Am 13.10.18 um 04:46 schrieb Jeff King:
But no, right before that we have this line:
offset -= win->offset;
So offset is in fact no longer its original meaning of "offset into the
packfile", but is now an offset of the specific request into the window
we found.
So I think it's correct, but it sure confused me. I wonder if another
variable might help, like:
size_t offset_in_window;
...
/*
* We know this difference will fit in a size_t, because our mmap
* window by * definition can be no larger than a size_t.
*/
offset_in_window = xsize_t(offset - win->offset);
if (left)
*left = win->len - offset_in_window;
return win->base + offset_in_window;
I dunno. Maybe it is overkill.
Thank you for your analysis. No, I don't think that such a new variable
would be overkill. It is important to make such knowledge of value
magnitudes explicit precisely because it reduces confusion and helps
reviewers of the code verify correctness.
-- Hannes
