view setup_mpatch_cffi.py @ 30232:362740e05460 stable

templater: use unfiltered changelog to calculate shortest() at constant time

cl._partialmatch() can be pretty slow if hidden revisions are involved. This
patch cancels the slowdown introduced by the previous patch by using an
unfiltered changelog, which means shortest(node) isn't always the shortest.

The result isn't perfect, but seems okay as long as shortest(node) is short
enough to type and can be used as an identifier.

  (with hidden revisions)
  % hg log -R hg-committed -r0:20000 -T '{node|shortest}\n' --time > /dev/null
  (.^^) time: real 1.530 secs (user 1.480+0.000 sys 0.040+0.000)
  (.^)  time: real 43.080 secs (user 43.060+0.000 sys 0.030+0.000)
  (.)   time: real 1.680 secs (user 1.650+0.000 sys 0.020+0.000)

from __future__ import absolute_import

import cffi
import os

ffi = cffi.FFI()
mpatch_c = os.path.join(os.path.join(os.path.dirname(__file__), 'mercurial',
                                     'mpatch.c'))
ffi.set_source("_mpatch_cffi", 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()