Add memcached_clone support.

_pylibmcmodule.c

@@ -745,6 +745,21 @@ static PyObject *PylibMC_Client_disconnect_all(PylibMC_Client *self) {
     memcached_quit(self->mc);
     Py_RETURN_NONE;
 }
+
+static PyObject *PylibMC_Client_clone(PylibMC_Client *self) {
+    PylibMC_Client *new_self;
+
+    /* XXX Is it really wise to short-circuit like this? I don't see a problem
+     * with it. */
+    new_self = (PylibMC_Client *)self->ob_type->tp_new(self->ob_type, NULL, NULL);
+    if (new_self == NULL) {
+        return NULL;
+    }
+    memset(new_self->mc, 0, sizeof(memcached_st));
+    new_self->mc = memcached_clone(new_self->mc, self->mc);
+
+    return (PyObject *)new_self;
+}
 /* }}} */
 
 static PyObject *PylibMC_ErrFromMemcached(PylibMC_Client *self, const char *what,

_pylibmcmodule.h

@@ -149,6 +149,7 @@ static PyObject *PylibMC_Client_get_behaviors(PylibMC_Client *);
 static PyObject *PylibMC_Client_set_behaviors(PylibMC_Client *, PyObject *);
 static PyObject *PylibMC_Client_flush_all(PylibMC_Client *, PyObject *, PyObject *);
 static PyObject *PylibMC_Client_disconnect_all(PylibMC_Client *);
+static PyObject *PylibMC_Client_clone(PylibMC_Client *);
 static PyObject *PylibMC_ErrFromMemcached(PylibMC_Client *, const char *,
         memcached_return);
 static PyObject *_PylibMC_Unpickle(const char *, size_t);
@@ -191,6 +192,9 @@ static PyMethodDef PylibMC_ClientType_methods[] = {
         METH_VARARGS|METH_KEYWORDS, "Flush all data on all servers."},
     {"disconnect_all", (PyCFunction)PylibMC_Client_disconnect_all, METH_NOARGS,
         "Disconnect from all servers and reset own state."},
+    {"clone", (PyCFunction)PylibMC_Client_clone, METH_NOARGS,
+        "Clone this client entirely such that it is safe to access from "
+        "another thread. This creates a new connection."},
     {NULL, NULL, 0, NULL}
 };
 /* }}} */

tests.py

@@ -116,6 +116,17 @@ True
 >>> c.get("tengil").bar == bla.bar
 True
 
+Cloning (ethically, I don't know about it.)
+>>> c is not c.clone()
+True
+>>> c2 = c.clone()
+>>> c.set("test", "hello")
+True
+>>> c2.get("test")
+'hello'
+>>> c2.delete("test")
+True
+>>> del c2
 
 Behaviors.
 >>> c.set_behaviors({"tcp_nodelay": True, "hash": 6})