= libcdb-ruby - Ruby bindings for CDB Constant Databases.

== VERSION

This documentation refers to libcdb-ruby version 0.2.1


== DESCRIPTION

The libcdb-ruby library provides Ruby bindings for the
TinyCDB[http://www.corpit.ru/mjt/tinycdb.html] package for
creating and reading {constant databases}[http://cr.yp.to/cdb.html].

  require 'libcdb'

  # creating
  LibCDB::CDB.open('foo.cdb', 'w') { |cdb|
    cdb['a'] = 'one'
    cdb['b'] = '123'
  }

  # reading
  LibCDB::CDB.open('foo.cdb') { |cdb|
    cdb['a']  #=> "one"
    cdb['b']  #=> "123"
    cdb['c']  #=> nil
  }

  # hybrid
  LibCDB::CDB.open('foo.cdb', 'w+') { |cdb|
    cdb['a'] = 'one'
    cdb['b'] = '123'

    cdb['a']  #=> "one"
    cdb['b']  #=> "123"
    cdb['c']  #=> nil

    # database is truncated whenever
    # a new writer is opened:
    cdb['a'] = 'two'
    cdb['c'] = 'xyz'

    cdb['a']  #=> "two"
    cdb['b']  #=> nil
    cdb['c']  #=> "xyz"
  }

  # update existing database
  LibCDB::CDB.open('foo.cdb', 'r+') { |cdb|
    # store existing records
    cdb << cdb.to_h

    # and add a new one
    cdb['d'] = '42'

    cdb['a']  #=> "two"
    cdb['b']  #=> nil
    cdb['c']  #=> "xyz"
    cdb['d']  #=> "42"
  }


== PREREQUISITES

* Ruby 1.9+ (see {below}[rdoc-label:label-SUPPORTED+PLATFORMS] for details)
* TinyCDB[http://www.corpit.ru/mjt/tinycdb.html] headers (not needed when
  installing the fat binary gem on Windows)

  Debian/Ubuntu:: +libcdb-dev+
  Fedora/SuSE::   +tinycdb-devel+
  Gentoo::        +dev-db/tinycdb+


== SUPPORTED PLATFORMS

Linux::   MRI 1.9.3, 2.0 & 2.1 (Tested on 64-bit Ubuntu GNU/Linux
          with 1.9.3p550, 2.0.0p594 and 2.1.5p273)
Windows:: MRI 1.9.3 (Tested on 32-bit Windows XP with 1.9.3p194)


== LINKS

CDB::           http://cr.yp.to/cdb.html
TinyCDB::       http://www.corpit.ru/mjt/tinycdb.html
Documentation:: https://blackwinter.github.com/libcdb-ruby
Source code::   https://github.com/blackwinter/libcdb-ruby
RubyGem::       https://rubygems.org/gems/libcdb-ruby
Travis CI::     https://travis-ci.org/blackwinter/libcdb-ruby


== AUTHORS

* Jens Wille <mailto:[email protected]>


== CREDITS

This project was inspired by ruby-cdb[https://github.com/mbj/ruby-cdb] and
cdb-full[https://rubygems.org/gems/cdb-full]. The code organization, especially the
extension part, was modeled after libxml-ruby[https://github.com/xml4r/libxml-ruby].

And props to the rake-compiler[http://github.com/luislavena/rake-compiler]
team for making extension building such a breeze :)


== LICENSE AND COPYRIGHT

Copyright (C) 2012 University of Cologne,
Albertus-Magnus-Platz, 50923 Cologne, Germany

Copyright (C) 2013-2016 Jens Wille

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

libcdb-ruby 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 Affero General Public
License for more details.

You should have received a copy of the GNU Affero General Public License
along with libcdb-ruby. If not, see <http://www.gnu.org/licenses/>.