Improve support for systemd-homed

[naritanara]

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This is somewhat crude but it seems to work. I have tested by running the get_user_data() method as root, but not by installing the modified greeter. Is there any predefined environment / guide for this kind of testing?

[naritanara]

updated to use the Dbus API

[jackpot51]

This should be optional, and cosmic-greeter should compile and run without that option enabled.

[nater1983]

I agree I maintain Slackware packages.

[jackpot51]

Will this cause cosmic-greeter to fail if home manager is not available?

[jackpot51]

Before approving it must be demonstrated that cosmic-greeter with this change can still run without systemd.

[naritanara]

Moved dependency to 'systemd' feature and properly handled errors. Tested the daemon with and without the 'systemd' feature, both compile and work as expected.

I left the systemd-homed cache paths for icons and backgrounds without feature-gating, please let me know if it would be better to feature-gate even if no dependencies are added.

[naritanara]

Additional testing: I have installed the new daemon on my system and verified that systemd-homed users appear on the greeter screen. Also tested the daemon without the 'systemd' feature, which works as before, without showing the homed users.

OS: Fedora COSMIC Atomic 44.20260519
Installation method: Enabled usroverlay and replaced the daemon, then stopped cosmic-greeter-daemon.service and restarted cosmic-greeter.service
Obtained result: With the systemd feature enabled, homed users show up. If user icons or wallpapers have been cached by systemd, they are used by the greeter as expected. Otherwise, the default values are used as before.

[jackpot51]

Thanks, that looks good to me. Just to make sure, I have asked for someone maintaining cosmic-greeter on a non-systemd distribution to test this.

[nater1983]

   Compiling clap_lex v1.1.0
warning: unused import: `tracing::warn`
 --> daemon/src/main.rs:8:5
  |
8 | use tracing::warn;
  |     ^^^^^^^^^^^^^
  |
  = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default

warning: unused import: `tracing::warn`
  --> src/greeter.rs:47:5
   |
47 | use tracing::warn;
   |     ^^^^^^^^^^^^^
   |
   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default

error[E0599]: `impl futures_util::Future<Output = UserFilter>` is not an iterator
  --> src/greeter.rs:86:40
   |
86 |             .filter(|user| user_filter.filter(user))
   |                                        ^^^^^^ `impl futures_util::Future<Output = UserFilter>` is not an iterator
   |
   = note: the following trait bounds were not satisfied:
           `impl futures_util::Future<Output = UserFilter>: Iterator`
           which is required by `&mut impl futures_util::Future<Output = UserFilter>: Iterator`
help: consider `await`ing on the `Future` and calling the method on its `Output`
   |
86 |             .filter(|user| user_filter.await.filter(user))
   |                                        ++++++

For more information about this error, try `rustc --explain E0599`.
warning: `cosmic-greeter` (lib) generated 1 warning
error: could not compile `cosmic-greeter` (lib) due to 1 previous error; 1 warning emitted
warning: build failed, waiting for other jobs to finish...
warning: `cosmic-greeter-daemon` (bin "cosmic-greeter-daemon") generated 1 warning (run `cargo fix --bin "cosmic-greeter-daemon" -p cosmic-greeter-daemon` to apply 1 suggestion)
error: recipe `build-debug` failed on line 47 with exit code 101

I compiled this on Slackware Current with rust-1.95. My Cosmic setup is up to date with version 1.0.13

[naritanara]

   Compiling clap_lex v1.1.0
warning: unused import: `tracing::warn`
 --> daemon/src/main.rs:8:5
  |
8 | use tracing::warn;
  |     ^^^^^^^^^^^^^
  |
  = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default

warning: unused import: `tracing::warn`
  --> src/greeter.rs:47:5
   |
47 | use tracing::warn;
   |     ^^^^^^^^^^^^^
   |
   = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default

error[E0599]: `impl futures_util::Future<Output = UserFilter>` is not an iterator
  --> src/greeter.rs:86:40
   |
86 |             .filter(|user| user_filter.filter(user))
   |                                        ^^^^^^ `impl futures_util::Future<Output = UserFilter>` is not an iterator
   |
   = note: the following trait bounds were not satisfied:
           `impl futures_util::Future<Output = UserFilter>: Iterator`
           which is required by `&mut impl futures_util::Future<Output = UserFilter>: Iterator`
help: consider `await`ing on the `Future` and calling the method on its `Output`
   |
86 |             .filter(|user| user_filter.await.filter(user))
   |                                        ++++++

For more information about this error, try `rustc --explain E0599`.
warning: `cosmic-greeter` (lib) generated 1 warning
error: could not compile `cosmic-greeter` (lib) due to 1 previous error; 1 warning emitted
warning: build failed, waiting for other jobs to finish...
warning: `cosmic-greeter-daemon` (bin "cosmic-greeter-daemon") generated 1 warning (run `cargo fix --bin "cosmic-greeter-daemon" -p cosmic-greeter-daemon` to apply 1 suggestion)
error: recipe `build-debug` failed on line 47 with exit code 101

I compiled this on Slackware Current with rust-1.95. My Cosmic setup is up to date with version 1.0.13

Oh, my bad, I did not realize that the greeter directly links with the daemon library (I was directly compiling the daemon, not the whole workspace). I will push a fix shortly.

[naritanara]

Hey @nater1983 could you check again with my latest commit? :)

[nater1983]

Hey @nater1983 could you check again with my latest commit? :)

Work's perfectly. Thank you so much.