************************************* * SquirrelMail internationalization * ************************************* $Date$ $Revision$ This document should explain how SquirrelMail internationalization works and provide information about some aspects of implementation. 1. Supported languages 2. $languages array 3. XTRA_CODE functions 4. Display of different charsets 5. IMAP folder names 6. Plural forms 7. Language setup 8. Time zones ------------------------------- 1. Supported languages ------------------------------- Valid language codes are: * ar - Arabic, windows-1256 charset * bg_BG - Bulgarian, windows-1251 charset * bn_IN - Bengali, utf-8 charset * ca_ES - Catalan, iso-8859-1 charset * cs_CZ - Czech, iso-8859-2 charset * cy_GB - Welsh, iso-8859-1 charset * da_DK - Danish, iso-8859-1 charset * de_DE - German, iso-8859-1 charset * el_GR - Greek, iso-8859-7 charset * en_GB - British, iso-8859-15 charset * en_US - English, charset depends on $default_charset * es_ES - Spanish, iso-8859-1 charset * et_EE - Estonian, iso-8859-15 charset * eu_ES - Basque, iso-8859-1 charset * fa_IR - Farsi, utf-8 charset * fi_FI - Finnish, iso-8859-1 charset * fo_FO - Faroese, iso-8859-1 charset * fr_FR - French, iso-8859-1 charset * he_IL - Hebrew, windows-1255 charset * hr_HR - Croatian, iso-8859-2 charset * hu_HU - Hungarian, iso-8859-2 charset * id_ID - Indonesian, iso-8859-1 charset * is_IS - Icelandic, iso-8859-1 charset * it_IT - Italian, iso-8859-1 charset * ja_JP - Japanese, euc-jp charset (emails are created in iso-2022-jp) * ko_KR - Korean, euc-kr charset * lt_LT - Lithuanian, utf-8 charset * ms_MY - Malay, iso-8859-1 charset * nb_NO - Norwegian (Bokmal), iso-8859-1 charset * nl_NL - Dutch, iso-8859-1 charset * nn_NO - Norwegian (Nynorsk), iso-8859-1 charset * pl_PL - Polish, iso-8859-2 charset * pt_BR - Portuguese (Brazil), iso-8859-1 charset * pt_PT - Portuguese (Portugal), iso-8859-1 charset * ro_RO - Romanian, iso-8859-2 charset * ru_UA - Ukrainian Russian, koi8-r charset * ru_RU - Russian, utf-8 charset * sk_SK - Slovak, iso-8859-2 charset * sl_SI - Slovenian, iso-8859-2 charset * sr_YU - Serbian, iso-8859-2 charset * sv_SE - Swedish, iso-8859-1 charset * ug - Uighur, utf-8 charset (some systems don't support Uighur system locale) * th_TH - Thai, tis-620 charset * tl_PH - Tagalog, iso-8859-1 charset (main translation is missing, only some plugins are translated) * tr_TR - Turkish, iso-8859-9 charset * uk_UA - Ukrainian, koi8-u charset * zh_CN - Chinese Simplified, gb2312 charset * zh_TW - Chinese Traditional, big5 charset Charset totals: * iso-8859-1 = 21 * iso-8859-2 = 8 * utf-8 = 5 * iso-8859-15 = 2 * iso-8859-7 = 1 * iso-8859-9 = 1 * koi8-r = 1 * koi8-u = 1 * windows-1251 = 1 * windows-1255 = 1 * windows-1256 = 1 * tis-620 = 1 * gb2312 = 1 * big5 = 1 * euc-jp = 1 * euc-kr = 1 ------------------- 2. $languages array ------------------- $languages array is stored in functions/i18n.php (v. 1.5.0 or older) or locale/*/setup.php files and defines enabled SquirrelMail translations. Format of array: $languages['language_code']['key'] = 'value' Possible array key names: * NAME - Translation name in English. Any 8bit symbols must be html encoded. * CHARSET - Charset used by translation * ALIAS - 'language_code' should contain short language name (iso-639). 'value' should contain name of other 'language_code' that defines translation with NAME and CHARSET keys. Entry links short language form with long form (language+country). See: http://www.loc.gov/standards/iso639-2/langhome.html and http://www.iso.org/iso/en/prods-services/iso3166ma/02iso-3166-code-lists/list-en1.html * ALTNAME - Native translation name. Any 8bit symbols must be html encoded. Name is visible when $show_alternative_names is enabled. * LOCALE - Full locale name (in xx_XX.charset format or other format required by php gettext functions). From 1.4.4/1.5.1 'value' can contain array. If php version is older than 4.3.0, system uses only first locale name listed in array. First locale name must be compatible with FreeBSD system locale names. * DIR - Text direction. Used to define Right-to-Left languages. Possible values 'rtl' or 'ltr'. If undefined - defaults to 'ltr'. * XTRA_CODE - translation uses special functions. (see chapter 3. XTRA_CODE functions) Each 'language_code' definition requires NAME+CHARSET or ALIAS keys. Other keys are optional. ---------------------- 3. XTRA_CODE functions ---------------------- XTRA_CODE functions provide way to change interface behavior, when translation requires special handling of some SquirrelMail functions. Functions are enabled by setting XTRA_CODE option in $languages array and including appropriate functions in locale/language_code/setup.php. First part of function name is word listed in $languages['language_code']['XTRA_CODE'] value. Second part is one of special keywords. Possible keywords: * _decode Used in src/compose.php, src/i18n.php, src/view_text.php, functions/mime.php Requires mbstring support * _encode Used in src/compose.php, src/read_body.php * _encodeheader Used in functions/mime.php Returning function * _decodeheader Used in functions/mime.php Returning function * _downloadfilename Used in functions/mime.php * _utf7_imap_encode Used in functions/imap_utf7_local.php Returning function * _utf7_imap_decode Used in functions/imap_utf7_local.php Returning function * _strimwidth Used in functions/mailbox_display.php Returning function * _wordwrap Used in functions/strings.php (sqWordWrap) -------------------------------- 4. Display of different charsets -------------------------------- When SquirrelMail generates html pages, it uses charset defined in translation selected by end user. Interface can display emails encoded in different charsets. In order to display characters that might be unsupported by user's charset, SquirrelMail uses decoding functions that convert non us-ascii symbols into html entities. All decoding functions are stored in functions/decode/ directory. By default SquirrelMail includes decoding functions that support iso-8859-x, windows-125x, utf-8, us-ascii, koi8-r, koi8-u, tis-620, ns-4551_1, iso-ir-111, cp855 and cp866 charsets. Other decoding functions are distributed in separate packages. Separate packaging of decoding functions is supported from SquirrelMail 1.4.4 and 1.5.0. us-ascii decoding replaces all 8bit symbols with question marks. utf-8 decoding function does not enable decoding of five and six byte utf-8 symbols by default (code is commented) and replaces all incorrectly formated 8bit symbols with question marks. Some decoding functions might require php recode extension or php 4.3+ mbstring extension. If your php installation does not support them, you might be using slower and cpu/memory intensive functions. -------------------- 5. IMAP folder names -------------------- IMAP folder names use UTF7-IMAP charset. Folder names that are stored in conf.pl must be encoded in UTF7-IMAP charset. SquirrelMail uses internal functions that convert folder names from/to utf7-imap charset. By default those functions work with iso-8859-1 charset. Other charsets are supported only when php mbstring extension supports them. TODO: write independent implementation of charset to utf7-imap conversion. --------------- 6. Plural forms --------------- From v.1.5.1 SquirrelMail includes support of plural forms. It allows to use correct translation forms with numbers. For example. "We have %s squirrel on the roof." and "We have %s squirrels on the roof." can be written in one function call without checking actual number for squirrels. Gettext functions also deal with non English languages that might use different word forms for two, five, ten or more units. Support is provided by ngettext functions that exist in php gettext extension from php 4.2.0 and by ngettext function replacements from php-gettext classes (http://savannah.nongnu.org/projects/php-gettext). In order to use it correctly when php gettext extension does not have ngettext support, SquirrelMail uses bindtextdomain and textdomain wrappers that load missing functions. If plugins want to use ngettext functions without increasing php requirements to 4.2.0 with gettext support, they should require SquirrelMail 1.5.1, use sq_bindtextdomain function instead of bindtextdomain and use sq_textdomain function instead of textdomain function. If SquirrelMail wrapper functions are used, there is no need to issue sq_bindtextdomain when plugins reverts to SquirrelMail domain. More information about ngettext and plural forms can be found at: http://www.gnu.org/software/gettext/manual/html_chapter/gettext_10.html#SEC150 ----------------- 7. Language setup ----------------- SquirrelMail uses set_up_language() function to setup language environment. Environment is setup automatically when include/validate.php is loaded. SquirrelMail gets interface language from three places: a) user preference. It is set in Options -> Display Preferences -> Language. preference uses language key. If user's preferences are not available (user is not logged in), system tries to extract language value from 'squirrelmail_language' cookie. b) default squirrelmail language that is set in configuration ($squirrelmail_default_language variable). c) preferred language setting provided by browser. It is used only when default squirrelmail language is set to empty string If language information is not available, SquirrelMail falls back to US English translation. ------------- 8. Time zones ------------- If php install allows modifying environment variable TZ, SquirrelMail allows end users to select different time zone in their preferences. It can be set in Options -> Personal Information -> Your current timezone. Time zone is setup automatically when include/validate.php is loaded. If TZ variable can't be modified (php is running is safe mode and variable is not listed in php safe_mode_allowed_env_vars), user's time zone options are not visible and interface uses default webserver's time zone. SquirrelMail 1.5.0 and older store list of available time zones in locale/timezones.cfg. Since 1.5.1 standard times zones are moved to include/timezones/standard.php and time zone handling differs from older SquirrelMail versions. Time zone configuration is controlled in SquirrelMail configuration utility (conf.pl), 4. General Options -> 15. Time zone configuration menu option. Administrator can select standard, strict, custom and custom strict time zone handling. Standard handling does not differ from previous SquirrelMail versions and SquirrelMail uses GNU C geographical location based time zone names. Strict handling uses time zone codes with offset from GMT. Strict time zones should work on systems that don't support GNU C time zone naming. Custom and custom strict handling uses config/timezones.php file instead of include/timezones/standard.php. config/timezones.php file should store $aTimeZones array with different set of time zones. See default time zone set in include/timezones/standard.php.For example: GNU C time zone naming should be supported by many Unix OSes. It is recommended way of setting time zone, because it handles historical changes and daylight savings specific to selected geographical location. Strict time zones might provide inaccurate or outdated time zone settings. If modifications in TZ environment are visible in your webserver's logs (time offset is changed), make sure that you can reproduce such behavior in latest php version and report bug to php developers. Issue can be fixed by blocking use of time zone (php safe mode and TZ is not listed in safe_mode_allowed_env_vars setting or forced_prefs plugin) or by attaching special php script with putenv('TZ=some time zone') call in php auto_append_file setting (suggestion is not tested and you might have to fix all SquirrelMail exit calls). Please note, that use of auto_append_file provides only temporally workaround and does not fix your php setup. Script that runs as unprivileged user, should be unable to affect webserver's logging system.