AppPkg/Applications/Python/Python-2.7.10/Objects/boolobject.c

   1 /* Boolean type, a subtype of int */
   2
   3 #include "Python.h"
   4
   5 /* We need to define bool_print to override int_print */
   6
   7 static int
   8 bool_print(PyBoolObject *self, FILE *fp, int flags)
   9 {
  10     Py_BEGIN_ALLOW_THREADS
  11     fputs(self->ob_ival == 0 ? "False" : "True", fp);
  12     Py_END_ALLOW_THREADS
  13     return 0;
  14 }
  15
  16 /* We define bool_repr to return "False" or "True" */
  17
  18 static PyObject *false_str = NULL;
  19 static PyObject *true_str = NULL;
  20
  21 static PyObject *
  22 bool_repr(PyBoolObject *self)
  23 {
  24     PyObject *s;
  25
  26     if (self->ob_ival)
  27         s = true_str ? true_str :
  28             (true_str = PyString_InternFromString("True"));
  29     else
  30         s = false_str ? false_str :
  31             (false_str = PyString_InternFromString("False"));
  32     Py_XINCREF(s);
  33     return s;
  34 }
  35
  36 /* Function to return a bool from a C long */
  37
  38 PyObject *PyBool_FromLong(long ok)
  39 {
  40     PyObject *result;
  41
  42     if (ok)
  43         result = Py_True;
  44     else
  45         result = Py_False;
  46     Py_INCREF(result);
  47     return result;
  48 }
  49
  50 /* We define bool_new to always return either Py_True or Py_False */
  51
  52 static PyObject *
  53 bool_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
  54 {
  55     static char *kwlist[] = {"x", 0};
  56     PyObject *x = Py_False;
  57     long ok;
  58
  59     if (!PyArg_ParseTupleAndKeywords(args, kwds, "|O:bool", kwlist, &x))
  60         return NULL;
  61     ok = PyObject_IsTrue(x);
  62     if (ok < 0)
  63         return NULL;
  64     return PyBool_FromLong(ok);
  65 }
  66
  67 /* Arithmetic operations redefined to return bool if both args are bool. */
  68
  69 static PyObject *
  70 bool_and(PyObject *a, PyObject *b)
  71 {
  72     if (!PyBool_Check(a) || !PyBool_Check(b))
  73         return PyInt_Type.tp_as_number->nb_and(a, b);
  74     return PyBool_FromLong(
  75         ((PyBoolObject *)a)->ob_ival & ((PyBoolObject *)b)->ob_ival);
  76 }
  77
  78 static PyObject *
  79 bool_or(PyObject *a, PyObject *b)
  80 {
  81     if (!PyBool_Check(a) || !PyBool_Check(b))
  82         return PyInt_Type.tp_as_number->nb_or(a, b);
  83     return PyBool_FromLong(
  84         ((PyBoolObject *)a)->ob_ival | ((PyBoolObject *)b)->ob_ival);
  85 }
  86
  87 static PyObject *
  88 bool_xor(PyObject *a, PyObject *b)
  89 {
  90     if (!PyBool_Check(a) || !PyBool_Check(b))
  91         return PyInt_Type.tp_as_number->nb_xor(a, b);
  92     return PyBool_FromLong(
  93         ((PyBoolObject *)a)->ob_ival ^ ((PyBoolObject *)b)->ob_ival);
  94 }
  95
  96 /* Doc string */
  97
  98 PyDoc_STRVAR(bool_doc,
  99 "bool(x) -> bool\n\
 100 \n\
 101 Returns True when the argument x is true, False otherwise.\n\
 102 The builtins True and False are the only two instances of the class bool.\n\
 103 The class bool is a subclass of the class int, and cannot be subclassed.");
 104
 105 /* Arithmetic methods -- only so we can override &, |, ^. */
 106
 107 static PyNumberMethods bool_as_number = {
 108     0,                          /* nb_add */
 109     0,                          /* nb_subtract */
 110     0,                          /* nb_multiply */
 111     0,                          /* nb_divide */
 112     0,                          /* nb_remainder */
 113     0,                          /* nb_divmod */
 114     0,                          /* nb_power */
 115     0,                          /* nb_negative */
 116     0,                          /* nb_positive */
 117     0,                          /* nb_absolute */
 118     0,                          /* nb_nonzero */
 119     0,                          /* nb_invert */
 120     0,                          /* nb_lshift */
 121     0,                          /* nb_rshift */
 122     bool_and,                   /* nb_and */
 123     bool_xor,                   /* nb_xor */
 124     bool_or,                    /* nb_or */
 125     0,                          /* nb_coerce */
 126     0,                          /* nb_int */
 127     0,                          /* nb_long */
 128     0,                          /* nb_float */
 129     0,                          /* nb_oct */
 130     0,                          /* nb_hex */
 131     0,                          /* nb_inplace_add */
 132     0,                          /* nb_inplace_subtract */
 133     0,                          /* nb_inplace_multiply */
 134     0,                          /* nb_inplace_divide */
 135     0,                          /* nb_inplace_remainder */
 136     0,                          /* nb_inplace_power */
 137     0,                          /* nb_inplace_lshift */
 138     0,                          /* nb_inplace_rshift */
 139     0,                          /* nb_inplace_and */
 140     0,                          /* nb_inplace_xor */
 141     0,                          /* nb_inplace_or */
 142     0,                          /* nb_floor_divide */
 143     0,                          /* nb_true_divide */
 144     0,                          /* nb_inplace_floor_divide */
 145     0,                          /* nb_inplace_true_divide */
 146 };
 147
 148 /* The type object for bool.  Note that this cannot be subclassed! */
 149
 150 PyTypeObject PyBool_Type = {
 151     PyVarObject_HEAD_INIT(&PyType_Type, 0)
 152     "bool",
 153     sizeof(PyIntObject),
 154     0,
 155     0,                                          /* tp_dealloc */
 156     (printfunc)bool_print,                      /* tp_print */
 157     0,                                          /* tp_getattr */
 158     0,                                          /* tp_setattr */
 159     0,                                          /* tp_compare */
 160     (reprfunc)bool_repr,                        /* tp_repr */
 161     &bool_as_number,                            /* tp_as_number */
 162     0,                                          /* tp_as_sequence */
 163     0,                                          /* tp_as_mapping */
 164     0,                                          /* tp_hash */
 165     0,                                          /* tp_call */
 166     (reprfunc)bool_repr,                        /* tp_str */
 167     0,                                          /* tp_getattro */
 168     0,                                          /* tp_setattro */
 169     0,                                          /* tp_as_buffer */
 170     Py_TPFLAGS_DEFAULT | Py_TPFLAGS_CHECKTYPES, /* tp_flags */
 171     bool_doc,                                   /* tp_doc */
 172     0,                                          /* tp_traverse */
 173     0,                                          /* tp_clear */
 174     0,                                          /* tp_richcompare */
 175     0,                                          /* tp_weaklistoffset */
 176     0,                                          /* tp_iter */
 177     0,                                          /* tp_iternext */
 178     0,                                          /* tp_methods */
 179     0,                                          /* tp_members */
 180     0,                                          /* tp_getset */
 181     &PyInt_Type,                                /* tp_base */
 182     0,                                          /* tp_dict */
 183     0,                                          /* tp_descr_get */
 184     0,                                          /* tp_descr_set */
 185     0,                                          /* tp_dictoffset */
 186     0,                                          /* tp_init */
 187     0,                                          /* tp_alloc */
 188     bool_new,                                   /* tp_new */
 189 };
 190
 191 /* The objects representing bool values False and True */
 192
 193 /* Named Zero for link-level compatibility */
 194 PyIntObject _Py_ZeroStruct = {
 195     PyObject_HEAD_INIT(&PyBool_Type)
 196     0
 197 };
 198
 199 PyIntObject _Py_TrueStruct = {
 200     PyObject_HEAD_INIT(&PyBool_Type)
 201     1
 202 };