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
|
/* Cell object implementation */
#include "Python.h"
PyObject *
PyCell_New(PyObject *obj)
{
PyCellObject *op;
op = (PyCellObject *)PyObject_GC_New(PyCellObject, &PyCell_Type);
if (op == NULL)
return NULL;
op->ob_ref = obj;
Py_XINCREF(obj);
_PyObject_GC_TRACK(op);
return (PyObject *)op;
}
PyObject *
PyCell_Get(PyObject *op)
{
if (!PyCell_Check(op)) {
PyErr_BadInternalCall();
return NULL;
}
Py_XINCREF(((PyCellObject*)op)->ob_ref);
return PyCell_GET(op);
}
int
PyCell_Set(PyObject *op, PyObject *obj)
{
PyObject* oldobj;
if (!PyCell_Check(op)) {
PyErr_BadInternalCall();
return -1;
}
oldobj = PyCell_GET(op);
Py_XINCREF(obj);
PyCell_SET(op, obj);
Py_XDECREF(oldobj);
return 0;
}
static void
cell_dealloc(PyCellObject *op)
{
_PyObject_GC_UNTRACK(op);
Py_XDECREF(op->ob_ref);
PyObject_GC_Del(op);
}
#define TEST_COND(cond) ((cond) ? Py_True : Py_False)
static PyObject *
cell_richcompare(PyObject *a, PyObject *b, int op)
{
int result;
PyObject *v;
/* neither argument should be NULL, unless something's gone wrong */
assert(a != NULL && b != NULL);
/* both arguments should be instances of PyCellObject */
if (!PyCell_Check(a) || !PyCell_Check(b)) {
v = Py_NotImplemented;
Py_INCREF(v);
return v;
}
/* compare cells by contents; empty cells come before anything else */
a = ((PyCellObject *)a)->ob_ref;
b = ((PyCellObject *)b)->ob_ref;
if (a != NULL && b != NULL)
return PyObject_RichCompare(a, b, op);
result = (b == NULL) - (a == NULL);
switch (op) {
case Py_EQ:
v = TEST_COND(result == 0);
break;
case Py_NE:
v = TEST_COND(result != 0);
break;
case Py_LE:
v = TEST_COND(result <= 0);
break;
case Py_GE:
v = TEST_COND(result >= 0);
break;
case Py_LT:
v = TEST_COND(result < 0);
break;
case Py_GT:
v = TEST_COND(result > 0);
break;
default:
PyErr_BadArgument();
return NULL;
}
Py_INCREF(v);
return v;
}
static PyObject *
cell_repr(PyCellObject *op)
{
if (op->ob_ref == NULL)
return PyUnicode_FromFormat("<cell at %p: empty>", op);
return PyUnicode_FromFormat("<cell at %p: %.80s object at %p>",
op, op->ob_ref->ob_type->tp_name,
op->ob_ref);
}
static int
cell_traverse(PyCellObject *op, visitproc visit, void *arg)
{
Py_VISIT(op->ob_ref);
return 0;
}
static int
cell_clear(PyCellObject *op)
{
Py_CLEAR(op->ob_ref);
return 0;
}
static PyObject *
cell_get_contents(PyCellObject *op, void *closure)
{
if (op->ob_ref == NULL)
{
PyErr_SetString(PyExc_ValueError, "Cell is empty");
return NULL;
}
Py_INCREF(op->ob_ref);
return op->ob_ref;
}
static PyGetSetDef cell_getsetlist[] = {
{"cell_contents", (getter)cell_get_contents, NULL},
{NULL} /* sentinel */
};
PyTypeObject PyCell_Type = {
PyVarObject_HEAD_INIT(&PyType_Type, 0)
"cell",
sizeof(PyCellObject),
0,
(destructor)cell_dealloc, /* tp_dealloc */
0, /* tp_print */
0, /* tp_getattr */
0, /* tp_setattr */
0, /* tp_reserved */
(reprfunc)cell_repr, /* tp_repr */
0, /* tp_as_number */
0, /* tp_as_sequence */
0, /* tp_as_mapping */
0, /* tp_hash */
0, /* tp_call */
0, /* tp_str */
PyObject_GenericGetAttr, /* tp_getattro */
0, /* tp_setattro */
0, /* tp_as_buffer */
Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC,/* tp_flags */
0, /* tp_doc */
(traverseproc)cell_traverse, /* tp_traverse */
(inquiry)cell_clear, /* tp_clear */
cell_richcompare, /* tp_richcompare */
0, /* tp_weaklistoffset */
0, /* tp_iter */
0, /* tp_iternext */
0, /* tp_methods */
0, /* tp_members */
cell_getsetlist, /* tp_getset */
};
|