corrupted saved game: "string ended unexpectedly"

[king of nowhere]

I got an error message when trying to open a saved game:

"economies: player 7: Stream ended unexpectedly (0 bytes read, 4 expected)"

and the save cannot be opened. the closer autosave is fine, luckily.

file attached.

[SirVer (sirver)]

I can confirm that the game does not load on my system either.

I unzipped the save and looked at the data sizes in the save file and they seem to be reasonable. I did not analyze the contents of the economy file yet, but I do not understand how the file could become faulty.

Could you attach the savegame that is close by too? I'd like to compare the file size and maybe I can trigger an invalid save with it somehow.

stdout: https://gist.github.com/SirVer/30b1cf558e489f3d539359da79c676ad
sizes: https://gist.github.com/SirVer/6c6bf7bf7a81e39a7c05fd86d48d74fe

[king of nowhere (lainluigi86)]

that's the closer autosave, some 20 minutes before the faulty one. Restarting from the autosave, i kept playing for another couple hours and the saved games I made further worked correctly

[SirVer (sirver)]

I investigated the two saves and can conclude that the problem is the following:

When the problematic game was saved, player 1 had 34 economies - at least 34 economies of player one seem to be saved into the file. When the game is loaded, the Player class owns 35 economies. The code happily loaded as the 35th economy the first economy of player 2 that was saved. In the end, the loader ran out of economies for player 7.

As of now I do not know why there have been more economies on load then on save. I suggested the attached branch for merge. It detects if there are a different amount of economies on save or load and crashes on load, maybe giving us an opportunity to catch this earlier.

king: I think your particular game is a strong test case because of many ships and many economies. Could you continue playing it once this is merged and update this bug with crashing savegames?

[king of nowhere (lainluigi86)]

"Could you continue playing it once this is merged and update this bug with crashing savegames?"

that one is a challenge map I've been working on and off for over a year trying to find a right balance. So yes, I will keep playing it.

[Launchpad Janitor (janitor)]

[Expired for widelands because there has been no activity for 60 days.]

[GunChleoc (gunchleoc)]

Also reported in https://bugs.launchpad.net/widelands/+bug/1735954 with an attached savegame

[Manfred (manphi)]

Is there any solution for the corrupted savegames? I've been playing for several hours on a huge map and got this error on a savegame. I first ignored it because I thought maybe it will not effect any future saves, but it did. And now i would have to play about 8 hours since my last uncurrupted savegame.

[GunChleoc (gunchleoc)]

I have no idea how to fix an already corrupted savegame - those packets are written in a binary format, so it would be really tough.

I am working on a branch that will hopefully fix the issue, but it will make old savegames incompatible too.

[GunChleoc (gunchleoc)]

I thought that keeping flags from doing road-related things in the constructor during saveloading might fix it - it doesn't.

[GunChleoc (gunchleoc)]

Related bug: https://bugs.launchpad.net/widelands/+bug/1762260

[Klaus Halfmann (klaus-halfmann)]

This branchs reworks handling of economies and contains some more assertions:
https://code.launchpad.net/~widelands-dev/widelands/bug-1732765-economy-refactoring/+merge/345277

Unluckily it will break savegame compatibility.
So we mave to close this bug, without proved fixed.

[GunChleoc (gunchleoc)]

Fixed in build20-rc1