bpo-32436: Implement PEP 567 (#5027)

Modules/_contextvarsmodule.c

@@ -0,0 +1,75 @@
+#include "Python.h"
+
+#include "clinic/_contextvarsmodule.c.h"
+
+/*[clinic input]
+module _contextvars
+[clinic start generated code]*/
+/*[clinic end generated code: output=da39a3ee5e6b4b0d input=a0955718c8b8cea6]*/
+
+
+/*[clinic input]
+_contextvars.copy_context
+[clinic start generated code]*/
+
+static PyObject *
+_contextvars_copy_context_impl(PyObject *module)
+/*[clinic end generated code: output=1fcd5da7225c4fa9 input=89bb9ae485888440]*/
+{
+    return (PyObject *)PyContext_CopyCurrent();
+}
+
+
+PyDoc_STRVAR(module_doc, "Context Variables");
+
+static PyMethodDef _contextvars_methods[] = {
+    _CONTEXTVARS_COPY_CONTEXT_METHODDEF
+    {NULL, NULL}
+};
+
+static struct PyModuleDef _contextvarsmodule = {
+    PyModuleDef_HEAD_INIT,      /* m_base */
+    "_contextvars",             /* m_name */
+    module_doc,                 /* m_doc */
+    -1,                         /* m_size */
+    _contextvars_methods,       /* m_methods */
+    NULL,                       /* m_slots */
+    NULL,                       /* m_traverse */
+    NULL,                       /* m_clear */
+    NULL,                       /* m_free */
+};
+
+PyMODINIT_FUNC
+PyInit__contextvars(void)
+{
+    PyObject *m = PyModule_Create(&_contextvarsmodule);
+    if (m == NULL) {
+        return NULL;
+    }
+
+    Py_INCREF(&PyContext_Type);
+    if (PyModule_AddObject(m, "Context",
+                           (PyObject *)&PyContext_Type) < 0)
+    {
+        Py_DECREF(&PyContext_Type);
+        return NULL;
+    }
+
+    Py_INCREF(&PyContextVar_Type);
+    if (PyModule_AddObject(m, "ContextVar",
+                           (PyObject *)&PyContextVar_Type) < 0)
+    {
+        Py_DECREF(&PyContextVar_Type);
+        return NULL;
+    }
+
+    Py_INCREF(&PyContextToken_Type);
+    if (PyModule_AddObject(m, "Token",
+                           (PyObject *)&PyContextToken_Type) < 0)
+    {
+        Py_DECREF(&PyContextToken_Type);
+        return NULL;
+    }
+
+    return m;
+}