prefixAll  string
}

// disconnectReader will ensure that no reads can take place on
// the upstream reader after close has been called.
type disconnectReader struct {
	r  io.Reader
	mu sync.Mutex
}

func (d *disconnectReader) Read(p []byte) (n int, err error) {
	d.mu.Lock()
	defer d.mu.Unlock()
	if d.r != nil {
		return d.r.Read(p)
	}
	return 0, errors.New("reader closed")
}

	// Deleted Buckets prefix.
	deletedBucketsPrefix = ".deleted"

	// ETag (hex encoded md5sum) of empty string.
	emptyETag = "d41d8cd98f00b204e9800998ecf8427e"
)

// Global object layer mutex, used for safely updating object layer.
var globalObjLayerMutex sync.RWMutex

// Global object layer, only accessed by globalObjectAPI.
var globalObjectAPI ObjectLayer

type storageOpts struct {
	cleanUp     bool

	"sync/atomic"
)

// Inspired from Golang sync.Once but it is only marked
// initialized when the provided function returns nil.

// Init represents the structure.
type Init struct {
	done uint32
	m    sync.Mutex
}

// Do is similar to sync.Once.Do - makes one successful
// call to the function. ie, it invokes the function
// if it is not successful yet.
func (l *Init) Do(f func() error) error {

	// into an SSE-S3 request. If enabled a valid, non-empty KMS
	// configuration must be present.
	globalAutoEncryption bool

	// Is compression enabled?
	globalCompressConfigMu sync.Mutex
	globalCompressConfig   compress.Config

	// Some standard object extensions which we strictly dis-allow for compression.

	var count int64
	h.mutex.RLock()
	defer h.mutex.RUnlock()

	for _, v := range h.scannedItemsMap {
		count += v
	}
	return count
}

// getScannedItemsMap - returns map of all scanned items against type
func (h *healSequence) getScannedItemsMap() map[madmin.HealItemType]int64 {
	h.mutex.RLock()
	defer h.mutex.RUnlock()

	// Make a copy before returning the value

		time.Sleep(time.Duration(d))
	}

	l.mutex.Lock()
	defer l.mutex.Unlock()
	reply = !l.lockNotFound
	return reply, nil
}

func (l *lockServer) ForceUnlock(args *LockArgs) (reply bool, err error) {
	if d := atomic.LoadInt64(&l.responseDelay); d != 0 {
		time.Sleep(time.Duration(d))
	}

	l.mutex.Lock()
	defer l.mutex.Unlock()
	if len(args.UID) != 0 {

	"math/rand"
	"sync"
	"time"

	"github.com/minio/pkg/v2/sync/errgroup"
)

func (er erasureObjects) getOnlineDisks() (newDisks []StorageAPI) {
	disks := er.getDisks()
	var wg sync.WaitGroup
	var mu sync.Mutex
	r := rand.New(rand.NewSource(time.Now().UnixNano()))
	for _, i := range r.Perm(len(disks)) {
		i := i
		wg.Add(1)
		go func() {
			defer wg.Done()
			if disks[i] == nil {
				return
			}

	srcCfg := getServerSystemCfg()
	clnts := newBootstrapRESTClients(endpointServerPools, gm)
	var onlineServers int
	var offlineEndpoints []error
	var incorrectConfigs []error
	var retries int
	var mu sync.Mutex
	for onlineServers < len(clnts)/2 {
		var wg sync.WaitGroup
		wg.Add(len(clnts))
		onlineServers = 0
		for _, clnt := range clnts {
			go func(clnt *bootstrapRESTClient) {
				defer wg.Done()

	TCPOptions      TCPOptions    // all the configurable TCP conn specific configurable options.
	ShutdownTimeout time.Duration // timeout used for graceful server shutdown.
	listenerMutex   sync.Mutex    // to guard 'listener' field.
	listener        *httpListener // HTTP listener for all 'Addrs' field.
	inShutdown      uint32        // indicates whether the server is in shutdown or not

		t.Fatal("Unlock timed out, which should not happen")
	case <-timer.C:
	}
}

// Borrowed from mutex_test.go
func HammerMutex(m *DRWMutex, loops int, cdone chan bool) {
	for i := 0; i < loops; i++ {
		m.Lock(id, source)
		m.Unlock(context.Background())
	}
	cdone <- true
}

// Borrowed from mutex_test.go
func TestMutex(t *testing.T) {
	loops := 200
	if testing.Short() {
		loops = 5
	}