mercurial/cffi/mpatchbuild.py

commit: tell user what to do with .hg/last-message.txt

I have always assumed that the message will be reused by the next `hg
commit`, but it seems it's just silently dropped on the next
commit. Let's try to be more helpful by telling the user that they
have to manually tell hg to reuse it.

The file will still be lost if the user runs some other operation in
between (like a non-in-memory rebase). That will be fixed once we've
switched all operations to be in-memory :)

I didn't include `$(hg root)/` in the path in the message to the user
because that would have made the message too long. Hopefully the user
will figure that part out themselves.

Differential Revision: https://phab.mercurial-scm.org/D8463

from __future__ import absolute_import

import cffi
import os

ffi = cffi.FFI()
mpatch_c = os.path.join(
    os.path.join(os.path.dirname(__file__), '..', 'mpatch.c')
)
with open(mpatch_c) as f:
    ffi.set_source(
        "mercurial.cffi._mpatch", f.read(), include_dirs=["mercurial"]
    )
ffi.cdef(
    """

struct mpatch_frag {
       int start, end, len;
       const char *data;
};

struct mpatch_flist {
       struct mpatch_frag *base, *head, *tail;
};

extern "Python" struct mpatch_flist* cffi_get_next_item(void*, ssize_t);

int mpatch_decode(const char *bin, ssize_t len, struct mpatch_flist** res);
ssize_t mpatch_calcsize(size_t len, struct mpatch_flist *l);
void mpatch_lfree(struct mpatch_flist *a);
static int mpatch_apply(char *buf, const char *orig, size_t len,
                        struct mpatch_flist *l);
struct mpatch_flist *mpatch_fold(void *bins,
                       struct mpatch_flist* (*get_next_item)(void*, ssize_t),
                       ssize_t start, ssize_t end);
"""
)

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