}

// HashBorrower keeps track of borrowed hashers and allows to return them all.
type HashBorrower struct {
	pool     *sync.Pool
	borrowed []hash.Hash
}

// Borrow a single hasher.
func (h *HashBorrower) Borrow() hash.Hash {
	hasher := h.pool.Get().(hash.Hash)
	h.borrowed = append(h.borrowed, hasher)
	hasher.Reset()
	return hasher
}

	// https://github.com/dchest/siphash#usage
	k0, k1 := binary.LittleEndian.Uint64(id[0:8]), binary.LittleEndian.Uint64(id[8:16])
	sum64 := siphash.Hash(k0, k1, []byte(key))
	return int(sum64 % uint64(cardinality))
}

// hashOrder - hashes input key to return consistent
// hashed integer slice. Returned integer order is salted
// with an input key. This results in consistent order.

		return "SHA1"
	case c.Is(ChecksumSHA256):
		return "SHA256"
	case c.Is(ChecksumNone):
		return ""
	}
	return "invalid"
}

// Hasher returns a hasher corresponding to the checksum type.
// Returns nil if no checksum.
func (c ChecksumType) Hasher() hash.Hash {
	switch {
	case c.Is(ChecksumCRC32):
		return crc32.NewIEEE()
	case c.Is(ChecksumCRC32C):
		return crc32.New(crc32.MakeTable(crc32.Castagnoli))

	}
}

// KafkaSHA256 is a function that returns a crypto/sha256 hasher and should be used
// to create Client objects configured for SHA-256 hashing.
var KafkaSHA256 scram.HashGeneratorFcn = sha256.New

// KafkaSHA512 is a function that returns a crypto/sha512 hasher and should be used
// to create Client objects configured for SHA-512 hashing.
var KafkaSHA512 scram.HashGeneratorFcn = sha512.New

	"encoding/hex"

	"github.com/minio/minio/internal/hash/sha256"
)

// getSHA256Hash returns SHA-256 hash in hex encoding of given data.
func getSHA256Hash(data []byte) string {
	return hex.EncodeToString(getSHA256Sum(data))
}

// getSHA256Hash returns SHA-256 sum of given data.
func getSHA256Sum(data []byte) []byte {
	hash := sha256.New()
	hash.Write(data)
	return hash.Sum(nil)
}

	diskCount := 0
	for _, disk := range disks {
		if disk == nil {
			continue
		}
		diskCount++
	}
	return diskCount
}

// hashOrder - hashes input key to return consistent
// hashed integer slice. Returned integer order is salted
// with an input key. This results in consistent order.
// NOTE: collisions are fine, we are not looking for uniqueness
// in the slices returned.

	}

	if sipHashElement := hashKey("SIPMOD", "This will fail", 0, testUUID); sipHashElement != -1 {
		t.Errorf("Test: Expected \"-1\" but got \"%v\"", sipHashElement)
	}

	if sipHashElement := hashKey("UNKNOWN", "This will fail", 0, testUUID); sipHashElement != -1 {
		t.Errorf("Test: Expected \"-1\" but got \"%v\"", sipHashElement)
	}
}

// TestCrcHashMod - test crc hash.
func TestCrcHashMod(t *testing.T) {

- Choosing an erasure set for the object is decided during `PutObject()`, object names are used to find the right erasure set using the following pseudo code.

```go
// hashes the key returning an integer.
func sipHashMod(key string, cardinality int, id [16]byte) int {
        if cardinality <= 0 {
                return -1
        }
        sip := siphash.New(id[:])

	var wc io.WriteCloser
	wc = gzip.NewWriter(gw)
	if _, err = io.Copy(wc, r); err != nil {
		return err
	}

	if err = wc.Close(); err != nil {
		return err
	}

	// Persist to disk any caches.
	if err = gw.Sync(); err != nil {
		return err
	}

	// close everything before we delete.
	if err = gw.Close(); err != nil {
		return err
	}

	if err = r.Close(); err != nil {
		return err

	b.mu.Lock()
	defer b.mu.Unlock()
	for k, v := range b.caches {
		if time.Since(v.lastUpdate) > metacacheMaxRunningAge {
			v.delete(context.Background())
			continue
		}
		v.error = "Bucket deleted"
		v.status = scanStateError
		m.mu.Lock()
		m.trash[k] = v
		m.mu.Unlock()
	}
}

// deleteAll will delete all caches.
func (m *metacacheManager) deleteAll() {
	m.init.Do(m.initManager)