Until now, the solution to ensure that even large messages are fully sent out has been to flush the connection queues after each sending of a message, which is likely an unnecessary call (with unnecessary cost) in vast majority of cases, and which may block the connection from doing other work until the large message is fully sent out. This was a rather quick, hacky workaround.
Now, after the sending the message we check whether it has been sent out fully or not. If not (outbound queues are non-empty), then we send a wake-up signal to the connection event loop. The event loop thread then fetches new sd-bus timeouts and events and will see that there are pending outbound messages to process, and will process them together with any other prospective pending events, until there is nothing to process (i.e., the outbound message has been fully dispatched).
Make all the API consistent by using return_slot_t-based overloads for returning the slots to clients, and overloads without that tag for "floating" slots. floating_slot_t tag was previously added for API backwards compatibility reasons, but now is a (counter-)duplicate to the return_slot_t.
Moving adaptor or proxy instances changes their `this` pointer. But `this` is captured by value in closures used by those instances, and this remains unchanged on move, leading to accessing an invalid instance when a lambda expression executes. Supporting move semantics would require unsubscribing/unregistering vtable, handlers, etc. and re-subscribing and re-registering all that, which is too complicated and may have side effects. Hence it has been decided that these classes are not moveable. One may use an indirection with e.g. `std::unique_ptr` to get move semantics.
This introduces strong types for `std::string`-based D-Bus types. This facilitates safer, less error-prone and more expressive API.
What previously was `auto proxy = createProxy("org.sdbuscpp.concatenator", "/org/sdbuscpp/concatenator");` is now written like `auto proxy = createProxy(ServiceName{"org.sdbuscpp.concatenator"}, ObjectPath{"/org/sdbuscpp/concatenator"});`.
These types are:
* `ObjectPath` type for the object path (the type has been around already but now is also used consistently in sdbus-c++ API for object path strings),
* `InterfaceName` type for D-Bus interface names,
* `BusName` (and its aliases `ServiceName` and `ConnectionName`) type for bus/service/connection names,
* `MemberName` (and its aliases `MethodName`, `SignalName` and `PropertyName`) type for D-Bus method, signal and property names,
* `Signature` type for the D-Bus signature (the type has been around already but now is also used consistently in sdbus-c++ API for signature strings),
* `Error::Name` type for D-Bus error names.
This PR makes things around connection factories a little more consistent and more intuitive:
* createConnection() has been removed. One shall call more expressive createSystemConnection() instead to get a connection to the system bus.
* createDefaultBusConnection() has been renamed to createBusConnection(), so as not to be confused with libsystemd's default_bus, which is a different thing (a reusable thread-local bus).
Proxies still by default call createBusConnection() to get a connection when the connection is not provided explicitly by the caller, but now createBusConnection() does a different thing, so now the proxies connect to either session bus or system bus depending on the context (as opposed to always to system bus like before).
The integration tests were modified to use createBusConnection().
Signatures of callbacks async_reply_handler, signal_handler, message_handler and property_set_callback were modified to take input message objects by value, as opposed to non-const ref.
The callee assumes ownership of the message. This API is more idiomatic, more expressive, cleaner and safer. Move semantics is used to pass messages to the callback handlers. In some cases, this also improves performance.
* feat: add support for direct connections
* refactor: simplify a bit, change comments, extend tests
* fix: compiler warning about unused variable
* docs: add section on direct connections to the tutorial
---------
Co-authored-by: Maksim Fedyarov <m.fedyarov@omp.ru>
Co-authored-by: Stanislav Angelovič <stanislav.angelovic@protonmail.com>
Even though they have the same value, they are something fundamentally different.
Therefore it is extremely confusing if the constant INTERFACE_NAME is passed
where actually a well-known BUS_NAME (destination) should go.
* fix: minor documentation and test improvements
* doc: add link to tests in standard interfaces tutorial secion
* Update README.md
Co-authored-by: Urs Ritzmann <urs.ritzmann@kistler.com>
* Update docs/using-sdbus-c++.md
Co-authored-by: Urs Ritzmann <urs.ritzmann@kistler.com>
* Use cmake instead of make in build instructions
Co-authored-by: Stanislav Angelovic <stanislav.angelovic@siemens.com>
Co-authored-by: Urs Ritzmann <urs.ritzmann@kistler.com>
