1 // namespace object implementation
2 
3 #include "Python.h"
4 #include "pycore_namespace.h"     // _PyNamespace_Type
5 #include "structmember.h"         // PyMemberDef
6 
7 
8 typedef struct {
9     PyObject_HEAD
10     PyObject *ns_dict;
11 } _PyNamespaceObject;
12 
13 
14 static PyMemberDef namespace_members[] = {
15     {"__dict__", T_OBJECT, offsetof(_PyNamespaceObject, ns_dict), READONLY},
16     {NULL}
17 };
18 
19 
20 // Methods
21 
22 static PyObject *
namespace_new(PyTypeObject * type,PyObject * args,PyObject * kwds)23 namespace_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
24 {
25     PyObject *self;
26 
27     assert(type != NULL && type->tp_alloc != NULL);
28     self = type->tp_alloc(type, 0);
29     if (self != NULL) {
30         _PyNamespaceObject *ns = (_PyNamespaceObject *)self;
31         ns->ns_dict = PyDict_New();
32         if (ns->ns_dict == NULL) {
33             Py_DECREF(ns);
34             return NULL;
35         }
36     }
37     return self;
38 }
39 
40 
41 static int
namespace_init(_PyNamespaceObject * ns,PyObject * args,PyObject * kwds)42 namespace_init(_PyNamespaceObject *ns, PyObject *args, PyObject *kwds)
43 {
44     if (PyTuple_GET_SIZE(args) != 0) {
45         PyErr_Format(PyExc_TypeError, "no positional arguments expected");
46         return -1;
47     }
48     if (kwds == NULL) {
49         return 0;
50     }
51     if (!PyArg_ValidateKeywordArguments(kwds)) {
52         return -1;
53     }
54     return PyDict_Update(ns->ns_dict, kwds);
55 }
56 
57 
58 static void
namespace_dealloc(_PyNamespaceObject * ns)59 namespace_dealloc(_PyNamespaceObject *ns)
60 {
61     PyObject_GC_UnTrack(ns);
62     Py_CLEAR(ns->ns_dict);
63     Py_TYPE(ns)->tp_free((PyObject *)ns);
64 }
65 
66 
67 static PyObject *
namespace_repr(PyObject * ns)68 namespace_repr(PyObject *ns)
69 {
70     int i, loop_error = 0;
71     PyObject *pairs = NULL, *d = NULL, *keys = NULL, *keys_iter = NULL;
72     PyObject *key;
73     PyObject *separator, *pairsrepr, *repr = NULL;
74     const char * name;
75 
76     name = Py_IS_TYPE(ns, &_PyNamespace_Type) ? "namespace"
77                                                : Py_TYPE(ns)->tp_name;
78 
79     i = Py_ReprEnter(ns);
80     if (i != 0) {
81         return i > 0 ? PyUnicode_FromFormat("%s(...)", name) : NULL;
82     }
83 
84     pairs = PyList_New(0);
85     if (pairs == NULL)
86         goto error;
87 
88     d = ((_PyNamespaceObject *)ns)->ns_dict;
89     assert(d != NULL);
90     Py_INCREF(d);
91 
92     keys = PyDict_Keys(d);
93     if (keys == NULL)
94         goto error;
95 
96     keys_iter = PyObject_GetIter(keys);
97     if (keys_iter == NULL)
98         goto error;
99 
100     while ((key = PyIter_Next(keys_iter)) != NULL) {
101         if (PyUnicode_Check(key) && PyUnicode_GET_LENGTH(key) > 0) {
102             PyObject *value, *item;
103 
104             value = PyDict_GetItemWithError(d, key);
105             if (value != NULL) {
106                 item = PyUnicode_FromFormat("%U=%R", key, value);
107                 if (item == NULL) {
108                     loop_error = 1;
109                 }
110                 else {
111                     loop_error = PyList_Append(pairs, item);
112                     Py_DECREF(item);
113                 }
114             }
115             else if (PyErr_Occurred()) {
116                 loop_error = 1;
117             }
118         }
119 
120         Py_DECREF(key);
121         if (loop_error)
122             goto error;
123     }
124 
125     separator = PyUnicode_FromString(", ");
126     if (separator == NULL)
127         goto error;
128 
129     pairsrepr = PyUnicode_Join(separator, pairs);
130     Py_DECREF(separator);
131     if (pairsrepr == NULL)
132         goto error;
133 
134     repr = PyUnicode_FromFormat("%s(%S)", name, pairsrepr);
135     Py_DECREF(pairsrepr);
136 
137 error:
138     Py_XDECREF(pairs);
139     Py_XDECREF(d);
140     Py_XDECREF(keys);
141     Py_XDECREF(keys_iter);
142     Py_ReprLeave(ns);
143 
144     return repr;
145 }
146 
147 
148 static int
namespace_traverse(_PyNamespaceObject * ns,visitproc visit,void * arg)149 namespace_traverse(_PyNamespaceObject *ns, visitproc visit, void *arg)
150 {
151     Py_VISIT(ns->ns_dict);
152     return 0;
153 }
154 
155 
156 static int
namespace_clear(_PyNamespaceObject * ns)157 namespace_clear(_PyNamespaceObject *ns)
158 {
159     Py_CLEAR(ns->ns_dict);
160     return 0;
161 }
162 
163 
164 static PyObject *
namespace_richcompare(PyObject * self,PyObject * other,int op)165 namespace_richcompare(PyObject *self, PyObject *other, int op)
166 {
167     if (PyObject_TypeCheck(self, &_PyNamespace_Type) &&
168         PyObject_TypeCheck(other, &_PyNamespace_Type))
169         return PyObject_RichCompare(((_PyNamespaceObject *)self)->ns_dict,
170                                    ((_PyNamespaceObject *)other)->ns_dict, op);
171     Py_RETURN_NOTIMPLEMENTED;
172 }
173 
174 
175 PyDoc_STRVAR(namespace_reduce__doc__, "Return state information for pickling");
176 
177 static PyObject *
namespace_reduce(_PyNamespaceObject * ns,PyObject * Py_UNUSED (ignored))178 namespace_reduce(_PyNamespaceObject *ns, PyObject *Py_UNUSED(ignored))
179 {
180     PyObject *result, *args = PyTuple_New(0);
181 
182     if (!args)
183         return NULL;
184 
185     result = PyTuple_Pack(3, (PyObject *)Py_TYPE(ns), args, ns->ns_dict);
186     Py_DECREF(args);
187     return result;
188 }
189 
190 
191 static PyMethodDef namespace_methods[] = {
192     {"__reduce__", (PyCFunction)namespace_reduce, METH_NOARGS,
193      namespace_reduce__doc__},
194     {NULL,         NULL}  // sentinel
195 };
196 
197 
198 PyDoc_STRVAR(namespace_doc,
199 "A simple attribute-based namespace.\n\
200 \n\
201 SimpleNamespace(**kwargs)");
202 
203 PyTypeObject _PyNamespace_Type = {
204     PyVarObject_HEAD_INIT(&PyType_Type, 0)
205     "types.SimpleNamespace",                    /* tp_name */
206     sizeof(_PyNamespaceObject),                 /* tp_basicsize */
207     0,                                          /* tp_itemsize */
208     (destructor)namespace_dealloc,              /* tp_dealloc */
209     0,                                          /* tp_vectorcall_offset */
210     0,                                          /* tp_getattr */
211     0,                                          /* tp_setattr */
212     0,                                          /* tp_as_async */
213     (reprfunc)namespace_repr,                   /* tp_repr */
214     0,                                          /* tp_as_number */
215     0,                                          /* tp_as_sequence */
216     0,                                          /* tp_as_mapping */
217     0,                                          /* tp_hash */
218     0,                                          /* tp_call */
219     0,                                          /* tp_str */
220     PyObject_GenericGetAttr,                    /* tp_getattro */
221     PyObject_GenericSetAttr,                    /* tp_setattro */
222     0,                                          /* tp_as_buffer */
223     Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC |
224         Py_TPFLAGS_BASETYPE,                    /* tp_flags */
225     namespace_doc,                              /* tp_doc */
226     (traverseproc)namespace_traverse,           /* tp_traverse */
227     (inquiry)namespace_clear,                   /* tp_clear */
228     namespace_richcompare,                      /* tp_richcompare */
229     0,                                          /* tp_weaklistoffset */
230     0,                                          /* tp_iter */
231     0,                                          /* tp_iternext */
232     namespace_methods,                          /* tp_methods */
233     namespace_members,                          /* tp_members */
234     0,                                          /* tp_getset */
235     0,                                          /* tp_base */
236     0,                                          /* tp_dict */
237     0,                                          /* tp_descr_get */
238     0,                                          /* tp_descr_set */
239     offsetof(_PyNamespaceObject, ns_dict),      /* tp_dictoffset */
240     (initproc)namespace_init,                   /* tp_init */
241     PyType_GenericAlloc,                        /* tp_alloc */
242     (newfunc)namespace_new,                     /* tp_new */
243     PyObject_GC_Del,                            /* tp_free */
244 };
245 
246 
247 PyObject *
_PyNamespace_New(PyObject * kwds)248 _PyNamespace_New(PyObject *kwds)
249 {
250     PyObject *ns = namespace_new(&_PyNamespace_Type, NULL, NULL);
251     if (ns == NULL)
252         return NULL;
253 
254     if (kwds == NULL)
255         return ns;
256     if (PyDict_Update(((_PyNamespaceObject *)ns)->ns_dict, kwds) != 0) {
257         Py_DECREF(ns);
258         return NULL;
259     }
260 
261     return (PyObject *)ns;
262 }
263