Hide keyboard shortcuts

Hot-keys on this page

r m x p   toggle line displays

j k   next/prev highlighted chunk

0   (zero) top of page

1   (one) first highlighted chunk

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

64

65

66

67

68

69

70

71

72

73

74

75

76

77

78

79

80

81

82

83

84

85

86

87

88

89

90

91

92

93

94

95

96

97

98

99

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

import types 

import weakref 

 

from .lock import allocate_lock 

from .error import CDefError, VerificationError, VerificationMissing 

 

# type qualifiers 

Q_CONST = 0x01 

Q_RESTRICT = 0x02 

Q_VOLATILE = 0x04 

 

def qualify(quals, replace_with): 

if quals & Q_CONST: 

replace_with = ' const ' + replace_with.lstrip() 

if quals & Q_VOLATILE: 

replace_with = ' volatile ' + replace_with.lstrip() 

if quals & Q_RESTRICT: 

# It seems that __restrict is supported by gcc and msvc. 

# If you hit some different compiler, add a #define in 

# _cffi_include.h for it (and in its copies, documented there) 

replace_with = ' __restrict ' + replace_with.lstrip() 

return replace_with 

 

 

class BaseTypeByIdentity(object): 

is_array_type = False 

is_raw_function = False 

 

def get_c_name(self, replace_with='', context='a C file', quals=0): 

result = self.c_name_with_marker 

assert result.count('&') == 1 

# some logic duplication with ffi.getctype()... :-( 

replace_with = replace_with.strip() 

if replace_with: 

if replace_with.startswith('*') and '&[' in result: 

replace_with = '(%s)' % replace_with 

elif not replace_with[0] in '[(': 

replace_with = ' ' + replace_with 

replace_with = qualify(quals, replace_with) 

result = result.replace('&', replace_with) 

if '$' in result: 

raise VerificationError( 

"cannot generate '%s' in %s: unknown type name" 

% (self._get_c_name(), context)) 

return result 

 

def _get_c_name(self): 

return self.c_name_with_marker.replace('&', '') 

 

def has_c_name(self): 

return '$' not in self._get_c_name() 

 

def is_integer_type(self): 

return False 

 

def get_cached_btype(self, ffi, finishlist, can_delay=False): 

try: 

BType = ffi._cached_btypes[self] 

except KeyError: 

BType = self.build_backend_type(ffi, finishlist) 

BType2 = ffi._cached_btypes.setdefault(self, BType) 

assert BType2 is BType 

return BType 

 

def __repr__(self): 

return '<%s>' % (self._get_c_name(),) 

 

def _get_items(self): 

return [(name, getattr(self, name)) for name in self._attrs_] 

 

 

class BaseType(BaseTypeByIdentity): 

 

def __eq__(self, other): 

return (self.__class__ == other.__class__ and 

self._get_items() == other._get_items()) 

 

def __ne__(self, other): 

return not self == other 

 

def __hash__(self): 

return hash((self.__class__, tuple(self._get_items()))) 

 

 

class VoidType(BaseType): 

_attrs_ = () 

 

def __init__(self): 

self.c_name_with_marker = 'void&' 

 

def build_backend_type(self, ffi, finishlist): 

return global_cache(self, ffi, 'new_void_type') 

 

void_type = VoidType() 

 

 

class BasePrimitiveType(BaseType): 

def is_complex_type(self): 

return False 

 

 

class PrimitiveType(BasePrimitiveType): 

_attrs_ = ('name',) 

 

ALL_PRIMITIVE_TYPES = { 

'char': 'c', 

'short': 'i', 

'int': 'i', 

'long': 'i', 

'long long': 'i', 

'signed char': 'i', 

'unsigned char': 'i', 

'unsigned short': 'i', 

'unsigned int': 'i', 

'unsigned long': 'i', 

'unsigned long long': 'i', 

'float': 'f', 

'double': 'f', 

'long double': 'f', 

'float _Complex': 'j', 

'double _Complex': 'j', 

'_Bool': 'i', 

# the following types are not primitive in the C sense 

'wchar_t': 'c', 

'char16_t': 'c', 

'char32_t': 'c', 

'int8_t': 'i', 

'uint8_t': 'i', 

'int16_t': 'i', 

'uint16_t': 'i', 

'int32_t': 'i', 

'uint32_t': 'i', 

'int64_t': 'i', 

'uint64_t': 'i', 

'int_least8_t': 'i', 

'uint_least8_t': 'i', 

'int_least16_t': 'i', 

'uint_least16_t': 'i', 

'int_least32_t': 'i', 

'uint_least32_t': 'i', 

'int_least64_t': 'i', 

'uint_least64_t': 'i', 

'int_fast8_t': 'i', 

'uint_fast8_t': 'i', 

'int_fast16_t': 'i', 

'uint_fast16_t': 'i', 

'int_fast32_t': 'i', 

'uint_fast32_t': 'i', 

'int_fast64_t': 'i', 

'uint_fast64_t': 'i', 

'intptr_t': 'i', 

'uintptr_t': 'i', 

'intmax_t': 'i', 

'uintmax_t': 'i', 

'ptrdiff_t': 'i', 

'size_t': 'i', 

'ssize_t': 'i', 

} 

 

def __init__(self, name): 

assert name in self.ALL_PRIMITIVE_TYPES 

self.name = name 

self.c_name_with_marker = name + '&' 

 

def is_char_type(self): 

return self.ALL_PRIMITIVE_TYPES[self.name] == 'c' 

def is_integer_type(self): 

return self.ALL_PRIMITIVE_TYPES[self.name] == 'i' 

def is_float_type(self): 

return self.ALL_PRIMITIVE_TYPES[self.name] == 'f' 

def is_complex_type(self): 

return self.ALL_PRIMITIVE_TYPES[self.name] == 'j' 

 

def build_backend_type(self, ffi, finishlist): 

return global_cache(self, ffi, 'new_primitive_type', self.name) 

 

 

class UnknownIntegerType(BasePrimitiveType): 

_attrs_ = ('name',) 

 

def __init__(self, name): 

self.name = name 

self.c_name_with_marker = name + '&' 

 

def is_integer_type(self): 

return True 

 

def build_backend_type(self, ffi, finishlist): 

raise NotImplementedError("integer type '%s' can only be used after " 

"compilation" % self.name) 

 

class UnknownFloatType(BasePrimitiveType): 

_attrs_ = ('name', ) 

 

def __init__(self, name): 

self.name = name 

self.c_name_with_marker = name + '&' 

 

def build_backend_type(self, ffi, finishlist): 

raise NotImplementedError("float type '%s' can only be used after " 

"compilation" % self.name) 

 

 

class BaseFunctionType(BaseType): 

_attrs_ = ('args', 'result', 'ellipsis', 'abi') 

 

def __init__(self, args, result, ellipsis, abi=None): 

self.args = args 

self.result = result 

self.ellipsis = ellipsis 

self.abi = abi 

# 

reprargs = [arg._get_c_name() for arg in self.args] 

if self.ellipsis: 

reprargs.append('...') 

reprargs = reprargs or ['void'] 

replace_with = self._base_pattern % (', '.join(reprargs),) 

if abi is not None: 

replace_with = replace_with[:1] + abi + ' ' + replace_with[1:] 

self.c_name_with_marker = ( 

self.result.c_name_with_marker.replace('&', replace_with)) 

 

 

class RawFunctionType(BaseFunctionType): 

# Corresponds to a C type like 'int(int)', which is the C type of 

# a function, but not a pointer-to-function. The backend has no 

# notion of such a type; it's used temporarily by parsing. 

_base_pattern = '(&)(%s)' 

is_raw_function = True 

 

def build_backend_type(self, ffi, finishlist): 

raise CDefError("cannot render the type %r: it is a function " 

"type, not a pointer-to-function type" % (self,)) 

 

def as_function_pointer(self): 

return FunctionPtrType(self.args, self.result, self.ellipsis, self.abi) 

 

 

class FunctionPtrType(BaseFunctionType): 

_base_pattern = '(*&)(%s)' 

 

def build_backend_type(self, ffi, finishlist): 

result = self.result.get_cached_btype(ffi, finishlist) 

args = [] 

for tp in self.args: 

args.append(tp.get_cached_btype(ffi, finishlist)) 

abi_args = () 

if self.abi == "__stdcall": 

if not self.ellipsis: # __stdcall ignored for variadic funcs 

try: 

abi_args = (ffi._backend.FFI_STDCALL,) 

except AttributeError: 

pass 

return global_cache(self, ffi, 'new_function_type', 

tuple(args), result, self.ellipsis, *abi_args) 

 

def as_raw_function(self): 

return RawFunctionType(self.args, self.result, self.ellipsis, self.abi) 

 

 

class PointerType(BaseType): 

_attrs_ = ('totype', 'quals') 

 

def __init__(self, totype, quals=0): 

self.totype = totype 

self.quals = quals 

extra = qualify(quals, " *&") 

if totype.is_array_type: 

extra = "(%s)" % (extra.lstrip(),) 

self.c_name_with_marker = totype.c_name_with_marker.replace('&', extra) 

 

def build_backend_type(self, ffi, finishlist): 

BItem = self.totype.get_cached_btype(ffi, finishlist, can_delay=True) 

return global_cache(self, ffi, 'new_pointer_type', BItem) 

 

voidp_type = PointerType(void_type) 

 

def ConstPointerType(totype): 

return PointerType(totype, Q_CONST) 

 

const_voidp_type = ConstPointerType(void_type) 

 

 

class NamedPointerType(PointerType): 

_attrs_ = ('totype', 'name') 

 

def __init__(self, totype, name, quals=0): 

PointerType.__init__(self, totype, quals) 

self.name = name 

self.c_name_with_marker = name + '&' 

 

 

class ArrayType(BaseType): 

_attrs_ = ('item', 'length') 

is_array_type = True 

 

def __init__(self, item, length): 

self.item = item 

self.length = length 

# 

if length is None: 

brackets = '&[]' 

elif length == '...': 

brackets = '&[/*...*/]' 

else: 

brackets = '&[%s]' % length 

self.c_name_with_marker = ( 

self.item.c_name_with_marker.replace('&', brackets)) 

 

def resolve_length(self, newlength): 

return ArrayType(self.item, newlength) 

 

def build_backend_type(self, ffi, finishlist): 

if self.length == '...': 

raise CDefError("cannot render the type %r: unknown length" % 

(self,)) 

self.item.get_cached_btype(ffi, finishlist) # force the item BType 

BPtrItem = PointerType(self.item).get_cached_btype(ffi, finishlist) 

return global_cache(self, ffi, 'new_array_type', BPtrItem, self.length) 

 

char_array_type = ArrayType(PrimitiveType('char'), None) 

 

 

class StructOrUnionOrEnum(BaseTypeByIdentity): 

_attrs_ = ('name',) 

forcename = None 

 

def build_c_name_with_marker(self): 

name = self.forcename or '%s %s' % (self.kind, self.name) 

self.c_name_with_marker = name + '&' 

 

def force_the_name(self, forcename): 

self.forcename = forcename 

self.build_c_name_with_marker() 

 

def get_official_name(self): 

assert self.c_name_with_marker.endswith('&') 

return self.c_name_with_marker[:-1] 

 

 

class StructOrUnion(StructOrUnionOrEnum): 

fixedlayout = None 

completed = 0 

partial = False 

packed = 0 

 

def __init__(self, name, fldnames, fldtypes, fldbitsize, fldquals=None): 

self.name = name 

self.fldnames = fldnames 

self.fldtypes = fldtypes 

self.fldbitsize = fldbitsize 

self.fldquals = fldquals 

self.build_c_name_with_marker() 

 

def anonymous_struct_fields(self): 

if self.fldtypes is not None: 

for name, type in zip(self.fldnames, self.fldtypes): 

if name == '' and isinstance(type, StructOrUnion): 

yield type 

 

def enumfields(self, expand_anonymous_struct_union=True): 

fldquals = self.fldquals 

if fldquals is None: 

fldquals = (0,) * len(self.fldnames) 

for name, type, bitsize, quals in zip(self.fldnames, self.fldtypes, 

self.fldbitsize, fldquals): 

if (name == '' and isinstance(type, StructOrUnion) 

and expand_anonymous_struct_union): 

# nested anonymous struct/union 

for result in type.enumfields(): 

yield result 

else: 

yield (name, type, bitsize, quals) 

 

def force_flatten(self): 

# force the struct or union to have a declaration that lists 

# directly all fields returned by enumfields(), flattening 

# nested anonymous structs/unions. 

names = [] 

types = [] 

bitsizes = [] 

fldquals = [] 

for name, type, bitsize, quals in self.enumfields(): 

names.append(name) 

types.append(type) 

bitsizes.append(bitsize) 

fldquals.append(quals) 

self.fldnames = tuple(names) 

self.fldtypes = tuple(types) 

self.fldbitsize = tuple(bitsizes) 

self.fldquals = tuple(fldquals) 

 

def get_cached_btype(self, ffi, finishlist, can_delay=False): 

BType = StructOrUnionOrEnum.get_cached_btype(self, ffi, finishlist, 

can_delay) 

if not can_delay: 

self.finish_backend_type(ffi, finishlist) 

return BType 

 

def finish_backend_type(self, ffi, finishlist): 

if self.completed: 

if self.completed != 2: 

raise NotImplementedError("recursive structure declaration " 

"for '%s'" % (self.name,)) 

return 

BType = ffi._cached_btypes[self] 

# 

self.completed = 1 

# 

if self.fldtypes is None: 

pass # not completing it: it's an opaque struct 

# 

elif self.fixedlayout is None: 

fldtypes = [tp.get_cached_btype(ffi, finishlist) 

for tp in self.fldtypes] 

lst = list(zip(self.fldnames, fldtypes, self.fldbitsize)) 

extra_flags = () 

if self.packed: 

if self.packed == 1: 

extra_flags = (8,) # SF_PACKED 

else: 

extra_flags = (0, self.packed) 

ffi._backend.complete_struct_or_union(BType, lst, self, 

-1, -1, *extra_flags) 

# 

else: 

fldtypes = [] 

fieldofs, fieldsize, totalsize, totalalignment = self.fixedlayout 

for i in range(len(self.fldnames)): 

fsize = fieldsize[i] 

ftype = self.fldtypes[i] 

# 

if isinstance(ftype, ArrayType) and ftype.length == '...': 

# fix the length to match the total size 

BItemType = ftype.item.get_cached_btype(ffi, finishlist) 

nlen, nrest = divmod(fsize, ffi.sizeof(BItemType)) 

if nrest != 0: 

self._verification_error( 

"field '%s.%s' has a bogus size?" % ( 

self.name, self.fldnames[i] or '{}')) 

ftype = ftype.resolve_length(nlen) 

self.fldtypes = (self.fldtypes[:i] + (ftype,) + 

self.fldtypes[i+1:]) 

# 

BFieldType = ftype.get_cached_btype(ffi, finishlist) 

if isinstance(ftype, ArrayType) and ftype.length is None: 

assert fsize == 0 

else: 

bitemsize = ffi.sizeof(BFieldType) 

if bitemsize != fsize: 

self._verification_error( 

"field '%s.%s' is declared as %d bytes, but is " 

"really %d bytes" % (self.name, 

self.fldnames[i] or '{}', 

bitemsize, fsize)) 

fldtypes.append(BFieldType) 

# 

lst = list(zip(self.fldnames, fldtypes, self.fldbitsize, fieldofs)) 

ffi._backend.complete_struct_or_union(BType, lst, self, 

totalsize, totalalignment) 

self.completed = 2 

 

def _verification_error(self, msg): 

raise VerificationError(msg) 

 

def check_not_partial(self): 

if self.partial and self.fixedlayout is None: 

raise VerificationMissing(self._get_c_name()) 

 

def build_backend_type(self, ffi, finishlist): 

self.check_not_partial() 

finishlist.append(self) 

# 

return global_cache(self, ffi, 'new_%s_type' % self.kind, 

self.get_official_name(), key=self) 

 

 

class StructType(StructOrUnion): 

kind = 'struct' 

 

 

class UnionType(StructOrUnion): 

kind = 'union' 

 

 

class EnumType(StructOrUnionOrEnum): 

kind = 'enum' 

partial = False 

partial_resolved = False 

 

def __init__(self, name, enumerators, enumvalues, baseinttype=None): 

self.name = name 

self.enumerators = enumerators 

self.enumvalues = enumvalues 

self.baseinttype = baseinttype 

self.build_c_name_with_marker() 

 

def force_the_name(self, forcename): 

StructOrUnionOrEnum.force_the_name(self, forcename) 

if self.forcename is None: 

name = self.get_official_name() 

self.forcename = '$' + name.replace(' ', '_') 

 

def check_not_partial(self): 

if self.partial and not self.partial_resolved: 

raise VerificationMissing(self._get_c_name()) 

 

def build_backend_type(self, ffi, finishlist): 

self.check_not_partial() 

base_btype = self.build_baseinttype(ffi, finishlist) 

return global_cache(self, ffi, 'new_enum_type', 

self.get_official_name(), 

self.enumerators, self.enumvalues, 

base_btype, key=self) 

 

def build_baseinttype(self, ffi, finishlist): 

if self.baseinttype is not None: 

return self.baseinttype.get_cached_btype(ffi, finishlist) 

# 

if self.enumvalues: 

smallest_value = min(self.enumvalues) 

largest_value = max(self.enumvalues) 

else: 

import warnings 

try: 

# XXX! The goal is to ensure that the warnings.warn() 

# will not suppress the warning. We want to get it 

# several times if we reach this point several times. 

__warningregistry__.clear() 

except NameError: 

pass 

warnings.warn("%r has no values explicitly defined; " 

"guessing that it is equivalent to 'unsigned int'" 

% self._get_c_name()) 

smallest_value = largest_value = 0 

if smallest_value < 0: # needs a signed type 

sign = 1 

candidate1 = PrimitiveType("int") 

candidate2 = PrimitiveType("long") 

else: 

sign = 0 

candidate1 = PrimitiveType("unsigned int") 

candidate2 = PrimitiveType("unsigned long") 

btype1 = candidate1.get_cached_btype(ffi, finishlist) 

btype2 = candidate2.get_cached_btype(ffi, finishlist) 

size1 = ffi.sizeof(btype1) 

size2 = ffi.sizeof(btype2) 

if (smallest_value >= ((-1) << (8*size1-1)) and 

largest_value < (1 << (8*size1-sign))): 

return btype1 

if (smallest_value >= ((-1) << (8*size2-1)) and 

largest_value < (1 << (8*size2-sign))): 

return btype2 

raise CDefError("%s values don't all fit into either 'long' " 

"or 'unsigned long'" % self._get_c_name()) 

 

def unknown_type(name, structname=None): 

if structname is None: 

structname = '$%s' % name 

tp = StructType(structname, None, None, None) 

tp.force_the_name(name) 

tp.origin = "unknown_type" 

return tp 

 

def unknown_ptr_type(name, structname=None): 

if structname is None: 

structname = '$$%s' % name 

tp = StructType(structname, None, None, None) 

return NamedPointerType(tp, name) 

 

 

global_lock = allocate_lock() 

_typecache_cffi_backend = weakref.WeakValueDictionary() 

 

def get_typecache(backend): 

# returns _typecache_cffi_backend if backend is the _cffi_backend 

# module, or type(backend).__typecache if backend is an instance of 

# CTypesBackend (or some FakeBackend class during tests) 

if isinstance(backend, types.ModuleType): 

return _typecache_cffi_backend 

with global_lock: 

if not hasattr(type(backend), '__typecache'): 

type(backend).__typecache = weakref.WeakValueDictionary() 

return type(backend).__typecache 

 

def global_cache(srctype, ffi, funcname, *args, **kwds): 

key = kwds.pop('key', (funcname, args)) 

assert not kwds 

try: 

return ffi._typecache[key] 

except KeyError: 

pass 

try: 

res = getattr(ffi._backend, funcname)(*args) 

except NotImplementedError as e: 

raise NotImplementedError("%s: %r: %s" % (funcname, srctype, e)) 

# note that setdefault() on WeakValueDictionary is not atomic 

# and contains a rare bug (http://bugs.python.org/issue19542); 

# we have to use a lock and do it ourselves 

cache = ffi._typecache 

with global_lock: 

res1 = cache.get(key) 

if res1 is None: 

cache[key] = res 

return res 

else: 

return res1 

 

def pointer_cache(ffi, BType): 

return global_cache('?', ffi, 'new_pointer_type', BType) 

 

def attach_exception_info(e, name): 

if e.args and type(e.args[0]) is str: 

e.args = ('%s: %s' % (name, e.args[0]),) + e.args[1:]