var i = 1<<s                   // 1 has type int
var j int32 = 1<<s             // 1 has type int32; j == 0
var k = uint64(1<<s)           // 1 has type uint64; k == 1<<33
var m int = 1.0<<s             // 1.0 has type int; m == 1<<33
var n = 1.0<<s == j            // 1.0 has type int32; n == true
var o = 1<<s == 2<<s           // 1 and 2 have type int; o == false

	name              string
	parent            *dataUsageHash
	objectHealProbDiv uint32
}

type folderScanner struct {
	root        string
	getSize     getSizeFn
	oldCache    dataUsageCache
	newCache    dataUsageCache
	updateCache dataUsageCache

	dataUsageScannerDebug bool
	healObjectSelect      uint32 // Do a heal check on an object once every n cycles. Must divide into healFolderInclude

	// Locking operations on object.
	NewNSLock(bucket string, objects ...string) RWLocker

	// Storage operations.
	Shutdown(context.Context) error
	NSScanner(ctx context.Context, updates chan<- DataUsageInfo, wantCycle uint32, scanMode madmin.HealScanMode) error
	BackendInfo() madmin.BackendInfo
	Legacy() bool // Only returns true for deployments which use CRCMOD as its object distribution algorithm.

// chance the file doesn't exist yet.
var (
	randN  uint32
	randmu sync.Mutex
)

// Temp files created in default Tmp dir
var globalTestTmpDir = os.TempDir()

// reseed - returns a new seed every time the function is called.
func reseed() uint32 {
	return uint32(time.Now().UnixNano() + int64(os.Getpid()))
}

}

func crcHashMod(key string, cardinality int) int {
	if cardinality <= 0 {
		return -1
	}
	keyCrc := crc32.Checksum([]byte(key), crc32.IEEETable)
	return int(keyCrc % uint32(cardinality))
}

func hashKey(algo string, key string, cardinality int, id [16]byte) int {
	switch algo {
	case formatErasureVersionV2DistributionAlgoV1:
		return crcHashMod(key, cardinality)

	return globalNotificationSys.StorageInfo(z, metrics)
}

func (z *erasureServerPools) NSScanner(ctx context.Context, updates chan<- DataUsageInfo, wantCycle uint32, healScanMode madmin.HealScanMode) error {
	// Updates must be closed before we return.
	defer xioutil.SafeClose(updates)

	ctx, cancel := context.WithCancel(ctx)
	defer cancel()

	var wg sync.WaitGroup