Cleanup import.c

* Replace PyUnicode_RPartition() with PyUnicode_FindChar() and
  PyUnicode_Substring() to avoid the creation of a temporary tuple.
* Use PyUnicode_FromFormat() to build a string and avoid the single_dot ('.')
  singleton

Thanks Serhiy Storchaka for your review.
This commit is contained in:
Victor Stinner 2016-05-20 11:36:13 +02:00
parent 03e6061956
commit 744c34e2ea

View file

@ -1349,7 +1349,6 @@ PyImport_ImportModuleLevelObject(PyObject *name, PyObject *given_globals,
_Py_IDENTIFIER(_find_and_load);
_Py_IDENTIFIER(_handle_fromlist);
_Py_IDENTIFIER(_lock_unlock_module);
_Py_static_string(single_dot, ".");
PyObject *abs_name = NULL;
PyObject *builtins_import = NULL;
PyObject *final_mod = NULL;
@ -1471,19 +1470,25 @@ PyImport_ImportModuleLevelObject(PyObject *name, PyObject *given_globals,
}
if (_PyDict_GetItemId(globals, &PyId___path__) == NULL) {
PyObject *partition = NULL;
PyObject *borrowed_dot = _PyUnicode_FromId(&single_dot);
if (borrowed_dot == NULL) {
Py_ssize_t dot;
if (PyUnicode_READY(package) < 0) {
goto error;
}
partition = PyUnicode_RPartition(package, borrowed_dot);
Py_DECREF(package);
if (partition == NULL) {
dot = PyUnicode_FindChar(package, '.',
0, PyUnicode_GET_LENGTH(package), -1);
if (dot == -2) {
goto error;
}
package = PyTuple_GET_ITEM(partition, 0);
Py_INCREF(package);
Py_DECREF(partition);
if (dot >= 0) {
PyObject *substr = PyUnicode_Substring(package, 0, dot);
if (substr == NULL) {
goto error;
}
Py_SETREF(package, substr);
}
}
}
@ -1531,17 +1536,8 @@ PyImport_ImportModuleLevelObject(PyObject *name, PyObject *given_globals,
goto error;
if (PyUnicode_GET_LENGTH(name) > 0) {
PyObject *borrowed_dot, *seq = NULL;
borrowed_dot = _PyUnicode_FromId(&single_dot);
seq = PyTuple_Pack(2, base, name);
abs_name = PyUnicode_FromFormat("%U.%U", base, name);
Py_DECREF(base);
if (borrowed_dot == NULL || seq == NULL) {
goto error;
}
abs_name = PyUnicode_Join(borrowed_dot, seq);
Py_DECREF(seq);
if (abs_name == NULL) {
goto error;
}
@ -1639,43 +1635,36 @@ PyImport_ImportModuleLevelObject(PyObject *name, PyObject *given_globals,
if (has_from < 0)
goto error;
if (!has_from) {
if (level == 0 || PyUnicode_GET_LENGTH(name) > 0) {
PyObject *front = NULL;
PyObject *partition = NULL;
PyObject *borrowed_dot = _PyUnicode_FromId(&single_dot);
Py_ssize_t len = PyUnicode_GET_LENGTH(name);
if (level == 0 || len > 0) {
Py_ssize_t dot;
if (borrowed_dot == NULL) {
dot = PyUnicode_FindChar(name, '.', 0, len, 1);
if (dot == -2) {
goto error;
}
partition = PyUnicode_Partition(name, borrowed_dot);
if (partition == NULL) {
goto error;
}
if (PyUnicode_GET_LENGTH(PyTuple_GET_ITEM(partition, 1)) == 0) {
if (dot == -1) {
/* No dot in module name, simple exit */
Py_DECREF(partition);
final_mod = mod;
Py_INCREF(mod);
goto error;
}
front = PyTuple_GET_ITEM(partition, 0);
Py_INCREF(front);
Py_DECREF(partition);
if (level == 0) {
PyObject *front = PyUnicode_Substring(name, 0, dot);
if (front == NULL) {
goto error;
}
final_mod = PyObject_CallFunctionObjArgs(builtins_import, front, NULL);
Py_DECREF(front);
}
else {
Py_ssize_t cut_off = PyUnicode_GET_LENGTH(name) -
PyUnicode_GET_LENGTH(front);
Py_ssize_t cut_off = len - dot;
Py_ssize_t abs_name_len = PyUnicode_GET_LENGTH(abs_name);
PyObject *to_return = PyUnicode_Substring(abs_name, 0,
abs_name_len - cut_off);
Py_DECREF(front);
if (to_return == NULL) {
goto error;
}