i18n mod using gettext tools and logic.

.gitignore

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 *bak*
 tags
 *.vim
+*.mo
 

mods/i18n/README.txt

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+i18n mod for minetest_game, using gettext logic
+===============================================
+
+Into init.lua some parts of code were originally released as WTFPL or
+as public domain. See init.lua for details.
+
+-------------------------------------------------
+Remaining code is released with following license
+-------------------------------------------------
+
+Copyright (C) 2015 netfab <netbox253@gmail.com>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+http://www.gnu.org/licenses/lgpl-2.1.html
+
+
+------------------------------------
+How do I enable i18n in my foo mod ?
+------------------------------------
+ 0 - You need following gettext tools on your system to use scripts/i18n.sh
+ bash script :
+ 	- xgettext
+	- msgfmt
+
+ 1 - Add i18n dependency to mods/foo/depends.txt
+
+ 2 - In your code, set strings as translatable.
+ Example (in patch format) :
+
+-	minetest.chat_send_player(name, "You can only sleep at night.")
++	minetest.chat_send_player(name, _("You can only sleep at night."))
+
+ 3 - In mods/foo/init.lua, load *your own* mo file by using
+ i18n.load_mo_file() function :
+
+	local modpath = minetest.get_modpath("foo")
++	i18n.load_mo_file(modpath, "foo")
+
+ Above example is loading :
+
+	mods/foo/i18n/«language_code»/foo.mo
+
+ Language_code is auto-detected from minetest language setting, or from LANG
+ env variable. Default is : en
+
+ 4 - Generate a po template file that will be usable by translators :
+
+	$ cd scripts/
+	$ bash i18n.sh --po-templates
+	entering ../mods/foo ... created i18n/template.po
+
+ For each mod which depends on the i18n mod, this script will create an i18n/
+ directory and will (re)generate a template.po file. Each mod will have its
+ own i18n/template.po.
+
+ 5 - Prepare translation file (for example in french) :
+
+	$ cd mods/foo/i18n/
+	$ mkdir fr
+	$ cp template.po fr/foo.po
+
+ Now you can translate strings from mods/foo/i18n/fr/foo.po
+
+
+-------------------------------------------
+How do I build all mo files for packaging ?
+-------------------------------------------
+	$ cd scripts/
+	$ bash i18n.sh --build-mo
+	../mods/foo/i18n/fr/foo.po : 9 translated messages.
+	../mods/bar/i18n/fr/bar.po : 7 translated messages.
+

mods/i18n/init.lua

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+-- minetest_game/mods/i18n/init.lua
+
+i18n = {}
+i18n.hash = {}
+
+-- Following 4 lines coming from https://github.com/kaeza/minetest-intllib
+-- (released as WTFPL)
+local LANG = minetest.setting_get("language")
+if not (LANG and (LANG ~= "")) then LANG = os.getenv("LANG") end
+if not (LANG and (LANG ~= "")) then LANG = "en" end
+i18n.LANG = LANG:sub(1, 2)
+
+function i18n.gettext(text)
+	return i18n.hash[text] or text
+end
+
+_=assert(i18n.gettext)
+
+--
+-- Original load_mo_file() function coming from :
+-- 	http://lua-users.org/lists/lua-l/2010-04/msg00005.html
+-- (released as public domain)
+--
+-- Function sligthly modified, original comment is below.
+--
+-----------------------------------------------------------
+-- load an mo file and return a lua table
+-- @param mo_file name of the file to load
+-- @return table on success
+-- @return nil,string on failure
+-- @copyright J.Jorgen von Bargen
+-- @licence I provide this as public domain
+-- @see http://www.gnu.org/software/hello/manual/gettext/MO-Files.html
+-----------------------------------------------------------
+
+function i18n.load_mo_file(modpath, modname)
+	local mo_file = modpath.."/i18n/"..i18n.LANG.."/"..modname..".mo"
+
+	--------------------------------
+	-- open file and read data
+	--------------------------------
+	local fd,err=io.open(mo_file,"rb")
+	if not fd then return nil,err end
+	local mo_data=fd:read("*all")
+	fd:close()
+ 
+	--------------------------------
+	-- precache some functions
+	--------------------------------
+	local byte=string.byte
+	local sub=string.sub
+ 
+	--------------------------------
+	-- check format
+	--------------------------------
+	local peek_long --localize
+	local magic=sub(mo_data,1,4)
+	-- intel magic 0xde120495
+	if magic=="\222\018\004\149" then
+		peek_long=function(offs)
+			local a,b,c,d=byte(mo_data,offs+1,offs+4)
+			return ((d*256+c)*256+b)*256+a
+		end
+	-- motorola magic = 0x950412de
+	elseif magic=="\149\004\018\222" then
+		peek_long=function(offs)
+			local a,b,c,d=byte(mo_data,offs+1,offs+4)
+			return ((a*256+b)*256+c)*256+d
+		end
+	else
+		return nil,"no valid mo-file"
+	end
+ 
+	--------------------------------
+	-- version
+	--------------------------------
+	local V=peek_long(4)
+	if V~=0 then
+		return nul,"unsupported version"
+	end
+ 
+	------------------------------
+	-- get number of offsets of table
+	------------------------------
+	local N,O,T=peek_long(8),peek_long(12),peek_long(16)
+	------------------------------
+	-- traverse and get strings
+	------------------------------
+	local hash={}
+	for nstr=1,N do
+		local ol,oo=peek_long(O),peek_long(O+4) O=O+8
+		local tl,to=peek_long(T),peek_long(T+4) T=T+8
+		hash[sub(mo_data,oo+1,oo+ol)]=sub(mo_data,to+1,to+tl)
+	end
+--	return function(text)
+--		return hash[text] or text
+--	end
+	i18n.hash = hash	
+end
+

scripts/i18n.sh

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+#!/bin/bash
+#
+# i18n.sh -- Shell script to update/build gettext files
+#         -- Released with minetest_game mods/i18n mod
+#
+# Copyright (C) 2015 netfab <netbox253@gmail.com>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License as published by
+# the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+#
+
+ROOT_DIRECTORY=..
+
+function display_help() {
+	echo
+	echo "Usage :"
+	echo " $ $0 --po-templates"
+	echo " $ $0 --build-mo"
+	echo
+	echo "If your mod depends on the i18n mod, « --po-templates » will create"
+	echo "an i18n/ directory into your mod path, then it will extract gettext"
+	echo "strings from your lua files. Finally, result will be saved as i18n/template.po"
+	echo
+	echo "« --build-mo » will scan for po files in mods/*/i18n/ subdirs and will"
+	echo "compile them to binary format (using gettext's msgfmt)."
+	echo
+	echo "See also mods/i18n/README.txt."
+	echo
+}
+
+function update_mods_templates() {
+	for MOD_DIR in ${ROOT_DIRECTORY}/mods/*; do
+		depfile="$MOD_DIR/depends.txt"
+		if [[ -f "$depfile" ]]; then
+			i18n=$(grep -c i18n "$depfile")
+			if [[ $i18n -gt 0 ]]; then
+				OLDPWD=$PWD
+				cd "$MOD_DIR" || exit 7
+				echo -n "entering $MOD_DIR ... "
+				mkdir -p i18n || exit 8
+				xgettext -L Lua *.lua --from-code=UTF-8 -o i18n/template.po
+				echo "created i18n/template.po"
+				cd "$OLDPWD" || exit 9
+			fi
+		fi
+	done
+}
+
+function compile_catalogs() {
+	for x in $(find ${ROOT_DIRECTORY}/mods/ -mindepth 4 -name *.po); do
+		pofile=${x##*/}
+		pofile=${pofile:0:-3}
+		filepath=${x%/*}
+		echo -n "${filepath}/${pofile}.po : "
+		msgfmt "${filepath}/${pofile}.po" -cv -o "${filepath}/${pofile}.mo"
+	done
+}
+
+case "$1" in
+	'--po-templates')
+		update_mods_templates
+	;;
+	'--build-mo')
+		compile_catalogs
+	;;
+	*)
+		display_help
+	;;
+esac