summaryrefslogtreecommitdiff
path: root/Python/errors.c
blob: aed2bdc12d6b1734b58c8e8f86cc96ccae3b84c2 (plain)
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
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137

/* Error handling */

#include "Python.h"

#ifndef __STDC__
#ifndef MS_WINDOWS
extern char *strerror(int);
#endif
#endif

#ifdef MS_WINDOWS
#include <windows.h>
#include <winbase.h>
#endif

#include <ctype.h>

#ifdef __cplusplus
extern "C" {
#endif

_Py_IDENTIFIER(builtins);
_Py_IDENTIFIER(stderr);


void
PyErr_Restore(PyObject *type, PyObject *value, PyObject *traceback)
{
    PyThreadState *tstate = PyThreadState_GET();
    PyObject *oldtype, *oldvalue, *oldtraceback;

    if (traceback != NULL && !PyTraceBack_Check(traceback)) {
        /* XXX Should never happen -- fatal error instead? */
        /* Well, it could be None. */
        Py_DECREF(traceback);
        traceback = NULL;
    }

    /* Save these in locals to safeguard against recursive
       invocation through Py_XDECREF */
    oldtype = tstate->curexc_type;
    oldvalue = tstate->curexc_value;
    oldtraceback = tstate->curexc_traceback;

    tstate->curexc_type = type;
    tstate->curexc_value = value;
    tstate->curexc_traceback = traceback;

    Py_XDECREF(oldtype);
    Py_XDECREF(oldvalue);
    Py_XDECREF(oldtraceback);
}

void
PyErr_SetObject(PyObject *exception, PyObject *value)
{
    PyThreadState *tstate = PyThreadState_GET();
    PyObject *exc_value;
    PyObject *tb = NULL;

    if (exception != NULL &&
        !PyExceptionClass_Check(exception)) {
        PyErr_Format(PyExc_SystemError,
                     "exception %R not a BaseException subclass",
                     exception);
        return;
    }
    Py_XINCREF(value);
    exc_value = tstate->exc_value;
    if (exc_value != NULL && exc_value != Py_None) {
        /* Implicit exception chaining */
        Py_INCREF(exc_value);
        if (value == NULL || !PyExceptionInstance_Check(value)) {
            /* We must normalize the value right now */
            PyObject *args, *fixed_value;

            /* Issue #23571: PyEval_CallObject() must not be called with an
               exception set */
            PyErr_Clear();

            if (value == NULL || value == Py_None)
                args = PyTuple_New(0);
            else if (PyTuple_Check(value)) {
                Py_INCREF(value);
                args = value;
            }
            else
                args = PyTuple_Pack(1, value);
            fixed_value = args ?
                PyEval_CallObject(exception, args) : NULL;
            Py_XDECREF(args);
            Py_XDECREF(value);
            if (fixed_value == NULL)
                return;
            value = fixed_value;
        }
        /* Avoid reference cycles through the context chain.
           This is O(chain length) but context chains are
           usually very short. Sensitive readers may try
           to inline the call to PyException_GetContext. */
        if (exc_value != value) {
            PyObject *o = exc_value, *context;
            while ((context = PyException_GetContext(o))) {
                Py_DECREF(context);
                if (context == value) {
                    PyException_SetContext(o, NULL);
                    break;
                }
                o = context;
            }
            PyException_SetContext(value, exc_value);
        } else {
            Py_DECREF(exc_value);
        }
    }
    if (value != NULL && PyExceptionInstance_Check(value))
        tb = PyException_GetTraceback(value);
    Py_XINCREF(exception);
    PyErr_Restore(exception, value, tb);
}

/* Set a key error with the specified argument, wrapping it in a
 * tuple automatically so that tuple keys are not unpacked as the
 * exception arguments. */
void
_PyErr_SetKeyError(PyObject *arg)
{
    PyObject *tup;
    tup = PyTuple_Pack(1, arg);
    if (!tup)
        return; /* caller will expect error to be set anyway */
    PyErr_SetObject(PyExc_KeyError, tup);
    Py_DECREF(tup);
}

void
PyErr_SetNone(PyObject *exception)
{
    PyErr_SetObject(exception, (PyObject *)NULL);
}

void
PyErr_SetString(PyObject *exception, const char *string)
{
    PyObject *value = PyUnicode_FromString(string);
    PyErr_SetObject(exception, value);
    Py_XDECREF(value);
}


PyObject *
PyErr_Occurred(void)
{
    /* If there is no thread state, PyThreadState_GET calls
       Py_FatalError, which calls PyErr_Occurred.  To avoid the
       resulting infinite loop, we inline PyThreadState_GET here and
       treat no thread as no error. */
    PyThreadState *tstate =
        ((PyThreadState*)_Py_atomic_load_relaxed(&_PyThreadState_Current));

    return tstate == NULL ? NULL : tstate->curexc_type;
}


int
PyErr_GivenExceptionMatches(PyObject *err, PyObject *exc)
{
    if (err == NULL || exc == NULL) {
        /* maybe caused by "import exceptions" that failed early on */
        return 0;
    }
    if (PyTuple_Check(exc)) {
        Py_ssize_t i, n;
        n = PyTuple_Size(exc);
        for (i = 0; i < n; i++) {
            /* Test recursively */
             if (PyErr_GivenExceptionMatches(
                 err, PyTuple_GET_ITEM(exc, i)))
             {
                 return 1;
             }
        }
        return 0;
    }
    /* err might be an instance, so check its class. */
    if (PyExceptionInstance_Check(err))
        err = PyExceptionInstance_Class(err);

    if (PyExceptionClass_Check(err) && PyExceptionClass_Check(exc)) {
        int res = 0;
        PyObject *exception, *value, *tb;
        PyErr_Fetch(&exception, &value, &tb);
        /* PyObject_IsSubclass() can recurse and therefore is
           not safe (see test_bad_getattr in test.pickletester). */
        res = PyType_IsSubtype((PyTypeObject *)err, (PyTypeObject *)exc);
        /* This function must not fail, so print the error here */
        if (res == -1) {
            PyErr_WriteUnraisable(err);
            res = 0;
        }
        PyErr_Restore(exception, value, tb);
        return res;
    }

    return err == exc;
}


int
PyErr_ExceptionMatches(PyObject *exc)
{
    return PyErr_GivenExceptionMatches(PyErr_Occurred(), exc);
}


/* Used in many places to normalize a raised exception, including in
   eval_code2(), do_raise(), and PyErr_Print()

   XXX: should PyErr_NormalizeException() also call
            PyException_SetTraceback() with the resulting value and tb?
*/
void
PyErr_NormalizeException(PyObject **exc, PyObject **val, PyObject **tb)
{
    PyObject *type = *exc;
    PyObject *value = *val;
    PyObject *inclass = NULL;
    PyObject *initial_tb = NULL;
    PyThreadState *tstate = NULL;

    if (type == NULL) {
        /* There was no exception, so nothing to do. */
        return;
    }

    /* If PyErr_SetNone() was used, the value will have been actually
       set to NULL.
    */
    if (!value) {
        value = Py_None;
        Py_INCREF(value);
    }

    if (PyExceptionInstance_Check(value))
        inclass = PyExceptionInstance_Class(value);

    /* Normalize the exception so that if the type is a class, the
       value will be an instance.
    */
    if (PyExceptionClass_Check(type)) {
        int is_subclass;
        if (inclass) {
            is_subclass = PyObject_IsSubclass(inclass, type);
            if (is_subclass < 0)
                goto finally;
        }
        else
            is_subclass = 0;

        /* if the value was not an instance, or is not an instance
           whose class is (or is derived from) type, then use the
           value as an argument to instantiation of the type
           class.
        */
        if (!inclass || !is_subclass) {
            PyObject *args, *res;

            if (value == Py_None)
                args = PyTuple_New(0);
            else if (PyTuple_Check(value)) {
                Py_INCREF(value);
                args = value;
            }
            else
                args = PyTuple_Pack(1, value);

            if (args == NULL)
                goto finally;
            res = PyEval_CallObject(type, args);
            Py_DECREF(args);
            if (res == NULL)
                goto finally;
            Py_DECREF(value);
            value = res;
        }
        /* if the class of the instance doesn't exactly match the
           class of the type, believe the instance
        */
        else if (inclass != type) {
            Py_DECREF(type);
            type = inclass;
            Py_INCREF(type);
        }
    }
    *exc = type;
    *val = value;
    return;
finally:
    Py_DECREF(type);
    Py_DECREF(value);
    /* If the new exception doesn't set a traceback and the old
       exception had a traceback, use the old traceback for the
       new exception.  It's better than nothing.
    */
    initial_tb = *tb;
    PyErr_Fetch(exc, val, tb);
    if (initial_tb != NULL) {
        if (*tb == NULL)
            *tb = initial_tb;
        else
            Py_DECREF(initial_tb);
    }
    /* normalize recursively */
    tstate = PyThreadState_GET();
    if (++tstate->recursion_depth > Py_GetRecursionLimit()) {
        --tstate->recursion_depth;
        /* throw away the old exception... */
        Py_DECREF(*exc);
        Py_DECREF(*val);
        /* ... and use the recursion error instead */
        *exc = PyExc_RecursionError;
        *val = PyExc_RecursionErrorInst;
        Py_INCREF(*exc);
        Py_INCREF(*val);
        /* just keeping the old traceback */
        return;
    }
    PyErr_NormalizeException(exc, val, tb);
    --tstate->recursion_depth;
}


void
PyErr_Fetch(PyObject **p_type, PyObject **p_value, PyObject **p_traceback)
{
    PyThreadState *tstate = PyThreadState_GET();

    *p_type = tstate->curexc_type;
    *p_value = tstate->curexc_value;
    *p_traceback = tstate->curexc_traceback;

    tstate->curexc_type = NULL;
    tstate->curexc_value = NULL;
    tstate->curexc_traceback = NULL;
}

void
PyErr_Clear(void)
{
    PyErr_Restore(NULL, NULL, NULL);
}

void
PyErr_GetExcInfo(PyObject **p_type, PyObject **p_value, PyObject **p_traceback)
{
    PyThreadState *tstate = PyThreadState_GET();

    *p_type = tstate->exc_type;
    *p_value = tstate->exc_value;
    *p_traceback = tstate->exc_traceback;

    Py_XINCREF(*p_type);
    Py_XINCREF(*p_value);
    Py_XINCREF(*p_traceback);
}

void
PyErr_SetExcInfo(PyObject *p_type, PyObject *p_value, PyObject *p_traceback)
{
    PyObject *oldtype, *oldvalue, *oldtraceback;
    PyThreadState *tstate = PyThreadState_GET();

    oldtype = tstate->exc_type;
    oldvalue = tstate->exc_value;
    oldtraceback = tstate->exc_traceback;

    tstate->exc_type = p_type;
    tstate->exc_value = p_value;
    tstate->exc_traceback = p_traceback;

    Py_XDECREF(oldtype);
    Py_XDECREF(oldvalue);
    Py_XDECREF(oldtraceback);
}

/* Like PyErr_Restore(), but if an exception is already set,
   set the context associated with it.
 */
void
_PyErr_ChainExceptions(PyObject *exc, PyObject *val, PyObject *tb)
{
    if (exc == NULL)
        return;

    if (PyErr_Occurred()) {
        PyObject *exc2, *val2, *tb2;
        PyErr_Fetch(&exc2, &val2, &tb2);
        PyErr_NormalizeException(&exc, &val, &tb);
        Py_DECREF(exc);
        Py_XDECREF(tb);
        PyErr_NormalizeException(&exc2, &val2, &tb2);
        PyException_SetContext(val2, val);
        PyErr_Restore(exc2, val2, tb2);
    }
    else {
        PyErr_Restore(exc, val, tb);
    }
}

/* Convenience functions to set a type error exception and return 0 */

int
PyErr_BadArgument(void)
{
    PyErr_SetString(PyExc_TypeError,
                    "bad argument type for built-in operation");
    return 0;
}

PyObject *
PyErr_NoMemory(void)
{
    if (Py_TYPE(PyExc_MemoryError) == NULL) {
        /* PyErr_NoMemory() has been called before PyExc_MemoryError has been
           initialized by _PyExc_Init() */
        Py_FatalError("Out of memory and PyExc_MemoryError is not "
                      "initialized yet");
    }
    PyErr_SetNone(PyExc_MemoryError);
    return NULL;
}

PyObject *
PyErr_SetFromErrnoWithFilenameObject(PyObject *exc, PyObject *filenameObject)
{
    return PyErr_SetFromErrnoWithFilenameObjects(exc, filenameObject, NULL);
}

PyObject *
PyErr_SetFromErrnoWithFilenameObjects(PyObject *exc, PyObject *filenameObject, PyObject *filenameObject2)
{
    PyObject *message;
    PyObject *v, *args;
    int i = errno;
#ifdef MS_WINDOWS
    WCHAR *s_buf = NULL;
#endif /* Unix/Windows */

#ifdef EINTR
    if (i == EINTR && PyErr_CheckSignals())
        return NULL;
#endif

#ifndef MS_WINDOWS
    if (i != 0) {
        char *s = strerror(i);
        message = PyUnicode_DecodeLocale(s, "surrogateescape");
    }
    else {
        /* Sometimes errno didn't get set */
        message = PyUnicode_FromString("Error");
    }
#else
    if (i == 0)
        message = PyUnicode_FromString("Error"); /* Sometimes errno didn't get set */
    else
    {
        /* Note that the Win32 errors do not lineup with the
           errno error.  So if the error is in the MSVC error
           table, we use it, otherwise we assume it really _is_
           a Win32 error code
        */
        if (i > 0 && i < _sys_nerr) {
            message = PyUnicode_FromString(_sys_errlist[i]);
        }
        else {
            int len = FormatMessageW(
                FORMAT_MESSAGE_ALLOCATE_BUFFER |
                FORMAT_MESSAGE_FROM_SYSTEM |
                FORMAT_MESSAGE_IGNORE_INSERTS,
                NULL,                   /* no message source */
                i,
                MAKELANGID(LANG_NEUTRAL,
                           SUBLANG_DEFAULT),
                           /* Default language */
                (LPWSTR) &s_buf,
                0,                      /* size not used */
                NULL);                  /* no args */
            if (len==0) {
                /* Only ever seen this in out-of-mem
                   situations */
                s_buf = NULL;
                message = PyUnicode_FromFormat("Windows Error 0x%x", i);
            } else {
                /* remove trailing cr/lf and dots */
                while (len > 0 && (s_buf[len-1] <= L' ' || s_buf[len-1] == L'.'))
                    s_buf[--len] = L'\0';
                message = PyUnicode_FromWideChar(s_buf, len);
            }
        }
    }
#endif /* Unix/Windows */

    if (message == NULL)
    {
#ifdef MS_WINDOWS
        LocalFree(s_buf);
#endif
        return NULL;
    }

    if (filenameObject != NULL) {
        if (filenameObject2 != NULL)
            args = Py_BuildValue("(iOOiO)", i, message, filenameObject, 0, filenameObject2);
        else
            args = Py_BuildValue("(iOO)", i, message, filenameObject);
    } else {
        assert(filenameObject2 == NULL);
        args = Py_BuildValue("(iO)", i, message);
    }
    Py_DECREF(message);

    if (args != NULL) {
        v = PyObject_Call(exc, args, NULL);
        Py_DECREF(args);
        if (v != NULL) {
            PyErr_SetObject((PyObject *) Py_TYPE(v), v);
            Py_DECREF(v);
        }
    }
#ifdef MS_WINDOWS
    LocalFree(s_buf);
#endif
    return NULL;
}

PyObject *
PyErr_SetFromErrnoWithFilename(PyObject *exc, const char *filename)
{
    PyObject *name = filename ? PyUnicode_DecodeFSDefault(filename) : NULL;
    PyObject *result = PyErr_SetFromErrnoWithFilenameObjects(exc, name, NULL);
    Py_XDECREF(name);
    return result;
}

#ifdef MS_WINDOWS
PyObject *
PyErr_SetFromErrnoWithUnicodeFilename(PyObject *exc, const Py_UNICODE *filename)
{
    PyObject *name = filename ?
                     PyUnicode_FromUnicode(filename, wcslen(filename)) :
             NULL;
    PyObject *result = PyErr_SetFromErrnoWithFilenameObjects(exc, name, NULL);
    Py_XDECREF(name);
    return result;
}
#endif /* MS_WINDOWS */

PyObject *
PyErr_SetFromErrno(PyObject *exc)
{
    return PyErr_SetFromErrnoWithFilenameObjects(exc, NULL, NULL);
}

#ifdef MS_WINDOWS
/* Windows specific error code handling */
PyObject *PyErr_SetExcFromWindowsErrWithFilenameObject(
    PyObject *exc,
    int ierr,
    PyObject *filenameObject)
{
    return PyErr_SetExcFromWindowsErrWithFilenameObjects(exc, ierr,
        filenameObject, NULL);
}

PyObject *PyErr_SetExcFromWindowsErrWithFilenameObjects(
    PyObject *exc,
    int ierr,
    PyObject *filenameObject,
    PyObject *filenameObject2)
{
    int len;
    WCHAR *s_buf = NULL; /* Free via LocalFree */
    PyObject *message;
    PyObject *args, *v;
    DWORD err = (DWORD)ierr;
    if (err==0) err = GetLastError();
    len = FormatMessageW(
        /* Error API error */
        FORMAT_MESSAGE_ALLOCATE_BUFFER |
        FORMAT_MESSAGE_FROM_SYSTEM |
        FORMAT_MESSAGE_IGNORE_INSERTS,
        NULL,           /* no message source */
        err,
        MAKELANGID(LANG_NEUTRAL,
        SUBLANG_DEFAULT), /* Default language */
        (LPWSTR) &s_buf,
        0,              /* size not used */
        NULL);          /* no args */
    if (len==0) {
        /* Only seen this in out of mem situations */
        message = PyUnicode_FromFormat("Windows Error 0x%x", err);
        s_buf = NULL;
    } else {
        /* remove trailing cr/lf and dots */
        while (len > 0 && (s_buf[len-1] <= L' ' || s_buf[len-1] == L'.'))
            s_buf[--len] = L'\0';
        message = PyUnicode_FromWideChar(s_buf, len);
    }

    if (message == NULL)
    {
        LocalFree(s_buf);
        return NULL;
    }

    if (filenameObject == NULL) {
        assert(filenameObject2 == NULL);
        filenameObject = filenameObject2 = Py_None;
    }
    else if (filenameObject2 == NULL)
        filenameObject2 = Py_None;
    /* This is the constructor signature for OSError.
       The POSIX translation will be figured out by the constructor. */
    args = Py_BuildValue("(iOOiO)", 0, message, filenameObject, err, filenameObject2);
    Py_DECREF(message);

    if (args != NULL) {
        v = PyObject_Call(exc, args, NULL);
        Py_DECREF(args);
        if (v != NULL) {
            PyErr_SetObject((PyObject *) Py_TYPE(v), v);
            Py_DECREF(v);
        }
    }
    LocalFree(s_buf);
    return NULL;
}

PyObject *PyErr_SetExcFromWindowsErrWithFilename(
    PyObject *exc,
    int ierr,
    const char *filename)
{
    PyObject *name = filename ? PyUnicode_DecodeFSDefault(filename) : NULL;
    PyObject *ret = PyErr_SetExcFromWindowsErrWithFilenameObjects(exc,
                                                                 ierr,
                                                                 name,
                                                                 NULL);
    Py_XDECREF(name);
    return ret;
}

PyObject *PyErr_SetExcFromWindowsErrWithUnicodeFilename(
    PyObject *exc,
    int ierr,
    const Py_UNICODE *filename)
{
    PyObject *name = filename ?
                     PyUnicode_FromUnicode(filename, wcslen(filename)) :
             NULL;
    PyObject *ret = PyErr_SetExcFromWindowsErrWithFilenameObjects(exc,
                                                                 ierr,
                                                                 name,
                                                                 NULL);
    Py_XDECREF(name);
    return ret;
}

PyObject *PyErr_SetExcFromWindowsErr(PyObject *exc, int ierr)
{
    return PyErr_SetExcFromWindowsErrWithFilename(exc, ierr, NULL);
}

PyObject *PyErr_SetFromWindowsErr(int ierr)
{
    return PyErr_SetExcFromWindowsErrWithFilename(PyExc_OSError,
                                                  ierr, NULL);
}

PyObject *PyErr_SetFromWindowsErrWithFilename(
    int ierr,
    const char *filename)
{
    PyObject *name = filename ? PyUnicode_DecodeFSDefault(filename) : NULL;
    PyObject *result = PyErr_SetExcFromWindowsErrWithFilenameObjects(
                                                  PyExc_OSError,
                                                  ierr, name, NULL);
    Py_XDECREF(name);
    return result;
}

PyObject *PyErr_SetFromWindowsErrWithUnicodeFilename(
    int ierr,
    const Py_UNICODE *filename)
{
    PyObject *name = filename ?
                     PyUnicode_FromUnicode(filename, wcslen(filename)) :
             NULL;
    PyObject *result = PyErr_SetExcFromWindowsErrWithFilenameObjects(
                                                  PyExc_OSError,
                                                  ierr, name, NULL);
    Py_XDECREF(name);
    return result;
}
#endif /* MS_WINDOWS */

PyObject *
PyErr_SetImportError(PyObject *msg, PyObject *name, PyObject *path)
{
    PyObject *args, *kwargs, *error;

    if (msg == NULL)
        return NULL;

    args = PyTuple_New(1);
    if (args == NULL)
        return NULL;

    kwargs = PyDict_New();
    if (kwargs == NULL) {
        Py_DECREF(args);
        return NULL;
    }

    if (name == NULL) {
        name = Py_None;
    }

    if (path == NULL) {
        path = Py_None;
    }

    Py_INCREF(msg);
    PyTuple_SET_ITEM(args, 0, msg);

    if (PyDict_SetItemString(kwargs, "name", name) < 0)
        return NULL;
    if (PyDict_SetItemString(kwargs, "path", path) < 0)
        return NULL;

    error = PyObject_Call(PyExc_ImportError, args, kwargs);
    if (error != NULL) {
        PyErr_SetObject((PyObject *)Py_TYPE(error), error);
        Py_DECREF(error);
    }

    Py_DECREF(args);
    Py_DECREF(kwargs);

    return NULL;
}

void
_PyErr_BadInternalCall(const char *filename, int lineno)
{
    PyErr_Format(PyExc_SystemError,
                 "%s:%d: bad argument to internal function",
                 filename, lineno);
}

/* Remove the preprocessor macro for PyErr_BadInternalCall() so that we can
   export the entry point for existing object code: */
#undef PyErr_BadInternalCall
void
PyErr_BadInternalCall(void)
{
    assert(0 && "bad argument to internal function");
    PyErr_Format(PyExc_SystemError,
                 "bad argument to internal function");
}
#define PyErr_BadInternalCall() _PyErr_BadInternalCall(__FILE__, __LINE__)


PyObject *
PyErr_FormatV(PyObject *exception, const char *format, va_list vargs)
{
    PyObject* string;

    /* Issue #23571: PyUnicode_FromFormatV() must not be called with an
       exception set, it calls arbitrary Python code like PyObject_Repr() */
    PyErr_Clear();

    string = PyUnicode_FromFormatV(format, vargs);

    PyErr_SetObject(exception, string);
    Py_XDECREF(string);
    return NULL;
}


PyObject *
PyErr_Format(PyObject *exception, const char *format, ...)
{
    va_list vargs;
#ifdef HAVE_STDARG_PROTOTYPES
    va_start(vargs, format);
#else
    va_start(vargs);
#endif
    PyErr_FormatV(exception, format, vargs);
    va_end(vargs);
    return NULL;
}


PyObject *
PyErr_NewException(const char *name, PyObject *base, PyObject *dict)
{
    const char *dot;
    PyObject *modulename = NULL;
    PyObject *classname = NULL;
    PyObject *mydict = NULL;
    PyObject *bases = NULL;
    PyObject *result = NULL;
    dot = strrchr(name, '.');
    if (dot == NULL) {
        PyErr_SetString(PyExc_SystemError,
            "PyErr_NewException: name must be module.class");
        return NULL;
    }
    if (base == NULL)
        base = PyExc_Exception;
    if (dict == NULL) {
        dict = mydict = PyDict_New();
        if (dict == NULL)
            goto failure;
    }
    if (PyDict_GetItemString(dict, "__module__") == NULL) {
        modulename = PyUnicode_FromStringAndSize(name,
                                             (Py_ssize_t)(dot-name));
        if (modulename == NULL)
            goto failure;
        if (PyDict_SetItemString(dict, "__module__", modulename) != 0)
            goto failure;
    }
    if (PyTuple_Check(base)) {
        bases = base;
        /* INCREF as we create a new ref in the else branch */
        Py_INCREF(bases);
    } else {
        bases = PyTuple_Pack(1, base);
        if (bases == NULL)
            goto failure;
    }
    /* Create a real class. */
    result = PyObject_CallFunction((PyObject *)&PyType_Type, "sOO",
                                   dot+1, bases, dict);
  failure:
    Py_XDECREF(bases);
    Py_XDECREF(mydict);
    Py_XDECREF(classname);
    Py_XDECREF(modulename);
    return result;
}


/* Create an exception with docstring */
PyObject *
PyErr_NewExceptionWithDoc(const char *name, const char *doc,
                          PyObject *base, PyObject *dict)
{
    int result;
    PyObject *ret = NULL;
    PyObject *mydict = NULL; /* points to the dict only if we create it */
    PyObject *docobj;

    if (dict == NULL) {
        dict = mydict = PyDict_New();
        if (dict == NULL) {
            return NULL;
        }
    }

    if (doc != NULL) {
        docobj = PyUnicode_FromString(doc);
        if (docobj == NULL)
            goto failure;
        result = PyDict_SetItemString(dict, "__doc__", docobj);
        Py_DECREF(docobj);
        if (result < 0)
            goto failure;
    }

    ret = PyErr_NewException(name, base, dict);
  failure:
    Py_XDECREF(mydict);
    return ret;
}


/* Call when an exception has occurred but there is no way for Python
   to handle it.  Examples: exception in __del__ or during GC. */
void
PyErr_WriteUnraisable(PyObject *obj)
{
    _Py_IDENTIFIER(__module__);
    PyObject *f, *t, *v, *tb;
    PyObject *moduleName = NULL;
    char* className;

    PyErr_Fetch(&t, &v, &tb);

    f = _PySys_GetObjectId(&PyId_stderr);
    if (f == NULL || f == Py_None)
        goto done;

    if (obj) {
        if (PyFile_WriteString("Exception ignored in: ", f) < 0)
            goto done;
        if (PyFile_WriteObject(obj, f, 0) < 0)
            goto done;
        if (PyFile_WriteString("\n", f) < 0)
            goto done;
    }

    if (PyTraceBack_Print(tb, f) < 0)
        goto done;

    if (!t)
        goto done;

    assert(PyExceptionClass_Check(t));
    className = PyExceptionClass_Name(t);
    if (className != NULL) {
        char *dot = strrchr(className, '.');
        if (dot != NULL)
            className = dot+1;
    }

    moduleName = _PyObject_GetAttrId(t, &PyId___module__);
    if (moduleName == NULL) {
        PyErr_Clear();
        if (PyFile_WriteString("<unknown>", f) < 0)
            goto done;
    }
    else {
        if (_PyUnicode_CompareWithId(moduleName, &PyId_builtins) != 0) {
            if (PyFile_WriteObject(moduleName, f, Py_PRINT_RAW) < 0)
                goto done;
            if (PyFile_WriteString(".", f) < 0)
                goto done;
        }
    }
    if (className == NULL) {
        if (PyFile_WriteString("<unknown>", f) < 0)
            goto done;
    }
    else {
        if (PyFile_WriteString(className, f) < 0)
            goto done;
    }

    if (v && v != Py_None) {
        if (PyFile_WriteString(": ", f) < 0)
            goto done;
        if (PyFile_WriteObject(v, f, Py_PRINT_RAW) < 0)
            goto done;
    }
    if (PyFile_WriteString("\n", f) < 0)
        goto done;

done:
    Py_XDECREF(moduleName);
    Py_XDECREF(t);
    Py_XDECREF(v);
    Py_XDECREF(tb);
    PyErr_Clear(); /* Just in case */
}

extern PyObject *PyModule_GetWarningsModule(void);


void
PyErr_SyntaxLocation(const char *filename, int lineno)
{
    PyErr_SyntaxLocationEx(filename, lineno, -1);
}


/* Set file and line information for the current exception.
   If the exception is not a SyntaxError, also sets additional attributes
   to make printing of exceptions believe it is a syntax error. */

void
PyErr_SyntaxLocationObject(PyObject *filename, int lineno, int col_offset)
{
    PyObject *exc, *v, *tb, *tmp;
    _Py_IDENTIFIER(filename);
    _Py_IDENTIFIER(lineno);
    _Py_IDENTIFIER(msg);
    _Py_IDENTIFIER(offset);
    _Py_IDENTIFIER(print_file_and_line);
    _Py_IDENTIFIER(text);

    /* add attributes for the line number and filename for the error */
    PyErr_Fetch(&exc, &v, &tb);
    PyErr_NormalizeException(&exc, &v, &tb);
    /* XXX check that it is, indeed, a syntax error. It might not
     * be, though. */
    tmp = PyLong_FromLong(lineno);
    if (tmp == NULL)
        PyErr_Clear();
    else {
        if (_PyObject_SetAttrId(v, &PyId_lineno, tmp))
            PyErr_Clear();
        Py_DECREF(tmp);
    }
    if (col_offset >= 0) {
        tmp = PyLong_FromLong(col_offset);
        if (tmp == NULL)
            PyErr_Clear();
        else {
            if (_PyObject_SetAttrId(v, &PyId_offset, tmp))
                PyErr_Clear();
            Py_DECREF(tmp);
        }
    }
    if (filename != NULL) {
        if (_PyObject_SetAttrId(v, &PyId_filename, filename))
            PyErr_Clear();

        tmp = PyErr_ProgramTextObject(filename, lineno);
        if (tmp) {
            if (_PyObject_SetAttrId(v, &PyId_text, tmp))
                PyErr_Clear();
            Py_DECREF(tmp);
        }
    }
    if (_PyObject_SetAttrId(v, &PyId_offset, Py_None)) {
        PyErr_Clear();
    }
    if (exc != PyExc_SyntaxError) {
        if (!_PyObject_HasAttrId(v, &PyId_msg)) {
            tmp = PyObject_Str(v);
            if (tmp) {
                if (_PyObject_SetAttrId(v, &PyId_msg, tmp))
                    PyErr_Clear();
                Py_DECREF(tmp);
            } else {
                PyErr_Clear();
            }
        }
        if (!_PyObject_HasAttrId(v, &PyId_print_file_and_line)) {
            if (_PyObject_SetAttrId(v, &PyId_print_file_and_line,
                                    Py_None))
                PyErr_Clear();
        }
    }
    PyErr_Restore(exc, v, tb);
}

void
PyErr_SyntaxLocationEx(const char *filename, int lineno, int col_offset)
{
    PyObject *fileobj;
    if (filename != NULL) {
        fileobj = PyUnicode_DecodeFSDefault(filename);
        if (fileobj == NULL)
            PyErr_Clear();
    }
    else
        fileobj = NULL;
    PyErr_SyntaxLocationObject(fileobj, lineno, col_offset);
    Py_XDECREF(fileobj);
}

/* Attempt to load the line of text that the exception refers to.  If it
   fails, it will return NULL but will not set an exception.

   XXX The functionality of this function is quite similar to the
   functionality in tb_displayline() in traceback.c. */

static PyObject *
err_programtext(FILE *fp, int lineno)
{
    int i;
    char linebuf[1000];

    if (fp == NULL)
        return NULL;
    for (i = 0; i < lineno; i++) {
        char *pLastChar = &linebuf[sizeof(linebuf) - 2];
        do {
            *pLastChar = '\0';
            if (Py_UniversalNewlineFgets(linebuf, sizeof linebuf,
                                         fp, NULL) == NULL)
                break;
            /* fgets read *something*; if it didn't get as
               far as pLastChar, it must have found a newline
               or hit the end of the file; if pLastChar is \n,
               it obviously found a newline; else we haven't
               yet seen a newline, so must continue */
        } while (*pLastChar != '\0' && *pLastChar != '\n');
    }
    fclose(fp);
    if (i == lineno) {
        char *p = linebuf;
        PyObject *res;
        while (*p == ' ' || *p == '\t' || *p == '\014')
            p++;
        res = PyUnicode_FromString(p);
        if (res == NULL)
            PyErr_Clear();
        return res;
    }
    return NULL;
}

PyObject *
PyErr_ProgramText(const char *filename, int lineno)
{
    FILE *fp;
    if (filename == NULL || *filename == '\0' || lineno <= 0)
        return NULL;
    fp = _Py_fopen(filename, "r" PY_STDIOTEXTMODE);
    return err_programtext(fp, lineno);
}

PyObject *
PyErr_ProgramTextObject(PyObject *filename, int lineno)
{
    FILE *fp;
    if (filename == NULL || lineno <= 0)
        return NULL;
    fp = _Py_fopen_obj(filename, "r" PY_STDIOTEXTMODE);
    if (fp == NULL) {
        PyErr_Clear();
        return NULL;
    }
    return err_programtext(fp, lineno);
}

#ifdef __cplusplus
}
#endif