view mercurial/cffi/mpatchbuild.py @ 35035:96dcc78468e3 stable

tr-summary: keep a weakref to the unfiltered repository

Repoview can have a different life cycle, causing issue in some corner
cases. The particular instance that revealed this comes from localpeer. The
localpeer hold a reference to the unfiltered repository, but calling 'local()'
will create an on-demand 'visible' repoview. That repoview can be garbaged
collected any time. Here is a simplified step by step reproduction::

    1) tr = peer.local().transaction('foo')
    2) tr.close()

After (1), the repoview object is garbage collected, so weakref used in (2)
point to nothing.


Thanks to Sean Farley for helping raising and debugging this issue.

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'))
ffi.set_source("mercurial.cffi._mpatch", open(mpatch_c).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()