PyObjectDir27.inc

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/* Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
2011, 2012, 2013, 2014 Python Software Foundation; All Rights Reserved
 
Copied from Objects/object.c under the PSF License Version 2.
 
PYTHON SOFTWARE FOUNDATION LICENSE VERSION 2
--------------------------------------------
 
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("PSF"), and the Individual or Organization ("Licensee") accessing and
otherwise using this software ("Python") in source or binary form and
its associated documentation.
 
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analyze, test, perform and/or display publicly, prepare derivative works,
distribute, and otherwise use Python alone or in any derivative version,
provided, however, that PSF's License Agreement and PSF's notice of copyright,
i.e., "Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
2011, 2012, 2013, 2014 Python Software Foundation; All Rights Reserved" are retained
in Python alone or in any derivative version prepared by Licensee.
 
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or incorporates Python or any part thereof, and wants to make
the derivative work available to others as provided herein, then
Licensee hereby agrees to include in any such work a brief summary of
the changes made to Python.
 
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*/
 
/* Helper for PyObject_Dir.
   Merge the __dict__ of aclass into dict, and recursively also all
   the __dict__s of aclass's base classes.  The order of merging isn't
   defined, as it's expected that only the final set of dict keys is
   interesting.
   Return 0 on success, -1 on error.
*/
 
static int merge_class_dict(PyObject* dict, PyObject* aclass)
{
    PyObject *classdict;
    PyObject *bases;
 
    assert(PyDict_Check(dict));
    assert(aclass);
 
    /* Merge in the type's dict (if any). */
    classdict = PyObject_GetAttrString(aclass, "__dict__");
    if (classdict == NULL)
        PyErr_Clear();
    else {
        int status = PyDict_Update(dict, classdict);
        Py_DECREF(classdict);
        if (status < 0)
            return -1;
    }
 
    /* Recursively merge in the base types' (if any) dicts. */
    bases = PyObject_GetAttrString(aclass, "__bases__");
    if (bases == NULL)
        PyErr_Clear();
    else {
        /* We have no guarantee that bases is a real tuple */
        Py_ssize_t i, n;
        n = PySequence_Size(bases); /* This better be right */
        if (n < 0)
            PyErr_Clear();
        else {
            for (i = 0; i < n; i++) {
                int status;
                PyObject *base = PySequence_GetItem(bases, i);
                if (base == NULL) {
                    Py_DECREF(bases);
                    return -1;
                }
                status = merge_class_dict(dict, base);
                Py_DECREF(base);
                if (status < 0) {
                    Py_DECREF(bases);
                    return -1;
                }
            }
        }
        Py_DECREF(bases);
    }
    return 0;
}
 
/* Helper for PyObject_Dir of type objects: returns __dict__ and __bases__.
   We deliberately don't suck up its __class__, as methods belonging to the
   metaclass would probably be more confusing than helpful.
*/
static PyObject *
_specialized_dir_type(PyObject *obj)
{
    PyObject *result = NULL;
    PyObject *dict = PyDict_New();
 
    if (dict != NULL && merge_class_dict(dict, obj) == 0)
        result = PyDict_Keys(dict);
 
    Py_XDECREF(dict);
    return result;
}
 
static PyObject* _generic_dir(PyObject *obj)
{
  if (PyType_Check(obj))
    return _specialized_dir_type(obj);
 
  PyObject* result = NULL;
  PyObject* dict = NULL;
  PyObject* itsclass = NULL;
 
  /* Get __dict__ (which may or may not be a real dict...) */
  dict = PyObject_GetAttrString(obj, "__dict__");
  if (dict == NULL) {
    PyErr_Clear();
    dict = PyDict_New();
  } else if (!PyDict_Check(dict)) {
    Py_DECREF(dict);
    dict = PyDict_New();
  } else {
    /* Copy __dict__ to avoid mutating it. */
    PyObject* temp = PyDict_Copy(dict);
    Py_DECREF(dict);
    dict = temp;
  }
 
    if (dict == NULL)
        goto error;
 
    /* Merge in attrs reachable from its class. */
    itsclass = PyObject_GetAttrString(obj, "__class__");
    if (itsclass == NULL)
        /* XXX(tomer): Perhaps fall back to obj->ob_type if no
                       __class__ exists? */
        PyErr_Clear();
    else { 
        if (merge_class_dict(dict, itsclass) != 0)
            goto error;
    }
 
    result = PyDict_Keys(dict);
    /* fall through */
error:
    Py_XDECREF(itsclass);
    Py_XDECREF(dict);
    return result;
}