* always under a lock.
     */
    private static final class SupplantableFuture implements Cancellable {
      private final ReentrantLock lock;

      @GuardedBy("lock")
      private Future<@Nullable Void> currentFuture;

      SupplantableFuture(ReentrantLock lock, Future<@Nullable Void> currentFuture) {
        this.lock = lock;
        this.currentFuture = currentFuture;
      }

			Op:   "open",
			Path: path,
			Err:  syscall.EINVAL,
		}
	}

	lock := syscall.Flock_t{
		Start:  0,
		Len:    0,
		Pid:    0,
		Type:   lockType,
		Whence: 0,
	}

	f, err := os.OpenFile(path, flag, perm)
	if err != nil {
		return nil, err
	}

	if err = syscall.FcntlFlock(f.Fd(), rlockType, &lock); err != nil {
		f.Close()
		if err == syscall.EAGAIN {
			err = ErrAlreadyLocked
		}

					}

					toUnLock = toUnLock[:0]
					for k, v := range l.lockMap {
						for _, lock := range v {
							toUnLock = append(toUnLock, dsync.LockArgs{Resources: []string{k}, UID: lock.UID, Owner: lock.Owner})
						}
					}
					start = time.Now()
					for _, lock := range toUnLock {
						ok, err := l.RUnlock(t.Context(), lock)
						if err != nil || !ok {
							t.Fatal(err)
						}
					}

		panic("Failed to acquire read lock")
	}
	// fmt.Println("1st read lock acquired, waiting...")

	drwm2 := NewDRWMutex(ds, "simplelock")
	ctx2, cancel2 := context.WithCancel(t.Context())
	if !drwm2.GetRLock(ctx2, cancel2, id, source, Options{Timeout: time.Second}) {
		panic("Failed to acquire read lock")
	}
	// fmt.Println("2nd read lock acquired, waiting...")

	go func() {

mn.it
mn.us
mo
mo-i-rana.no
mo-siemens.io
mo.cn
mo.it
mo.us
moareke.no
mobara.chiba.jp
mobi
mobi.gp
mobi.ke
mobi.ng
mobi.tz
mobile
mochizuki.nagano.jp
mock.pstmn.io
mod.gi
moda
modalen.no
modelling.aero
modelscape.com
modena.it
mods.jp
modum.no
modx.dev
moe
moi
moka.tochigi.jp
mokuren.ne.jp
mol.it
molde.no

```sh
aws s3api put-object --bucket testbucket --key lockme --object-lock-mode GOVERNANCE --object-lock-retain-until-date "2019-11-20"  --body /etc/issue
```

    for (int i = 0; i < reps; i++) {
      lock.lock();
      lock.unlock();
    }
  }

  @Benchmark
  void orderedPlainLocks(int reps) {
    lockAndUnlockNested(plainLocks, reps);
  }

  @Benchmark
  void orderedCycleDetectingLocks(int reps) {
    lockAndUnlockNested(detectingLocks, reps);
  }

  private static void lockAndUnlockNested(Lock[] locks, int reps) {

     * error-prone code like:
     *
     * Striped<Lock> stripedLock = Striped.lazyWeakXXX(...)'
     * Iterable<Lock> locks = stripedLock.bulkGet(keys);
     * for (Lock lock : locks) {
     *   lock.lock();
     * }
     * operation();
     * for (Lock lock : locks) {
     *   lock.unlock();
     * }
     *

import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;

/** Forwarding wrapper around a {@code Lock}. */
@J2ktIncompatible
@GwtIncompatible
abstract class ForwardingLock implements Lock {
  abstract Lock delegate();

  @Override
  public void lock() {
    delegate().lock();
  }

  @Override
  public void lockInterruptibly() throws InterruptedException {

import common.VersionedSettingsBranch
import configurations.BaseGradleBuildType
import configurations.applyDefaults
import configurations.applyTestDefaults
import io.mockk.every
import io.mockk.impl.annotations.MockK
import io.mockk.junit5.MockKExtension
import io.mockk.mockk
import io.mockk.slot
import jetbrains.buildServer.configs.kotlin.BuildStep
import jetbrains.buildServer.configs.kotlin.BuildSteps