Add const to several API functions that take char *.
In C++, it's an error to pass a string literal to a char* function
without a const_cast(). Rather than require every C++ extension
module to put a cast around string literals, fix the API to state the
const-ness.
I focused on parts of the API where people usually pass literals:
PyArg_ParseTuple() and friends, Py_BuildValue(), PyMethodDef, the type
slots, etc. Predictably, there were a large set of functions that
needed to be fixed as a result of these changes. The most pervasive
change was to make the keyword args list passed to
PyArg_ParseTupleAndKewords() to be a const char *kwlist[].
One cast was required as a result of the changes: A type object
mallocs the memory for its tp_doc slot and later frees it.
PyTypeObject says that tp_doc is const char *; but if the type was
created by type_new(), we know it is safe to cast to char *.
diff --git a/Python/import.c b/Python/import.c
index fcdc46b..daa8f8d 100644
--- a/Python/import.c
+++ b/Python/import.c
@@ -555,7 +555,7 @@
'NEW' REFERENCE! */
PyObject *
-PyImport_AddModule(char *name)
+PyImport_AddModule(const char *name)
{
PyObject *modules = PyImport_GetModuleDict();
PyObject *m;
@@ -1875,7 +1875,7 @@
its module object WITH INCREMENTED REFERENCE COUNT */
PyObject *
-PyImport_ImportModule(char *name)
+PyImport_ImportModule(const char *name)
{
PyObject *pname;
PyObject *result;