forked from python/cpython
-
Notifications
You must be signed in to change notification settings - Fork 0
/
object.c
2061 lines (1855 loc) · 47.7 KB
/
object.c
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
/* Generic object operations; and implementation of None (NoObject) */
#include "Python.h"
#ifdef macintosh
#include "macglue.h"
#endif
#ifdef Py_REF_DEBUG
long _Py_RefTotal;
#endif
int Py_DivisionWarningFlag;
/* Object allocation routines used by NEWOBJ and NEWVAROBJ macros.
These are used by the individual routines for object creation.
Do not call them otherwise, they do not initialize the object! */
#ifdef Py_TRACE_REFS
/* Head of circular doubly-linked list of all objects. These are linked
* together via the _ob_prev and _ob_next members of a PyObject, which
* exist only in a Py_TRACE_REFS build.
*/
static PyObject refchain = {&refchain, &refchain};
/* Insert op at the front of the list of all objects. If force is true,
* op is added even if _ob_prev and _ob_next are non-NULL already. If
* force is false amd _ob_prev or _ob_next are non-NULL, do nothing.
* force should be true if and only if op points to freshly allocated,
* uninitialized memory, or you've unlinked op from the list and are
* relinking it into the front.
* Note that objects are normally added to the list via _Py_NewReference,
* which is called by PyObject_Init. Not all objects are initialized that
* way, though; exceptions include statically allocated type objects, and
* statically allocated singletons (like Py_True and Py_None).
*/
void
_Py_AddToAllObjects(PyObject *op, int force)
{
#ifdef Py_DEBUG
if (!force) {
/* If it's initialized memory, op must be in or out of
* the list unambiguously.
*/
assert((op->_ob_prev == NULL) == (op->_ob_next == NULL));
}
#endif
if (force || op->_ob_prev == NULL) {
op->_ob_next = refchain._ob_next;
op->_ob_prev = &refchain;
refchain._ob_next->_ob_prev = op;
refchain._ob_next = op;
}
}
#endif /* Py_TRACE_REFS */
#ifdef COUNT_ALLOCS
static PyTypeObject *type_list;
extern int tuple_zero_allocs, fast_tuple_allocs;
extern int quick_int_allocs, quick_neg_int_allocs;
extern int null_strings, one_strings;
void
dump_counts(void)
{
PyTypeObject *tp;
for (tp = type_list; tp; tp = tp->tp_next)
fprintf(stderr, "%s alloc'd: %d, freed: %d, max in use: %d\n",
tp->tp_name, tp->tp_allocs, tp->tp_frees,
tp->tp_maxalloc);
fprintf(stderr, "fast tuple allocs: %d, empty: %d\n",
fast_tuple_allocs, tuple_zero_allocs);
fprintf(stderr, "fast int allocs: pos: %d, neg: %d\n",
quick_int_allocs, quick_neg_int_allocs);
fprintf(stderr, "null strings: %d, 1-strings: %d\n",
null_strings, one_strings);
}
PyObject *
get_counts(void)
{
PyTypeObject *tp;
PyObject *result;
PyObject *v;
result = PyList_New(0);
if (result == NULL)
return NULL;
for (tp = type_list; tp; tp = tp->tp_next) {
v = Py_BuildValue("(siii)", tp->tp_name, tp->tp_allocs,
tp->tp_frees, tp->tp_maxalloc);
if (v == NULL) {
Py_DECREF(result);
return NULL;
}
if (PyList_Append(result, v) < 0) {
Py_DECREF(v);
Py_DECREF(result);
return NULL;
}
Py_DECREF(v);
}
return result;
}
void
inc_count(PyTypeObject *tp)
{
if (tp->tp_allocs == 0) {
/* first time; insert in linked list */
if (tp->tp_next != NULL) /* sanity check */
Py_FatalError("XXX inc_count sanity check");
tp->tp_next = type_list;
/* Note that as of Python 2.2, heap-allocated type objects
* can go away, but this code requires that they stay alive
* until program exit. That's why we're careful with
* refcounts here. type_list gets a new reference to tp,
* while ownership of the reference type_list used to hold
* (if any) was transferred to tp->tp_next in the line above.
* tp is thus effectively immortal after this.
*/
Py_INCREF(tp);
type_list = tp;
#ifdef Py_TRACE_REFS
/* Also insert in the doubly-linked list of all objects,
* if not already there.
*/
_Py_AddToAllObjects((PyObject *)tp, 0);
#endif
}
tp->tp_allocs++;
if (tp->tp_allocs - tp->tp_frees > tp->tp_maxalloc)
tp->tp_maxalloc = tp->tp_allocs - tp->tp_frees;
}
#endif
#ifdef Py_REF_DEBUG
/* Log a fatal error; doesn't return. */
void
_Py_NegativeRefcount(const char *fname, int lineno, PyObject *op)
{
char buf[300];
PyOS_snprintf(buf, sizeof(buf),
"%s:%i object at %p has negative ref count %i",
fname, lineno, op, op->ob_refcnt);
Py_FatalError(buf);
}
#endif /* Py_REF_DEBUG */
PyObject *
PyObject_Init(PyObject *op, PyTypeObject *tp)
{
if (op == NULL)
return PyErr_NoMemory();
/* Any changes should be reflected in PyObject_INIT (objimpl.h) */
op->ob_type = tp;
_Py_NewReference(op);
return op;
}
PyVarObject *
PyObject_InitVar(PyVarObject *op, PyTypeObject *tp, int size)
{
if (op == NULL)
return (PyVarObject *) PyErr_NoMemory();
/* Any changes should be reflected in PyObject_INIT_VAR */
op->ob_size = size;
op->ob_type = tp;
_Py_NewReference((PyObject *)op);
return op;
}
PyObject *
_PyObject_New(PyTypeObject *tp)
{
PyObject *op;
op = (PyObject *) PyObject_MALLOC(_PyObject_SIZE(tp));
if (op == NULL)
return PyErr_NoMemory();
return PyObject_INIT(op, tp);
}
PyVarObject *
_PyObject_NewVar(PyTypeObject *tp, int nitems)
{
PyVarObject *op;
const size_t size = _PyObject_VAR_SIZE(tp, nitems);
op = (PyVarObject *) PyObject_MALLOC(size);
if (op == NULL)
return (PyVarObject *)PyErr_NoMemory();
return PyObject_INIT_VAR(op, tp, nitems);
}
/* for binary compatibility with 2.2 */
#undef _PyObject_Del
void
_PyObject_Del(PyObject *op)
{
PyObject_FREE(op);
}
/* Implementation of PyObject_Print with recursion checking */
static int
internal_print(PyObject *op, FILE *fp, int flags, int nesting)
{
int ret = 0;
if (nesting > 10) {
PyErr_SetString(PyExc_RuntimeError, "print recursion");
return -1;
}
if (PyErr_CheckSignals())
return -1;
#ifdef USE_STACKCHECK
if (PyOS_CheckStack()) {
PyErr_SetString(PyExc_MemoryError, "stack overflow");
return -1;
}
#endif
clearerr(fp); /* Clear any previous error condition */
if (op == NULL) {
fprintf(fp, "<nil>");
}
else {
if (op->ob_refcnt <= 0)
fprintf(fp, "<refcnt %u at %p>",
op->ob_refcnt, op);
else if (op->ob_type->tp_print == NULL) {
PyObject *s;
if (flags & Py_PRINT_RAW)
s = PyObject_Str(op);
else
s = PyObject_Repr(op);
if (s == NULL)
ret = -1;
else {
ret = internal_print(s, fp, Py_PRINT_RAW,
nesting+1);
}
Py_XDECREF(s);
}
else
ret = (*op->ob_type->tp_print)(op, fp, flags);
}
if (ret == 0) {
if (ferror(fp)) {
PyErr_SetFromErrno(PyExc_IOError);
clearerr(fp);
ret = -1;
}
}
return ret;
}
int
PyObject_Print(PyObject *op, FILE *fp, int flags)
{
return internal_print(op, fp, flags, 0);
}
/* For debugging convenience. See Misc/gdbinit for some useful gdb hooks */
void _PyObject_Dump(PyObject* op)
{
if (op == NULL)
fprintf(stderr, "NULL\n");
else {
fprintf(stderr, "object : ");
(void)PyObject_Print(op, stderr, 0);
fprintf(stderr, "\n"
"type : %s\n"
"refcount: %d\n"
"address : %p\n",
op->ob_type==NULL ? "NULL" : op->ob_type->tp_name,
op->ob_refcnt,
op);
}
}
PyObject *
PyObject_Repr(PyObject *v)
{
if (PyErr_CheckSignals())
return NULL;
#ifdef USE_STACKCHECK
if (PyOS_CheckStack()) {
PyErr_SetString(PyExc_MemoryError, "stack overflow");
return NULL;
}
#endif
if (v == NULL)
return PyString_FromString("<NULL>");
else if (v->ob_type->tp_repr == NULL)
return PyString_FromFormat("<%s object at %p>",
v->ob_type->tp_name, v);
else {
PyObject *res;
res = (*v->ob_type->tp_repr)(v);
if (res == NULL)
return NULL;
#ifdef Py_USING_UNICODE
if (PyUnicode_Check(res)) {
PyObject* str;
str = PyUnicode_AsUnicodeEscapeString(res);
Py_DECREF(res);
if (str)
res = str;
else
return NULL;
}
#endif
if (!PyString_Check(res)) {
PyErr_Format(PyExc_TypeError,
"__repr__ returned non-string (type %.200s)",
res->ob_type->tp_name);
Py_DECREF(res);
return NULL;
}
return res;
}
}
PyObject *
PyObject_Str(PyObject *v)
{
PyObject *res;
if (v == NULL)
return PyString_FromString("<NULL>");
if (PyString_CheckExact(v)) {
Py_INCREF(v);
return v;
}
if (v->ob_type->tp_str == NULL)
return PyObject_Repr(v);
res = (*v->ob_type->tp_str)(v);
if (res == NULL)
return NULL;
#ifdef Py_USING_UNICODE
if (PyUnicode_Check(res)) {
PyObject* str;
str = PyUnicode_AsEncodedString(res, NULL, NULL);
Py_DECREF(res);
if (str)
res = str;
else
return NULL;
}
#endif
if (!PyString_Check(res)) {
PyErr_Format(PyExc_TypeError,
"__str__ returned non-string (type %.200s)",
res->ob_type->tp_name);
Py_DECREF(res);
return NULL;
}
return res;
}
#ifdef Py_USING_UNICODE
PyObject *
PyObject_Unicode(PyObject *v)
{
PyObject *res;
if (v == NULL)
res = PyString_FromString("<NULL>");
if (PyUnicode_CheckExact(v)) {
Py_INCREF(v);
return v;
}
if (PyUnicode_Check(v)) {
/* For a Unicode subtype that's not a Unicode object,
return a true Unicode object with the same data. */
return PyUnicode_FromUnicode(PyUnicode_AS_UNICODE(v),
PyUnicode_GET_SIZE(v));
}
if (PyString_Check(v)) {
Py_INCREF(v);
res = v;
}
else {
PyObject *func;
static PyObject *unicodestr;
/* XXX As soon as we have a tp_unicode slot, we should
check this before trying the __unicode__
method. */
if (unicodestr == NULL) {
unicodestr= PyString_InternFromString(
"__unicode__");
if (unicodestr == NULL)
return NULL;
}
func = PyObject_GetAttr(v, unicodestr);
if (func != NULL) {
res = PyEval_CallObject(func, (PyObject *)NULL);
Py_DECREF(func);
}
else {
PyErr_Clear();
if (v->ob_type->tp_str != NULL)
res = (*v->ob_type->tp_str)(v);
else
res = PyObject_Repr(v);
}
}
if (res == NULL)
return NULL;
if (!PyUnicode_Check(res)) {
PyObject *str;
str = PyUnicode_FromEncodedObject(res, NULL, "strict");
Py_DECREF(res);
if (str)
res = str;
else
return NULL;
}
return res;
}
#endif
/* Helper to warn about deprecated tp_compare return values. Return:
-2 for an exception;
-1 if v < w;
0 if v == w;
1 if v > w.
(This function cannot return 2.)
*/
static int
adjust_tp_compare(int c)
{
if (PyErr_Occurred()) {
if (c != -1 && c != -2) {
PyObject *t, *v, *tb;
PyErr_Fetch(&t, &v, &tb);
if (PyErr_Warn(PyExc_RuntimeWarning,
"tp_compare didn't return -1 or -2 "
"for exception") < 0) {
Py_XDECREF(t);
Py_XDECREF(v);
Py_XDECREF(tb);
}
else
PyErr_Restore(t, v, tb);
}
return -2;
}
else if (c < -1 || c > 1) {
if (PyErr_Warn(PyExc_RuntimeWarning,
"tp_compare didn't return -1, 0 or 1") < 0)
return -2;
else
return c < -1 ? -1 : 1;
}
else {
assert(c >= -1 && c <= 1);
return c;
}
}
/* Macro to get the tp_richcompare field of a type if defined */
#define RICHCOMPARE(t) (PyType_HasFeature((t), Py_TPFLAGS_HAVE_RICHCOMPARE) \
? (t)->tp_richcompare : NULL)
/* Map rich comparison operators to their swapped version, e.g. LT --> GT */
static int swapped_op[] = {Py_GT, Py_GE, Py_EQ, Py_NE, Py_LT, Py_LE};
/* Try a genuine rich comparison, returning an object. Return:
NULL for exception;
NotImplemented if this particular rich comparison is not implemented or
undefined;
some object not equal to NotImplemented if it is implemented
(this latter object may not be a Boolean).
*/
static PyObject *
try_rich_compare(PyObject *v, PyObject *w, int op)
{
richcmpfunc f;
PyObject *res;
if (v->ob_type != w->ob_type &&
PyType_IsSubtype(w->ob_type, v->ob_type) &&
(f = RICHCOMPARE(w->ob_type)) != NULL) {
res = (*f)(w, v, swapped_op[op]);
if (res != Py_NotImplemented)
return res;
Py_DECREF(res);
}
if ((f = RICHCOMPARE(v->ob_type)) != NULL) {
res = (*f)(v, w, op);
if (res != Py_NotImplemented)
return res;
Py_DECREF(res);
}
if ((f = RICHCOMPARE(w->ob_type)) != NULL) {
return (*f)(w, v, swapped_op[op]);
}
res = Py_NotImplemented;
Py_INCREF(res);
return res;
}
/* Try a genuine rich comparison, returning an int. Return:
-1 for exception (including the case where try_rich_compare() returns an
object that's not a Boolean);
0 if the outcome is false;
1 if the outcome is true;
2 if this particular rich comparison is not implemented or undefined.
*/
static int
try_rich_compare_bool(PyObject *v, PyObject *w, int op)
{
PyObject *res;
int ok;
if (RICHCOMPARE(v->ob_type) == NULL && RICHCOMPARE(w->ob_type) == NULL)
return 2; /* Shortcut, avoid INCREF+DECREF */
res = try_rich_compare(v, w, op);
if (res == NULL)
return -1;
if (res == Py_NotImplemented) {
Py_DECREF(res);
return 2;
}
ok = PyObject_IsTrue(res);
Py_DECREF(res);
return ok;
}
/* Try rich comparisons to determine a 3-way comparison. Return:
-2 for an exception;
-1 if v < w;
0 if v == w;
1 if v > w;
2 if this particular rich comparison is not implemented or undefined.
*/
static int
try_rich_to_3way_compare(PyObject *v, PyObject *w)
{
static struct { int op; int outcome; } tries[3] = {
/* Try this operator, and if it is true, use this outcome: */
{Py_EQ, 0},
{Py_LT, -1},
{Py_GT, 1},
};
int i;
if (RICHCOMPARE(v->ob_type) == NULL && RICHCOMPARE(w->ob_type) == NULL)
return 2; /* Shortcut */
for (i = 0; i < 3; i++) {
switch (try_rich_compare_bool(v, w, tries[i].op)) {
case -1:
return -2;
case 1:
return tries[i].outcome;
}
}
return 2;
}
/* Try a 3-way comparison, returning an int. Return:
-2 for an exception;
-1 if v < w;
0 if v == w;
1 if v > w;
2 if this particular 3-way comparison is not implemented or undefined.
*/
static int
try_3way_compare(PyObject *v, PyObject *w)
{
int c;
cmpfunc f;
/* Comparisons involving instances are given to instance_compare,
which has the same return conventions as this function. */
f = v->ob_type->tp_compare;
if (PyInstance_Check(v))
return (*f)(v, w);
if (PyInstance_Check(w))
return (*w->ob_type->tp_compare)(v, w);
/* If both have the same (non-NULL) tp_compare, use it. */
if (f != NULL && f == w->ob_type->tp_compare) {
c = (*f)(v, w);
return adjust_tp_compare(c);
}
/* If either tp_compare is _PyObject_SlotCompare, that's safe. */
if (f == _PyObject_SlotCompare ||
w->ob_type->tp_compare == _PyObject_SlotCompare)
return _PyObject_SlotCompare(v, w);
/* Try coercion; if it fails, give up */
c = PyNumber_CoerceEx(&v, &w);
if (c < 0)
return -2;
if (c > 0)
return 2;
/* Try v's comparison, if defined */
if ((f = v->ob_type->tp_compare) != NULL) {
c = (*f)(v, w);
Py_DECREF(v);
Py_DECREF(w);
return adjust_tp_compare(c);
}
/* Try w's comparison, if defined */
if ((f = w->ob_type->tp_compare) != NULL) {
c = (*f)(w, v); /* swapped! */
Py_DECREF(v);
Py_DECREF(w);
c = adjust_tp_compare(c);
if (c >= -1)
return -c; /* Swapped! */
else
return c;
}
/* No comparison defined */
Py_DECREF(v);
Py_DECREF(w);
return 2;
}
/* Final fallback 3-way comparison, returning an int. Return:
-2 if an error occurred;
-1 if v < w;
0 if v == w;
1 if v > w.
*/
static int
default_3way_compare(PyObject *v, PyObject *w)
{
int c;
char *vname, *wname;
if (v->ob_type == w->ob_type) {
/* When comparing these pointers, they must be cast to
* integer types (i.e. Py_uintptr_t, our spelling of C9X's
* uintptr_t). ANSI specifies that pointer compares other
* than == and != to non-related structures are undefined.
*/
Py_uintptr_t vv = (Py_uintptr_t)v;
Py_uintptr_t ww = (Py_uintptr_t)w;
return (vv < ww) ? -1 : (vv > ww) ? 1 : 0;
}
#ifdef Py_USING_UNICODE
/* Special case for Unicode */
if (PyUnicode_Check(v) || PyUnicode_Check(w)) {
c = PyUnicode_Compare(v, w);
if (!PyErr_Occurred())
return c;
/* TypeErrors are ignored: if Unicode coercion fails due
to one of the arguments not having the right type, we
continue as defined by the coercion protocol (see
above). Luckily, decoding errors are reported as
ValueErrors and are not masked by this technique. */
if (!PyErr_ExceptionMatches(PyExc_TypeError))
return -2;
PyErr_Clear();
}
#endif
/* None is smaller than anything */
if (v == Py_None)
return -1;
if (w == Py_None)
return 1;
/* different type: compare type names; numbers are smaller */
if (PyNumber_Check(v))
vname = "";
else
vname = v->ob_type->tp_name;
if (PyNumber_Check(w))
wname = "";
else
wname = w->ob_type->tp_name;
c = strcmp(vname, wname);
if (c < 0)
return -1;
if (c > 0)
return 1;
/* Same type name, or (more likely) incomparable numeric types */
return ((Py_uintptr_t)(v->ob_type) < (
Py_uintptr_t)(w->ob_type)) ? -1 : 1;
}
#define CHECK_TYPES(o) PyType_HasFeature((o)->ob_type, Py_TPFLAGS_CHECKTYPES)
/* Do a 3-way comparison, by hook or by crook. Return:
-2 for an exception (but see below);
-1 if v < w;
0 if v == w;
1 if v > w;
BUT: if the object implements a tp_compare function, it returns
whatever this function returns (whether with an exception or not).
*/
static int
do_cmp(PyObject *v, PyObject *w)
{
int c;
cmpfunc f;
if (v->ob_type == w->ob_type
&& (f = v->ob_type->tp_compare) != NULL) {
c = (*f)(v, w);
if (PyInstance_Check(v)) {
/* Instance tp_compare has a different signature.
But if it returns undefined we fall through. */
if (c != 2)
return c;
/* Else fall through to try_rich_to_3way_compare() */
}
else
return adjust_tp_compare(c);
}
/* We only get here if one of the following is true:
a) v and w have different types
b) v and w have the same type, which doesn't have tp_compare
c) v and w are instances, and either __cmp__ is not defined or
__cmp__ returns NotImplemented
*/
c = try_rich_to_3way_compare(v, w);
if (c < 2)
return c;
c = try_3way_compare(v, w);
if (c < 2)
return c;
return default_3way_compare(v, w);
}
/* Compare v to w. Return
-1 if v < w or exception (PyErr_Occurred() true in latter case).
0 if v == w.
1 if v > w.
XXX The docs (C API manual) say the return value is undefined in case
XXX of error.
*/
int
PyObject_Compare(PyObject *v, PyObject *w)
{
PyTypeObject *vtp;
int result;
if (v == NULL || w == NULL) {
PyErr_BadInternalCall();
return -1;
}
if (v == w)
return 0;
vtp = v->ob_type;
if (Py_EnterRecursiveCall(" in cmp"))
return -1;
result = do_cmp(v, w);
Py_LeaveRecursiveCall();
return result < 0 ? -1 : result;
}
/* Return (new reference to) Py_True or Py_False. */
static PyObject *
convert_3way_to_object(int op, int c)
{
PyObject *result;
switch (op) {
case Py_LT: c = c < 0; break;
case Py_LE: c = c <= 0; break;
case Py_EQ: c = c == 0; break;
case Py_NE: c = c != 0; break;
case Py_GT: c = c > 0; break;
case Py_GE: c = c >= 0; break;
}
result = c ? Py_True : Py_False;
Py_INCREF(result);
return result;
}
/* We want a rich comparison but don't have one. Try a 3-way cmp instead.
Return
NULL if error
Py_True if v op w
Py_False if not (v op w)
*/
static PyObject *
try_3way_to_rich_compare(PyObject *v, PyObject *w, int op)
{
int c;
c = try_3way_compare(v, w);
if (c >= 2)
c = default_3way_compare(v, w);
if (c <= -2)
return NULL;
return convert_3way_to_object(op, c);
}
/* Do rich comparison on v and w. Return
NULL if error
Else a new reference to an object other than Py_NotImplemented, usually(?):
Py_True if v op w
Py_False if not (v op w)
*/
static PyObject *
do_richcmp(PyObject *v, PyObject *w, int op)
{
PyObject *res;
res = try_rich_compare(v, w, op);
if (res != Py_NotImplemented)
return res;
Py_DECREF(res);
return try_3way_to_rich_compare(v, w, op);
}
/* Return:
NULL for exception;
some object not equal to NotImplemented if it is implemented
(this latter object may not be a Boolean).
*/
PyObject *
PyObject_RichCompare(PyObject *v, PyObject *w, int op)
{
PyObject *res;
assert(Py_LT <= op && op <= Py_GE);
if (Py_EnterRecursiveCall(" in cmp"))
return NULL;
/* If the types are equal, and not old-style instances, try to
get out cheap (don't bother with coercions etc.). */
if (v->ob_type == w->ob_type && !PyInstance_Check(v)) {
cmpfunc fcmp;
richcmpfunc frich = RICHCOMPARE(v->ob_type);
/* If the type has richcmp, try it first. try_rich_compare
tries it two-sided, which is not needed since we've a
single type only. */
if (frich != NULL) {
res = (*frich)(v, w, op);
if (res != Py_NotImplemented)
goto Done;
Py_DECREF(res);
}
/* No richcmp, or this particular richmp not implemented.
Try 3-way cmp. */
fcmp = v->ob_type->tp_compare;
if (fcmp != NULL) {
int c = (*fcmp)(v, w);
c = adjust_tp_compare(c);
if (c == -2) {
res = NULL;
goto Done;
}
res = convert_3way_to_object(op, c);
goto Done;
}
}
/* Fast path not taken, or couldn't deliver a useful result. */
res = do_richcmp(v, w, op);
Done:
Py_LeaveRecursiveCall();
return res;
}
/* Return -1 if error; 1 if v op w; 0 if not (v op w). */
int
PyObject_RichCompareBool(PyObject *v, PyObject *w, int op)
{
PyObject *res = PyObject_RichCompare(v, w, op);
int ok;
if (res == NULL)
return -1;
if (PyBool_Check(res))
ok = (res == Py_True);
else
ok = PyObject_IsTrue(res);
Py_DECREF(res);
return ok;
}
/* Set of hash utility functions to help maintaining the invariant that
iff a==b then hash(a)==hash(b)
All the utility functions (_Py_Hash*()) return "-1" to signify an error.
*/
long
_Py_HashDouble(double v)
{
double intpart, fractpart;
int expo;
long hipart;
long x; /* the final hash value */
/* This is designed so that Python numbers of different types
* that compare equal hash to the same value; otherwise comparisons
* of mapping keys will turn out weird.
*/
#ifdef MPW /* MPW C modf expects pointer to extended as second argument */
{
extended e;
fractpart = modf(v, &e);
intpart = e;
}
#else
fractpart = modf(v, &intpart);
#endif
if (fractpart == 0.0) {
/* This must return the same hash as an equal int or long. */
if (intpart > LONG_MAX || -intpart > LONG_MAX) {
/* Convert to long and use its hash. */
PyObject *plong; /* converted to Python long */
if (Py_IS_INFINITY(intpart))
/* can't convert to long int -- arbitrary */
v = v < 0 ? -271828.0 : 314159.0;
plong = PyLong_FromDouble(v);
if (plong == NULL)
return -1;
x = PyObject_Hash(plong);
Py_DECREF(plong);
return x;
}
/* Fits in a C long == a Python int, so is its own hash. */
x = (long)intpart;
if (x == -1)
x = -2;
return x;
}
/* The fractional part is non-zero, so we don't have to worry about
* making this match the hash of some other type.
* Use frexp to get at the bits in the double.
* Since the VAX D double format has 56 mantissa bits, which is the
* most of any double format in use, each of these parts may have as
* many as (but no more than) 56 significant bits.
* So, assuming sizeof(long) >= 4, each part can be broken into two
* longs; frexp and multiplication are used to do that.
* Also, since the Cray double format has 15 exponent bits, which is
* the most of any double format in use, shifting the exponent field
* left by 15 won't overflow a long (again assuming sizeof(long) >= 4).
*/
v = frexp(v, &expo);
v *= 2147483648.0; /* 2**31 */
hipart = (long)v; /* take the top 32 bits */
v = (v - (double)hipart) * 2147483648.0; /* get the next 32 bits */
x = hipart + (long)v + (expo << 15);
if (x == -1)
x = -2;
return x;
}
long
_Py_HashPointer(void *p)
{
#if SIZEOF_LONG >= SIZEOF_VOID_P
return (long)p;
#else
/* convert to a Python long and hash that */
PyObject* longobj;
long x;
if ((longobj = PyLong_FromVoidPtr(p)) == NULL) {
x = -1;
goto finally;
}
x = PyObject_Hash(longobj);
finally:
Py_XDECREF(longobj);
return x;
#endif
}
long
PyObject_Hash(PyObject *v)
{
PyTypeObject *tp = v->ob_type;
if (tp->tp_hash != NULL)
return (*tp->tp_hash)(v);
if (tp->tp_compare == NULL && RICHCOMPARE(tp) == NULL) {
return _Py_HashPointer(v); /* Use address as hash value */
}
/* If there's a cmp but no hash defined, the object can't be hashed */
PyErr_SetString(PyExc_TypeError, "unhashable type");
return -1;
}
PyObject *