1 /* Boolean type, a subtype of int */
2
3 #include "Python.h"
4 #include "pycore_long.h" // FALSE_TAG TRUE_TAG
5 #include "pycore_modsupport.h" // _PyArg_NoKwnames()
6 #include "pycore_object.h" // _Py_FatalRefcountError()
7 #include "pycore_runtime.h" // _Py_ID()
8
9 #include <stddef.h>
10
11 /* We define bool_repr to return "False" or "True" */
12
13 static PyObject *
bool_repr(PyObject * self)14 bool_repr(PyObject *self)
15 {
16 return self == Py_True ? &_Py_ID(True) : &_Py_ID(False);
17 }
18
19 /* Function to return a bool from a C long */
20
PyBool_FromLong(long ok)21 PyObject *PyBool_FromLong(long ok)
22 {
23 return ok ? Py_True : Py_False;
24 }
25
26 /* We define bool_new to always return either Py_True or Py_False */
27
28 static PyObject *
bool_new(PyTypeObject * type,PyObject * args,PyObject * kwds)29 bool_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
30 {
31 PyObject *x = Py_False;
32 long ok;
33
34 if (!_PyArg_NoKeywords("bool", kwds))
35 return NULL;
36 if (!PyArg_UnpackTuple(args, "bool", 0, 1, &x))
37 return NULL;
38 ok = PyObject_IsTrue(x);
39 if (ok < 0)
40 return NULL;
41 return PyBool_FromLong(ok);
42 }
43
44 static PyObject *
bool_vectorcall(PyObject * type,PyObject * const * args,size_t nargsf,PyObject * kwnames)45 bool_vectorcall(PyObject *type, PyObject * const*args,
46 size_t nargsf, PyObject *kwnames)
47 {
48 long ok = 0;
49 if (!_PyArg_NoKwnames("bool", kwnames)) {
50 return NULL;
51 }
52
53 Py_ssize_t nargs = PyVectorcall_NARGS(nargsf);
54 if (!_PyArg_CheckPositional("bool", nargs, 0, 1)) {
55 return NULL;
56 }
57
58 assert(PyType_Check(type));
59 if (nargs) {
60 ok = PyObject_IsTrue(args[0]);
61 if (ok < 0) {
62 return NULL;
63 }
64 }
65 return PyBool_FromLong(ok);
66 }
67
68 /* Arithmetic operations redefined to return bool if both args are bool. */
69
70 static PyObject *
bool_invert(PyObject * v)71 bool_invert(PyObject *v)
72 {
73 if (PyErr_WarnEx(PyExc_DeprecationWarning,
74 "Bitwise inversion '~' on bool is deprecated and will be removed in "
75 "Python 3.16. This returns the bitwise inversion of the underlying int "
76 "object and is usually not what you expect from negating "
77 "a bool. Use the 'not' operator for boolean negation or "
78 "~int(x) if you really want the bitwise inversion of the "
79 "underlying int.",
80 1) < 0) {
81 return NULL;
82 }
83 return PyLong_Type.tp_as_number->nb_invert(v);
84 }
85
86 static PyObject *
bool_and(PyObject * a,PyObject * b)87 bool_and(PyObject *a, PyObject *b)
88 {
89 if (!PyBool_Check(a) || !PyBool_Check(b))
90 return PyLong_Type.tp_as_number->nb_and(a, b);
91 return PyBool_FromLong((a == Py_True) & (b == Py_True));
92 }
93
94 static PyObject *
bool_or(PyObject * a,PyObject * b)95 bool_or(PyObject *a, PyObject *b)
96 {
97 if (!PyBool_Check(a) || !PyBool_Check(b))
98 return PyLong_Type.tp_as_number->nb_or(a, b);
99 return PyBool_FromLong((a == Py_True) | (b == Py_True));
100 }
101
102 static PyObject *
bool_xor(PyObject * a,PyObject * b)103 bool_xor(PyObject *a, PyObject *b)
104 {
105 if (!PyBool_Check(a) || !PyBool_Check(b))
106 return PyLong_Type.tp_as_number->nb_xor(a, b);
107 return PyBool_FromLong((a == Py_True) ^ (b == Py_True));
108 }
109
110 /* Doc string */
111
112 PyDoc_STRVAR(bool_doc,
113 "bool(object=False, /)\n\
114 --\n\
115 \n\
116 Returns True when the argument is true, False otherwise.\n\
117 The builtins True and False are the only two instances of the class bool.\n\
118 The class bool is a subclass of the class int, and cannot be subclassed.");
119
120 /* Arithmetic methods -- only so we can override &, |, ^. */
121
122 static PyNumberMethods bool_as_number = {
123 0, /* nb_add */
124 0, /* nb_subtract */
125 0, /* nb_multiply */
126 0, /* nb_remainder */
127 0, /* nb_divmod */
128 0, /* nb_power */
129 0, /* nb_negative */
130 0, /* nb_positive */
131 0, /* nb_absolute */
132 0, /* nb_bool */
133 (unaryfunc)bool_invert, /* nb_invert */
134 0, /* nb_lshift */
135 0, /* nb_rshift */
136 bool_and, /* nb_and */
137 bool_xor, /* nb_xor */
138 bool_or, /* nb_or */
139 0, /* nb_int */
140 0, /* nb_reserved */
141 0, /* nb_float */
142 0, /* nb_inplace_add */
143 0, /* nb_inplace_subtract */
144 0, /* nb_inplace_multiply */
145 0, /* nb_inplace_remainder */
146 0, /* nb_inplace_power */
147 0, /* nb_inplace_lshift */
148 0, /* nb_inplace_rshift */
149 0, /* nb_inplace_and */
150 0, /* nb_inplace_xor */
151 0, /* nb_inplace_or */
152 0, /* nb_floor_divide */
153 0, /* nb_true_divide */
154 0, /* nb_inplace_floor_divide */
155 0, /* nb_inplace_true_divide */
156 0, /* nb_index */
157 };
158
159 static void
bool_dealloc(PyObject * boolean)160 bool_dealloc(PyObject *boolean)
161 {
162 /* This should never get called, but we also don't want to SEGV if
163 * we accidentally decref Booleans out of existence. Instead,
164 * since bools are immortal, re-set the reference count.
165 */
166 _Py_SetImmortal(boolean);
167 }
168
169 /* The type object for bool. Note that this cannot be subclassed! */
170
171 PyTypeObject PyBool_Type = {
172 PyVarObject_HEAD_INIT(&PyType_Type, 0)
173 "bool",
174 offsetof(struct _longobject, long_value.ob_digit), /* tp_basicsize */
175 sizeof(digit), /* tp_itemsize */
176 bool_dealloc, /* tp_dealloc */
177 0, /* tp_vectorcall_offset */
178 0, /* tp_getattr */
179 0, /* tp_setattr */
180 0, /* tp_as_async */
181 bool_repr, /* tp_repr */
182 &bool_as_number, /* tp_as_number */
183 0, /* tp_as_sequence */
184 0, /* tp_as_mapping */
185 0, /* tp_hash */
186 0, /* tp_call */
187 0, /* tp_str */
188 0, /* tp_getattro */
189 0, /* tp_setattro */
190 0, /* tp_as_buffer */
191 Py_TPFLAGS_DEFAULT, /* tp_flags */
192 bool_doc, /* tp_doc */
193 0, /* tp_traverse */
194 0, /* tp_clear */
195 0, /* tp_richcompare */
196 0, /* tp_weaklistoffset */
197 0, /* tp_iter */
198 0, /* tp_iternext */
199 0, /* tp_methods */
200 0, /* tp_members */
201 0, /* tp_getset */
202 &PyLong_Type, /* tp_base */
203 0, /* tp_dict */
204 0, /* tp_descr_get */
205 0, /* tp_descr_set */
206 0, /* tp_dictoffset */
207 0, /* tp_init */
208 0, /* tp_alloc */
209 bool_new, /* tp_new */
210 .tp_vectorcall = bool_vectorcall,
211 };
212
213 /* The objects representing bool values False and True */
214
215 struct _longobject _Py_FalseStruct = {
216 PyObject_HEAD_INIT(&PyBool_Type)
217 { .lv_tag = _PyLong_FALSE_TAG,
218 { 0 }
219 }
220 };
221
222 struct _longobject _Py_TrueStruct = {
223 PyObject_HEAD_INIT(&PyBool_Type)
224 { .lv_tag = _PyLong_TRUE_TAG,
225 { 1 }
226 }
227 };
228