sd_bus_attach_event wrapper

[hadrianw]

Hello,

First I would like you thank you for this project.

I would like to ask if you have considered an sd_bus_attach_event wrapper? At my employer we use your nice project and we started to migrate also to sd-event for our event loops. For our needs I made a wrapper for it. It is not yet decided whether or not we will go with it.

I was wondering if you would consider accepting a pull request with it. Also if yes what would be required by you in terms of the implementation. For now I have a non-hermetic API for it: void IConnection::attachEventLoop(sd_event *ev, int priority). I understand it does not really fit with the rest of the library, but if there are ways you would see it better I'm all ears.

Kind regards and thank you,
Hadrian Węgrzynowski

[dleeds-cpi]

Personally, I think this addition would provide value and opportunities to optimize. On my current project, I have created a C++ wrapper around sd-event and a wrapper around IConnection that provides the event loop integration. This is rather convoluted, and it would be a much simpler option to attach directly to the underlying event loop.

To avoid introducing dependencies to the systemd/sd-event.h header in sdbus-c++, I would forward declare the sd_event struct, like this:

struct sd_event;
void IConnection::attachEventLoop(struct sd_event *e, int priority);

[sangelovic]

@hadrianw Thank you for kind words. Would you like to prepare a PR for this along the lines of @dleeds-cpi 's comment?

[hadrianw]

I will submit a pull request today or tomorrow.

[hadrianw]

Sorry for the delay. Here is my pull request. I didn't manage to add tests for it, as I had trouble setting up the environment for them to work.

#271