detools 0.3.0

Binary delta encoding utility.

About

Binary delta encoding utility in Python 3, using C extensions.

Based on http://www.daemonology.net/bsdiff/, with the following differences:

• LZMA compression instead of BZ2 for smaller patches.

• Linear patch file access pattern to allow streaming.

• SA-IS instead of qsufsort for speed and reliability.

Project homepage: https://github.com/eerimoq/detools

Documentation: http://detools.readthedocs.org/en/latest

Installation

pip install detools

Statistics

To compressed is the size of To file compressed using lzma --best.

All sizes are in bytes.

From file	To file	From size	To size	Patch size	To compressed
micropython v1.9.4	micropython v1.10	604872	615388	73532	367500
python 3.5	python 3.6	4464400	4568920	1493488	1402663
foo.old	foo.new	2780	2780	192	1934

Example usage

Command line tool

The create patch subcommand

Create a patch foo.patch from tests/files/foo.old to tests/files/foo.new.

$ detools create_patch tests/files/foo.old tests/files/foo.new foo.patch
$ ls -l foo.patch
-rw-rw-r-- 1 erik erik 192 feb 21 07:28 foo.patch

The apply patch subcommand

Apply the patch foo.patch to tests/files/foo.old to create foo.new.

$ detools apply_patch tests/files/foo.old foo.patch foo.new
$ ls -l foo.new
-rw-rw-r-- 1 erik erik 2780 feb 21 07:30 foo.new

Contributing

1. Fork the repository.

2. Implement the new feature or bug fix.

3. Implement test case(s) to ensure that future changes do not break legacy.

4. Run the tests.

   make test

5. Create a pull request.