cpython/Python/ceval.c at 3.11 · python/cpython · 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

795

796

797

798

799

800

801

802

803

804

805

806

807

808

809

810

811

812

813

814

815

816

817

818

819

820

821

822

823

824

825

826

827

828

829

830

831

832

833

834

835

836

837

838

839

840

841

842

843

844

845

846

847

848

849

850

851

852

853

854

855

856

857

858

859

860

861

862

863

864

865

866

867

868

869

870

871

872

873

874

875

876

877

878

879

880

881

882

883

884

885

886

887

888

889

890

891

892

893

894

895

896

897

898

899

900

901

902

903

904

905

906

907

908

909

910

911

912

913

914

915

916

917

918

919

920

921

922

923

924

925

926

927

928

929

930

931

932

933

934

935

936

937

938

939

940

941

942

943

944

945

946

947

948

949

950

951

952

953

954

955

956

957

958

959

960

961

962

963

964

965

966

967

968

969

970

971

972

973

974

975

976

977

978

979

980

981

982

983

984

985

986

987

988

989

990

991

992

993

994

995

996

997

998

999

1000

/* Execute compiled code */

/* XXX TO DO:

XXX speed up searching for keywords by using a dictionary

XXX document it!

#include "Python.h"

#include "pycore_abstract.h" // _PyIndex_Check()

#include "pycore_call.h" // _PyObject_FastCallDictTstate()

#include "pycore_ceval.h" // _PyEval_SignalAsyncExc()

#include "pycore_code.h"

#include "pycore_function.h"

#include "pycore_initconfig.h" // _PyStatus_OK()

#include "pycore_long.h" // _PyLong_GetZero()

#include "pycore_object.h" // _PyObject_GC_TRACK()

#include "pycore_moduleobject.h" // PyModuleObject

#include "pycore_opcode.h" // EXTRA_CASES

#include "pycore_pyerrors.h" // _PyErr_Fetch()

#include "pycore_pylifecycle.h" // _PyErr_Print()

#include "pycore_pymem.h" // _PyMem_IsPtrFreed()

#include "pycore_pystate.h" // _PyInterpreterState_GET()

#include "pycore_sysmodule.h" // _PySys_Audit()

#include "pycore_tuple.h" // _PyTuple_ITEMS()

#include "pycore_emscripten_signal.h" // _Py_CHECK_EMSCRIPTEN_SIGNALS

#include "pycore_dict.h"

#include "dictobject.h"

#include "pycore_frame.h"

#include "opcode.h"

#include "pydtrace.h"

#include "setobject.h"

#include "structmember.h" // struct PyMemberDef, T_OFFSET_EX

#include <ctype.h>

#include <stdbool.h>

#ifdef Py_DEBUG

/* For debugging the interpreter: */

# define LLTRACE 1 /* Low-level trace feature */

#endif

#if !defined(Py_BUILD_CORE)

# error "ceval.c must be build with Py_BUILD_CORE define for best performance"

#endif

#if !defined(Py_DEBUG) && !defined(Py_TRACE_REFS)

// GH-89279: The MSVC compiler does not inline these static inline functions

// in PGO build in _PyEval_EvalFrameDefault(), because this function is over

// the limit of PGO, and that limit cannot be configured.

// Define them as macros to make sure that they are always inlined by the

// preprocessor.

#undef Py_DECREF

#define Py_DECREF(arg) \

do { \

PyObject *op = _PyObject_CAST(arg); \

if (--op->ob_refcnt == 0) { \

destructor dealloc = Py_TYPE(op)->tp_dealloc; \

(*dealloc)(op); \

} \

} while (0)

#undef Py_XDECREF

#define Py_XDECREF(arg) \

do { \

PyObject *xop = _PyObject_CAST(arg); \

if (xop != NULL) { \

Py_DECREF(xop); \

} \

} while (0)

#undef Py_IS_TYPE

#define Py_IS_TYPE(ob, type) \

(_PyObject_CAST(ob)->ob_type == (type))

#undef _Py_DECREF_SPECIALIZED

#define _Py_DECREF_SPECIALIZED(arg, dealloc) \

do { \

PyObject *op = _PyObject_CAST(arg); \

if (--op->ob_refcnt == 0) { \

destructor d = (destructor)(dealloc); \

d(op); \

} \

} while (0)

#endif

// GH-89279: Similar to above, force inlining by using a macro.

#if defined(_MSC_VER) && SIZEOF_INT == 4

#define _Py_atomic_load_relaxed_int32(ATOMIC_VAL) (assert(sizeof((ATOMIC_VAL)->_value) == 4), *((volatile int*)&((ATOMIC_VAL)->_value)))

#else

#define _Py_atomic_load_relaxed_int32(ATOMIC_VAL) _Py_atomic_load_relaxed(ATOMIC_VAL)

#endif

/* Forward declarations */

static PyObject *trace_call_function(

PyThreadState *tstate, PyObject *callable, PyObject **stack,

Py_ssize_t oparg, PyObject *kwnames);

static PyObject * do_call_core(

PyThreadState *tstate, PyObject *func,

PyObject *callargs, PyObject *kwdict, int use_tracing);

#ifdef LLTRACE

static void

dump_stack(_PyInterpreterFrame *frame, PyObject **stack_pointer)

{

PyObject **stack_base = _PyFrame_Stackbase(frame);

PyObject *type, *value, *traceback;

PyErr_Fetch(&type, &value, &traceback);

printf(" stack=[");

for (PyObject **ptr = stack_base; ptr < stack_pointer; ptr++) {

if (ptr != stack_base) {

printf(", ");

}

if (PyObject_Print(*ptr, stdout, 0) != 0) {

PyErr_Clear();

printf("<%s object at %p>",

Py_TYPE(*ptr)->tp_name, (void *)(*ptr));

}

printf("]\n");

fflush(stdout);

PyErr_Restore(type, value, traceback);

}

static void

lltrace_instruction(_PyInterpreterFrame *frame,

PyObject **stack_pointer,

_Py_CODEUNIT *next_instr)

{

dump_stack(frame, stack_pointer);

int oparg = _Py_OPARG(*next_instr);

int opcode = _Py_OPCODE(*next_instr);

const char *opname = _PyOpcode_OpName[opcode];

assert(opname != NULL);

int offset = (int)(next_instr - _PyCode_CODE(frame->f_code));

if (HAS_ARG(opcode)) {

printf("%d: %s %d\n", offset * 2, opname, oparg);

}

else {

printf("%d: %s\n", offset * 2, opname);

}

fflush(stdout);

}

static void

lltrace_resume_frame(_PyInterpreterFrame *frame)

{

PyFunctionObject *f = frame->f_func;

if (f == NULL) {

printf("\nResuming frame.");

return;

}

PyObject *type, *value, *traceback;

PyErr_Fetch(&type, &value, &traceback);

PyObject *name = f->func_qualname;

if (name == NULL) {

name = f->func_name;

}

printf("\nResuming frame");

if (name) {

printf(" for ");

if (PyObject_Print(name, stdout, 0) < 0) {

PyErr_Clear();

}

if (f->func_module) {

printf(" in module ");

if (PyObject_Print(f->func_module, stdout, 0) < 0) {

PyErr_Clear();

}

printf("\n");

fflush(stdout);

PyErr_Restore(type, value, traceback);

}

#endif

static int call_trace(Py_tracefunc, PyObject *,

PyThreadState *, _PyInterpreterFrame *,

int, PyObject *);

static int call_trace_protected(Py_tracefunc, PyObject *,

PyThreadState *, _PyInterpreterFrame *,

int, PyObject *);

static void call_exc_trace(Py_tracefunc, PyObject *,

PyThreadState *, _PyInterpreterFrame *);

static int maybe_call_line_trace(Py_tracefunc, PyObject *,

PyThreadState *, _PyInterpreterFrame *, int);

static void maybe_dtrace_line(_PyInterpreterFrame *, PyTraceInfo *, int);

static void dtrace_function_entry(_PyInterpreterFrame *);

static void dtrace_function_return(_PyInterpreterFrame *);

static PyObject * import_name(PyThreadState *, _PyInterpreterFrame *,

PyObject *, PyObject *, PyObject *);

static PyObject * import_from(PyThreadState *, PyObject *, PyObject *);

static int import_all_from(PyThreadState *, PyObject *, PyObject *);

static void format_exc_check_arg(PyThreadState *, PyObject *, const char *, PyObject *);

static void format_exc_unbound(PyThreadState *tstate, PyCodeObject *co, int oparg);

static int check_args_iterable(PyThreadState *, PyObject *func, PyObject *vararg);

static int check_except_type_valid(PyThreadState *tstate, PyObject* right);

static int check_except_star_type_valid(PyThreadState *tstate, PyObject* right);

static void format_kwargs_error(PyThreadState *, PyObject *func, PyObject *kwargs);

static void format_awaitable_error(PyThreadState *, PyTypeObject *, int);

static int get_exception_handler(PyCodeObject *, int, int*, int*, int*);

static _PyInterpreterFrame *

_PyEvalFramePushAndInit(PyThreadState *tstate, PyFunctionObject *func,

PyObject *locals, PyObject* const* args,

size_t argcount, PyObject *kwnames);

static void

_PyEvalFrameClearAndPop(PyThreadState *tstate, _PyInterpreterFrame *frame);

#define NAME_ERROR_MSG \

"name '%.200s' is not defined"

#define UNBOUNDLOCAL_ERROR_MSG \

"cannot access local variable '%s' where it is not associated with a value"

#define UNBOUNDFREE_ERROR_MSG \

"cannot access free variable '%s' where it is not associated with a" \

" value in enclosing scope"

/* This can set eval_breaker to 0 even though gil_drop_request became

1. We believe this is all right because the eval loop will release

the GIL eventually anyway. */

static inline void

COMPUTE_EVAL_BREAKER(PyInterpreterState *interp,

struct _ceval_runtime_state *ceval,

struct _ceval_state *ceval2)

{

_Py_atomic_store_relaxed(&ceval2->eval_breaker,

_Py_atomic_load_relaxed_int32(&ceval2->gil_drop_request)

| (_Py_atomic_load_relaxed_int32(&ceval->signals_pending)

&& _Py_ThreadCanHandleSignals(interp))

| (_Py_atomic_load_relaxed_int32(&ceval2->pending.calls_to_do)

&& _Py_ThreadCanHandlePendingCalls())

| ceval2->pending.async_exc);

}

static inline void

SET_GIL_DROP_REQUEST(PyInterpreterState *interp)

{

struct _ceval_state *ceval2 = &interp->ceval;

_Py_atomic_store_relaxed(&ceval2->gil_drop_request, 1);

_Py_atomic_store_relaxed(&ceval2->eval_breaker, 1);

}

static inline void

RESET_GIL_DROP_REQUEST(PyInterpreterState *interp)

{

struct _ceval_runtime_state *ceval = &interp->runtime->ceval;

struct _ceval_state *ceval2 = &interp->ceval;

_Py_atomic_store_relaxed(&ceval2->gil_drop_request, 0);

COMPUTE_EVAL_BREAKER(interp, ceval, ceval2);

}

static inline void

SIGNAL_PENDING_CALLS(PyInterpreterState *interp)

{

struct _ceval_runtime_state *ceval = &interp->runtime->ceval;

struct _ceval_state *ceval2 = &interp->ceval;

_Py_atomic_store_relaxed(&ceval2->pending.calls_to_do, 1);

COMPUTE_EVAL_BREAKER(interp, ceval, ceval2);

}

static inline void

UNSIGNAL_PENDING_CALLS(PyInterpreterState *interp)

{

struct _ceval_runtime_state *ceval = &interp->runtime->ceval;

struct _ceval_state *ceval2 = &interp->ceval;

_Py_atomic_store_relaxed(&ceval2->pending.calls_to_do, 0);

COMPUTE_EVAL_BREAKER(interp, ceval, ceval2);

}

static inline void

SIGNAL_PENDING_SIGNALS(PyInterpreterState *interp, int force)

{

struct _ceval_runtime_state *ceval = &interp->runtime->ceval;

struct _ceval_state *ceval2 = &interp->ceval;

_Py_atomic_store_relaxed(&ceval->signals_pending, 1);

if (force) {

_Py_atomic_store_relaxed(&ceval2->eval_breaker, 1);

}

else {

/* eval_breaker is not set to 1 if thread_can_handle_signals() is false */

COMPUTE_EVAL_BREAKER(interp, ceval, ceval2);

}

static inline void

UNSIGNAL_PENDING_SIGNALS(PyInterpreterState *interp)

{

struct _ceval_runtime_state *ceval = &interp->runtime->ceval;

struct _ceval_state *ceval2 = &interp->ceval;

_Py_atomic_store_relaxed(&ceval->signals_pending, 0);

COMPUTE_EVAL_BREAKER(interp, ceval, ceval2);

}

static inline void

SIGNAL_ASYNC_EXC(PyInterpreterState *interp)

{

struct _ceval_state *ceval2 = &interp->ceval;

ceval2->pending.async_exc = 1;

_Py_atomic_store_relaxed(&ceval2->eval_breaker, 1);

}

static inline void

UNSIGNAL_ASYNC_EXC(PyInterpreterState *interp)

{

struct _ceval_runtime_state *ceval = &interp->runtime->ceval;

struct _ceval_state *ceval2 = &interp->ceval;

ceval2->pending.async_exc = 0;

COMPUTE_EVAL_BREAKER(interp, ceval, ceval2);

}

#ifdef HAVE_ERRNO_H

#include <errno.h>

#endif

#include "ceval_gil.h"

void _Py_NO_RETURN

_Py_FatalError_TstateNULL(const char *func)

{

_Py_FatalErrorFunc(func,

"the function must be called with the GIL held, "

"but the GIL is released "

"(the current Python thread state is NULL)");

}

int

_PyEval_ThreadsInitialized(_PyRuntimeState *runtime)

{

return gil_created(&runtime->ceval.gil);

}

int

PyEval_ThreadsInitialized(void)

{

_PyRuntimeState *runtime = &_PyRuntime;

return _PyEval_ThreadsInitialized(runtime);

}

PyStatus

_PyEval_InitGIL(PyThreadState *tstate)

{

if (!_Py_IsMainInterpreter(tstate->interp)) {

/* Currently, the GIL is shared by all interpreters,

and only the main interpreter is responsible to create

and destroy it. */

return _PyStatus_OK();

}

struct _gil_runtime_state *gil = &tstate->interp->runtime->ceval.gil;

assert(!gil_created(gil));

PyThread_init_thread();

create_gil(gil);

take_gil(tstate);

assert(gil_created(gil));

return _PyStatus_OK();

}

void

_PyEval_FiniGIL(PyInterpreterState *interp)

{

if (!_Py_IsMainInterpreter(interp)) {

/* Currently, the GIL is shared by all interpreters,

and only the main interpreter is responsible to create

and destroy it. */

return;

}

struct _gil_runtime_state *gil = &interp->runtime->ceval.gil;

if (!gil_created(gil)) {

/* First Py_InitializeFromConfig() call: the GIL doesn't exist

yet: do nothing. */

return;

}

destroy_gil(gil);

assert(!gil_created(gil));

}

void

PyEval_InitThreads(void)

{

/* Do nothing: kept for backward compatibility */

}

void

_PyEval_Fini(void)

{

#ifdef Py_STATS

_Py_PrintSpecializationStats(1);

#endif

}

void

PyEval_AcquireLock(void)

{

_PyRuntimeState *runtime = &_PyRuntime;

PyThreadState *tstate = _PyRuntimeState_GetThreadState(runtime);

_Py_EnsureTstateNotNULL(tstate);

take_gil(tstate);

}

void

PyEval_ReleaseLock(void)

{

_PyRuntimeState *runtime = &_PyRuntime;

PyThreadState *tstate = _PyRuntimeState_GetThreadState(runtime);

/* This function must succeed when the current thread state is NULL.

We therefore avoid PyThreadState_Get() which dumps a fatal error

in debug mode. */

struct _ceval_runtime_state *ceval = &runtime->ceval;

struct _ceval_state *ceval2 = &tstate->interp->ceval;

drop_gil(ceval, ceval2, tstate);

}

void

_PyEval_ReleaseLock(PyThreadState *tstate)

{

struct _ceval_runtime_state *ceval = &tstate->interp->runtime->ceval;

struct _ceval_state *ceval2 = &tstate->interp->ceval;

drop_gil(ceval, ceval2, tstate);

}

void

PyEval_AcquireThread(PyThreadState *tstate)

{

_Py_EnsureTstateNotNULL(tstate);

take_gil(tstate);

struct _gilstate_runtime_state *gilstate = &tstate->interp->runtime->gilstate;

if (_PyThreadState_Swap(gilstate, tstate) != NULL) {

Py_FatalError("non-NULL old thread state");

}

void

PyEval_ReleaseThread(PyThreadState *tstate)

{

assert(_PyThreadState_CheckConsistency(tstate));

_PyRuntimeState *runtime = tstate->interp->runtime;

PyThreadState *new_tstate = _PyThreadState_Swap(&runtime->gilstate, NULL);

if (new_tstate != tstate) {

Py_FatalError("wrong thread state");

}

struct _ceval_runtime_state *ceval = &runtime->ceval;

struct _ceval_state *ceval2 = &tstate->interp->ceval;

drop_gil(ceval, ceval2, tstate);

}

#ifdef HAVE_FORK

/* This function is called from PyOS_AfterFork_Child to destroy all threads

which are not running in the child process, and clear internal locks

which might be held by those threads. */

PyStatus

_PyEval_ReInitThreads(PyThreadState *tstate)

{

_PyRuntimeState *runtime = tstate->interp->runtime;

struct _gil_runtime_state *gil = &runtime->ceval.gil;

if (!gil_created(gil)) {

return _PyStatus_OK();

}

recreate_gil(gil);

take_gil(tstate);

struct _pending_calls *pending = &tstate->interp->ceval.pending;

if (_PyThread_at_fork_reinit(&pending->lock) < 0) {

return _PyStatus_ERR("Can't reinitialize pending calls lock");

}

/* Destroy all threads except the current one */

_PyThreadState_DeleteExcept(runtime, tstate);

return _PyStatus_OK();

}

#endif

/* This function is used to signal that async exceptions are waiting to be

raised. */

void

_PyEval_SignalAsyncExc(PyInterpreterState *interp)

{

SIGNAL_ASYNC_EXC(interp);

}

PyThreadState *

PyEval_SaveThread(void)

{

_PyRuntimeState *runtime = &_PyRuntime;

PyThreadState *tstate = _PyThreadState_Swap(&runtime->gilstate, NULL);

_Py_EnsureTstateNotNULL(tstate);

struct _ceval_runtime_state *ceval = &runtime->ceval;

struct _ceval_state *ceval2 = &tstate->interp->ceval;

assert(gil_created(&ceval->gil));

drop_gil(ceval, ceval2, tstate);

return tstate;

}

void

PyEval_RestoreThread(PyThreadState *tstate)

{

_Py_EnsureTstateNotNULL(tstate);

take_gil(tstate);

struct _gilstate_runtime_state *gilstate = &tstate->interp->runtime->gilstate;

_PyThreadState_Swap(gilstate, tstate);

}

/* Mechanism whereby asynchronously executing callbacks (e.g. UNIX

signal handlers or Mac I/O completion routines) can schedule calls

to a function to be called synchronously.

The synchronous function is called with one void* argument.

It should return 0 for success or -1 for failure -- failure should

be accompanied by an exception.

If registry succeeds, the registry function returns 0; if it fails

(e.g. due to too many pending calls) it returns -1 (without setting

an exception condition).

Note that because registry may occur from within signal handlers,

or other asynchronous events, calling malloc() is unsafe!

Any thread can schedule pending calls, but only the main thread

will execute them.

There is no facility to schedule calls to a particular thread, but

that should be easy to change, should that ever be required. In

that case, the static variables here should go into the python

threadstate.

void

_PyEval_SignalReceived(PyInterpreterState *interp)

{

#ifdef MS_WINDOWS

// bpo-42296: On Windows, _PyEval_SignalReceived() is called from a signal

// handler which can run in a thread different than the Python thread, in

// which case _Py_ThreadCanHandleSignals() is wrong. Ignore

// _Py_ThreadCanHandleSignals() and always set eval_breaker to 1.

// The next eval_frame_handle_pending() call will call

// _Py_ThreadCanHandleSignals() to recompute eval_breaker.

int force = 1;

#else

int force = 0;

#endif

/* bpo-30703: Function called when the C signal handler of Python gets a

signal. We cannot queue a callback using _PyEval_AddPendingCall() since

that function is not async-signal-safe. */

SIGNAL_PENDING_SIGNALS(interp, force);

}

/* Push one item onto the queue while holding the lock. */

static int

_push_pending_call(struct _pending_calls *pending,

int (*func)(void *), void *arg)

{

int i = pending->last;

int j = (i + 1) % NPENDINGCALLS;

if (j == pending->first) {

return -1; /* Queue full */

}

pending->calls[i].func = func;

pending->calls[i].arg = arg;

pending->last = j;

return 0;

}

/* Pop one item off the queue while holding the lock. */

static void

_pop_pending_call(struct _pending_calls *pending,

int (**func)(void *), void **arg)

{

int i = pending->first;

if (i == pending->last) {

return; /* Queue empty */

}

*func = pending->calls[i].func;

*arg = pending->calls[i].arg;

pending->first = (i + 1) % NPENDINGCALLS;

}

/* This implementation is thread-safe. It allows

scheduling to be made from any thread, and even from an executing

callback.

int

_PyEval_AddPendingCall(PyInterpreterState *interp,

int (*func)(void *), void *arg)

{

struct _pending_calls *pending = &interp->ceval.pending;

/* Ensure that _PyEval_InitPendingCalls() was called

and that _PyEval_FiniPendingCalls() is not called yet. */

assert(pending->lock != NULL);

PyThread_acquire_lock(pending->lock, WAIT_LOCK);

int result = _push_pending_call(pending, func, arg);

PyThread_release_lock(pending->lock);

/* signal main loop */

SIGNAL_PENDING_CALLS(interp);

return result;

}

int

Py_AddPendingCall(int (*func)(void *), void *arg)

{

/* Best-effort to support subinterpreters and calls with the GIL released.

First attempt _PyThreadState_GET() since it supports subinterpreters.

If the GIL is released, _PyThreadState_GET() returns NULL . In this

case, use PyGILState_GetThisThreadState() which works even if the GIL

is released.

Sadly, PyGILState_GetThisThreadState() doesn't support subinterpreters:

see bpo-10915 and bpo-15751.

Py_AddPendingCall() doesn't require the caller to hold the GIL. */

PyThreadState *tstate = _PyThreadState_GET();

if (tstate == NULL) {

tstate = PyGILState_GetThisThreadState();

}

PyInterpreterState *interp;

if (tstate != NULL) {

interp = tstate->interp;

}

else {

/* Last resort: use the main interpreter */

interp = _PyInterpreterState_Main();

}

return _PyEval_AddPendingCall(interp, func, arg);

}

static int

handle_signals(PyThreadState *tstate)

{

assert(_PyThreadState_CheckConsistency(tstate));

if (!_Py_ThreadCanHandleSignals(tstate->interp)) {

return 0;

}

UNSIGNAL_PENDING_SIGNALS(tstate->interp);

if (_PyErr_CheckSignalsTstate(tstate) < 0) {

/* On failure, re-schedule a call to handle_signals(). */

SIGNAL_PENDING_SIGNALS(tstate->interp, 0);

return -1;

}

return 0;

}

static int

make_pending_calls(PyInterpreterState *interp)

{

/* only execute pending calls on main thread */

if (!_Py_ThreadCanHandlePendingCalls()) {

return 0;

}

/* don't perform recursive pending calls */

static int busy = 0;

if (busy) {

return 0;

}

busy = 1;

/* unsignal before starting to call callbacks, so that any callback

added in-between re-signals */

UNSIGNAL_PENDING_CALLS(interp);

int res = 0;

/* perform a bounded number of calls, in case of recursion */

struct _pending_calls *pending = &interp->ceval.pending;

for (int i=0; i<NPENDINGCALLS; i++) {

int (*func)(void *) = NULL;

void *arg = NULL;

/* pop one item off the queue while holding the lock */

PyThread_acquire_lock(pending->lock, WAIT_LOCK);

_pop_pending_call(pending, &func, &arg);

PyThread_release_lock(pending->lock);

/* having released the lock, perform the callback */

if (func == NULL) {

break;

}

res = func(arg);

if (res) {

goto error;

}

busy = 0;

return res;

error:

busy = 0;

SIGNAL_PENDING_CALLS(interp);

return res;

}

void

_Py_FinishPendingCalls(PyThreadState *tstate)

{

assert(PyGILState_Check());

assert(_PyThreadState_CheckConsistency(tstate));

struct _pending_calls *pending = &tstate->interp->ceval.pending;

if (!_Py_atomic_load_relaxed_int32(&(pending->calls_to_do))) {

return;

}

if (make_pending_calls(tstate->interp) < 0) {

PyObject *exc, *val, *tb;

_PyErr_Fetch(tstate, &exc, &val, &tb);

PyErr_BadInternalCall();

_PyErr_ChainExceptions(exc, val, tb);

_PyErr_Print(tstate);

}

/* Py_MakePendingCalls() is a simple wrapper for the sake

of backward-compatibility. */

int

Py_MakePendingCalls(void)

{

assert(PyGILState_Check());

PyThreadState *tstate = _PyThreadState_GET();

assert(_PyThreadState_CheckConsistency(tstate));

/* Python signal handler doesn't really queue a callback: it only signals

that a signal was received, see _PyEval_SignalReceived(). */

int res = handle_signals(tstate);

if (res != 0) {

return res;

}

res = make_pending_calls(tstate->interp);

if (res != 0) {

return res;

}

return 0;

}

/* The interpreter's recursion limit */

void

_PyEval_InitRuntimeState(struct _ceval_runtime_state *ceval)

{

_gil_initialize(&ceval->gil);

}

void

_PyEval_InitState(struct _ceval_state *ceval, PyThread_type_lock pending_lock)

{

struct _pending_calls *pending = &ceval->pending;

assert(pending->lock == NULL);

pending->lock = pending_lock;

}

void

_PyEval_FiniState(struct _ceval_state *ceval)

{

struct _pending_calls *pending = &ceval->pending;

if (pending->lock != NULL) {

PyThread_free_lock(pending->lock);

pending->lock = NULL;

}

int

Py_GetRecursionLimit(void)

{

PyInterpreterState *interp = _PyInterpreterState_GET();

return interp->ceval.recursion_limit;

}

void

Py_SetRecursionLimit(int new_limit)

{

PyInterpreterState *interp = _PyInterpreterState_GET();

interp->ceval.recursion_limit = new_limit;

for (PyThreadState *p = interp->threads.head; p != NULL; p = p->next) {

int depth = p->recursion_limit - p->recursion_remaining;

p->recursion_limit = new_limit;

p->recursion_remaining = new_limit - depth;

}

/* The function _Py_EnterRecursiveCallTstate() only calls _Py_CheckRecursiveCall()

if the recursion_depth reaches recursion_limit. */

int

_Py_CheckRecursiveCall(PyThreadState *tstate, const char *where)

{

/* Check against global limit first. */

int depth = tstate->recursion_limit - tstate->recursion_remaining;

if (depth < tstate->interp->ceval.recursion_limit) {

tstate->recursion_limit = tstate->interp->ceval.recursion_limit;

tstate->recursion_remaining = tstate->recursion_limit - depth;

assert(tstate->recursion_remaining > 0);

return 0;

}

#ifdef USE_STACKCHECK

if (PyOS_CheckStack()) {

++tstate->recursion_remaining;

_PyErr_SetString(tstate, PyExc_MemoryError, "Stack overflow");

return -1;

}

#endif

if (tstate->recursion_headroom) {

if (tstate->recursion_remaining < -50) {

/* Overflowing while handling an overflow. Give up. */

Py_FatalError("Cannot recover from stack overflow.");

}

else {

if (tstate->recursion_remaining <= 0) {

tstate->recursion_headroom++;

_PyErr_Format(tstate, PyExc_RecursionError,

"maximum recursion depth exceeded%s",

where);

tstate->recursion_headroom--;

++tstate->recursion_remaining;

return -1;

}

return 0;

}

static const binaryfunc binary_ops[] = {

[NB_ADD] = PyNumber_Add,

[NB_AND] = PyNumber_And,

[NB_FLOOR_DIVIDE] = PyNumber_FloorDivide,

[NB_LSHIFT] = PyNumber_Lshift,

[NB_MATRIX_MULTIPLY] = PyNumber_MatrixMultiply,

[NB_MULTIPLY] = PyNumber_Multiply,

[NB_REMAINDER] = PyNumber_Remainder,

[NB_OR] = PyNumber_Or,

[NB_POWER] = _PyNumber_PowerNoMod,

[NB_RSHIFT] = PyNumber_Rshift,

[NB_SUBTRACT] = PyNumber_Subtract,

[NB_TRUE_DIVIDE] = PyNumber_TrueDivide,

[NB_XOR] = PyNumber_Xor,

[NB_INPLACE_ADD] = PyNumber_InPlaceAdd,

[NB_INPLACE_AND] = PyNumber_InPlaceAnd,

[NB_INPLACE_FLOOR_DIVIDE] = PyNumber_InPlaceFloorDivide,

[NB_INPLACE_LSHIFT] = PyNumber_InPlaceLshift,

[NB_INPLACE_MATRIX_MULTIPLY] = PyNumber_InPlaceMatrixMultiply,

[NB_INPLACE_MULTIPLY] = PyNumber_InPlaceMultiply,

[NB_INPLACE_REMAINDER] = PyNumber_InPlaceRemainder,

[NB_INPLACE_OR] = PyNumber_InPlaceOr,

[NB_INPLACE_POWER] = _PyNumber_InPlacePowerNoMod,

[NB_INPLACE_RSHIFT] = PyNumber_InPlaceRshift,

[NB_INPLACE_SUBTRACT] = PyNumber_InPlaceSubtract,

[NB_INPLACE_TRUE_DIVIDE] = PyNumber_InPlaceTrueDivide,

[NB_INPLACE_XOR] = PyNumber_InPlaceXor,

};

// PEP 634: Structural Pattern Matching

// Return a tuple of values corresponding to keys, with error checks for

// duplicate/missing keys.

static PyObject*

match_keys(PyThreadState *tstate, PyObject *map, PyObject *keys)

{

assert(PyTuple_CheckExact(keys));

Py_ssize_t nkeys = PyTuple_GET_SIZE(keys);

if (!nkeys) {

// No keys means no items.

return PyTuple_New(0);

}

PyObject *seen = NULL;

PyObject *dummy = NULL;

PyObject *values = NULL;

PyObject *get = NULL;

// We use the two argument form of map.get(key, default) for two reasons:

// - Atomically check for a key and get its value without error handling.

// - Don't cause key creation or resizing in dict subclasses like

// collections.defaultdict that define __missing__ (or similar).

int meth_found = _PyObject_GetMethod(map, &_Py_ID(get), &get);

if (get == NULL) {

goto fail;

}

seen = PySet_New(NULL);

if (seen == NULL) {

goto fail;

}

// dummy = object()

dummy = _PyObject_CallNoArgs((PyObject *)&PyBaseObject_Type);

if (dummy == NULL) {

goto fail;

}

values = PyTuple_New(nkeys);

if (values == NULL) {

goto fail;

}

for (Py_ssize_t i = 0; i < nkeys; i++) {

PyObject *key = PyTuple_GET_ITEM(keys, i);

if (PySet_Contains(seen, key) || PySet_Add(seen, key)) {

if (!_PyErr_Occurred(tstate)) {

// Seen it before!

_PyErr_Format(tstate, PyExc_ValueError,

"mapping pattern checks duplicate key (%R)", key);

}

goto fail;

}

PyObject *args[] = { map, key, dummy };

PyObject *value = NULL;

if (meth_found) {

value = PyObject_Vectorcall(get, args, 3, NULL);

}

else {

value = PyObject_Vectorcall(get, &args[1], 2, NULL);

}

if (value == NULL) {

goto fail;

}

if (value == dummy) {

// key not in map!

Py_DECREF(value);

Py_DECREF(values);

// Return None:

Py_INCREF(Py_None);

values = Py_None;

goto done;

}

PyTuple_SET_ITEM(values, i, value);

}

// Success:

done:

Py_DECREF(get);

Py_DECREF(seen);

Py_DECREF(dummy);

return values;

fail:

Py_XDECREF(get);

Py_XDECREF(seen);

Py_XDECREF(dummy);

Py_XDECREF(values);

return NULL;

}

// Extract a named attribute from the subject, with additional bookkeeping to

// raise TypeErrors for repeated lookups. On failure, return NULL (with no

// error set). Use _PyErr_Occurred(tstate) to disambiguate.

static PyObject*

match_class_attr(PyThreadState *tstate, PyObject *subject, PyObject *type,

PyObject *name, PyObject *seen)

{

assert(PyUnicode_CheckExact(name));

assert(PySet_CheckExact(seen));

if (PySet_Contains(seen, name) || PySet_Add(seen, name)) {

if (!_PyErr_Occurred(tstate)) {

// Seen it before!

_PyErr_Format(tstate, PyExc_TypeError,

"%s() got multiple sub-patterns for attribute %R",

((PyTypeObject*)type)->tp_name, name);

}

return NULL;

}

PyObject *attr = PyObject_GetAttr(subject, name);

if (attr == NULL && _PyErr_ExceptionMatches(tstate, PyExc_AttributeError)) {

_PyErr_Clear(tstate);

}

return attr;

}

// On success (match), return a tuple of extracted attributes. On failure (no

// match), return NULL. Use _PyErr_Occurred(tstate) to disambiguate.

static PyObject*

match_class(PyThreadState *tstate, PyObject *subject, PyObject *type,

View remainder of file in raw view

cpython/Python/ceval.c at 3.11 · python/cpython · GitHub

Navigation Menu

Repository navigation

Expand file tree

Breadcrumbs

ceval.c

Latest commit

History

Breadcrumbs

ceval.c

File metadata and controls

Footer

Footer navigation