pythonnet/src/runtime/typemanager.cs at master · captainfunk/pythonnet · GitHub

Repository navigation

History

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

727

728

729

730

731

732

733

734

735

736

737

738

739

740

741

742

743

744

745

746

747

748

749

750

751

752

753

754

755

756

757

758

759

760

761

762

763

764

765

766

767

768

769

770

771

772

773

774

775

776

777

778

779

780

781

782

783

784

785

786

787

788

789

790

791

792

793

794

using System;

using System.Collections;

using System.Collections.Generic;

using System.Reflection;

using System.Runtime.InteropServices;

namespace Python.Runtime

{

/// <summary>

/// The TypeManager class is responsible for building binary-compatible

/// Python type objects that are implemented in managed code.

/// </summary>

internal class TypeManager

{

private static BindingFlags tbFlags;

private static Dictionary<Type, IntPtr> cache;

static TypeManager()

{

tbFlags = BindingFlags.Public | BindingFlags.Static;

cache = new Dictionary<Type, IntPtr>(128);

}

public static void Reset()

{

cache = new Dictionary<Type, IntPtr>(128);

}

/// <summary>

/// Given a managed Type derived from ExtensionType, get the handle to

/// a Python type object that delegates its implementation to the Type

/// object. These Python type instances are used to implement internal

/// descriptor and utility types like ModuleObject, PropertyObject, etc.

/// </summary>

internal static IntPtr GetTypeHandle(Type type)

{

// Note that these types are cached with a refcount of 1, so they

// effectively exist until the CPython runtime is finalized.

IntPtr handle;

cache.TryGetValue(type, out handle);

if (handle != IntPtr.Zero)

{

return handle;

}

handle = CreateType(type);

cache[type] = handle;

return handle;

}

/// <summary>

/// Get the handle of a Python type that reflects the given CLR type.

/// The given ManagedType instance is a managed object that implements

/// the appropriate semantics in Python for the reflected managed type.

/// </summary>

internal static IntPtr GetTypeHandle(ManagedType obj, Type type)

{

IntPtr handle;

cache.TryGetValue(type, out handle);

if (handle != IntPtr.Zero)

{

return handle;

}

handle = CreateType(obj, type);

cache[type] = handle;

return handle;

}

/// <summary>

/// The following CreateType implementations do the necessary work to

/// create Python types to represent managed extension types, reflected

/// types, subclasses of reflected types and the managed metatype. The

/// dance is slightly different for each kind of type due to different

/// behavior needed and the desire to have the existing Python runtime

/// do as much of the allocation and initialization work as possible.

/// </summary>

internal static IntPtr CreateType(Type impl)

{

IntPtr type = AllocateTypeObject(impl.Name);

int ob_size = ObjectOffset.Size(type);

// Set tp_basicsize to the size of our managed instance objects.

Marshal.WriteIntPtr(type, TypeOffset.tp_basicsize, (IntPtr)ob_size);

var offset = (IntPtr)ObjectOffset.DictOffset(type);

Marshal.WriteIntPtr(type, TypeOffset.tp_dictoffset, offset);

InitializeSlots(type, impl);

int flags = TypeFlags.Default | TypeFlags.Managed |

TypeFlags.HeapType | TypeFlags.HaveGC;

Util.WriteCLong(type, TypeOffset.tp_flags, flags);

Runtime.PyType_Ready(type);

IntPtr dict = Marshal.ReadIntPtr(type, TypeOffset.tp_dict);

IntPtr mod = Runtime.PyString_FromString("CLR");

Runtime.PyDict_SetItemString(dict, "__module__", mod);

InitMethods(type, impl);

return type;

}

internal static IntPtr CreateType(ManagedType impl, Type clrType)

{

// Cleanup the type name to get rid of funny nested type names.

string name = "CLR." + clrType.FullName;

int i = name.LastIndexOf('+');

if (i > -1)

{

name = name.Substring(i + 1);

}

i = name.LastIndexOf('.');

if (i > -1)

{

name = name.Substring(i + 1);

}

IntPtr base_ = IntPtr.Zero;

int ob_size = ObjectOffset.Size(Runtime.PyTypeType);

int tp_dictoffset = ObjectOffset.DictOffset(Runtime.PyTypeType);

// XXX Hack, use a different base class for System.Exception

// Python 2.5+ allows new style class exceptions but they *must*

// subclass BaseException (or better Exception).

if (typeof(Exception).IsAssignableFrom(clrType))

{

ob_size = ObjectOffset.Size(Exceptions.Exception);

tp_dictoffset = ObjectOffset.DictOffset(Exceptions.Exception);

}

if (clrType == typeof(Exception))

{

base_ = Exceptions.Exception;

}

else if (clrType.BaseType != null)

{

ClassBase bc = ClassManager.GetClass(clrType.BaseType);

base_ = bc.pyHandle;

}

IntPtr type = AllocateTypeObject(name);

Marshal.WriteIntPtr(type, TypeOffset.ob_type, Runtime.PyCLRMetaType);

Runtime.XIncref(Runtime.PyCLRMetaType);

Marshal.WriteIntPtr(type, TypeOffset.tp_basicsize, (IntPtr)ob_size);

Marshal.WriteIntPtr(type, TypeOffset.tp_itemsize, IntPtr.Zero);

Marshal.WriteIntPtr(type, TypeOffset.tp_dictoffset, (IntPtr)tp_dictoffset);

InitializeSlots(type, impl.GetType());

if (base_ != IntPtr.Zero)

{

Marshal.WriteIntPtr(type, TypeOffset.tp_base, base_);

Runtime.XIncref(base_);

}

int flags = TypeFlags.Default;

flags |= TypeFlags.Managed;

flags |= TypeFlags.HeapType;

flags |= TypeFlags.BaseType;

flags |= TypeFlags.HaveGC;

Util.WriteCLong(type, TypeOffset.tp_flags, flags);

// Leverage followup initialization from the Python runtime. Note

// that the type of the new type must PyType_Type at the time we

// call this, else PyType_Ready will skip some slot initialization.

Runtime.PyType_Ready(type);

IntPtr dict = Marshal.ReadIntPtr(type, TypeOffset.tp_dict);

string mn = clrType.Namespace ?? "";

IntPtr mod = Runtime.PyString_FromString(mn);

Runtime.PyDict_SetItemString(dict, "__module__", mod);

// Hide the gchandle of the implementation in a magic type slot.

GCHandle gc = GCHandle.Alloc(impl);

Marshal.WriteIntPtr(type, TypeOffset.magic(), (IntPtr)gc);

// Set the handle attributes on the implementing instance.

impl.tpHandle = Runtime.PyCLRMetaType;

impl.gcHandle = gc;

impl.pyHandle = type;

//DebugUtil.DumpType(type);

return type;

}

internal static IntPtr CreateSubType(IntPtr py_name, IntPtr py_base_type, IntPtr py_dict)

{

// Utility to create a subtype of a managed type with the ability for the

// a python subtype able to override the managed implementation

string name = Runtime.GetManagedString(py_name);

// the derived class can have class attributes __assembly__ and __module__ which

// control the name of the assembly and module the new type is created in.

object assembly = null;

object namespaceStr = null;

var disposeList = new List<PyObject>();

try

{

var assemblyKey = new PyObject(Converter.ToPython("__assembly__", typeof(string)));

disposeList.Add(assemblyKey);

if (0 != Runtime.PyMapping_HasKey(py_dict, assemblyKey.Handle))

{

var pyAssembly = new PyObject(Runtime.PyDict_GetItem(py_dict, assemblyKey.Handle));

Runtime.XIncref(pyAssembly.Handle);

disposeList.Add(pyAssembly);

if (!Converter.ToManagedValue(pyAssembly.Handle, typeof(string), out assembly, false))

{

throw new InvalidCastException("Couldn't convert __assembly__ value to string");

}

var namespaceKey = new PyObject(Converter.ToPythonImplicit("__namespace__"));

disposeList.Add(namespaceKey);

if (0 != Runtime.PyMapping_HasKey(py_dict, namespaceKey.Handle))

{

var pyNamespace = new PyObject(Runtime.PyDict_GetItem(py_dict, namespaceKey.Handle));

Runtime.XIncref(pyNamespace.Handle);

disposeList.Add(pyNamespace);

if (!Converter.ToManagedValue(pyNamespace.Handle, typeof(string), out namespaceStr, false))

{

throw new InvalidCastException("Couldn't convert __namespace__ value to string");

}

finally

{

foreach (PyObject o in disposeList)

{

o.Dispose();

}

// create the new managed type subclassing the base managed type

var baseClass = ManagedType.GetManagedObject(py_base_type) as ClassBase;

if (null == baseClass)

{

return Exceptions.RaiseTypeError("invalid base class, expected CLR class type");

}

try

{

Type subType = ClassDerivedObject.CreateDerivedType(name,

baseClass.type,

py_dict,

(string)namespaceStr,

(string)assembly);

// create the new ManagedType and python type

ClassBase subClass = ClassManager.GetClass(subType);

IntPtr py_type = GetTypeHandle(subClass, subType);

// by default the class dict will have all the C# methods in it, but as this is a

// derived class we want the python overrides in there instead if they exist.

IntPtr cls_dict = Marshal.ReadIntPtr(py_type, TypeOffset.tp_dict);

Runtime.PyDict_Update(cls_dict, py_dict);

return py_type;

}

catch (Exception e)

{

return Exceptions.RaiseTypeError(e.Message);

}

internal static IntPtr WriteMethodDef(IntPtr mdef, IntPtr name, IntPtr func, int flags, IntPtr doc)

{

Marshal.WriteIntPtr(mdef, name);

Marshal.WriteIntPtr(mdef, 1 * IntPtr.Size, func);

Marshal.WriteInt32(mdef, 2 * IntPtr.Size, flags);

Marshal.WriteIntPtr(mdef, 3 * IntPtr.Size, doc);

return mdef + 4 * IntPtr.Size;

}

internal static IntPtr WriteMethodDef(IntPtr mdef, string name, IntPtr func, int flags = 0x0001,

string doc = null)

{

IntPtr namePtr = Marshal.StringToHGlobalAnsi(name);

IntPtr docPtr = doc != null ? Marshal.StringToHGlobalAnsi(doc) : IntPtr.Zero;

return WriteMethodDef(mdef, namePtr, func, flags, docPtr);

}

internal static IntPtr WriteMethodDefSentinel(IntPtr mdef)

{

return WriteMethodDef(mdef, IntPtr.Zero, IntPtr.Zero, 0, IntPtr.Zero);

}

internal static IntPtr CreateMetaType(Type impl)

{

// The managed metatype is functionally little different than the

// standard Python metatype (PyType_Type). It overrides certain of

// the standard type slots, and has to subclass PyType_Type for

// certain functions in the C runtime to work correctly with it.

IntPtr type = AllocateTypeObject("CLR Metatype");

IntPtr py_type = Runtime.PyTypeType;

Marshal.WriteIntPtr(type, TypeOffset.tp_base, py_type);

Runtime.XIncref(py_type);

// Copy gc and other type slots from the base Python metatype.

CopySlot(py_type, type, TypeOffset.tp_basicsize);

CopySlot(py_type, type, TypeOffset.tp_itemsize);

CopySlot(py_type, type, TypeOffset.tp_dictoffset);

CopySlot(py_type, type, TypeOffset.tp_weaklistoffset);

CopySlot(py_type, type, TypeOffset.tp_traverse);

CopySlot(py_type, type, TypeOffset.tp_clear);

CopySlot(py_type, type, TypeOffset.tp_is_gc);

// Override type slots with those of the managed implementation.

InitializeSlots(type, impl);

int flags = TypeFlags.Default;

flags |= TypeFlags.Managed;

flags |= TypeFlags.HeapType;

flags |= TypeFlags.HaveGC;

Util.WriteCLong(type, TypeOffset.tp_flags, flags);

// We need space for 3 PyMethodDef structs, each of them

// 4 int-ptrs in size.

IntPtr mdef = Runtime.PyMem_Malloc(3 * 4 * IntPtr.Size);

IntPtr mdefStart = mdef;

mdef = WriteMethodDef(

mdef,

"__instancecheck__",

Interop.GetThunk(typeof(MetaType).GetMethod("__instancecheck__"), "BinaryFunc")

);

mdef = WriteMethodDef(

mdef,

"__subclasscheck__",

Interop.GetThunk(typeof(MetaType).GetMethod("__subclasscheck__"), "BinaryFunc")

);

// FIXME: mdef is not used

mdef = WriteMethodDefSentinel(mdef);

Marshal.WriteIntPtr(type, TypeOffset.tp_methods, mdefStart);

Runtime.PyType_Ready(type);

IntPtr dict = Marshal.ReadIntPtr(type, TypeOffset.tp_dict);

IntPtr mod = Runtime.PyString_FromString("CLR");

Runtime.PyDict_SetItemString(dict, "__module__", mod);

//DebugUtil.DumpType(type);

return type;

}

internal static IntPtr BasicSubType(string name, IntPtr base_, Type impl)

{

// Utility to create a subtype of a std Python type, but with

// a managed type able to override implementation

IntPtr type = AllocateTypeObject(name);

//Marshal.WriteIntPtr(type, TypeOffset.tp_basicsize, (IntPtr)obSize);

//Marshal.WriteIntPtr(type, TypeOffset.tp_itemsize, IntPtr.Zero);

//IntPtr offset = (IntPtr)ObjectOffset.ob_dict;

//Marshal.WriteIntPtr(type, TypeOffset.tp_dictoffset, offset);

//IntPtr dc = Runtime.PyDict_Copy(dict);

//Marshal.WriteIntPtr(type, TypeOffset.tp_dict, dc);

Marshal.WriteIntPtr(type, TypeOffset.tp_base, base_);

Runtime.XIncref(base_);

int flags = TypeFlags.Default;

flags |= TypeFlags.Managed;

flags |= TypeFlags.HeapType;

flags |= TypeFlags.HaveGC;

Util.WriteCLong(type, TypeOffset.tp_flags, flags);

CopySlot(base_, type, TypeOffset.tp_traverse);

CopySlot(base_, type, TypeOffset.tp_clear);

CopySlot(base_, type, TypeOffset.tp_is_gc);

InitializeSlots(type, impl);

Runtime.PyType_Ready(type);

IntPtr tp_dict = Marshal.ReadIntPtr(type, TypeOffset.tp_dict);

IntPtr mod = Runtime.PyString_FromString("CLR");

Runtime.PyDict_SetItemString(tp_dict, "__module__", mod);

return type;

}

/// <summary>

/// Utility method to allocate a type object & do basic initialization.

/// </summary>

internal static IntPtr AllocateTypeObject(string name)

{

IntPtr type = Runtime.PyType_GenericAlloc(Runtime.PyTypeType, 0);

// Cheat a little: we'll set tp_name to the internal char * of

// the Python version of the type name - otherwise we'd have to

// allocate the tp_name and would have no way to free it.

#if PYTHON3

// For python3 we leak two objects. One for the ASCII representation

// required for tp_name, and another for the Unicode representation

// for ht_name.

IntPtr temp = Runtime.PyBytes_FromString(name);

IntPtr raw = Runtime.PyBytes_AS_STRING(temp);

temp = Runtime.PyUnicode_FromString(name);

#elif PYTHON2

IntPtr temp = Runtime.PyString_FromString(name);

IntPtr raw = Runtime.PyString_AsString(temp);

#endif

Marshal.WriteIntPtr(type, TypeOffset.tp_name, raw);

Marshal.WriteIntPtr(type, TypeOffset.name, temp);

#if PYTHON3

Marshal.WriteIntPtr(type, TypeOffset.qualname, temp);

#endif

long ptr = type.ToInt64(); // 64-bit safe

temp = new IntPtr(ptr + TypeOffset.nb_add);

Marshal.WriteIntPtr(type, TypeOffset.tp_as_number, temp);

temp = new IntPtr(ptr + TypeOffset.sq_length);

Marshal.WriteIntPtr(type, TypeOffset.tp_as_sequence, temp);

temp = new IntPtr(ptr + TypeOffset.mp_length);

Marshal.WriteIntPtr(type, TypeOffset.tp_as_mapping, temp);

#if PYTHON3

temp = new IntPtr(ptr + TypeOffset.bf_getbuffer);

#elif PYTHON2

temp = new IntPtr(ptr + TypeOffset.bf_getreadbuffer);

#endif

Marshal.WriteIntPtr(type, TypeOffset.tp_as_buffer, temp);

return type;

}

#region Native Code Page

/// <summary>

/// Initialized by InitializeNativeCodePage.

///

/// This points to a page of memory allocated using mmap or VirtualAlloc

/// (depending on the system), and marked read and execute (not write).

/// Very much on purpose, the page is *not* released on a shutdown and

/// is instead leaked. See the TestDomainReload test case.

///

/// The contents of the page are two native functions: one that returns 0,

/// one that returns 1.

///

/// If python didn't keep its gc list through a Py_Finalize we could remove

/// this entire section.

/// </summary>

internal static IntPtr NativeCodePage = IntPtr.Zero;

/// <summary>

/// Structure to describe native code.

///

/// Use NativeCode.Active to get the native code for the current platform.

///

/// Generate the code by creating the following C code:

/// <code>

/// int Return0() { return 0; }

/// int Return1() { return 1; }

/// </code>

/// Then compiling on the target platform, e.g. with gcc or clang:

/// <code>cc -c -fomit-frame-pointer -O2 foo.c</code>

/// And then analyzing the resulting functions with a hex editor, e.g.:

/// <code>objdump -disassemble foo.o</code>

/// </summary>

internal class NativeCode

{

/// <summary>

/// The code, as a string of bytes.

/// </summary>

public byte[] Code { get; private set; }

/// <summary>

/// Where does the "return 0" function start?

/// </summary>

public int Return0 { get; private set; }

/// <summary>

/// Where does the "return 1" function start?

/// </summary>

public int Return1 { get; private set; }

public static NativeCode Active

{

get

{

switch(Runtime.Machine)

{

case Runtime.MachineType.i386:

return I386;

case Runtime.MachineType.x86_64:

return X86_64;

default:

throw new NotImplementedException($"No support for {Runtime.MachineName}");

}

/// <summary>

/// Code for x86_64. See the class comment for how it was generated.

/// </summary>

public static readonly NativeCode X86_64 = new NativeCode()

{

Return0 = 0x10,

Return1 = 0,

Code = new byte[]

{

// First Return1:

0xb8, 0x01, 0x00, 0x00, 0x00, // movl $1, %eax

0xc3, // ret

// Now some padding so that Return0 can be 16-byte-aligned.

// I put Return1 first so there's not as much padding to type in.

0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00, // nop

// Now Return0.

0x31, 0xc0, // xorl %eax, %eax

0xc3, // ret

}

};

/// <summary>

/// Code for X86.

///

/// It's bitwise identical to X86_64, so we just point to it.

/// <see cref="NativeCode.X86_64"/>

/// </summary>

public static readonly NativeCode I386 = X86_64;

}

/// <summary>

/// Platform-dependent mmap and mprotect.

/// </summary>

internal interface IMemoryMapper

{

/// <summary>

/// Map at least numBytes of memory. Mark the page read-write (but not exec).

/// </summary>

IntPtr MapWriteable(int numBytes);

/// <summary>

/// Sets the mapped memory to be read-exec (but not write).

/// </summary>

void SetReadExec(IntPtr mappedMemory, int numBytes);

}

class WindowsMemoryMapper : IMemoryMapper

{

const UInt32 MEM_COMMIT = 0x1000;

const UInt32 MEM_RESERVE = 0x2000;

const UInt32 PAGE_READWRITE = 0x04;

const UInt32 PAGE_EXECUTE_READ = 0x20;

[DllImport("kernel32.dll")]

static extern IntPtr VirtualAlloc(IntPtr lpAddress, IntPtr dwSize, UInt32 flAllocationType, UInt32 flProtect);

[DllImport("kernel32.dll")]

static extern bool VirtualProtect(IntPtr lpAddress, IntPtr dwSize, UInt32 flNewProtect, out UInt32 lpflOldProtect);

public IntPtr MapWriteable(int numBytes)

{

return VirtualAlloc(IntPtr.Zero, new IntPtr(numBytes),

MEM_RESERVE | MEM_COMMIT, PAGE_READWRITE);

}

public void SetReadExec(IntPtr mappedMemory, int numBytes)

{

UInt32 _;

VirtualProtect(mappedMemory, new IntPtr(numBytes), PAGE_EXECUTE_READ, out _);

}

class UnixMemoryMapper : IMemoryMapper

{

const int PROT_READ = 0x1;

const int PROT_WRITE = 0x2;

const int PROT_EXEC = 0x4;

const int MAP_PRIVATE = 0x2;

int MAP_ANONYMOUS

{

get

{

switch (Runtime.OperatingSystem)

{

case Runtime.OperatingSystemType.Darwin:

return 0x1000;

case Runtime.OperatingSystemType.Linux:

return 0x20;

default:

throw new NotImplementedException($"mmap is not supported on {Runtime.OperatingSystemName}");

}

[DllImport("libc")]

static extern IntPtr mmap(IntPtr addr, IntPtr len, int prot, int flags, int fd, IntPtr offset);

[DllImport("libc")]

static extern int mprotect(IntPtr addr, IntPtr len, int prot);

public IntPtr MapWriteable(int numBytes)

{

// MAP_PRIVATE must be set on linux, even though MAP_ANON implies it.

// It doesn't hurt on darwin, so just do it.

return mmap(IntPtr.Zero, new IntPtr(numBytes), PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, IntPtr.Zero);

}

public void SetReadExec(IntPtr mappedMemory, int numBytes)

{

mprotect(mappedMemory, new IntPtr(numBytes), PROT_READ | PROT_EXEC);

}

internal static IMemoryMapper CreateMemoryMapper()

{

switch (Runtime.OperatingSystem)

{

case Runtime.OperatingSystemType.Darwin:

case Runtime.OperatingSystemType.Linux:

return new UnixMemoryMapper();

case Runtime.OperatingSystemType.Windows:

return new WindowsMemoryMapper();

default:

throw new NotImplementedException($"No support for {Runtime.OperatingSystemName}");

}

/// <summary>

/// Initializes the native code page.

///

/// Safe to call if we already initialized (this function is idempotent).

/// <see cref="NativeCodePage"/>

/// </summary>

internal static void InitializeNativeCodePage()

{

// Do nothing if we already initialized.

if (NativeCodePage != IntPtr.Zero)

{

return;

}

// Allocate the page, write the native code into it, then set it

// to be executable.

IMemoryMapper mapper = CreateMemoryMapper();

int codeLength = NativeCode.Active.Code.Length;

NativeCodePage = mapper.MapWriteable(codeLength);

Marshal.Copy(NativeCode.Active.Code, 0, NativeCodePage, codeLength);

mapper.SetReadExec(NativeCodePage, codeLength);

}

#endregion

/// <summary>

/// Given a newly allocated Python type object and a managed Type that

/// provides the implementation for the type, connect the type slots of

/// the Python object to the managed methods of the implementing Type.

/// </summary>

internal static void InitializeSlots(IntPtr type, Type impl)

{

// We work from the most-derived class up; make sure to get

// the most-derived slot and not to override it with a base

// class's slot.

var seen = new HashSet<string>();

while (impl != null)

{

MethodInfo[] methods = impl.GetMethods(tbFlags);

foreach (MethodInfo method in methods)

{

string name = method.Name;

if (!(name.StartsWith("tp_") ||

name.StartsWith("nb_") ||

name.StartsWith("sq_") ||

name.StartsWith("mp_") ||

name.StartsWith("bf_")

))

{

continue;

}

if (seen.Contains(name))

{

continue;

}

InitializeSlot(type, Interop.GetThunk(method), name);

seen.Add(name);

}

impl = impl.BaseType;

}

// See the TestDomainReload test: there was a crash related to

// the gc-related slots. They always return 0 or 1 because we don't

// really support gc:

// tp_traverse (returns 0)

// tp_clear (returns 0)

// tp_is_gc (returns 1)

// We can't do without: python really wants those slots to exist.

// We can't implement those in C# because the application domain

// can be shut down and the memory released.

InitializeNativeCodePage();

InitializeSlot(type, NativeCodePage + NativeCode.Active.Return0, "tp_traverse");

InitializeSlot(type, NativeCodePage + NativeCode.Active.Return0, "tp_clear");

InitializeSlot(type, NativeCodePage + NativeCode.Active.Return1, "tp_is_gc");

}

/// <summary>

/// Helper for InitializeSlots.

///

/// Initializes one slot to point to a function pointer.

/// The function pointer might be a thunk for C#, or it may be

/// an address in the NativeCodePage.

/// </summary>

/// <param name="type">Type being initialized.</param>

/// <param name="slot">Function pointer.</param>

/// <param name="name">Name of the method.</param>

static void InitializeSlot(IntPtr type, IntPtr slot, string name)

{

Type typeOffset = typeof(TypeOffset);

FieldInfo fi = typeOffset.GetField(name);

var offset = (int)fi.GetValue(typeOffset);

Marshal.WriteIntPtr(type, offset, slot);

}

/// <summary>

/// Given a newly allocated Python type object and a managed Type that

/// implements it, initialize any methods defined by the Type that need

/// to appear in the Python type __dict__ (based on custom attribute).

/// </summary>

private static void InitMethods(IntPtr pytype, Type type)

{

IntPtr dict = Marshal.ReadIntPtr(pytype, TypeOffset.tp_dict);

Type marker = typeof(PythonMethodAttribute);

BindingFlags flags = BindingFlags.Public | BindingFlags.Static;

var addedMethods = new HashSet<string>();

while (type != null)

{

MethodInfo[] methods = type.GetMethods(flags);

foreach (MethodInfo method in methods)

{

if (!addedMethods.Contains(method.Name))

{

object[] attrs = method.GetCustomAttributes(marker, false);

if (attrs.Length > 0)

{

string method_name = method.Name;

var mi = new MethodInfo[1];

mi[0] = method;

MethodObject m = new TypeMethod(type, method_name, mi);

Runtime.PyDict_SetItemString(dict, method_name, m.pyHandle);

addedMethods.Add(method_name);

}

type = type.BaseType;

}

/// <summary>

/// Utility method to copy slots from a given type to another type.

/// </summary>

internal static void CopySlot(IntPtr from, IntPtr to, int offset)

{

IntPtr fp = Marshal.ReadIntPtr(from, offset);

Marshal.WriteIntPtr(to, offset, fp);

}

pythonnet/src/runtime/typemanager.cs at master · captainfunk/pythonnet · GitHub

Repository navigation

Expand file tree

Breadcrumbs

typemanager.cs

Latest commit

History

Breadcrumbs

typemanager.cs

File metadata and controls