NetCoreServer/source/NetCoreServer/TcpSession.cs at master · StudyWithJeffrey/NetCoreServer · GitHub

Repository navigation

History

726 lines (604 loc) · 23 KB

Raw

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

179

180

181

182

183

184

185

186

187

188

189

190

191

192

193

194

195

196

197

198

199

200

201

202

203

204

205

206

207

208

209

210

211

212

213

214

215

216

217

218

219

220

221

222

223

224

225

226

227

228

229

230

231

232

233

234

235

236

237

238

239

240

241

242

243

244

245

246

247

248

249

250

251

252

253

254

255

256

257

258

259

260

261

262

263

264

265

266

267

268

269

270

271

272

273

274

275

276

277

278

279

280

281

282

283

284

285

286

287

288

289

290

291

292

293

294

295

296

297

298

299

300

301

302

303

304

305

306

307

308

309

310

311

312

313

314

315

316

317

318

319

320

321

322

323

324

325

326

327

328

329

330

331

332

333

334

335

336

337

338

339

340

341

342

343

344

345

346

347

348

349

350

351

352

353

354

355

356

357

358

359

360

361

362

363

364

365

366

367

368

369

370

371

372

373

374

375

376

377

378

379

380

381

382

383

384

385

386

387

388

389

390

391

392

393

394

395

396

397

398

399

400

401

402

403

404

405

406

407

408

409

410

411

412

413

414

415

416

417

418

419

420

421

422

423

424

425

426

427

428

429

430

431

432

433

434

435

436

437

438

439

440

441

442

443

444

445

446

447

448

449

450

451

452

453

454

455

456

457

458

459

460

461

462

463

464

465

466

467

468

469

470

471

472

473

474

475

476

477

478

479

480

481

482

483

484

485

486

487

488

489

490

491

492

493

494

495

496

497

498

499

500

501

502

503

504

505

506

507

508

509

510

511

512

513

514

515

516

517

518

519

520

521

522

523

524

525

526

527

528

529

530

531

532

533

534

535

536

537

538

539

540

541

542

543

544

545

546

547

548

549

550

551

552

553

554

555

556

557

558

559

560

561

562

563

564

565

566

567

568

569

570

571

572

573

574

575

576

577

578

579

580

581

582

583

584

585

586

587

588

589

590

591

592

593

594

595

596

597

598

599

600

601

602

603

604

605

606

607

608

609

610

611

612

613

614

615

616

617

618

619

620

621

622

623

624

625

626

627

628

629

630

631

632

633

634

635

636

637

638

639

640

641

642

643

644

645

646

647

648

649

650

651

652

653

654

655

656

657

658

659

660

661

662

663

664

665

666

667

668

669

670

671

672

673

674

675

676

677

678

679

680

681

682

683

684

685

686

687

688

689

690

691

692

693

694

695

696

697

698

699

700

701

702

703

704

705

706

707

708

709

710

711

712

713

714

715

716

717

718

719

720

721

722

723

724

725

726

using System;

using System.Net.Sockets;

using System.Text;

using System.Threading;

using System.Threading.Tasks;

namespace NetCoreServer

{

/// <summary>

/// TCP session is used to read and write data from the connected TCP client

/// </summary>

/// <remarks>Thread-safe</remarks>

public class TcpSession : IDisposable

{

/// <summary>

/// Initialize the session with a given server

/// </summary>

/// <param name="server">TCP server</param>

public TcpSession(TcpServer server)

{

Id = Guid.NewGuid();

Server = server;

OptionReceiveBufferSize = server.OptionReceiveBufferSize;

OptionSendBufferSize = server.OptionSendBufferSize;

}

/// <summary>

/// Session Id

/// </summary>

public Guid Id { get; }

/// <summary>

/// Server

/// </summary>

public TcpServer Server { get; }

/// <summary>

/// Socket

/// </summary>

public Socket Socket { get; private set; }

/// <summary>

/// Number of bytes pending sent by the session

/// </summary>

public long BytesPending { get; private set; }

/// <summary>

/// Number of bytes sending by the session

/// </summary>

public long BytesSending { get; private set; }

/// <summary>

/// Number of bytes sent by the session

/// </summary>

public long BytesSent { get; private set; }

/// <summary>

/// Number of bytes received by the session

/// </summary>

public long BytesReceived { get; private set; }

/// <summary>

/// Option: receive buffer size

/// </summary>

public int OptionReceiveBufferSize { get; set; } = 8192;

/// <summary>

/// Option: send buffer size

/// </summary>

public int OptionSendBufferSize { get; set; } = 8192;

#region Connect/Disconnect session

/// <summary>

/// Is the session connected?

/// </summary>

public bool IsConnected { get; private set; }

/// <summary>

/// Connect the session

/// </summary>

/// <param name="socket">Session socket</param>

internal void Connect(Socket socket)

{

Socket = socket;

// Update the session socket disposed flag

IsSocketDisposed = false;

// Setup buffers

_receiveBuffer = new Buffer();

_sendBufferMain = new Buffer();

_sendBufferFlush = new Buffer();

// Setup event args

_receiveEventArg = new SocketAsyncEventArgs();

_receiveEventArg.Completed += OnAsyncCompleted;

_sendEventArg = new SocketAsyncEventArgs();

_sendEventArg.Completed += OnAsyncCompleted;

// Apply the option: keep alive

if (Server.OptionKeepAlive)

Socket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.KeepAlive, true);

// Apply the option: no delay

if (Server.OptionNoDelay)

Socket.SetSocketOption(SocketOptionLevel.Tcp, SocketOptionName.NoDelay, true);

// Prepare receive & send buffers

_receiveBuffer.Reserve(OptionReceiveBufferSize);

_sendBufferMain.Reserve(OptionSendBufferSize);

_sendBufferFlush.Reserve(OptionSendBufferSize);

// Reset statistic

BytesPending = 0;

BytesSending = 0;

BytesSent = 0;

BytesReceived = 0;

// Update the connected flag

IsConnected = true;

// Call the session connected handler

OnConnected();

// Call the session connected handler in the server

Server.OnConnectedInternal(this);

// Call the empty send buffer handler

if (_sendBufferMain.IsEmpty)

OnEmpty();

// Try to receive something from the client

TryReceive();

}

/// <summary>

/// Disconnect the session

/// </summary>

/// <returns>'true' if the section was successfully disconnected, 'false' if the section is already disconnected</returns>

public virtual bool Disconnect()

{

if (!IsConnected)

return false;

// Reset event args

_receiveEventArg.Completed -= OnAsyncCompleted;

_sendEventArg.Completed -= OnAsyncCompleted;

try

{

try

{

// Shutdown the socket associated with the client

Socket.Shutdown(SocketShutdown.Both);

}

catch (SocketException) {}

// Close the session socket

Socket.Close();

// Dispose the session socket

Socket.Dispose();

// Dispose event arguments

_receiveEventArg.Dispose();

_sendEventArg.Dispose();

// Update the session socket disposed flag

IsSocketDisposed = true;

}

catch (ObjectDisposedException) {}

// Update the connected flag

IsConnected = false;

// Update sending/receiving flags

_receiving = false;

_sending = false;

// Clear send/receive buffers

ClearBuffers();

// Call the session disconnected handler

OnDisconnected();

// Call the session disconnected handler in the server

Server.OnDisconnectedInternal(this);

// Unregister session

Server.UnregisterSession(Id);

return true;

}

#endregion

#region Send/Recieve data

// Receive buffer

private bool _receiving;

private Buffer _receiveBuffer;

private SocketAsyncEventArgs _receiveEventArg;

// Send buffer

private readonly object _sendLock = new object();

private bool _sending;

private Buffer _sendBufferMain;

private Buffer _sendBufferFlush;

private SocketAsyncEventArgs _sendEventArg;

private long _sendBufferFlushOffset;

/// <summary>

/// Send data to the client (synchronous)

/// </summary>

/// <param name="buffer">Buffer to send</param>

/// <returns>Size of sent data</returns>

public virtual long Send(byte[] buffer) { return Send(buffer, 0, buffer.Length); }

/// <summary>

/// Send data to the client (synchronous)

/// </summary>

/// <param name="buffer">Buffer to send</param>

/// <param name="offset">Buffer offset</param>

/// <param name="size">Buffer size</param>

/// <returns>Size of sent data</returns>

public virtual long Send(byte[] buffer, long offset, long size)

{

if (!IsConnected)

return 0;

if (size == 0)

return 0;

// Sent data to the client

long sent = Socket.Send(buffer, (int)offset, (int)size, SocketFlags.None, out SocketError ec);

if (sent > 0)

{

// Update statistic

BytesSent += sent;

Interlocked.Add(ref Server._bytesSent, size);

// Call the buffer sent handler

OnSent(sent, BytesPending + BytesSending);

}

// Check for socket error

if (ec != SocketError.Success)

{

SendError(ec);

Disconnect();

}

return sent;

}

/// <summary>

/// Send text to the client (synchronous)

/// </summary>

/// <param name="text">Text string to send</param>

/// <returns>Size of sent data</returns>

public virtual long Send(string text) { return Send(Encoding.UTF8.GetBytes(text)); }

/// <summary>

/// Send data to the client (asynchronous)

/// </summary>

/// <param name="buffer">Buffer to send</param>

/// <returns>'true' if the data was successfully sent, 'false' if the session is not connected</returns>

public virtual bool SendAsync(byte[] buffer) { return SendAsync(buffer, 0, buffer.Length); }

/// <summary>

/// Send data to the client (asynchronous)

/// </summary>

/// <param name="buffer">Buffer to send</param>

/// <param name="offset">Buffer offset</param>

/// <param name="size">Buffer size</param>

/// <returns>'true' if the data was successfully sent, 'false' if the session is not connected</returns>

public virtual bool SendAsync(byte[] buffer, long offset, long size)

{

if (!IsConnected)

return false;

if (size == 0)

return true;

lock (_sendLock)

{

// Detect multiple send handlers

bool sendRequired = _sendBufferMain.IsEmpty || _sendBufferFlush.IsEmpty;

// Fill the main send buffer

_sendBufferMain.Append(buffer, offset, size);

// Update statistic

BytesPending = _sendBufferMain.Size;

// Avoid multiple send handlers

if (!sendRequired)

return true;

}

// Try to send the main buffer

Task.Factory.StartNew(TrySend);

return true;

}

/// <summary>

/// Send text to the client (asynchronous)

/// </summary>

/// <param name="text">Text string to send</param>

/// <returns>'true' if the text was successfully sent, 'false' if the session is not connected</returns>

public virtual bool SendAsync(string text) { return SendAsync(Encoding.UTF8.GetBytes(text)); }

/// <summary>

/// Receive data from the client (synchronous)

/// </summary>

/// <param name="buffer">Buffer to receive</param>

/// <returns>Size of received data</returns>

public virtual long Receive(byte[] buffer) { return Receive(buffer, 0, buffer.Length); }

/// <summary>

/// Receive data from the client (synchronous)

/// </summary>

/// <param name="buffer">Buffer to receive</param>

/// <param name="offset">Buffer offset</param>

/// <param name="size">Buffer size</param>

/// <returns>Size of received data</returns>

public virtual long Receive(byte[] buffer, long offset, long size)

{

if (!IsConnected)

return 0;

if (size == 0)

return 0;

// Receive data from the client

long received = Socket.Receive(buffer, (int)offset, (int)size, SocketFlags.None, out SocketError ec);

if (received > 0)

{

// Update statistic

BytesReceived += received;

Interlocked.Add(ref Server._bytesReceived, received);

// Call the buffer received handler

OnReceived(buffer, 0, received);

}

// Check for socket error

if (ec != SocketError.Success)

{

SendError(ec);

Disconnect();

}

return received;

}

/// <summary>

/// Receive text from the client (synchronous)

/// </summary>

/// <param name="size">Text size to receive</param>

/// <returns>Received text</returns>

public virtual string Receive(long size)

{

var buffer = new byte[size];

var length = Receive(buffer);

return Encoding.UTF8.GetString(buffer, 0, (int)length);

}

/// <summary>

/// Receive data from the client (asynchronous)

/// </summary>

public virtual void ReceiveAsync()

{

// Try to receive data from the client

TryReceive();

}

/// <summary>

/// Try to receive new data

/// </summary>

private void TryReceive()

{

if (_receiving)

return;

if (!IsConnected)

return;

bool process = true;

while (process)

{

process = false;

try

{

// Async receive with the receive handler

_receiving = true;

_receiveEventArg.SetBuffer(_receiveBuffer.Data, 0, (int)_receiveBuffer.Capacity);

if (!Socket.ReceiveAsync(_receiveEventArg))

process = ProcessReceive(_receiveEventArg);

}

catch (ObjectDisposedException) {}

}

/// <summary>

/// Try to send pending data

/// </summary>

private void TrySend()

{

if (_sending)

return;

if (!IsConnected)

return;

bool process = true;

while (process)

{

process = false;

lock (_sendLock)

{

if (_sending)

return;

// Swap send buffers

if (_sendBufferFlush.IsEmpty)

{

// Swap flush and main buffers

_sendBufferFlush = Interlocked.Exchange(ref _sendBufferMain, _sendBufferFlush);

_sendBufferFlushOffset = 0;

// Update statistic

BytesPending = 0;

BytesSending += _sendBufferFlush.Size;

_sending = !_sendBufferFlush.IsEmpty;

}

else

return;

}

// Check if the flush buffer is empty

if (_sendBufferFlush.IsEmpty)

{

// Call the empty send buffer handler

OnEmpty();

return;

}

try

{

// Async write with the write handler

_sendEventArg.SetBuffer(_sendBufferFlush.Data, (int)_sendBufferFlushOffset, (int)(_sendBufferFlush.Size - _sendBufferFlushOffset));

if (!Socket.SendAsync(_sendEventArg))

process = ProcessSend(_sendEventArg);

}

catch (ObjectDisposedException) {}

}

/// <summary>

/// Clear send/receive buffers

/// </summary>

private void ClearBuffers()

{

lock (_sendLock)

{

// Clear send buffers

_sendBufferMain.Clear();

_sendBufferFlush.Clear();

_sendBufferFlushOffset= 0;

// Update statistic

BytesPending = 0;

BytesSending = 0;

}

#endregion

#region IO processing

/// <summary>

/// This method is called whenever a receive or send operation is completed on a socket

/// </summary>

private void OnAsyncCompleted(object sender, SocketAsyncEventArgs e)

{

// Determine which type of operation just completed and call the associated handler

switch (e.LastOperation)

{

case SocketAsyncOperation.Receive:

if (ProcessReceive(e))

TryReceive();

break;

case SocketAsyncOperation.Send:

if (ProcessSend(e))

TrySend();

break;

default:

throw new ArgumentException("The last operation completed on the socket was not a receive or send");

}

/// <summary>

/// This method is invoked when an asynchronous receive operation completes

/// </summary>

private bool ProcessReceive(SocketAsyncEventArgs e)

{

if (!IsConnected)

return false;

long size = e.BytesTransferred;

// Received some data from the client

if (size > 0)

{

// Update statistic

BytesReceived += size;

Interlocked.Add(ref Server._bytesReceived, size);

// Call the buffer received handler

OnReceived(_receiveBuffer.Data, 0, size);

// If the receive buffer is full increase its size

if (_receiveBuffer.Capacity == size)

_receiveBuffer.Reserve(2 * size);

}

_receiving = false;

// Try to receive again if the session is valid

if (e.SocketError == SocketError.Success)

{

// If zero is returned from a read operation, the remote end has closed the connection

if (size > 0)

return true;

else

Disconnect();

}

else

{

SendError(e.SocketError);

Disconnect();

}

return false;

}

/// <summary>

/// This method is invoked when an asynchronous send operation completes

/// </summary>

private bool ProcessSend(SocketAsyncEventArgs e)

{

if (!IsConnected)

return false;

long size = e.BytesTransferred;

// Send some data to the client

if (size > 0)

{

// Update statistic

BytesSending -= size;

BytesSent += size;

Interlocked.Add(ref Server._bytesSent, size);

// Increase the flush buffer offset

_sendBufferFlushOffset += size;

// Successfully send the whole flush buffer

if (_sendBufferFlushOffset == _sendBufferFlush.Size)

{

// Clear the flush buffer

_sendBufferFlush.Clear();

_sendBufferFlushOffset = 0;

}

// Call the buffer sent handler

OnSent(size, BytesPending + BytesSending);

}

_sending = false;

// Try to send again if the session is valid

if (e.SocketError == SocketError.Success)

return true;

else

{

SendError(e.SocketError);

Disconnect();

return false;

}

#endregion

#region Session handlers

/// <summary>

/// Handle client connected notification

/// </summary>

protected virtual void OnConnected() {}

/// <summary>

/// Handle client disconnected notification

/// </summary>

protected virtual void OnDisconnected() {}

/// <summary>

/// Handle buffer received notification

/// </summary>

/// <param name="buffer">Received buffer</param>

/// <param name="offset">Received buffer offset</param>

/// <param name="size">Received buffer size</param>

/// <remarks>

/// Notification is called when another chunk of buffer was received from the client

/// </remarks>

protected virtual void OnReceived(byte[] buffer, long offset, long size) {}

/// <summary>

/// Handle buffer sent notification

/// </summary>

/// <param name="sent">Size of sent buffer</param>

/// <param name="pending">Size of pending buffer</param>

/// <remarks>

/// Notification is called when another chunk of buffer was sent to the client.

/// This handler could be used to send another buffer to the client for instance when the pending size is zero.

/// </remarks>

protected virtual void OnSent(long sent, long pending) {}

/// <summary>

/// Handle empty send buffer notification

/// </summary>

/// <remarks>

/// Notification is called when the send buffer is empty and ready for a new data to send.

/// This handler could be used to send another buffer to the client.

/// </remarks>

protected virtual void OnEmpty() {}

/// <summary>

/// Handle error notification

/// </summary>

/// <param name="error">Socket error code</param>

protected virtual void OnError(SocketError error) {}

#endregion

#region Error handling

/// <summary>

/// Send error notification

/// </summary>

/// <param name="error">Socket error code</param>

private void SendError(SocketError error)

{

// Skip disconnect errors

if ((error == SocketError.ConnectionAborted) ||

(error == SocketError.ConnectionRefused) ||

(error == SocketError.ConnectionReset) ||

(error == SocketError.OperationAborted) ||

(error == SocketError.Shutdown))

return;

OnError(error);

}

#endregion

#region IDisposable implementation

/// <summary>

/// Disposed flag

/// </summary>

public bool IsDisposed { get; private set; }

/// <summary>

/// Session socket disposed flag

/// </summary>

public bool IsSocketDisposed { get; private set; } = true;

// Implement IDisposable.

public void Dispose()

{

Dispose(true);

GC.SuppressFinalize(this);

}

protected virtual void Dispose(bool disposingManagedResources)

{

// The idea here is that Dispose(Boolean) knows whether it is

// being called to do explicit cleanup (the Boolean is true)

// versus being called due to a garbage collection (the Boolean

// is false). This distinction is useful because, when being

// disposed explicitly, the Dispose(Boolean) method can safely

// execute code using reference type fields that refer to other

// objects knowing for sure that these other objects have not been

// finalized or disposed of yet. When the Boolean is false,

// the Dispose(Boolean) method should not execute code that

// refer to reference type fields because those objects may

// have already been finalized."

if (!IsDisposed)

{

if (disposingManagedResources)

{

// Dispose managed resources here...

Disconnect();

}

// Dispose unmanaged resources here...

// Set large fields to null here...

// Mark as disposed.

IsDisposed = true;

}

// Use C# destructor syntax for finalization code.

~TcpSession()

{

// Simply call Dispose(false).

Dispose(false);

}

#endregion

}

NetCoreServer/source/NetCoreServer/TcpSession.cs at master · StudyWithJeffrey/NetCoreServer · GitHub

Repository navigation

Expand file tree

Breadcrumbs

TcpSession.cs

Latest commit

History

Breadcrumbs

TcpSession.cs

File metadata and controls