fix: prevent fork loop and JSON hang in keybinds hint

[snakeice]

Problem

Two bugs in the keybinds hint system were causing system-wide performance degradation (fork storms with ~568 forks/s, load average spikes to 100+).

Bug 1: keybinds_hint.sh — infinite self-re-execution (exec $0)

The script uses exec $0 in two places as a fallback when rofi produces no output or when a dispatch fails. This causes the script to re-execute itself indefinitely, spawning hundreds of python3 processes per second.

Before:

RUN() {
    case ... in *"Not enough arguments"*) exec $0 ;; esac
}
...
else
    exec $0
fi

Fix: Replace exec $0 with exit 0. If the script reaches a dead end, it should exit, not loop.

Bug 2: hint-hyprland.py — infinite retry on broken JSON

get_hyprctl_binds() had a while True loop that retried hyprctl binds -j forever when JSON parsing failed. On Hyprland 0.56.0, hyprctl binds -j returns malformed JSON (fields shifted, non-numeric values in numeric fields), causing the script to hang indefinitely in the retry loop.

$ hyprctl binds -j | python3 -m json.tool
# JSONDecodeError: Expecting value: line 15 column 16 (char 303)

Fix:

• Try JSON first with a 5s timeout
• If JSON is invalid, fall back to parsing the text output of hyprctl binds (no -j flag)
• All subprocess calls have timeout=5 to prevent indefinite hangs

Impact

• Fork rate dropped from ~568/s to ~7/s
• System load returned to normal (was spiking to 100+ on a 14-thread CPU)
• Keybinds hint (Super+/) now works on Hyprland 0.56.0 where hyprctl binds -j is broken

Testing

Tested on:

• Hyprland 0.56.0 (commit 36b2e0c)
• Kernel 7.1.4-1-cachyos
• Python 3.11

# Before: hangs forever
$ python3 hint-hyprland.py --format rofi
# (no output, CPU spins)

# After: works correctly
$ python3 hint-hyprland.py --format rofi | head -3
 Window Management  ::: ::: Window Management
SUPER + Q > close focused window ::: exec ::: hyde-shell dontkillsteam
ALT + F4 > close focused window ::: exec ::: hyde-shell dontkillsteam

Summary by CodeRabbit

• Bug Fixes
  • Improved keybinding detection by falling back to text-based parsing when structured output isn’t available.
  • Added bounded command execution for keybind retrieval to avoid indefinite waiting.
  • Prevented the keybind dispatch script from repeatedly restarting when dispatch arguments are missing or selection can’t be performed.
  • Enhanced normalization of keybinding details, including modifier, repeat, lock, mouse, release, and description handling.

[coderabbitai]

Note

GitHub couldn't provide a complete incremental comparison for this pull request, so CodeRabbit is performing a full review instead. This review may take a little longer.