Ddlm crashes

[eternal-sorrow]

What I get is the screen is flickering as systemd restarts greetd several times. It shows ddlm for a split second and then it shows the VT cursor in the corner of the screen. In the end systemd gives up and I get stuck t the screen that shows DDLM but I cannot interact with it. Furthermore I can't even switch to another TTY. Even after pressing Alt+SysRQ+R. So the only thing that's left for me is to reboot via Alt+SysRQ+REISUB.

After I rebooted and disabled greetd startup with recovery mode, I was able to see the journal, but there was nothing except this error from greetd:

error: check_children: greeter exited without creating a session

[deathowl]

I'll check this out as soon as I can, thanks for the report

[deathowl]

I checked with the latest build , also with the one from AUR just to be sure. And it works for me. :( Can you make sure greetd(or greeter) user is part of video group? Also could you please attempt running it with RUST_BACKTRACE=1 and capturing the stdout. It would help greatly in debugging

[eternal-sorrow]

Not soon. Because after I start it, it locks me out of console and I'm unable to do anything except reboot with SysRq.

[eternal-sorrow]

greetd is indeed in the video group. Otherwise it wouldn't work for me before the update. The problem started after #7 this was merged.

[deathowl]

maybe try journalctl -u greetd?

[eternal-sorrow]

That's exactly what I did. There was no errors from DDLM. Just an error from greetd:

error: check_children: greeter exited without creating a session

[deathowl]

or make command="exec systemd-cat --identifier=ddlm -- RUST_BACKTRACE=1 ddlm"
then after crashing you can journalctl -t ddlm

[eternal-sorrow]

I'll try.

[deathowl]

sorry.
command = "systemd-cat --identifier=ddlm -- ddlm"

[eternal-sorrow]

I have command = "ddlm --target=/etc/greetd/run_sway.sh" now.

[deathowl]

That might be it. the pr where i backported the session selection + cleanup deprecated the targets flag.
now it consumes ["/usr/share/wayland-sessions", "/usr/share/xsessions"] to select available sessions

[eternal-sorrow]

Well, that's too bad. Will it at least preselect a session that was used last time? Also, I use a wrapper script to start sway to export the environment variables. Do I need to create a custom session .desktop file for that?

[eternal-sorrow]

Even better is I could pass a session from command line and don't need to select one during login.

[deathowl]

I can readd the flag . And no, last selected session is not saved yet, but will do it once I have time, I'll attempt to do that over the weekend, alongside with the user listing and selection

[eternal-sorrow]

If it would either remember the selected session end user or take the default values for session and user from command line, that would be perfect for me. Either way is good.

If you re-add the flag to pass a custom script, then session selection should be disabled when this flag is passed.

[eternal-sorrow]

Ideally I would like to only enter the password to login.

[deathowl]

I'll work on saving the last used username and session over the weekend.

[eternal-sorrow]

I tried that trick with systemd-cat and got this error message from ddlm:

thread 'main' panicked at 'unable to enter raw mode: Os { code: 25, kind: Uncategorized, message: "Inappropriate ioctl for device" }', src/main.rs:431:10

[deathowl]

there was no changes there since the initial release.

[deathowl]

could you ls /usr/share/wayland-sessions and ls /usr/share/xsessions? Because i have a feeling there is something interesting about your installation.

[eternal-sorrow]

> ls /usr/share/wayland-sessions
sway.desktop
> ls /usr/share/xsessions
ls: cannot access '/usr/share/xsessions': No such file or directory

[hlbstd]

I tried that trick with systemd-cat and got this error message from ddlm:

thread 'main' panicked at 'unable to enter raw mode: Os { code: 25, kind: Uncategorized, message: "Inappropriate ioctl for device" }', src/main.rs:431:10

This message is a consequence of trying to capture the program output with systemd-cat, it hides the actual issue.

[eternal-sorrow]

So? Is there a way to capture the error output of ddlm without breaking it?

[jfoy]

I see this same failure. As a diagnostic, I commented out the let raw = portions of main.rs and was able to generate the following error from ddlm via greetd.

thread 'main' panicked at 'index out of bounds: the len is 1 but the index is 1', src/main.rs:212:14

@deathowl At a guess, this may not repro for you because you have more than one session file in /usr/share/wayland-sessions (or /usr/share/xsessions)? To test this idea, I added a dummy second file to /usr/share/wayland-sessions and suddenly ddlm stopped crashing at startup.

@eternal-sorrow That may give you a usable workaround.

[deathowl]

Thank you! Now this is something that I can look into fixing

[eternal-sorrow]

Shouldn't Rust prevent this kind of crashes by design?

[deathowl]

the contents of the file with xsessions and wlsessions of your machine are not known on compile time, so i doubt Rust provides any extra safety here

[rytec-nl]

I ran into the same issue because the session folders are not present on my NixOs machine. I reinstated the --target flag in my fork here. I made is so that it works next to the session files (I cannot test that as I don't have those myself). If you want I will create a pull request, I would need to clean it up a bit as I added some NixOS files (a flake for devenv).

Let me know!