From: Nobuyoshi Nakada <nobu@...>
Date: 2009-06-06T23:23:18+09:00
Subject: Re: Iconv and incompatible encodings

Hi,

At Thu, 4 Jun 2009 00:28:25 +0900,
Adam Strzelecki wrote in [ruby-talk:338275]:
> Alternative and light solution is to create own extension as below:

First of all, option after // is GNU iconv local extension.

Second, extconf.rb must check for the necessary header, and
whether each categories are defined.

# extconf.rb
require 'mkmf'
extension_name = 'locale'
header = "locale.h"
dir_config(extension_name)
if have_header(header)
  lc = %w[CTYPE NUMERIC TIME COLLATE MONETARY MESSAGES ALL]
  lc = lc.delete_if {|n| !have_macro("LC_#{n}", header)}.
    collect {|n| "def(#{n.downcase}, LC_#{n})"}.
    join(' ')
  $defs << "-Dforeach_categories(def)=\"#{lc}\""
  create_header
  create_makefile(extension_name)
end

Next, StringValueCStr() is much better than Check_Type().

> ... and use:
> require 'locale'
> Locale::setlocale Locale::LC_CTYPE, ''

And it feels too redundant.  I guess Locale.ctype = '' would be
easy.

/* locale.c */
#include <locale.h>
#include "ruby.h"

static VALUE
rb_setlocale(int category, VALUE locale)
{
    char *r = setlocale(category, StringValueCStr(locale));
    return r ? rb_str_new2(r) : Qnil;
}

static VALUE
rb_getlocale(int category)
{
    char *r = setlocale(category, NULL);
    return r ? rb_str_new2(r) : Qnil;
}

#define funcs(n, c) \
static VALUE rb_getlocale_##n(VALUE self) {return rb_getlocale(c);} \
static VALUE rb_setlocale_##n(VALUE self, VALUE val) {return rb_setlocale(c, val);} \
/* end of funcs */

foreach_categories(funcs)

void
Init_locale(void)
{
    VALUE locale = rb_define_module("Locale");
#define methods(n, c) \
    rb_define_singleton_method(locale, #n, rb_getlocale_##n, 0); \
    rb_define_singleton_method(locale, #n"=", rb_setlocale_##n, 1); \
    /* end of methods */

    foreach_categories(methods);
}

-- 
Nobu Nakada