return nil
	}
	*d = doc
	return nil
}

// key options
type options struct {
	ttl int64 // expiry in seconds
}

type iamWatchEvent struct {
	isCreated bool // !isCreated implies a delete event.
	keyPath   string
}

// iamCache contains in-memory cache of IAM data.
type iamCache struct {
	updatedAt time.Time

	// map of policy names to policy definitions

	setDriveCounts := make([]int, len(z.serverPools))
	for i := range z.serverPools {
		setDriveCounts[i] = z.serverPools[i].SetDriveCount()
	}
	return setDriveCounts
}

type serverPoolsAvailableSpace []poolAvailableSpace

type poolAvailableSpace struct {
	Index      int
	Available  uint64 // in bytes
	MaxUsedPct int    // Used disk percentage of most filled disk, rounded down.
}

	}
	var xl xlMetaV2
	err = xl.LoadOrConvert(buf)
	if err != nil {
		return err
	}
	foundDirs := make(map[string]struct{}, len(xl.versions))
	err = readDirFn(baseDir, func(name string, typ os.FileMode) error {
		if !typ.IsDir() {
			return nil
		}
		// See if directory has a UUID name.
		base := filepath.Base(name)
		_, err := uuid.Parse(base)
		if err == nil {
			foundDirs[base] = struct{}{}
		}

			// and SSE-S3 is specified do not preserve
			// the incoming etag.
			userDefined["etag"] = opts.PreserveETag
		}
	}

	// Guess content-type from the extension if possible.
	if userDefined["content-type"] == "" {
		userDefined["content-type"] = mimedb.TypeByExtension(path.Ext(object))
	}

	// if storageClass is standard no need to save it as part of metadata.