/** Encode requests and responses using HTTP/2 frames. */
class Http2ExchangeCodec(
  client: OkHttpClient,
  override val carrier: Carrier,
  private val chain: RealInterceptorChain,
  private val http2Connection: Http2Connection,
) : ExchangeCodec {
  @Volatile private var stream: Http2Stream? = null

  private val protocol: Protocol =
    if (Protocol.H2_PRIOR_KNOWLEDGE in client.protocols) {
      Protocol.H2_PRIOR_KNOWLEDGE

import okhttp3.Protocol
import okhttp3.Protocol.Companion.get
import okhttp3.internal.closeQuietly
import okhttp3.internal.concurrent.TaskRunner
import okhttp3.internal.http2.Header
import okhttp3.internal.http2.Http2Connection
import okhttp3.internal.http2.Http2Stream
import okhttp3.internal.platform.Platform
import okhttp3.tls.internal.TlsUtil.localhost
import okio.buffer
import okio.source

import kotlin.concurrent.withLock
import kotlin.contracts.ExperimentalContracts
import kotlin.contracts.InvocationKind
import kotlin.contracts.contract
import okhttp3.Dispatcher
import okhttp3.internal.http2.Http2Connection
import okhttp3.internal.http2.Http2Stream
import okhttp3.internal.http2.Http2Writer

/**
 * Centralisation of central locks according to docs/contribute/concurrency.md
 */
internal object Locks {

### 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.

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

/**
 * Settings describe characteristics of the sending peer, which are used by the receiving peer.
 * Settings are [connection][Http2Connection] scoped.
 */
class Settings {
  /** Bitfield of which flags that values. */
  private var set: Int = 0

  /** Flag values. */
  private val values = IntArray(COUNT)

  /** Returns -1 if unset. */