/brz/remove-bazaar

# (C) 2005 Matt Mackall

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

import difflib, sys, struct

def linesplit(a):

    al, ap = [], []

    last = 0

    n = a.find("\n") + 1

    while n > 0:

        ap.append(last)

        al.append(a[last:n])

        last = n

        n = a.find("\n", n) + 1

    return (al, ap)

def diff(a, b):

    (al, ap) = linesplit(a)

    (bl, bp) = linesplit(b)

    d = difflib.SequenceMatcher(None, al, bl)

    ops = []

    for o, m, n, s, t in d.get_opcodes():

        if o == 'equal': continue

        ops.append((ap[m], ap[n], "".join(bl[s:t])))

    return ops

def tobinary(ops):

    b = ""

    for f in ops:

        b += struct.pack(">lll", f[0], f[1], len(f[2])) + f[2]

    return b

def bdiff(a, b):

    return tobinary(diff(a, b))

def patch(t, ops):

    last = 0

    r = []

    for p1, p2, sub in ops:

        r.append(t[last:p1])

        r.append(sub)

        last = p2

    r.append(t[last:])

    return "".join(r)

def frombinary(b):

    ops = []

    while b:

        p = b[:12]

        m, n, l = struct.unpack(">lll", p)

        ops.append((m, n, b[12:12 + l]))

        b = b[12 + l:]

    return ops

def bpatch(t, b):

    return patch(t, frombinary(b))