feat(control char): add basic control char support

[cmsxbc]

Try to fix #138

Description

• A basic solution for control chars render (\n, \r, \b, \t)

reproduce

# any mono font is good.
./i3lock -t -e -f -n --no-verify \
    --greeter-pos=1200:500 \
    --greeter-font="Cascadia Code" \
    --greeter-text="A example
$(printf 'newline\nnewline')
$(printf 'carriage\rreturn')
$(printf 'newline\r\nreturn')
$(printf 'tab\ttab')
$(printf 'backspace\bbackspace')
$(printf '\rdef    def')
$(printf 'tabtab\ttab')
$(printf 'tabtabtab\ttab')"

Screenshots/screencaps

before fix.

after fix.

Release notes

Notes: Support basic control chars.(\n \r \b \t)

[Raymo111]

This looks great. Can you add \t support as well, or would that be too difficult?

[cmsxbc]

This looks great. Can you add \t support as well, or would that be too difficult?

Yep, I will have a try, but i don't know the exactly behavior of \t yet, especially when the font is not monospace.
Or maybe I could just replace \t with 2 spaces (or 4, 8 or any other user configured) ?

[Raymo111]

Actually you know what, I don't think tab is very useful or necessary. People can just just multiple spaces.

[cmsxbc]

Actually you know what, I don't think tab is very useful or necessary. People can just just multiple spaces.

So do I. I just have implemented a \t with same behavior as printf in c

[Raymo111]

I like that this works without printf as well (just put the characters in a script). Nice job. Can you document your changes in the manpage (and bump the manpage date to Sep 2021) please?

[Raymo111]

More importantly, bug: when there's a tab character immediately after a newline the 2nd line goes all the way to the left of the screen:

[cmsxbc]

Done, and I'm not good at English, please fix me if there is any unreadable thing.

[Raymo111]

LGTM

[ShadiZade]

Hey, This just doesn't work for me. I even used your exact same example code, and the problem in your first image still shows up. Here's my code:

numofdays=$(date +"%j")
numofweeks=$(echo "scale=1; $numofdays/7" | bc )
i3lock -kef -c aa2200ff --radius 150 --ring-width 5.0 --ring-color=000000ff \
	 --ringver-color=000000ff --insidever-color=00000000 --ringwrong-color=000000ff \
	 --insidewrong-color=00000000 --keyhl-color=ffffffff --bshl-color=aa2200ff \
	 --date-font="Inconsolata Semi Condensed SemiBold" --verif-font="Inconsolata Extra Condensed ExtraBold" \
	 --time-font="Inconsolata Extra Condensed ExtraBold" --layout-font="Inconsolata Extra Condensed ExtraBold" \
	 --wrong-font="Inconsolata Extra Condensed ExtraBold" --wrong-text="INCORRECT" --verif-text="UNLOCKING" \
	 --noinput-text="" --verif-size=22 --wrong-size=22 --time-size=75 --date-size=18 \
	 --date-str="%a, %e %b %Y ("$numofweeks" weeks)" \
	 --greeter-text="A example
	 $(printf 'newline\nnewline')
	 $(printf 'carriage\rreturn')
	 $(printf 'newline\r\nreturn')
	 $(printf 'tab\ttab')
	 $(printf 'backspace\bbackspace')
	 $(printf '\rdef    def')
	 $(printf 'tabtab\ttab')
	 $(printf 'tabtabtab\ttab')" \
	 --no-verify

Here's the info
i3lock: version 2.13.c.4
zsh 5.9 (x86_64-pc-linux-gnu
Kernel: 5.18.12-3-MANJARO
awesome v4.3

[Raymo111]

@ShadiZade try with Bash? (it works for me)
Check your bash version as well.

[ShadiZade]

@Raymo111 Nope, doesn't work with bash either.
GNU bash, version 5.1.16(1)-release (x86_64-pc-linux-gnu)

[Raymo111]

I'm on the same version of bash. What happens when you run it as a script after adding #!/bin/bash to the top?

[ShadiZade]

same thing.

[Raymo111]

Sorry, not sure then. I copy-pasted your code into a blank bash script and it worked...

[cmsxbc]

@ShadiZade I think this fix is not included in 2.13.c.4 which released at June 5, 2021. And this fix merged into master at Jan 11, 2022.

[ShadiZade]

@cmsxbc how come the AUR package is so far behind?

P.S. I tried installing i3lock-color-git from the AUR, and it threw me a bunch of errors about the --no-verify flag. the \n worked though.

[ShadiZade]

@Raymo111 I went ahead and built the package manually. It worked (looks like @cmsxbc was right), but only in the greeter text. Was it never meant to work in the date string?

[Raymo111]

@ShadiZade I'm using i3lock-color-git from the AUR and everything works, no errors with the no-verify flag. I haven't created a new release in a year now hence the discrepancy between the packages/releases and self-built ones, I'll spin up a new release next week.

[ShadiZade]

Very well, thanks for your efforts. One last question: is the linebreak supposed to work in the date string, or only in the greeter text?

[Raymo111]

It's supposed to work everywhere.