Fix building and running on systems without systemd

[Foxinatel]

Addresses: #51

Currently trying to build without the systemd feature causes compile time errors. The first commit in this PR simply fixes those.

The seconds commit turns tracing-journald into an optional dependency which is only included when building with the systemd feature.

The third commit removes the runtime panic that occurs when journald is not available on a system, falling back to a default and providing a warning instead of a hard crash. This is useful on distros like Artix or Devuan where many features of systemd are available (dbus, logind), such that building with the systemd feature is preferable, but journald is not present.

[ids1024]

I suppose if journald isn't present, we should probably try logging to syslog? That isn't a blocker for this though. Whatever we do it should be consistent with cosmic-comp, etc.

I'm interested to see what other parts of Cosmic may have issues without systemd. I know cosmic-comp works on Gentoo OpenRC and (at least when I last tried it) FreeBSD, but I haven't tried running all the Cosmic components on either.

[Foxinatel]

Just noticed that the cfg directive applies to the entire if-let-else block in the third commit and therefore no logging will happen at all if building without the systemd feature. I'll update the commit for that tomorrow.

[Calandracas606]

working on packaging this void linux, which also lacks systemd
void-linux/void-packages#51735

no build errors, but failing at runtime when launching cosmic-session

Error: 
   0: failed to connect to journald
   1: No such file or directory (os error 2)

Location:
   src/main.rs:46

[fulalas]

@Calandracas606, I believe you should remove the last 2 lines in Cargo.toml:

systemd = ["dep:zbus_systemd", "dep:tracing-journald"]
default = ["systemd"]

Still, it fails to run due to some no such file or directory:

Not sure what's going on tbh.

[Foxinatel]

I believe you should remove the last 2 lines in Cargo.toml

It would be a better idea to just pass the --no-default-features flag to cargo build to exclude the systemd feature

Still, it fails to run due to some no such file or directory:
Not sure what's going on tbh.

I can't reproduce this on my own system (Artix) with these patches applied. If you're able to get a backtrace with debugging info then I'd be happy to take a look.

[fulalas]

@Foxinatel, do you mind explaining the step by step to achieve that? Thanks!

[fulalas]

EDIT: Ignore below. We need to call start-cosmic and not cosmic-session. All good now! Thanks :)

Not sure if this helps (COLORBT_SHOW_HIDDEN=1 RUST_BACKTRACE=full cosmic-session):

�[2m2024-08-10T20:50:02.094445Z�[0m �[31mERROR�[0m �[2mpanic�[0m�[2m:�[0m thread 'main' panicked at 'called `Result::unwrap()` on an `Err` value: Os { code: 13, kind: PermissionDenied, message: "Permission denied" }': /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/color-eyre-0.6.2/src/config.rs:284
   0: <backtrace::capture::Backtrace as core::default::Default>::default
             at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/backtrace-0.3.68/src/capture.rs:410:9
   1: log_panics::Config::install_panic_hook::{{closure}}
             at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/log-panics-2.1.0/src/lib.rs:115:29
   2: <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/alloc/src/boxed.rs:2164:9
      std::panicking::rust_panic_with_hook
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/std/src/panicking.rs:805:13
   3: std::panicking::begin_panic_handler::{{closure}}
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/std/src/panicking.rs:671:13
   4: std::sys::backtrace::__rust_end_short_backtrace
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/std/src/sys/backtrace.rs:170:18
   5: rust_begin_unwind
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/std/src/panicking.rs:662:5
   6: core::panicking::panic_fmt
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/core/src/panicking.rs:74:14
   7: core::result::unwrap_failed
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/core/src/result.rs:1679:5
   8: core::result::Result<T,E>::unwrap
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/core/src/result.rs:1102:23
      <color_eyre::config::SourceSection as core::fmt::Display>::fmt
             at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/color-eyre-0.6.2/src/config.rs:284:27
   9: core::fmt::rt::Argument::fmt
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/core/src/fmt/rt.rs:173:76
      core::fmt::write
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/core/src/fmt/mod.rs:1178:21
  10: <&mut W as core::fmt::Write::write_fmt::SpecWriteFmt>::spec_write_fmt
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/core/src/fmt/mod.rs:226:21
  11: core::fmt::Write::write_fmt
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/core/src/fmt/mod.rs:231:9
  12: <color_eyre::config::StyledFrame as core::fmt::Display>::fmt
             at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/color-eyre-0.6.2/src/config.rs:262:13
  13: core::fmt::rt::Argument::fmt
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/core/src/fmt/rt.rs:173:76
      core::fmt::write
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/core/src/fmt/mod.rs:1178:21
  14: <&mut W as core::fmt::Write::write_fmt::SpecWriteFmt>::spec_write_fmt
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/core/src/fmt/mod.rs:226:21
  15: core::fmt::Write::write_fmt
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/core/src/fmt/mod.rs:231:9
  16: <color_eyre::config::BacktraceFormatter as core::fmt::Display>::fmt
             at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/color-eyre-0.6.2/src/config.rs:1171:13
  17: core::fmt::rt::Argument::fmt
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/core/src/fmt/rt.rs:173:76
      core::fmt::write
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/core/src/fmt/mod.rs:1178:21
  18: <&mut W as core::fmt::Write::write_fmt::SpecWriteFmt>::spec_write_fmt
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/core/src/fmt/mod.rs:226:21
  19: core::fmt::Write::write_fmt
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/core/src/fmt/mod.rs:231:9
  20: color_eyre::handler::<impl eyre::EyreHandler for color_eyre::Handler>::debug
             at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/color-eyre-0.6.2/src/handler.rs:119:13
  21: eyre::fmt::<impl eyre::error::ErrorImpl<()>>::debug::{{closure}}
             at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/eyre-0.6.8/src/fmt.rs:15:28
  22: core::option::Option<T>::map
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/core/src/option.rs:1107:29
  23: eyre::fmt::<impl eyre::error::ErrorImpl<()>>::debug
             at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/eyre-0.6.8/src/fmt.rs:13:9
  24: eyre::error::<impl core::fmt::Debug for eyre::Report>::fmt
             at /root/.cargo/registry/src/index.crates.io-6f17d22bba15001f/eyre-0.6.8/src/error.rs:490:9
  25: core::fmt::rt::Argument::fmt
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/core/src/fmt/rt.rs:173:76
      core::fmt::write
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/core/src/fmt/mod.rs:1178:21
  26: std::io::Write::write_fmt
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/std/src/io/mod.rs:1823:15
      <&std::io::stdio::Stderr as std::io::Write>::write_fmt
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/std/src/io/stdio.rs:1018:9
  27: <std::io::stdio::Stderr as std::io::Write>::write_fmt
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/std/src/io/stdio.rs:992:9
      std::io::stdio::attempt_print_to_stderr
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/std/src/io/stdio.rs:1144:13
  28: <core::result::Result<T,E> as std::process::Termination>::report
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/std/src/process.rs:2470:17
  29: std::rt::lang_start::{{closure}}
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/std/src/rt.rs:164:18
  30: core::ops::function::impls::<impl core::ops::function::FnOnce<A> for &F>::call_once
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/core/src/ops/function.rs:284:13
      std::panicking::try::do_call
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/std/src/panicking.rs:554:40
      std::panicking::try
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/std/src/panicking.rs:518:19
      std::panic::catch_unwind
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/std/src/panic.rs:345:14
      std::rt::lang_start_internal::{{closure}}
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/std/src/rt.rs:143:48
      std::panicking::try::do_call
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/std/src/panicking.rs:554:40
      std::panicking::try
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/std/src/panicking.rs:518:19
      std::panic::catch_unwind
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/std/src/panic.rs:345:14
      std::rt::lang_start_internal
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/std/src/rt.rs:143:20
  31: std::rt::lang_start
             at /rustc/ca5d25e2c41f5a6b4ce65c681bf2f94c7ead1f14/library/std/src/rt.rs:163:17
  32: main
  33: __libc_start_call_main
  34: __libc_start_main@GLIBC_2.2.5
  35: _start
             at /tmp/glibc-2.40/csu/../sysdeps/x86_64/start.S:115

Why is it looking for /root/.cargo when in the testing machine there's no such thing?

[Foxinatel]

Glad you managed to figure it out :)

[Quackdoc]

I can confirm at least that on artix that this + the PR for cosmic-notifications allows cosmic de to work, so it would be nice if these can be reviewed

[Drakulix]

LGTM. Thanks for working on this!