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See Release Notes

  • Bug fixes for general core bugs in 4.2.x will end 22 April 2024 (12 months).
  • Bug fixes for security issues in 4.2.x will end 7 October 2024 (18 months).
  • PHP version: minimum PHP 8.0.0 Note: minimum PHP version has increased since Moodle 4.1. PHP 8.1.x is supported too.
<?php
// This file is part of Moodle - http://moodle.org/
//
// Moodle 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 3 of the License, or
// (at your option) any later version.
//
// Moodle 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 Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**
 * Environment class to aid with the detection and establishment of the working environment.
 *
 * @package    core
 * @copyright  2013 Sam Hemelryk
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

/**
 * The user agent class.
 *
 * It's important to note that we do not like browser sniffing and its use in core code is highly discouraged.
 * No new uses of this API will be integrated unless there is absolutely no alternative.
 *
 * This API supports the few browser checks we do have in core, all of which one day will hopefully be removed.
 * The API will remain to support any third party use out there, however at some point like all code it will be deprecated.
 *
 * Use sparingly and only with good cause!
 *
 * @package    core
 * @copyright  2013 Sam Hemelryk
 * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */
class core_useragent {

    /**
     * The default for devices, think of as a computer.
     */
    const DEVICETYPE_DEFAULT = 'default';
    /**
     * Legacy devices, or at least legacy browsers. These are older devices/browsers
     * that don't support standards.
     */
    const DEVICETYPE_LEGACY = 'legacy';
    /**
     * Mobile devices like your cell phone or hand held gaming device.
     */
    const DEVICETYPE_MOBILE = 'mobile';
    /**
     * Tables, larger than hand held, but still easily portable and smaller than a laptop.
     */
    const DEVICETYPE_TABLET = 'tablet';

    /**
     * An instance of this class.
     * @var core_useragent
     */
    protected static $instance = null;

    /**
     * The device types we track.
     * @var array
     */
    public static $devicetypes = array(
        self::DEVICETYPE_DEFAULT,
        self::DEVICETYPE_LEGACY,
        self::DEVICETYPE_MOBILE,
        self::DEVICETYPE_TABLET,
    );

    /**
     * The current requests user agent string if there was one.
     * @var string|bool|null Null until initialised, false if none available, or string when available.
     */
    protected $useragent = null;

    /**
     * The users device type, one of self::DEVICETYPE_*.
     * @var string null until initialised
     */
    protected $devicetype = null;

    /**
< * Custom device types entered into the admin interface. < * @var array < */ < protected $devicetypecustoms = array(); < < /**
* True if the user agent supports the display of svg images. False if not. * @var bool|null Null until initialised, then true or false. */ protected $supportssvg = null; /** * Get an instance of the user agent object. * * @param bool $reload If set to true the user agent will be reset and all ascertations remade. * @param string $forceuseragent The string to force as the user agent, don't use unless absolutely unavoidable. * @return core_useragent */ public static function instance($reload = false, $forceuseragent = null) { if (!self::$instance || $reload) { self::$instance = new core_useragent($forceuseragent); } return self::$instance; } /** * Constructs a new user agent object. Publically you must use the instance method above. * * @param string|null $forceuseragent Optional a user agent to force. */ protected function __construct($forceuseragent = null) {
< global $CFG; < if (!empty($CFG->devicedetectregex)) { < $this->devicetypecustoms = json_decode($CFG->devicedetectregex, true); < } < if ($this->devicetypecustoms === null) { < // This shouldn't happen unless you're hardcoding the config value. < debugging('Config devicedetectregex is not valid JSON object'); < $this->devicetypecustoms = array(); < }
if ($forceuseragent !== null) { $this->useragent = $forceuseragent; } else if (!empty($_SERVER['HTTP_USER_AGENT'])) { $this->useragent = $_SERVER['HTTP_USER_AGENT']; } else { $this->useragent = false; $this->devicetype = self::DEVICETYPE_DEFAULT; } } /** * Get the MoodleBot UserAgent for this site. * * @return string UserAgent */ public static function get_moodlebot_useragent() { global $CFG; $version = moodle_major_version(); // Only major version for security. return "MoodleBot/$version (+{$CFG->wwwroot})"; } /** * Returns the user agent string. * @return bool|string The user agent string or false if one isn't available. */ public static function get_user_agent_string() { $instance = self::instance(); return $instance->useragent; } /** * Returns the device type we believe is being used. * @return string */ public static function get_device_type() { $instance = self::instance(); if ($instance->devicetype === null) { return $instance->guess_device_type(); } return $instance->devicetype; } /** * Guesses the device type the user agent is running on. * * @return string */ protected function guess_device_type() {
< global $CFG; < if (empty($CFG->enabledevicedetection)) { < $this->devicetype = self::DEVICETYPE_DEFAULT; < return $this->devicetype; < } < foreach ($this->devicetypecustoms as $value => $regex) { < if (preg_match($regex, $this->useragent)) { < $this->devicetype = $value; < return $this->devicetype; < } < }
if ($this->is_useragent_mobile()) { $this->devicetype = self::DEVICETYPE_MOBILE; } else if ($this->is_useragent_tablet()) { $this->devicetype = self::DEVICETYPE_TABLET; } else if (self::check_ie_version('0') && !self::check_ie_version('7.0')) { // IE 6 and before are considered legacy. $this->devicetype = self::DEVICETYPE_LEGACY; } else { $this->devicetype = self::DEVICETYPE_DEFAULT; } return $this->devicetype; } /** * Returns true if the user appears to be on a mobile device. * @return bool */ protected function is_useragent_mobile() { // Mobile detection PHP direct copy from open source detectmobilebrowser.com. $phonesregex = '/android .+ mobile|avantgo|blackberry|blazer|compal|elaine|fennec|hiptop|iemobile|ip(hone|od)|iris|kindle|lge |maemo|midp|mmp|opera m(ob|in)i|palm( os)?|phone|p(ixi|re)\/|plucker|pocket|psp|symbian|treo|up\.(browser|link)|vodafone|wap|windows (ce|phone)|xda|xiino/i'; $modelsregex = '/1207|6310|6590|3gso|4thp|50[1-6]i|770s|802s|a wa|abac|ac(er|oo|s\-)|ai(ko|rn)|al(av|ca|co)|amoi|an(ex|ny|yw)|aptu|ar(ch|go)|as(te|us)|attw|au(di|\-m|r |s )|avan|be(ck|ll|nq)|bi(lb|rd)|bl(ac|az)|br(e|v)w|bumb|bw\-(n|u)|c55\/|capi|ccwa|cdm\-|cell|chtm|cldc|cmd\-|co(mp|nd)|craw|da(it|ll|ng)|dbte|dc\-s|devi|dica|dmob|do(c|p)o|ds(12|\-d)|el(49|ai)|em(l2|ul)|er(ic|k0)|esl8|ez([4-7]0|os|wa|ze)|fetc|fly(\-|_)|g1 u|g560|gene|gf\-5|g\-mo|go(\.w|od)|gr(ad|un)|haie|hcit|hd\-(m|p|t)|hei\-|hi(pt|ta)|hp( i|ip)|hs\-c|ht(c(\-| |_|a|g|p|s|t)|tp)|hu(aw|tc)|i\-(20|go|ma)|i230|iac( |\-|\/)|ibro|idea|ig01|ikom|im1k|inno|ipaq|iris|ja(t|v)a|jbro|jemu|jigs|kddi|keji|kgt( |\/)|klon|kpt |kwc\-|kyo(c|k)|le(no|xi)|lg( g|\/(k|l|u)|50|54|e\-|e\/|\-[a-w])|libw|lynx|m1\-w|m3ga|m50\/|ma(te|ui|xo)|mc(01|21|ca)|m\-cr|me(di|rc|ri)|mi(o8|oa|ts)|mmef|mo(01|02|bi|de|do|t(\-| |o|v)|zz)|mt(50|p1|v )|mwbp|mywa|n10[0-2]|n20[2-3]|n30(0|2)|n50(0|2|5)|n7(0(0|1)|10)|ne((c|m)\-|on|tf|wf|wg|wt)|nok(6|i)|nzph|o2im|op(ti|wv)|oran|owg1|p800|pan(a|d|t)|pdxg|pg(13|\-([1-8]|c))|phil|pire|pl(ay|uc)|pn\-2|po(ck|rt|se)|prox|psio|pt\-g|qa\-a|qc(07|12|21|32|60|\-[2-7]|i\-)|qtek|r380|r600|raks|rim9|ro(ve|zo)|s55\/|sa(ge|ma|mm|ms|ny|va)|sc(01|h\-|oo|p\-)|sdk\/|se(c(\-|0|1)|47|mc|nd|ri)|sgh\-|shar|sie(\-|m)|sk\-0|sl(45|id)|sm(al|ar|b3|it|t5)|so(ft|ny)|sp(01|h\-|v\-|v )|sy(01|mb)|t2(18|50)|t6(00|10|18)|ta(gt|lk)|tcl\-|tdg\-|tel(i|m)|tim\-|t\-mo|to(pl|sh)|ts(70|m\-|m3|m5)|tx\-9|up(\.b|g1|si)|utst|v400|v750|veri|vi(rg|te)|vk(40|5[0-3]|\-v)|vm40|voda|vulc|vx(52|53|60|61|70|80|81|83|85|98)|w3c(\-| )|webc|whit|wi(g |nc|nw)|wmlb|wonu|x700|xda(\-|2|g)|yas\-|your|zeto|zte\-/i'; return (preg_match($phonesregex, $this->useragent) || preg_match($modelsregex, substr($this->useragent, 0, 4))); } /** * Returns true if the user appears to be on a tablet. * * @return int */ protected function is_useragent_tablet() { $tabletregex = '/Tablet browser|android|iPad|iProd|GT-P1000|GT-I9000|SHW-M180S|SGH-T849|SCH-I800|Build\/ERE27|sholest/i'; return (preg_match($tabletregex, $this->useragent)); } /** * Whether the user agent relates to a web crawler. * This includes all types of web crawler. * @return bool */ protected function is_useragent_web_crawler() { $regex = '/MoodleBot|Googlebot|google\.com|Yahoo! Slurp|\[ZSEBOT\]|msnbot|bingbot|BingPreview|Yandex|AltaVista' .'|Baiduspider|Teoma/i'; return (preg_match($regex, $this->useragent)); } /** * Gets a list of known device types. *
> * @deprecated Moodle 4.3 MDL-78468 - No longer used. Please use core_useragent::devicetypes instead. * @param bool $includecustomtypes If set to true we'll include types that have been added by the admin. > * @todo Final deprecation on Moodle 4.7 MDL-79052
* @return array */ public static function get_device_type_list($includecustomtypes = true) {
> debugging( $types = self::$devicetypes; > __FUNCTION__ . '() is deprecated.' . if ($includecustomtypes) { > 'All functions associated with devicedetectregex theme setting are being removed. $instance = self::instance(); > Please use core_useragent::devicetypes instead', $types = array_merge($types, array_keys($instance->devicetypecustoms)); > DEBUG_DEVELOPER } > );
return $types; } /** * Returns the theme to use for the given device type. * * This used to be get_selected_theme_for_device_type. * @param null|string $devicetype The device type to find out for. Defaults to the device the user is using,
> * @deprecated since 4.3.
* @return bool */ public static function get_device_type_theme($devicetype = null) {
> debugging( global $CFG; > __FUNCTION__ . '() is deprecated.' . if ($devicetype === null) { > 'All functions associated with device specific themes are being removed.', $devicetype = self::get_device_type(); > DEBUG_DEVELOPER } > );
$themevarname = self::get_device_type_cfg_var_name($devicetype); if (empty($CFG->$themevarname)) { return false; } return $CFG->$themevarname; } /** * Returns the CFG var used to find the theme to use for the given device. * * Used to be get_device_cfg_var_name. * * @param null|string $devicetype The device type to find out for. Defaults to the device the user is using,
> * @deprecated since 4.3.
* @return string */ public static function get_device_type_cfg_var_name($devicetype = null) {
> debugging( if ($devicetype == self::DEVICETYPE_DEFAULT || empty($devicetype)) { > __FUNCTION__ . '() is deprecated.' . return 'theme'; > 'All functions associated with device specific themes are being removed.', } > DEBUG_DEVELOPER return 'theme' . $devicetype; > );
} /** * Gets the device type the user is currently using. * @return string */ public static function get_user_device_type() { $device = self::get_device_type(); $switched = get_user_preferences('switchdevice'.$device, false); if ($switched != false) { return $switched; } return $device; } /** * Switches the device type we think the user is using to what ever was given. * @param string $newdevice * @return bool * @throws coding_exception */ public static function set_user_device_type($newdevice) { $devicetype = self::get_device_type(); if ($newdevice == $devicetype) { unset_user_preference('switchdevice'.$devicetype); return true; } else {
< $devicetypes = self::get_device_type_list();
> $devicetypes = self::$devicetypes;
if (in_array($newdevice, $devicetypes)) { set_user_preference('switchdevice'.$devicetype, $newdevice); return true; } } throw new coding_exception('Invalid device type provided to set_user_device_type'); } /** * Returns true if the user agent matches the given brand and the version is equal to or greater than that specified. * * @param string $brand The branch to check for. * @param scalar $version The version if we need to find out if it is equal to or greater than that specified. * @return bool */ public static function check_browser_version($brand, $version = null) { switch ($brand) { case 'MSIE': // Internet Explorer. return self::check_ie_version($version); case 'Edge': // Microsoft Edge. return self::check_edge_version($version); case 'Firefox': // Mozilla Firefox browsers. return self::check_firefox_version($version); case 'Chrome': return self::check_chrome_version($version); case 'Opera': // Opera. return self::check_opera_version($version); case 'Safari': // Desktop version of Apple Safari browser - no mobile or touch devices. return self::check_safari_version($version); case 'Safari iOS': // Safari on iPhone, iPad and iPod touch. return self::check_safari_ios_version($version); case 'WebKit': // WebKit based browser - everything derived from it (Safari, Chrome, iOS, Android and other mobiles). return self::check_webkit_version($version); case 'Gecko': // Gecko based browsers. return self::check_gecko_version($version); case 'WebKit Android': // WebKit browser on Android. return self::check_webkit_android_version($version); case 'Camino': // OSX browser using Gecke engine. return self::check_camino_version($version); } // Who knows?! doesn't pass anyway. return false; } /** * Checks the user agent is camino based and that the version is equal to or greater than that specified. * * Camino browser is at the end of its life, its no longer being developed or supported, just don't worry about it. * * @param string|int $version A version to check for, returns true if its equal to or greater than that specified. * @return bool */ protected static function check_camino_version($version = null) { // OSX browser using Gecko engine. $useragent = self::get_user_agent_string(); if ($useragent === false) { return false; } if (strpos($useragent, 'Camino') === false) { return false; } if (empty($version)) { return true; // No version specified. } if (preg_match("/Camino\/([0-9\.]+)/i", $useragent, $match)) { if (version_compare($match[1], $version) >= 0) { return true; } } return false; } /** * Checks the user agent is Firefox (of any version). * * @return bool true if firefox */ public static function is_firefox() { return self::check_firefox_version(); } /** * Checks the user agent is Firefox based and that the version is equal to or greater than that specified. * * @param string|int $version A version to check for, returns true if its equal to or greater than that specified. * @return bool */ public static function check_firefox_version($version = null) { // Mozilla Firefox browsers. $useragent = self::get_user_agent_string(); if ($useragent === false) { return false; } if (strpos($useragent, 'Firefox') === false && strpos($useragent, 'Iceweasel') === false) { return false; } if (empty($version)) { return true; // No version specified.. } if (preg_match("/(Iceweasel|Firefox)\/([0-9\.]+)/i", $useragent, $match)) { if (version_compare($match[2], $version) >= 0) { return true; } } return false; } /** * Checks the user agent is Gecko based (of any version). * * @return bool true if Gecko based. */ public static function is_gecko() { return self::check_gecko_version(); } /** * Checks the user agent is Gecko based and that the version is equal to or greater than that specified. * * @param string|int $version A version to check for, returns true if its equal to or greater than that specified. * @return bool */ public static function check_gecko_version($version = null) { // Gecko based browsers. // Do not look for dates any more, we expect real Firefox version here. $useragent = self::get_user_agent_string(); if ($useragent === false) { return false; } if (empty($version)) { $version = 1; } else if ($version > 20000000) { // This is just a guess, it is not supposed to be 100% accurate! if (preg_match('/^201/', $version)) { $version = 3.6; } else if (preg_match('/^200[7-9]/', $version)) { $version = 3; } else if (preg_match('/^2006/', $version)) { $version = 2; } else { $version = 1.5; } } if (preg_match("/(Iceweasel|Firefox)\/([0-9\.]+)/i", $useragent, $match)) { // Use real Firefox version if specified in user agent string. if (version_compare($match[2], $version) >= 0) { return true; } } else if (preg_match("/Gecko\/([0-9\.]+)/i", $useragent, $match)) { // Gecko might contain date or Firefox revision, let's just guess the Firefox version from the date. $browserver = $match[1]; if ($browserver > 20000000) { // This is just a guess, it is not supposed to be 100% accurate! if (preg_match('/^201/', $browserver)) { $browserver = 3.6; } else if (preg_match('/^200[7-9]/', $browserver)) { $browserver = 3; } else if (preg_match('/^2006/', $version)) { $browserver = 2; } else { $browserver = 1.5; } } if (version_compare($browserver, $version) >= 0) { return true; } } return false; } /** * Checks the user agent is Edge (of any version). * * @return bool true if Edge */ public static function is_edge() { return self::check_edge_version(); } /** * Check the User Agent for the version of Edge. * * @param string|int $version A version to check for, returns true if its equal to or greater than that specified. * @return bool */ public static function check_edge_version($version = null) { $useragent = self::get_user_agent_string(); if ($useragent === false) { // No User Agent found. return false; } if (strpos($useragent, 'Edge/') === false) { // Edge was not found in the UA - this is not Edge. return false; } if (empty($version)) { // No version to check. return true; } // Find the version. // Edge versions are always in the format: // Edge/<version>.<OS build number> preg_match('%Edge/([\d]+)\.(.*)$%', $useragent, $matches); // Just to be safe, round the version being tested. // Edge only uses integer versions - the second component is the OS build number. $version = round($version); // Check whether the version specified is >= the version found. return version_compare($matches[1], $version, '>='); } /** * Checks the user agent is IE (of any version). * * @return bool true if internet exporeer */ public static function is_ie() { return self::check_ie_version(); } /** * Checks the user agent is IE and returns its main properties: * - browser version; * - whether running in compatibility view. * * @return bool|array False if not IE, otherwise an associative array of properties. */ public static function check_ie_properties() { // Internet Explorer. $useragent = self::get_user_agent_string(); if ($useragent === false) { return false; } if (strpos($useragent, 'Opera') !== false) { // Reject Opera. return false; } // See: http://www.useragentstring.com/pages/Internet%20Explorer/. if (preg_match("/MSIE ([0-9\.]+)/", $useragent, $match)) { $browser = $match[1]; // See: http://msdn.microsoft.com/en-us/library/ie/bg182625%28v=vs.85%29.aspx for IE11+ useragent details. } else if (preg_match("/Trident\/[0-9\.]+/", $useragent) && preg_match("/rv:([0-9\.]+)/", $useragent, $match)) { $browser = $match[1]; } else { return false; } $compatview = false; // IE8 and later versions may pretend to be IE7 for intranet sites, use Trident version instead, // the Trident should always describe the capabilities of IE in any emulation mode. if ($browser === '7.0' and preg_match("/Trident\/([0-9\.]+)/", $useragent, $match)) { $compatview = true; $browser = $match[1] + 4; // NOTE: Hopefully this will work also for future IE versions. } $browser = round($browser, 1); return array( 'version' => $browser, 'compatview' => $compatview ); } /** * Checks the user agent is IE and that the version is equal to or greater than that specified. * * @param string|int $version A version to check for, returns true if its equal to or greater than that specified. * @return bool */ public static function check_ie_version($version = null) { // Internet Explorer. $properties = self::check_ie_properties(); if (!is_array($properties)) { return false; } // In case of IE we have to deal with BC of the version parameter. if (is_null($version)) { $version = 5.5; // Anything older is not considered a browser at all! } // IE uses simple versions, let's cast it to float to simplify the logic here. $version = round($version, 1); return ($properties['version'] >= $version); } /** * Checks the user agent is IE and that IE is running under Compatibility View setting. * * @return bool true if internet explorer runs in Compatibility View mode. */ public static function check_ie_compatibility_view() { // IE User Agent string when in Compatibility View: // - IE 8: "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.1; Trident/4.0; ...)". // - IE 9: "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.1; Trident/5.0; ...)". // - IE 10: "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.1; Trident/6.0; ...)". // - IE 11: "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.3; Trident/7.0; ...)". // Refs: // - http://blogs.msdn.com/b/ie/archive/2009/01/09/the-internet-explorer-8-user-agent-string-updated-edition.aspx. // - http://blogs.msdn.com/b/ie/archive/2010/03/23/introducing-ie9-s-user-agent-string.aspx. // - http://blogs.msdn.com/b/ie/archive/2011/04/15/the-ie10-user-agent-string.aspx. // - http://msdn.microsoft.com/en-us/library/ie/hh869301%28v=vs.85%29.aspx. $properties = self::check_ie_properties(); if (!is_array($properties)) { return false; } return $properties['compatview']; } /** * Checks the user agent is Opera (of any version). * * @return bool true if opera */ public static function is_opera() { return self::check_opera_version(); } /** * Checks the user agent is Opera and that the version is equal to or greater than that specified. * * @param string|int $version A version to check for, returns true if its equal to or greater than that specified. * @return bool */ public static function check_opera_version($version = null) { // Opera. $useragent = self::get_user_agent_string(); if ($useragent === false) { return false; } if (strpos($useragent, 'Opera') === false) { return false; } if (empty($version)) { return true; // No version specified. } // Recent Opera useragents have Version/ with the actual version, e.g.: // Opera/9.80 (Windows NT 6.1; WOW64; U; en) Presto/2.10.289 Version/12.01 // That's Opera 12.01, not 9.8. if (preg_match("/Version\/([0-9\.]+)/i", $useragent, $match)) { if (version_compare($match[1], $version) >= 0) { return true; } } else if (preg_match("/Opera\/([0-9\.]+)/i", $useragent, $match)) { if (version_compare($match[1], $version) >= 0) { return true; } } return false; } /** * Checks the user agent is webkit based * * @return bool true if webkit */ public static function is_webkit() { return self::check_webkit_version(); } /** * Checks the user agent is Webkit based and that the version is equal to or greater than that specified. * * @param string|int $version A version to check for, returns true if its equal to or greater than that specified. * @return bool */ public static function check_webkit_version($version = null) { // WebKit based browser - everything derived from it (Safari, Chrome, iOS, Android and other mobiles). $useragent = self::get_user_agent_string(); if ($useragent === false) { return false; } if (strpos($useragent, 'AppleWebKit') === false) { return false; } if (empty($version)) { return true; // No version specified. } if (preg_match("/AppleWebKit\/([0-9.]+)/i", $useragent, $match)) { if (version_compare($match[1], $version) >= 0) { return true; } } return false; } /** * Checks the user agent is Safari * * @return bool true if safari */ public static function is_safari() { return self::check_safari_version(); } /** * Checks the user agent is Safari based and that the version is equal to or greater than that specified. * * @param string|int $version A version to check for, returns true if its equal to or greater than that specified. * @return bool */ public static function check_safari_version($version = null) { // Desktop version of Apple Safari browser - no mobile or touch devices. $useragent = self::get_user_agent_string(); if ($useragent === false) { return false; } if (strpos($useragent, 'AppleWebKit') === false) { return false; } // Look for AppleWebKit, excluding strings with OmniWeb, Shiira and SymbianOS and any other mobile devices. if (strpos($useragent, 'OmniWeb')) { // Reject OmniWeb. return false; } if (strpos($useragent, 'Shiira')) { // Reject Shiira. return false; } if (strpos($useragent, 'SymbianOS')) { // Reject SymbianOS. return false; } if (strpos($useragent, 'Android')) { // Reject Androids too. return false; } if (strpos($useragent, 'iPhone') or strpos($useragent, 'iPad') or strpos($useragent, 'iPod')) { // No Apple mobile devices here - editor does not work, course ajax is not touch compatible, etc. return false; } if (strpos($useragent, 'Chrome')) { // Reject chrome browsers - it needs to be tested explicitly. // This will also reject Edge, which pretends to be both Chrome, and Safari. return false; } if (empty($version)) { return true; // No version specified. } if (preg_match("/AppleWebKit\/([0-9.]+)/i", $useragent, $match)) { if (version_compare($match[1], $version) >= 0) { return true; } } return false; } /** * Checks the user agent is Chrome * * @return bool true if chrome */ public static function is_chrome() { return self::check_chrome_version(); } /** * Checks the user agent is Chrome based and that the version is equal to or greater than that specified. * * @param string|int $version A version to check for, returns true if its equal to or greater than that specified. * @return bool */ public static function check_chrome_version($version = null) { // Chrome. $useragent = self::get_user_agent_string(); if ($useragent === false) { return false; } if (strpos($useragent, 'Chrome') === false) { return false; } if (empty($version)) { return true; // No version specified. } if (preg_match("/Chrome\/(.*)[ ]+/i", $useragent, $match)) { if (version_compare($match[1], $version) >= 0) { return true; } } return false; } /** * Checks the user agent is webkit android based. * * @return bool true if webkit based and on Android */ public static function is_webkit_android() { return self::check_webkit_android_version(); } /** * Checks the user agent is Webkit based and on Android and that the version is equal to or greater than that specified. * * @param string|int $version A version to check for, returns true if its equal to or greater than that specified. * @return bool */ public static function check_webkit_android_version($version = null) { // WebKit browser on Android. $useragent = self::get_user_agent_string(); if ($useragent === false) { return false; } if (strpos($useragent, 'Android') === false) { return false; } if (empty($version)) { return true; // No version specified. } if (preg_match("/AppleWebKit\/([0-9]+)/i", $useragent, $match)) { if (version_compare($match[1], $version) >= 0) { return true; } } return false; } /** * Checks the user agent is Safari on iOS * * @return bool true if Safari on iOS */ public static function is_safari_ios() { return self::check_safari_ios_version(); } /** * Checks the user agent is Safari on iOS and that the version is equal to or greater than that specified. * * @param string|int $version A version to check for, returns true if its equal to or greater than that specified. * @return bool */ public static function check_safari_ios_version($version = null) { // Safari on iPhone, iPad and iPod touch. $useragent = self::get_user_agent_string(); if ($useragent === false) { return false; } if (strpos($useragent, 'AppleWebKit') === false or strpos($useragent, 'Safari') === false) { return false; } if (!strpos($useragent, 'iPhone') and !strpos($useragent, 'iPad') and !strpos($useragent, 'iPod')) { return false; } if (empty($version)) { return true; // No version specified. } if (preg_match("/AppleWebKit\/([0-9]+)/i", $useragent, $match)) { if (version_compare($match[1], $version) >= 0) { return true; } } return false; } /** * Checks if the user agent is MS Word. * Not perfect, as older versions of Word use standard IE6/7 user agents without any identifying traits. * * @return bool true if user agent could be identified as MS Word. */ public static function is_msword() { $useragent = self::get_user_agent_string(); if (!preg_match('/(\bWord\b|ms-office|MSOffice|Microsoft Office)/i', $useragent)) { return false; } else if (strpos($useragent, 'Outlook') !== false) { return false; } else if (strpos($useragent, 'Meridio') !== false) { return false; } // It's Office, not Outlook and not Meridio - so it's probably Word, but we can't really be sure in most cases. return true; } /** * Check if the user agent matches a given brand. * * Known brand: 'Windows','Linux','Macintosh','SGI','SunOS','HP-UX' * * @param string $brand * @return bool */ public static function check_browser_operating_system($brand) { $useragent = self::get_user_agent_string(); return ($useragent !== false && preg_match("/$brand/i", $useragent)); } /** * Gets an array of CSS classes to represent the user agent. * @return array */ public static function get_browser_version_classes() { $classes = array(); if (self::is_edge()) { $classes[] = 'edge'; } else if (self::is_ie()) { $classes[] = 'ie'; for ($i = 12; $i >= 6; $i--) { if (self::check_ie_version($i)) { $classes[] = 'ie'.$i; break; } } } else if (self::is_firefox() || self::is_gecko() || self::check_camino_version()) { $classes[] = 'gecko'; if (preg_match('/rv\:([1-2])\.([0-9])/', self::get_user_agent_string(), $matches)) { $classes[] = "gecko{$matches[1]}{$matches[2]}"; } } else if (self::is_chrome()) { $classes[] = 'chrome'; if (self::is_webkit_android()) { $classes[] = 'android'; } } else if (self::is_webkit()) { if (self::is_safari()) { $classes[] = 'safari'; } if (self::is_safari_ios()) { $classes[] = 'ios'; } else if (self::is_webkit_android()) { $classes[] = 'android'; // Old pre-Chrome android browsers. } } else if (self::is_opera()) { $classes[] = 'opera'; } return $classes; } /** * Returns true if the user agent supports the display of SVG images. * * @return bool */ public static function supports_svg() {
< // IE 5 - 8 don't support SVG at all.
$instance = self::instance(); if ($instance->supportssvg === null) {
< if ($instance->useragent === false) { < // Can't be sure, just say no. < $instance->supportssvg = false; < } else if (self::check_ie_version('0') and !self::check_ie_version('9')) { < // IE < 9 doesn't support SVG. Say no. < $instance->supportssvg = false; < } else if (self::is_ie() and !self::check_ie_version('10') and self::check_ie_compatibility_view()) { < // IE 9 Compatibility View doesn't support SVG. Say no. < $instance->supportssvg = false; < } else if (preg_match('#Android +[0-2]\.#', $instance->useragent)) { < // Android < 3 doesn't support SVG. Say no. < $instance->supportssvg = false; < } else if (self::is_opera()) { < // Opera 12 still does not support SVG well enough. Say no.
> if (preg_match('#Android +[0-2]\.#', $instance->useragent)) { > // Android < 3 doesn't support SVG.
$instance->supportssvg = false; } else {
< // Presumed fine.
> // With widespread SVG support in modern browsers, default to returning true (even when useragent is false).
$instance->supportssvg = true; } } return $instance->supportssvg; } /** * Returns true if the user agent supports the MIME media type for JSON text, as defined in RFC 4627. * * @return bool */ public static function supports_json_contenttype() { // Modern browsers other than IE correctly supports 'application/json' media type. if (!self::check_ie_version('0')) { return true; } // IE8+ supports 'application/json' media type, when NOT in Compatibility View mode. // Refs: // - http://blogs.msdn.com/b/ie/archive/2008/09/10/native-json-in-ie8.aspx; // - MDL-39810: issues when using 'text/plain' in Compatibility View for the body of an HTTP POST response. if (self::check_ie_version(8) && !self::check_ie_compatibility_view()) { return true; } // This browser does not support json. return false; } /** * Returns true if the client appears to be some kind of web crawler. * This may include other types of crawler. * * @return bool */ public static function is_web_crawler() { $instance = self::instance(); return (bool) $instance->is_useragent_web_crawler(); } /** * Returns true if the client appears to be a device using iOS (iPhone, iPad, iPod). * * @param scalar $version The version if we need to find out if it is equal to or greater than that specified. * @return bool true if the client is using iOS * @since Moodle 3.2 */ public static function is_ios($version = null) { $useragent = self::get_user_agent_string(); if ($useragent === false) { return false; } if (strpos($useragent, 'AppleWebKit') === false) { return false; } if (strpos($useragent, 'Windows')) { // Reject Windows Safari. return false; } if (strpos($useragent, 'Macintosh')) { // Reject MacOS Safari. return false; } // Look for AppleWebKit, excluding strings with OmniWeb, Shiira and SymbianOS and any other mobile devices. if (strpos($useragent, 'OmniWeb')) { // Reject OmniWeb. return false; } if (strpos($useragent, 'Shiira')) { // Reject Shiira. return false; } if (strpos($useragent, 'SymbianOS')) { // Reject SymbianOS. return false; } if (strpos($useragent, 'Android')) { // Reject Androids too. return false; } if (strpos($useragent, 'Chrome')) { // Reject chrome browsers - it needs to be tested explicitly. // This will also reject Edge, which pretends to be both Chrome, and Safari. return false; } if (empty($version)) { return true; // No version specified. } if (preg_match("/AppleWebKit\/([0-9.]+)/i", $useragent, $match)) { if (version_compare($match[1], $version) >= 0) { return true; } } return false; } /** * Returns true if the client appears to be the Moodle app (or an app based on the Moodle app code). * * @return bool true if the client is the Moodle app * @since Moodle 3.7 */ public static function is_moodle_app() { $useragent = self::get_user_agent_string(); // Make it case insensitive, things can change in the app or desktop app depending on the platform frameworks. if (stripos($useragent, 'MoodleMobile') !== false) { return true; } return false; } /** * Checks if current browser supports files with give extension as <video> or <audio> source * * Note, the check here is not 100% accurate! * * First, we do not know which codec is used in .mp4 or .webm files. Not all browsers support * all codecs. * * Also we assume that users of Firefox/Chrome/Safari do not use the ancient versions of browsers. * * We check the exact version for IE/Edge though. We know that there are still users of very old * versions that are afraid to upgrade or have slow IT department. * * Resources: * https://developer.mozilla.org/en-US/docs/Web/HTML/Supported_media_formats * https://en.wikipedia.org/wiki/HTML5_video * https://en.wikipedia.org/wiki/HTML5_Audio * * @param string $extension extension without leading . * @return bool */ public static function supports_html5($extension) { $extension = strtolower($extension); $supportedvideo = array('m4v', 'webm', 'ogv', 'mp4', 'mov', 'fmp4'); $supportedaudio = array('ogg', 'oga', 'aac', 'm4a', 'mp3', 'wav', 'flac'); // Basic extension support. if (!in_array($extension, $supportedvideo) && !in_array($extension, $supportedaudio)) { return false; } // MS IE support - version 9.0 or later. if (self::is_ie() && !self::check_ie_version('9.0')) { return false; } // MS Edge support - version 12.0 for desktop and 13.0 for mobile. if (self::is_edge()) { if (!self::check_edge_version('12.0')) { return false; } if (self::instance()->is_useragent_mobile() && !self::check_edge_version('13.0')) { return false; } } // Different exceptions. // Webm is not supported in IE, Edge and in Safari. if ($extension === 'webm' && (self::is_ie() || self::is_edge() || self::is_safari() || self::is_safari_ios())) { return false; } // Ogg is not supported in IE, Edge and Safari. $isogg = in_array($extension, ['ogg', 'oga', 'ogv']); if ($isogg && (self::is_ie() || self::is_edge() || self::is_safari() || self::is_safari_ios())) { return false; } // FLAC is not supported in IE and Edge (below 16.0). if ($extension === 'flac' && (self::is_ie() || (self::is_edge() && !self::check_edge_version('16.0')))) { return false; } // Wave is not supported in IE. if ($extension === 'wav' && self::is_ie()) { return false; } // Aac is not supported in IE below 11.0. if ($extension === 'aac' && (self::is_ie() && !self::check_ie_version('11.0'))) { return false; } // Mpeg is not supported in IE below 10.0. $ismpeg = in_array($extension, ['m4a', 'mp3', 'm4v', 'mp4', 'fmp4']); if ($ismpeg && (self::is_ie() && !self::check_ie_version('10.0'))) { return false; } // Mov is not supported in IE. if ($extension === 'mov' && self::is_ie()) { return false; } return true; } /** * Checks if current browser supports the HLS and MPEG-DASH media * streaming formats. Most browsers get this from Media Source Extensions. * Safari on iOS, doesn't support MPEG-DASH at all. * * Note, the check here is not 100% accurate! * * Also we assume that users of Firefox/Chrome/Safari do not use the ancient versions of browsers. * We check the exact version for IE/Edge though. We know that there are still users of very old * versions that are afraid to upgrade or have slow IT department. * * Resources: * https://developer.mozilla.org/en-US/docs/Web/API/Media_Source_Extensions_API * https://caniuse.com/#search=mpeg-dash * https://caniuse.com/#search=hls * * @param string $extension * @return bool */ public static function supports_media_source_extensions(string $extension) : bool { // Not supported in IE below 11.0. if (self::is_ie() && !self::check_ie_version('11.0')) { return false; } if ($extension == '.mpd') { // Not supported in Safari on iOS. if (self::is_safari_ios()) { return false; } } return true; } }