1 /* Abstract Object Interface (many thanks to Jim Fulton) */
2
3 #include "Python.h"
4 #include <ctype.h>
5 #include "structmember.h" /* we need the offsetof() macro from there */
6 #include "longintrepr.h"
7
8 #define NEW_STYLE_NUMBER(o) PyType_HasFeature((o)->ob_type, \
9 Py_TPFLAGS_CHECKTYPES)
10
11
12 /* Shorthands to return certain errors */
13
14 static PyObject *
type_error(const char * msg,PyObject * obj)15 type_error(const char *msg, PyObject *obj)
16 {
17 PyErr_Format(PyExc_TypeError, msg, obj->ob_type->tp_name);
18 return NULL;
19 }
20
21 static PyObject *
null_error(void)22 null_error(void)
23 {
24 if (!PyErr_Occurred())
25 PyErr_SetString(PyExc_SystemError,
26 "null argument to internal routine");
27 return NULL;
28 }
29
30 /* Operations on any object */
31
32 int
PyObject_Cmp(PyObject * o1,PyObject * o2,int * result)33 PyObject_Cmp(PyObject *o1, PyObject *o2, int *result)
34 {
35 int r;
36
37 if (o1 == NULL || o2 == NULL) {
38 null_error();
39 return -1;
40 }
41 r = PyObject_Compare(o1, o2);
42 if (PyErr_Occurred())
43 return -1;
44 *result = r;
45 return 0;
46 }
47
48 PyObject *
PyObject_Type(PyObject * o)49 PyObject_Type(PyObject *o)
50 {
51 PyObject *v;
52
53 if (o == NULL)
54 return null_error();
55 v = (PyObject *)o->ob_type;
56 Py_INCREF(v);
57 return v;
58 }
59
60 Py_ssize_t
PyObject_Size(PyObject * o)61 PyObject_Size(PyObject *o)
62 {
63 PySequenceMethods *m;
64
65 if (o == NULL) {
66 null_error();
67 return -1;
68 }
69
70 m = o->ob_type->tp_as_sequence;
71 if (m && m->sq_length)
72 return m->sq_length(o);
73
74 return PyMapping_Size(o);
75 }
76
77 #undef PyObject_Length
78 Py_ssize_t
PyObject_Length(PyObject * o)79 PyObject_Length(PyObject *o)
80 {
81 return PyObject_Size(o);
82 }
83 #define PyObject_Length PyObject_Size
84
85
86 /* The length hint function returns a non-negative value from o.__len__()
87 or o.__length_hint__(). If those methods aren't found or return a negative
88 value, then the defaultvalue is returned. If one of the calls fails,
89 this function returns -1.
90 */
91
92 Py_ssize_t
_PyObject_LengthHint(PyObject * o,Py_ssize_t defaultvalue)93 _PyObject_LengthHint(PyObject *o, Py_ssize_t defaultvalue)
94 {
95 static PyObject *hintstrobj = NULL;
96 PyObject *ro, *hintmeth;
97 Py_ssize_t rv;
98
99 /* try o.__len__() */
100 rv = PyObject_Size(o);
101 if (rv >= 0)
102 return rv;
103 if (PyErr_Occurred()) {
104 if (!PyErr_ExceptionMatches(PyExc_TypeError) &&
105 !PyErr_ExceptionMatches(PyExc_AttributeError))
106 return -1;
107 PyErr_Clear();
108 }
109
110 if (PyInstance_Check(o))
111 return defaultvalue;
112 /* try o.__length_hint__() */
113 hintmeth = _PyObject_LookupSpecial(o, "__length_hint__", &hintstrobj);
114 if (hintmeth == NULL) {
115 if (PyErr_Occurred())
116 return -1;
117 else
118 return defaultvalue;
119 }
120 ro = PyObject_CallFunctionObjArgs(hintmeth, NULL);
121 Py_DECREF(hintmeth);
122 if (ro == NULL) {
123 if (!PyErr_ExceptionMatches(PyExc_TypeError) &&
124 !PyErr_ExceptionMatches(PyExc_AttributeError))
125 return -1;
126 PyErr_Clear();
127 return defaultvalue;
128 }
129 rv = PyNumber_Check(ro) ? PyInt_AsSsize_t(ro) : defaultvalue;
130 Py_DECREF(ro);
131 return rv;
132 }
133
134 PyObject *
PyObject_GetItem(PyObject * o,PyObject * key)135 PyObject_GetItem(PyObject *o, PyObject *key)
136 {
137 PyMappingMethods *m;
138
139 if (o == NULL || key == NULL)
140 return null_error();
141
142 m = o->ob_type->tp_as_mapping;
143 if (m && m->mp_subscript)
144 return m->mp_subscript(o, key);
145
146 if (o->ob_type->tp_as_sequence) {
147 if (PyIndex_Check(key)) {
148 Py_ssize_t key_value;
149 key_value = PyNumber_AsSsize_t(key, PyExc_IndexError);
150 if (key_value == -1 && PyErr_Occurred())
151 return NULL;
152 return PySequence_GetItem(o, key_value);
153 }
154 else if (o->ob_type->tp_as_sequence->sq_item)
155 return type_error("sequence index must "
156 "be integer, not '%.200s'", key);
157 }
158
159 return type_error("'%.200s' object has no attribute '__getitem__'", o);
160 }
161
162 int
PyObject_SetItem(PyObject * o,PyObject * key,PyObject * value)163 PyObject_SetItem(PyObject *o, PyObject *key, PyObject *value)
164 {
165 PyMappingMethods *m;
166
167 if (o == NULL || key == NULL || value == NULL) {
168 null_error();
169 return -1;
170 }
171 m = o->ob_type->tp_as_mapping;
172 if (m && m->mp_ass_subscript)
173 return m->mp_ass_subscript(o, key, value);
174
175 if (o->ob_type->tp_as_sequence) {
176 if (PyIndex_Check(key)) {
177 Py_ssize_t key_value;
178 key_value = PyNumber_AsSsize_t(key, PyExc_IndexError);
179 if (key_value == -1 && PyErr_Occurred())
180 return -1;
181 return PySequence_SetItem(o, key_value, value);
182 }
183 else if (o->ob_type->tp_as_sequence->sq_ass_item) {
184 type_error("sequence index must be "
185 "integer, not '%.200s'", key);
186 return -1;
187 }
188 }
189
190 type_error("'%.200s' object does not support item assignment", o);
191 return -1;
192 }
193
194 int
PyObject_DelItem(PyObject * o,PyObject * key)195 PyObject_DelItem(PyObject *o, PyObject *key)
196 {
197 PyMappingMethods *m;
198
199 if (o == NULL || key == NULL) {
200 null_error();
201 return -1;
202 }
203 m = o->ob_type->tp_as_mapping;
204 if (m && m->mp_ass_subscript)
205 return m->mp_ass_subscript(o, key, (PyObject*)NULL);
206
207 if (o->ob_type->tp_as_sequence) {
208 if (PyIndex_Check(key)) {
209 Py_ssize_t key_value;
210 key_value = PyNumber_AsSsize_t(key, PyExc_IndexError);
211 if (key_value == -1 && PyErr_Occurred())
212 return -1;
213 return PySequence_DelItem(o, key_value);
214 }
215 else if (o->ob_type->tp_as_sequence->sq_ass_item) {
216 type_error("sequence index must be "
217 "integer, not '%.200s'", key);
218 return -1;
219 }
220 }
221
222 type_error("'%.200s' object does not support item deletion", o);
223 return -1;
224 }
225
226 int
PyObject_DelItemString(PyObject * o,char * key)227 PyObject_DelItemString(PyObject *o, char *key)
228 {
229 PyObject *okey;
230 int ret;
231
232 if (o == NULL || key == NULL) {
233 null_error();
234 return -1;
235 }
236 okey = PyString_FromString(key);
237 if (okey == NULL)
238 return -1;
239 ret = PyObject_DelItem(o, okey);
240 Py_DECREF(okey);
241 return ret;
242 }
243
244 int
PyObject_AsCharBuffer(PyObject * obj,const char ** buffer,Py_ssize_t * buffer_len)245 PyObject_AsCharBuffer(PyObject *obj,
246 const char **buffer,
247 Py_ssize_t *buffer_len)
248 {
249 PyBufferProcs *pb;
250 char *pp;
251 Py_ssize_t len;
252
253 if (obj == NULL || buffer == NULL || buffer_len == NULL) {
254 null_error();
255 return -1;
256 }
257 pb = obj->ob_type->tp_as_buffer;
258 if (pb == NULL ||
259 pb->bf_getcharbuffer == NULL ||
260 pb->bf_getsegcount == NULL) {
261 PyErr_SetString(PyExc_TypeError,
262 "expected a character buffer object");
263 return -1;
264 }
265 if ((*pb->bf_getsegcount)(obj,NULL) != 1) {
266 PyErr_SetString(PyExc_TypeError,
267 "expected a single-segment buffer object");
268 return -1;
269 }
270 len = (*pb->bf_getcharbuffer)(obj, 0, &pp);
271 if (len < 0)
272 return -1;
273 *buffer = pp;
274 *buffer_len = len;
275 return 0;
276 }
277
278 int
PyObject_CheckReadBuffer(PyObject * obj)279 PyObject_CheckReadBuffer(PyObject *obj)
280 {
281 PyBufferProcs *pb = obj->ob_type->tp_as_buffer;
282
283 if (pb == NULL ||
284 pb->bf_getreadbuffer == NULL ||
285 pb->bf_getsegcount == NULL ||
286 (*pb->bf_getsegcount)(obj, NULL) != 1)
287 return 0;
288 return 1;
289 }
290
PyObject_AsReadBuffer(PyObject * obj,const void ** buffer,Py_ssize_t * buffer_len)291 int PyObject_AsReadBuffer(PyObject *obj,
292 const void **buffer,
293 Py_ssize_t *buffer_len)
294 {
295 PyBufferProcs *pb;
296 void *pp;
297 Py_ssize_t len;
298
299 if (obj == NULL || buffer == NULL || buffer_len == NULL) {
300 null_error();
301 return -1;
302 }
303 pb = obj->ob_type->tp_as_buffer;
304 if (pb == NULL ||
305 pb->bf_getreadbuffer == NULL ||
306 pb->bf_getsegcount == NULL) {
307 PyErr_SetString(PyExc_TypeError,
308 "expected a readable buffer object");
309 return -1;
310 }
311 if ((*pb->bf_getsegcount)(obj, NULL) != 1) {
312 PyErr_SetString(PyExc_TypeError,
313 "expected a single-segment buffer object");
314 return -1;
315 }
316 len = (*pb->bf_getreadbuffer)(obj, 0, &pp);
317 if (len < 0)
318 return -1;
319 *buffer = pp;
320 *buffer_len = len;
321 return 0;
322 }
323
PyObject_AsWriteBuffer(PyObject * obj,void ** buffer,Py_ssize_t * buffer_len)324 int PyObject_AsWriteBuffer(PyObject *obj,
325 void **buffer,
326 Py_ssize_t *buffer_len)
327 {
328 PyBufferProcs *pb;
329 void*pp;
330 Py_ssize_t len;
331
332 if (obj == NULL || buffer == NULL || buffer_len == NULL) {
333 null_error();
334 return -1;
335 }
336 pb = obj->ob_type->tp_as_buffer;
337 if (pb == NULL ||
338 pb->bf_getwritebuffer == NULL ||
339 pb->bf_getsegcount == NULL) {
340 PyErr_SetString(PyExc_TypeError,
341 "expected a writeable buffer object");
342 return -1;
343 }
344 if ((*pb->bf_getsegcount)(obj, NULL) != 1) {
345 PyErr_SetString(PyExc_TypeError,
346 "expected a single-segment buffer object");
347 return -1;
348 }
349 len = (*pb->bf_getwritebuffer)(obj,0,&pp);
350 if (len < 0)
351 return -1;
352 *buffer = pp;
353 *buffer_len = len;
354 return 0;
355 }
356
357 /* Buffer C-API for Python 3.0 */
358
359 int
PyObject_GetBuffer(PyObject * obj,Py_buffer * view,int flags)360 PyObject_GetBuffer(PyObject *obj, Py_buffer *view, int flags)
361 {
362 if (!PyObject_CheckBuffer(obj)) {
363 PyErr_Format(PyExc_TypeError,
364 "'%100s' does not have the buffer interface",
365 Py_TYPE(obj)->tp_name);
366 return -1;
367 }
368 return (*(obj->ob_type->tp_as_buffer->bf_getbuffer))(obj, view, flags);
369 }
370
371 static int
_IsFortranContiguous(Py_buffer * view)372 _IsFortranContiguous(Py_buffer *view)
373 {
374 Py_ssize_t sd, dim;
375 int i;
376
377 if (view->ndim == 0) return 1;
378 if (view->strides == NULL) return (view->ndim == 1);
379
380 sd = view->itemsize;
381 if (view->ndim == 1) return (view->shape[0] == 1 ||
382 sd == view->strides[0]);
383 for (i=0; i<view->ndim; i++) {
384 dim = view->shape[i];
385 if (dim == 0) return 1;
386 if (view->strides[i] != sd) return 0;
387 sd *= dim;
388 }
389 return 1;
390 }
391
392 static int
_IsCContiguous(Py_buffer * view)393 _IsCContiguous(Py_buffer *view)
394 {
395 Py_ssize_t sd, dim;
396 int i;
397
398 if (view->ndim == 0) return 1;
399 if (view->strides == NULL) return 1;
400
401 sd = view->itemsize;
402 if (view->ndim == 1) return (view->shape[0] == 1 ||
403 sd == view->strides[0]);
404 for (i=view->ndim-1; i>=0; i--) {
405 dim = view->shape[i];
406 if (dim == 0) return 1;
407 if (view->strides[i] != sd) return 0;
408 sd *= dim;
409 }
410 return 1;
411 }
412
413 int
PyBuffer_IsContiguous(Py_buffer * view,char fort)414 PyBuffer_IsContiguous(Py_buffer *view, char fort)
415 {
416
417 if (view->suboffsets != NULL) return 0;
418
419 if (fort == 'C')
420 return _IsCContiguous(view);
421 else if (fort == 'F')
422 return _IsFortranContiguous(view);
423 else if (fort == 'A')
424 return (_IsCContiguous(view) || _IsFortranContiguous(view));
425 return 0;
426 }
427
428
429 void*
PyBuffer_GetPointer(Py_buffer * view,Py_ssize_t * indices)430 PyBuffer_GetPointer(Py_buffer *view, Py_ssize_t *indices)
431 {
432 char* pointer;
433 int i;
434 pointer = (char *)view->buf;
435 for (i = 0; i < view->ndim; i++) {
436 pointer += view->strides[i]*indices[i];
437 if ((view->suboffsets != NULL) && (view->suboffsets[i] >= 0)) {
438 pointer = *((char**)pointer) + view->suboffsets[i];
439 }
440 }
441 return (void*)pointer;
442 }
443
444
445 void
_Py_add_one_to_index_F(int nd,Py_ssize_t * index,const Py_ssize_t * shape)446 _Py_add_one_to_index_F(int nd, Py_ssize_t *index, const Py_ssize_t *shape)
447 {
448 int k;
449
450 for (k=0; k<nd; k++) {
451 if (index[k] < shape[k]-1) {
452 index[k]++;
453 break;
454 }
455 else {
456 index[k] = 0;
457 }
458 }
459 }
460
461 void
_Py_add_one_to_index_C(int nd,Py_ssize_t * index,const Py_ssize_t * shape)462 _Py_add_one_to_index_C(int nd, Py_ssize_t *index, const Py_ssize_t *shape)
463 {
464 int k;
465
466 for (k=nd-1; k>=0; k--) {
467 if (index[k] < shape[k]-1) {
468 index[k]++;
469 break;
470 }
471 else {
472 index[k] = 0;
473 }
474 }
475 }
476
477 /* view is not checked for consistency in either of these. It is
478 assumed that the size of the buffer is view->len in
479 view->len / view->itemsize elements.
480 */
481
482 int
PyBuffer_ToContiguous(void * buf,Py_buffer * view,Py_ssize_t len,char fort)483 PyBuffer_ToContiguous(void *buf, Py_buffer *view, Py_ssize_t len, char fort)
484 {
485 int k;
486 void (*addone)(int, Py_ssize_t *, const Py_ssize_t *);
487 Py_ssize_t *indices, elements;
488 char *dest, *ptr;
489
490 if (len > view->len) {
491 len = view->len;
492 }
493
494 if (PyBuffer_IsContiguous(view, fort)) {
495 /* simplest copy is all that is needed */
496 memcpy(buf, view->buf, len);
497 return 0;
498 }
499
500 /* Otherwise a more elaborate scheme is needed */
501
502 /* view->ndim <= 64 */
503 indices = (Py_ssize_t *)PyMem_Malloc(sizeof(Py_ssize_t)*(view->ndim));
504 if (indices == NULL) {
505 PyErr_NoMemory();
506 return -1;
507 }
508 for (k=0; k<view->ndim;k++) {
509 indices[k] = 0;
510 }
511
512 if (fort == 'F') {
513 addone = _Py_add_one_to_index_F;
514 }
515 else {
516 addone = _Py_add_one_to_index_C;
517 }
518 dest = buf;
519 /* XXX : This is not going to be the fastest code in the world
520 several optimizations are possible.
521 */
522 elements = len / view->itemsize;
523 while (elements--) {
524 ptr = PyBuffer_GetPointer(view, indices);
525 memcpy(dest, ptr, view->itemsize);
526 dest += view->itemsize;
527 addone(view->ndim, indices, view->shape);
528 }
529 PyMem_Free(indices);
530 return 0;
531 }
532
533 int
PyBuffer_FromContiguous(Py_buffer * view,void * buf,Py_ssize_t len,char fort)534 PyBuffer_FromContiguous(Py_buffer *view, void *buf, Py_ssize_t len, char fort)
535 {
536 int k;
537 void (*addone)(int, Py_ssize_t *, const Py_ssize_t *);
538 Py_ssize_t *indices, elements;
539 char *src, *ptr;
540
541 if (len > view->len) {
542 len = view->len;
543 }
544
545 if (PyBuffer_IsContiguous(view, fort)) {
546 /* simplest copy is all that is needed */
547 memcpy(view->buf, buf, len);
548 return 0;
549 }
550
551 /* Otherwise a more elaborate scheme is needed */
552
553 /* view->ndim <= 64 */
554 indices = (Py_ssize_t *)PyMem_Malloc(sizeof(Py_ssize_t)*(view->ndim));
555 if (indices == NULL) {
556 PyErr_NoMemory();
557 return -1;
558 }
559 for (k=0; k<view->ndim;k++) {
560 indices[k] = 0;
561 }
562
563 if (fort == 'F') {
564 addone = _Py_add_one_to_index_F;
565 }
566 else {
567 addone = _Py_add_one_to_index_C;
568 }
569 src = buf;
570 /* XXX : This is not going to be the fastest code in the world
571 several optimizations are possible.
572 */
573 elements = len / view->itemsize;
574 while (elements--) {
575 ptr = PyBuffer_GetPointer(view, indices);
576 memcpy(ptr, src, view->itemsize);
577 src += view->itemsize;
578 addone(view->ndim, indices, view->shape);
579 }
580
581 PyMem_Free(indices);
582 return 0;
583 }
584
PyObject_CopyData(PyObject * dest,PyObject * src)585 int PyObject_CopyData(PyObject *dest, PyObject *src)
586 {
587 Py_buffer view_dest, view_src;
588 int k;
589 Py_ssize_t *indices, elements;
590 char *dptr, *sptr;
591
592 if (!PyObject_CheckBuffer(dest) ||
593 !PyObject_CheckBuffer(src)) {
594 PyErr_SetString(PyExc_TypeError,
595 "both destination and source must have the "\
596 "buffer interface");
597 return -1;
598 }
599
600 if (PyObject_GetBuffer(dest, &view_dest, PyBUF_FULL) != 0) return -1;
601 if (PyObject_GetBuffer(src, &view_src, PyBUF_FULL_RO) != 0) {
602 PyBuffer_Release(&view_dest);
603 return -1;
604 }
605
606 if (view_dest.len < view_src.len) {
607 PyErr_SetString(PyExc_BufferError,
608 "destination is too small to receive data from source");
609 PyBuffer_Release(&view_dest);
610 PyBuffer_Release(&view_src);
611 return -1;
612 }
613
614 if ((PyBuffer_IsContiguous(&view_dest, 'C') &&
615 PyBuffer_IsContiguous(&view_src, 'C')) ||
616 (PyBuffer_IsContiguous(&view_dest, 'F') &&
617 PyBuffer_IsContiguous(&view_src, 'F'))) {
618 /* simplest copy is all that is needed */
619 memcpy(view_dest.buf, view_src.buf, view_src.len);
620 PyBuffer_Release(&view_dest);
621 PyBuffer_Release(&view_src);
622 return 0;
623 }
624
625 /* Otherwise a more elaborate copy scheme is needed */
626
627 /* XXX(nnorwitz): need to check for overflow! */
628 indices = (Py_ssize_t *)PyMem_Malloc(sizeof(Py_ssize_t)*view_src.ndim);
629 if (indices == NULL) {
630 PyErr_NoMemory();
631 PyBuffer_Release(&view_dest);
632 PyBuffer_Release(&view_src);
633 return -1;
634 }
635 for (k=0; k<view_src.ndim;k++) {
636 indices[k] = 0;
637 }
638 elements = 1;
639 for (k=0; k<view_src.ndim; k++) {
640 /* XXX(nnorwitz): can this overflow? */
641 elements *= view_src.shape[k];
642 }
643 while (elements--) {
644 _Py_add_one_to_index_C(view_src.ndim, indices, view_src.shape);
645 dptr = PyBuffer_GetPointer(&view_dest, indices);
646 sptr = PyBuffer_GetPointer(&view_src, indices);
647 memcpy(dptr, sptr, view_src.itemsize);
648 }
649 PyMem_Free(indices);
650 PyBuffer_Release(&view_dest);
651 PyBuffer_Release(&view_src);
652 return 0;
653 }
654
655 void
PyBuffer_FillContiguousStrides(int nd,Py_ssize_t * shape,Py_ssize_t * strides,int itemsize,char fort)656 PyBuffer_FillContiguousStrides(int nd, Py_ssize_t *shape,
657 Py_ssize_t *strides, int itemsize,
658 char fort)
659 {
660 int k;
661 Py_ssize_t sd;
662
663 sd = itemsize;
664 if (fort == 'F') {
665 for (k=0; k<nd; k++) {
666 strides[k] = sd;
667 sd *= shape[k];
668 }
669 }
670 else {
671 for (k=nd-1; k>=0; k--) {
672 strides[k] = sd;
673 sd *= shape[k];
674 }
675 }
676 return;
677 }
678
679 int
PyBuffer_FillInfo(Py_buffer * view,PyObject * obj,void * buf,Py_ssize_t len,int readonly,int flags)680 PyBuffer_FillInfo(Py_buffer *view, PyObject *obj, void *buf, Py_ssize_t len,
681 int readonly, int flags)
682 {
683 if (view == NULL) return 0;
684 if (((flags & PyBUF_WRITABLE) == PyBUF_WRITABLE) &&
685 (readonly == 1)) {
686 PyErr_SetString(PyExc_BufferError,
687 "Object is not writable.");
688 return -1;
689 }
690
691 view->obj = obj;
692 if (obj)
693 Py_INCREF(obj);
694 view->buf = buf;
695 view->len = len;
696 view->readonly = readonly;
697 view->itemsize = 1;
698 view->format = NULL;
699 if ((flags & PyBUF_FORMAT) == PyBUF_FORMAT)
700 view->format = "B";
701 view->ndim = 1;
702 view->shape = NULL;
703 if ((flags & PyBUF_ND) == PyBUF_ND)
704 view->shape = &(view->len);
705 view->strides = NULL;
706 if ((flags & PyBUF_STRIDES) == PyBUF_STRIDES)
707 view->strides = &(view->itemsize);
708 view->suboffsets = NULL;
709 view->internal = NULL;
710 return 0;
711 }
712
713 void
PyBuffer_Release(Py_buffer * view)714 PyBuffer_Release(Py_buffer *view)
715 {
716 PyObject *obj = view->obj;
717 if (obj && Py_TYPE(obj)->tp_as_buffer && Py_TYPE(obj)->tp_as_buffer->bf_releasebuffer)
718 Py_TYPE(obj)->tp_as_buffer->bf_releasebuffer(obj, view);
719 Py_XDECREF(obj);
720 view->obj = NULL;
721 }
722
723 PyObject *
PyObject_Format(PyObject * obj,PyObject * format_spec)724 PyObject_Format(PyObject* obj, PyObject *format_spec)
725 {
726 PyObject *empty = NULL;
727 PyObject *result = NULL;
728 #ifdef Py_USING_UNICODE
729 int spec_is_unicode;
730 int result_is_unicode;
731 #endif
732
733 /* If no format_spec is provided, use an empty string */
734 if (format_spec == NULL) {
735 empty = PyString_FromStringAndSize(NULL, 0);
736 format_spec = empty;
737 }
738
739 /* Check the format_spec type, and make sure it's str or unicode */
740 #ifdef Py_USING_UNICODE
741 if (PyUnicode_Check(format_spec))
742 spec_is_unicode = 1;
743 else if (PyString_Check(format_spec))
744 spec_is_unicode = 0;
745 else {
746 #else
747 if (!PyString_Check(format_spec)) {
748 #endif
749 PyErr_Format(PyExc_TypeError,
750 "format expects arg 2 to be string "
751 "or unicode, not %.100s", Py_TYPE(format_spec)->tp_name);
752 goto done;
753 }
754
755 /* Check for a __format__ method and call it. */
756 if (PyInstance_Check(obj)) {
757 /* We're an instance of a classic class */
758 PyObject *bound_method = PyObject_GetAttrString(obj, "__format__");
759 if (bound_method != NULL) {
760 result = PyObject_CallFunctionObjArgs(bound_method,
761 format_spec,
762 NULL);
763 Py_DECREF(bound_method);
764 } else {
765 PyObject *self_as_str = NULL;
766 PyObject *format_method = NULL;
767 Py_ssize_t format_len;
768
769 PyErr_Clear();
770 /* Per the PEP, convert to str (or unicode,
771 depending on the type of the format
772 specifier). For new-style classes, this
773 logic is done by object.__format__(). */
774 #ifdef Py_USING_UNICODE
775 if (spec_is_unicode) {
776 format_len = PyUnicode_GET_SIZE(format_spec);
777 self_as_str = PyObject_Unicode(obj);
778 } else
779 #endif
780 {
781 format_len = PyString_GET_SIZE(format_spec);
782 self_as_str = PyObject_Str(obj);
783 }
784 if (self_as_str == NULL)
785 goto done1;
786
787 if (format_len > 0) {
788 /* See the almost identical code in
789 typeobject.c for new-style
790 classes. */
791 if (PyErr_WarnEx(
792 PyExc_PendingDeprecationWarning,
793 "object.__format__ with a non-empty "
794 "format string is deprecated", 1)
795 < 0) {
796 goto done1;
797 }
798 /* Eventually this will become an
799 error:
800 PyErr_Format(PyExc_TypeError,
801 "non-empty format string passed to "
802 "object.__format__");
803 goto done1;
804 */
805 }
806
807 /* Then call str.__format__ on that result */
808 format_method = PyObject_GetAttrString(self_as_str, "__format__");
809 if (format_method == NULL) {
810 goto done1;
811 }
812 result = PyObject_CallFunctionObjArgs(format_method,
813 format_spec,
814 NULL);
815 done1:
816 Py_XDECREF(self_as_str);
817 Py_XDECREF(format_method);
818 if (result == NULL)
819 goto done;
820 }
821 } else {
822 /* Not an instance of a classic class, use the code
823 from py3k */
824 static PyObject *format_cache = NULL;
825
826 /* Find the (unbound!) __format__ method (a borrowed
827 reference) */
828 PyObject *method = _PyObject_LookupSpecial(obj, "__format__",
829 &format_cache);
830 if (method == NULL) {
831 if (!PyErr_Occurred())
832 PyErr_Format(PyExc_TypeError,
833 "Type %.100s doesn't define __format__",
834 Py_TYPE(obj)->tp_name);
835 goto done;
836 }
837 /* And call it. */
838 result = PyObject_CallFunctionObjArgs(method, format_spec, NULL);
839 Py_DECREF(method);
840 }
841
842 if (result == NULL)
843 goto done;
844
845 /* Check the result type, and make sure it's str or unicode */
846 #ifdef Py_USING_UNICODE
847 if (PyUnicode_Check(result))
848 result_is_unicode = 1;
849 else if (PyString_Check(result))
850 result_is_unicode = 0;
851 else {
852 #else
853 if (!PyString_Check(result)) {
854 #endif
855 PyErr_Format(PyExc_TypeError,
856 "%.100s.__format__ must return string or "
857 "unicode, not %.100s", Py_TYPE(obj)->tp_name,
858 Py_TYPE(result)->tp_name);
859 Py_DECREF(result);
860 result = NULL;
861 goto done;
862 }
863
864 /* Convert to unicode, if needed. Required if spec is unicode
865 and result is str */
866 #ifdef Py_USING_UNICODE
867 if (spec_is_unicode && !result_is_unicode) {
868 PyObject *tmp = PyObject_Unicode(result);
869 /* This logic works whether or not tmp is NULL */
870 Py_DECREF(result);
871 result = tmp;
872 }
873 #endif
874
875 done:
876 Py_XDECREF(empty);
877 return result;
878 }
879
880 /* Operations on numbers */
881
882 int
883 PyNumber_Check(PyObject *o)
884 {
885 return o && o->ob_type->tp_as_number &&
886 (o->ob_type->tp_as_number->nb_int ||
887 o->ob_type->tp_as_number->nb_float);
888 }
889
890 /* Binary operators */
891
892 /* New style number protocol support */
893
894 #define NB_SLOT(x) offsetof(PyNumberMethods, x)
895 #define NB_BINOP(nb_methods, slot) \
896 (*(binaryfunc*)(& ((char*)nb_methods)[slot]))
897 #define NB_TERNOP(nb_methods, slot) \
898 (*(ternaryfunc*)(& ((char*)nb_methods)[slot]))
899
900 /*
901 Calling scheme used for binary operations:
902
903 v w Action
904 -------------------------------------------------------------------
905 new new w.op(v,w)[*], v.op(v,w), w.op(v,w)
906 new old v.op(v,w), coerce(v,w), v.op(v,w)
907 old new w.op(v,w), coerce(v,w), v.op(v,w)
908 old old coerce(v,w), v.op(v,w)
909
910 [*] only when v->ob_type != w->ob_type && w->ob_type is a subclass of
911 v->ob_type
912
913 Legend:
914 -------
915 * new == new style number
916 * old == old style number
917 * Action indicates the order in which operations are tried until either
918 a valid result is produced or an error occurs.
919
920 */
921
922 static PyObject *
923 binary_op1(PyObject *v, PyObject *w, const int op_slot)
924 {
925 PyObject *x;
926 binaryfunc slotv = NULL;
927 binaryfunc slotw = NULL;
928
929 if (v->ob_type->tp_as_number != NULL && NEW_STYLE_NUMBER(v))
930 slotv = NB_BINOP(v->ob_type->tp_as_number, op_slot);
931 if (w->ob_type != v->ob_type &&
932 w->ob_type->tp_as_number != NULL && NEW_STYLE_NUMBER(w)) {
933 slotw = NB_BINOP(w->ob_type->tp_as_number, op_slot);
934 if (slotw == slotv)
935 slotw = NULL;
936 }
937 if (slotv) {
938 if (slotw && PyType_IsSubtype(w->ob_type, v->ob_type)) {
939 x = slotw(v, w);
940 if (x != Py_NotImplemented)
941 return x;
942 Py_DECREF(x); /* can't do it */
943 slotw = NULL;
944 }
945 x = slotv(v, w);
946 if (x != Py_NotImplemented)
947 return x;
948 Py_DECREF(x); /* can't do it */
949 }
950 if (slotw) {
951 x = slotw(v, w);
952 if (x != Py_NotImplemented)
953 return x;
954 Py_DECREF(x); /* can't do it */
955 }
956 if (!NEW_STYLE_NUMBER(v) || !NEW_STYLE_NUMBER(w)) {
957 int err = PyNumber_CoerceEx(&v, &w);
958 if (err < 0) {
959 return NULL;
960 }
961 if (err == 0) {
962 PyNumberMethods *mv = v->ob_type->tp_as_number;
963 if (mv) {
964 binaryfunc slot;
965 slot = NB_BINOP(mv, op_slot);
966 if (slot) {
967 x = slot(v, w);
968 Py_DECREF(v);
969 Py_DECREF(w);
970 return x;
971 }
972 }
973 /* CoerceEx incremented the reference counts */
974 Py_DECREF(v);
975 Py_DECREF(w);
976 }
977 }
978 Py_INCREF(Py_NotImplemented);
979 return Py_NotImplemented;
980 }
981
982 static PyObject *
983 binop_type_error(PyObject *v, PyObject *w, const char *op_name)
984 {
985 PyErr_Format(PyExc_TypeError,
986 "unsupported operand type(s) for %.100s: "
987 "'%.100s' and '%.100s'",
988 op_name,
989 v->ob_type->tp_name,
990 w->ob_type->tp_name);
991 return NULL;
992 }
993
994 static PyObject *
995 binary_op(PyObject *v, PyObject *w, const int op_slot, const char *op_name)
996 {
997 PyObject *result = binary_op1(v, w, op_slot);
998 if (result == Py_NotImplemented) {
999 Py_DECREF(result);
1000 return binop_type_error(v, w, op_name);
1001 }
1002 return result;
1003 }
1004
1005
1006 /*
1007 Calling scheme used for ternary operations:
1008
1009 *** In some cases, w.op is called before v.op; see binary_op1. ***
1010
1011 v w z Action
1012 -------------------------------------------------------------------
1013 new new new v.op(v,w,z), w.op(v,w,z), z.op(v,w,z)
1014 new old new v.op(v,w,z), z.op(v,w,z), coerce(v,w,z), v.op(v,w,z)
1015 old new new w.op(v,w,z), z.op(v,w,z), coerce(v,w,z), v.op(v,w,z)
1016 old old new z.op(v,w,z), coerce(v,w,z), v.op(v,w,z)
1017 new new old v.op(v,w,z), w.op(v,w,z), coerce(v,w,z), v.op(v,w,z)
1018 new old old v.op(v,w,z), coerce(v,w,z), v.op(v,w,z)
1019 old new old w.op(v,w,z), coerce(v,w,z), v.op(v,w,z)
1020 old old old coerce(v,w,z), v.op(v,w,z)
1021
1022 Legend:
1023 -------
1024 * new == new style number
1025 * old == old style number
1026 * Action indicates the order in which operations are tried until either
1027 a valid result is produced or an error occurs.
1028 * coerce(v,w,z) actually does: coerce(v,w), coerce(v,z), coerce(w,z) and
1029 only if z != Py_None; if z == Py_None, then it is treated as absent
1030 variable and only coerce(v,w) is tried.
1031
1032 */
1033
1034 static PyObject *
1035 ternary_op(PyObject *v,
1036 PyObject *w,
1037 PyObject *z,
1038 const int op_slot,
1039 const char *op_name)
1040 {
1041 PyNumberMethods *mv, *mw, *mz;
1042 PyObject *x = NULL;
1043 ternaryfunc slotv = NULL;
1044 ternaryfunc slotw = NULL;
1045 ternaryfunc slotz = NULL;
1046
1047 mv = v->ob_type->tp_as_number;
1048 mw = w->ob_type->tp_as_number;
1049 if (mv != NULL && NEW_STYLE_NUMBER(v))
1050 slotv = NB_TERNOP(mv, op_slot);
1051 if (w->ob_type != v->ob_type &&
1052 mw != NULL && NEW_STYLE_NUMBER(w)) {
1053 slotw = NB_TERNOP(mw, op_slot);
1054 if (slotw == slotv)
1055 slotw = NULL;
1056 }
1057 if (slotv) {
1058 if (slotw && PyType_IsSubtype(w->ob_type, v->ob_type)) {
1059 x = slotw(v, w, z);
1060 if (x != Py_NotImplemented)
1061 return x;
1062 Py_DECREF(x); /* can't do it */
1063 slotw = NULL;
1064 }
1065 x = slotv(v, w, z);
1066 if (x != Py_NotImplemented)
1067 return x;
1068 Py_DECREF(x); /* can't do it */
1069 }
1070 if (slotw) {
1071 x = slotw(v, w, z);
1072 if (x != Py_NotImplemented)
1073 return x;
1074 Py_DECREF(x); /* can't do it */
1075 }
1076 mz = z->ob_type->tp_as_number;
1077 if (mz != NULL && NEW_STYLE_NUMBER(z)) {
1078 slotz = NB_TERNOP(mz, op_slot);
1079 if (slotz == slotv || slotz == slotw)
1080 slotz = NULL;
1081 if (slotz) {
1082 x = slotz(v, w, z);
1083 if (x != Py_NotImplemented)
1084 return x;
1085 Py_DECREF(x); /* can't do it */
1086 }
1087 }
1088
1089 if (!NEW_STYLE_NUMBER(v) || !NEW_STYLE_NUMBER(w) ||
1090 (z != Py_None && !NEW_STYLE_NUMBER(z))) {
1091 /* we have an old style operand, coerce */
1092 PyObject *v1, *z1, *w2, *z2;
1093 int c;
1094
1095 c = PyNumber_Coerce(&v, &w);
1096 if (c != 0)
1097 goto error3;
1098
1099 /* Special case: if the third argument is None, it is
1100 treated as absent argument and not coerced. */
1101 if (z == Py_None) {
1102 if (v->ob_type->tp_as_number) {
1103 slotz = NB_TERNOP(v->ob_type->tp_as_number,
1104 op_slot);
1105 if (slotz)
1106 x = slotz(v, w, z);
1107 else
1108 c = -1;
1109 }
1110 else
1111 c = -1;
1112 goto error2;
1113 }
1114 v1 = v;
1115 z1 = z;
1116 c = PyNumber_Coerce(&v1, &z1);
1117 if (c != 0)
1118 goto error2;
1119 w2 = w;
1120 z2 = z1;
1121 c = PyNumber_Coerce(&w2, &z2);
1122 if (c != 0)
1123 goto error1;
1124
1125 if (v1->ob_type->tp_as_number != NULL) {
1126 slotv = NB_TERNOP(v1->ob_type->tp_as_number,
1127 op_slot);
1128 if (slotv)
1129 x = slotv(v1, w2, z2);
1130 else
1131 c = -1;
1132 }
1133 else
1134 c = -1;
1135
1136 Py_DECREF(w2);
1137 Py_DECREF(z2);
1138 error1:
1139 Py_DECREF(v1);
1140 Py_DECREF(z1);
1141 error2:
1142 Py_DECREF(v);
1143 Py_DECREF(w);
1144 error3:
1145 if (c >= 0)
1146 return x;
1147 }
1148
1149 if (z == Py_None)
1150 PyErr_Format(
1151 PyExc_TypeError,
1152 "unsupported operand type(s) for ** or pow(): "
1153 "'%.100s' and '%.100s'",
1154 v->ob_type->tp_name,
1155 w->ob_type->tp_name);
1156 else
1157 PyErr_Format(
1158 PyExc_TypeError,
1159 "unsupported operand type(s) for pow(): "
1160 "'%.100s', '%.100s', '%.100s'",
1161 v->ob_type->tp_name,
1162 w->ob_type->tp_name,
1163 z->ob_type->tp_name);
1164 return NULL;
1165 }
1166
1167 #define BINARY_FUNC(func, op, op_name) \
1168 PyObject * \
1169 func(PyObject *v, PyObject *w) { \
1170 return binary_op(v, w, NB_SLOT(op), op_name); \
1171 }
1172
1173 BINARY_FUNC(PyNumber_Or, nb_or, "|")
1174 BINARY_FUNC(PyNumber_Xor, nb_xor, "^")
1175 BINARY_FUNC(PyNumber_And, nb_and, "&")
1176 BINARY_FUNC(PyNumber_Lshift, nb_lshift, "<<")
1177 BINARY_FUNC(PyNumber_Rshift, nb_rshift, ">>")
1178 BINARY_FUNC(PyNumber_Subtract, nb_subtract, "-")
1179 BINARY_FUNC(PyNumber_Divide, nb_divide, "/")
1180 BINARY_FUNC(PyNumber_Divmod, nb_divmod, "divmod()")
1181
1182 PyObject *
1183 PyNumber_Add(PyObject *v, PyObject *w)
1184 {
1185 PyObject *result = binary_op1(v, w, NB_SLOT(nb_add));
1186 if (result == Py_NotImplemented) {
1187 PySequenceMethods *m = v->ob_type->tp_as_sequence;
1188 Py_DECREF(result);
1189 if (m && m->sq_concat) {
1190 return (*m->sq_concat)(v, w);
1191 }
1192 result = binop_type_error(v, w, "+");
1193 }
1194 return result;
1195 }
1196
1197 static PyObject *
1198 sequence_repeat(ssizeargfunc repeatfunc, PyObject *seq, PyObject *n)
1199 {
1200 Py_ssize_t count;
1201 if (PyIndex_Check(n)) {
1202 count = PyNumber_AsSsize_t(n, PyExc_OverflowError);
1203 if (count == -1 && PyErr_Occurred())
1204 return NULL;
1205 }
1206 else {
1207 return type_error("can't multiply sequence by "
1208 "non-int of type '%.200s'", n);
1209 }
1210 return (*repeatfunc)(seq, count);
1211 }
1212
1213 PyObject *
1214 PyNumber_Multiply(PyObject *v, PyObject *w)
1215 {
1216 PyObject *result = binary_op1(v, w, NB_SLOT(nb_multiply));
1217 if (result == Py_NotImplemented) {
1218 PySequenceMethods *mv = v->ob_type->tp_as_sequence;
1219 PySequenceMethods *mw = w->ob_type->tp_as_sequence;
1220 Py_DECREF(result);
1221 if (mv && mv->sq_repeat) {
1222 return sequence_repeat(mv->sq_repeat, v, w);
1223 }
1224 else if (mw && mw->sq_repeat) {
1225 return sequence_repeat(mw->sq_repeat, w, v);
1226 }
1227 result = binop_type_error(v, w, "*");
1228 }
1229 return result;
1230 }
1231
1232 PyObject *
1233 PyNumber_FloorDivide(PyObject *v, PyObject *w)
1234 {
1235 /* XXX tp_flags test */
1236 return binary_op(v, w, NB_SLOT(nb_floor_divide), "//");
1237 }
1238
1239 PyObject *
1240 PyNumber_TrueDivide(PyObject *v, PyObject *w)
1241 {
1242 /* XXX tp_flags test */
1243 return binary_op(v, w, NB_SLOT(nb_true_divide), "/");
1244 }
1245
1246 PyObject *
1247 PyNumber_Remainder(PyObject *v, PyObject *w)
1248 {
1249 return binary_op(v, w, NB_SLOT(nb_remainder), "%");
1250 }
1251
1252 PyObject *
1253 PyNumber_Power(PyObject *v, PyObject *w, PyObject *z)
1254 {
1255 return ternary_op(v, w, z, NB_SLOT(nb_power), "** or pow()");
1256 }
1257
1258 /* Binary in-place operators */
1259
1260 /* The in-place operators are defined to fall back to the 'normal',
1261 non in-place operations, if the in-place methods are not in place.
1262
1263 - If the left hand object has the appropriate struct members, and
1264 they are filled, call the appropriate function and return the
1265 result. No coercion is done on the arguments; the left-hand object
1266 is the one the operation is performed on, and it's up to the
1267 function to deal with the right-hand object.
1268
1269 - Otherwise, in-place modification is not supported. Handle it exactly as
1270 a non in-place operation of the same kind.
1271
1272 */
1273
1274 #define HASINPLACE(t) \
1275 PyType_HasFeature((t)->ob_type, Py_TPFLAGS_HAVE_INPLACEOPS)
1276
1277 static PyObject *
1278 binary_iop1(PyObject *v, PyObject *w, const int iop_slot, const int op_slot)
1279 {
1280 PyNumberMethods *mv = v->ob_type->tp_as_number;
1281 if (mv != NULL && HASINPLACE(v)) {
1282 binaryfunc slot = NB_BINOP(mv, iop_slot);
1283 if (slot) {
1284 PyObject *x = (slot)(v, w);
1285 if (x != Py_NotImplemented) {
1286 return x;
1287 }
1288 Py_DECREF(x);
1289 }
1290 }
1291 return binary_op1(v, w, op_slot);
1292 }
1293
1294 static PyObject *
1295 binary_iop(PyObject *v, PyObject *w, const int iop_slot, const int op_slot,
1296 const char *op_name)
1297 {
1298 PyObject *result = binary_iop1(v, w, iop_slot, op_slot);
1299 if (result == Py_NotImplemented) {
1300 Py_DECREF(result);
1301 return binop_type_error(v, w, op_name);
1302 }
1303 return result;
1304 }
1305
1306 #define INPLACE_BINOP(func, iop, op, op_name) \
1307 PyObject * \
1308 func(PyObject *v, PyObject *w) { \
1309 return binary_iop(v, w, NB_SLOT(iop), NB_SLOT(op), op_name); \
1310 }
1311
1312 INPLACE_BINOP(PyNumber_InPlaceOr, nb_inplace_or, nb_or, "|=")
1313 INPLACE_BINOP(PyNumber_InPlaceXor, nb_inplace_xor, nb_xor, "^=")
1314 INPLACE_BINOP(PyNumber_InPlaceAnd, nb_inplace_and, nb_and, "&=")
1315 INPLACE_BINOP(PyNumber_InPlaceLshift, nb_inplace_lshift, nb_lshift, "<<=")
1316 INPLACE_BINOP(PyNumber_InPlaceRshift, nb_inplace_rshift, nb_rshift, ">>=")
1317 INPLACE_BINOP(PyNumber_InPlaceSubtract, nb_inplace_subtract, nb_subtract, "-=")
1318 INPLACE_BINOP(PyNumber_InPlaceDivide, nb_inplace_divide, nb_divide, "/=")
1319
1320 PyObject *
1321 PyNumber_InPlaceFloorDivide(PyObject *v, PyObject *w)
1322 {
1323 /* XXX tp_flags test */
1324 return binary_iop(v, w, NB_SLOT(nb_inplace_floor_divide),
1325 NB_SLOT(nb_floor_divide), "//=");
1326 }
1327
1328 PyObject *
1329 PyNumber_InPlaceTrueDivide(PyObject *v, PyObject *w)
1330 {
1331 /* XXX tp_flags test */
1332 return binary_iop(v, w, NB_SLOT(nb_inplace_true_divide),
1333 NB_SLOT(nb_true_divide), "/=");
1334 }
1335
1336 PyObject *
1337 PyNumber_InPlaceAdd(PyObject *v, PyObject *w)
1338 {
1339 PyObject *result = binary_iop1(v, w, NB_SLOT(nb_inplace_add),
1340 NB_SLOT(nb_add));
1341 if (result == Py_NotImplemented) {
1342 PySequenceMethods *m = v->ob_type->tp_as_sequence;
1343 Py_DECREF(result);
1344 if (m != NULL) {
1345 binaryfunc f = NULL;
1346 if (HASINPLACE(v))
1347 f = m->sq_inplace_concat;
1348 if (f == NULL)
1349 f = m->sq_concat;
1350 if (f != NULL)
1351 return (*f)(v, w);
1352 }
1353 result = binop_type_error(v, w, "+=");
1354 }
1355 return result;
1356 }
1357
1358 PyObject *
1359 PyNumber_InPlaceMultiply(PyObject *v, PyObject *w)
1360 {
1361 PyObject *result = binary_iop1(v, w, NB_SLOT(nb_inplace_multiply),
1362 NB_SLOT(nb_multiply));
1363 if (result == Py_NotImplemented) {
1364 ssizeargfunc f = NULL;
1365 PySequenceMethods *mv = v->ob_type->tp_as_sequence;
1366 PySequenceMethods *mw = w->ob_type->tp_as_sequence;
1367 Py_DECREF(result);
1368 if (mv != NULL) {
1369 if (HASINPLACE(v))
1370 f = mv->sq_inplace_repeat;
1371 if (f == NULL)
1372 f = mv->sq_repeat;
1373 if (f != NULL)
1374 return sequence_repeat(f, v, w);
1375 }
1376 else if (mw != NULL) {
1377 /* Note that the right hand operand should not be
1378 * mutated in this case so sq_inplace_repeat is not
1379 * used. */
1380 if (mw->sq_repeat)
1381 return sequence_repeat(mw->sq_repeat, w, v);
1382 }
1383 result = binop_type_error(v, w, "*=");
1384 }
1385 return result;
1386 }
1387
1388 PyObject *
1389 PyNumber_InPlaceRemainder(PyObject *v, PyObject *w)
1390 {
1391 return binary_iop(v, w, NB_SLOT(nb_inplace_remainder),
1392 NB_SLOT(nb_remainder), "%=");
1393 }
1394
1395 PyObject *
1396 PyNumber_InPlacePower(PyObject *v, PyObject *w, PyObject *z)
1397 {
1398 if (HASINPLACE(v) && v->ob_type->tp_as_number &&
1399 v->ob_type->tp_as_number->nb_inplace_power != NULL) {
1400 return ternary_op(v, w, z, NB_SLOT(nb_inplace_power), "**=");
1401 }
1402 else {
1403 return ternary_op(v, w, z, NB_SLOT(nb_power), "**=");
1404 }
1405 }
1406
1407
1408 /* Unary operators and functions */
1409
1410 PyObject *
1411 PyNumber_Negative(PyObject *o)
1412 {
1413 PyNumberMethods *m;
1414
1415 if (o == NULL)
1416 return null_error();
1417 m = o->ob_type->tp_as_number;
1418 if (m && m->nb_negative)
1419 return (*m->nb_negative)(o);
1420
1421 return type_error("bad operand type for unary -: '%.200s'", o);
1422 }
1423
1424 PyObject *
1425 PyNumber_Positive(PyObject *o)
1426 {
1427 PyNumberMethods *m;
1428
1429 if (o == NULL)
1430 return null_error();
1431 m = o->ob_type->tp_as_number;
1432 if (m && m->nb_positive)
1433 return (*m->nb_positive)(o);
1434
1435 return type_error("bad operand type for unary +: '%.200s'", o);
1436 }
1437
1438 PyObject *
1439 PyNumber_Invert(PyObject *o)
1440 {
1441 PyNumberMethods *m;
1442
1443 if (o == NULL)
1444 return null_error();
1445 m = o->ob_type->tp_as_number;
1446 if (m && m->nb_invert)
1447 return (*m->nb_invert)(o);
1448
1449 return type_error("bad operand type for unary ~: '%.200s'", o);
1450 }
1451
1452 PyObject *
1453 PyNumber_Absolute(PyObject *o)
1454 {
1455 PyNumberMethods *m;
1456
1457 if (o == NULL)
1458 return null_error();
1459 m = o->ob_type->tp_as_number;
1460 if (m && m->nb_absolute)
1461 return m->nb_absolute(o);
1462
1463 return type_error("bad operand type for abs(): '%.200s'", o);
1464 }
1465
1466 /* Add a check for embedded NULL-bytes in the argument. */
1467 static PyObject *
1468 int_from_string(const char *s, Py_ssize_t len)
1469 {
1470 char *end;
1471 PyObject *x;
1472
1473 x = PyInt_FromString((char*)s, &end, 10);
1474 if (x == NULL)
1475 return NULL;
1476 if (end != s + len) {
1477 PyErr_SetString(PyExc_ValueError,
1478 "null byte in argument for int()");
1479 Py_DECREF(x);
1480 return NULL;
1481 }
1482 return x;
1483 }
1484
1485 /* Return a Python Int or Long from the object item
1486 Raise TypeError if the result is not an int-or-long
1487 or if the object cannot be interpreted as an index.
1488 */
1489 PyObject *
1490 PyNumber_Index(PyObject *item)
1491 {
1492 PyObject *result = NULL;
1493 if (item == NULL)
1494 return null_error();
1495 if (PyInt_Check(item) || PyLong_Check(item)) {
1496 Py_INCREF(item);
1497 return item;
1498 }
1499 if (PyIndex_Check(item)) {
1500 result = item->ob_type->tp_as_number->nb_index(item);
1501 if (result &&
1502 !PyInt_Check(result) && !PyLong_Check(result)) {
1503 PyErr_Format(PyExc_TypeError,
1504 "__index__ returned non-(int,long) " \
1505 "(type %.200s)",
1506 result->ob_type->tp_name);
1507 Py_DECREF(result);
1508 return NULL;
1509 }
1510 }
1511 else {
1512 PyErr_Format(PyExc_TypeError,
1513 "'%.200s' object cannot be interpreted "
1514 "as an index", item->ob_type->tp_name);
1515 }
1516 return result;
1517 }
1518
1519 /* Return an error on Overflow only if err is not NULL*/
1520
1521 Py_ssize_t
1522 PyNumber_AsSsize_t(PyObject *item, PyObject *err)
1523 {
1524 Py_ssize_t result;
1525 PyObject *runerr;
1526 PyObject *value = PyNumber_Index(item);
1527 if (value == NULL)
1528 return -1;
1529
1530 /* We're done if PyInt_AsSsize_t() returns without error. */
1531 result = PyInt_AsSsize_t(value);
1532 if (result != -1 || !(runerr = PyErr_Occurred()))
1533 goto finish;
1534
1535 /* Error handling code -- only manage OverflowError differently */
1536 if (!PyErr_GivenExceptionMatches(runerr, PyExc_OverflowError))
1537 goto finish;
1538
1539 PyErr_Clear();
1540 /* If no error-handling desired then the default clipping
1541 is sufficient.
1542 */
1543 if (!err) {
1544 assert(PyLong_Check(value));
1545 /* Whether or not it is less than or equal to
1546 zero is determined by the sign of ob_size
1547 */
1548 if (_PyLong_Sign(value) < 0)
1549 result = PY_SSIZE_T_MIN;
1550 else
1551 result = PY_SSIZE_T_MAX;
1552 }
1553 else {
1554 /* Otherwise replace the error with caller's error object. */
1555 PyErr_Format(err,
1556 "cannot fit '%.200s' into an index-sized integer",
1557 item->ob_type->tp_name);
1558 }
1559
1560 finish:
1561 Py_DECREF(value);
1562 return result;
1563 }
1564
1565
1566 PyObject *
1567 _PyNumber_ConvertIntegralToInt(PyObject *integral, const char* error_format)
1568 {
1569 const char *type_name;
1570 static PyObject *int_name = NULL;
1571 if (int_name == NULL) {
1572 int_name = PyString_InternFromString("__int__");
1573 if (int_name == NULL)
1574 return NULL;
1575 }
1576
1577 if (integral && (!PyInt_Check(integral) &&
1578 !PyLong_Check(integral))) {
1579 /* Don't go through tp_as_number->nb_int to avoid
1580 hitting the classic class fallback to __trunc__. */
1581 PyObject *int_func = PyObject_GetAttr(integral, int_name);
1582 if (int_func == NULL) {
1583 PyErr_Clear(); /* Raise a different error. */
1584 goto non_integral_error;
1585 }
1586 Py_DECREF(integral);
1587 integral = PyEval_CallObject(int_func, NULL);
1588 Py_DECREF(int_func);
1589 if (integral && (!PyInt_Check(integral) &&
1590 !PyLong_Check(integral))) {
1591 goto non_integral_error;
1592 }
1593 }
1594 return integral;
1595
1596 non_integral_error:
1597 if (PyInstance_Check(integral)) {
1598 type_name = PyString_AS_STRING(((PyInstanceObject *)integral)
1599 ->in_class->cl_name);
1600 }
1601 else {
1602 type_name = integral->ob_type->tp_name;
1603 }
1604 PyErr_Format(PyExc_TypeError, error_format, type_name);
1605 Py_DECREF(integral);
1606 return NULL;
1607 }
1608
1609
1610 PyObject *
1611 PyNumber_Int(PyObject *o)
1612 {
1613 PyNumberMethods *m;
1614 static PyObject *trunc_name = NULL;
1615 PyObject *trunc_func;
1616 const char *buffer;
1617 Py_ssize_t buffer_len;
1618
1619 if (trunc_name == NULL) {
1620 trunc_name = PyString_InternFromString("__trunc__");
1621 if (trunc_name == NULL)
1622 return NULL;
1623 }
1624
1625 if (o == NULL)
1626 return null_error();
1627 if (PyInt_CheckExact(o)) {
1628 Py_INCREF(o);
1629 return o;
1630 }
1631 m = o->ob_type->tp_as_number;
1632 if (m && m->nb_int) { /* This should include subclasses of int */
1633 /* Classic classes always take this branch. */
1634 PyObject *res = m->nb_int(o);
1635 if (res && (!PyInt_Check(res) && !PyLong_Check(res))) {
1636 PyErr_Format(PyExc_TypeError,
1637 "__int__ returned non-int (type %.200s)",
1638 res->ob_type->tp_name);
1639 Py_DECREF(res);
1640 return NULL;
1641 }
1642 return res;
1643 }
1644 if (PyInt_Check(o)) { /* A int subclass without nb_int */
1645 PyIntObject *io = (PyIntObject*)o;
1646 return PyInt_FromLong(io->ob_ival);
1647 }
1648 trunc_func = PyObject_GetAttr(o, trunc_name);
1649 if (trunc_func) {
1650 PyObject *truncated = PyEval_CallObject(trunc_func, NULL);
1651 Py_DECREF(trunc_func);
1652 /* __trunc__ is specified to return an Integral type, but
1653 int() needs to return an int. */
1654 return _PyNumber_ConvertIntegralToInt(
1655 truncated,
1656 "__trunc__ returned non-Integral (type %.200s)");
1657 }
1658 PyErr_Clear(); /* It's not an error if o.__trunc__ doesn't exist. */
1659
1660 if (PyString_Check(o))
1661 return int_from_string(PyString_AS_STRING(o),
1662 PyString_GET_SIZE(o));
1663 #ifdef Py_USING_UNICODE
1664 if (PyUnicode_Check(o))
1665 return PyInt_FromUnicode(PyUnicode_AS_UNICODE(o),
1666 PyUnicode_GET_SIZE(o),
1667 10);
1668 #endif
1669 if (!PyObject_AsCharBuffer(o, &buffer, &buffer_len))
1670 return int_from_string((char*)buffer, buffer_len);
1671
1672 return type_error("int() argument must be a string or a "
1673 "number, not '%.200s'", o);
1674 }
1675
1676 /* Add a check for embedded NULL-bytes in the argument. */
1677 static PyObject *
1678 long_from_string(const char *s, Py_ssize_t len)
1679 {
1680 char *end;
1681 PyObject *x;
1682
1683 x = PyLong_FromString((char*)s, &end, 10);
1684 if (x == NULL)
1685 return NULL;
1686 if (end != s + len) {
1687 PyErr_SetString(PyExc_ValueError,
1688 "null byte in argument for long()");
1689 Py_DECREF(x);
1690 return NULL;
1691 }
1692 return x;
1693 }
1694
1695 PyObject *
1696 PyNumber_Long(PyObject *o)
1697 {
1698 PyNumberMethods *m;
1699 static PyObject *trunc_name = NULL;
1700 PyObject *trunc_func;
1701 const char *buffer;
1702 Py_ssize_t buffer_len;
1703
1704 if (trunc_name == NULL) {
1705 trunc_name = PyString_InternFromString("__trunc__");
1706 if (trunc_name == NULL)
1707 return NULL;
1708 }
1709
1710 if (o == NULL)
1711 return null_error();
1712 m = o->ob_type->tp_as_number;
1713 if (m && m->nb_long) { /* This should include subclasses of long */
1714 /* Classic classes always take this branch. */
1715 PyObject *res = m->nb_long(o);
1716 if (res == NULL)
1717 return NULL;
1718 if (PyInt_Check(res)) {
1719 long value = PyInt_AS_LONG(res);
1720 Py_DECREF(res);
1721 return PyLong_FromLong(value);
1722 }
1723 else if (!PyLong_Check(res)) {
1724 PyErr_Format(PyExc_TypeError,
1725 "__long__ returned non-long (type %.200s)",
1726 res->ob_type->tp_name);
1727 Py_DECREF(res);
1728 return NULL;
1729 }
1730 return res;
1731 }
1732 if (PyLong_Check(o)) /* A long subclass without nb_long */
1733 return _PyLong_Copy((PyLongObject *)o);
1734 trunc_func = PyObject_GetAttr(o, trunc_name);
1735 if (trunc_func) {
1736 PyObject *truncated = PyEval_CallObject(trunc_func, NULL);
1737 PyObject *int_instance;
1738 Py_DECREF(trunc_func);
1739 /* __trunc__ is specified to return an Integral type,
1740 but long() needs to return a long. */
1741 int_instance = _PyNumber_ConvertIntegralToInt(
1742 truncated,
1743 "__trunc__ returned non-Integral (type %.200s)");
1744 if (int_instance && PyInt_Check(int_instance)) {
1745 /* Make sure that long() returns a long instance. */
1746 long value = PyInt_AS_LONG(int_instance);
1747 Py_DECREF(int_instance);
1748 return PyLong_FromLong(value);
1749 }
1750 return int_instance;
1751 }
1752 PyErr_Clear(); /* It's not an error if o.__trunc__ doesn't exist. */
1753
1754 if (PyString_Check(o))
1755 /* need to do extra error checking that PyLong_FromString()
1756 * doesn't do. In particular long('9.5') must raise an
1757 * exception, not truncate the float.
1758 */
1759 return long_from_string(PyString_AS_STRING(o),
1760 PyString_GET_SIZE(o));
1761 #ifdef Py_USING_UNICODE
1762 if (PyUnicode_Check(o))
1763 /* The above check is done in PyLong_FromUnicode(). */
1764 return PyLong_FromUnicode(PyUnicode_AS_UNICODE(o),
1765 PyUnicode_GET_SIZE(o),
1766 10);
1767 #endif
1768 if (!PyObject_AsCharBuffer(o, &buffer, &buffer_len))
1769 return long_from_string(buffer, buffer_len);
1770
1771 return type_error("long() argument must be a string or a "
1772 "number, not '%.200s'", o);
1773 }
1774
1775 PyObject *
1776 PyNumber_Float(PyObject *o)
1777 {
1778 PyNumberMethods *m;
1779
1780 if (o == NULL)
1781 return null_error();
1782 m = o->ob_type->tp_as_number;
1783 if (m && m->nb_float) { /* This should include subclasses of float */
1784 PyObject *res = m->nb_float(o);
1785 if (res && !PyFloat_Check(res)) {
1786 PyErr_Format(PyExc_TypeError,
1787 "__float__ returned non-float (type %.200s)",
1788 res->ob_type->tp_name);
1789 Py_DECREF(res);
1790 return NULL;
1791 }
1792 return res;
1793 }
1794 if (PyFloat_Check(o)) { /* A float subclass with nb_float == NULL */
1795 PyFloatObject *po = (PyFloatObject *)o;
1796 return PyFloat_FromDouble(po->ob_fval);
1797 }
1798 return PyFloat_FromString(o, NULL);
1799 }
1800
1801 PyObject *
1802 PyNumber_ToBase(PyObject *n, int base)
1803 {
1804 PyObject *res = NULL;
1805 PyObject *index = PyNumber_Index(n);
1806
1807 if (!index)
1808 return NULL;
1809 if (PyLong_Check(index))
1810 res = _PyLong_Format(index, base, 0, 1);
1811 else if (PyInt_Check(index))
1812 res = _PyInt_Format((PyIntObject*)index, base, 1);
1813 else
1814 /* It should not be possible to get here, as
1815 PyNumber_Index already has a check for the same
1816 condition */
1817 PyErr_SetString(PyExc_ValueError, "PyNumber_ToBase: index not "
1818 "int or long");
1819 Py_DECREF(index);
1820 return res;
1821 }
1822
1823
1824 /* Operations on sequences */
1825
1826 int
1827 PySequence_Check(PyObject *s)
1828 {
1829 if (s == NULL)
1830 return 0;
1831 if (PyInstance_Check(s))
1832 return PyObject_HasAttrString(s, "__getitem__");
1833 if (PyDict_Check(s))
1834 return 0;
1835 return s->ob_type->tp_as_sequence &&
1836 s->ob_type->tp_as_sequence->sq_item != NULL;
1837 }
1838
1839 Py_ssize_t
1840 PySequence_Size(PyObject *s)
1841 {
1842 PySequenceMethods *m;
1843
1844 if (s == NULL) {
1845 null_error();
1846 return -1;
1847 }
1848
1849 m = s->ob_type->tp_as_sequence;
1850 if (m && m->sq_length)
1851 return m->sq_length(s);
1852
1853 type_error("object of type '%.200s' has no len()", s);
1854 return -1;
1855 }
1856
1857 #undef PySequence_Length
1858 Py_ssize_t
1859 PySequence_Length(PyObject *s)
1860 {
1861 return PySequence_Size(s);
1862 }
1863 #define PySequence_Length PySequence_Size
1864
1865 PyObject *
1866 PySequence_Concat(PyObject *s, PyObject *o)
1867 {
1868 PySequenceMethods *m;
1869
1870 if (s == NULL || o == NULL)
1871 return null_error();
1872
1873 m = s->ob_type->tp_as_sequence;
1874 if (m && m->sq_concat)
1875 return m->sq_concat(s, o);
1876
1877 /* Instances of user classes defining an __add__() method only
1878 have an nb_add slot, not an sq_concat slot. So we fall back
1879 to nb_add if both arguments appear to be sequences. */
1880 if (PySequence_Check(s) && PySequence_Check(o)) {
1881 PyObject *result = binary_op1(s, o, NB_SLOT(nb_add));
1882 if (result != Py_NotImplemented)
1883 return result;
1884 Py_DECREF(result);
1885 }
1886 return type_error("'%.200s' object can't be concatenated", s);
1887 }
1888
1889 PyObject *
1890 PySequence_Repeat(PyObject *o, Py_ssize_t count)
1891 {
1892 PySequenceMethods *m;
1893
1894 if (o == NULL)
1895 return null_error();
1896
1897 m = o->ob_type->tp_as_sequence;
1898 if (m && m->sq_repeat)
1899 return m->sq_repeat(o, count);
1900
1901 /* Instances of user classes defining a __mul__() method only
1902 have an nb_multiply slot, not an sq_repeat slot. so we fall back
1903 to nb_multiply if o appears to be a sequence. */
1904 if (PySequence_Check(o)) {
1905 PyObject *n, *result;
1906 n = PyInt_FromSsize_t(count);
1907 if (n == NULL)
1908 return NULL;
1909 result = binary_op1(o, n, NB_SLOT(nb_multiply));
1910 Py_DECREF(n);
1911 if (result != Py_NotImplemented)
1912 return result;
1913 Py_DECREF(result);
1914 }
1915 return type_error("'%.200s' object can't be repeated", o);
1916 }
1917
1918 PyObject *
1919 PySequence_InPlaceConcat(PyObject *s, PyObject *o)
1920 {
1921 PySequenceMethods *m;
1922
1923 if (s == NULL || o == NULL)
1924 return null_error();
1925
1926 m = s->ob_type->tp_as_sequence;
1927 if (m && HASINPLACE(s) && m->sq_inplace_concat)
1928 return m->sq_inplace_concat(s, o);
1929 if (m && m->sq_concat)
1930 return m->sq_concat(s, o);
1931
1932 if (PySequence_Check(s) && PySequence_Check(o)) {
1933 PyObject *result = binary_iop1(s, o, NB_SLOT(nb_inplace_add),
1934 NB_SLOT(nb_add));
1935 if (result != Py_NotImplemented)
1936 return result;
1937 Py_DECREF(result);
1938 }
1939 return type_error("'%.200s' object can't be concatenated", s);
1940 }
1941
1942 PyObject *
1943 PySequence_InPlaceRepeat(PyObject *o, Py_ssize_t count)
1944 {
1945 PySequenceMethods *m;
1946
1947 if (o == NULL)
1948 return null_error();
1949
1950 m = o->ob_type->tp_as_sequence;
1951 if (m && HASINPLACE(o) && m->sq_inplace_repeat)
1952 return m->sq_inplace_repeat(o, count);
1953 if (m && m->sq_repeat)
1954 return m->sq_repeat(o, count);
1955
1956 if (PySequence_Check(o)) {
1957 PyObject *n, *result;
1958 n = PyInt_FromSsize_t(count);
1959 if (n == NULL)
1960 return NULL;
1961 result = binary_iop1(o, n, NB_SLOT(nb_inplace_multiply),
1962 NB_SLOT(nb_multiply));
1963 Py_DECREF(n);
1964 if (result != Py_NotImplemented)
1965 return result;
1966 Py_DECREF(result);
1967 }
1968 return type_error("'%.200s' object can't be repeated", o);
1969 }
1970
1971 PyObject *
1972 PySequence_GetItem(PyObject *s, Py_ssize_t i)
1973 {
1974 PySequenceMethods *m;
1975
1976 if (s == NULL)
1977 return null_error();
1978
1979 m = s->ob_type->tp_as_sequence;
1980 if (m && m->sq_item) {
1981 if (i < 0) {
1982 if (m->sq_length) {
1983 Py_ssize_t l = (*m->sq_length)(s);
1984 if (l < 0)
1985 return NULL;
1986 i += l;
1987 }
1988 }
1989 return m->sq_item(s, i);
1990 }
1991
1992 return type_error("'%.200s' object does not support indexing", s);
1993 }
1994
1995 PyObject *
1996 PySequence_GetSlice(PyObject *s, Py_ssize_t i1, Py_ssize_t i2)
1997 {
1998 PySequenceMethods *m;
1999 PyMappingMethods *mp;
2000
2001 if (!s) return null_error();
2002
2003 m = s->ob_type->tp_as_sequence;
2004 if (m && m->sq_slice) {
2005 if (i1 < 0 || i2 < 0) {
2006 if (m->sq_length) {
2007 Py_ssize_t l = (*m->sq_length)(s);
2008 if (l < 0)
2009 return NULL;
2010 if (i1 < 0)
2011 i1 += l;
2012 if (i2 < 0)
2013 i2 += l;
2014 }
2015 }
2016 return m->sq_slice(s, i1, i2);
2017 } else if ((mp = s->ob_type->tp_as_mapping) && mp->mp_subscript) {
2018 PyObject *res;
2019 PyObject *slice = _PySlice_FromIndices(i1, i2);
2020 if (!slice)
2021 return NULL;
2022 res = mp->mp_subscript(s, slice);
2023 Py_DECREF(slice);
2024 return res;
2025 }
2026
2027 return type_error("'%.200s' object is unsliceable", s);
2028 }
2029
2030 int
2031 PySequence_SetItem(PyObject *s, Py_ssize_t i, PyObject *o)
2032 {
2033 PySequenceMethods *m;
2034
2035 if (s == NULL) {
2036 null_error();
2037 return -1;
2038 }
2039
2040 m = s->ob_type->tp_as_sequence;
2041 if (m && m->sq_ass_item) {
2042 if (i < 0) {
2043 if (m->sq_length) {
2044 Py_ssize_t l = (*m->sq_length)(s);
2045 if (l < 0)
2046 return -1;
2047 i += l;
2048 }
2049 }
2050 return m->sq_ass_item(s, i, o);
2051 }
2052
2053 type_error("'%.200s' object does not support item assignment", s);
2054 return -1;
2055 }
2056
2057 int
2058 PySequence_DelItem(PyObject *s, Py_ssize_t i)
2059 {
2060 PySequenceMethods *m;
2061
2062 if (s == NULL) {
2063 null_error();
2064 return -1;
2065 }
2066
2067 m = s->ob_type->tp_as_sequence;
2068 if (m && m->sq_ass_item) {
2069 if (i < 0) {
2070 if (m->sq_length) {
2071 Py_ssize_t l = (*m->sq_length)(s);
2072 if (l < 0)
2073 return -1;
2074 i += l;
2075 }
2076 }
2077 return m->sq_ass_item(s, i, (PyObject *)NULL);
2078 }
2079
2080 type_error("'%.200s' object doesn't support item deletion", s);
2081 return -1;
2082 }
2083
2084 int
2085 PySequence_SetSlice(PyObject *s, Py_ssize_t i1, Py_ssize_t i2, PyObject *o)
2086 {
2087 PySequenceMethods *m;
2088 PyMappingMethods *mp;
2089
2090 if (s == NULL) {
2091 null_error();
2092 return -1;
2093 }
2094
2095 m = s->ob_type->tp_as_sequence;
2096 if (m && m->sq_ass_slice) {
2097 if (i1 < 0 || i2 < 0) {
2098 if (m->sq_length) {
2099 Py_ssize_t l = (*m->sq_length)(s);
2100 if (l < 0)
2101 return -1;
2102 if (i1 < 0)
2103 i1 += l;
2104 if (i2 < 0)
2105 i2 += l;
2106 }
2107 }
2108 return m->sq_ass_slice(s, i1, i2, o);
2109 } else if ((mp = s->ob_type->tp_as_mapping) && mp->mp_ass_subscript) {
2110 int res;
2111 PyObject *slice = _PySlice_FromIndices(i1, i2);
2112 if (!slice)
2113 return -1;
2114 res = mp->mp_ass_subscript(s, slice, o);
2115 Py_DECREF(slice);
2116 return res;
2117 }
2118
2119 type_error("'%.200s' object doesn't support slice assignment", s);
2120 return -1;
2121 }
2122
2123 int
2124 PySequence_DelSlice(PyObject *s, Py_ssize_t i1, Py_ssize_t i2)
2125 {
2126 PySequenceMethods *m;
2127
2128 if (s == NULL) {
2129 null_error();
2130 return -1;
2131 }
2132
2133 m = s->ob_type->tp_as_sequence;
2134 if (m && m->sq_ass_slice) {
2135 if (i1 < 0 || i2 < 0) {
2136 if (m->sq_length) {
2137 Py_ssize_t l = (*m->sq_length)(s);
2138 if (l < 0)
2139 return -1;
2140 if (i1 < 0)
2141 i1 += l;
2142 if (i2 < 0)
2143 i2 += l;
2144 }
2145 }
2146 return m->sq_ass_slice(s, i1, i2, (PyObject *)NULL);
2147 }
2148 type_error("'%.200s' object doesn't support slice deletion", s);
2149 return -1;
2150 }
2151
2152 PyObject *
2153 PySequence_Tuple(PyObject *v)
2154 {
2155 PyObject *it; /* iter(v) */
2156 Py_ssize_t n; /* guess for result tuple size */
2157 PyObject *result = NULL;
2158 Py_ssize_t j;
2159
2160 if (v == NULL)
2161 return null_error();
2162
2163 /* Special-case the common tuple and list cases, for efficiency. */
2164 if (PyTuple_CheckExact(v)) {
2165 /* Note that we can't know whether it's safe to return
2166 a tuple *subclass* instance as-is, hence the restriction
2167 to exact tuples here. In contrast, lists always make
2168 a copy, so there's no need for exactness below. */
2169 Py_INCREF(v);
2170 return v;
2171 }
2172 if (PyList_Check(v))
2173 return PyList_AsTuple(v);
2174
2175 /* Get iterator. */
2176 it = PyObject_GetIter(v);
2177 if (it == NULL)
2178 return NULL;
2179
2180 /* Guess result size and allocate space. */
2181 n = _PyObject_LengthHint(v, 10);
2182 if (n == -1)
2183 goto Fail;
2184 result = PyTuple_New(n);
2185 if (result == NULL)
2186 goto Fail;
2187
2188 /* Fill the tuple. */
2189 for (j = 0; ; ++j) {
2190 PyObject *item = PyIter_Next(it);
2191 if (item == NULL) {
2192 if (PyErr_Occurred())
2193 goto Fail;
2194 break;
2195 }
2196 if (j >= n) {
2197 Py_ssize_t oldn = n;
2198 /* The over-allocation strategy can grow a bit faster
2199 than for lists because unlike lists the
2200 over-allocation isn't permanent -- we reclaim
2201 the excess before the end of this routine.
2202 So, grow by ten and then add 25%.
2203 */
2204 n += 10;
2205 n += n >> 2;
2206 if (n < oldn) {
2207 /* Check for overflow */
2208 PyErr_NoMemory();
2209 Py_DECREF(item);
2210 goto Fail;
2211 }
2212 if (_PyTuple_Resize(&result, n) != 0) {
2213 Py_DECREF(item);
2214 goto Fail;
2215 }
2216 }
2217 PyTuple_SET_ITEM(result, j, item);
2218 }
2219
2220 /* Cut tuple back if guess was too large. */
2221 if (j < n &&
2222 _PyTuple_Resize(&result, j) != 0)
2223 goto Fail;
2224
2225 Py_DECREF(it);
2226 return result;
2227
2228 Fail:
2229 Py_XDECREF(result);
2230 Py_DECREF(it);
2231 return NULL;
2232 }
2233
2234 PyObject *
2235 PySequence_List(PyObject *v)
2236 {
2237 PyObject *result; /* result list */
2238 PyObject *rv; /* return value from PyList_Extend */
2239
2240 if (v == NULL)
2241 return null_error();
2242
2243 result = PyList_New(0);
2244 if (result == NULL)
2245 return NULL;
2246
2247 rv = _PyList_Extend((PyListObject *)result, v);
2248 if (rv == NULL) {
2249 Py_DECREF(result);
2250 return NULL;
2251 }
2252 Py_DECREF(rv);
2253 return result;
2254 }
2255
2256 PyObject *
2257 PySequence_Fast(PyObject *v, const char *m)
2258 {
2259 PyObject *it;
2260
2261 if (v == NULL)
2262 return null_error();
2263
2264 if (PyList_CheckExact(v) || PyTuple_CheckExact(v)) {
2265 Py_INCREF(v);
2266 return v;
2267 }
2268
2269 it = PyObject_GetIter(v);
2270 if (it == NULL) {
2271 if (PyErr_ExceptionMatches(PyExc_TypeError))
2272 PyErr_SetString(PyExc_TypeError, m);
2273 return NULL;
2274 }
2275
2276 v = PySequence_List(it);
2277 Py_DECREF(it);
2278
2279 return v;
2280 }
2281
2282 /* Iterate over seq. Result depends on the operation:
2283 PY_ITERSEARCH_COUNT: -1 if error, else # of times obj appears in seq.
2284 PY_ITERSEARCH_INDEX: 0-based index of first occurrence of obj in seq;
2285 set ValueError and return -1 if none found; also return -1 on error.
2286 Py_ITERSEARCH_CONTAINS: return 1 if obj in seq, else 0; -1 on error.
2287 */
2288 Py_ssize_t
2289 _PySequence_IterSearch(PyObject *seq, PyObject *obj, int operation)
2290 {
2291 Py_ssize_t n;
2292 int wrapped; /* for PY_ITERSEARCH_INDEX, true iff n wrapped around */
2293 PyObject *it; /* iter(seq) */
2294
2295 if (seq == NULL || obj == NULL) {
2296 null_error();
2297 return -1;
2298 }
2299
2300 it = PyObject_GetIter(seq);
2301 if (it == NULL) {
2302 type_error("argument of type '%.200s' is not iterable", seq);
2303 return -1;
2304 }
2305
2306 n = wrapped = 0;
2307 for (;;) {
2308 int cmp;
2309 PyObject *item = PyIter_Next(it);
2310 if (item == NULL) {
2311 if (PyErr_Occurred())
2312 goto Fail;
2313 break;
2314 }
2315
2316 cmp = PyObject_RichCompareBool(obj, item, Py_EQ);
2317 Py_DECREF(item);
2318 if (cmp < 0)
2319 goto Fail;
2320 if (cmp > 0) {
2321 switch (operation) {
2322 case PY_ITERSEARCH_COUNT:
2323 if (n == PY_SSIZE_T_MAX) {
2324 PyErr_SetString(PyExc_OverflowError,
2325 "count exceeds C integer size");
2326 goto Fail;
2327 }
2328 ++n;
2329 break;
2330
2331 case PY_ITERSEARCH_INDEX:
2332 if (wrapped) {
2333 PyErr_SetString(PyExc_OverflowError,
2334 "index exceeds C integer size");
2335 goto Fail;
2336 }
2337 goto Done;
2338
2339 case PY_ITERSEARCH_CONTAINS:
2340 n = 1;
2341 goto Done;
2342
2343 default:
2344 assert(!"unknown operation");
2345 }
2346 }
2347
2348 if (operation == PY_ITERSEARCH_INDEX) {
2349 if (n == PY_SSIZE_T_MAX)
2350 wrapped = 1;
2351 ++n;
2352 }
2353 }
2354
2355 if (operation != PY_ITERSEARCH_INDEX)
2356 goto Done;
2357
2358 PyErr_SetString(PyExc_ValueError,
2359 "sequence.index(x): x not in sequence");
2360 /* fall into failure code */
2361 Fail:
2362 n = -1;
2363 /* fall through */
2364 Done:
2365 Py_DECREF(it);
2366 return n;
2367
2368 }
2369
2370 /* Return # of times o appears in s. */
2371 Py_ssize_t
2372 PySequence_Count(PyObject *s, PyObject *o)
2373 {
2374 return _PySequence_IterSearch(s, o, PY_ITERSEARCH_COUNT);
2375 }
2376
2377 /* Return -1 if error; 1 if ob in seq; 0 if ob not in seq.
2378 * Use sq_contains if possible, else defer to _PySequence_IterSearch().
2379 */
2380 int
2381 PySequence_Contains(PyObject *seq, PyObject *ob)
2382 {
2383 Py_ssize_t result;
2384 if (PyType_HasFeature(seq->ob_type, Py_TPFLAGS_HAVE_SEQUENCE_IN)) {
2385 PySequenceMethods *sqm = seq->ob_type->tp_as_sequence;
2386 if (sqm != NULL && sqm->sq_contains != NULL)
2387 return (*sqm->sq_contains)(seq, ob);
2388 }
2389 result = _PySequence_IterSearch(seq, ob, PY_ITERSEARCH_CONTAINS);
2390 return Py_SAFE_DOWNCAST(result, Py_ssize_t, int);
2391 }
2392
2393 /* Backwards compatibility */
2394 #undef PySequence_In
2395 int
2396 PySequence_In(PyObject *w, PyObject *v)
2397 {
2398 return PySequence_Contains(w, v);
2399 }
2400
2401 Py_ssize_t
2402 PySequence_Index(PyObject *s, PyObject *o)
2403 {
2404 return _PySequence_IterSearch(s, o, PY_ITERSEARCH_INDEX);
2405 }
2406
2407 /* Operations on mappings */
2408
2409 int
2410 PyMapping_Check(PyObject *o)
2411 {
2412 if (o && PyInstance_Check(o))
2413 return PyObject_HasAttrString(o, "__getitem__");
2414
2415 return o && o->ob_type->tp_as_mapping &&
2416 o->ob_type->tp_as_mapping->mp_subscript &&
2417 !(o->ob_type->tp_as_sequence &&
2418 o->ob_type->tp_as_sequence->sq_slice);
2419 }
2420
2421 Py_ssize_t
2422 PyMapping_Size(PyObject *o)
2423 {
2424 PyMappingMethods *m;
2425
2426 if (o == NULL) {
2427 null_error();
2428 return -1;
2429 }
2430
2431 m = o->ob_type->tp_as_mapping;
2432 if (m && m->mp_length)
2433 return m->mp_length(o);
2434
2435 type_error("object of type '%.200s' has no len()", o);
2436 return -1;
2437 }
2438
2439 #undef PyMapping_Length
2440 Py_ssize_t
2441 PyMapping_Length(PyObject *o)
2442 {
2443 return PyMapping_Size(o);
2444 }
2445 #define PyMapping_Length PyMapping_Size
2446
2447 PyObject *
2448 PyMapping_GetItemString(PyObject *o, char *key)
2449 {
2450 PyObject *okey, *r;
2451
2452 if (key == NULL)
2453 return null_error();
2454
2455 okey = PyString_FromString(key);
2456 if (okey == NULL)
2457 return NULL;
2458 r = PyObject_GetItem(o, okey);
2459 Py_DECREF(okey);
2460 return r;
2461 }
2462
2463 int
2464 PyMapping_SetItemString(PyObject *o, char *key, PyObject *value)
2465 {
2466 PyObject *okey;
2467 int r;
2468
2469 if (key == NULL) {
2470 null_error();
2471 return -1;
2472 }
2473
2474 okey = PyString_FromString(key);
2475 if (okey == NULL)
2476 return -1;
2477 r = PyObject_SetItem(o, okey, value);
2478 Py_DECREF(okey);
2479 return r;
2480 }
2481
2482 int
2483 PyMapping_HasKeyString(PyObject *o, char *key)
2484 {
2485 PyObject *v;
2486
2487 v = PyMapping_GetItemString(o, key);
2488 if (v) {
2489 Py_DECREF(v);
2490 return 1;
2491 }
2492 PyErr_Clear();
2493 return 0;
2494 }
2495
2496 int
2497 PyMapping_HasKey(PyObject *o, PyObject *key)
2498 {
2499 PyObject *v;
2500
2501 v = PyObject_GetItem(o, key);
2502 if (v) {
2503 Py_DECREF(v);
2504 return 1;
2505 }
2506 PyErr_Clear();
2507 return 0;
2508 }
2509
2510 /* Operations on callable objects */
2511
2512 /* XXX PyCallable_Check() is in object.c */
2513
2514 PyObject *
2515 PyObject_CallObject(PyObject *o, PyObject *a)
2516 {
2517 return PyEval_CallObjectWithKeywords(o, a, NULL);
2518 }
2519
2520 PyObject *
2521 PyObject_Call(PyObject *func, PyObject *arg, PyObject *kw)
2522 {
2523 ternaryfunc call;
2524
2525 if ((call = func->ob_type->tp_call) != NULL) {
2526 PyObject *result;
2527 if (Py_EnterRecursiveCall(" while calling a Python object"))
2528 return NULL;
2529 result = (*call)(func, arg, kw);
2530 Py_LeaveRecursiveCall();
2531 if (result == NULL && !PyErr_Occurred())
2532 PyErr_SetString(
2533 PyExc_SystemError,
2534 "NULL result without error in PyObject_Call");
2535 return result;
2536 }
2537 PyErr_Format(PyExc_TypeError, "'%.200s' object is not callable",
2538 func->ob_type->tp_name);
2539 return NULL;
2540 }
2541
2542 static PyObject*
2543 call_function_tail(PyObject *callable, PyObject *args)
2544 {
2545 PyObject *retval;
2546
2547 if (args == NULL)
2548 return NULL;
2549
2550 if (!PyTuple_Check(args)) {
2551 PyObject *a;
2552
2553 a = PyTuple_New(1);
2554 if (a == NULL) {
2555 Py_DECREF(args);
2556 return NULL;
2557 }
2558 PyTuple_SET_ITEM(a, 0, args);
2559 args = a;
2560 }
2561 retval = PyObject_Call(callable, args, NULL);
2562
2563 Py_DECREF(args);
2564
2565 return retval;
2566 }
2567
2568 PyObject *
2569 PyObject_CallFunction(PyObject *callable, char *format, ...)
2570 {
2571 va_list va;
2572 PyObject *args;
2573
2574 if (callable == NULL)
2575 return null_error();
2576
2577 if (format && *format) {
2578 va_start(va, format);
2579 args = Py_VaBuildValue(format, va);
2580 va_end(va);
2581 }
2582 else
2583 args = PyTuple_New(0);
2584
2585 return call_function_tail(callable, args);
2586 }
2587
2588 PyObject *
2589 _PyObject_CallFunction_SizeT(PyObject *callable, char *format, ...)
2590 {
2591 va_list va;
2592 PyObject *args;
2593
2594 if (callable == NULL)
2595 return null_error();
2596
2597 if (format && *format) {
2598 va_start(va, format);
2599 args = _Py_VaBuildValue_SizeT(format, va);
2600 va_end(va);
2601 }
2602 else
2603 args = PyTuple_New(0);
2604
2605 return call_function_tail(callable, args);
2606 }
2607
2608 PyObject *
2609 PyObject_CallMethod(PyObject *o, char *name, char *format, ...)
2610 {
2611 va_list va;
2612 PyObject *args;
2613 PyObject *func = NULL;
2614 PyObject *retval = NULL;
2615
2616 if (o == NULL || name == NULL)
2617 return null_error();
2618
2619 func = PyObject_GetAttrString(o, name);
2620 if (func == NULL)
2621 return NULL;
2622
2623 if (!PyCallable_Check(func)) {
2624 type_error("attribute of type '%.200s' is not callable", func);
2625 goto exit;
2626 }
2627
2628 if (format && *format) {
2629 va_start(va, format);
2630 args = Py_VaBuildValue(format, va);
2631 va_end(va);
2632 }
2633 else
2634 args = PyTuple_New(0);
2635
2636 retval = call_function_tail(func, args);
2637
2638 exit:
2639 /* args gets consumed in call_function_tail */
2640 Py_XDECREF(func);
2641
2642 return retval;
2643 }
2644
2645 PyObject *
2646 _PyObject_CallMethod_SizeT(PyObject *o, char *name, char *format, ...)
2647 {
2648 va_list va;
2649 PyObject *args;
2650 PyObject *func = NULL;
2651 PyObject *retval = NULL;
2652
2653 if (o == NULL || name == NULL)
2654 return null_error();
2655
2656 func = PyObject_GetAttrString(o, name);
2657 if (func == NULL)
2658 return NULL;
2659
2660 if (!PyCallable_Check(func)) {
2661 type_error("attribute of type '%.200s' is not callable", func);
2662 goto exit;
2663 }
2664
2665 if (format && *format) {
2666 va_start(va, format);
2667 args = _Py_VaBuildValue_SizeT(format, va);
2668 va_end(va);
2669 }
2670 else
2671 args = PyTuple_New(0);
2672
2673 retval = call_function_tail(func, args);
2674
2675 exit:
2676 /* args gets consumed in call_function_tail */
2677 Py_XDECREF(func);
2678
2679 return retval;
2680 }
2681
2682
2683 static PyObject *
2684 objargs_mktuple(va_list va)
2685 {
2686 int i, n = 0;
2687 va_list countva;
2688 PyObject *result, *tmp;
2689
2690 #ifdef VA_LIST_IS_ARRAY
2691 memcpy(countva, va, sizeof(va_list));
2692 #else
2693 #ifdef __va_copy
2694 __va_copy(countva, va);
2695 #else
2696 countva = va;
2697 #endif
2698 #endif
2699
2700 while (((PyObject *)va_arg(countva, PyObject *)) != NULL)
2701 ++n;
2702 result = PyTuple_New(n);
2703 if (result != NULL && n > 0) {
2704 for (i = 0; i < n; ++i) {
2705 tmp = (PyObject *)va_arg(va, PyObject *);
2706 PyTuple_SET_ITEM(result, i, tmp);
2707 Py_INCREF(tmp);
2708 }
2709 }
2710 return result;
2711 }
2712
2713 PyObject *
2714 PyObject_CallMethodObjArgs(PyObject *callable, PyObject *name, ...)
2715 {
2716 PyObject *args, *tmp;
2717 va_list vargs;
2718
2719 if (callable == NULL || name == NULL)
2720 return null_error();
2721
2722 callable = PyObject_GetAttr(callable, name);
2723 if (callable == NULL)
2724 return NULL;
2725
2726 /* count the args */
2727 va_start(vargs, name);
2728 args = objargs_mktuple(vargs);
2729 va_end(vargs);
2730 if (args == NULL) {
2731 Py_DECREF(callable);
2732 return NULL;
2733 }
2734 tmp = PyObject_Call(callable, args, NULL);
2735 Py_DECREF(args);
2736 Py_DECREF(callable);
2737
2738 return tmp;
2739 }
2740
2741 PyObject *
2742 PyObject_CallFunctionObjArgs(PyObject *callable, ...)
2743 {
2744 PyObject *args, *tmp;
2745 va_list vargs;
2746
2747 if (callable == NULL)
2748 return null_error();
2749
2750 /* count the args */
2751 va_start(vargs, callable);
2752 args = objargs_mktuple(vargs);
2753 va_end(vargs);
2754 if (args == NULL)
2755 return NULL;
2756 tmp = PyObject_Call(callable, args, NULL);
2757 Py_DECREF(args);
2758
2759 return tmp;
2760 }
2761
2762
2763 /* isinstance(), issubclass() */
2764
2765 /* abstract_get_bases() has logically 4 return states, with a sort of 0th
2766 * state that will almost never happen.
2767 *
2768 * 0. creating the __bases__ static string could get a MemoryError
2769 * 1. getattr(cls, '__bases__') could raise an AttributeError
2770 * 2. getattr(cls, '__bases__') could raise some other exception
2771 * 3. getattr(cls, '__bases__') could return a tuple
2772 * 4. getattr(cls, '__bases__') could return something other than a tuple
2773 *
2774 * Only state #3 is a non-error state and only it returns a non-NULL object
2775 * (it returns the retrieved tuple).
2776 *
2777 * Any raised AttributeErrors are masked by clearing the exception and
2778 * returning NULL. If an object other than a tuple comes out of __bases__,
2779 * then again, the return value is NULL. So yes, these two situations
2780 * produce exactly the same results: NULL is returned and no error is set.
2781 *
2782 * If some exception other than AttributeError is raised, then NULL is also
2783 * returned, but the exception is not cleared. That's because we want the
2784 * exception to be propagated along.
2785 *
2786 * Callers are expected to test for PyErr_Occurred() when the return value
2787 * is NULL to decide whether a valid exception should be propagated or not.
2788 * When there's no exception to propagate, it's customary for the caller to
2789 * set a TypeError.
2790 */
2791 static PyObject *
2792 abstract_get_bases(PyObject *cls)
2793 {
2794 static PyObject *__bases__ = NULL;
2795 PyObject *bases;
2796
2797 if (__bases__ == NULL) {
2798 __bases__ = PyString_InternFromString("__bases__");
2799 if (__bases__ == NULL)
2800 return NULL;
2801 }
2802 bases = PyObject_GetAttr(cls, __bases__);
2803 if (bases == NULL) {
2804 if (PyErr_ExceptionMatches(PyExc_AttributeError))
2805 PyErr_Clear();
2806 return NULL;
2807 }
2808 if (!PyTuple_Check(bases)) {
2809 Py_DECREF(bases);
2810 return NULL;
2811 }
2812 return bases;
2813 }
2814
2815
2816 static int
2817 abstract_issubclass(PyObject *derived, PyObject *cls)
2818 {
2819 PyObject *bases = NULL;
2820 Py_ssize_t i, n;
2821 int r = 0;
2822
2823 while (1) {
2824 if (derived == cls)
2825 return 1;
2826 bases = abstract_get_bases(derived);
2827 if (bases == NULL) {
2828 if (PyErr_Occurred())
2829 return -1;
2830 return 0;
2831 }
2832 n = PyTuple_GET_SIZE(bases);
2833 if (n == 0) {
2834 Py_DECREF(bases);
2835 return 0;
2836 }
2837 /* Avoid recursivity in the single inheritance case */
2838 if (n == 1) {
2839 derived = PyTuple_GET_ITEM(bases, 0);
2840 Py_DECREF(bases);
2841 continue;
2842 }
2843 for (i = 0; i < n; i++) {
2844 r = abstract_issubclass(PyTuple_GET_ITEM(bases, i), cls);
2845 if (r != 0)
2846 break;
2847 }
2848 Py_DECREF(bases);
2849 return r;
2850 }
2851 }
2852
2853 static int
2854 check_class(PyObject *cls, const char *error)
2855 {
2856 PyObject *bases = abstract_get_bases(cls);
2857 if (bases == NULL) {
2858 /* Do not mask errors. */
2859 if (!PyErr_Occurred())
2860 PyErr_SetString(PyExc_TypeError, error);
2861 return 0;
2862 }
2863 Py_DECREF(bases);
2864 return -1;
2865 }
2866
2867 static int
2868 recursive_isinstance(PyObject *inst, PyObject *cls)
2869 {
2870 PyObject *icls;
2871 static PyObject *__class__ = NULL;
2872 int retval = 0;
2873
2874 if (__class__ == NULL) {
2875 __class__ = PyString_InternFromString("__class__");
2876 if (__class__ == NULL)
2877 return -1;
2878 }
2879
2880 if (PyClass_Check(cls) && PyInstance_Check(inst)) {
2881 PyObject *inclass =
2882 (PyObject*)((PyInstanceObject*)inst)->in_class;
2883 retval = PyClass_IsSubclass(inclass, cls);
2884 }
2885 else if (PyType_Check(cls)) {
2886 retval = PyObject_TypeCheck(inst, (PyTypeObject *)cls);
2887 if (retval == 0) {
2888 PyObject *c = PyObject_GetAttr(inst, __class__);
2889 if (c == NULL) {
2890 PyErr_Clear();
2891 }
2892 else {
2893 if (c != (PyObject *)(inst->ob_type) &&
2894 PyType_Check(c))
2895 retval = PyType_IsSubtype(
2896 (PyTypeObject *)c,
2897 (PyTypeObject *)cls);
2898 Py_DECREF(c);
2899 }
2900 }
2901 }
2902 else {
2903 if (!check_class(cls,
2904 "isinstance() arg 2 must be a class, type,"
2905 " or tuple of classes and types"))
2906 return -1;
2907 icls = PyObject_GetAttr(inst, __class__);
2908 if (icls == NULL) {
2909 PyErr_Clear();
2910 retval = 0;
2911 }
2912 else {
2913 retval = abstract_issubclass(icls, cls);
2914 Py_DECREF(icls);
2915 }
2916 }
2917
2918 return retval;
2919 }
2920
2921 int
2922 PyObject_IsInstance(PyObject *inst, PyObject *cls)
2923 {
2924 static PyObject *name = NULL;
2925
2926 /* Quick test for an exact match */
2927 if (Py_TYPE(inst) == (PyTypeObject *)cls)
2928 return 1;
2929
2930 if (PyTuple_Check(cls)) {
2931 Py_ssize_t i;
2932 Py_ssize_t n;
2933 int r = 0;
2934
2935 if (Py_EnterRecursiveCall(" in __instancecheck__"))
2936 return -1;
2937 n = PyTuple_GET_SIZE(cls);
2938 for (i = 0; i < n; ++i) {
2939 PyObject *item = PyTuple_GET_ITEM(cls, i);
2940 r = PyObject_IsInstance(inst, item);
2941 if (r != 0)
2942 /* either found it, or got an error */
2943 break;
2944 }
2945 Py_LeaveRecursiveCall();
2946 return r;
2947 }
2948
2949 if (!(PyClass_Check(cls) || PyInstance_Check(cls))) {
2950 PyObject *checker;
2951 checker = _PyObject_LookupSpecial(cls, "__instancecheck__", &name);
2952 if (checker != NULL) {
2953 PyObject *res;
2954 int ok = -1;
2955 if (Py_EnterRecursiveCall(" in __instancecheck__")) {
2956 Py_DECREF(checker);
2957 return ok;
2958 }
2959 res = PyObject_CallFunctionObjArgs(checker, inst, NULL);
2960 Py_LeaveRecursiveCall();
2961 Py_DECREF(checker);
2962 if (res != NULL) {
2963 ok = PyObject_IsTrue(res);
2964 Py_DECREF(res);
2965 }
2966 return ok;
2967 }
2968 else if (PyErr_Occurred())
2969 return -1;
2970 }
2971 return recursive_isinstance(inst, cls);
2972 }
2973
2974 static int
2975 recursive_issubclass(PyObject *derived, PyObject *cls)
2976 {
2977 int retval;
2978
2979 if (PyType_Check(cls) && PyType_Check(derived)) {
2980 /* Fast path (non-recursive) */
2981 return PyType_IsSubtype(
2982 (PyTypeObject *)derived, (PyTypeObject *)cls);
2983 }
2984 if (!PyClass_Check(derived) || !PyClass_Check(cls)) {
2985 if (!check_class(derived,
2986 "issubclass() arg 1 must be a class"))
2987 return -1;
2988
2989 if (!check_class(cls,
2990 "issubclass() arg 2 must be a class"
2991 " or tuple of classes"))
2992 return -1;
2993 retval = abstract_issubclass(derived, cls);
2994 }
2995 else {
2996 /* shortcut */
2997 if (!(retval = (derived == cls)))
2998 retval = PyClass_IsSubclass(derived, cls);
2999 }
3000
3001 return retval;
3002 }
3003
3004 int
3005 PyObject_IsSubclass(PyObject *derived, PyObject *cls)
3006 {
3007 static PyObject *name = NULL;
3008
3009 if (PyTuple_Check(cls)) {
3010 Py_ssize_t i;
3011 Py_ssize_t n;
3012 int r = 0;
3013
3014 if (Py_EnterRecursiveCall(" in __subclasscheck__"))
3015 return -1;
3016 n = PyTuple_GET_SIZE(cls);
3017 for (i = 0; i < n; ++i) {
3018 PyObject *item = PyTuple_GET_ITEM(cls, i);
3019 r = PyObject_IsSubclass(derived, item);
3020 if (r != 0)
3021 /* either found it, or got an error */
3022 break;
3023 }
3024 Py_LeaveRecursiveCall();
3025 return r;
3026 }
3027 if (!(PyClass_Check(cls) || PyInstance_Check(cls))) {
3028 PyObject *checker;
3029 checker = _PyObject_LookupSpecial(cls, "__subclasscheck__", &name);
3030 if (checker != NULL) {
3031 PyObject *res;
3032 int ok = -1;
3033 if (Py_EnterRecursiveCall(" in __subclasscheck__")) {
3034 Py_DECREF(checker);
3035 return ok;
3036 }
3037 res = PyObject_CallFunctionObjArgs(checker, derived, NULL);
3038 Py_LeaveRecursiveCall();
3039 Py_DECREF(checker);
3040 if (res != NULL) {
3041 ok = PyObject_IsTrue(res);
3042 Py_DECREF(res);
3043 }
3044 return ok;
3045 }
3046 else if (PyErr_Occurred()) {
3047 return -1;
3048 }
3049 }
3050 return recursive_issubclass(derived, cls);
3051 }
3052
3053 int
3054 _PyObject_RealIsInstance(PyObject *inst, PyObject *cls)
3055 {
3056 return recursive_isinstance(inst, cls);
3057 }
3058
3059 int
3060 _PyObject_RealIsSubclass(PyObject *derived, PyObject *cls)
3061 {
3062 return recursive_issubclass(derived, cls);
3063 }
3064
3065
3066 PyObject *
3067 PyObject_GetIter(PyObject *o)
3068 {
3069 PyTypeObject *t = o->ob_type;
3070 getiterfunc f = NULL;
3071 if (PyType_HasFeature(t, Py_TPFLAGS_HAVE_ITER))
3072 f = t->tp_iter;
3073 if (f == NULL) {
3074 if (PySequence_Check(o))
3075 return PySeqIter_New(o);
3076 return type_error("'%.200s' object is not iterable", o);
3077 }
3078 else {
3079 PyObject *res = (*f)(o);
3080 if (res != NULL && !PyIter_Check(res)) {
3081 PyErr_Format(PyExc_TypeError,
3082 "iter() returned non-iterator "
3083 "of type '%.100s'",
3084 res->ob_type->tp_name);
3085 Py_DECREF(res);
3086 res = NULL;
3087 }
3088 return res;
3089 }
3090 }
3091
3092 /* Return next item.
3093 * If an error occurs, return NULL. PyErr_Occurred() will be true.
3094 * If the iteration terminates normally, return NULL and clear the
3095 * PyExc_StopIteration exception (if it was set). PyErr_Occurred()
3096 * will be false.
3097 * Else return the next object. PyErr_Occurred() will be false.
3098 */
3099 PyObject *
3100 PyIter_Next(PyObject *iter)
3101 {
3102 PyObject *result;
3103 result = (*iter->ob_type->tp_iternext)(iter);
3104 if (result == NULL &&
3105 PyErr_Occurred() &&
3106 PyErr_ExceptionMatches(PyExc_StopIteration))
3107 PyErr_Clear();
3108 return result;
3109 }
3110