import okhttp3.internal.http2.Http2Stream
import okhttp3.internal.http2.Http2Writer

/**
 * Centralisation of central locks according to docs/contribute/concurrency.md
 */
internal object Locks {
  inline fun <T> Dispatcher.withLock(action: () -> T): T {
    contract { callsInPlace(action, InvocationKind.EXACTLY_ONCE) }
    return lock.withLock(action)
  }

  inline fun <T> RealConnection.withLock(action: () -> T): T {

) : Http2Connection.Listener(), Connection, ExchangeCodec.Carrier {
  private var http2Connection: Http2Connection? = null

  internal val lock: ReentrantLock = ReentrantLock()

  // These properties are guarded by [lock].

  /**
   * If true, no new exchanges can be created on this connection. It is necessary to set this to

   * additional context. Otherwise [e] is returned as-is.
   */
  private fun <E : IOException?> callDone(e: E): E {
    lock.assertNotHeld()

    val connection = this.connection
    if (connection != null) {
      connection.lock.assertNotHeld()
      val toClose: Socket? =
        connection.withLock {
          // Sets this.connection to null.
          releaseConnectionNoEvents()

### 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

import java.net.SocketTimeoutException
import java.util.ArrayDeque
import java.util.concurrent.locks.Condition
import java.util.concurrent.locks.ReentrantLock
import okhttp3.Headers
import okhttp3.internal.EMPTY_HEADERS
import okhttp3.internal.assertNotHeld
import okhttp3.internal.connection.Locks.withLock
import okhttp3.internal.http2.flowcontrol.WindowCounter
import okhttp3.internal.toHeaderList

import java.util.concurrent.SynchronousQueue
import java.util.concurrent.ThreadFactory
import java.util.concurrent.ThreadPoolExecutor
import java.util.concurrent.TimeUnit
import java.util.concurrent.locks.Condition
import java.util.concurrent.locks.ReentrantLock
import java.util.logging.Logger
import kotlin.concurrent.withLock
import okhttp3.internal.addIfAbsent
import okhttp3.internal.assertHeld

 * limitations under the License.
 */
package okhttp3.internal.http2

import java.io.Closeable
import java.io.IOException
import java.util.concurrent.locks.ReentrantLock
import java.util.logging.Level.FINE
import java.util.logging.Logger
import okhttp3.internal.connection.Locks.withLock
import okhttp3.internal.format
import okhttp3.internal.http2.Http2.CONNECTION_PREFACE
import okhttp3.internal.http2.Http2.FLAG_ACK

import java.util.concurrent.SynchronousQueue
import java.util.concurrent.ThreadPoolExecutor
import java.util.concurrent.TimeUnit
import java.util.concurrent.locks.ReentrantLock
import okhttp3.internal.assertNotHeld
import okhttp3.internal.connection.Locks.withLock
import okhttp3.internal.connection.RealCall
import okhttp3.internal.connection.RealCall.AsyncCall
import okhttp3.internal.okHttpName
import okhttp3.internal.threadFactory

   * be removed from the execution schedule.
   */
  fun cancelAll() {
    lock.assertNotHeld()

    taskRunner.lock.withLock {
      if (cancelAllAndDecide()) {
        taskRunner.kickCoordinator(this)
      }
    }
  }

  fun shutdown() {
    lock.assertNotHeld()

    taskRunner.lock.withLock {
      shutdown = true
      if (cancelAllAndDecide()) {

import okhttp3.internal.concurrent.TaskRunner
import okhttp3.internal.connection.CallConnectionUser
import okhttp3.internal.connection.FastFallbackExchangeFinder
import okhttp3.internal.connection.Locks.withLock
import okhttp3.internal.connection.RealCall
import okhttp3.internal.connection.RealConnection
import okhttp3.internal.connection.RealConnectionPool
import okhttp3.internal.connection.RealRoutePlanner