Mercurial > hg
view mercurial/cffi/bdiff.py @ 47387:75e1104f23a2
revlog: use dedicated code for reading sidedata
We are about to introduce a new, dedicated, file to store sidedata. Before doing so, we make sidedata reading go through different code as reading data chunk. This will simplify some of the complexity of the next changesets.
The reading is very simple right now and will need some improvement later to
reuse some of the caching strategy we use for the data file.
Differential Revision: https://phab.mercurial-scm.org/D10785
author | Pierre-Yves David <pierre-yves.david@octobus.net> |
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date | Thu, 27 May 2021 04:09:30 +0200 |
parents | 521ac0d7047f |
children | 6000f5b25c9b |
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# bdiff.py - CFFI implementation of bdiff.c # # Copyright 2016 Maciej Fijalkowski <fijall@gmail.com> # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. from __future__ import absolute_import import struct from ..pure.bdiff import * from . import _bdiff # pytype: disable=import-error ffi = _bdiff.ffi lib = _bdiff.lib def blocks(sa, sb): a = ffi.new(b"struct bdiff_line**") b = ffi.new(b"struct bdiff_line**") ac = ffi.new(b"char[]", str(sa)) bc = ffi.new(b"char[]", str(sb)) l = ffi.new(b"struct bdiff_hunk*") try: an = lib.bdiff_splitlines(ac, len(sa), a) bn = lib.bdiff_splitlines(bc, len(sb), b) if not a[0] or not b[0]: raise MemoryError count = lib.bdiff_diff(a[0], an, b[0], bn, l) if count < 0: raise MemoryError rl = [None] * count h = l.next i = 0 while h: rl[i] = (h.a1, h.a2, h.b1, h.b2) h = h.next i += 1 finally: lib.free(a[0]) lib.free(b[0]) lib.bdiff_freehunks(l.next) return rl def bdiff(sa, sb): a = ffi.new(b"struct bdiff_line**") b = ffi.new(b"struct bdiff_line**") ac = ffi.new(b"char[]", str(sa)) bc = ffi.new(b"char[]", str(sb)) l = ffi.new(b"struct bdiff_hunk*") try: an = lib.bdiff_splitlines(ac, len(sa), a) bn = lib.bdiff_splitlines(bc, len(sb), b) if not a[0] or not b[0]: raise MemoryError count = lib.bdiff_diff(a[0], an, b[0], bn, l) if count < 0: raise MemoryError rl = [] h = l.next la = lb = 0 while h: if h.a1 != la or h.b1 != lb: lgt = (b[0] + h.b1).l - (b[0] + lb).l rl.append( struct.pack( b">lll", (a[0] + la).l - a[0].l, (a[0] + h.a1).l - a[0].l, lgt, ) ) rl.append(str(ffi.buffer((b[0] + lb).l, lgt))) la = h.a2 lb = h.b2 h = h.next finally: lib.free(a[0]) lib.free(b[0]) lib.bdiff_freehunks(l.next) return b"".join(rl)