xdiff: remove unused xpp and xecfg parameters
They are unused. Thus removed.
Differential Revision: https://phab.mercurial-scm.org/D2764
xdiff: remove unused flags parameter
After D2683, the flags parameter in some functions is no longer needed.
Thus removed.
Differential Revision: https://phab.mercurial-scm.org/D2763
xdiff: replace {unsigned ,}long with {u,}int64_t
MSVC treats "long" as 4-byte. That could cause overflows since the xdiff
code uses "long" in places where "size_t" or "ssize_t" should be used.
Let's use explicit 8 byte integers to avoid
FWIW git avoids that overflow by limiting diff size to 1GB [1]. After
examining the code, I think the remaining risk (the use of "int") is low
since "int" is only used for return values and hash table size. Although a
wrong hash table size would not affect the correctness of the code, but that
could make the code extremely slow. The next patch will change hash table
size to 8-byte integer so the 1GB limit is unlikely needed.
This patch was done by using `sed`.
[1]: https://github.com/git/git/commit/
dcd1742e56ebb944c4ff62346da4548e1e3be67
Differential Revision: https://phab.mercurial-scm.org/D2762
xdiff: add comments for fields in xdfile_t
This makes the related code easier to understand.
Differential Revision: https://phab.mercurial-scm.org/D2685