}

func (fdmu *FDMutex) ReadLock() bool {
	return fdmu.fdmu.rwlock(true)
}

func (fdmu *FDMutex) ReadUnlock() bool {
	return fdmu.fdmu.rwunlock(true)
}

func (fdmu *FDMutex) WriteLock() bool {
	return fdmu.fdmu.rwlock(false)
}

func (fdmu *FDMutex) WriteUnlock() bool {
	return fdmu.fdmu.rwunlock(false)

    Lock readLock = striped.get(key).readLock();
    WeakReference<Object> garbage = new WeakReference<>(new Object());
    GcFinalization.awaitClear(garbage);
    Lock writeLock = striped.get(key).writeLock();
    readLock.lock();
    assertFalse(writeLock.tryLock());
    readLock.unlock();
  }

  @AndroidIncompatible // Presumably GC doesn't trigger, despite our efforts.
  public void testStrongImplementations() {

    Lock readLock = striped.get(key).readLock();
    WeakReference<Object> garbage = new WeakReference<>(new Object());
    GcFinalization.awaitClear(garbage);
    Lock writeLock = striped.get(key).writeLock();
    readLock.lock();
    assertFalse(writeLock.tryLock());
    readLock.unlock();
  }

  @AndroidIncompatible // Presumably GC doesn't trigger, despite our efforts.
  public void testStrongImplementations() {

    ) {
        for (registrar in registrars) {
            if (lock.readLock().withLock { application.isRegistrarRegistered(registrar) }) {
                continue
            }

            lock.writeLock().withLock {
                if (application.isRegistrarRegistered(registrar)) return@withLock
                registrar.register()
                application.serviceRegistered[registrar::class] = true
            }

func SendFile(dstFD *FD, src int, pos, remain int64) (written int64, err error, handled bool) {
	defer func() {
		TestHookDidSendFile(dstFD, src, written, err, handled)
	}()
	if err := dstFD.writeLock(); err != nil {
		return 0, err, false
	}
	defer dstFD.writeUnlock()

	if err := dstFD.pd.prepareWrite(dstFD.isFile); err != nil {
		return 0, err, false
	}

	dst := dstFD.Sysfd
	for remain > 0 {

//go:build windows

package filelock

import (
	"internal/syscall/windows"
	"io/fs"
	"syscall"
)

type lockType uint32

const (
	readLock  lockType = 0
	writeLock lockType = windows.LOCKFILE_EXCLUSIVE_LOCK
)

const (
	reserved = 0
	allBytes = ^uint32(0)
)

func lock(f File, lt lockType) error {
	// Per https://golang.org/issue/19098, “Programs currently expect the Fd

            // we only allow 1 promotion job running at the same time to avoid website xml conflicts
            feature {
                type = "JetBrains.SharedResources"
                param("locks-param", "WebsiteReleasesXml writeLock")
            }
        }
    }

      this.writeLock = new CycleDetectingReentrantWriteLock(this);
      this.lockGraphNode = Preconditions.checkNotNull(lockGraphNode);
    }

    ///// Overridden ReentrantReadWriteLock methods. /////

    @Override
    public ReadLock readLock() {
      return readLock;
    }

    @Override
    public WriteLock writeLock() {
      return writeLock;
    }

func SendFile(dstFD *FD, src int, pos, remain int64) (written int64, err error, handled bool) {
	defer func() {
		TestHookDidSendFile(dstFD, src, written, err, handled)
	}()
	if err := dstFD.writeLock(); err != nil {
		return 0, err, false
	}
	defer dstFD.writeUnlock()

	if err := dstFD.pd.prepareWrite(dstFD.isFile); err != nil {
		return 0, err, false
	}

	dst := dstFD.Sysfd
	for remain > 0 {

//go:build unix

package poll

import (
	"io"
	"runtime"
	"syscall"
)

// Writev wraps the writev system call.
func (fd *FD) Writev(v *[][]byte) (int64, error) {
	if err := fd.writeLock(); err != nil {
		return 0, err
	}
	defer fd.writeUnlock()
	if err := fd.pd.prepareWrite(fd.isFile); err != nil {
		return 0, err
	}

	var iovecs []syscall.Iovec
	if fd.iovecs != nil {