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See Release Notes

  • Bug fixes for general core bugs in 4.0.x will end 8 May 2023 (12 months).
  • Bug fixes for security issues in 4.0.x will end 13 November 2023 (18 months).
  • PHP version: minimum PHP 7.3.0 Note: the minimum PHP version has increased since Moodle 3.10. PHP 7.4.x is also supported.

Differences Between: [Versions 310 and 400] [Versions 311 and 400] [Versions 39 and 400] [Versions 400 and 401] [Versions 400 and 402] [Versions 400 and 403]

   1  <?php
   2  // This file is part of Moodle - http://moodle.org/
   3  //
   4  // Moodle is free software: you can redistribute it and/or modify
   5  // it under the terms of the GNU General Public License as published by
   6  // the Free Software Foundation, either version 3 of the License, or
   7  // (at your option) any later version.
   8  //
   9  // Moodle is distributed in the hope that it will be useful,
  10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  // GNU General Public License for more details.
  13  //
  14  // You should have received a copy of the GNU General Public License
  15  // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16  
  17  /**
  18   * Standard string manager.
  19   *
  20   * @package    core
  21   * @copyright  2010 Petr Skoda {@link http://skodak.org}
  22   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  23   */
  24  
  25  defined('MOODLE_INTERNAL') || die();
  26  
  27  
  28  /**
  29   * Standard string_manager implementation
  30   *
  31   * Implements string_manager with getting and printing localised strings
  32   *
  33   * @package    core
  34   * @copyright  2010 Petr Skoda {@link http://skodak.org}
  35   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  36   */
  37  class core_string_manager_standard implements core_string_manager {
  38      /** @var string location of all packs except 'en' */
  39      protected $otherroot;
  40      /** @var string location of all lang pack local modifications */
  41      protected $localroot;
  42      /** @var cache lang string cache - it will be optimised more later */
  43      protected $cache;
  44      /** @var int get_string() counter */
  45      protected $countgetstring = 0;
  46      /** @var bool use disk cache */
  47      protected $translist;
  48      /** @var array language aliases to use in the language selector */
  49      protected $transaliases = [];
  50      /** @var cache stores list of available translations */
  51      protected $menucache;
  52      /** @var array list of cached deprecated strings */
  53      protected $cacheddeprecated;
  54  
  55      /**
  56       * Create new instance of string manager
  57       *
  58       * @param string $otherroot location of downloaded lang packs - usually $CFG->dataroot/lang
  59       * @param string $localroot usually the same as $otherroot
  60       * @param array $translist limit list of visible translations
  61       * @param array $transaliases aliases to use for the languages in the language selector
  62       */
  63      public function __construct($otherroot, $localroot, $translist, $transaliases = []) {
  64          $this->otherroot    = $otherroot;
  65          $this->localroot    = $localroot;
  66          if ($translist) {
  67              $this->translist = array_combine($translist, $translist);
  68              $this->transaliases = $transaliases;
  69          } else {
  70              $this->translist = array();
  71          }
  72  
  73          if ($this->get_revision() > 0) {
  74              // We can use a proper cache, establish the cache using the 'String cache' definition.
  75              $this->cache = cache::make('core', 'string');
  76              $this->menucache = cache::make('core', 'langmenu');
  77          } else {
  78              // We only want a cache for the length of the request, create a static cache.
  79              $options = array(
  80                  'simplekeys' => true,
  81                  'simpledata' => true
  82              );
  83              $this->cache = cache::make_from_params(cache_store::MODE_REQUEST, 'core', 'string', array(), $options);
  84              $this->menucache = cache::make_from_params(cache_store::MODE_REQUEST, 'core', 'langmenu', array(), $options);
  85          }
  86      }
  87  
  88      /**
  89       * Returns list of all explicit parent languages for the given language.
  90       *
  91       * English (en) is considered as the top implicit parent of all language packs
  92       * and is not included in the returned list. The language itself is appended to the
  93       * end of the list. The method is aware of circular dependency risk.
  94       *
  95       * @see self::populate_parent_languages()
  96       * @param string $lang the code of the language
  97       * @return array all explicit parent languages with the lang itself appended
  98       */
  99      public function get_language_dependencies($lang) {
 100          return $this->populate_parent_languages($lang);
 101      }
 102  
 103      /**
 104       * Load all strings for one component
 105       *
 106       * @param string $component The module the string is associated with
 107       * @param string $lang
 108       * @param bool $disablecache Do not use caches, force fetching the strings from sources
 109       * @param bool $disablelocal Do not use customized strings in xx_local language packs
 110       * @return array of all string for given component and lang
 111       */
 112      public function load_component_strings($component, $lang, $disablecache = false, $disablelocal = false) {
 113          global $CFG;
 114  
 115          list($plugintype, $pluginname) = core_component::normalize_component($component);
 116          if ($plugintype === 'core' and is_null($pluginname)) {
 117              $component = 'core';
 118          } else {
 119              $component = $plugintype . '_' . $pluginname;
 120          }
 121  
 122          $cachekey = $lang.'_'.$component.'_'.$this->get_key_suffix();
 123  
 124          $cachedstring = $this->cache->get($cachekey);
 125          if (!$disablecache and !$disablelocal) {
 126              if ($cachedstring !== false) {
 127                  return $cachedstring;
 128              }
 129          }
 130  
 131          // No cache found - let us merge all possible sources of the strings.
 132          if ($plugintype === 'core') {
 133              $file = $pluginname;
 134              if ($file === null) {
 135                  $file = 'moodle';
 136              }
 137              $string = array();
 138              // First load english pack.
 139              if (!file_exists("$CFG->dirroot/lang/en/$file.php")) {
 140                  return array();
 141              }
 142              include("$CFG->dirroot/lang/en/$file.php");
 143              $enstring = $string;
 144  
 145              // And then corresponding local if present and allowed.
 146              if (!$disablelocal and file_exists("$this->localroot/en_local/$file.php")) {
 147                  include("$this->localroot/en_local/$file.php");
 148              }
 149              // Now loop through all langs in correct order.
 150              $deps = $this->get_language_dependencies($lang);
 151              foreach ($deps as $dep) {
 152                  // The main lang string location.
 153                  if (file_exists("$this->otherroot/$dep/$file.php")) {
 154                      include("$this->otherroot/$dep/$file.php");
 155                  }
 156                  if (!$disablelocal and file_exists("$this->localroot/{$dep}_local/$file.php")) {
 157                      include("$this->localroot/{$dep}_local/$file.php");
 158                  }
 159              }
 160  
 161          } else {
 162              if (!$location = core_component::get_plugin_directory($plugintype, $pluginname) or !is_dir($location)) {
 163                  return array();
 164              }
 165              if ($plugintype === 'mod') {
 166                  // Bloody mod hack.
 167                  $file = $pluginname;
 168              } else {
 169                  $file = $plugintype . '_' . $pluginname;
 170              }
 171              $string = array();
 172              // First load English pack.
 173              if (!file_exists("$location/lang/en/$file.php")) {
 174                  // English pack does not exist, so do not try to load anything else.
 175                  return array();
 176              }
 177              include("$location/lang/en/$file.php");
 178              $enstring = $string;
 179              // And then corresponding local english if present.
 180              if (!$disablelocal and file_exists("$this->localroot/en_local/$file.php")) {
 181                  include("$this->localroot/en_local/$file.php");
 182              }
 183  
 184              // Now loop through all langs in correct order.
 185              $deps = $this->get_language_dependencies($lang);
 186              foreach ($deps as $dep) {
 187                  // Legacy location - used by contrib only.
 188                  if (file_exists("$location/lang/$dep/$file.php")) {
 189                      include("$location/lang/$dep/$file.php");
 190                  }
 191                  // The main lang string location.
 192                  if (file_exists("$this->otherroot/$dep/$file.php")) {
 193                      include("$this->otherroot/$dep/$file.php");
 194                  }
 195                  // Local customisations.
 196                  if (!$disablelocal and file_exists("$this->localroot/{$dep}_local/$file.php")) {
 197                      include("$this->localroot/{$dep}_local/$file.php");
 198                  }
 199              }
 200          }
 201  
 202          // We do not want any extra strings from other languages - everything must be in en lang pack.
 203          $string = array_intersect_key($string, $enstring);
 204  
 205          if (!$disablelocal) {
 206              // Now we have a list of strings from all possible sources,
 207              // cache it in MUC cache if not already there.
 208              if ($cachedstring === false) {
 209                  $this->cache->set($cachekey, $string);
 210              }
 211          }
 212          return $string;
 213      }
 214  
 215      /**
 216       * Parses all deprecated.txt in all plugins lang locations and returns the list of deprecated strings.
 217       *
 218       * Static variable is used for caching, this function is only called in dev environment.
 219       *
 220       * @return array of deprecated strings in the same format they appear in deprecated.txt files: "identifier,component"
 221       *     where component is a normalised component (i.e. "core_moodle", "mod_assign", etc.)
 222       */
 223      protected function load_deprecated_strings() {
 224          global $CFG;
 225  
 226          if ($this->cacheddeprecated !== null) {
 227              return $this->cacheddeprecated;
 228          }
 229  
 230          $this->cacheddeprecated = array();
 231          $content = '';
 232          $filename = $CFG->dirroot . '/lang/en/deprecated.txt';
 233          if (file_exists($filename)) {
 234              $content .= file_get_contents($filename);
 235          }
 236          foreach (core_component::get_plugin_types() as $plugintype => $plugintypedir) {
 237              foreach (core_component::get_plugin_list($plugintype) as $pluginname => $plugindir) {
 238                  $filename = $plugindir.'/lang/en/deprecated.txt';
 239                  if (file_exists($filename)) {
 240                      $content .= "\n". file_get_contents($filename);
 241                  }
 242              }
 243          }
 244  
 245          $strings = preg_split('/\s*\n\s*/', $content, -1, PREG_SPLIT_NO_EMPTY);
 246          $this->cacheddeprecated = array_flip($strings);
 247  
 248          return $this->cacheddeprecated;
 249      }
 250  
 251      /**
 252       * Has string been deprecated?
 253       *
 254       * Usually checked only inside get_string() to display debug warnings.
 255       *
 256       * @param string $identifier The identifier of the string to search for
 257       * @param string $component The module the string is associated with
 258       * @return bool true if deprecated
 259       */
 260      public function string_deprecated($identifier, $component) {
 261          $deprecated = $this->load_deprecated_strings();
 262          list($plugintype, $pluginname) = core_component::normalize_component($component);
 263          $normcomponent = $pluginname ? ($plugintype . '_' . $pluginname) : $plugintype;
 264          return isset($deprecated[$identifier . ',' . $normcomponent]);
 265      }
 266  
 267      /**
 268       * Does the string actually exist?
 269       *
 270       * get_string() is throwing debug warnings, sometimes we do not want them
 271       * or we want to display better explanation of the problem.
 272       * Note: Use with care!
 273       *
 274       * @param string $identifier The identifier of the string to search for
 275       * @param string $component The module the string is associated with
 276       * @return boot true if exists
 277       */
 278      public function string_exists($identifier, $component) {
 279          $lang = current_language();
 280          $string = $this->load_component_strings($component, $lang);
 281          return isset($string[$identifier]);
 282      }
 283  
 284      /**
 285       * Get String returns a requested string
 286       *
 287       * @param string $identifier The identifier of the string to search for
 288       * @param string $component The module the string is associated with
 289       * @param string|object|array $a An object, string or number that can be used
 290       *      within translation strings
 291       * @param string $lang moodle translation language, null means use current
 292       * @return string The String !
 293       */
 294      public function get_string($identifier, $component = '', $a = null, $lang = null) {
 295          global $CFG;
 296  
 297          $this->countgetstring++;
 298          // There are very many uses of these time formatting strings without the 'langconfig' component,
 299          // it would not be reasonable to expect that all of them would be converted during 2.0 migration.
 300          static $langconfigstrs = array(
 301              'strftimedate' => 1,
 302              'strftimedatefullshort' => 1,
 303              'strftimedateshort' => 1,
 304              'strftimedatetime' => 1,
 305              'strftimedatetimeaccurate' => 1,
 306              'strftimedatetimeshort' => 1,
 307              'strftimedatetimeshortaccurate' => 1,
 308              'strftimedaydate' => 1,
 309              'strftimedaydatetime' => 1,
 310              'strftimedayshort' => 1,
 311              'strftimedaytime' => 1,
 312              'strftimemonth' => 1,
 313              'strftimemonthyear' => 1,
 314              'strftimerecent' => 1,
 315              'strftimerecentfull' => 1,
 316              'strftimetime' => 1);
 317  
 318          if (empty($component)) {
 319              if (isset($langconfigstrs[$identifier])) {
 320                  $component = 'langconfig';
 321              } else {
 322                  $component = 'moodle';
 323              }
 324          }
 325  
 326          if ($lang === null) {
 327              $lang = current_language();
 328          }
 329  
 330          $string = $this->load_component_strings($component, $lang);
 331  
 332          if (!isset($string[$identifier])) {
 333              if ($component === 'pix' or $component === 'core_pix') {
 334                  // This component contains only alt tags for emoticons, not all of them are supposed to be defined.
 335                  return '';
 336              }
 337              if ($identifier === 'parentlanguage' and ($component === 'langconfig' or $component === 'core_langconfig')) {
 338                  // Identifier parentlanguage is a special string, undefined means use English if not defined.
 339                  return 'en';
 340              }
 341              // Do not rebuild caches here!
 342              // Devs need to learn to purge all caches after any change or disable $CFG->langstringcache.
 343              if (!isset($string[$identifier])) {
 344                  // The string is still missing - should be fixed by developer.
 345                  if ($CFG->debugdeveloper) {
 346                      list($plugintype, $pluginname) = core_component::normalize_component($component);
 347                      if ($plugintype === 'core') {
 348                          $file = "lang/en/{$component}.php";
 349                      } else if ($plugintype == 'mod') {
 350                          $file = "mod/{$pluginname}/lang/en/{$pluginname}.php";
 351                      } else {
 352                          $path = core_component::get_plugin_directory($plugintype, $pluginname);
 353                          $file = "{$path}/lang/en/{$plugintype}_{$pluginname}.php";
 354                      }
 355                      debugging("Invalid get_string() identifier: '{$identifier}' or component '{$component}'. " .
 356                      "Perhaps you are missing \$string['{$identifier}'] = ''; in {$file}?", DEBUG_DEVELOPER);
 357                  }
 358                  return "[[$identifier]]";
 359              }
 360          }
 361  
 362          $string = $string[$identifier];
 363  
 364          if ($a !== null) {
 365              // Process array's and objects (except lang_strings).
 366              if (is_array($a) or (is_object($a) && !($a instanceof lang_string))) {
 367                  $a = (array)$a;
 368                  $search = array();
 369                  $replace = array();
 370                  foreach ($a as $key => $value) {
 371                      if (is_int($key)) {
 372                          // We do not support numeric keys - sorry!
 373                          continue;
 374                      }
 375                      if (is_array($value) or (is_object($value) && !($value instanceof lang_string))) {
 376                          // We support just string or lang_string as value.
 377                          continue;
 378                      }
 379                      $search[]  = '{$a->'.$key.'}';
 380                      $replace[] = (string)$value;
 381                  }
 382                  if ($search) {
 383                      $string = str_replace($search, $replace, $string);
 384                  }
 385              } else {
 386                  $string = str_replace('{$a}', (string)$a, $string);
 387              }
 388          }
 389  
 390          if ($CFG->debugdeveloper) {
 391              // Display a debugging message if sting exists but was deprecated.
 392              if ($this->string_deprecated($identifier, $component)) {
 393                  list($plugintype, $pluginname) = core_component::normalize_component($component);
 394                  $normcomponent = $pluginname ? ($plugintype . '_' . $pluginname) : $plugintype;
 395                  debugging("String [{$identifier},{$normcomponent}] is deprecated. ".
 396                      'Either you should no longer be using that string, or the string has been incorrectly deprecated, in which case you should report this as a bug. '.
 397                      'Please refer to https://docs.moodle.org/dev/String_deprecation', DEBUG_DEVELOPER);
 398              }
 399          }
 400  
 401          return $string;
 402      }
 403  
 404      /**
 405       * Returns information about the core_string_manager performance.
 406       *
 407       * @return array
 408       */
 409      public function get_performance_summary() {
 410          return array(array(
 411              'langcountgetstring' => $this->countgetstring,
 412          ), array(
 413              'langcountgetstring' => 'get_string calls',
 414          ));
 415      }
 416  
 417      /**
 418       * Returns a localised list of all country names, sorted by localised name.
 419       *
 420       * @param bool $returnall return all or just enabled
 421       * @param string $lang moodle translation language, null means use current
 422       * @return array two-letter country code => translated name.
 423       */
 424      public function get_list_of_countries($returnall = false, $lang = null) {
 425          global $CFG;
 426  
 427          if ($lang === null) {
 428              $lang = current_language();
 429          }
 430  
 431          $countries = $this->load_component_strings('core_countries', $lang);
 432          core_collator::asort($countries);
 433  
 434          if (!$returnall and !empty($CFG->allcountrycodes)) {
 435              $enabled = explode(',', $CFG->allcountrycodes);
 436              $return = array();
 437              foreach ($enabled as $c) {
 438                  if (isset($countries[$c])) {
 439                      $return[$c] = $countries[$c];
 440                  }
 441              }
 442  
 443              if (!empty($return)) {
 444                  return $return;
 445              }
 446          }
 447  
 448          return $countries;
 449      }
 450  
 451      /**
 452       * Returns a localised list of languages, sorted by code keys.
 453       *
 454       * @param string $lang moodle translation language, null means use current
 455       * @param string $standard language list standard
 456       *    - iso6392: three-letter language code (ISO 639-2/T) => translated name
 457       *    - iso6391: two-letter language code (ISO 639-1) => translated name
 458       * @return array language code => translated name
 459       */
 460      public function get_list_of_languages($lang = null, $standard = 'iso6391') {
 461          if ($lang === null) {
 462              $lang = current_language();
 463          }
 464  
 465          if ($standard === 'iso6392') {
 466              $langs = $this->load_component_strings('core_iso6392', $lang);
 467              ksort($langs);
 468              return $langs;
 469  
 470          } else if ($standard === 'iso6391') {
 471              $langs2 = $this->load_component_strings('core_iso6392', $lang);
 472              static $mapping = array('aar' => 'aa', 'abk' => 'ab', 'afr' => 'af', 'aka' => 'ak', 'sqi' => 'sq', 'amh' => 'am', 'ara' => 'ar', 'arg' => 'an', 'hye' => 'hy',
 473                  'asm' => 'as', 'ava' => 'av', 'ave' => 'ae', 'aym' => 'ay', 'aze' => 'az', 'bak' => 'ba', 'bam' => 'bm', 'eus' => 'eu', 'bel' => 'be', 'ben' => 'bn', 'bih' => 'bh',
 474                  'bis' => 'bi', 'bos' => 'bs', 'bre' => 'br', 'bul' => 'bg', 'mya' => 'my', 'cat' => 'ca', 'cha' => 'ch', 'che' => 'ce', 'zho' => 'zh', 'chu' => 'cu', 'chv' => 'cv',
 475                  'cor' => 'kw', 'cos' => 'co', 'cre' => 'cr', 'ces' => 'cs', 'dan' => 'da', 'div' => 'dv', 'nld' => 'nl', 'dzo' => 'dz', 'eng' => 'en', 'epo' => 'eo', 'est' => 'et',
 476                  'ewe' => 'ee', 'fao' => 'fo', 'fij' => 'fj', 'fin' => 'fi', 'fra' => 'fr', 'fry' => 'fy', 'ful' => 'ff', 'kat' => 'ka', 'deu' => 'de', 'gla' => 'gd', 'gle' => 'ga',
 477                  'glg' => 'gl', 'glv' => 'gv', 'ell' => 'el', 'grn' => 'gn', 'guj' => 'gu', 'hat' => 'ht', 'hau' => 'ha', 'heb' => 'he', 'her' => 'hz', 'hin' => 'hi', 'hmo' => 'ho',
 478                  'hrv' => 'hr', 'hun' => 'hu', 'ibo' => 'ig', 'isl' => 'is', 'ido' => 'io', 'iii' => 'ii', 'iku' => 'iu', 'ile' => 'ie', 'ina' => 'ia', 'ind' => 'id', 'ipk' => 'ik',
 479                  'ita' => 'it', 'jav' => 'jv', 'jpn' => 'ja', 'kal' => 'kl', 'kan' => 'kn', 'kas' => 'ks', 'kau' => 'kr', 'kaz' => 'kk', 'khm' => 'km', 'kik' => 'ki', 'kin' => 'rw',
 480                  'kir' => 'ky', 'kom' => 'kv', 'kon' => 'kg', 'kor' => 'ko', 'kua' => 'kj', 'kur' => 'ku', 'lao' => 'lo', 'lat' => 'la', 'lav' => 'lv', 'lim' => 'li', 'lin' => 'ln',
 481                  'lit' => 'lt', 'ltz' => 'lb', 'lub' => 'lu', 'lug' => 'lg', 'mkd' => 'mk', 'mah' => 'mh', 'mal' => 'ml', 'mri' => 'mi', 'mar' => 'mr', 'msa' => 'ms', 'mlg' => 'mg',
 482                  'mlt' => 'mt', 'mon' => 'mn', 'nau' => 'na', 'nav' => 'nv', 'nbl' => 'nr', 'nde' => 'nd', 'ndo' => 'ng', 'nep' => 'ne', 'nno' => 'nn', 'nob' => 'nb', 'nor' => 'no',
 483                  'nya' => 'ny', 'oci' => 'oc', 'oji' => 'oj', 'ori' => 'or', 'orm' => 'om', 'oss' => 'os', 'pan' => 'pa', 'fas' => 'fa', 'pli' => 'pi', 'pol' => 'pl', 'por' => 'pt',
 484                  'pus' => 'ps', 'que' => 'qu', 'roh' => 'rm', 'ron' => 'ro', 'run' => 'rn', 'rus' => 'ru', 'sag' => 'sg', 'san' => 'sa', 'sin' => 'si', 'slk' => 'sk', 'slv' => 'sl',
 485                  'sme' => 'se', 'smo' => 'sm', 'sna' => 'sn', 'snd' => 'sd', 'som' => 'so', 'sot' => 'st', 'spa' => 'es', 'srd' => 'sc', 'srp' => 'sr', 'ssw' => 'ss', 'sun' => 'su',
 486                  'swa' => 'sw', 'swe' => 'sv', 'tah' => 'ty', 'tam' => 'ta', 'tat' => 'tt', 'tel' => 'te', 'tgk' => 'tg', 'tgl' => 'tl', 'tha' => 'th', 'bod' => 'bo', 'tir' => 'ti',
 487                  'ton' => 'to', 'tsn' => 'tn', 'tso' => 'ts', 'tuk' => 'tk', 'tur' => 'tr', 'twi' => 'tw', 'uig' => 'ug', 'ukr' => 'uk', 'urd' => 'ur', 'uzb' => 'uz', 'ven' => 've',
 488                  'vie' => 'vi', 'vol' => 'vo', 'cym' => 'cy', 'wln' => 'wa', 'wol' => 'wo', 'xho' => 'xh', 'yid' => 'yi', 'yor' => 'yo', 'zha' => 'za', 'zul' => 'zu');
 489              $langs1 = array();
 490              foreach ($mapping as $c2 => $c1) {
 491                  $langs1[$c1] = $langs2[$c2];
 492              }
 493              ksort($langs1);
 494              return $langs1;
 495  
 496          } else {
 497              debugging('Unsupported $standard parameter in get_list_of_languages() method: '.$standard);
 498          }
 499  
 500          return array();
 501      }
 502  
 503      /**
 504       * Checks if the translation exists for the language
 505       *
 506       * @param string $lang moodle translation language code
 507       * @param bool $includeall include also disabled translations
 508       * @return bool true if exists
 509       */
 510      public function translation_exists($lang, $includeall = true) {
 511          $translations = $this->get_list_of_translations($includeall);
 512          return isset($translations[$lang]);
 513      }
 514  
 515      /**
 516       * Returns localised list of installed translations
 517       *
 518       * @param bool $returnall return all or just enabled
 519       * @return array moodle translation code => localised translation name
 520       */
 521      public function get_list_of_translations($returnall = false) {
 522          global $CFG;
 523  
 524          $languages = array();
 525  
 526          $cachekey = 'list_'.$this->get_key_suffix();
 527          $cachedlist = $this->menucache->get($cachekey);
 528          if ($cachedlist !== false) {
 529              // The cache content is invalid.
 530              if ($returnall or empty($this->translist)) {
 531                  return $cachedlist;
 532              }
 533              // Return only enabled translations.
 534              foreach ($cachedlist as $langcode => $langname) {
 535                  if (array_key_exists($langcode, $this->translist)) {
 536                      $languages[$langcode] = !empty($this->transaliases[$langcode]) ? $this->transaliases[$langcode] : $langname;
 537                  }
 538              }
 539  
 540              // If there are no valid enabled translations, then return all languages.
 541              if (!empty($languages)) {
 542                  return $languages;
 543              } else {
 544                  return $cachedlist;
 545              }
 546          }
 547  
 548          // Get all languages available in system.
 549          $langdirs = get_list_of_plugins('', 'en', $this->otherroot);
 550          $langdirs["$CFG->dirroot/lang/en"] = 'en';
 551  
 552          // We use left to right mark to demark the shortcodes contained in LTR brackets, but we need to do
 553          // this hacky thing to have the utf8 char until we go php7 minimum and can simply put \u200E in
 554          // a double quoted string.
 555          $lrm = json_decode('"\u200E"');
 556  
 557          // Loop through all langs and get info.
 558          foreach ($langdirs as $lang) {
 559              if (strrpos($lang, '_local') !== false) {
 560                  // Just a local tweak of some other lang pack.
 561                  continue;
 562              }
 563              if (strrpos($lang, '_utf8') !== false) {
 564                  // Legacy 1.x lang pack.
 565                  continue;
 566              }
 567              if ($lang !== clean_param($lang, PARAM_SAFEDIR)) {
 568                  // Invalid lang pack name!
 569                  continue;
 570              }
 571              $string = $this->load_component_strings('langconfig', $lang);
 572              if (!empty($string['thislanguage'])) {
 573                  $languages[$lang] = $string['thislanguage'].' '.$lrm.'('. $lang .')'.$lrm;
 574              }
 575          }
 576  
 577          core_collator::asort($languages);
 578  
 579          // Cache the list so that it can be used next time.
 580          $this->menucache->set($cachekey, $languages);
 581  
 582          if ($returnall or empty($this->translist)) {
 583              return $languages;
 584          }
 585  
 586          $cachedlist = $languages;
 587  
 588          // Return only enabled translations.
 589          $languages = array();
 590          foreach ($cachedlist as $langcode => $langname) {
 591              if (isset($this->translist[$langcode])) {
 592                  $languages[$langcode] = !empty($this->transaliases[$langcode]) ? $this->transaliases[$langcode] : $langname;
 593              }
 594          }
 595  
 596          // If there are no valid enabled translations, then return all languages.
 597          if (!empty($languages)) {
 598              return $languages;
 599          } else {
 600              return $cachedlist;
 601          }
 602      }
 603  
 604      /**
 605       * Returns localised list of currencies.
 606       *
 607       * @param string $lang moodle translation language, null means use current
 608       * @return array currency code => localised currency name
 609       */
 610      public function get_list_of_currencies($lang = null) {
 611          if ($lang === null) {
 612              $lang = current_language();
 613          }
 614  
 615          $currencies = $this->load_component_strings('core_currencies', $lang);
 616          asort($currencies);
 617  
 618          return $currencies;
 619      }
 620  
 621      /**
 622       * Clears both in-memory and on-disk caches
 623       * @param bool $phpunitreset true means called from our PHPUnit integration test reset
 624       */
 625      public function reset_caches($phpunitreset = false) {
 626          // Clear the on-disk disk with aggregated string files.
 627          $this->cache->purge();
 628          $this->menucache->purge();
 629  
 630          if (!$phpunitreset) {
 631              // Increment the revision counter.
 632              $langrev = get_config('core', 'langrev');
 633              $next = time();
 634              if ($langrev !== false and $next <= $langrev and $langrev - $next < 60*60) {
 635                  // This resolves problems when reset is requested repeatedly within 1s,
 636                  // the < 1h condition prevents accidental switching to future dates
 637                  // because we might not recover from it.
 638                  $next = $langrev+1;
 639              }
 640              set_config('langrev', $next);
 641          }
 642  
 643          // Lang packs use PHP files in dataroot, it is better to invalidate opcode caches.
 644          if (function_exists('opcache_reset')) {
 645              opcache_reset();
 646          }
 647      }
 648  
 649      /**
 650       * Returns cache key suffix, this enables us to store string + lang menu
 651       * caches in local caches on cluster nodes. We can not use prefix because
 652       * it would cause problems when creating subdirs in cache file store.
 653       * @return string
 654       */
 655      protected function get_key_suffix() {
 656          $rev = $this->get_revision();
 657          if ($rev < 0) {
 658              // Simple keys do not like minus char.
 659              $rev = 0;
 660          }
 661  
 662          return $rev;
 663      }
 664  
 665      /**
 666       * Returns string revision counter, this is incremented after any string cache reset.
 667       * @return int lang string revision counter, -1 if unknown
 668       */
 669      public function get_revision() {
 670          global $CFG;
 671          if (empty($CFG->langstringcache)) {
 672              return -1;
 673          }
 674          if (isset($CFG->langrev)) {
 675              return (int)$CFG->langrev;
 676          } else {
 677              return -1;
 678          }
 679      }
 680  
 681      /**
 682       * Helper method that recursively loads all parents of the given language.
 683       *
 684       * @see self::get_language_dependencies()
 685       * @param string $lang language code
 686       * @param array $stack list of parent languages already populated in previous recursive calls
 687       * @return array list of all parents of the given language with the $lang itself added as the last element
 688       */
 689      protected function populate_parent_languages($lang, array $stack = array()) {
 690  
 691          // English does not have a parent language.
 692          if ($lang === 'en') {
 693              return $stack;
 694          }
 695  
 696          // Prevent circular dependency (and thence the infinitive recursion loop).
 697          if (in_array($lang, $stack)) {
 698              return $stack;
 699          }
 700  
 701          // Load language configuration and look for the explicit parent language.
 702          if (!file_exists("$this->otherroot/$lang/langconfig.php")) {
 703              return $stack;
 704          }
 705          $string = array();
 706          include("$this->otherroot/$lang/langconfig.php");
 707  
 708          if (empty($string['parentlanguage']) or $string['parentlanguage'] === 'en') {
 709              return array_merge(array($lang), $stack);
 710  
 711          }
 712  
 713          $parentlang = $string['parentlanguage'];
 714          return $this->populate_parent_languages($parentlang, array_merge(array($lang), $stack));
 715      }
 716  }