BOSS data being incorrectly overwritten at each boot

[jonbarrow]

Current Behavior

Every time Splatoon launches, the games BOSS data is overwritten. This likely affects all games

Expected Behavior

BOSS data should not be overwritten unless the data ID has changed

Steps to Reproduce

• Launch Splatoon
• Close Cemu
• Modify downloaded BOSS data
• Launch Splatoon again
• Modified BOSS data is overwritten

System Info (Optional)

No response

Emulation Settings (Optional)

No response

Logs (Optional)

No response

[jonbarrow]

I'm making this report on behalf of a few users who reported it to us, but didn't seem to report it to you

This issue only started happening after our recent BOSS server updates at Pretendo, so something we did definitely had a hand here, however this issue cannot be replicated on real hardware so it seems to actually be a Cemu issue? Relevant issue on our side here PretendoNetwork/BOSS#37

I have not done a huge deep dive into Cemu's BOSS implementation, but I think the issue is related to these lines, which seems to redownload the data if the file exists but has been modified on the server?

This seems sensible, but it seems to not be how real hardware works. In our experience, if a data ID exists already then the console doesn't try to redownload the content at all (as seen in network dumps). We've also experienced this first hand in Splatoon, where we've changed the map rotations in BOSS but forgot to bump the data ID and users couldn't connect due to having outdated rotations

I think just removing the part that redownloads the content should be enough to fix this?

[Exzap]

This is mostly a symptom of an incomplete (and not very good) implementation for BOSS on our side. The good news is that there is a full rewrite of the BOSS code planned for Cemu 2.7 and it's almost finished. Off the top of my head I don't know if it solves the reported issue but I am sure it will be handled by the time it gets merged. Thanks for reporting this.

Will close this once the fixed code has been merged and confirmed to work