A jpeg causes img2sixel to crash with an integer overflow

[DavidGriffith]

$ sixel2png lolwut.jpg
runtime error: integer overflow
safe_addition_for_params: ingeger overflow detected.

And here's the image that provokes this error.

No, I'm not kidding. I went through a few of my favorite images and img2sixel barfed on this one.

[j4james]

I think this is just a user error. The initial instructions at the top of the issue suggest you were calling sixel2png rather than img2sixel. As far as I can tell img2sixel has no problem converting this image, and it's understandable that sixel2png would fail, because the source file isn't sixel!

The code is trying desperately to find something that looks like sixel in that jpeg file, but at some point it comes across a sequence of digits that it thinks is a numeric parameter, but the number is far too big, so it gives up and reports an error. This is just a regular error report rather than a crash, so I believe it's working as expected.