aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/tools/python3/Objects/methodobject.c
blob: 44735045163f6b93d5df157ea24e9b6dbd26d620 (plain) (blame)
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
/* Method object implementation */

#include "Python.h"
#include "pycore_ceval.h"         // _Py_EnterRecursiveCallTstate()
#include "pycore_object.h"
#include "pycore_pyerrors.h"
#include "pycore_pystate.h"       // _PyThreadState_GET()
#include "structmember.h"         // PyMemberDef

/* undefine macro trampoline to PyCFunction_NewEx */
#undef PyCFunction_New
/* undefine macro trampoline to PyCMethod_New */
#undef PyCFunction_NewEx

/* Forward declarations */
static PyObject * cfunction_vectorcall_FASTCALL(
    PyObject *func, PyObject *const *args, size_t nargsf, PyObject *kwnames);
static PyObject * cfunction_vectorcall_FASTCALL_KEYWORDS(
    PyObject *func, PyObject *const *args, size_t nargsf, PyObject *kwnames);
static PyObject * cfunction_vectorcall_FASTCALL_KEYWORDS_METHOD(
    PyObject *func, PyObject *const *args, size_t nargsf, PyObject *kwnames);
static PyObject * cfunction_vectorcall_NOARGS(
    PyObject *func, PyObject *const *args, size_t nargsf, PyObject *kwnames);
static PyObject * cfunction_vectorcall_O(
    PyObject *func, PyObject *const *args, size_t nargsf, PyObject *kwnames);
static PyObject * cfunction_call(
    PyObject *func, PyObject *args, PyObject *kwargs);


PyObject *
PyCFunction_New(PyMethodDef *ml, PyObject *self)
{
    return PyCFunction_NewEx(ml, self, NULL);
}

PyObject *
PyCFunction_NewEx(PyMethodDef *ml, PyObject *self, PyObject *module)
{
    return PyCMethod_New(ml, self, module, NULL);
}

PyObject *
PyCMethod_New(PyMethodDef *ml, PyObject *self, PyObject *module, PyTypeObject *cls)
{
    /* Figure out correct vectorcall function to use */
    vectorcallfunc vectorcall;
    switch (ml->ml_flags & (METH_VARARGS | METH_FASTCALL | METH_NOARGS |
                            METH_O | METH_KEYWORDS | METH_METHOD))
    {
        case METH_VARARGS:
        case METH_VARARGS | METH_KEYWORDS:
            /* For METH_VARARGS functions, it's more efficient to use tp_call
             * instead of vectorcall. */
            vectorcall = NULL;
            break;
        case METH_FASTCALL:
            vectorcall = cfunction_vectorcall_FASTCALL;
            break;
        case METH_FASTCALL | METH_KEYWORDS:
            vectorcall = cfunction_vectorcall_FASTCALL_KEYWORDS;
            break;
        case METH_NOARGS:
            vectorcall = cfunction_vectorcall_NOARGS;
            break;
        case METH_O:
            vectorcall = cfunction_vectorcall_O;
            break;
        case METH_METHOD | METH_FASTCALL | METH_KEYWORDS:
            vectorcall = cfunction_vectorcall_FASTCALL_KEYWORDS_METHOD;
            break;
        default:
            PyErr_Format(PyExc_SystemError,
                         "%s() method: bad call flags", ml->ml_name);
            return NULL;
    }

    PyCFunctionObject *op = NULL;

    if (ml->ml_flags & METH_METHOD) {
        if (!cls) {
            PyErr_SetString(PyExc_SystemError,
                            "attempting to create PyCMethod with a METH_METHOD "
                            "flag but no class");
            return NULL;
        }
        PyCMethodObject *om = PyObject_GC_New(PyCMethodObject, &PyCMethod_Type);
        if (om == NULL) {
            return NULL;
        }
        om->mm_class = (PyTypeObject*)Py_NewRef(cls);
        op = (PyCFunctionObject *)om;
    } else {
        if (cls) {
            PyErr_SetString(PyExc_SystemError,
                            "attempting to create PyCFunction with class "
                            "but no METH_METHOD flag");
            return NULL;
        }
        op = PyObject_GC_New(PyCFunctionObject, &PyCFunction_Type);
        if (op == NULL) {
            return NULL;
        }
    }

    op->m_weakreflist = NULL;
    op->m_ml = ml;
    op->m_self = Py_XNewRef(self);
    op->m_module = Py_XNewRef(module);
    op->vectorcall = vectorcall;
    _PyObject_GC_TRACK(op);
    return (PyObject *)op;
}

PyCFunction
PyCFunction_GetFunction(PyObject *op)
{
    if (!PyCFunction_Check(op)) {
        PyErr_BadInternalCall();
        return NULL;
    }
    return PyCFunction_GET_FUNCTION(op);
}

PyObject *
PyCFunction_GetSelf(PyObject *op)
{
    if (!PyCFunction_Check(op)) {
        PyErr_BadInternalCall();
        return NULL;
    }
    return PyCFunction_GET_SELF(op);
}

int
PyCFunction_GetFlags(PyObject *op)
{
    if (!PyCFunction_Check(op)) {
        PyErr_BadInternalCall();
        return -1;
    }
    return PyCFunction_GET_FLAGS(op);
}

PyTypeObject *
PyCMethod_GetClass(PyObject *op)
{
    if (!PyCFunction_Check(op)) {
        PyErr_BadInternalCall();
        return NULL;
    }
    return PyCFunction_GET_CLASS(op);
}

/* Methods (the standard built-in methods, that is) */

static void
meth_dealloc(PyCFunctionObject *m)
{
    // The Py_TRASHCAN mechanism requires that we be able to
    // call PyObject_GC_UnTrack twice on an object.
    PyObject_GC_UnTrack(m);
    Py_TRASHCAN_BEGIN(m, meth_dealloc);
    if (m->m_weakreflist != NULL) {
        PyObject_ClearWeakRefs((PyObject*) m);
    }
    // Dereference class before m_self: PyCFunction_GET_CLASS accesses
    // PyMethodDef m_ml, which could be kept alive by m_self
    Py_XDECREF(PyCFunction_GET_CLASS(m));
    Py_XDECREF(m->m_self);
    Py_XDECREF(m->m_module);
    PyObject_GC_Del(m);
    Py_TRASHCAN_END;
}

static PyObject *
meth_reduce(PyCFunctionObject *m, PyObject *Py_UNUSED(ignored))
{
    if (m->m_self == NULL || PyModule_Check(m->m_self))
        return PyUnicode_FromString(m->m_ml->ml_name);

    return Py_BuildValue("N(Os)", _PyEval_GetBuiltin(&_Py_ID(getattr)),
                         m->m_self, m->m_ml->ml_name);
}

static PyMethodDef meth_methods[] = {
    {"__reduce__", (PyCFunction)meth_reduce, METH_NOARGS, NULL},
    {NULL, NULL}
};

static PyObject *
meth_get__text_signature__(PyCFunctionObject *m, void *closure)
{
    return _PyType_GetTextSignatureFromInternalDoc(m->m_ml->ml_name, m->m_ml->ml_doc);
}

static PyObject *
meth_get__doc__(PyCFunctionObject *m, void *closure)
{
    return _PyType_GetDocFromInternalDoc(m->m_ml->ml_name, m->m_ml->ml_doc);
}

static PyObject *
meth_get__name__(PyCFunctionObject *m, void *closure)
{
    return PyUnicode_FromString(m->m_ml->ml_name);
}

static PyObject *
meth_get__qualname__(PyCFunctionObject *m, void *closure)
{
    /* If __self__ is a module or NULL, return m.__name__
       (e.g. len.__qualname__ == 'len')

       If __self__ is a type, return m.__self__.__qualname__ + '.' + m.__name__
       (e.g. dict.fromkeys.__qualname__ == 'dict.fromkeys')

       Otherwise return type(m.__self__).__qualname__ + '.' + m.__name__
       (e.g. [].append.__qualname__ == 'list.append') */
    PyObject *type, *type_qualname, *res;

    if (m->m_self == NULL || PyModule_Check(m->m_self))
        return PyUnicode_FromString(m->m_ml->ml_name);

    type = PyType_Check(m->m_self) ? m->m_self : (PyObject*)Py_TYPE(m->m_self);

    type_qualname = PyObject_GetAttr(type, &_Py_ID(__qualname__));
    if (type_qualname == NULL)
        return NULL;

    if (!PyUnicode_Check(type_qualname)) {
        PyErr_SetString(PyExc_TypeError, "<method>.__class__."
                        "__qualname__ is not a unicode object");
        Py_XDECREF(type_qualname);
        return NULL;
    }

    res = PyUnicode_FromFormat("%S.%s", type_qualname, m->m_ml->ml_name);
    Py_DECREF(type_qualname);
    return res;
}

static int
meth_traverse(PyCFunctionObject *m, visitproc visit, void *arg)
{
    Py_VISIT(PyCFunction_GET_CLASS(m));
    Py_VISIT(m->m_self);
    Py_VISIT(m->m_module);
    return 0;
}

static PyObject *
meth_get__self__(PyCFunctionObject *m, void *closure)
{
    PyObject *self;

    self = PyCFunction_GET_SELF(m);
    if (self == NULL)
        self = Py_None;
    return Py_NewRef(self);
}

static PyGetSetDef meth_getsets [] = {
    {"__doc__",  (getter)meth_get__doc__,  NULL, NULL},
    {"__name__", (getter)meth_get__name__, NULL, NULL},
    {"__qualname__", (getter)meth_get__qualname__, NULL, NULL},
    {"__self__", (getter)meth_get__self__, NULL, NULL},
    {"__text_signature__", (getter)meth_get__text_signature__, NULL, NULL},
    {0}
};

#define OFF(x) offsetof(PyCFunctionObject, x)

static PyMemberDef meth_members[] = {
    {"__module__",    T_OBJECT,     OFF(m_module), 0},
    {NULL}
};

static PyObject *
meth_repr(PyCFunctionObject *m)
{
    if (m->m_self == NULL || PyModule_Check(m->m_self))
        return PyUnicode_FromFormat("<built-in function %s>",
                                   m->m_ml->ml_name);
    return PyUnicode_FromFormat("<built-in method %s of %s object at %p>",
                               m->m_ml->ml_name,
                               Py_TYPE(m->m_self)->tp_name,
                               m->m_self);
}

static PyObject *
meth_richcompare(PyObject *self, PyObject *other, int op)
{
    PyCFunctionObject *a, *b;
    PyObject *res;
    int eq;

    if ((op != Py_EQ && op != Py_NE) ||
        !PyCFunction_Check(self) ||
        !PyCFunction_Check(other))
    {
        Py_RETURN_NOTIMPLEMENTED;
    }
    a = (PyCFunctionObject *)self;
    b = (PyCFunctionObject *)other;
    eq = a->m_self == b->m_self;
    if (eq)
        eq = a->m_ml->ml_meth == b->m_ml->ml_meth;
    if (op == Py_EQ)
        res = eq ? Py_True : Py_False;
    else
        res = eq ? Py_False : Py_True;
    return Py_NewRef(res);
}

static Py_hash_t
meth_hash(PyCFunctionObject *a)
{
    Py_hash_t x, y;
    x = _Py_HashPointer(a->m_self);
    y = _Py_HashPointer((void*)(a->m_ml->ml_meth));
    x ^= y;
    if (x == -1)
        x = -2;
    return x;
}


PyTypeObject PyCFunction_Type = {
    PyVarObject_HEAD_INIT(&PyType_Type, 0)
    "builtin_function_or_method",
    sizeof(PyCFunctionObject),
    0,
    (destructor)meth_dealloc,                   /* tp_dealloc */
    offsetof(PyCFunctionObject, vectorcall),    /* tp_vectorcall_offset */
    0,                                          /* tp_getattr */
    0,                                          /* tp_setattr */
    0,                                          /* tp_as_async */
    (reprfunc)meth_repr,                        /* tp_repr */
    0,                                          /* tp_as_number */
    0,                                          /* tp_as_sequence */
    0,                                          /* tp_as_mapping */
    (hashfunc)meth_hash,                        /* tp_hash */
    cfunction_call,                             /* tp_call */
    0,                                          /* tp_str */
    PyObject_GenericGetAttr,                    /* tp_getattro */
    0,                                          /* tp_setattro */
    0,                                          /* tp_as_buffer */
    Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC |
    Py_TPFLAGS_HAVE_VECTORCALL,                 /* tp_flags */
    0,                                          /* tp_doc */
    (traverseproc)meth_traverse,                /* tp_traverse */
    0,                                          /* tp_clear */
    meth_richcompare,                           /* tp_richcompare */
    offsetof(PyCFunctionObject, m_weakreflist), /* tp_weaklistoffset */
    0,                                          /* tp_iter */
    0,                                          /* tp_iternext */
    meth_methods,                               /* tp_methods */
    meth_members,                               /* tp_members */
    meth_getsets,                               /* tp_getset */
    0,                                          /* tp_base */
    0,                                          /* tp_dict */
};

PyTypeObject PyCMethod_Type = {
    PyVarObject_HEAD_INIT(&PyType_Type, 0)
    .tp_name = "builtin_method",
    .tp_basicsize = sizeof(PyCMethodObject),
    .tp_base = &PyCFunction_Type,
};

/* Vectorcall functions for each of the PyCFunction calling conventions,
 * except for METH_VARARGS (possibly combined with METH_KEYWORDS) which
 * doesn't use vectorcall.
 *
 * First, common helpers
 */

static inline int
cfunction_check_kwargs(PyThreadState *tstate, PyObject *func, PyObject *kwnames)
{
    assert(!_PyErr_Occurred(tstate));
    assert(PyCFunction_Check(func));
    if (kwnames && PyTuple_GET_SIZE(kwnames)) {
        PyObject *funcstr = _PyObject_FunctionStr(func);
        if (funcstr != NULL) {
            _PyErr_Format(tstate, PyExc_TypeError,
                         "%U takes no keyword arguments", funcstr);
            Py_DECREF(funcstr);
        }
        return -1;
    }
    return 0;
}

typedef void (*funcptr)(void);

static inline funcptr
cfunction_enter_call(PyThreadState *tstate, PyObject *func)
{
    if (_Py_EnterRecursiveCallTstate(tstate, " while calling a Python object")) {
        return NULL;
    }
    return (funcptr)PyCFunction_GET_FUNCTION(func);
}

/* Now the actual vectorcall functions */
static PyObject *
cfunction_vectorcall_FASTCALL(
    PyObject *func, PyObject *const *args, size_t nargsf, PyObject *kwnames)
{
    PyThreadState *tstate = _PyThreadState_GET();
    if (cfunction_check_kwargs(tstate, func, kwnames)) {
        return NULL;
    }
    Py_ssize_t nargs = PyVectorcall_NARGS(nargsf);
    _PyCFunctionFast meth = (_PyCFunctionFast)
                            cfunction_enter_call(tstate, func);
    if (meth == NULL) {
        return NULL;
    }
    PyObject *result = meth(PyCFunction_GET_SELF(func), args, nargs);
    _Py_LeaveRecursiveCallTstate(tstate);
    return result;
}

static PyObject *
cfunction_vectorcall_FASTCALL_KEYWORDS(
    PyObject *func, PyObject *const *args, size_t nargsf, PyObject *kwnames)
{
    PyThreadState *tstate = _PyThreadState_GET();
    Py_ssize_t nargs = PyVectorcall_NARGS(nargsf);
    _PyCFunctionFastWithKeywords meth = (_PyCFunctionFastWithKeywords)
                                        cfunction_enter_call(tstate, func);
    if (meth == NULL) {
        return NULL;
    }
    PyObject *result = meth(PyCFunction_GET_SELF(func), args, nargs, kwnames);
    _Py_LeaveRecursiveCallTstate(tstate);
    return result;
}

static PyObject *
cfunction_vectorcall_FASTCALL_KEYWORDS_METHOD(
    PyObject *func, PyObject *const *args, size_t nargsf, PyObject *kwnames)
{
    PyThreadState *tstate = _PyThreadState_GET();
    PyTypeObject *cls = PyCFunction_GET_CLASS(func);
    Py_ssize_t nargs = PyVectorcall_NARGS(nargsf);
    PyCMethod meth = (PyCMethod)cfunction_enter_call(tstate, func);
    if (meth == NULL) {
        return NULL;
    }
    PyObject *result = meth(PyCFunction_GET_SELF(func), cls, args, nargs, kwnames);
    _Py_LeaveRecursiveCallTstate(tstate);
    return result;
}

static PyObject *
cfunction_vectorcall_NOARGS(
    PyObject *func, PyObject *const *args, size_t nargsf, PyObject *kwnames)
{
    PyThreadState *tstate = _PyThreadState_GET();
    if (cfunction_check_kwargs(tstate, func, kwnames)) {
        return NULL;
    }
    Py_ssize_t nargs = PyVectorcall_NARGS(nargsf);
    if (nargs != 0) {
        PyObject *funcstr = _PyObject_FunctionStr(func);
        if (funcstr != NULL) {
            _PyErr_Format(tstate, PyExc_TypeError,
                "%U takes no arguments (%zd given)", funcstr, nargs);
            Py_DECREF(funcstr);
        }
        return NULL;
    }
    PyCFunction meth = (PyCFunction)cfunction_enter_call(tstate, func);
    if (meth == NULL) {
        return NULL;
    }
    PyObject *result = _PyCFunction_TrampolineCall(
        meth, PyCFunction_GET_SELF(func), NULL);
    _Py_LeaveRecursiveCallTstate(tstate);
    return result;
}

static PyObject *
cfunction_vectorcall_O(
    PyObject *func, PyObject *const *args, size_t nargsf, PyObject *kwnames)
{
    PyThreadState *tstate = _PyThreadState_GET();
    if (cfunction_check_kwargs(tstate, func, kwnames)) {
        return NULL;
    }
    Py_ssize_t nargs = PyVectorcall_NARGS(nargsf);
    if (nargs != 1) {
        PyObject *funcstr = _PyObject_FunctionStr(func);
        if (funcstr != NULL) {
            _PyErr_Format(tstate, PyExc_TypeError,
                "%U takes exactly one argument (%zd given)", funcstr, nargs);
            Py_DECREF(funcstr);
        }
        return NULL;
    }
    PyCFunction meth = (PyCFunction)cfunction_enter_call(tstate, func);
    if (meth == NULL) {
        return NULL;
    }
    PyObject *result = _PyCFunction_TrampolineCall(
        meth, PyCFunction_GET_SELF(func), args[0]);
    _Py_LeaveRecursiveCallTstate(tstate);
    return result;
}


static PyObject *
cfunction_call(PyObject *func, PyObject *args, PyObject *kwargs)
{
    assert(kwargs == NULL || PyDict_Check(kwargs));

    PyThreadState *tstate = _PyThreadState_GET();
    assert(!_PyErr_Occurred(tstate));

    int flags = PyCFunction_GET_FLAGS(func);
    if (!(flags & METH_VARARGS)) {
        /* If this is not a METH_VARARGS function, delegate to vectorcall */
        return PyVectorcall_Call(func, args, kwargs);
    }

    /* For METH_VARARGS, we cannot use vectorcall as the vectorcall pointer
     * is NULL. This is intentional, since vectorcall would be slower. */
    PyCFunction meth = PyCFunction_GET_FUNCTION(func);
    PyObject *self = PyCFunction_GET_SELF(func);

    PyObject *result;
    if (flags & METH_KEYWORDS) {
        result = _PyCFunctionWithKeywords_TrampolineCall(
            (*(PyCFunctionWithKeywords)(void(*)(void))meth),
            self, args, kwargs);
    }
    else {
        if (kwargs != NULL && PyDict_GET_SIZE(kwargs) != 0) {
            _PyErr_Format(tstate, PyExc_TypeError,
                          "%.200s() takes no keyword arguments",
                          ((PyCFunctionObject*)func)->m_ml->ml_name);
            return NULL;
        }
        result = _PyCFunction_TrampolineCall(meth, self, args);
    }
    return _Py_CheckFunctionResult(tstate, func, result, NULL);
}

#if defined(__EMSCRIPTEN__) && defined(PY_CALL_TRAMPOLINE)
#error #include <emscripten.h>

EM_JS(PyObject*, _PyCFunctionWithKeywords_TrampolineCall, (PyCFunctionWithKeywords func, PyObject *self, PyObject *args, PyObject *kw), {
    return wasmTable.get(func)(self, args, kw);
});
#endif