1<?php
  2/**
  3 * Creates common globals for the rest of WordPress
  4 *
  5 * Sets $pagenow global which is the filename of the current screen.
  6 * Checks for the browser to set which one is currently being used.
  7 *
  8 * Detects which user environment WordPress is being used on.
  9 * Only attempts to check for Apache, Nginx and IIS -- three web
 10 * servers with known pretty permalink capability.
 11 *
 12 * Note: Though Nginx is detected, WordPress does not currently
 13 * generate rewrite rules for it. See https://developer.wordpress.org/advanced-administration/server/web-server/nginx/
 14 *
 15 * @package WordPress
 16 */
 17
 18// Don't load directly.
 19if ( ! defined( 'ABSPATH' ) ) {
 20	die( '-1' );
 21}
 22
 23global $pagenow,
 24	$is_lynx, $is_gecko, $is_winIE, $is_macIE, $is_opera, $is_NS4, $is_safari, $is_chrome, $is_iphone, $is_IE, $is_edge,
 25	$is_apache, $is_IIS, $is_iis7, $is_nginx, $is_caddy;
 26
 27// On which page are we?
 28if ( is_admin() ) {
 29	// wp-admin pages are checked more carefully.
 30	if ( is_network_admin() ) {
 31		preg_match( '#/wp-admin/network/?(.*?)$#i', $_SERVER['PHP_SELF'], $self_matches );
 32	} elseif ( is_user_admin() ) {
 33		preg_match( '#/wp-admin/user/?(.*?)$#i', $_SERVER['PHP_SELF'], $self_matches );
 34	} else {
 35		preg_match( '#/wp-admin/?(.*?)$#i', $_SERVER['PHP_SELF'], $self_matches );
 36	}
 37
 38	$pagenow = ! empty( $self_matches[1] ) ? $self_matches[1] : '';
 39	$pagenow = trim( $pagenow, '/' );
 40	$pagenow = preg_replace( '#\?.*?$#', '', $pagenow );
 41
 42	if ( '' === $pagenow || 'index' === $pagenow || 'index.php' === $pagenow ) {
 43		$pagenow = 'index.php';
 44	} else {
 45		preg_match( '#(.*?)(/|$)#', $pagenow, $self_matches );
 46		$pagenow = strtolower( $self_matches[1] );
 47		if ( ! str_ends_with( $pagenow, '.php' ) ) {
 48			$pagenow .= '.php'; // For `Options +Multiviews`: /wp-admin/themes/index.php (themes.php is queried).
 49		}
 50	}
 51} else {
 52	if ( preg_match( '#([^/]+\.php)([?/].*?)?$#i', $_SERVER['PHP_SELF'], $self_matches ) ) {
 53		$pagenow = strtolower( $self_matches[1] );
 54	} else {
 55		$pagenow = 'index.php';
 56	}
 57}
 58unset( $self_matches );
 59
 60// Simple browser detection.
 61$is_lynx   = false;
 62$is_gecko  = false;
 63$is_winIE  = false;
 64$is_macIE  = false;
 65$is_opera  = false;
 66$is_NS4    = false;
 67$is_safari = false;
 68$is_chrome = false;
 69$is_iphone = false;
 70$is_edge   = false;
 71
 72if ( isset( $_SERVER['HTTP_USER_AGENT'] ) ) {
 73	if ( str_contains( $_SERVER['HTTP_USER_AGENT'], 'Lynx' ) ) {
 74		$is_lynx = true;
 75	} elseif ( str_contains( $_SERVER['HTTP_USER_AGENT'], 'Edg' ) ) {
 76		$is_edge = true;
 77	} elseif ( str_contains( $_SERVER['HTTP_USER_AGENT'], 'Opera' ) || str_contains( $_SERVER['HTTP_USER_AGENT'], 'OPR/' ) ) {
 78		$is_opera = true;
 79	} elseif ( stripos( $_SERVER['HTTP_USER_AGENT'], 'chrome' ) !== false ) {
 80		if ( stripos( $_SERVER['HTTP_USER_AGENT'], 'chromeframe' ) !== false ) {
 81			$is_admin = is_admin();
 82			/**
 83			 * Filters whether Google Chrome Frame should be used, if available.
 84			 *
 85			 * @since 3.2.0
 86			 *
 87			 * @param bool $is_admin Whether to use the Google Chrome Frame. Default is the value of is_admin().
 88			 */
 89			$is_chrome = apply_filters( 'use_google_chrome_frame', $is_admin );
 90			if ( $is_chrome ) {
 91				header( 'X-UA-Compatible: chrome=1' );
 92			}
 93			$is_winIE = ! $is_chrome;
 94		} else {
 95			$is_chrome = true;
 96		}
 97	} elseif ( stripos( $_SERVER['HTTP_USER_AGENT'], 'safari' ) !== false ) {
 98		$is_safari = true;
 99	} elseif ( ( str_contains( $_SERVER['HTTP_USER_AGENT'], 'MSIE' ) || str_contains( $_SERVER['HTTP_USER_AGENT'], 'Trident' ) )
100		&& str_contains( $_SERVER['HTTP_USER_AGENT'], 'Win' )
101	) {
102		$is_winIE = true;
103	} elseif ( str_contains( $_SERVER['HTTP_USER_AGENT'], 'MSIE' ) && str_contains( $_SERVER['HTTP_USER_AGENT'], 'Mac' ) ) {
104		$is_macIE = true;
105	} elseif ( str_contains( $_SERVER['HTTP_USER_AGENT'], 'Gecko' ) ) {
106		$is_gecko = true;
107	} elseif ( str_contains( $_SERVER['HTTP_USER_AGENT'], 'Nav' ) && str_contains( $_SERVER['HTTP_USER_AGENT'], 'Mozilla/4.' ) ) {
108		$is_NS4 = true;
109	}
110}
111
112if ( $is_safari && stripos( $_SERVER['HTTP_USER_AGENT'], 'mobile' ) !== false ) {
113	$is_iphone = true;
114}
115
116$is_IE = ( $is_macIE || $is_winIE );
117
118// Server detection.
119
120/**
121 * Whether the server software is Apache or something else.
122 *
123 * @global bool $is_apache
124 */
125$is_apache = ( str_contains( $_SERVER['SERVER_SOFTWARE'], 'Apache' ) || str_contains( $_SERVER['SERVER_SOFTWARE'], 'LiteSpeed' ) );
126
127/**
128 * Whether the server software is Nginx or something else.
129 *
130 * @global bool $is_nginx
131 */
132$is_nginx = ( str_contains( $_SERVER['SERVER_SOFTWARE'], 'nginx' ) );
133
134/**
135 * Whether the server software is Caddy / FrankenPHP or something else.
136 *
137 * @global bool $is_caddy
138 */
139$is_caddy = ( str_contains( $_SERVER['SERVER_SOFTWARE'], 'Caddy' ) || str_contains( $_SERVER['SERVER_SOFTWARE'], 'FrankenPHP' ) );
140
141/**
142 * Whether the server software is IIS or something else.
143 *
144 * @global bool $is_IIS
145 */
146$is_IIS = ! $is_apache && ( str_contains( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS' ) || str_contains( $_SERVER['SERVER_SOFTWARE'], 'ExpressionDevServer' ) );
147
148/**
149 * Whether the server software is IIS 7.X or greater.
150 *
151 * @global bool $is_iis7
152 */
153$is_iis7 = $is_IIS && (int) substr( $_SERVER['SERVER_SOFTWARE'], strpos( $_SERVER['SERVER_SOFTWARE'], 'Microsoft-IIS/' ) + 14 ) >= 7;
154
155/**
156 * Test if the current browser runs on a mobile device (smart phone, tablet, etc.).
157 *
158 * @since 3.4.0
159 * @since 6.4.0 Added checking for the Sec-CH-UA-Mobile request header.
160 *
161 * @return bool
162 */
163function wp_is_mobile() {
164	if ( isset( $_SERVER['HTTP_SEC_CH_UA_MOBILE'] ) ) {
165		// This is the `Sec-CH-UA-Mobile` user agent client hint HTTP request header.
166		// See <https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Sec-CH-UA-Mobile>.
167		$is_mobile = ( '?1' === $_SERVER['HTTP_SEC_CH_UA_MOBILE'] );
168	} elseif ( empty( $_SERVER['HTTP_USER_AGENT'] ) ) {
169		$is_mobile = false;
170	} elseif ( str_contains( $_SERVER['HTTP_USER_AGENT'], 'Mobile' ) // Many mobile devices (all iPhone, iPad, etc.)
171		|| str_contains( $_SERVER['HTTP_USER_AGENT'], 'Android' )
172		|| str_contains( $_SERVER['HTTP_USER_AGENT'], 'Silk/' )
173		|| str_contains( $_SERVER['HTTP_USER_AGENT'], 'Kindle' )
174		|| str_contains( $_SERVER['HTTP_USER_AGENT'], 'BlackBerry' )
175		|| str_contains( $_SERVER['HTTP_USER_AGENT'], 'Opera Mini' )
176		|| str_contains( $_SERVER['HTTP_USER_AGENT'], 'Opera Mobi' ) ) {
177			$is_mobile = true;
178	} else {
179		$is_mobile = false;
180	}
181
182	/**
183	 * Filters whether the request should be treated as coming from a mobile device or not.
184	 *
185	 * @since 4.9.0
186	 *
187	 * @param bool $is_mobile Whether the request is from a mobile device or not.
188	 */
189	return apply_filters( 'wp_is_mobile', $is_mobile );
190}
191