Improve usage message printing

[yshui]

No description provided.

[codecov]

Codecov Report

Merging #877 (59de702) into next (2dae094) will decrease coverage by 0.32%.
The diff coverage is 12.82%.

@@            Coverage Diff             @@
##             next     #877      +/-   ##
==========================================
- Coverage   37.97%   37.64%   -0.33%     
==========================================
  Files          48       48              
  Lines       10567    10641      +74     
==========================================
- Hits         4013     4006       -7     
- Misses       6554     6635      +81     

Impacted Files	Coverage Δ
src/dbus.c	21.71% <0.00%> (ø)
src/picom.c	66.95% <ø> (-0.62%)	⬇️
src/options.c	19.71% <11.84%> (-1.64%)	⬇️
src/diagnostic.c	75.00% <100.00%> (ø)
src/win.c	67.47% <0.00%> (-0.82%)	⬇️

[tryone144]

Thanks for simplifying the options interface! This has been bugging me for a while. 😅

---

I have some experimental code locally that uses an enum for the option id's / shortcodes instead of relying on the magic numbers. Having that would be a nice addition when extending/restructuring the options.

However, I am still struggling to find a nice way of merging the general handling in options.c and config_libconfig.c. Having the same logic in two places is kind of not nice. The first attempt using macros has turned out to be even messier...

[yshui]

@tryone144 can i see your first attempt?

[tryone144]

@tryone144 can i see your first attempt?

I am currently away from my main machine on a spotty (at best) internet connection. I will push the partially working WIP code as soon as I get back.
Code-reviews might be delayed as well. Unless you are in a hurry to merge the latest PRs, I recon I'd get these done around the next weekend.

[tryone144]

@tryone144 can i see your first attempt?

See this branch. This is out-of-date with next and might not compile.
Notable changes are:

• enum over all configuration options in options_defs.h to get rid of manually assigned ids.
• do all range-checking and clamping in options.c and only there.
• preprocessor macros for handling int, long, double, bool, and string arguments in options_macros.h. The idea was to define appropriate macros for getopt and libconfig and then include this header as the single source of truth (I think the approach is called X Macros). Ended up being quite messy in the current state and not really a step forward; particularly due to the edge cases and special handling some options require.

[yshui]

@tryone144 I've looked at your attempt. Nice idea but it did end up being quite messy. I think we can merge this PR as an incremental improvement. Eventually I think it might be a good idea to generate the config code from a python script or something.