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Diffstat (limited to 'include/php-gettext/gettext.php')
-rw-r--r-- | include/php-gettext/gettext.php | 408 |
1 files changed, 408 insertions, 0 deletions
diff --git a/include/php-gettext/gettext.php b/include/php-gettext/gettext.php new file mode 100644 index 000000000..f11da2e27 --- /dev/null +++ b/include/php-gettext/gettext.php @@ -0,0 +1,408 @@ +<?php +/* + Copyright (c) 2003, 2009 Danilo Segan <danilo@kvota.net>. + Copyright (c) 2005 Nico Kaiser <nico@siriux.net> + + This file is part of PHP-gettext. + + PHP-gettext is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + PHP-gettext 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with PHP-gettext; if not, write to the Free Software + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + +*/ + +/** + * Provides a simple gettext replacement that works independently from + * the system's gettext abilities. + * It can read MO files and use them for translating strings. + * The files are passed to gettext_reader as a Stream (see streams.php) + * + * This version has the ability to cache all strings and translations to + * speed up the string lookup. + * While the cache is enabled by default, it can be switched off with the + * second parameter in the constructor (e.g. whenusing very large MO files + * that you don't want to keep in memory) + */ +class gettext_reader { + //public: + var $error = 0; // public variable that holds error code (0 if no error) + + //private: + var $BYTEORDER = 0; // 0: low endian, 1: big endian + var $STREAM = NULL; + var $short_circuit = false; + var $enable_cache = false; + var $originals = NULL; // offset of original table + var $translations = NULL; // offset of translation table + var $pluralheader = NULL; // cache header field for plural forms + var $total = 0; // total string count + var $table_originals = NULL; // table for original strings (offsets) + var $table_translations = NULL; // table for translated strings (offsets) + var $cache_translations = NULL; // original -> translation mapping + + + /* Methods */ + + + /** + * Reads a 32bit Integer from the Stream + * + * @access private + * @return Integer from the Stream + */ + function readint() { + if ($this->BYTEORDER == 0) { + // low endian + $input=unpack('V', $this->STREAM->read(4)); + return array_shift($input); + } else { + // big endian + $input=unpack('N', $this->STREAM->read(4)); + return array_shift($input); + } + } + + function read($bytes) { + return $this->STREAM->read($bytes); + } + + /** + * Reads an array of Integers from the Stream + * + * @param int count How many elements should be read + * @return Array of Integers + */ + function readintarray($count) { + if ($this->BYTEORDER == 0) { + // low endian + return unpack('V'.$count, $this->STREAM->read(4 * $count)); + } else { + // big endian + return unpack('N'.$count, $this->STREAM->read(4 * $count)); + } + } + + /** + * Constructor + * + * @param object Reader the StreamReader object + * @param boolean enable_cache Enable or disable caching of strings (default on) + */ + function gettext_reader($Reader, $enable_cache = true) { + // If there isn't a StreamReader, turn on short circuit mode. + if (! $Reader || isset($Reader->error) ) { + $this->short_circuit = true; + return; + } + + // Caching can be turned off + $this->enable_cache = $enable_cache; + + $MAGIC1 = "\x95\x04\x12\xde"; + $MAGIC2 = "\xde\x12\x04\x95"; + + $this->STREAM = $Reader; + $magic = $this->read(4); + if ($magic == $MAGIC1) { + $this->BYTEORDER = 1; + } elseif ($magic == $MAGIC2) { + $this->BYTEORDER = 0; + } else { + $this->error = 1; // not MO file + return false; + } + + // FIXME: Do we care about revision? We should. + $revision = $this->readint(); + + $this->total = $this->readint(); + $this->originals = $this->readint(); + $this->translations = $this->readint(); + } + + /** + * Loads the translation tables from the MO file into the cache + * If caching is enabled, also loads all strings into a cache + * to speed up translation lookups + * + * @access private + */ + function load_tables() { + if (is_array($this->cache_translations) && + is_array($this->table_originals) && + is_array($this->table_translations)) + return; + + /* get original and translations tables */ + $this->STREAM->seekto($this->originals); + $this->table_originals = $this->readintarray($this->total * 2); + $this->STREAM->seekto($this->translations); + $this->table_translations = $this->readintarray($this->total * 2); + + if ($this->enable_cache) { + $this->cache_translations = array (); + /* read all strings in the cache */ + for ($i = 0; $i < $this->total; $i++) { + $this->STREAM->seekto($this->table_originals[$i * 2 + 2]); + $original = $this->STREAM->read($this->table_originals[$i * 2 + 1]); + $this->STREAM->seekto($this->table_translations[$i * 2 + 2]); + $translation = $this->STREAM->read($this->table_translations[$i * 2 + 1]); + $this->cache_translations[$original] = $translation; + } + } + } + + /** + * Returns a string from the "originals" table + * + * @access private + * @param int num Offset number of original string + * @return string Requested string if found, otherwise '' + */ + function get_original_string($num) { + $length = $this->table_originals[$num * 2 + 1]; + $offset = $this->table_originals[$num * 2 + 2]; + if (! $length) + return ''; + $this->STREAM->seekto($offset); + $data = $this->STREAM->read($length); + return (string)$data; + } + + /** + * Returns a string from the "translations" table + * + * @access private + * @param int num Offset number of original string + * @return string Requested string if found, otherwise '' + */ + function get_translation_string($num) { + $length = $this->table_translations[$num * 2 + 1]; + $offset = $this->table_translations[$num * 2 + 2]; + if (! $length) + return ''; + $this->STREAM->seekto($offset); + $data = $this->STREAM->read($length); + return (string)$data; + } + + /** + * Binary search for string + * + * @access private + * @param string string + * @param int start (internally used in recursive function) + * @param int end (internally used in recursive function) + * @return int string number (offset in originals table) + */ + function find_string($string, $start = -1, $end = -1) { + if (($start == -1) or ($end == -1)) { + // find_string is called with only one parameter, set start end end + $start = 0; + $end = $this->total; + } + if (abs($start - $end) <= 1) { + // We're done, now we either found the string, or it doesn't exist + $txt = $this->get_original_string($start); + if ($string == $txt) + return $start; + else + return -1; + } else if ($start > $end) { + // start > end -> turn around and start over + return $this->find_string($string, $end, $start); + } else { + // Divide table in two parts + $half = (int)(($start + $end) / 2); + $cmp = strcmp($string, $this->get_original_string($half)); + if ($cmp == 0) + // string is exactly in the middle => return it + return $half; + else if ($cmp < 0) + // The string is in the upper half + return $this->find_string($string, $start, $half); + else + // The string is in the lower half + return $this->find_string($string, $half, $end); + } + } + + /** + * Translates a string + * + * @access public + * @param string string to be translated + * @return string translated string (or original, if not found) + */ + function translate($string) { + if ($this->short_circuit) + return $string; + $this->load_tables(); + + if ($this->enable_cache) { + // Caching enabled, get translated string from cache + if (array_key_exists($string, $this->cache_translations)) + return $this->cache_translations[$string]; + else + return $string; + } else { + // Caching not enabled, try to find string + $num = $this->find_string($string); + if ($num == -1) + return $string; + else + return $this->get_translation_string($num); + } + } + + /** + * Sanitize plural form expression for use in PHP eval call. + * + * @access private + * @return string sanitized plural form expression + */ + function sanitize_plural_expression($expr) { + // Get rid of disallowed characters. + $expr = preg_replace('@[^a-zA-Z0-9_:;\(\)\?\|\&=!<>+*/\%-]@', '', $expr); + + // Add parenthesis for tertiary '?' operator. + $expr .= ';'; + $res = ''; + $p = 0; + for ($i = 0; $i < strlen($expr); $i++) { + $ch = $expr[$i]; + switch ($ch) { + case '?': + $res .= ' ? ('; + $p++; + break; + case ':': + $res .= ') : ('; + break; + case ';': + $res .= str_repeat( ')', $p) . ';'; + $p = 0; + break; + default: + $res .= $ch; + } + } + return $res; + } + + /** + * Parse full PO header and extract only plural forms line. + * + * @access private + * @return string verbatim plural form header field + */ + function extract_plural_forms_header_from_po_header($header) { + if (preg_match("/(^|\n)plural-forms: ([^\n]*)\n/i", $header, $regs)) + $expr = $regs[2]; + else + $expr = "nplurals=2; plural=n == 1 ? 0 : 1;"; + return $expr; + } + + /** + * Get possible plural forms from MO header + * + * @access private + * @return string plural form header + */ + function get_plural_forms() { + // lets assume message number 0 is header + // this is true, right? + $this->load_tables(); + + // cache header field for plural forms + if (! is_string($this->pluralheader)) { + if ($this->enable_cache) { + $header = $this->cache_translations[""]; + } else { + $header = $this->get_translation_string(0); + } + $expr = $this->extract_plural_forms_header_from_po_header($header); + $this->pluralheader = $this->sanitize_plural_expression($expr); + } + return $this->pluralheader; + } + + /** + * Detects which plural form to take + * + * @access private + * @param n count + * @return int array index of the right plural form + */ + function select_string($n) { + $string = $this->get_plural_forms(); + $string = str_replace('nplurals',"\$total",$string); + $string = str_replace("n",$n,$string); + $string = str_replace('plural',"\$plural",$string); + + $total = 0; + $plural = 0; + + eval("$string"); + if ($plural >= $total) $plural = $total - 1; + return $plural; + } + + /** + * Plural version of gettext + * + * @access public + * @param string single + * @param string plural + * @param string number + * @return translated plural form + */ + function ngettext($single, $plural, $number) { + if ($this->short_circuit) { + if ($number != 1) + return $plural; + else + return $single; + } + + // find out the appropriate form + $select = $this->select_string($number); + + // this should contains all strings separated by NULLs + $key = $single.chr(0).$plural; + + + if ($this->enable_cache) { + if (! array_key_exists($key, $this->cache_translations)) { + return ($number != 1) ? $plural : $single; + } else { + $result = $this->cache_translations[$key]; + $list = explode(chr(0), $result); + return $list[$select]; + } + } else { + $num = $this->find_string($key); + if ($num == -1) { + return ($number != 1) ? $plural : $single; + } else { + $result = $this->get_translation_string($num); + $list = explode(chr(0), $result); + return $list[$select]; + } + } + } + +} + +?> |