1
2 /* Method object implementation */
3
4 #include "Python.h"
5 #include "internal/mem.h"
6 #include "internal/pystate.h"
7 #include "structmember.h"
8
9 /* Free list for method objects to safe malloc/free overhead
10 * The m_self element is used to chain the objects.
11 */
12 static PyCFunctionObject *free_list = NULL;
13 static int numfree = 0;
14 #ifndef PyCFunction_MAXFREELIST
15 #define PyCFunction_MAXFREELIST 256
16 #endif
17
18 /* undefine macro trampoline to PyCFunction_NewEx */
19 #undef PyCFunction_New
20
21 PyAPI_FUNC(PyObject *)
PyCFunction_New(PyMethodDef * ml,PyObject * self)22 PyCFunction_New(PyMethodDef *ml, PyObject *self)
23 {
24 return PyCFunction_NewEx(ml, self, NULL);
25 }
26
27 PyObject *
PyCFunction_NewEx(PyMethodDef * ml,PyObject * self,PyObject * module)28 PyCFunction_NewEx(PyMethodDef *ml, PyObject *self, PyObject *module)
29 {
30 PyCFunctionObject *op;
31 op = free_list;
32 if (op != NULL) {
33 free_list = (PyCFunctionObject *)(op->m_self);
34 (void)PyObject_INIT(op, &PyCFunction_Type);
35 numfree--;
36 }
37 else {
38 op = PyObject_GC_New(PyCFunctionObject, &PyCFunction_Type);
39 if (op == NULL)
40 return NULL;
41 }
42 op->m_weakreflist = NULL;
43 op->m_ml = ml;
44 Py_XINCREF(self);
45 op->m_self = self;
46 Py_XINCREF(module);
47 op->m_module = module;
48 _PyObject_GC_TRACK(op);
49 return (PyObject *)op;
50 }
51
52 PyCFunction
PyCFunction_GetFunction(PyObject * op)53 PyCFunction_GetFunction(PyObject *op)
54 {
55 if (!PyCFunction_Check(op)) {
56 PyErr_BadInternalCall();
57 return NULL;
58 }
59 return PyCFunction_GET_FUNCTION(op);
60 }
61
62 PyObject *
PyCFunction_GetSelf(PyObject * op)63 PyCFunction_GetSelf(PyObject *op)
64 {
65 if (!PyCFunction_Check(op)) {
66 PyErr_BadInternalCall();
67 return NULL;
68 }
69 return PyCFunction_GET_SELF(op);
70 }
71
72 int
PyCFunction_GetFlags(PyObject * op)73 PyCFunction_GetFlags(PyObject *op)
74 {
75 if (!PyCFunction_Check(op)) {
76 PyErr_BadInternalCall();
77 return -1;
78 }
79 return PyCFunction_GET_FLAGS(op);
80 }
81
82 /* Methods (the standard built-in methods, that is) */
83
84 static void
meth_dealloc(PyCFunctionObject * m)85 meth_dealloc(PyCFunctionObject *m)
86 {
87 _PyObject_GC_UNTRACK(m);
88 if (m->m_weakreflist != NULL) {
89 PyObject_ClearWeakRefs((PyObject*) m);
90 }
91 Py_XDECREF(m->m_self);
92 Py_XDECREF(m->m_module);
93 if (numfree < PyCFunction_MAXFREELIST) {
94 m->m_self = (PyObject *)free_list;
95 free_list = m;
96 numfree++;
97 }
98 else {
99 PyObject_GC_Del(m);
100 }
101 }
102
103 static PyObject *
meth_reduce(PyCFunctionObject * m)104 meth_reduce(PyCFunctionObject *m)
105 {
106 _Py_IDENTIFIER(getattr);
107
108 if (m->m_self == NULL || PyModule_Check(m->m_self))
109 return PyUnicode_FromString(m->m_ml->ml_name);
110
111 return Py_BuildValue("N(Os)", _PyEval_GetBuiltinId(&PyId_getattr),
112 m->m_self, m->m_ml->ml_name);
113 }
114
115 static PyMethodDef meth_methods[] = {
116 {"__reduce__", (PyCFunction)meth_reduce, METH_NOARGS, NULL},
117 {NULL, NULL}
118 };
119
120 static PyObject *
meth_get__text_signature__(PyCFunctionObject * m,void * closure)121 meth_get__text_signature__(PyCFunctionObject *m, void *closure)
122 {
123 return _PyType_GetTextSignatureFromInternalDoc(m->m_ml->ml_name, m->m_ml->ml_doc);
124 }
125
126 static PyObject *
meth_get__doc__(PyCFunctionObject * m,void * closure)127 meth_get__doc__(PyCFunctionObject *m, void *closure)
128 {
129 return _PyType_GetDocFromInternalDoc(m->m_ml->ml_name, m->m_ml->ml_doc);
130 }
131
132 static PyObject *
meth_get__name__(PyCFunctionObject * m,void * closure)133 meth_get__name__(PyCFunctionObject *m, void *closure)
134 {
135 return PyUnicode_FromString(m->m_ml->ml_name);
136 }
137
138 static PyObject *
meth_get__qualname__(PyCFunctionObject * m,void * closure)139 meth_get__qualname__(PyCFunctionObject *m, void *closure)
140 {
141 /* If __self__ is a module or NULL, return m.__name__
142 (e.g. len.__qualname__ == 'len')
143
144 If __self__ is a type, return m.__self__.__qualname__ + '.' + m.__name__
145 (e.g. dict.fromkeys.__qualname__ == 'dict.fromkeys')
146
147 Otherwise return type(m.__self__).__qualname__ + '.' + m.__name__
148 (e.g. [].append.__qualname__ == 'list.append') */
149 PyObject *type, *type_qualname, *res;
150 _Py_IDENTIFIER(__qualname__);
151
152 if (m->m_self == NULL || PyModule_Check(m->m_self))
153 return PyUnicode_FromString(m->m_ml->ml_name);
154
155 type = PyType_Check(m->m_self) ? m->m_self : (PyObject*)Py_TYPE(m->m_self);
156
157 type_qualname = _PyObject_GetAttrId(type, &PyId___qualname__);
158 if (type_qualname == NULL)
159 return NULL;
160
161 if (!PyUnicode_Check(type_qualname)) {
162 PyErr_SetString(PyExc_TypeError, "<method>.__class__."
163 "__qualname__ is not a unicode object");
164 Py_XDECREF(type_qualname);
165 return NULL;
166 }
167
168 res = PyUnicode_FromFormat("%S.%s", type_qualname, m->m_ml->ml_name);
169 Py_DECREF(type_qualname);
170 return res;
171 }
172
173 static int
meth_traverse(PyCFunctionObject * m,visitproc visit,void * arg)174 meth_traverse(PyCFunctionObject *m, visitproc visit, void *arg)
175 {
176 Py_VISIT(m->m_self);
177 Py_VISIT(m->m_module);
178 return 0;
179 }
180
181 static PyObject *
meth_get__self__(PyCFunctionObject * m,void * closure)182 meth_get__self__(PyCFunctionObject *m, void *closure)
183 {
184 PyObject *self;
185
186 self = PyCFunction_GET_SELF(m);
187 if (self == NULL)
188 self = Py_None;
189 Py_INCREF(self);
190 return self;
191 }
192
193 static PyGetSetDef meth_getsets [] = {
194 {"__doc__", (getter)meth_get__doc__, NULL, NULL},
195 {"__name__", (getter)meth_get__name__, NULL, NULL},
196 {"__qualname__", (getter)meth_get__qualname__, NULL, NULL},
197 {"__self__", (getter)meth_get__self__, NULL, NULL},
198 {"__text_signature__", (getter)meth_get__text_signature__, NULL, NULL},
199 {0}
200 };
201
202 #define OFF(x) offsetof(PyCFunctionObject, x)
203
204 static PyMemberDef meth_members[] = {
205 {"__module__", T_OBJECT, OFF(m_module), PY_WRITE_RESTRICTED},
206 {NULL}
207 };
208
209 static PyObject *
meth_repr(PyCFunctionObject * m)210 meth_repr(PyCFunctionObject *m)
211 {
212 if (m->m_self == NULL || PyModule_Check(m->m_self))
213 return PyUnicode_FromFormat("<built-in function %s>",
214 m->m_ml->ml_name);
215 return PyUnicode_FromFormat("<built-in method %s of %s object at %p>",
216 m->m_ml->ml_name,
217 m->m_self->ob_type->tp_name,
218 m->m_self);
219 }
220
221 static PyObject *
meth_richcompare(PyObject * self,PyObject * other,int op)222 meth_richcompare(PyObject *self, PyObject *other, int op)
223 {
224 PyCFunctionObject *a, *b;
225 PyObject *res;
226 int eq;
227
228 if ((op != Py_EQ && op != Py_NE) ||
229 !PyCFunction_Check(self) ||
230 !PyCFunction_Check(other))
231 {
232 Py_RETURN_NOTIMPLEMENTED;
233 }
234 a = (PyCFunctionObject *)self;
235 b = (PyCFunctionObject *)other;
236 eq = a->m_self == b->m_self;
237 if (eq)
238 eq = a->m_ml->ml_meth == b->m_ml->ml_meth;
239 if (op == Py_EQ)
240 res = eq ? Py_True : Py_False;
241 else
242 res = eq ? Py_False : Py_True;
243 Py_INCREF(res);
244 return res;
245 }
246
247 static Py_hash_t
meth_hash(PyCFunctionObject * a)248 meth_hash(PyCFunctionObject *a)
249 {
250 Py_hash_t x, y;
251 if (a->m_self == NULL)
252 x = 0;
253 else {
254 x = PyObject_Hash(a->m_self);
255 if (x == -1)
256 return -1;
257 }
258 y = _Py_HashPointer((void*)(a->m_ml->ml_meth));
259 if (y == -1)
260 return -1;
261 x ^= y;
262 if (x == -1)
263 x = -2;
264 return x;
265 }
266
267
268 PyTypeObject PyCFunction_Type = {
269 PyVarObject_HEAD_INIT(&PyType_Type, 0)
270 "builtin_function_or_method",
271 sizeof(PyCFunctionObject),
272 0,
273 (destructor)meth_dealloc, /* tp_dealloc */
274 0, /* tp_print */
275 0, /* tp_getattr */
276 0, /* tp_setattr */
277 0, /* tp_reserved */
278 (reprfunc)meth_repr, /* tp_repr */
279 0, /* tp_as_number */
280 0, /* tp_as_sequence */
281 0, /* tp_as_mapping */
282 (hashfunc)meth_hash, /* tp_hash */
283 PyCFunction_Call, /* tp_call */
284 0, /* tp_str */
285 PyObject_GenericGetAttr, /* tp_getattro */
286 0, /* tp_setattro */
287 0, /* tp_as_buffer */
288 Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,/* tp_flags */
289 0, /* tp_doc */
290 (traverseproc)meth_traverse, /* tp_traverse */
291 0, /* tp_clear */
292 meth_richcompare, /* tp_richcompare */
293 offsetof(PyCFunctionObject, m_weakreflist), /* tp_weaklistoffset */
294 0, /* tp_iter */
295 0, /* tp_iternext */
296 meth_methods, /* tp_methods */
297 meth_members, /* tp_members */
298 meth_getsets, /* tp_getset */
299 0, /* tp_base */
300 0, /* tp_dict */
301 };
302
303 /* Clear out the free list */
304
305 int
PyCFunction_ClearFreeList(void)306 PyCFunction_ClearFreeList(void)
307 {
308 int freelist_size = numfree;
309
310 while (free_list) {
311 PyCFunctionObject *v = free_list;
312 free_list = (PyCFunctionObject *)(v->m_self);
313 PyObject_GC_Del(v);
314 numfree--;
315 }
316 assert(numfree == 0);
317 return freelist_size;
318 }
319
320 void
PyCFunction_Fini(void)321 PyCFunction_Fini(void)
322 {
323 (void)PyCFunction_ClearFreeList();
324 }
325
326 /* Print summary info about the state of the optimized allocator */
327 void
_PyCFunction_DebugMallocStats(FILE * out)328 _PyCFunction_DebugMallocStats(FILE *out)
329 {
330 _PyDebugAllocatorStats(out,
331 "free PyCFunctionObject",
332 numfree, sizeof(PyCFunctionObject));
333 }
334