<?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 */ if (!is_array($this->table_originals)) { $this->STREAM->seekto($this->originals); $this->table_originals = $this->readintarray($this->total * 2); } if (!is_array($this->table_translations)) { $this->STREAM->seekto($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]; } } } function pgettext($context, $msgid) { $key = $context . chr(4) . $msgid; $ret = $this->translate($key); if (strpos($ret, "\004") !== false) { return $msgid; } else { return $ret; } } function npgettext($context, $singular, $plural, $number) { $key = $context . chr(4) . $singular; $ret = $this->ngettext($key, $plural, $number); if (strpos($ret, "\004") !== false) { return $singular; } else { return $ret; } } } ?>