int dleaf_isinorder(BTREE, struct dleaf *leaf)
{
	struct group *gdict = (void *)leaf + btree->sb->blocksize;
	struct entry *edict = (void *)(gdict - leaf->groups);
	for (int grp = -1; grp >= -leaf->groups; grp--)
		for (int ent = -1, prevlimit = 0; ent >= -gdict[grp].count; prevlimit = edict[ent--].limit)
			if (edict[ent].limit < prevlimit)
				return 0;
	return 1;
}