diff options
Diffstat (limited to 'tools/crashreporter/system-symbols/mac/parse_pbzx.py')
| -rwxr-xr-x | tools/crashreporter/system-symbols/mac/parse_pbzx.py | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/tools/crashreporter/system-symbols/mac/parse_pbzx.py b/tools/crashreporter/system-symbols/mac/parse_pbzx.py new file mode 100755 index 0000000000..242a58608e --- /dev/null +++ b/tools/crashreporter/system-symbols/mac/parse_pbzx.py @@ -0,0 +1,107 @@ +#!/usr/bin/env python +# This code is from https://gist.github.com/pudquick/ff412bcb29c9c1fa4b8d +# +# v2 pbzx stream handler +# My personal writeup on the differences here: +# https://gist.github.com/pudquick/29fcfe09c326a9b96cf5 +# +# Pure python reimplementation of .cpio.xz content extraction from pbzx file +# payload originally here: +# http://www.tonymacx86.com/general-help/135458-pbzx-stream-parser.html +# +# Cleaned up C version (as the basis for my code) here, thanks to Pepijn Bruienne / @bruienne +# https://gist.github.com/bruienne/029494bbcfb358098b41 +# +# The python version of this code does not have an explicit license, but +# is based on GPLv3 C code linked above. +# +# 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 3 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, see <https://www.gnu.org/licenses/>. + +from __future__ import absolute_import + +import struct +import sys + + +def seekread(f, offset=None, length=0, relative=True): + if offset is not None: + # offset provided, let's seek + f.seek(offset, [0, 1, 2][relative]) + if length != 0: + return f.read(length) + + +def parse_pbzx(pbzx_path): + section = 0 + xar_out_path = "%s.part%02d.cpio.xz" % (pbzx_path, section) + f = open(pbzx_path, "rb") + # pbzx = f.read() + # f.close() + magic = seekread(f, length=4) + if magic != "pbzx": + raise "Error: Not a pbzx file" + # Read 8 bytes for initial flags + flags = seekread(f, length=8) + # Interpret the flags as a 64-bit big-endian unsigned int + flags = struct.unpack(">Q", flags)[0] + xar_f = open(xar_out_path, "wb") + while flags & (1 << 24): + # Read in more flags + flags = seekread(f, length=8) + flags = struct.unpack(">Q", flags)[0] + # Read in length + f_length = seekread(f, length=8) + f_length = struct.unpack(">Q", f_length)[0] + xzmagic = seekread(f, length=6) + if xzmagic != "\xfd7zXZ\x00": + # This isn't xz content, this is actually _raw decompressed cpio_ + # chunk of 16MB in size... + # Let's back up ... + seekread(f, offset=-6, length=0) + # ... and split it out ... + f_content = seekread(f, length=f_length) + section += 1 + decomp_out = "%s.part%02d.cpio" % (pbzx_path, section) + g = open(decomp_out, "wb") + g.write(f_content) + g.close() + # Now to start the next section, which should hopefully be .xz + # (we'll just assume it is ...) + xar_f.close() + section += 1 + new_out = "%s.part%02d.cpio.xz" % (pbzx_path, section) + xar_f = open(new_out, "wb") + else: + f_length -= 6 + # This part needs buffering + f_content = seekread(f, length=f_length) + tail = seekread(f, offset=-2, length=2) + xar_f.write(xzmagic) + xar_f.write(f_content) + if tail != "YZ": + xar_f.close() + raise "Error: Footer is not xar file footer" + try: + f.close() + xar_f.close() + except BaseException: + pass + + +def main(): + parse_pbzx(sys.argv[1]) + + +if __name__ == "__main__": + main() |