X-Git-Url: https://vcs.fsf.org/?p=squirrelmail.git;a=blobdiff_plain;f=doc%2Fi18n.txt;h=92f1c4ba149fcf8d679591aa6cc57922a5b5d852;hp=293c6b5162b948b42f922e87f835c2abdb701226;hb=b4df37a525c34a317d5f6ff10baa518f75448703;hpb=7159c7e757f1f05124a2e1181b9b81d306d1aae8 diff --git a/doc/i18n.txt b/doc/i18n.txt index 293c6b51..92f1c4ba 100644 --- a/doc/i18n.txt +++ b/doc/i18n.txt @@ -1,4 +1,10 @@ -SquirrelMail internationalization + + ************************************* + * SquirrelMail internationalization * + ************************************* + +$Date$ +$Revision$ This document should explain how SquirrelMail internationalization works and provide information about some aspects of implementation. @@ -8,6 +14,9 @@ provide information about some aspects of implementation. 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 @@ -15,6 +24,7 @@ provide information about some aspects of implementation. 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 @@ -61,20 +71,65 @@ Valid language codes are: * 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 ------------------- -TODO: add explanation of $languages array keys +$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 provides way to change interface behaviour, when translation -requires special handling of some squirrelmail functions. Functions are enabled -by setting XTRA_CODE option in $languages array and providing appropriate -functions. First part of function name is word listed in -$languages['language_code']['XTRA_CODE'] setting. Second part is one of special -keywords. Possible values: +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 @@ -111,9 +166,193 @@ Used in functions/strings.php (sqWordWrap) -------------------------------- 4. Display of different charsets -------------------------------- -TODO: add explanation of decoding functions +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 -------------------- -TODO: add explanation about UTF7-IMAP and mbstring +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. +