checksum: calculating a save's checksum about d2d2s HOT 5 CLOSED

looks, like the game doesn't read a files only because of this issue.

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also, the code actually calculates a checksum here but sadly in a wrong way 😢
here is also a checksum description

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thrugg_aka_trogg on discord

I also used https://github.com/krisives/d2s-format#checksum as a reference

the way I did the checksum calc was
https://github.com/pairofdocs/d2s_edit_recalc/blob/master/edit_and_recalc.py#L11-L18

so I think if you set the four bytes of data[i] where the checksum is placed to 00s that calculation should work

data[12:16] = 0

// then the for-loop

        var sum uint32
        for i := range data {
		sum <<= 1
		sum += uint32(data[i])
	}

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@pairofdocs thanks for link to your repo. I'll take a look.

I think, that I'm doing something wrong, because my checksum isn't equal to base sum but data are.
The game doesn't want to read my saves.

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@pairofdocs I fixed it with your code! thanx a lot!
the problem was, that sum <<= 1 wasn't correct. this expression should look like:

                sum = ((sum << 1) % math.MaxUint32) | (sum >> (int32Size*byteLen - 1))

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