setup_bdiff_cffi.py

largefiles: when setting/clearing x bit on largefiles, don't change other bits

It is only the X bit that it matters to copy from the standin to the largefile
in the working directory. While it generally doesn't do any harm to copy the
whole mode, it is also "wrong" to copy more than the X bit we care about. It
can make a difference if someone should try to handle largefiles differently,
such as marking them read-only.

Thus, do similar to what utils.setflags does and set the X bit where there are
R bits and obey umask.

from __future__ import absolute_import

import cffi
import os

ffi = cffi.FFI()
ffi.set_source("_bdiff_cffi",
    open(os.path.join(os.path.join(os.path.dirname(__file__), 'mercurial'),
        'bdiff.c')).read(), include_dirs=['mercurial'])
ffi.cdef("""
struct bdiff_line {
    int hash, n, e;
    ssize_t len;
    const char *l;
};

struct bdiff_hunk;
struct bdiff_hunk {
    int a1, a2, b1, b2;
    struct bdiff_hunk *next;
};

int bdiff_splitlines(const char *a, ssize_t len, struct bdiff_line **lr);
int bdiff_diff(struct bdiff_line *a, int an, struct bdiff_line *b, int bn,
    struct bdiff_hunk *base);
void bdiff_freehunks(struct bdiff_hunk *l);
void free(void*);
""")

if __name__ == '__main__':
    ffi.compile()