-
- *************************************
- * 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 and defines translations
-that are enabled in SquirrelMail.
-
-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 $languages array and including appropriate
-functions in functions/i18n.php. First part of function name is word listed in
-$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 use default webserver's time zone.
-
-List of available time zones is stored in locale/timezones.cfg. Current list
-of time zones uses some time zone names that depend on webserver's system
-libraries. These names are not compatible with Windows operating system.
-
-TODO: move time zone information to php array in order to be able to translate
-it and make sure that time zone names are compatible with Windows operating
-system. Or at least provide 'default' and 'strict' time zone options in
-SquirrelMail configuration. Maybe even provide 'custom' time zone list
-options.
-
-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.
-
+See: http://www.squirrelmail.org/docs/devel/devel-3.html
projects / squirrelmail.git / blobdiff