Lua-iconv

Perform character set conversions in Lua

(c) 2005-11 Alexandre Erwin Ittner alexandre@ittner.com.br

Introduction

Lua-iconv provides POSIX 'iconv' bindings for the Lua Programming Language. The iconv library converts a sequence of characters from one codeset into a sequence of corresponding characters in another codeset. The codesets are those specified in the iconv.new() call that returned the conversion descriptor, cd.

Lua-iconv 7 requires Lua 5.1 or Lua 5.2. For Lua 5.0, use the first release (lua-iconv-r1).

Details on iconv may be obtained in the Open Group's interface definition.

Download and installation

Lua-iconv can be obtained from its GitHub project page, from a LuaRocks server, or from some Linux distributions which already provide it (eg. Debian).

Unless you downloaded a compiled package, you must build the library for your system. If you have LuaRocks installed, all the process is automatic; just fire up your favourite shell and type, as root:

luarocks install lua-iconv

and the package will be downloaded from a rock server, installed and configured. Otherwise, you must compile and install the package. In a system with pkg-config (as many Linux distributions and Unix flavors) open a shell, untar the distribution package and, within the program directory, type:

make install

as root. The library will be compiled and installed on the in the correct path (which is defined in lua5.x.pc). Compiling on systems without pkg-config requires manual changes in the Makefile (this includes Windows).

Loading and initialization

Lua-iconv is a shared library that must be loaded in the Lua interpreter before use. You can simply do a

local iconv = require("iconv")

call to load up the library (that, of course, must be installed in a directory from package.cpath).

API documentation

cd, err = iconv.new(to, from)
cd, err = iconv.open(to, from)

Opens a new conversion descriptor, from the 'from' charset to the 'to' charset. Concatenating "//TRANSLIT" to the first argument will enable character transliteration and concatenating "//IGNORE" to the first argument will cause iconv to ignore any invalid characters found in the input string.

The error code, may have any of the following values:

• nil

  No error. Creation was successful.

• iconv.ERROR_INVALID

  The conversion from from to to is not supported by the implementation.

• iconv.ERROR_UNKNOWN

  There was an unknown error.

This function returns a new converter or nil+err on error.

nstr, err = cd:iconv(str)

Converts the 'str' string to the desired charset. This method always returns two arguments: the converted string and an error code, which may have any of the following values:

• nil

  No error. Conversion was successful.

• iconv.ERROR_NO_MEMORY

  Failed to allocate enough memory in the conversion process.

• iconv.ERROR_INVALID

  An invalid character was found in the input sequence.

• iconv.ERROR_INCOMPLETE

  An incomplete character was found in the input sequence.

• iconv.ERROR_FINALIZED

  Trying to use an already-finalized converter. This usually means that the user was tweaking the garbage collector private methods.

• iconv.ERROR_UNKNOWN

  There was an unknown error.

License

Lua-iconv is copyrighted free software: it can be used for both academic and commercial purposes at absolutely no cost. There are no royalties or GNU-like "copyleft" restrictions. The legal details are below:

Lua-iconv is (c) 2005-11 Alexandre Erwin Ittner

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHOR OR COPYRIGHT HOLDER BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

If you use this package in a product, an acknowledgment in the product documentation would be greatly appreciated (but it is not required).