* 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;
      }

					}

					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)
						}
					}

            lock.readLock().unlock();
        }
    }

    /**
     * Get handle information by path
     * @param path the file path
     * @return the handle info or null if not found
     */
    public HandleInfo getHandleByPath(String path) {
        lock.readLock().lock();
        try {
            return handles.get(path);
        } finally {
            lock.readLock().unlock();
        }
    }

        }
      };

  private static final Supplier<Lock> LOCK_SUPPLER =
      new Supplier<Lock>() {
        @Override
        public Lock get() {
          return new ReentrantLock();
        }
      };

  private static final Supplier<Lock> FAIR_LOCK_SUPPLER =
      new Supplier<Lock>() {
        @Override
        public Lock get() {
          return new ReentrantLock(true);
        }
      };

        }
      };

  private static final Supplier<Lock> LOCK_SUPPLER =
      new Supplier<Lock>() {
        @Override
        public Lock get() {
          return new ReentrantLock();
        }
      };

  private static final Supplier<Lock> FAIR_LOCK_SUPPLER =
      new Supplier<Lock>() {
        @Override
        public Lock get() {
          return new ReentrantLock(true);
        }
      };

  enum Impl {
    EAGER {
      @Override
      Striped<Lock> get(int stripes) {
        return Striped.lock(stripes);
      }
    },
    LAZY_SMALL {
      @Override
      Striped<Lock> get(int stripes) {
        return new Striped.SmallLazyStriped<>(stripes, LOCK_SUPPLIER);
      }
    },
    LAZY_LARGE {
      @Override
      Striped<Lock> get(int stripes) {

 */
package jcifs.internal.smb2.lock;

import jcifs.Encodable;
import jcifs.internal.util.SMBUtil;

/**
 * SMB2 Lock data structure.
 *
 * This class represents a single lock element used in
 * SMB2 Lock requests for byte-range locking.
 *
 * @author mbechler
 */
public class Smb2Lock implements Encodable {

    /**
     * Flag indicating a shared lock that allows concurrent read access.
     */

### Locks

We have 3 different things that we synchronize on.

#### Http2Connection

This lock guards internal state of each connection. This lock is never held for blocking operations. That means that we acquire the lock, read or write a few fields and release the lock. No I/O and no application-layer callbacks.

#### Http2Stream

	c.mu.Lock()
	bucketIdx := c.nextCleanupBucket
	timeToExpire := time.Until(c.buckets[bucketIdx].newestEntry)
	// wait for newest entry to expire before cleanup without holding lock
	if timeToExpire > 0 {
		c.mu.Unlock()
		time.Sleep(timeToExpire)
		c.mu.Lock()
	}
	for _, ent := range c.buckets[bucketIdx].entries {
		c.removeElement(ent)
	}
	c.nextCleanupBucket = (c.nextCleanupBucket + 1) % numBuckets

    final Lock lock;

    LockingThread(Lock lock) {
      this.lock = lock;
    }

    @Override
    public void run() {
      lock.lock();
      try {
        locked.countDown();
        finishLatch.await(1, MINUTES);
      } catch (InterruptedException e) {
        fail(e.toString());
      } finally {
        lock.unlock();
      }
    }