sid: Implement seeking

[mvtiaine]

there is no seek API in libsidplayfp, so use "brute force" seek

[mvtiaine]

ubuntu fails because reset() is only available since 2.15:
https://github.com/libsidplayfp/libsidplayfp/blob/libsidplayfp-2.15/src/sidplayfp/sidplayfp.h#L143C9-L143C19

I'll add version guard if/when #207 is merged

[radioactiveman]

How can I try this out? All SID sample files I found have no length and seeking is therefore not possible.

[mvtiaine]

The songlengths support is kind of hidden feature :P
https://github.com/audacious-media-player/audacious-plugins/blob/master/src/sid/xs_sidplay2.cc#L177

It expects Songlengths.md5 file from HVSC (https://www.hvsc.c64.org) in SIDDATADIR/sidplayfp (along kernal/basic/chargen files from libsidplayfp), which resolves to $prefix/share/sidplayfp usually, so for example /usr/local/share/sidplayfp/Songlengths.md5.

I have it symlinked to the HVSC dir:

$ ls -la /usr/local/share/sidplayfp/Songlengths.md5 
lrwxr-xr-x  1 root  wheel  49 Jan 17  2023 /usr/local/share/sidplayfp/Songlengths.md5 -> /Users/tundrah/C64Music/DOCUMENTS/Songlengths.md5

[mvtiaine]

Updated with requested changes

[radioactiveman]

Updated with requested changes

Thank you. 👍

@jlindgren90: Could you please review the changes as well?

Is the buffer usage correct? Should it be .clear() ed in play() like before with the delete[] call? Should a Plugin::cleanup() method be added?

[radioactiveman]

@jlindgren90: You probably missed my previous review comment. Could you check it please?

[jlindgren90]

I saw it but haven't had time to review, sorry.