/*
 * __bam_vrfy_meta --
 *	Verify the btree-specific part of a metadata page.
 *
 * PUBLIC: int __bam_vrfy_meta __P((DB *, VRFY_DBINFO *, BTMETA *,
 * PUBLIC:     db_pgno_t, u_int32_t));
 */
int
__bam_vrfy_meta(dbp, vdp, meta, pgno, flags)
	DB *dbp;
	VRFY_DBINFO *vdp;
	BTMETA *meta;
	db_pgno_t pgno;
	u_int32_t flags;
{
	VRFY_PAGEINFO *pip;
	int isbad, t_ret, ret;
	db_indx_t ovflsize;

	if ((ret = __db_vrfy_getpageinfo(vdp, pgno, &pip)) != 0)
		return (ret);

	isbad = 0;

	/*
	 * If VRFY_INCOMPLETE is not set, then we didn't come through
	 * __db_vrfy_pagezero and didn't incompletely
	 * check this page--we haven't checked it at all.
	 * Thus we need to call __db_vrfy_meta and check the common fields.
	 *
	 * If VRFY_INCOMPLETE is set, we've already done all the same work
	 * in __db_vrfy_pagezero, so skip the check.
	 */
	if (!F_ISSET(pip, VRFY_INCOMPLETE) &&
	    (ret = __db_vrfy_meta(dbp, vdp, &meta->dbmeta, pgno, flags)) != 0) {
		if (ret == DB_VERIFY_BAD)
			isbad = 1;
		else
			goto err;
	}

	/* bt_minkey:  must be >= 2; must produce sensible ovflsize */

	/* avoid division by zero */
	ovflsize = meta->minkey > 0 ?
	    B_MINKEY_TO_OVFLSIZE(dbp, meta->minkey, dbp->pgsize) : 0;

	if (meta->minkey < 2 ||
	    ovflsize > B_MINKEY_TO_OVFLSIZE(dbp, DEFMINKEYPAGE, dbp->pgsize)) {
		pip->bt_minkey = 0;
		isbad = 1;
		EPRINT((dbp->dbenv,
	    "Page %lu: nonsensical bt_minkey value %lu on metadata page",
		    (u_long)pgno, (u_long)meta->minkey));
	} else
		pip->bt_minkey = meta->minkey;

	/* bt_maxkey: no constraints (XXX: right?) */
	pip->bt_maxkey = meta->maxkey;

	/* re_len: no constraints on this (may be zero or huge--we make rope) */
	pip->re_len = meta->re_len;

	/*
	 * The root must not be current page or 0 and it must be within
	 * database.  If this metadata page is the master meta data page
	 * of the file, then the root page had better be page 1.
	 */
	pip->root = 0;
	if (meta->root == PGNO_INVALID ||
	    meta->root == pgno || !IS_VALID_PGNO(meta->root) ||
	    (pgno == PGNO_BASE_MD && meta->root != 1)) {
		isbad = 1;
		EPRINT((dbp->dbenv,
		    "Page %lu: nonsensical root page %lu on metadata page",
		    (u_long)pgno, (u_long)meta->root));
	} else
		pip->root = meta->root;

	/* Flags. */
	if (F_ISSET(&meta->dbmeta, BTM_RENUMBER))
		F_SET(pip, VRFY_IS_RRECNO);

	if (F_ISSET(&meta->dbmeta, BTM_SUBDB)) {
		/*
		 * If this is a master db meta page, it had better not have
		 * duplicates.
		 */
		if (F_ISSET(&meta->dbmeta, BTM_DUP) && pgno == PGNO_BASE_MD) {
			isbad = 1;
			EPRINT((dbp->dbenv,
"Page %lu: Btree metadata page has both duplicates and multiple databases",
			    (u_long)pgno));
		}
		F_SET(pip, VRFY_HAS_SUBDBS);
	}

	if (F_ISSET(&meta->dbmeta, BTM_DUP))
		F_SET(pip, VRFY_HAS_DUPS);
	if (F_ISSET(&meta->dbmeta, BTM_DUPSORT))
		F_SET(pip, VRFY_HAS_DUPSORT);
	if (F_ISSET(&meta->dbmeta, BTM_RECNUM))
		F_SET(pip, VRFY_HAS_RECNUMS);
	if (F_ISSET(pip, VRFY_HAS_RECNUMS) && F_ISSET(pip, VRFY_HAS_DUPS)) {
		EPRINT((dbp->dbenv,
    "Page %lu: Btree metadata page illegally has both recnums and dups",
		    (u_long)pgno));
		isbad = 1;
	}

	if (F_ISSET(&meta->dbmeta, BTM_RECNO)) {
		F_SET(pip, VRFY_IS_RECNO);
		dbp->type = DB_RECNO;
	} else if (F_ISSET(pip, VRFY_IS_RRECNO)) {
		isbad = 1;
		EPRINT((dbp->dbenv,
    "Page %lu: metadata page has renumber flag set but is not recno",
		    (u_long)pgno));
	}

	if (F_ISSET(pip, VRFY_IS_RECNO) && F_ISSET(pip, VRFY_HAS_DUPS)) {
		EPRINT((dbp->dbenv,
		    "Page %lu: recno metadata page specifies duplicates",
		    (u_long)pgno));
		isbad = 1;
	}

	if (F_ISSET(&meta->dbmeta, BTM_FIXEDLEN))
		F_SET(pip, VRFY_IS_FIXEDLEN);
	else if (pip->re_len > 0) {
		/*
		 * It's wrong to have an re_len if it's not a fixed-length
		 * database
		 */
		isbad = 1;
		EPRINT((dbp->dbenv,
		    "Page %lu: re_len of %lu in non-fixed-length database",
		    (u_long)pgno, (u_long)pip->re_len));
	}

	/*
	 * We do not check that the rest of the page is 0, because it may
	 * not be and may still be correct.
	 */

err:	if ((t_ret =
	    __db_vrfy_putpageinfo(dbp->dbenv, vdp, pip)) != 0 && ret == 0)
		ret = t_ret;
	return ((ret == 0 && isbad == 1) ? DB_VERIFY_BAD : ret);
}

/*
 * __ram_vrfy_leaf --
 *	Verify a recno leaf page.
 *
 * PUBLIC: int __ram_vrfy_leaf __P((DB *, VRFY_DBINFO *, PAGE *, db_pgno_t,
 * PUBLIC:     u_int32_t));
 */
int
__ram_vrfy_leaf(dbp, vdp, h, pgno, flags)
	DB *dbp;
	VRFY_DBINFO *vdp;
	PAGE *h;
	db_pgno_t pgno;
	u_int32_t flags;
{
	BKEYDATA *bk;
	VRFY_PAGEINFO *pip;
	db_indx_t i;
	int ret, t_ret, isbad;
	u_int32_t re_len_guess, len;

	isbad = 0;
	if ((ret = __db_vrfy_getpageinfo(vdp, pgno, &pip)) != 0)
		return (ret);

	if ((ret = __db_fchk(dbp->dbenv,
	    "__ram_vrfy_leaf", flags, OKFLAGS)) != 0)
		goto err;

	if (TYPE(h) != P_LRECNO) {
		/* We should not have been called. */
		TYPE_ERR_PRINT(dbp->dbenv, "__ram_vrfy_leaf", pgno, TYPE(h));
		DB_ASSERT(0);
		ret = EINVAL;
		goto err;
	}

	/*
	 * Verify (and, if relevant, save off) page fields common to
	 * all PAGEs.
	 */
	if ((ret = __db_vrfy_datapage(dbp, vdp, h, pgno, flags)) != 0) {
		if (ret == DB_VERIFY_BAD)
			isbad = 1;
		else
			goto err;
	}

	/*
	 * Verify inp[].  Return immediately if it returns DB_VERIFY_BAD;
	 * further checks are dangerous.
	 */
	if ((ret = __bam_vrfy_inp(dbp,
	    vdp, h, pgno, &pip->entries, flags)) != 0)
		goto err;

	if (F_ISSET(pip, VRFY_HAS_DUPS)) {
		EPRINT((dbp->dbenv,
		    "Page %lu: Recno database has dups", (u_long)pgno));
		ret = DB_VERIFY_BAD;
		goto err;
	}

	/*
	 * Walk through inp and see if the lengths of all the records are the
	 * same--if so, this may be a fixed-length database, and we want to
	 * save off this value.  We know inp to be safe if we've gotten this
	 * far.
	 */
	re_len_guess = 0;
	for (i = 0; i < NUM_ENT(h); i++) {
		bk = GET_BKEYDATA(dbp, h, i);
		/* KEYEMPTY.  Go on. */
		if (B_DISSET(bk->type))
			continue;
		if (bk->type == B_OVERFLOW)
			len = ((BOVERFLOW *)bk)->tlen;
		else if (bk->type == B_KEYDATA)
			len = bk->len;
		else {
			isbad = 1;
			EPRINT((dbp->dbenv,
			    "Page %lu: nonsensical type for item %lu",
			    (u_long)pgno, (u_long)i));
			continue;
		}
		if (re_len_guess == 0)
			re_len_guess = len;

		/*
		 * Is this item's len the same as the last one's?  If not,
		 * reset to 0 and break--we don't have a single re_len.
		 * Otherwise, go on to the next item.
		 */
		if (re_len_guess != len) {
			re_len_guess = 0;
			break;
		}
	}
	pip->re_len = re_len_guess;

	/* Save off record count. */
	pip->rec_cnt = NUM_ENT(h);

err:	if ((t_ret =
	    __db_vrfy_putpageinfo(dbp->dbenv, vdp, pip)) != 0 && ret == 0)
		ret = t_ret;
	return ((ret == 0 && isbad == 1) ? DB_VERIFY_BAD : ret);
}

/*
 * __bam_vrfy --
 *	Verify a btree leaf or internal page.
 *
 * PUBLIC: int __bam_vrfy __P((DB *, VRFY_DBINFO *, PAGE *, db_pgno_t,
 * PUBLIC:     u_int32_t));
 */
int
__bam_vrfy(dbp, vdp, h, pgno, flags)
	DB *dbp;
	VRFY_DBINFO *vdp;
	PAGE *h;
	db_pgno_t pgno;
	u_int32_t flags;
{
	VRFY_PAGEINFO *pip;
	int ret, t_ret, isbad;

	isbad = 0;
	if ((ret = __db_vrfy_getpageinfo(vdp, pgno, &pip)) != 0)
		return (ret);

	switch (TYPE(h)) {
	case P_IBTREE:
	case P_IRECNO:
	case P_LBTREE:
	case P_LDUP:
		break;
	default:
		TYPE_ERR_PRINT(dbp->dbenv, "__bam_vrfy", pgno, TYPE(h));
		DB_ASSERT(0);
		ret = EINVAL;
		goto err;
	}

	/*
	 * Verify (and, if relevant, save off) page fields common to
	 * all PAGEs.
	 */
	if ((ret = __db_vrfy_datapage(dbp, vdp, h, pgno, flags)) != 0) {
		if (ret == DB_VERIFY_BAD)
			isbad = 1;
		else
			goto err;
	}

	/*
	 * The record count is, on internal pages, stored in an overloaded
	 * next_pgno field.  Save it off;  we'll verify it when we check
	 * overall database structure.  We could overload the field
	 * in VRFY_PAGEINFO, too, but this seems gross, and space
	 * is not at such a premium.
	 */
	pip->rec_cnt = RE_NREC(h);

	/*
	 * Verify inp[].
	 */
	if (TYPE(h) == P_IRECNO) {
		if ((ret = __ram_vrfy_inp(dbp,
		    vdp, h, pgno, &pip->entries, flags)) != 0)
			goto err;
	} else if ((ret = __bam_vrfy_inp(dbp,
	    vdp, h, pgno, &pip->entries, flags)) != 0) {
		if (ret == DB_VERIFY_BAD)
			isbad = 1;
		else
			goto err;
		EPRINT((dbp->dbenv,
		    "Page %lu: item order check unsafe: skipping",
		    (u_long)pgno));
	} else if (!LF_ISSET(DB_NOORDERCHK) && (ret =
	    __bam_vrfy_itemorder(dbp, vdp, h, pgno, 0, 0, 0, flags)) != 0) {
		/*
		 * We know that the elements of inp are reasonable.
		 *
		 * Check that elements fall in the proper order.
		 */
		if (ret == DB_VERIFY_BAD)
			isbad = 1;
		else
			goto err;
	}

err:	if ((t_ret =
	    __db_vrfy_putpageinfo(dbp->dbenv, vdp, pip)) != 0 && ret == 0)
		ret = t_ret;
	return ((ret == 0 && isbad == 1) ? DB_VERIFY_BAD : ret);
}

/*
 * __ram_vrfy_inp --
 *	Verify that all entries in a P_IRECNO inp[] array are reasonable,
 *	and count them.  Note that P_LRECNO uses __bam_vrfy_inp;
 *	P_IRECNOs are a special, and simpler, case, since they have
 *	RINTERNALs rather than BKEYDATA/BINTERNALs.
 */
static int
__ram_vrfy_inp(dbp, vdp, h, pgno, nentriesp, flags)
	DB *dbp;
	VRFY_DBINFO *vdp;
	PAGE *h;
	db_pgno_t pgno;
	db_indx_t *nentriesp;
	u_int32_t flags;
{
	RINTERNAL *ri;
	VRFY_CHILDINFO child;
	VRFY_PAGEINFO *pip;
	int ret, t_ret, isbad;
	u_int32_t himark, i, offset, nentries;
	db_indx_t *inp;
	u_int8_t *pagelayout, *p;

	isbad = 0;
	memset(&child, 0, sizeof(VRFY_CHILDINFO));
	nentries = 0;
	pagelayout = NULL;

	if ((ret = __db_vrfy_getpageinfo(vdp, pgno, &pip)) != 0)
		return (ret);

	if (TYPE(h) != P_IRECNO) {
		TYPE_ERR_PRINT(dbp->dbenv, "__ram_vrfy_inp", pgno, TYPE(h));
		DB_ASSERT(0);
		ret = EINVAL;
		goto err;
	}

	himark = dbp->pgsize;
	if ((ret =
	    __os_malloc(dbp->dbenv, dbp->pgsize, &pagelayout)) != 0)
		goto err;
	memset(pagelayout, 0, dbp->pgsize);
	inp = P_INP(dbp, h);
	for (i = 0; i < NUM_ENT(h); i++) {
		if ((u_int8_t *)inp + i >= (u_int8_t *)h + himark) {
			EPRINT((dbp->dbenv,
			    "Page %lu: entries listing %lu overlaps data",
			    (u_long)pgno, (u_long)i));
			ret = DB_VERIFY_BAD;
			goto err;
		}
		offset = inp[i];
		/*
		 * Check that the item offset is reasonable:  it points
		 * somewhere after the inp array and before the end of the
		 * page.
		 */
		if (offset <= (u_int32_t)((u_int8_t *)inp + i -
		    (u_int8_t *)h) ||
		    offset > (u_int32_t)(dbp->pgsize - RINTERNAL_SIZE)) {
			isbad = 1;
			EPRINT((dbp->dbenv,
			    "Page %lu: bad offset %lu at index %lu",
			    (u_long)pgno, (u_long)offset, (u_long)i));
			continue;
		}

		/* Update the high-water mark (what HOFFSET should be) */
		if (offset < himark)
			himark = offset;

		nentries++;

		/* Make sure this RINTERNAL is not multiply referenced. */
		ri = GET_RINTERNAL(dbp, h, i);
		if (pagelayout[offset] == 0) {
			pagelayout[offset] = 1;
			child.pgno = ri->pgno;
			child.type = V_RECNO;
			child.nrecs = ri->nrecs;
			if ((ret = __db_vrfy_childput(vdp, pgno, &child)) != 0)
				goto err;
		} else {
			EPRINT((dbp->dbenv,
		"Page %lu: RINTERNAL structure at offset %lu referenced twice",
			    (u_long)pgno, (u_long)offset));
			isbad = 1;
		}
	}