https://github.com/keithj/deoxybyte-gzip

Common Lisp interface to zlib via CFFI.
https://github.com/keithj/deoxybyte-gzip

Last synced: 2 days ago
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Common Lisp interface to zlib via CFFI.

• Host: GitHub
• URL: https://github.com/keithj/deoxybyte-gzip
• Owner: keithj
• License: gpl-3.0
• Created: 2009-11-17T23:51:17.000Z (about 15 years ago)
• Default Branch: devel
• Last Pushed: 2024-12-26T17:36:55.000Z (about 1 month ago)
• Last Synced: 2024-12-26T18:28:05.979Z (about 1 month ago)
• Language: Common Lisp
• Homepage:
• Size: 289 KB
• Stars: 5
• Watchers: 3
• Forks: 4
• Open Issues: 1
• Metadata Files:
  • Readme: README.txt
  • License: LICENSE.txt

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• trackawesomelist - deoxybyte-gzip (⭐7) - Common Lisp interface to zlib via CFFI. GPL3. (Recently Updated / [Who Wants to Be a Millionare](https://www.boardgamecapital.com/who-wants-to-be-a-millionaire-rules.htm))

README

        
Introduction

This system provides gzip and gunzip functions and a Gray-streams

implementation, both built on a set of lower-level zlib functions.

Functions are provided for inflating and deflating to and from Lisp

octet vectors and Lisp octet streams, which may be tuned using the

Zlib tuning parameters described in the Zlib C function deflateInit2.

In addition, a basic implementation of the data structure described in

RFC1952 is included, allowing a hybrid approach to reading gzip data,

using native Lisp streams and Zlib inflate/deflate.

Measuring execution times of the gz:gzip and gz:gunzip functions shows

deoxybyte-gzip to be fractionally slower than gzip, but over 3x slower

than gunzip.

Relative execution time (SBCL 1.0.40 X86-64):

                  gzip   deoxybyte-gzip     gzip-stream

  Compression      1.0             1.1             1.1

Decompression      1.0             3.1             3.5

Timings were taken compressing and decompressing a 1.8 Gb text file

using gzip/gunzip command line programs, the gz:gzip/gz:gunzip

functions (which use an internal buffer of length 2^16 -1) and the

Gray streams classes using

gz:stream-read-sequence/gz:stream-write-sequence methods. A zlib

compression level of 6 was used.

This system is named with a deoxybyte- prefix because there are

several existing Common Lisp packages using the gzip name and I don't

want to clash with them.

Installation

deoxybyte-gzip uses ASDF for system definition. Copy or symlink

deoxybyte-gzip.asd (and optionally deoxybyte-gzip-test.asd) to your

asdf:*central-registry* and load deoxybyte-io with the asdf:operate

function:

 (asdf:operate 'asdf:load-op :deoxybyte-gzip)

or with the equivalent deoxybyte-systems:load-system function:

 (dxs:load-system :deoxybyte-gzip)

Tests

To run the unit and regression tests you need to have LIFT

installed. Run the tests with the asdf:operate function:

 (asdf:operate 'asdf:test-op :deoxybyte-gzip)

or with the equivalent deoxybyte-systems:test-system function:

 (dxs:test-system :deoxybyte-gzip)

Documentation

See the Lisp docstrings, particularly the package docstrings for an

overview. HTML documentation may be generated with the command:

 (dxs:document-system :deoxybyte-gzip)

at the REPL, provided that CLDOC is installed.

Dependencies

deoxybyte-systems       git://github.com/keithj/deoxybyte-systems.git

deoxybyte-io            git://github.com/keithj/deoxybyte-io.git

Optional dependencies

LIFT                    http://common-lisp.net/project/lift/

CLDOC                   http://common-lisp.net/project/cldoc/