cpython/Python/marshal.c at 1388dd0a28046a15a7890f6d4082c87b98c65757 · python/cpython · GitHub

History

1898 lines (1736 loc) · 50.5 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

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

/* Write Python objects to files and read them back.

This is primarily intended for writing and reading compiled Python code,

even though dicts, lists, sets and frozensets, not commonly seen in

code objects, are supported.

Version 3 of this protocol properly supports circular links

and sharing. */

#define PY_SSIZE_T_CLEAN

#include "Python.h"

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

#include "pycore_code.h" // _PyCode_New()

#include "pycore_hashtable.h" // _Py_hashtable_t

#include "marshal.h" // Py_MARSHAL_VERSION

/*[clinic input]

module marshal

[clinic start generated code]*/

/*[clinic end generated code: output=da39a3ee5e6b4b0d input=c982b7930dee17db]*/

#include "clinic/marshal.c.h"

/* High water mark to determine when the marshalled object is dangerously deep

* and risks coring the interpreter. When the object stack gets this deep,

* raise an exception instead of continuing.

* On Windows debug builds, reduce this value.

* BUG: https://bugs.python.org/issue33720

* On Windows PGO builds, the r_object function overallocates its stack and

* can cause a stack overflow. We reduce the maximum depth for all Windows

* releases to protect against this.

* #if defined(MS_WINDOWS) && defined(_DEBUG)

#if defined(MS_WINDOWS)

#define MAX_MARSHAL_STACK_DEPTH 1000

#elif defined(__wasi__)

#define MAX_MARSHAL_STACK_DEPTH 1500

#else

#define MAX_MARSHAL_STACK_DEPTH 2000

#endif

#define TYPE_NULL '0'

#define TYPE_NONE 'N'

#define TYPE_FALSE 'F'

#define TYPE_TRUE 'T'

#define TYPE_STOPITER 'S'

#define TYPE_ELLIPSIS '.'

#define TYPE_INT 'i'

/* TYPE_INT64 is not generated anymore.

Supported for backward compatibility only. */

#define TYPE_INT64 'I'

#define TYPE_FLOAT 'f'

#define TYPE_BINARY_FLOAT 'g'

#define TYPE_COMPLEX 'x'

#define TYPE_BINARY_COMPLEX 'y'

#define TYPE_LONG 'l'

#define TYPE_STRING 's'

#define TYPE_INTERNED 't'

#define TYPE_REF 'r'

#define TYPE_TUPLE '('

#define TYPE_LIST '['

#define TYPE_DICT '{'

#define TYPE_CODE 'c'

#define TYPE_UNICODE 'u'

#define TYPE_UNKNOWN '?'

#define TYPE_SET '<'

#define TYPE_FROZENSET '>'

#define FLAG_REF '\x80' /* with a type, add obj to index */

#define TYPE_ASCII 'a'

#define TYPE_ASCII_INTERNED 'A'

#define TYPE_SMALL_TUPLE ')'

#define TYPE_SHORT_ASCII 'z'

#define TYPE_SHORT_ASCII_INTERNED 'Z'

#define WFERR_OK 0

#define WFERR_UNMARSHALLABLE 1

#define WFERR_NESTEDTOODEEP 2

#define WFERR_NOMEMORY 3

typedef struct {

FILE *fp;

int error; /* see WFERR_* values */

int depth;

PyObject *str;

char *ptr;

const char *end;

char *buf;

_Py_hashtable_t *hashtable;

int version;

} WFILE;

#define w_byte(c, p) do { \

if ((p)->ptr != (p)->end || w_reserve((p), 1)) \

*(p)->ptr++ = (c); \

} while(0)

static void

w_flush(WFILE *p)

{

assert(p->fp != NULL);

fwrite(p->buf, 1, p->ptr - p->buf, p->fp);

p->ptr = p->buf;

}

static int

w_reserve(WFILE *p, Py_ssize_t needed)

{

Py_ssize_t pos, size, delta;

if (p->ptr == NULL)

return 0; /* An error already occurred */

if (p->fp != NULL) {

w_flush(p);

return needed <= p->end - p->ptr;

}

assert(p->str != NULL);

pos = p->ptr - p->buf;

size = PyBytes_GET_SIZE(p->str);

if (size > 16*1024*1024)

delta = (size >> 3); /* 12.5% overallocation */

else

delta = size + 1024;

delta = Py_MAX(delta, needed);

if (delta > PY_SSIZE_T_MAX - size) {

p->error = WFERR_NOMEMORY;

return 0;

}

size += delta;

if (_PyBytes_Resize(&p->str, size) != 0) {

p->end = p->ptr = p->buf = NULL;

return 0;

}

else {

p->buf = PyBytes_AS_STRING(p->str);

p->ptr = p->buf + pos;

p->end = p->buf + size;

return 1;

}

static void

w_string(const void *s, Py_ssize_t n, WFILE *p)

{

Py_ssize_t m;

if (!n || p->ptr == NULL)

return;

m = p->end - p->ptr;

if (p->fp != NULL) {

if (n <= m) {

memcpy(p->ptr, s, n);

p->ptr += n;

}

else {

w_flush(p);

fwrite(s, 1, n, p->fp);

}

else {

if (n <= m || w_reserve(p, n - m)) {

memcpy(p->ptr, s, n);

p->ptr += n;

}

static void

w_short(int x, WFILE *p)

{

w_byte((char)( x & 0xff), p);

w_byte((char)((x>> 8) & 0xff), p);

}

static void

w_long(long x, WFILE *p)

{

w_byte((char)( x & 0xff), p);

w_byte((char)((x>> 8) & 0xff), p);

w_byte((char)((x>>16) & 0xff), p);

w_byte((char)((x>>24) & 0xff), p);

}

#define SIZE32_MAX 0x7FFFFFFF

#if SIZEOF_SIZE_T > 4

# define W_SIZE(n, p) do { \

if ((n) > SIZE32_MAX) { \

(p)->depth--; \

(p)->error = WFERR_UNMARSHALLABLE; \

return; \

} \

w_long((long)(n), p); \

} while(0)

#else

# define W_SIZE w_long

#endif

static void

w_pstring(const void *s, Py_ssize_t n, WFILE *p)

{

W_SIZE(n, p);

w_string(s, n, p);

}

static void

w_short_pstring(const void *s, Py_ssize_t n, WFILE *p)

{

w_byte(Py_SAFE_DOWNCAST(n, Py_ssize_t, unsigned char), p);

w_string(s, n, p);

}

/* We assume that Python ints are stored internally in base some power of

2**15; for the sake of portability we'll always read and write them in base

exactly 2**15. */

#define PyLong_MARSHAL_SHIFT 15

#define PyLong_MARSHAL_BASE ((short)1 << PyLong_MARSHAL_SHIFT)

#define PyLong_MARSHAL_MASK (PyLong_MARSHAL_BASE - 1)

#if PyLong_SHIFT % PyLong_MARSHAL_SHIFT != 0

#error "PyLong_SHIFT must be a multiple of PyLong_MARSHAL_SHIFT"

#endif

#define PyLong_MARSHAL_RATIO (PyLong_SHIFT / PyLong_MARSHAL_SHIFT)

#define W_TYPE(t, p) do { \

w_byte((t) | flag, (p)); \

} while(0)

static void

w_PyLong(const PyLongObject *ob, char flag, WFILE *p)

{

Py_ssize_t i, j, n, l;

digit d;

W_TYPE(TYPE_LONG, p);

if (Py_SIZE(ob) == 0) {

w_long((long)0, p);

return;

}

/* set l to number of base PyLong_MARSHAL_BASE digits */

n = Py_ABS(Py_SIZE(ob));

l = (n-1) * PyLong_MARSHAL_RATIO;

d = ob->ob_digit[n-1];

assert(d != 0); /* a PyLong is always normalized */

do {

d >>= PyLong_MARSHAL_SHIFT;

l++;

} while (d != 0);

if (l > SIZE32_MAX) {

p->depth--;

p->error = WFERR_UNMARSHALLABLE;

return;

}

w_long((long)(Py_SIZE(ob) > 0 ? l : -l), p);

for (i=0; i < n-1; i++) {

d = ob->ob_digit[i];

for (j=0; j < PyLong_MARSHAL_RATIO; j++) {

w_short(d & PyLong_MARSHAL_MASK, p);

d >>= PyLong_MARSHAL_SHIFT;

}

assert (d == 0);

}

d = ob->ob_digit[n-1];

do {

w_short(d & PyLong_MARSHAL_MASK, p);

d >>= PyLong_MARSHAL_SHIFT;

} while (d != 0);

}

static void

w_float_bin(double v, WFILE *p)

{

char buf[8];

if (PyFloat_Pack8(v, buf, 1) < 0) {

p->error = WFERR_UNMARSHALLABLE;

return;

}

w_string(buf, 8, p);

}

static void

w_float_str(double v, WFILE *p)

{

char *buf = PyOS_double_to_string(v, 'g', 17, 0, NULL);

if (!buf) {

p->error = WFERR_NOMEMORY;

return;

}

w_short_pstring(buf, strlen(buf), p);

PyMem_Free(buf);

}

static int

w_ref(PyObject *v, char *flag, WFILE *p)

{

_Py_hashtable_entry_t *entry;

int w;

if (p->version < 3 || p->hashtable == NULL)

return 0; /* not writing object references */

/* If it has only one reference, it definitely isn't shared.

* But we use TYPE_REF always for interned string, to PYC file stable

* as possible.

if (Py_REFCNT(v) == 1 &&

!(PyUnicode_CheckExact(v) && PyUnicode_CHECK_INTERNED(v))) {

return 0;

}

entry = _Py_hashtable_get_entry(p->hashtable, v);

if (entry != NULL) {

/* write the reference index to the stream */

w = (int)(uintptr_t)entry->value;

/* we don't store "long" indices in the dict */

assert(0 <= w && w <= 0x7fffffff);

w_byte(TYPE_REF, p);

w_long(w, p);

return 1;

} else {

size_t s = p->hashtable->nentries;

/* we don't support long indices */

if (s >= 0x7fffffff) {

PyErr_SetString(PyExc_ValueError, "too many objects");

goto err;

}

w = (int)s;

Py_INCREF(v);

if (_Py_hashtable_set(p->hashtable, v, (void *)(uintptr_t)w) < 0) {

Py_DECREF(v);

goto err;

}

*flag |= FLAG_REF;

return 0;

}

err:

p->error = WFERR_UNMARSHALLABLE;

return 1;

}

static void

w_complex_object(PyObject *v, char flag, WFILE *p);

static void

w_object(PyObject *v, WFILE *p)

{

char flag = '\0';

p->depth++;

if (p->depth > MAX_MARSHAL_STACK_DEPTH) {

p->error = WFERR_NESTEDTOODEEP;

}

else if (v == NULL) {

w_byte(TYPE_NULL, p);

}

else if (v == Py_None) {

w_byte(TYPE_NONE, p);

}

else if (v == PyExc_StopIteration) {

w_byte(TYPE_STOPITER, p);

}

else if (v == Py_Ellipsis) {

w_byte(TYPE_ELLIPSIS, p);

}

else if (v == Py_False) {

w_byte(TYPE_FALSE, p);

}

else if (v == Py_True) {

w_byte(TYPE_TRUE, p);

}

else if (!w_ref(v, &flag, p))

w_complex_object(v, flag, p);

p->depth--;

}

static void

w_complex_object(PyObject *v, char flag, WFILE *p)

{

Py_ssize_t i, n;

if (PyLong_CheckExact(v)) {

int overflow;

long x = PyLong_AsLongAndOverflow(v, &overflow);

if (overflow) {

w_PyLong((PyLongObject *)v, flag, p);

}

else {

#if SIZEOF_LONG > 4

long y = Py_ARITHMETIC_RIGHT_SHIFT(long, x, 31);

if (y && y != -1) {

/* Too large for TYPE_INT */

w_PyLong((PyLongObject*)v, flag, p);

}

else

#endif

{

W_TYPE(TYPE_INT, p);

w_long(x, p);

}

else if (PyFloat_CheckExact(v)) {

if (p->version > 1) {

W_TYPE(TYPE_BINARY_FLOAT, p);

w_float_bin(PyFloat_AS_DOUBLE(v), p);

}

else {

W_TYPE(TYPE_FLOAT, p);

w_float_str(PyFloat_AS_DOUBLE(v), p);

}

else if (PyComplex_CheckExact(v)) {

if (p->version > 1) {

W_TYPE(TYPE_BINARY_COMPLEX, p);

w_float_bin(PyComplex_RealAsDouble(v), p);

w_float_bin(PyComplex_ImagAsDouble(v), p);

}

else {

W_TYPE(TYPE_COMPLEX, p);

w_float_str(PyComplex_RealAsDouble(v), p);

w_float_str(PyComplex_ImagAsDouble(v), p);

}

else if (PyBytes_CheckExact(v)) {

W_TYPE(TYPE_STRING, p);

w_pstring(PyBytes_AS_STRING(v), PyBytes_GET_SIZE(v), p);

}

else if (PyUnicode_CheckExact(v)) {

if (p->version >= 4 && PyUnicode_IS_ASCII(v)) {

int is_short = PyUnicode_GET_LENGTH(v) < 256;

if (is_short) {

if (PyUnicode_CHECK_INTERNED(v))

W_TYPE(TYPE_SHORT_ASCII_INTERNED, p);

else

W_TYPE(TYPE_SHORT_ASCII, p);

w_short_pstring(PyUnicode_1BYTE_DATA(v),

PyUnicode_GET_LENGTH(v), p);

}

else {

if (PyUnicode_CHECK_INTERNED(v))

W_TYPE(TYPE_ASCII_INTERNED, p);

else

W_TYPE(TYPE_ASCII, p);

w_pstring(PyUnicode_1BYTE_DATA(v),

PyUnicode_GET_LENGTH(v), p);

}

else {

PyObject *utf8;

utf8 = PyUnicode_AsEncodedString(v, "utf8", "surrogatepass");

if (utf8 == NULL) {

p->depth--;

p->error = WFERR_UNMARSHALLABLE;

return;

}

if (p->version >= 3 && PyUnicode_CHECK_INTERNED(v))

W_TYPE(TYPE_INTERNED, p);

else

W_TYPE(TYPE_UNICODE, p);

w_pstring(PyBytes_AS_STRING(utf8), PyBytes_GET_SIZE(utf8), p);

Py_DECREF(utf8);

}

else if (PyTuple_CheckExact(v)) {

n = PyTuple_GET_SIZE(v);

if (p->version >= 4 && n < 256) {

W_TYPE(TYPE_SMALL_TUPLE, p);

w_byte((unsigned char)n, p);

}

else {

W_TYPE(TYPE_TUPLE, p);

W_SIZE(n, p);

}

for (i = 0; i < n; i++) {

w_object(PyTuple_GET_ITEM(v, i), p);

}

else if (PyList_CheckExact(v)) {

W_TYPE(TYPE_LIST, p);

n = PyList_GET_SIZE(v);

W_SIZE(n, p);

for (i = 0; i < n; i++) {

w_object(PyList_GET_ITEM(v, i), p);

}

else if (PyDict_CheckExact(v)) {

Py_ssize_t pos;

PyObject *key, *value;

W_TYPE(TYPE_DICT, p);

/* This one is NULL object terminated! */

pos = 0;

while (PyDict_Next(v, &pos, &key, &value)) {

w_object(key, p);

w_object(value, p);

}

w_object((PyObject *)NULL, p);

}

else if (PyAnySet_CheckExact(v)) {

PyObject *value;

Py_ssize_t pos = 0;

Py_hash_t hash;

if (PyFrozenSet_CheckExact(v))

W_TYPE(TYPE_FROZENSET, p);

else

W_TYPE(TYPE_SET, p);

n = PySet_GET_SIZE(v);

W_SIZE(n, p);

// bpo-37596: To support reproducible builds, sets and frozensets need

// to have their elements serialized in a consistent order (even when

// they have been scrambled by hash randomization). To ensure this, we

// use an order equivalent to sorted(v, key=marshal.dumps):

PyObject *pairs = PyList_New(n);

if (pairs == NULL) {

p->error = WFERR_NOMEMORY;

return;

}

Py_ssize_t i = 0;

while (_PySet_NextEntry(v, &pos, &value, &hash)) {

PyObject *dump = PyMarshal_WriteObjectToString(value, p->version);

if (dump == NULL) {

p->error = WFERR_UNMARSHALLABLE;

Py_DECREF(pairs);

return;

}

PyObject *pair = PyTuple_Pack(2, dump, value);

Py_DECREF(dump);

if (pair == NULL) {

p->error = WFERR_NOMEMORY;

Py_DECREF(pairs);

return;

}

PyList_SET_ITEM(pairs, i++, pair);

}

assert(i == n);

if (PyList_Sort(pairs)) {

p->error = WFERR_NOMEMORY;

Py_DECREF(pairs);

return;

}

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

PyObject *pair = PyList_GET_ITEM(pairs, i);

value = PyTuple_GET_ITEM(pair, 1);

w_object(value, p);

}

Py_DECREF(pairs);

}

else if (PyCode_Check(v)) {

PyCodeObject *co = (PyCodeObject *)v;

PyObject *co_code = _PyCode_GetCode(co);

if (co_code == NULL) {

p->error = WFERR_NOMEMORY;

return;

}

W_TYPE(TYPE_CODE, p);

w_long(co->co_argcount, p);

w_long(co->co_posonlyargcount, p);

w_long(co->co_kwonlyargcount, p);

w_long(co->co_stacksize, p);

w_long(co->co_flags, p);

w_object(co_code, p);

w_object(co->co_consts, p);

w_object(co->co_names, p);

w_object(co->co_localsplusnames, p);

w_object(co->co_localspluskinds, p);

w_object(co->co_filename, p);

w_object(co->co_name, p);

w_object(co->co_qualname, p);

w_long(co->co_firstlineno, p);

w_object(co->co_linetable, p);

w_object(co->co_exceptiontable, p);

Py_DECREF(co_code);

}

else if (PyObject_CheckBuffer(v)) {

/* Write unknown bytes-like objects as a bytes object */

Py_buffer view;

if (PyObject_GetBuffer(v, &view, PyBUF_SIMPLE) != 0) {

w_byte(TYPE_UNKNOWN, p);

p->depth--;

p->error = WFERR_UNMARSHALLABLE;

return;

}

W_TYPE(TYPE_STRING, p);

w_pstring(view.buf, view.len, p);

PyBuffer_Release(&view);

}

else {

W_TYPE(TYPE_UNKNOWN, p);

p->error = WFERR_UNMARSHALLABLE;

}

static void

w_decref_entry(void *key)

{

PyObject *entry_key = (PyObject *)key;

Py_XDECREF(entry_key);

}

static int

w_init_refs(WFILE *wf, int version)

{

if (version >= 3) {

wf->hashtable = _Py_hashtable_new_full(_Py_hashtable_hash_ptr,

_Py_hashtable_compare_direct,

w_decref_entry, NULL, NULL);

if (wf->hashtable == NULL) {

PyErr_NoMemory();

return -1;

}

return 0;

}

static void

w_clear_refs(WFILE *wf)

{

if (wf->hashtable != NULL) {

_Py_hashtable_destroy(wf->hashtable);

}

/* version currently has no effect for writing ints. */

void

PyMarshal_WriteLongToFile(long x, FILE *fp, int version)

{

char buf[4];

WFILE wf;

memset(&wf, 0, sizeof(wf));

wf.fp = fp;

wf.ptr = wf.buf = buf;

wf.end = wf.ptr + sizeof(buf);

wf.error = WFERR_OK;

wf.version = version;

w_long(x, &wf);

w_flush(&wf);

}

void

PyMarshal_WriteObjectToFile(PyObject *x, FILE *fp, int version)

{

char buf[BUFSIZ];

WFILE wf;

if (PySys_Audit("marshal.dumps", "Oi", x, version) < 0) {

return; /* caller must check PyErr_Occurred() */

}

memset(&wf, 0, sizeof(wf));

wf.fp = fp;

wf.ptr = wf.buf = buf;

wf.end = wf.ptr + sizeof(buf);

wf.error = WFERR_OK;

wf.version = version;

if (w_init_refs(&wf, version)) {

return; /* caller must check PyErr_Occurred() */

}

w_object(x, &wf);

w_clear_refs(&wf);

w_flush(&wf);

}

typedef struct {

FILE *fp;

int depth;

PyObject *readable; /* Stream-like object being read from */

const char *ptr;

const char *end;

char *buf;

Py_ssize_t buf_size;

PyObject *refs; /* a list */

} RFILE;

static const char *

r_string(Py_ssize_t n, RFILE *p)

{

Py_ssize_t read = -1;

if (p->ptr != NULL) {

/* Fast path for loads() */

const char *res = p->ptr;

Py_ssize_t left = p->end - p->ptr;

if (left < n) {

PyErr_SetString(PyExc_EOFError,

"marshal data too short");

return NULL;

}

p->ptr += n;

return res;

}

if (p->buf == NULL) {

p->buf = PyMem_Malloc(n);

if (p->buf == NULL) {

PyErr_NoMemory();

return NULL;

}

p->buf_size = n;

}

else if (p->buf_size < n) {

char *tmp = PyMem_Realloc(p->buf, n);

if (tmp == NULL) {

PyErr_NoMemory();

return NULL;

}

p->buf = tmp;

p->buf_size = n;

}

if (!p->readable) {

assert(p->fp != NULL);

read = fread(p->buf, 1, n, p->fp);

}

else {

PyObject *res, *mview;

Py_buffer buf;

if (PyBuffer_FillInfo(&buf, NULL, p->buf, n, 0, PyBUF_CONTIG) == -1)

return NULL;

mview = PyMemoryView_FromBuffer(&buf);

if (mview == NULL)

return NULL;

res = _PyObject_CallMethod(p->readable, &_Py_ID(readinto), "N", mview);

if (res != NULL) {

read = PyNumber_AsSsize_t(res, PyExc_ValueError);

Py_DECREF(res);

}

if (read != n) {

if (!PyErr_Occurred()) {

if (read > n)

PyErr_Format(PyExc_ValueError,

"read() returned too much data: "

"%zd bytes requested, %zd returned",

n, read);

else

PyErr_SetString(PyExc_EOFError,

"EOF read where not expected");

}

return NULL;

}

return p->buf;

}

static int

r_byte(RFILE *p)

{

int c = EOF;

if (p->ptr != NULL) {

if (p->ptr < p->end)

c = (unsigned char) *p->ptr++;

return c;

}

if (!p->readable) {

assert(p->fp);

c = getc(p->fp);

}

else {

const char *ptr = r_string(1, p);

if (ptr != NULL)

c = *(const unsigned char *) ptr;

}

return c;

}

static int

r_short(RFILE *p)

{

short x = -1;

const unsigned char *buffer;

buffer = (const unsigned char *) r_string(2, p);

if (buffer != NULL) {

x = buffer[0];

x |= buffer[1] << 8;

/* Sign-extension, in case short greater than 16 bits */

x |= -(x & 0x8000);

}

return x;

}

static long

r_long(RFILE *p)

{

long x = -1;

const unsigned char *buffer;

buffer = (const unsigned char *) r_string(4, p);

if (buffer != NULL) {

x = buffer[0];

x |= (long)buffer[1] << 8;

x |= (long)buffer[2] << 16;

x |= (long)buffer[3] << 24;

#if SIZEOF_LONG > 4

/* Sign extension for 64-bit machines */

x |= -(x & 0x80000000L);

#endif

}

return x;

}

/* r_long64 deals with the TYPE_INT64 code. */

static PyObject *

r_long64(RFILE *p)

{

const unsigned char *buffer = (const unsigned char *) r_string(8, p);

if (buffer == NULL) {

return NULL;

}

return _PyLong_FromByteArray(buffer, 8,

1 /* little endian */,

1 /* signed */);

}

static PyObject *

r_PyLong(RFILE *p)

{

PyLongObject *ob;

long n, size, i;

int j, md, shorts_in_top_digit;

digit d;

n = r_long(p);

if (PyErr_Occurred())

return NULL;

if (n == 0)

return (PyObject *)_PyLong_New(0);

if (n < -SIZE32_MAX || n > SIZE32_MAX) {

PyErr_SetString(PyExc_ValueError,

"bad marshal data (long size out of range)");

return NULL;

}

size = 1 + (Py_ABS(n) - 1) / PyLong_MARSHAL_RATIO;

shorts_in_top_digit = 1 + (Py_ABS(n) - 1) % PyLong_MARSHAL_RATIO;

ob = _PyLong_New(size);

if (ob == NULL)

return NULL;

Py_SET_SIZE(ob, n > 0 ? size : -size);

for (i = 0; i < size-1; i++) {

d = 0;

for (j=0; j < PyLong_MARSHAL_RATIO; j++) {

md = r_short(p);

if (PyErr_Occurred()) {

Py_DECREF(ob);

return NULL;

}

if (md < 0 || md > PyLong_MARSHAL_BASE)

goto bad_digit;

d += (digit)md << j*PyLong_MARSHAL_SHIFT;

}

ob->ob_digit[i] = d;

}

d = 0;

for (j=0; j < shorts_in_top_digit; j++) {

md = r_short(p);

if (PyErr_Occurred()) {

Py_DECREF(ob);

return NULL;

}

if (md < 0 || md > PyLong_MARSHAL_BASE)

goto bad_digit;

/* topmost marshal digit should be nonzero */

if (md == 0 && j == shorts_in_top_digit - 1) {

Py_DECREF(ob);

PyErr_SetString(PyExc_ValueError,

"bad marshal data (unnormalized long data)");

return NULL;

}

d += (digit)md << j*PyLong_MARSHAL_SHIFT;

}

if (PyErr_Occurred()) {

Py_DECREF(ob);

return NULL;

}

/* top digit should be nonzero, else the resulting PyLong won't be

normalized */

ob->ob_digit[size-1] = d;

return (PyObject *)ob;

bad_digit:

Py_DECREF(ob);

PyErr_SetString(PyExc_ValueError,

"bad marshal data (digit out of range in long)");

return NULL;

}

static double

r_float_bin(RFILE *p)

{

const char *buf = r_string(8, p);

if (buf == NULL)

return -1;

return PyFloat_Unpack8(buf, 1);

}

/* Issue #33720: Disable inlining for reducing the C stack consumption

on PGO builds. */

Py_NO_INLINE static double

r_float_str(RFILE *p)

{

int n;

char buf[256];

const char *ptr;

n = r_byte(p);

if (n == EOF) {

PyErr_SetString(PyExc_EOFError,

"EOF read where object expected");

return -1;

}

ptr = r_string(n, p);

if (ptr == NULL) {

return -1;

}

memcpy(buf, ptr, n);

buf[n] = '\0';

return PyOS_string_to_double(buf, NULL, NULL);

}

/* allocate the reflist index for a new object. Return -1 on failure */

static Py_ssize_t

r_ref_reserve(int flag, RFILE *p)

{

if (flag) { /* currently only FLAG_REF is defined */

Py_ssize_t idx = PyList_GET_SIZE(p->refs);

if (idx >= 0x7ffffffe) {

PyErr_SetString(PyExc_ValueError, "bad marshal data (index list too large)");

return -1;

}

if (PyList_Append(p->refs, Py_None) < 0)

return -1;

return idx;

} else

return 0;

}

/* insert the new object 'o' to the reflist at previously

* allocated index 'idx'.

* 'o' can be NULL, in which case nothing is done.

* if 'o' was non-NULL, and the function succeeds, 'o' is returned.

* if 'o' was non-NULL, and the function fails, 'o' is released and

* NULL returned. This simplifies error checking at the call site since

* a single test for NULL for the function result is enough.

static PyObject *

r_ref_insert(PyObject *o, Py_ssize_t idx, int flag, RFILE *p)

{

if (o != NULL && flag) { /* currently only FLAG_REF is defined */

PyObject *tmp = PyList_GET_ITEM(p->refs, idx);

Py_INCREF(o);

PyList_SET_ITEM(p->refs, idx, o);

Py_DECREF(tmp);

}

return o;

}

/* combination of both above, used when an object can be

* created whenever it is seen in the file, as opposed to

* after having loaded its sub-objects.

static PyObject *

r_ref(PyObject *o, int flag, RFILE *p)

{

assert(flag & FLAG_REF);

if (o == NULL)

return NULL;

if (PyList_Append(p->refs, o) < 0) {

Py_DECREF(o); /* release the new object */

return NULL;

}

return o;

}

static PyObject *

r_object(RFILE *p)

{

/* NULL is a valid return value, it does not necessarily means that

an exception is set. */

PyObject *v, *v2;

Py_ssize_t idx = 0;

long i, n;

int type, code = r_byte(p);

int flag, is_interned = 0;

PyObject *retval = NULL;

if (code == EOF) {

PyErr_SetString(PyExc_EOFError,

"EOF read where object expected");

return NULL;

}

p->depth++;

if (p->depth > MAX_MARSHAL_STACK_DEPTH) {

p->depth--;

PyErr_SetString(PyExc_ValueError, "recursion limit exceeded");

View remainder of file in raw view

cpython/Python/marshal.c at 1388dd0a28046a15a7890f6d4082c87b98c65757 · python/cpython · GitHub

Uh oh!

Expand file tree

Breadcrumbs

marshal.c

Latest commit

History

Breadcrumbs

marshal.c

File metadata and controls