forked from Kistler-Group/sdbus-cpp
107c6a1a97
This reorganizes the layers of abstraction in the sense how `Message` depends on `Connection` and vice versa. Now, `Message` has a link to the `Connection`. This replaces the shortcut link to the low-level `SdBus` interface that the `Message` kept. The interactions from `Message` now go through `Connection` which forwards them to `SdBus`. `Connection` is now a sole owner of the low-level `SdBus` interface. This allows for future changes around `SdBus` (e.g. a change from virtual functions back to non-virtual functions) without affecting the rest of the library. `Proxy`s and `Object`s can now send messages directly without having to go through `Connection`. The `Connection` no more depends on `Message` business-logic methods; it serves only as a factory for messages. The flow for creating messages: `Proxy`/`Object` -> `Connection` -> `SdBus` The flow for sending messages: (`Proxy`/`Object` ->) `Message` -> `Connection` -> `SdBus` This also better reflects how dependencies are managed in the underlying sd-bus library. Additionally, `getSdBusInterface()` methods are removed which was anyway planned, and improves the design by "Tell, don't ask" principle. This refactoring is the necessary enabler for other upcoming improvements (regarding sending long messages, or creds refactoring, for example).