{{ message }}
forked from python/cpython
-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathtypeobject.c
More file actions
8284 lines (7339 loc) · 254 KB
/
Copy pathtypeobject.c
File metadata and controls
8284 lines (7339 loc) · 254 KB
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
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
/* Type object implementation */
#include "Python.h"
#include "pycore_call.h"
#include "pycore_initconfig.h"
#include "pycore_object.h"
#include "pycore_pyerrors.h"
#include "pycore_pystate.h" // _PyThreadState_GET()
#include "frameobject.h"
#include "structmember.h" // PyMemberDef
#include <ctype.h>
/*[clinic input]
class type "PyTypeObject *" "&PyType_Type"
class object "PyObject *" "&PyBaseObject_Type"
[clinic start generated code]*/
/*[clinic end generated code: output=da39a3ee5e6b4b0d input=4b94608d231c434b]*/
#include "clinic/typeobject.c.h"
#define MCACHE
#ifdef MCACHE
/* Support type attribute cache */
/* The cache can keep references to the names alive for longer than
they normally would. This is why the maximum size is limited to
MCACHE_MAX_ATTR_SIZE, since it might be a problem if very large
strings are used as attribute names. */
#define MCACHE_MAX_ATTR_SIZE 100
#define MCACHE_SIZE_EXP 12
#define MCACHE_HASH(version, name_hash) \
(((unsigned int)(version) ^ (unsigned int)(name_hash)) \
& ((1 << MCACHE_SIZE_EXP) - 1))
#define MCACHE_HASH_METHOD(type, name) \
MCACHE_HASH((type)->tp_version_tag, \
((PyASCIIObject *)(name))->hash)
#define MCACHE_CACHEABLE_NAME(name) \
PyUnicode_CheckExact(name) && \
PyUnicode_IS_READY(name) && \
PyUnicode_GET_LENGTH(name) <= MCACHE_MAX_ATTR_SIZE
struct method_cache_entry {
unsigned int version;
PyObject *name; /* reference to exactly a str or None */
PyObject *value; /* borrowed */
};
static struct method_cache_entry method_cache[1 << MCACHE_SIZE_EXP];
static unsigned int next_version_tag = 0;
#endif
#define MCACHE_STATS 0
#if MCACHE_STATS
static size_t method_cache_hits = 0;
static size_t method_cache_misses = 0;
static size_t method_cache_collisions = 0;
#endif
#define INTERN_NAME_STRINGS
/* alphabetical order */
_Py_IDENTIFIER(__abstractmethods__);
_Py_IDENTIFIER(__class__);
_Py_IDENTIFIER(__class_getitem__);
_Py_IDENTIFIER(__delitem__);
_Py_IDENTIFIER(__dict__);
_Py_IDENTIFIER(__doc__);
_Py_IDENTIFIER(__getattribute__);
_Py_IDENTIFIER(__getitem__);
_Py_IDENTIFIER(__hash__);
_Py_IDENTIFIER(__init_subclass__);
_Py_IDENTIFIER(__len__);
_Py_IDENTIFIER(__module__);
_Py_IDENTIFIER(__name__);
_Py_IDENTIFIER(__new__);
_Py_IDENTIFIER(__set_name__);
_Py_IDENTIFIER(__setitem__);
_Py_IDENTIFIER(builtins);
_Py_IDENTIFIER(mro);
static PyObject *
slot_tp_new(PyTypeObject *type, PyObject *args, PyObject *kwds);
static void
clear_slotdefs(void);
static PyObject *
lookup_maybe_method(PyObject *self, _Py_Identifier *attrid, int *unbound);
static int
slot_tp_setattro(PyObject *self, PyObject *name, PyObject *value);
/*
* finds the beginning of the docstring's introspection signature.
* if present, returns a pointer pointing to the first '('.
* otherwise returns NULL.
*
* doesn't guarantee that the signature is valid, only that it
* has a valid prefix. (the signature must also pass skip_signature.)
*/
static const char *
find_signature(const char *name, const char *doc)
{
const char *dot;
size_t length;
if (!doc)
return NULL;
assert(name != NULL);
/* for dotted names like classes, only use the last component */
dot = strrchr(name, '.');
if (dot)
name = dot + 1;
length = strlen(name);
if (strncmp(doc, name, length))
return NULL;
doc += length;
if (*doc != '(')
return NULL;
return doc;
}
#define SIGNATURE_END_MARKER ")\n--\n\n"
#define SIGNATURE_END_MARKER_LENGTH 6
/*
* skips past the end of the docstring's introspection signature.
* (assumes doc starts with a valid signature prefix.)
*/
static const char *
skip_signature(const char *doc)
{
while (*doc) {
if ((*doc == *SIGNATURE_END_MARKER) &&
!strncmp(doc, SIGNATURE_END_MARKER, SIGNATURE_END_MARKER_LENGTH))
return doc + SIGNATURE_END_MARKER_LENGTH;
if ((*doc == '\n') && (doc[1] == '\n'))
return NULL;
doc++;
}
return NULL;
}
int
_PyType_CheckConsistency(PyTypeObject *type)
{
#define CHECK(expr) \
do { if (!(expr)) { _PyObject_ASSERT_FAILED_MSG((PyObject *)type, Py_STRINGIFY(expr)); } } while (0)
CHECK(!_PyObject_IsFreed((PyObject *)type));
if (!(type->tp_flags & Py_TPFLAGS_READY)) {
/* don't check static types before PyType_Ready() */
return 1;
}
CHECK(Py_REFCNT(type) >= 1);
CHECK(PyType_Check(type));
CHECK(!(type->tp_flags & Py_TPFLAGS_READYING));
CHECK(type->tp_dict != NULL);
return 1;
#undef CHECK
}
static const char *
_PyType_DocWithoutSignature(const char *name, const char *internal_doc)
{
const char *doc = find_signature(name, internal_doc);
if (doc) {
doc = skip_signature(doc);
if (doc)
return doc;
}
return internal_doc;
}
PyObject *
_PyType_GetDocFromInternalDoc(const char *name, const char *internal_doc)
{
const char *doc = _PyType_DocWithoutSignature(name, internal_doc);
if (!doc || *doc == '\0') {
Py_RETURN_NONE;
}
return PyUnicode_FromString(doc);
}
PyObject *
_PyType_GetTextSignatureFromInternalDoc(const char *name, const char *internal_doc)
{
const char *start = find_signature(name, internal_doc);
const char *end;
if (start)
end = skip_signature(start);
else
end = NULL;
if (!end) {
Py_RETURN_NONE;
}
/* back "end" up until it points just past the final ')' */
end -= SIGNATURE_END_MARKER_LENGTH - 1;
assert((end - start) >= 2); /* should be "()" at least */
assert(end[-1] == ')');
assert(end[0] == '\n');
return PyUnicode_FromStringAndSize(start, end - start);
}
unsigned int
PyType_ClearCache(void)
{
#ifdef MCACHE
Py_ssize_t i;
unsigned int cur_version_tag = next_version_tag - 1;
#if MCACHE_STATS
size_t total = method_cache_hits + method_cache_collisions + method_cache_misses;
fprintf(stderr, "-- Method cache hits = %zd (%d%%)\n",
method_cache_hits, (int) (100.0 * method_cache_hits / total));
fprintf(stderr, "-- Method cache true misses = %zd (%d%%)\n",
method_cache_misses, (int) (100.0 * method_cache_misses / total));
fprintf(stderr, "-- Method cache collisions = %zd (%d%%)\n",
method_cache_collisions, (int) (100.0 * method_cache_collisions / total));
fprintf(stderr, "-- Method cache size = %zd KiB\n",
sizeof(method_cache) / 1024);
#endif
for (i = 0; i < (1 << MCACHE_SIZE_EXP); i++) {
method_cache[i].version = 0;
Py_CLEAR(method_cache[i].name);
method_cache[i].value = NULL;
}
next_version_tag = 0;
/* mark all version tags as invalid */
PyType_Modified(&PyBaseObject_Type);
return cur_version_tag;
#else
return 0;
#endif
}
void
_PyType_Fini(void)
{
PyType_ClearCache();
clear_slotdefs();
}
void
PyType_Modified(PyTypeObject *type)
{
/* Invalidate any cached data for the specified type and all
subclasses. This function is called after the base
classes, mro, or attributes of the type are altered.
Invariants:
- Py_TPFLAGS_VALID_VERSION_TAG is never set if
Py_TPFLAGS_HAVE_VERSION_TAG is not set (in case of a
bizarre MRO, see type_mro_modified()).
- before Py_TPFLAGS_VALID_VERSION_TAG can be set on a type,
it must first be set on all super types.
This function clears the Py_TPFLAGS_VALID_VERSION_TAG of a
type (so it must first clear it on all subclasses). The
tp_version_tag value is meaningless unless this flag is set.
We don't assign new version tags eagerly, but only as
needed.
*/
PyObject *raw, *ref;
Py_ssize_t i;
if (!_PyType_HasFeature(type, Py_TPFLAGS_VALID_VERSION_TAG))
return;
raw = type->tp_subclasses;
if (raw != NULL) {
assert(PyDict_CheckExact(raw));
i = 0;
while (PyDict_Next(raw, &i, NULL, &ref)) {
assert(PyWeakref_CheckRef(ref));
ref = PyWeakref_GET_OBJECT(ref);
if (ref != Py_None) {
PyType_Modified((PyTypeObject *)ref);
}
}
}
type->tp_flags &= ~Py_TPFLAGS_VALID_VERSION_TAG;
}
static void
type_mro_modified(PyTypeObject *type, PyObject *bases) {
/*
Check that all base classes or elements of the MRO of type are
able to be cached. This function is called after the base
classes or mro of the type are altered.
Unset HAVE_VERSION_TAG and VALID_VERSION_TAG if the type
has a custom MRO that includes a type which is not officially
super type, or if the type implements its own mro() method.
Called from mro_internal, which will subsequently be called on
each subclass when their mro is recursively updated.
*/
Py_ssize_t i, n;
int custom = !Py_IS_TYPE(type, &PyType_Type);
int unbound;
PyObject *mro_meth = NULL;
PyObject *type_mro_meth = NULL;
if (!_PyType_HasFeature(type, Py_TPFLAGS_HAVE_VERSION_TAG))
return;
if (custom) {
mro_meth = lookup_maybe_method(
(PyObject *)type, &PyId_mro, &unbound);
if (mro_meth == NULL)
goto clear;
type_mro_meth = lookup_maybe_method(
(PyObject *)&PyType_Type, &PyId_mro, &unbound);
if (type_mro_meth == NULL)
goto clear;
if (mro_meth != type_mro_meth)
goto clear;
Py_XDECREF(mro_meth);
Py_XDECREF(type_mro_meth);
}
n = PyTuple_GET_SIZE(bases);
for (i = 0; i < n; i++) {
PyObject *b = PyTuple_GET_ITEM(bases, i);
PyTypeObject *cls;
assert(PyType_Check(b));
cls = (PyTypeObject *)b;
if (!_PyType_HasFeature(cls, Py_TPFLAGS_HAVE_VERSION_TAG) ||
!PyType_IsSubtype(type, cls)) {
goto clear;
}
}
return;
clear:
Py_XDECREF(mro_meth);
Py_XDECREF(type_mro_meth);
type->tp_flags &= ~(Py_TPFLAGS_HAVE_VERSION_TAG|
Py_TPFLAGS_VALID_VERSION_TAG);
}
#ifdef MCACHE
static int
assign_version_tag(PyTypeObject *type)
{
/* Ensure that the tp_version_tag is valid and set
Py_TPFLAGS_VALID_VERSION_TAG. To respect the invariant, this
must first be done on all super classes. Return 0 if this
cannot be done, 1 if Py_TPFLAGS_VALID_VERSION_TAG.
*/
Py_ssize_t i, n;
PyObject *bases;
if (_PyType_HasFeature(type, Py_TPFLAGS_VALID_VERSION_TAG))
return 1;
if (!_PyType_HasFeature(type, Py_TPFLAGS_HAVE_VERSION_TAG))
return 0;
if (!_PyType_HasFeature(type, Py_TPFLAGS_READY))
return 0;
type->tp_version_tag = next_version_tag++;
/* for stress-testing: next_version_tag &= 0xFF; */
if (type->tp_version_tag == 0) {
/* wrap-around or just starting Python - clear the whole
cache by filling names with references to Py_None.
Values are also set to NULL for added protection, as they
are borrowed reference */
for (i = 0; i < (1 << MCACHE_SIZE_EXP); i++) {
method_cache[i].value = NULL;
Py_INCREF(Py_None);
Py_XSETREF(method_cache[i].name, Py_None);
}
/* mark all version tags as invalid */
PyType_Modified(&PyBaseObject_Type);
return 1;
}
bases = type->tp_bases;
n = PyTuple_GET_SIZE(bases);
for (i = 0; i < n; i++) {
PyObject *b = PyTuple_GET_ITEM(bases, i);
assert(PyType_Check(b));
if (!assign_version_tag((PyTypeObject *)b))
return 0;
}
type->tp_flags |= Py_TPFLAGS_VALID_VERSION_TAG;
return 1;
}
#endif
static PyMemberDef type_members[] = {
{"__basicsize__", T_PYSSIZET, offsetof(PyTypeObject,tp_basicsize),READONLY},
{"__itemsize__", T_PYSSIZET, offsetof(PyTypeObject, tp_itemsize), READONLY},
{"__flags__", T_ULONG, offsetof(PyTypeObject, tp_flags), READONLY},
{"__weakrefoffset__", T_PYSSIZET,
offsetof(PyTypeObject, tp_weaklistoffset), READONLY},
{"__base__", T_OBJECT, offsetof(PyTypeObject, tp_base), READONLY},
{"__dictoffset__", T_PYSSIZET,
offsetof(PyTypeObject, tp_dictoffset), READONLY},
{"__mro__", T_OBJECT, offsetof(PyTypeObject, tp_mro), READONLY},
{0}
};
static int
check_set_special_type_attr(PyTypeObject *type, PyObject *value, const char *name)
{
if (!(type->tp_flags & Py_TPFLAGS_HEAPTYPE)) {
PyErr_Format(PyExc_TypeError,
"can't set %s.%s", type->tp_name, name);
return 0;
}
if (!value) {
PyErr_Format(PyExc_TypeError,
"can't delete %s.%s", type->tp_name, name);
return 0;
}
if (PySys_Audit("object.__setattr__", "OsO",
type, name, value) < 0) {
return 0;
}
return 1;
}
const char *
_PyType_Name(PyTypeObject *type)
{
assert(type->tp_name != NULL);
const char *s = strrchr(type->tp_name, '.');
if (s == NULL) {
s = type->tp_name;
}
else {
s++;
}
return s;
}
static PyObject *
type_name(PyTypeObject *type, void *context)
{
if (type->tp_flags & Py_TPFLAGS_HEAPTYPE) {
PyHeapTypeObject* et = (PyHeapTypeObject*)type;
Py_INCREF(et->ht_name);
return et->ht_name;
}
else {
return PyUnicode_FromString(_PyType_Name(type));
}
}
static PyObject *
type_qualname(PyTypeObject *type, void *context)
{
if (type->tp_flags & Py_TPFLAGS_HEAPTYPE) {
PyHeapTypeObject* et = (PyHeapTypeObject*)type;
Py_INCREF(et->ht_qualname);
return et->ht_qualname;
}
else {
return PyUnicode_FromString(_PyType_Name(type));
}
}
static int
type_set_name(PyTypeObject *type, PyObject *value, void *context)
{
const char *tp_name;
Py_ssize_t name_size;
if (!check_set_special_type_attr(type, value, "__name__"))
return -1;
if (!PyUnicode_Check(value)) {
PyErr_Format(PyExc_TypeError,
"can only assign string to %s.__name__, not '%s'",
type->tp_name, Py_TYPE(value)->tp_name);
return -1;
}
tp_name = PyUnicode_AsUTF8AndSize(value, &name_size);
if (tp_name == NULL)
return -1;
if (strlen(tp_name) != (size_t)name_size) {
PyErr_SetString(PyExc_ValueError,
"type name must not contain null characters");
return -1;
}
type->tp_name = tp_name;
Py_INCREF(value);
Py_SETREF(((PyHeapTypeObject*)type)->ht_name, value);
return 0;
}
static int
type_set_qualname(PyTypeObject *type, PyObject *value, void *context)
{
PyHeapTypeObject* et;
if (!check_set_special_type_attr(type, value, "__qualname__"))
return -1;
if (!PyUnicode_Check(value)) {
PyErr_Format(PyExc_TypeError,
"can only assign string to %s.__qualname__, not '%s'",
type->tp_name, Py_TYPE(value)->tp_name);
return -1;
}
et = (PyHeapTypeObject*)type;
Py_INCREF(value);
Py_SETREF(et->ht_qualname, value);
return 0;
}
static PyObject *
type_module(PyTypeObject *type, void *context)
{
PyObject *mod;
if (type->tp_flags & Py_TPFLAGS_HEAPTYPE) {
mod = _PyDict_GetItemIdWithError(type->tp_dict, &PyId___module__);
if (mod == NULL) {
if (!PyErr_Occurred()) {
PyErr_Format(PyExc_AttributeError, "__module__");
}
return NULL;
}
Py_INCREF(mod);
}
else {
const char *s = strrchr(type->tp_name, '.');
if (s != NULL) {
mod = PyUnicode_FromStringAndSize(
type->tp_name, (Py_ssize_t)(s - type->tp_name));
if (mod != NULL)
PyUnicode_InternInPlace(&mod);
}
else {
mod = _PyUnicode_FromId(&PyId_builtins);
Py_XINCREF(mod);
}
}
return mod;
}
static int
type_set_module(PyTypeObject *type, PyObject *value, void *context)
{
if (!check_set_special_type_attr(type, value, "__module__"))
return -1;
PyType_Modified(type);
return _PyDict_SetItemId(type->tp_dict, &PyId___module__, value);
}
static PyObject *
type_abstractmethods(PyTypeObject *type, void *context)
{
PyObject *mod = NULL;
/* type itself has an __abstractmethods__ descriptor (this). Don't return
that. */
if (type != &PyType_Type)
mod = _PyDict_GetItemIdWithError(type->tp_dict, &PyId___abstractmethods__);
if (!mod) {
if (!PyErr_Occurred()) {
PyObject *message = _PyUnicode_FromId(&PyId___abstractmethods__);
if (message)
PyErr_SetObject(PyExc_AttributeError, message);
}
return NULL;
}
Py_INCREF(mod);
return mod;
}
static int
type_set_abstractmethods(PyTypeObject *type, PyObject *value, void *context)
{
/* __abstractmethods__ should only be set once on a type, in
abc.ABCMeta.__new__, so this function doesn't do anything
special to update subclasses.
*/
int abstract, res;
if (value != NULL) {
abstract = PyObject_IsTrue(value);
if (abstract < 0)
return -1;
res = _PyDict_SetItemId(type->tp_dict, &PyId___abstractmethods__, value);
}
else {
abstract = 0;
res = _PyDict_DelItemId(type->tp_dict, &PyId___abstractmethods__);
if (res && PyErr_ExceptionMatches(PyExc_KeyError)) {
PyObject *message = _PyUnicode_FromId(&PyId___abstractmethods__);
if (message)
PyErr_SetObject(PyExc_AttributeError, message);
return -1;
}
}
if (res == 0) {
PyType_Modified(type);
if (abstract)
type->tp_flags |= Py_TPFLAGS_IS_ABSTRACT;
else
type->tp_flags &= ~Py_TPFLAGS_IS_ABSTRACT;
}
return res;
}
static PyObject *
type_get_bases(PyTypeObject *type, void *context)
{
Py_INCREF(type->tp_bases);
return type->tp_bases;
}
static PyTypeObject *best_base(PyObject *);
static int mro_internal(PyTypeObject *, PyObject **);
static int type_is_subtype_base_chain(PyTypeObject *, PyTypeObject *);
static int compatible_for_assignment(PyTypeObject *, PyTypeObject *, const char *);
static int add_subclass(PyTypeObject*, PyTypeObject*);
static int add_all_subclasses(PyTypeObject *type, PyObject *bases);
static void remove_subclass(PyTypeObject *, PyTypeObject *);
static void remove_all_subclasses(PyTypeObject *type, PyObject *bases);
static void update_all_slots(PyTypeObject *);
typedef int (*update_callback)(PyTypeObject *, void *);
static int update_subclasses(PyTypeObject *type, PyObject *name,
update_callback callback, void *data);
static int recurse_down_subclasses(PyTypeObject *type, PyObject *name,
update_callback callback, void *data);
static int
mro_hierarchy(PyTypeObject *type, PyObject *temp)
{
int res;
PyObject *new_mro, *old_mro;
PyObject *tuple;
PyObject *subclasses;
Py_ssize_t i, n;
res = mro_internal(type, &old_mro);
if (res <= 0)
/* error / reentrance */
return res;
new_mro = type->tp_mro;
if (old_mro != NULL)
tuple = PyTuple_Pack(3, type, new_mro, old_mro);
else
tuple = PyTuple_Pack(2, type, new_mro);
if (tuple != NULL)
res = PyList_Append(temp, tuple);
else
res = -1;
Py_XDECREF(tuple);
if (res < 0) {
type->tp_mro = old_mro;
Py_DECREF(new_mro);
return -1;
}
Py_XDECREF(old_mro);
/* Obtain a copy of subclasses list to iterate over.
Otherwise type->tp_subclasses might be altered
in the middle of the loop, for example, through a custom mro(),
by invoking type_set_bases on some subclass of the type
which in turn calls remove_subclass/add_subclass on this type.
Finally, this makes things simple avoiding the need to deal
with dictionary iterators and weak references.
*/
subclasses = type___subclasses___impl(type);
if (subclasses == NULL)
return -1;
n = PyList_GET_SIZE(subclasses);
for (i = 0; i < n; i++) {
PyTypeObject *subclass;
subclass = (PyTypeObject *)PyList_GET_ITEM(subclasses, i);
res = mro_hierarchy(subclass, temp);
if (res < 0)
break;
}
Py_DECREF(subclasses);
return res;
}
static int
type_set_bases(PyTypeObject *type, PyObject *new_bases, void *context)
{
int res = 0;
PyObject *temp;
PyObject *old_bases;
PyTypeObject *new_base, *old_base;
Py_ssize_t i;
if (!check_set_special_type_attr(type, new_bases, "__bases__"))
return -1;
if (!PyTuple_Check(new_bases)) {
PyErr_Format(PyExc_TypeError,
"can only assign tuple to %s.__bases__, not %s",
type->tp_name, Py_TYPE(new_bases)->tp_name);
return -1;
}
if (PyTuple_GET_SIZE(new_bases) == 0) {
PyErr_Format(PyExc_TypeError,
"can only assign non-empty tuple to %s.__bases__, not ()",
type->tp_name);
return -1;
}
for (i = 0; i < PyTuple_GET_SIZE(new_bases); i++) {
PyObject *ob;
PyTypeObject *base;
ob = PyTuple_GET_ITEM(new_bases, i);
if (!PyType_Check(ob)) {
PyErr_Format(PyExc_TypeError,
"%s.__bases__ must be tuple of classes, not '%s'",
type->tp_name, Py_TYPE(ob)->tp_name);
return -1;
}
base = (PyTypeObject*)ob;
if (PyType_IsSubtype(base, type) ||
/* In case of reentering here again through a custom mro()
the above check is not enough since it relies on
base->tp_mro which would gonna be updated inside
mro_internal only upon returning from the mro().
However, base->tp_base has already been assigned (see
below), which in turn may cause an inheritance cycle
through tp_base chain. And this is definitely
not what you want to ever happen. */
(base->tp_mro != NULL && type_is_subtype_base_chain(base, type))) {
PyErr_SetString(PyExc_TypeError,
"a __bases__ item causes an inheritance cycle");
return -1;
}
}
new_base = best_base(new_bases);
if (new_base == NULL)
return -1;
if (!compatible_for_assignment(type->tp_base, new_base, "__bases__"))
return -1;
Py_INCREF(new_bases);
Py_INCREF(new_base);
old_bases = type->tp_bases;
old_base = type->tp_base;
type->tp_bases = new_bases;
type->tp_base = new_base;
temp = PyList_New(0);
if (temp == NULL)
goto bail;
if (mro_hierarchy(type, temp) < 0)
goto undo;
Py_DECREF(temp);
/* Take no action in case if type->tp_bases has been replaced
through reentrance. */
if (type->tp_bases == new_bases) {
/* any base that was in __bases__ but now isn't, we
need to remove |type| from its tp_subclasses.
conversely, any class now in __bases__ that wasn't
needs to have |type| added to its subclasses. */
/* for now, sod that: just remove from all old_bases,
add to all new_bases */
remove_all_subclasses(type, old_bases);
res = add_all_subclasses(type, new_bases);
update_all_slots(type);
}
Py_DECREF(old_bases);
Py_DECREF(old_base);
assert(_PyType_CheckConsistency(type));
return res;
undo:
for (i = PyList_GET_SIZE(temp) - 1; i >= 0; i--) {
PyTypeObject *cls;
PyObject *new_mro, *old_mro = NULL;
PyArg_UnpackTuple(PyList_GET_ITEM(temp, i),
"", 2, 3, &cls, &new_mro, &old_mro);
/* Do not rollback if cls has a newer version of MRO. */
if (cls->tp_mro == new_mro) {
Py_XINCREF(old_mro);
cls->tp_mro = old_mro;
Py_DECREF(new_mro);
}
}
Py_DECREF(temp);
bail:
if (type->tp_bases == new_bases) {
assert(type->tp_base == new_base);
type->tp_bases = old_bases;
type->tp_base = old_base;
Py_DECREF(new_bases);
Py_DECREF(new_base);
}
else {
Py_DECREF(old_bases);
Py_DECREF(old_base);
}
assert(_PyType_CheckConsistency(type));
return -1;
}
static PyObject *
type_dict(PyTypeObject *type, void *context)
{
if (type->tp_dict == NULL) {
Py_RETURN_NONE;
}
return PyDictProxy_New(type->tp_dict);
}
static PyObject *
type_get_doc(PyTypeObject *type, void *context)
{
PyObject *result;
if (!(type->tp_flags & Py_TPFLAGS_HEAPTYPE) && type->tp_doc != NULL) {
return _PyType_GetDocFromInternalDoc(type->tp_name, type->tp_doc);
}
result = _PyDict_GetItemIdWithError(type->tp_dict, &PyId___doc__);
if (result == NULL) {
if (!PyErr_Occurred()) {
result = Py_None;
Py_INCREF(result);
}
}
else if (Py_TYPE(result)->tp_descr_get) {
result = Py_TYPE(result)->tp_descr_get(result, NULL,
(PyObject *)type);
}
else {
Py_INCREF(result);
}
return result;
}
static PyObject *
type_get_text_signature(PyTypeObject *type, void *context)
{
return _PyType_GetTextSignatureFromInternalDoc(type->tp_name, type->tp_doc);
}
static int
type_set_doc(PyTypeObject *type, PyObject *value, void *context)
{
if (!check_set_special_type_attr(type, value, "__doc__"))
return -1;
PyType_Modified(type);
return _PyDict_SetItemId(type->tp_dict, &PyId___doc__, value);
}
/*[clinic input]
type.__instancecheck__ -> bool
instance: object
/
Check if an object is an instance.
[clinic start generated code]*/
static int
type___instancecheck___impl(PyTypeObject *self, PyObject *instance)
/*[clinic end generated code: output=08b6bf5f591c3618 input=cdbfeaee82c01a0f]*/
{
return _PyObject_RealIsInstance(instance, (PyObject *)self);
}
/*[clinic input]
type.__subclasscheck__ -> bool
subclass: object
/
Check if a class is a subclass.
[clinic start generated code]*/
static int
type___subclasscheck___impl(PyTypeObject *self, PyObject *subclass)
/*[clinic end generated code: output=97a4e51694500941 input=071b2ca9e03355f4]*/
{
return _PyObject_RealIsSubclass(subclass, (PyObject *)self);
}
static PyGetSetDef type_getsets[] = {
{"__name__", (getter)type_name, (setter)type_set_name, NULL},
{"__qualname__", (getter)type_qualname, (setter)type_set_qualname, NULL},
{"__bases__", (getter)type_get_bases, (setter)type_set_bases, NULL},
{"__module__", (getter)type_module, (setter)type_set_module, NULL},
{"__abstractmethods__", (getter)type_abstractmethods,
(setter)type_set_abstractmethods, NULL},
{"__dict__", (getter)type_dict, NULL, NULL},
{"__doc__", (getter)type_get_doc, (setter)type_set_doc, NULL},
{"__text_signature__", (getter)type_get_text_signature, NULL, NULL},
{0}
};
static PyObject *
type_repr(PyTypeObject *type)
{
PyObject *mod, *name, *rtn;
mod = type_module(type, NULL);
if (mod == NULL)
PyErr_Clear();
else if (!PyUnicode_Check(mod)) {
Py_DECREF(mod);
mod = NULL;
}
name = type_qualname(type, NULL);
if (name == NULL) {
Py_XDECREF(mod);
return NULL;
}
if (mod != NULL && !_PyUnicode_EqualToASCIIId(mod, &PyId_builtins))
rtn = PyUnicode_FromFormat("<class '%U.%U'>", mod, name);
else
rtn = PyUnicode_FromFormat("<class '%s'>", type->tp_name);
Py_XDECREF(mod);
Py_DECREF(name);
return rtn;
}
static PyObject *
type_call(PyTypeObject *type, PyObject *args, PyObject *kwds)
{
PyObject *obj;
PyThreadState *tstate = _PyThreadState_GET();
#ifdef Py_DEBUG
/* type_call() must not be called with an exception set,
because it can clear it (directly or indirectly) and so the
caller loses its exception */
assert(!_PyErr_Occurred(tstate));
#endif
/* Special case: type(x) should return Py_TYPE(x) */
/* We only want type itself to accept the one-argument form (#27157) */
if (type == &PyType_Type) {
assert(args != NULL && PyTuple_Check(args));
assert(kwds == NULL || PyDict_Check(kwds));
Py_ssize_t nargs = PyTuple_GET_SIZE(args);
if (nargs == 1 && (kwds == NULL || !PyDict_GET_SIZE(kwds))) {
obj = (PyObject *) Py_TYPE(PyTuple_GET_ITEM(args, 0));
Py_INCREF(obj);
return obj;
}
/* SF bug 475327 -- if that didn't trigger, we need 3
arguments. But PyArg_ParseTuple in type_new may give
a msg saying type() needs exactly 3. */
if (nargs != 3) {
You can’t perform that action at this time.