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/Objects/methodobject.c b/Objects/methodobject.c
index 5818616..3a205f5 100644
--- a/Objects/methodobject.c
+++ b/Objects/methodobject.c
@@ -132,7 +132,7 @@
static PyObject *
meth_get__doc__(PyCFunctionObject *m, void *closure)
{
- char *doc = m->m_ml->ml_doc;
+ const char *doc = m->m_ml->ml_doc;
if (doc != NULL)
return PyString_FromString(doc);
@@ -311,13 +311,13 @@
/* Find a method in a method chain */
PyObject *
-Py_FindMethodInChain(PyMethodChain *chain, PyObject *self, char *name)
+Py_FindMethodInChain(PyMethodChain *chain, PyObject *self, const char *name)
{
if (name[0] == '_' && name[1] == '_') {
if (strcmp(name, "__methods__") == 0)
return listmethodchain(chain);
if (strcmp(name, "__doc__") == 0) {
- char *doc = self->ob_type->tp_doc;
+ const char *doc = self->ob_type->tp_doc;
if (doc != NULL)
return PyString_FromString(doc);
}
@@ -339,7 +339,7 @@
/* Find a method in a single method list */
PyObject *
-Py_FindMethod(PyMethodDef *methods, PyObject *self, char *name)
+Py_FindMethod(PyMethodDef *methods, PyObject *self, const char *name)
{
PyMethodChain chain;
chain.methods = methods;