bt_stat.c

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	top = NUM_ENT(h);
	inp = P_INP(dbp, h);

	switch (TYPE(h)) {
	case P_IBTREE:
	case P_IRECNO:
		++sp->bt_int_pg;
		sp->bt_int_pgfree += P_FREESPACE(dbp, h);
		break;
	case P_LBTREE:
		if (top == 0)
			++sp->bt_empty_pg;

		/* Correct for on-page duplicates and deleted items. */
		for (indx = 0; indx < top; indx += P_INDX) {
			type = GET_BKEYDATA(dbp, h, indx + O_INDX)->type;
			/* Ignore deleted items. */
			if (B_DISSET(type))
				continue;

			/* Ignore duplicate keys. */
			if (indx + P_INDX >= top ||
			    inp[indx] != inp[indx + P_INDX])
				++sp->bt_nkeys;

			/* Ignore off-page duplicates. */
			if (B_TYPE(type) != B_DUPLICATE)
				++sp->bt_ndata;
		}

		++sp->bt_leaf_pg;
		sp->bt_leaf_pgfree += P_FREESPACE(dbp, h);
		break;
	case P_LRECNO:
		if (top == 0)
			++sp->bt_empty_pg;

		/*
		 * If walking a recno tree, then each of these items is a key.
		 * Otherwise, we're walking an off-page duplicate set.
		 */
		if (dbp->type == DB_RECNO) {
			/*
			 * Correct for deleted items in non-renumbering Recno
			 * databases.
			 */
			if (F_ISSET(dbp, DB_AM_RENUMBER)) {
				sp->bt_nkeys += top;
				sp->bt_ndata += top;
			} else
				for (indx = 0; indx < top; indx += O_INDX) {
					type = GET_BKEYDATA(dbp, h, indx)->type;
					if (!B_DISSET(type)) {
						++sp->bt_ndata;
						++sp->bt_nkeys;
					}
				}

			++sp->bt_leaf_pg;
			sp->bt_leaf_pgfree += P_FREESPACE(dbp, h);
		} else {
			sp->bt_ndata += top;

			++sp->bt_dup_pg;
			sp->bt_dup_pgfree += P_FREESPACE(dbp, h);
		}
		break;
	case P_LDUP:
		if (top == 0)
			++sp->bt_empty_pg;

		/* Correct for deleted items. */
		for (indx = 0; indx < top; indx += O_INDX)
			if (!B_DISSET(GET_BKEYDATA(dbp, h, indx)->type))
				++sp->bt_ndata;

		++sp->bt_dup_pg;
		sp->bt_dup_pgfree += P_FREESPACE(dbp, h);
		break;
	case P_OVERFLOW:
		++sp->bt_over_pg;
		sp->bt_over_pgfree += P_OVFLSPACE(dbp, dbp->pgsize, h);
		break;
	default:
		return (__db_pgfmt(dbp->dbenv, h->pgno));
	}
	return (0);
}

/*
 * __bam_print_cursor --
 *	Display the current internal cursor.
 *
 * PUBLIC: void __bam_print_cursor __P((DBC *));
 */
void
__bam_print_cursor(dbc)
	DBC *dbc;
{
	static const FN fn[] = {
		{ C_DELETED,	"C_DELETED" },
		{ C_RECNUM,	"C_RECNUM" },
		{ C_RENUMBER,	"C_RENUMBER" },
		{ 0,		NULL }
	};
	DB_ENV *dbenv;
	BTREE_CURSOR *cp;

	dbenv = dbc->dbp->dbenv;
	cp = (BTREE_CURSOR *)dbc->internal;

	STAT_ULONG("Overflow size", cp->ovflsize);
	if (dbc->dbtype == DB_RECNO)
		STAT_ULONG("Recno", cp->recno);
	STAT_ULONG("Order", cp->order);
	__db_prflags(dbenv, NULL, cp->flags, fn, NULL, "\tInternal Flags");
}

#else /* !HAVE_STATISTICS */

int
__bam_stat(dbc, spp, flags)
	DBC *dbc;
	void *spp;
	u_int32_t flags;
{
	COMPQUIET(spp, NULL);
	COMPQUIET(flags, 0);

	return (__db_stat_not_built(dbc->dbp->dbenv));
}

int
__bam_stat_print(dbc, flags)
	DBC *dbc;
	u_int32_t flags;
{
	COMPQUIET(flags, 0);

	return (__db_stat_not_built(dbc->dbp->dbenv));
}
#endif

/*
 * __bam_key_range --
 *	Return proportion of keys relative to given key.  The numbers are
 *	slightly skewed due to on page duplicates.
 *
 * PUBLIC: int __bam_key_range __P((DBC *, DBT *, DB_KEY_RANGE *, u_int32_t));
 */
int
__bam_key_range(dbc, dbt, kp, flags)
	DBC *dbc;
	DBT *dbt;
	DB_KEY_RANGE *kp;
	u_int32_t flags;
{
	BTREE_CURSOR *cp;
	EPG *sp;
	double factor;
	int exact, ret;

	COMPQUIET(flags, 0);

	if ((ret = __bam_search(dbc, PGNO_INVALID,
	    dbt, S_STK_ONLY, 1, NULL, &exact)) != 0)
		return (ret);

	cp = (BTREE_CURSOR *)dbc->internal;
	kp->less = kp->greater = 0.0;

	factor = 1.0;
	/* Correct the leaf page. */
	cp->csp->entries /= 2;
	cp->csp->indx /= 2;
	for (sp = cp->sp; sp <= cp->csp; ++sp) {
		/*
		 * At each level we know that pages greater than indx contain
		 * keys greater than what we are looking for and those less
		 * than indx are less than.  The one pointed to by indx may
		 * have some less, some greater or even equal.  If indx is
		 * equal to the number of entries, then the key is out of range
		 * and everything is less.
		 */
		if (sp->indx == 0)
			kp->greater += factor * (sp->entries - 1)/sp->entries;
		else if (sp->indx == sp->entries)
			kp->less += factor;
		else {
			kp->less += factor * sp->indx / sp->entries;
			kp->greater += factor *
			    ((sp->entries - sp->indx) - 1) / sp->entries;
		}
		factor *= 1.0/sp->entries;
	}

	/*
	 * If there was an exact match then assign 1 n'th to the key itself.
	 * Otherwise that factor belongs to those greater than the key, unless
	 * the key was out of range.
	 */
	if (exact)
		kp->equal = factor;
	else {
		if (kp->less != 1)
			kp->greater += factor;
		kp->equal = 0;
	}

	BT_STK_CLR(cp);

	return (0);
}

/*
 * __bam_traverse --
 *	Walk a Btree database.
 *
 * PUBLIC: int __bam_traverse __P((DBC *, db_lockmode_t,
 * PUBLIC:     db_pgno_t, int (*)(DB *, PAGE *, void *, int *), void *));
 */
int
__bam_traverse(dbc, mode, root_pgno, callback, cookie)
	DBC *dbc;
	db_lockmode_t mode;
	db_pgno_t root_pgno;
	int (*callback)__P((DB *, PAGE *, void *, int *));
	void *cookie;
{
	BINTERNAL *bi;
	BKEYDATA *bk;
	DB *dbp;
	DB_LOCK lock;
	DB_MPOOLFILE *mpf;
	PAGE *h;
	RINTERNAL *ri;
	db_indx_t indx, *inp;
	int already_put, ret, t_ret;

	dbp = dbc->dbp;
	mpf = dbp->mpf;
	already_put = 0;

	if ((ret = __db_lget(dbc, 0, root_pgno, mode, 0, &lock)) != 0)
		return (ret);
	if ((ret = __memp_fget(mpf, &root_pgno, 0, &h)) != 0) {
		(void)__TLPUT(dbc, lock);
		return (ret);
	}

	switch (TYPE(h)) {
	case P_IBTREE:
		for (indx = 0; indx < NUM_ENT(h); indx += O_INDX) {
			bi = GET_BINTERNAL(dbp, h, indx);
			if (B_TYPE(bi->type) == B_OVERFLOW &&
			    (ret = __db_traverse_big(dbp,
			    ((BOVERFLOW *)bi->data)->pgno,
			    callback, cookie)) != 0)
				goto err;
			if ((ret = __bam_traverse(
			    dbc, mode, bi->pgno, callback, cookie)) != 0)
				goto err;
		}
		break;
	case P_IRECNO:
		for (indx = 0; indx < NUM_ENT(h); indx += O_INDX) {
			ri = GET_RINTERNAL(dbp, h, indx);
			if ((ret = __bam_traverse(
			    dbc, mode, ri->pgno, callback, cookie)) != 0)
				goto err;
		}
		break;
	case P_LBTREE:
		inp = P_INP(dbp, h);
		for (indx = 0; indx < NUM_ENT(h); indx += P_INDX) {
			bk = GET_BKEYDATA(dbp, h, indx);
			if (B_TYPE(bk->type) == B_OVERFLOW &&
			    (indx + P_INDX >= NUM_ENT(h) ||
			    inp[indx] != inp[indx + P_INDX])) {
				if ((ret = __db_traverse_big(dbp,
				    GET_BOVERFLOW(dbp, h, indx)->pgno,
				    callback, cookie)) != 0)
					goto err;
			}
			bk = GET_BKEYDATA(dbp, h, indx + O_INDX);
			if (B_TYPE(bk->type) == B_DUPLICATE &&
			    (ret = __bam_traverse(dbc, mode,
			    GET_BOVERFLOW(dbp, h, indx + O_INDX)->pgno,
			    callback, cookie)) != 0)
				goto err;
			if (B_TYPE(bk->type) == B_OVERFLOW &&
			    (ret = __db_traverse_big(dbp,
			    GET_BOVERFLOW(dbp, h, indx + O_INDX)->pgno,
			    callback, cookie)) != 0)
				goto err;
		}
		break;
	case P_LDUP:
	case P_LRECNO:
		for (indx = 0; indx < NUM_ENT(h); indx += O_INDX) {
			bk = GET_BKEYDATA(dbp, h, indx);
			if (B_TYPE(bk->type) == B_OVERFLOW &&
			    (ret = __db_traverse_big(dbp,
			    GET_BOVERFLOW(dbp, h, indx)->pgno,
			    callback, cookie)) != 0)
				goto err;
		}
		break;
	default:
		return (__db_pgfmt(dbp->dbenv, h->pgno));
	}

	ret = callback(dbp, h, cookie, &already_put);

err:	if (!already_put && (t_ret = __memp_fput(mpf, h, 0)) != 0 && ret == 0)
		ret = t_ret;
	if ((t_ret = __TLPUT(dbc, lock)) != 0 && ret == 0)
		ret = t_ret;

	return (ret);
}