db_vrfy.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

__db_vrfy_common(dbp, vdp, h, pgno, flags)
	DB *dbp;
	VRFY_DBINFO *vdp;
	PAGE *h;
	db_pgno_t pgno;
	u_int32_t flags;
{
	DB_ENV *dbenv;
	VRFY_PAGEINFO *pip;
	int ret, t_ret;
	u_int8_t *p;

	dbenv = dbp->dbenv;

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

	pip->pgno = pgno;
	F_CLR(pip, VRFY_IS_ALLZEROES);

	/*
	 * Hash expands the table by leaving some pages between the
	 * old last and the new last totally zeroed.  Its pgin function
	 * should fix things, but we might not be using that (e.g. if
	 * we're a subdatabase).
	 *
	 * Queue will create sparse files if sparse record numbers are used.
	 */
	if (pgno != 0 && PGNO(h) == 0) {
		for (p = (u_int8_t *)h; p < (u_int8_t *)h + dbp->pgsize; p++)
			if (*p != 0) {
				EPRINT((dbenv,
				    "Page %lu: partially zeroed page",
				    (u_long)pgno));
				ret = DB_VERIFY_BAD;
				goto err;
			}
		/*
		 * It's totally zeroed;  mark it as a hash, and we'll
		 * check that that makes sense structurally later.
		 * (The queue verification doesn't care, since queues
		 * don't really have much in the way of structure.)
		 */
		pip->type = P_HASH;
		F_SET(pip, VRFY_IS_ALLZEROES);
		ret = 0;
		goto err;	/* well, not really an err. */
	}

	if (PGNO(h) != pgno) {
		EPRINT((dbenv, "Page %lu: bad page number %lu",
		    (u_long)pgno, (u_long)h->pgno));
		ret = DB_VERIFY_BAD;
	}

	if (!__db_is_valid_pagetype(h->type)) {
		EPRINT((dbenv, "Page %lu: bad page type %lu",
		    (u_long)pgno, (u_long)h->type));
		ret = DB_VERIFY_BAD;
	}
	pip->type = h->type;

err:	if ((t_ret = __db_vrfy_putpageinfo(dbenv, vdp, pip)) != 0 && ret == 0)
		ret = t_ret;

	return (ret);
}

/*
 * __db_vrfy_invalid --
 *	Verify P_INVALID page.
 *	(Yes, there's not much to do here.)
 */
static int
__db_vrfy_invalid(dbp, vdp, h, pgno, flags)
	DB *dbp;
	VRFY_DBINFO *vdp;
	PAGE *h;
	db_pgno_t pgno;
	u_int32_t flags;
{
	DB_ENV *dbenv;
	VRFY_PAGEINFO *pip;
	int ret, t_ret;

	dbenv = dbp->dbenv;

	if ((ret = __db_vrfy_getpageinfo(vdp, pgno, &pip)) != 0)
		return (ret);
	pip->next_pgno = pip->prev_pgno = 0;

	if (!IS_VALID_PGNO(NEXT_PGNO(h))) {
		EPRINT((dbenv, "Page %lu: invalid next_pgno %lu",
		    (u_long)pgno, (u_long)NEXT_PGNO(h)));
		ret = DB_VERIFY_BAD;
	} else
		pip->next_pgno = NEXT_PGNO(h);

	if ((t_ret = __db_vrfy_putpageinfo(dbenv, vdp, pip)) != 0 && ret == 0)
		ret = t_ret;
	return (ret);
}

/*
 * __db_vrfy_datapage --
 *	Verify elements common to data pages (P_HASH, P_LBTREE,
 *	P_IBTREE, P_IRECNO, P_LRECNO, P_OVERFLOW, P_DUPLICATE)--i.e.,
 *	those defined in the PAGE structure.
 *
 *	Called from each of the per-page routines, after the
 *	all-page-type-common elements of pip have been verified and filled
 *	in.
 *
 * PUBLIC: int __db_vrfy_datapage
 * PUBLIC:     __P((DB *, VRFY_DBINFO *, PAGE *, db_pgno_t, u_int32_t));
 */
int
__db_vrfy_datapage(dbp, vdp, h, pgno, flags)
	DB *dbp;
	VRFY_DBINFO *vdp;
	PAGE *h;
	db_pgno_t pgno;
	u_int32_t flags;
{
	DB_ENV *dbenv;
	VRFY_PAGEINFO *pip;
	int isbad, ret, t_ret;

	dbenv = dbp->dbenv;

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

	/*
	 * prev_pgno and next_pgno:  store for inter-page checks,
	 * verify that they point to actual pages and not to self.
	 *
	 * !!!
	 * Internal btree pages do not maintain these fields (indeed,
	 * they overload them).  Skip.
	 */
	if (TYPE(h) != P_IBTREE && TYPE(h) != P_IRECNO) {
		if (!IS_VALID_PGNO(PREV_PGNO(h)) || PREV_PGNO(h) == pip->pgno) {
			isbad = 1;
			EPRINT((dbenv, "Page %lu: invalid prev_pgno %lu",
			    (u_long)pip->pgno, (u_long)PREV_PGNO(h)));
		}
		if (!IS_VALID_PGNO(NEXT_PGNO(h)) || NEXT_PGNO(h) == pip->pgno) {
			isbad = 1;
			EPRINT((dbenv, "Page %lu: invalid next_pgno %lu",
			    (u_long)pip->pgno, (u_long)NEXT_PGNO(h)));
		}
		pip->prev_pgno = PREV_PGNO(h);
		pip->next_pgno = NEXT_PGNO(h);
	}

	/*
	 * Verify the number of entries on the page.
	 * There is no good way to determine if this is accurate;  the
	 * best we can do is verify that it's not more than can, in theory,
	 * fit on the page.  Then, we make sure there are at least
	 * this many valid elements in inp[], and hope that this catches
	 * most cases.
	 */
	if (TYPE(h) != P_OVERFLOW) {
		if (BKEYDATA_PSIZE(0) * NUM_ENT(h) > dbp->pgsize) {
			isbad = 1;
			EPRINT((dbenv, "Page %lu: too many entries: %lu",
			    (u_long)pgno, (u_long)NUM_ENT(h)));
		}
		pip->entries = NUM_ENT(h);
	}

	/*
	 * btree level.  Should be zero unless we're a btree;
	 * if we are a btree, should be between LEAFLEVEL and MAXBTREELEVEL,
	 * and we need to save it off.
	 */
	switch (TYPE(h)) {
	case P_IBTREE:
	case P_IRECNO:
		if (LEVEL(h) < LEAFLEVEL + 1 || LEVEL(h) > MAXBTREELEVEL) {
			isbad = 1;
			EPRINT((dbenv, "Page %lu: bad btree level %lu",
			    (u_long)pgno, (u_long)LEVEL(h)));
		}
		pip->bt_level = LEVEL(h);
		break;
	case P_LBTREE:
	case P_LDUP:
	case P_LRECNO:
		if (LEVEL(h) != LEAFLEVEL) {
			isbad = 1;
			EPRINT((dbenv,
			    "Page %lu: btree leaf page has incorrect level %lu",
			    (u_long)pgno, (u_long)LEVEL(h)));
		}
		break;
	default:
		if (LEVEL(h) != 0) {
			isbad = 1;
			EPRINT((dbenv,
			    "Page %lu: nonzero level %lu in non-btree database",
			    (u_long)pgno, (u_long)LEVEL(h)));
		}
		break;
	}

	/*
	 * Even though inp[] occurs in all PAGEs, we look at it in the
	 * access-method-specific code, since btree and hash treat
	 * item lengths very differently, and one of the most important
	 * things we want to verify is that the data--as specified
	 * by offset and length--cover the right part of the page
	 * without overlaps, gaps, or violations of the page boundary.
	 */
	if ((t_ret = __db_vrfy_putpageinfo(dbenv, vdp, pip)) != 0 && ret == 0)
		ret = t_ret;

	return ((ret == 0 && isbad == 1) ? DB_VERIFY_BAD : ret);
}

/*
 * __db_vrfy_meta--
 *	Verify the access-method common parts of a meta page, using
 *	normal mpool routines.
 *
 * PUBLIC: int __db_vrfy_meta
 * PUBLIC:     __P((DB *, VRFY_DBINFO *, DBMETA *, db_pgno_t, u_int32_t));
 */
int
__db_vrfy_meta(dbp, vdp, meta, pgno, flags)
	DB *dbp;
	VRFY_DBINFO *vdp;
	DBMETA *meta;
	db_pgno_t pgno;
	u_int32_t flags;
{
	DB_ENV *dbenv;
	DBTYPE dbtype, magtype;
	VRFY_PAGEINFO *pip;
	int isbad, ret, t_ret;

	isbad = 0;
	dbenv = dbp->dbenv;

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

	/* type plausible for a meta page */
	switch (meta->type) {
	case P_BTREEMETA:
		dbtype = DB_BTREE;
		break;
	case P_HASHMETA:
		dbtype = DB_HASH;
		break;
	case P_QAMMETA:
		dbtype = DB_QUEUE;
		break;
	default:
		/* The verifier should never let us get here. */
		DB_ASSERT(0);
		ret = EINVAL;
		goto err;
	}

	/* magic number valid */
	if (!__db_is_valid_magicno(meta->magic, &magtype)) {
		isbad = 1;
		EPRINT((dbenv,
		    "Page %lu: invalid magic number", (u_long)pgno));
	}
	if (magtype != dbtype) {
		isbad = 1;
		EPRINT((dbenv,
		    "Page %lu: magic number does not match database type",
		    (u_long)pgno));
	}

	/* version */
	if ((dbtype == DB_BTREE &&
	    (meta->version > DB_BTREEVERSION ||
	    meta->version < DB_BTREEOLDVER)) ||
	    (dbtype == DB_HASH &&
	    (meta->version > DB_HASHVERSION ||
	    meta->version < DB_HASHOLDVER)) ||
	    (dbtype == DB_QUEUE &&
	    (meta->version > DB_QAMVERSION ||
	    meta->version < DB_QAMOLDVER))) {
		isbad = 1;
		EPRINT((dbenv,
    "Page %lu: unsupported database version %lu; extraneous errors may result",
		    (u_long)pgno, (u_long)meta->version));
	}

	/* pagesize */
	if (meta->pagesize != dbp->pgsize) {
		isbad = 1;
		EPRINT((dbenv, "Page %lu: invalid pagesize %lu",
		    (u_long)pgno, (u_long)meta->pagesize));
	}

	/* free list */
	/*
	 * If this is not the main, master-database meta page, it
	 * should not have a free list.
	 */
	if (pgno != PGNO_BASE_MD && meta->free != PGNO_INVALID) {
		isbad = 1;
		EPRINT((dbenv,
		    "Page %lu: nonempty free list on subdatabase metadata page",
		    (u_long)pgno));
	}

	/* Can correctly be PGNO_INVALID--that's just the end of the list. */
	if (meta->free != PGNO_INVALID && IS_VALID_PGNO(meta->free))
		pip->free = meta->free;
	else if (!IS_VALID_PGNO(meta->free)) {
		isbad = 1;
		EPRINT((dbenv,
		    "Page %lu: nonsensical free list pgno %lu",
		    (u_long)pgno, (u_long)meta->free));
	}

	/*
	 * We have now verified the common fields of the metadata page.
	 * Clear the flag that told us they had been incompletely checked.
	 */
	F_CLR(pip, VRFY_INCOMPLETE);

err:	if ((t_ret = __db_vrfy_putpageinfo(dbenv, vdp, pip)) != 0 && ret == 0)
		ret = t_ret;

	return ((ret == 0 && isbad == 1) ? DB_VERIFY_BAD : ret);
}

/*
 * __db_vrfy_freelist --
 *	Walk free list, checking off pages and verifying absence of
 *	loops.
 */
static int
__db_vrfy_freelist(dbp, vdp, meta, flags)
	DB *dbp;
	VRFY_DBINFO *vdp;
	db_pgno_t meta;
	u_int32_t flags;
{
	DB *pgset;
	DB_ENV *dbenv;
	VRFY_PAGEINFO *pip;
	db_pgno_t cur_pgno, next_pgno;
	int p, ret, t_ret;

	pgset = vdp->pgset;
	DB_ASSERT(pgset != NULL);
	dbenv = dbp->dbenv;

	if ((ret = __db_vrfy_getpageinfo(vdp, meta, &pip)) != 0)
		return (ret);
	for (next_pgno = pip->free;
	    next_pgno != PGNO_INVALID; next_pgno = pip->next_pgno) {
		cur_pgno = pip->pgno;
		if ((ret = __db_vrfy_putpageinfo(dbenv, vdp, pip)) != 0)
			return (ret);

		/* This shouldn't happen, but just in case. */
		if (!IS_VALID_PGNO(next_pgno)) {
			EPRINT((dbenv,
			    "Page %lu: invalid next_pgno %lu on free list page",
			    (u_long)cur_pgno, (u_long)next_pgno));
			return (DB_VERIFY_BAD);
		}

		/* Detect cycles. */
		if ((ret = __db_vrfy_pgset_get(pgset, next_pgno, &p)) != 0)
			return (ret);
		if (p != 0) {
			EPRINT((dbenv,
		    "Page %lu: page %lu encountered a second time on free list",
			    (u_long)cur_pgno, (u_long)next_pgno));
			return (DB_VERIFY_BAD);
		}
		if ((ret = __db_vrfy_pgset_inc(pgset, next_pgno)) != 0)
			return (ret);

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

		if (pip->type != P_INVALID) {
			EPRINT((dbenv,
			    "Page %lu: non-invalid page %lu on free list",
			    (u_long)cur_pgno, (u_long)next_pgno));
			ret = DB_VERIFY_BAD;	  /* unsafe to continue */
			break;
		}
	}

	if ((t_ret = __db_vrfy_putpageinfo(dbenv, vdp, pip)) != 0)
		ret = t_ret;
	return (ret);
}

/*
 * __db_vrfy_subdbs --
 *	Walk the known-safe master database of subdbs with a cursor,
 *	verifying the structure of each subdatabase we encounter.
 */
static int
__db_vrfy_subdbs(dbp, vdp, dbname, flags)
	DB *dbp;
	VRFY_DBINFO *vdp;
	const char *dbname;
	u_int32_t flags;
{
	DB *mdbp;
	DBC *dbc;
	DBT key, data;
	DB_ENV *dbenv;
	VRFY_PAGEINFO *pip;
	db_pgno_t meta_pgno;
	int ret, t_ret, isbad;
	u_int8_t type;

	isbad = 0;
	dbc = NULL;
	dbenv = dbp->dbenv;

	if ((ret =
	    __db_master_open(dbp, NULL, dbname, DB_RDONLY, 0, &mdbp)) != 0)
		return (ret);

	if ((ret = __db_icursor(mdbp,
	    NULL, DB_BTREE, PGNO_INVALID, 0, DB_LOCK_INVALIDID, &dbc)) != 0)
		goto err;

	memset(&key, 0, sizeof(key));
	memset(&data, 0, sizeof(data));
	while ((ret = dbc->c_get(dbc, &key, &data, DB_NEXT)) == 0) {
		if (data.size != sizeof(db_pgno_t)) {
			EPRINT((dbenv,
			    "Subdatabase entry not page-number size"));
			isbad = 1;
			goto err;
		}
		memcpy(&meta_pgno, data.data, data.size);
		/*
		 * Subdatabase meta pgnos are stored in network byte
		 * order for cross-endian compatibility.  Swap if appropriate.
		 */
		DB_NTOHL(&meta_pgno);
		if (meta_pgno == PGNO_INVALID || meta_pgno > vdp->last_pgno) {
			EPRINT((dbenv,
		    "Subdatabase entry references invalid page %lu",
			    (u_long)meta_pgno));
			isbad = 1;
			goto err;
		}
		if ((ret = __db_vrfy_getpageinfo(vdp, meta_pgno, &pip)) != 0)
			goto err;
		type = pip->type;
		if ((ret = __db_vrfy_putpageinfo(dbenv, vdp, pip)) != 0)
			goto err;
		switch (type) {
		case P_BTREEMETA:
			if ((ret = __bam_vrfy_structure(
			    dbp, vdp, meta_pgno, flags)) != 0) {
				if (ret == DB_VERIFY_BAD)
					isbad = 1;
				else
					goto err;
			}
			break;
		case P_HASHMETA:
			if ((ret = __ham_vrfy_structure(
			    dbp, vdp, meta_pgno, flags)) != 0) {
				if (ret == DB_VERIFY_BAD)
					isbad = 1;
				else
					goto err;
			}
			break;
		case P_QAMMETA:
		default:
			EPRINT((dbenv,
		    "Subdatabase entry references page %lu of invalid type %lu",
			    (u_long)meta_pgno, (u_long)type));
			ret = DB_VERIFY_BAD;
			goto err;
			/* NOTREACHED */
		}