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−# mpatch.py - CFFI implementation of mpatch.c
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−#
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−# Copyright 2016 Maciej Fijalkowski <fijall@gmail.com>
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−#
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−# This software may be used and distributed according to the terms of the
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−# GNU General Public License version 2 or any later version.
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−
+
−from __future__ import absolute_import
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−
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−from ..pure.mpatch import *
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−from ..pure.mpatch import mpatchError  # silence pyflakes
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−from . import _mpatch
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−
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−ffi = _mpatch.ffi
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−lib = _mpatch.lib
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−
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−@ffi.def_extern()
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−def cffi_get_next_item(arg, pos):
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−    all, bins = ffi.from_handle(arg)
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−    container = ffi.new("struct mpatch_flist*[1]")
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−    to_pass = ffi.new("char[]", str(bins[pos]))
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−    all.append(to_pass)
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−    r = lib.mpatch_decode(to_pass, len(to_pass) - 1, container)
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−    if r < 0:
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−        return ffi.NULL
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−    return container[0]
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−
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−def patches(text, bins):
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−    lgt = len(bins)
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−    all = []
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−    if not lgt:
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−        return text
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−    arg = (all, bins)
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−    patch = lib.mpatch_fold(ffi.new_handle(arg),
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−                            lib.cffi_get_next_item, 0, lgt)
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−    if not patch:
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−        raise mpatchError("cannot decode chunk")
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−    outlen = lib.mpatch_calcsize(len(text), patch)
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−    if outlen < 0:
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−        lib.mpatch_lfree(patch)
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−        raise mpatchError("inconsistency detected")
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−    buf = ffi.new("char[]", outlen)
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−    if lib.mpatch_apply(buf, text, len(text), patch) < 0:
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−        lib.mpatch_lfree(patch)
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−        raise mpatchError("error applying patches")
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−    res = ffi.buffer(buf, outlen)[:]
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−    lib.mpatch_lfree(patch)
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−    return res