lmihaig / rockzip

rockzip

primitive implementation of gunzip

rockzip is a python CLI tool to compress and decompress files in the gzip format.

First use: pip install -r requirements.txt

Usage:

$ python rockzip.py --help
Usage: rockzip.py [OPTIONS] FILENAME

  Compress or decompress FILENAME. By default FILENAME.gz is created; use -o
  to specify output filename.

Arguments:
  FILENAME  file to de/compress  [required]

Options:
  -d       decompress mode
  -c       compress mode
  -o TEXT  file to output result to
  -k       keep input file [default False]
  --help   Show this message and exit.

only implemented DEFLATE algorithm only implemented block type 2 compression (dynamic huffman codes) and only in one big block (and block type 0 which is uncompressed)

corpus:

• caragiale.txt : Nuvele volume of Ion Luca Caragiale as provided by Project Gutenberg Org
• shakespare.txt : The Complete Works of William Shakespeare as provided by Project Gutenberg Org
• kennedy.xls : Excel spreadsheet
• samba.tar : Tarred source code of Samba 2-2.3

algorithms to test:

• gzip
• brotli
• zopfli
• snappy
• lz4
• lzma
• bzip2
• zstd
• lzfse sau lzopt doar una dintre ele
• xz

bibliography:

• https://datatracker.ietf.org/doc/html/rfc1952
• https://datatracker.ietf.org/doc/html/rfc1951
• https://www.youtube.com/watch?v=oi2lMBBjQ8s
• https://youtu.be/SJPvNi4HrWQ
• http://www.codersnotes.com/notes/elegance-of-deflate/

note: this is a very bad implementation from a performance point of view, it should serve as purely educational