64 lines
2.0 KiB
Python
64 lines
2.0 KiB
Python
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#!/usr/bin/env python
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# Copyright (c) 2012 The Chromium Authors. All rights reserved.
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# Use of this source code is governed by a BSD-style license that can be
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# found in the LICENSE file.
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"""Extracts a single file from a CAB archive."""
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import os
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import shutil
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import subprocess
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import sys
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import tempfile
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def run_quiet(*args):
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"""Run 'expand' supressing noisy output. Returns returncode from process."""
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popen = subprocess.Popen(args, stdout=subprocess.PIPE)
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out, _ = popen.communicate()
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if popen.returncode:
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# expand emits errors to stdout, so if we fail, then print that out.
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print out
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return popen.returncode
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def main():
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if len(sys.argv) != 4:
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print 'Usage: extract_from_cab.py cab_path archived_file output_dir'
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return 1
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[cab_path, archived_file, output_dir] = sys.argv[1:]
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# Expand.exe does its work in a fixed-named temporary directory created within
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# the given output directory. This is a problem for concurrent extractions, so
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# create a unique temp dir within the desired output directory to work around
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# this limitation.
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temp_dir = tempfile.mkdtemp(dir=output_dir)
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try:
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# Invoke the Windows expand utility to extract the file.
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level = run_quiet('expand', cab_path, '-F:' + archived_file, temp_dir)
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if level == 0:
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# Move the output file into place, preserving expand.exe's behavior of
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# paving over any preexisting file.
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output_file = os.path.join(output_dir, archived_file)
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try:
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os.remove(output_file)
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except OSError:
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pass
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os.rename(os.path.join(temp_dir, archived_file), output_file)
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finally:
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shutil.rmtree(temp_dir, True)
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if level != 0:
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return level
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# The expand utility preserves the modification date and time of the archived
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# file. Touch the extracted file. This helps build systems that compare the
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# modification times of input and output files to determine whether to do an
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# action.
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os.utime(os.path.join(output_dir, archived_file), None)
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return 0
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if __name__ == '__main__':
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sys.exit(main())
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