zlib

zlib
1. Description
2. Author
3. Requirements
4. Documentation
  1. Procedures
  2. Examples
    1. Inflating a stream:
    2. Deflating a stream:
5. Notes
6. Source
7. Version
8. License

Description

zlib bindings for Chicken Scheme

zlib is a popular data compression library that uses the DEFLATE algorithm internally. It is defined in RFC 1950.

Note: if you are using a CHICKEN version < 4.8.3 and experiencing unexpected behavior with this egg, check ticket #1033.

Author

Ismay Gay

Requirements

foreigners

miscmacros

Documentation

Procedures

These bindings provide two procedures:

[procedure] (open-zlib-compressed-input-port [INPUT-PORT])

Returns an input-port.

[procedure] (open-zlib-compressed-output-port [OUTPUT-PORT])

Returns an output-port.

The first is for inflating an existing zlib stream and the second for deflating data into a new stream.

Examples

Inflating a stream:

  (with-input-from-port (open-zlib-compressed-input-port)
    read-string)

Deflating a stream:

  (with-output-to-port (open-zlib-compressed-output-port)
    (lambda ()
      (write-string (read-string))
      (close-output-port (current-output-port))))

Notes

This is expecting the zlib format, not raw DEFLATE or the gzip format, which are defined in RFCs 1951 and 1952 respectively. See z3 for DEFLATE and gzip support.
When finished deflating, it is important to always close the zlib output-port. This will ensure that the zlib trailing data is written along with any data still buffered. The destination port will remain open after the zlib port is closed.

Source

Source code is available in the eggs repository as well as on github: https://github.com/r1b/zlib

Version

0.6.1: added missing test dependencies
0.6: Port to chicken 5
0.5.1: added missing dependency to miscmacros
0.5: Initial release

License

 Copyright (C) 2011 by Ismay Gay

 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation; either version 3 of the License, or
 (at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software
 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA

 zlib: Copyright (C) 1995-2010 Jean-loup Gailly and Mark Adler
 see http://zlib.net/zlib_license.html