src/build_tools/zlib_util.py

# -*- coding: utf-8 -*-
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"""Simple zlib utility."""

import sys
import zlib


def _Read(filename):
  """Reads a file in binary mode."""
  with open(filename, 'rb') as f:
    return f.read()


def _Write(buf, filename):
  """Writes a buffer to a file in binary mode."""
  with open(filename, 'wb') as f:
    f.write(buf)


def Compress(input_filename, output_filename):
  """Compresses a single file by zlib's compression algorithm."""
  _Write(zlib.compress(_Read(input_filename)), output_filename)


def Decompress(input_filename, output_filename):
  """Decompresses a single deflated file."""
  _Write(zlib.decompress(_Read(input_filename)), output_filename)


def main():
  if len(sys.argv) != 4:
    print >>sys.stderr, 'Invalid arguments'
    return
  if sys.argv[1] == 'compress':
    Compress(sys.argv[2], sys.argv[3])
    return
  if sys.argv[1] == 'decompress':
    Decompress(sys.argv[2], sys.argv[3])
    return
  print >>sys.stderr, 'Unknown command:', sys.argv[1]


if __name__ == '__main__':
  main()