sbus: Refactor how we export DBus interfaces

Most importantly, stop using per connection private data. This doesn't
scale when you have more than one thing exporting or exported on a
connection.

Remove struct sbus_interface and expand sbus_conn_add_interface()
function. Remove various struct sbus_interface args to connection
initialization functions and make callers use sbus_conn_add_interface()
directly. The old method was optimized for exporting one interface
on a connection. We'll have connections that export zero, one or more
interfaces.

To export an interface on a DBus server, call sbus_conn_add_interface()
from within the sbus_server_conn_init_fn. To export an interface on
a DBus client, call sbus_conn_add_interface() after sbus_new_connection()
returns.

As before struct sbus_interface represents an object exported via DBus.
However it is now talloc allocated. One can set instance data on the
struct sbus_interface. This instance data is passed to the various
handlers and used in their implementation.

However, we now have type safe interface exporting in the various
high level sss_process_init() sss_monitor_init() and so on.

Introspection support was not in use, and is now gone until we
implement it using the metadata (future patch).

Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>
Reviewed-by: Pavel Březina <pbrezina@redhat.com>
Reviewed-by: Lukáš Slebodník <lslebodn@redhat.com>

1 files changed, 19 insertions, 13 deletions

diff --git a/src/sbus/sssd_dbus.h b/src/sbus/sssd_dbus.h
index dcb669079..ef728bd30 100644
--- a/src/sbus/sssd_dbus.h
+++ b/src/sbus/sssd_dbus.h
@@ -23,12 +23,13 @@
 #define _SSSD_DBUS_H_
 
 struct sbus_connection;
-
+struct sbus_interface;
 struct sbus_request;
 
 #include <dbus/dbus.h>
 
-typedef int (*sbus_msg_handler_fn)(struct sbus_request *dbus_req);
+typedef int (*sbus_msg_handler_fn)(struct sbus_request *dbus_req,
+                                   void *instance_data);
 
 /*
  * sbus_conn_destructor_fn
@@ -79,14 +80,28 @@ struct sbus_vtable {
 struct sbus_interface {
     const char *path;
     struct sbus_vtable *vtable;
-    sbus_msg_handler_fn introspect_fn;
+    void *instance_data;
 };
 
+/*
+ * Creates a new struct sbus_interface instance to be exported by a DBus
+ * service.
+ *
+ * Pass the result to sbus_conn_add_interface(). The interface
+ * will be exported at @object_path. The method handlers are represented by
+ * @iface_vtable. @instance_data contains additional caller specific data
+ * which is made available to handlers.
+ */
+struct sbus_interface *
+sbus_new_interface(TALLOC_CTX *mem_ctx,
+                   const char *object_path,
+                   struct sbus_vtable *iface_vtable,
+                   void *instance_data);
+
 /* Server Functions */
 int sbus_new_server(TALLOC_CTX *mem_ctx,
                     struct tevent_context *ev,
                     const char *address,
-                    struct sbus_interface *intf,
                     bool use_symlink,
                     struct sbus_connection **server,
                     sbus_server_conn_init_fn init_fn, void *init_pvt_data);
@@ -103,7 +118,6 @@ int sbus_new_server(TALLOC_CTX *mem_ctx,
 int sbus_new_connection(TALLOC_CTX *ctx,
                         struct tevent_context *ev,
                         const char *address,
-                        struct sbus_interface *intf,
                         struct sbus_connection **conn);
 
 /* sbus_add_connection
@@ -121,19 +135,11 @@ int sbus_new_connection(TALLOC_CTX *ctx,
 int sbus_init_connection(TALLOC_CTX *ctx,
                          struct tevent_context *ev,
                          DBusConnection *dbus_conn,
-                         struct sbus_interface *intf,
                          int connection_type,
                          struct sbus_connection **_conn);
 
-void sbus_conn_set_destructor(struct sbus_connection *conn,
-                              sbus_conn_destructor_fn destructor);
-
-int sbus_default_connection_destructor(void *ctx);
-
 DBusConnection *sbus_get_connection(struct sbus_connection *conn);
 void sbus_disconnect(struct sbus_connection *conn);
-void sbus_conn_set_private_data(struct sbus_connection *conn, void *pvt_data);
-void *sbus_conn_get_private_data(struct sbus_connection *conn);
 int sbus_conn_add_interface(struct sbus_connection *conn,
                             struct sbus_interface *intf);
 bool sbus_conn_disconnecting(struct sbus_connection *conn);