This makes D-Bus proxy signal registration more flexible, more dynamic, and less error-prone since no `finishRegistration()` call is needed. A proxy can register to a signal at any time during its lifetime, and can unregister freely by simply destroying the associated slot.
This improves the D-Bus object API registration/unregistration by making it more flexible, more dynamic, closer to sd-bus API design but still on high abstraction level, and -- most importantly -- less error-prone since no `finishRegistration()` call is needed anymore.
This makes the library more robust and prone to user's errors when the user writes an extension for their custom type. In case they forget to implement a serialization function for that type and yet insert an object of that type into sdbus::Message, the current behavior is that, surprisingly, the library masks the error as it resolves the call to the Variant overload, because Variant provides an implicit template converting constructor, so the library tries to construct first the Variant object from the object of custom type, and then inserting into the message that Variant object. Variant constructor serializes the underlying object into its internal message object, which resolves to the same message insertion overload, creating an infinite recursion and ultimately the stack overflow. This is undesired and plain wrong. Marking this Variant converting constructor solves these problems, plus in overall it makes the code a little safer and more verbose. With explicit Variant constructor, when the user forgets to implement a serialization function for their type, the call of such function will fail with an expressive compilation error, and will produce no undesired, surprising results.
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.
This also introduces `always_false` technique instead of `sizeof` trick for unsupported D-Bus type representation static assert. This one is more expressive and leads to more specific, more revealing compiler error messages.
* chore: Use std::exchange in UnixFd
This was suggested in code review for #376 .
* fix: Protect against UnixFd self-assignment
While self-assignment is rare, it is expected to be safe. Add a check
to prevent putting the object in an invalid state.
* fix: Improve hygiene around dup system call
- Don't try to call dup on a negative value.
- Check dup return code and throw if it fails, rather than returning an
empty UnixFd object.
* chore: Move UnixFd::close to Types.cpp
Minor convenience for applications: unistd.h doesn't have to be included
in the public header.
---------
Co-authored-by: David Reiss <dreiss@meta.com>
* Catch and process all exceptions (not just sdbus::Error) from callback handlers
* Unify handling of exceptions from all types of callbacks -- always set sd_bus_error and return a negative result number in case of exception
Although libsystemd logs (with DEBUG severity) all errors from such callback handlers (except method callback handler), it seems to be out of our control. One of handy sdbus-c++ features could be the ability for clients to install a log callback, which sdbus-c++ would call in case of exceptions flying from callback handlers. In case something doesn't work for clients (especially novices), they can first look into these logs.
This may be handy in common situations like ignored signals on client side because of the inadvertent mismatch between real signal signature and signal handler signature. Like here: #373. (Although in this specific case of signals, there is a solution with an additional const sdbus::Error* argument that would reveal such an error.)
* 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>
* feat: add async property get/set convenience support classes
* feat: add no-reply and async overloads to Properties_proxy
* feat: add convenience functions for GetAll functionality
* test: add tests for new functionality
* add codegen IDL support and documentation
* feat: support serialization of array, span and unordered_map
* fix some spelling mistakes
* docs: update table of valid c++ types
---------
Co-authored-by: Marcel Hellwig <github@cookiesoft.de>
* Add methods to initiate custom session bus connection
The new function helper `createSessionBusConnectionWithAddress` allows to create connection to session bus with custom address.
Signed-off-by: Alexander Livenets <a.livenets@gmail.com>
* feat: add support for session bus connection at custom address
Co-authored-by: Stanislav Angelovic <stanislav.angelovic@siemens.com>
* Since ObjectPath and Signature have a user-declared copy-ctor and copy
assignment operator the implicit declaration of corresponding move
operations is disabled. Explicitly add defaulted versions so that
move operations actually move instead of copy.
* See: https://github.com/Kistler-Group/sdbus-cpp/issues/230
fix timeout handling
* Despite what is documented in sd_bus_get_timeout(3), the timeout
returned is actually an absolute time point of Linux's CLOCK_MONOTONIC
clock. Hence, we first have to subtract the current time from the
timeout in order to get a relative time that can be passed to poll.
* For async call timeouts to reliably work, we need a way to notify the
event loop of a connection that is currently blocked waiting in poll.
I.e. assume the event loop thread entered poll with a timeout set to
T1. Afterwards, the main thread starts an async call C with a timeout
T2 < T1. In order for C to be canceled after its timeout T1 has
elapsed, we have to be able to notify the event loop so that it can
update its poll data.
Co-authored-by: Urs Ritzmann <ursritzmann@protonmail.ch>
Co-authored-by: Lukasz Marcul <lukasz.marcul@onemeter.com>
