source: tags/4.6.1/src/wp-includes/pluggable.php

<?php
/**
 * These functions can be replaced via plugins. If plugins do not redefine these
 * functions, then these will be used instead.
 *
 * @package WordPress
 */

if ( !function_exists('wp_set_current_user') ) :
/**
 * Changes the current user by ID or name.
 *
 * Set $id to null and specify a name if you do not know a user's ID.
 *
 * Some WordPress functionality is based on the current user and not based on
 * the signed in user. Therefore, it opens the ability to edit and perform
 * actions on users who aren't signed in.
 *
 * @since 2.0.3
 * @global WP_User $current_user The current user object which holds the user data.
 *
 * @param int    $id   User ID
 * @param string $name User's username
 * @return WP_User Current user User object
 */
function wp_set_current_user($id, $name = '') {
        global $current_user;

        // If `$id` matches the user who's already current, there's nothing to do.
        if ( isset( $current_user )
                && ( $current_user instanceof WP_User )
                && ( $id == $current_user->ID )
                && ( null !== $id )
        ) {
                return $current_user;
        }

        $current_user = new WP_User( $id, $name );

        setup_userdata( $current_user->ID );

        /**
         * Fires after the current user is set.
         *
         * @since 2.0.1
         */
        do_action( 'set_current_user' );

        return $current_user;
}
endif;

if ( !function_exists('wp_get_current_user') ) :
/**
 * Retrieve the current user object.
 *
 * Will set the current user, if the current user is not set. The current user
 * will be set to the logged-in person. If no user is logged-in, then it will
 * set the current user to 0, which is invalid and won't have any permissions.
 *
 * @since 2.0.3
 *
 * @see _wp_get_current_user()
 * @global WP_User $current_user Checks if the current user is set.
 *
 * @return WP_User Current WP_User instance.
 */
function wp_get_current_user() {
        return _wp_get_current_user();
}
endif;

if ( !function_exists('get_userdata') ) :
/**
 * Retrieve user info by user ID.
 *
 * @since 0.71
 *
 * @param int $user_id User ID
 * @return WP_User|false WP_User object on success, false on failure.
 */
function get_userdata( $user_id ) {
        return get_user_by( 'id', $user_id );
}
endif;

if ( !function_exists('get_user_by') ) :
/**
 * Retrieve user info by a given field
 *
 * @since 2.8.0
 * @since 4.4.0 Added 'ID' as an alias of 'id' for the `$field` parameter.
 *
 * @param string     $field The field to retrieve the user with. id | ID | slug | email | login.
 * @param int|string $value A value for $field. A user ID, slug, email address, or login name.
 * @return WP_User|false WP_User object on success, false on failure.
 */
function get_user_by( $field, $value ) {
        $userdata = WP_User::get_data_by( $field, $value );

        if ( !$userdata )
                return false;

        $user = new WP_User;
        $user->init( $userdata );

        return $user;
}
endif;

if ( !function_exists('cache_users') ) :
/**
 * Retrieve info for user lists to prevent multiple queries by get_userdata()
 *
 * @since 3.0.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param array $user_ids User ID numbers list
 */
function cache_users( $user_ids ) {
        global $wpdb;

        $clean = _get_non_cached_ids( $user_ids, 'users' );

        if ( empty( $clean ) )
                return;

        $list = implode( ',', $clean );

        $users = $wpdb->get_results( "SELECT * FROM $wpdb->users WHERE ID IN ($list)" );

        $ids = array();
        foreach ( $users as $user ) {
                update_user_caches( $user );
                $ids[] = $user->ID;
        }
        update_meta_cache( 'user', $ids );
}
endif;

if ( !function_exists( 'wp_mail' ) ) :
/**
 * Send mail, similar to PHP's mail
 *
 * A true return value does not automatically mean that the user received the
 * email successfully. It just only means that the method used was able to
 * process the request without any errors.
 *
 * Using the two 'wp_mail_from' and 'wp_mail_from_name' hooks allow from
 * creating a from address like 'Name <email@address.com>' when both are set. If
 * just 'wp_mail_from' is set, then just the email address will be used with no
 * name.
 *
 * The default content type is 'text/plain' which does not allow using HTML.
 * However, you can set the content type of the email by using the
 * {@see 'wp_mail_content_type'} filter.
 *
 * The default charset is based on the charset used on the blog. The charset can
 * be set using the {@see 'wp_mail_charset'} filter.
 *
 * @since 1.2.1
 *
 * @global PHPMailer $phpmailer
 *
 * @param string|array $to          Array or comma-separated list of email addresses to send message.
 * @param string       $subject     Email subject
 * @param string       $message     Message contents
 * @param string|array $headers     Optional. Additional headers.
 * @param string|array $attachments Optional. Files to attach.
 * @return bool Whether the email contents were sent successfully.
 */
function wp_mail( $to, $subject, $message, $headers = '', $attachments = array() ) {
        // Compact the input, apply the filters, and extract them back out

        /**
         * Filters the wp_mail() arguments.
         *
         * @since 2.2.0
         *
         * @param array $args A compacted array of wp_mail() arguments, including the "to" email,
         *                    subject, message, headers, and attachments values.
         */
        $atts = apply_filters( 'wp_mail', compact( 'to', 'subject', 'message', 'headers', 'attachments' ) );

        if ( isset( $atts['to'] ) ) {
                $to = $atts['to'];
        }

        if ( isset( $atts['subject'] ) ) {
                $subject = $atts['subject'];
        }

        if ( isset( $atts['message'] ) ) {
                $message = $atts['message'];
        }

        if ( isset( $atts['headers'] ) ) {
                $headers = $atts['headers'];
        }

        if ( isset( $atts['attachments'] ) ) {
                $attachments = $atts['attachments'];
        }

        if ( ! is_array( $attachments ) ) {
                $attachments = explode( "\n", str_replace( "\r\n", "\n", $attachments ) );
        }
        global $phpmailer;

        // (Re)create it, if it's gone missing
        if ( ! ( $phpmailer instanceof PHPMailer ) ) {
                require_once ABSPATH . WPINC . '/class-phpmailer.php';
                require_once ABSPATH . WPINC . '/class-smtp.php';
                $phpmailer = new PHPMailer( true );
        }

        // Headers
        $cc = $bcc = $reply_to = array();

        if ( empty( $headers ) ) {
                $headers = array();
        } else {
                if ( !is_array( $headers ) ) {
                        // Explode the headers out, so this function can take both
                        // string headers and an array of headers.
                        $tempheaders = explode( "\n", str_replace( "\r\n", "\n", $headers ) );
                } else {
                        $tempheaders = $headers;
                }
                $headers = array();

                // If it's actually got contents
                if ( !empty( $tempheaders ) ) {
                        // Iterate through the raw headers
                        foreach ( (array) $tempheaders as $header ) {
                                if ( strpos($header, ':') === false ) {
                                        if ( false !== stripos( $header, 'boundary=' ) ) {
                                                $parts = preg_split('/boundary=/i', trim( $header ) );
                                                $boundary = trim( str_replace( array( "'", '"' ), '', $parts[1] ) );
                                        }
                                        continue;
                                }
                                // Explode them out
                                list( $name, $content ) = explode( ':', trim( $header ), 2 );

                                // Cleanup crew
                                $name    = trim( $name    );
                                $content = trim( $content );

                                switch ( strtolower( $name ) ) {
                                        // Mainly for legacy -- process a From: header if it's there
                                        case 'from':
                                                $bracket_pos = strpos( $content, '<' );
                                                if ( $bracket_pos !== false ) {
                                                        // Text before the bracketed email is the "From" name.
                                                        if ( $bracket_pos > 0 ) {
                                                                $from_name = substr( $content, 0, $bracket_pos - 1 );
                                                                $from_name = str_replace( '"', '', $from_name );
                                                                $from_name = trim( $from_name );
                                                        }

                                                        $from_email = substr( $content, $bracket_pos + 1 );
                                                        $from_email = str_replace( '>', '', $from_email );
                                                        $from_email = trim( $from_email );

                                                // Avoid setting an empty $from_email.
                                                } elseif ( '' !== trim( $content ) ) {
                                                        $from_email = trim( $content );
                                                }
                                                break;
                                        case 'content-type':
                                                if ( strpos( $content, ';' ) !== false ) {
                                                        list( $type, $charset_content ) = explode( ';', $content );
                                                        $content_type = trim( $type );
                                                        if ( false !== stripos( $charset_content, 'charset=' ) ) {
                                                                $charset = trim( str_replace( array( 'charset=', '"' ), '', $charset_content ) );
                                                        } elseif ( false !== stripos( $charset_content, 'boundary=' ) ) {
                                                                $boundary = trim( str_replace( array( 'BOUNDARY=', 'boundary=', '"' ), '', $charset_content ) );
                                                                $charset = '';
                                                        }

                                                // Avoid setting an empty $content_type.
                                                } elseif ( '' !== trim( $content ) ) {
                                                        $content_type = trim( $content );
                                                }
                                                break;
                                        case 'cc':
                                                $cc = array_merge( (array) $cc, explode( ',', $content ) );
                                                break;
                                        case 'bcc':
                                                $bcc = array_merge( (array) $bcc, explode( ',', $content ) );
                                                break;
                                        case 'reply-to':
                                                $reply_to = array_merge( (array) $reply_to, explode( ',', $content ) );
                                                break;
                                        default:
                                                // Add it to our grand headers array
                                                $headers[trim( $name )] = trim( $content );
                                                break;
                                }
                        }
                }
        }

        // Empty out the values that may be set
        $phpmailer->ClearAllRecipients();
        $phpmailer->ClearAttachments();
        $phpmailer->ClearCustomHeaders();
        $phpmailer->ClearReplyTos();

        // From email and name
        // If we don't have a name from the input headers
        if ( !isset( $from_name ) )
                $from_name = 'WordPress';

        /* If we don't have an email from the input headers default to wordpress@$sitename
         * Some hosts will block outgoing mail from this address if it doesn't exist but
         * there's no easy alternative. Defaulting to admin_email might appear to be another
         * option but some hosts may refuse to relay mail from an unknown domain. See
         * https://core.trac.wordpress.org/ticket/5007.
         */

        if ( !isset( $from_email ) ) {
                // Get the site domain and get rid of www.
                $sitename = strtolower( $_SERVER['SERVER_NAME'] );
                if ( substr( $sitename, 0, 4 ) == 'www.' ) {
                        $sitename = substr( $sitename, 4 );
                }

                $from_email = 'wordpress@' . $sitename;
        }

        /**
         * Filters the email address to send from.
         *
         * @since 2.2.0
         *
         * @param string $from_email Email address to send from.
         */
        $from_email = apply_filters( 'wp_mail_from', $from_email );

        /**
         * Filters the name to associate with the "from" email address.
         *
         * @since 2.3.0
         *
         * @param string $from_name Name associated with the "from" email address.
         */
        $from_name = apply_filters( 'wp_mail_from_name', $from_name );

        $phpmailer->setFrom( $from_email, $from_name, false );

        // Set destination addresses
        if ( !is_array( $to ) )
                $to = explode( ',', $to );

        // Set mail's subject and body
        $phpmailer->Subject = $subject;
        $phpmailer->Body    = $message;

        // Use appropriate methods for handling addresses, rather than treating them as generic headers
        $address_headers = compact( 'to', 'cc', 'bcc', 'reply_to' );

        foreach ( $address_headers as $address_header => $addresses ) {
                if ( empty( $addresses ) ) {
                        continue;
                }

                foreach ( (array) $addresses as $address ) {
                        try {
                                // Break $recipient into name and address parts if in the format "Foo <bar@baz.com>"
                                $recipient_name = '';

                                if ( preg_match( '/(.*)<(.+)>/', $address, $matches ) ) {
                                        if ( count( $matches ) == 3 ) {
                                                $recipient_name = $matches[1];
                                                $address        = $matches[2];
                                        }
                                }

                                switch ( $address_header ) {
                                        case 'to':
                                                $phpmailer->addAddress( $address, $recipient_name );
                                                break;
                                        case 'cc':
                                                $phpmailer->addCc( $address, $recipient_name );
                                                break;
                                        case 'bcc':
                                                $phpmailer->addBcc( $address, $recipient_name );
                                                break;
                                        case 'reply_to':
                                                $phpmailer->addReplyTo( $address, $recipient_name );
                                                break;
                                }
                        } catch ( phpmailerException $e ) {
                                continue;
                        }
                }
        }

        // Set to use PHP's mail()
        $phpmailer->IsMail();

        // Set Content-Type and charset
        // If we don't have a content-type from the input headers
        if ( !isset( $content_type ) )
                $content_type = 'text/plain';

        /**
         * Filters the wp_mail() content type.
         *
         * @since 2.3.0
         *
         * @param string $content_type Default wp_mail() content type.
         */
        $content_type = apply_filters( 'wp_mail_content_type', $content_type );

        $phpmailer->ContentType = $content_type;

        // Set whether it's plaintext, depending on $content_type
        if ( 'text/html' == $content_type )
                $phpmailer->IsHTML( true );

        // If we don't have a charset from the input headers
        if ( !isset( $charset ) )
                $charset = get_bloginfo( 'charset' );

        // Set the content-type and charset

        /**
         * Filters the default wp_mail() charset.
         *
         * @since 2.3.0
         *
         * @param string $charset Default email charset.
         */
        $phpmailer->CharSet = apply_filters( 'wp_mail_charset', $charset );

        // Set custom headers
        if ( !empty( $headers ) ) {
                foreach ( (array) $headers as $name => $content ) {
                        $phpmailer->AddCustomHeader( sprintf( '%1$s: %2$s', $name, $content ) );
                }

                if ( false !== stripos( $content_type, 'multipart' ) && ! empty($boundary) )
                        $phpmailer->AddCustomHeader( sprintf( "Content-Type: %s;\n\t boundary=\"%s\"", $content_type, $boundary ) );
        }

        if ( !empty( $attachments ) ) {
                foreach ( $attachments as $attachment ) {
                        try {
                                $phpmailer->AddAttachment($attachment);
                        } catch ( phpmailerException $e ) {
                                continue;
                        }
                }
        }

        /**
         * Fires after PHPMailer is initialized.
         *
         * @since 2.2.0
         *
         * @param PHPMailer &$phpmailer The PHPMailer instance, passed by reference.
         */
        do_action_ref_array( 'phpmailer_init', array( &$phpmailer ) );

        // Send!
        try {
                return $phpmailer->Send();
        } catch ( phpmailerException $e ) {

                $mail_error_data = compact( 'to', 'subject', 'message', 'headers', 'attachments' );

                /**
                 * Fires after a phpmailerException is caught.
                 *
                 * @since 4.4.0
                 *
                 * @param WP_Error $error A WP_Error object with the phpmailerException code, message, and an array
                 *                        containing the mail recipient, subject, message, headers, and attachments.
                 */
                do_action( 'wp_mail_failed', new WP_Error( $e->getCode(), $e->getMessage(), $mail_error_data ) );

                return false;
        }
}
endif;

if ( !function_exists('wp_authenticate') ) :
/**
 * Authenticate a user, confirming the login credentials are valid.
 *
 * @since 2.5.0
 * @since 4.5.0 `$username` now accepts an email address.
 *
 * @param string $username User's username or email address.
 * @param string $password User's password.
 * @return WP_User|WP_Error WP_User object if the credentials are valid,
 *                          otherwise WP_Error.
 */
function wp_authenticate($username, $password) {
        $username = sanitize_user($username);
        $password = trim($password);

        /**
         * Filters whether a set of user login credentials are valid.
         *
         * A WP_User object is returned if the credentials authenticate a user.
         * WP_Error or null otherwise.
         *
         * @since 2.8.0
         * @since 4.5.0 `$username` now accepts an email address.
         *
         * @param null|WP_User|WP_Error $user     WP_User if the user is authenticated.
         *                                        WP_Error or null otherwise.
         * @param string                $username Username or email address.
         * @param string                $password User password
         */
        $user = apply_filters( 'authenticate', null, $username, $password );

        if ( $user == null ) {
                // TODO what should the error message be? (Or would these even happen?)
                // Only needed if all authentication handlers fail to return anything.
                $user = new WP_Error( 'authentication_failed', __( '<strong>ERROR</strong>: Invalid username, email address or incorrect password.' ) );
        }

        $ignore_codes = array('empty_username', 'empty_password');

        if (is_wp_error($user) && !in_array($user->get_error_code(), $ignore_codes) ) {
                /**
                 * Fires after a user login has failed.
                 *
                 * @since 2.5.0
                 * @since 4.5.0 The value of `$username` can now be an email address.
                 *
                 * @param string $username Username or email address.
                 */
                do_action( 'wp_login_failed', $username );
        }

        return $user;
}
endif;

if ( !function_exists('wp_logout') ) :
/**
 * Log the current user out.
 *
 * @since 2.5.0
 */
function wp_logout() {
        wp_destroy_current_session();
        wp_clear_auth_cookie();

        /**
         * Fires after a user is logged-out.
         *
         * @since 1.5.0
         */
        do_action( 'wp_logout' );
}
endif;

if ( !function_exists('wp_validate_auth_cookie') ) :
/**
 * Validates authentication cookie.
 *
 * The checks include making sure that the authentication cookie is set and
 * pulling in the contents (if $cookie is not used).
 *
 * Makes sure the cookie is not expired. Verifies the hash in cookie is what is
 * should be and compares the two.
 *
 * @since 2.5.0
 *
 * @global int $login_grace_period
 *
 * @param string $cookie Optional. If used, will validate contents instead of cookie's
 * @param string $scheme Optional. The cookie scheme to use: auth, secure_auth, or logged_in
 * @return false|int False if invalid cookie, User ID if valid.
 */
function wp_validate_auth_cookie($cookie = '', $scheme = '') {
        if ( ! $cookie_elements = wp_parse_auth_cookie($cookie, $scheme) ) {
                /**
                 * Fires if an authentication cookie is malformed.
                 *
                 * @since 2.7.0
                 *
                 * @param string $cookie Malformed auth cookie.
                 * @param string $scheme Authentication scheme. Values include 'auth', 'secure_auth',
                 *                       or 'logged_in'.
                 */
                do_action( 'auth_cookie_malformed', $cookie, $scheme );
                return false;
        }

        $scheme = $cookie_elements['scheme'];
        $username = $cookie_elements['username'];
        $hmac = $cookie_elements['hmac'];
        $token = $cookie_elements['token'];
        $expired = $expiration = $cookie_elements['expiration'];

        // Allow a grace period for POST and Ajax requests
        if ( defined('DOING_AJAX') || 'POST' == $_SERVER['REQUEST_METHOD'] ) {
                $expired += HOUR_IN_SECONDS;
        }

        // Quick check to see if an honest cookie has expired
        if ( $expired < time() ) {
                /**
                 * Fires once an authentication cookie has expired.
                 *
                 * @since 2.7.0
                 *
                 * @param array $cookie_elements An array of data for the authentication cookie.
                 */
                do_action( 'auth_cookie_expired', $cookie_elements );
                return false;
        }

        $user = get_user_by('login', $username);
        if ( ! $user ) {
                /**
                 * Fires if a bad username is entered in the user authentication process.
                 *
                 * @since 2.7.0
                 *
                 * @param array $cookie_elements An array of data for the authentication cookie.
                 */
                do_action( 'auth_cookie_bad_username', $cookie_elements );
                return false;
        }

        $pass_frag = substr($user->user_pass, 8, 4);

        $key = wp_hash( $username . '|' . $pass_frag . '|' . $expiration . '|' . $token, $scheme );

        // If ext/hash is not present, compat.php's hash_hmac() does not support sha256.
        $algo = function_exists( 'hash' ) ? 'sha256' : 'sha1';
        $hash = hash_hmac( $algo, $username . '|' . $expiration . '|' . $token, $key );

        if ( ! hash_equals( $hash, $hmac ) ) {
                /**
                 * Fires if a bad authentication cookie hash is encountered.
                 *
                 * @since 2.7.0
                 *
                 * @param array $cookie_elements An array of data for the authentication cookie.
                 */
                do_action( 'auth_cookie_bad_hash', $cookie_elements );
                return false;
        }

        $manager = WP_Session_Tokens::get_instance( $user->ID );
        if ( ! $manager->verify( $token ) ) {
                do_action( 'auth_cookie_bad_session_token', $cookie_elements );
                return false;
        }

        // Ajax/POST grace period set above
        if ( $expiration < time() ) {
                $GLOBALS['login_grace_period'] = 1;
        }

        /**
         * Fires once an authentication cookie has been validated.
         *
         * @since 2.7.0
         *
         * @param array   $cookie_elements An array of data for the authentication cookie.
         * @param WP_User $user            User object.
         */
        do_action( 'auth_cookie_valid', $cookie_elements, $user );

        return $user->ID;
}
endif;

if ( !function_exists('wp_generate_auth_cookie') ) :
/**
 * Generate authentication cookie contents.
 *
 * @since 2.5.0
 *
 * @param int    $user_id    User ID
 * @param int    $expiration The time the cookie expires as a UNIX timestamp.
 * @param string $scheme     Optional. The cookie scheme to use: auth, secure_auth, or logged_in
 * @param string $token      User's session token to use for this cookie
 * @return string Authentication cookie contents. Empty string if user does not exist.
 */
function wp_generate_auth_cookie( $user_id, $expiration, $scheme = 'auth', $token = '' ) {
        $user = get_userdata($user_id);
        if ( ! $user ) {
                return '';
        }

        if ( ! $token ) {
                $manager = WP_Session_Tokens::get_instance( $user_id );
                $token = $manager->create( $expiration );
        }

        $pass_frag = substr($user->user_pass, 8, 4);

        $key = wp_hash( $user->user_login . '|' . $pass_frag . '|' . $expiration . '|' . $token, $scheme );

        // If ext/hash is not present, compat.php's hash_hmac() does not support sha256.
        $algo = function_exists( 'hash' ) ? 'sha256' : 'sha1';
        $hash = hash_hmac( $algo, $user->user_login . '|' . $expiration . '|' . $token, $key );

        $cookie = $user->user_login . '|' . $expiration . '|' . $token . '|' . $hash;

        /**
         * Filters the authentication cookie.
         *
         * @since 2.5.0
         *
         * @param string $cookie     Authentication cookie.
         * @param int    $user_id    User ID.
         * @param int    $expiration The time the cookie expires as a UNIX timestamp.
         * @param string $scheme     Cookie scheme used. Accepts 'auth', 'secure_auth', or 'logged_in'.
         * @param string $token      User's session token used.
         */
        return apply_filters( 'auth_cookie', $cookie, $user_id, $expiration, $scheme, $token );
}
endif;

if ( !function_exists('wp_parse_auth_cookie') ) :
/**
 * Parse a cookie into its components
 *
 * @since 2.7.0
 *
 * @param string $cookie
 * @param string $scheme Optional. The cookie scheme to use: auth, secure_auth, or logged_in
 * @return array|false Authentication cookie components
 */
function wp_parse_auth_cookie($cookie = '', $scheme = '') {
        if ( empty($cookie) ) {
                switch ($scheme){
                        case 'auth':
                                $cookie_name = AUTH_COOKIE;
                                break;
                        case 'secure_auth':
                                $cookie_name = SECURE_AUTH_COOKIE;
                                break;
                        case "logged_in":
                                $cookie_name = LOGGED_IN_COOKIE;
                                break;
                        default:
                                if ( is_ssl() ) {
                                        $cookie_name = SECURE_AUTH_COOKIE;
                                        $scheme = 'secure_auth';
                                } else {
                                        $cookie_name = AUTH_COOKIE;
                                        $scheme = 'auth';
                                }
            }

                if ( empty($_COOKIE[$cookie_name]) )
                        return false;
                $cookie = $_COOKIE[$cookie_name];
        }

        $cookie_elements = explode('|', $cookie);
        if ( count( $cookie_elements ) !== 4 ) {
                return false;
        }

        list( $username, $expiration, $token, $hmac ) = $cookie_elements;

        return compact( 'username', 'expiration', 'token', 'hmac', 'scheme' );
}
endif;

if ( !function_exists('wp_set_auth_cookie') ) :
/**
 * Log in a user by setting authentication cookies.
 *
 * The $remember parameter increases the time that the cookie will be kept. The
 * default the cookie is kept without remembering is two days. When $remember is
 * set, the cookies will be kept for 14 days or two weeks.
 *
 * @since 2.5.0
 * @since 4.3.0 Added the `$token` parameter.
 *
 * @param int    $user_id  User ID
 * @param bool   $remember Whether to remember the user
 * @param mixed  $secure   Whether the admin cookies should only be sent over HTTPS.
 *                         Default is_ssl().
 * @param string $token    Optional. User's session token to use for this cookie.
 */
function wp_set_auth_cookie( $user_id, $remember = false, $secure = '', $token = '' ) {
        if ( $remember ) {
                /**
                 * Filters the duration of the authentication cookie expiration period.
                 *
                 * @since 2.8.0
                 *
                 * @param int  $length   Duration of the expiration period in seconds.
                 * @param int  $user_id  User ID.
                 * @param bool $remember Whether to remember the user login. Default false.
                 */
                $expiration = time() + apply_filters( 'auth_cookie_expiration', 14 * DAY_IN_SECONDS, $user_id, $remember );

                /*
                 * Ensure the browser will continue to send the cookie after the expiration time is reached.
                 * Needed for the login grace period in wp_validate_auth_cookie().
                 */
                $expire = $expiration + ( 12 * HOUR_IN_SECONDS );
        } else {
                /** This filter is documented in wp-includes/pluggable.php */
                $expiration = time() + apply_filters( 'auth_cookie_expiration', 2 * DAY_IN_SECONDS, $user_id, $remember );
                $expire = 0;
        }

        if ( '' === $secure ) {
                $secure = is_ssl();
        }

        // Front-end cookie is secure when the auth cookie is secure and the site's home URL is forced HTTPS.
        $secure_logged_in_cookie = $secure && 'https' === parse_url( get_option( 'home' ), PHP_URL_SCHEME );

        /**
         * Filters whether the connection is secure.
         *
         * @since 3.1.0
         *
         * @param bool $secure  Whether the connection is secure.
         * @param int  $user_id User ID.
         */
        $secure = apply_filters( 'secure_auth_cookie', $secure, $user_id );

        /**
         * Filters whether to use a secure cookie when logged-in.
         *
         * @since 3.1.0
         *
         * @param bool $secure_logged_in_cookie Whether to use a secure cookie when logged-in.
         * @param int  $user_id                 User ID.
         * @param bool $secure                  Whether the connection is secure.
         */
        $secure_logged_in_cookie = apply_filters( 'secure_logged_in_cookie', $secure_logged_in_cookie, $user_id, $secure );

        if ( $secure ) {
                $auth_cookie_name = SECURE_AUTH_COOKIE;
                $scheme = 'secure_auth';
        } else {
                $auth_cookie_name = AUTH_COOKIE;
                $scheme = 'auth';
        }

        if ( '' === $token ) {
                $manager = WP_Session_Tokens::get_instance( $user_id );
                $token   = $manager->create( $expiration );
        }

        $auth_cookie = wp_generate_auth_cookie( $user_id, $expiration, $scheme, $token );
        $logged_in_cookie = wp_generate_auth_cookie( $user_id, $expiration, 'logged_in', $token );

        /**
         * Fires immediately before the authentication cookie is set.
         *
         * @since 2.5.0
         *
         * @param string $auth_cookie Authentication cookie.
         * @param int    $expire      The time the login grace period expires as a UNIX timestamp.
         *                            Default is 12 hours past the cookie's expiration time.
         * @param int    $expiration  The time when the authentication cookie expires as a UNIX timestamp.
         *                            Default is 14 days from now.
         * @param int    $user_id     User ID.
         * @param string $scheme      Authentication scheme. Values include 'auth', 'secure_auth', or 'logged_in'.
         */
        do_action( 'set_auth_cookie', $auth_cookie, $expire, $expiration, $user_id, $scheme );

        /**
         * Fires immediately before the logged-in authentication cookie is set.
         *
         * @since 2.6.0
         *
         * @param string $logged_in_cookie The logged-in cookie.
         * @param int    $expire           The time the login grace period expires as a UNIX timestamp.
         *                                 Default is 12 hours past the cookie's expiration time.
         * @param int    $expiration       The time when the logged-in authentication cookie expires as a UNIX timestamp.
         *                                 Default is 14 days from now.
         * @param int    $user_id          User ID.
         * @param string $scheme           Authentication scheme. Default 'logged_in'.
         */
        do_action( 'set_logged_in_cookie', $logged_in_cookie, $expire, $expiration, $user_id, 'logged_in' );

        setcookie($auth_cookie_name, $auth_cookie, $expire, PLUGINS_COOKIE_PATH, COOKIE_DOMAIN, $secure, true);
        setcookie($auth_cookie_name, $auth_cookie, $expire, ADMIN_COOKIE_PATH, COOKIE_DOMAIN, $secure, true);
        setcookie(LOGGED_IN_COOKIE, $logged_in_cookie, $expire, COOKIEPATH, COOKIE_DOMAIN, $secure_logged_in_cookie, true);
        if ( COOKIEPATH != SITECOOKIEPATH )
                setcookie(LOGGED_IN_COOKIE, $logged_in_cookie, $expire, SITECOOKIEPATH, COOKIE_DOMAIN, $secure_logged_in_cookie, true);
}
endif;

if ( !function_exists('wp_clear_auth_cookie') ) :
/**
 * Removes all of the cookies associated with authentication.
 *
 * @since 2.5.0
 */
function wp_clear_auth_cookie() {
        /**
         * Fires just before the authentication cookies are cleared.
         *
         * @since 2.7.0
         */
        do_action( 'clear_auth_cookie' );

        setcookie( AUTH_COOKIE,        ' ', time() - YEAR_IN_SECONDS, ADMIN_COOKIE_PATH,   COOKIE_DOMAIN );
        setcookie( SECURE_AUTH_COOKIE, ' ', time() - YEAR_IN_SECONDS, ADMIN_COOKIE_PATH,   COOKIE_DOMAIN );
        setcookie( AUTH_COOKIE,        ' ', time() - YEAR_IN_SECONDS, PLUGINS_COOKIE_PATH, COOKIE_DOMAIN );
        setcookie( SECURE_AUTH_COOKIE, ' ', time() - YEAR_IN_SECONDS, PLUGINS_COOKIE_PATH, COOKIE_DOMAIN );
        setcookie( LOGGED_IN_COOKIE,   ' ', time() - YEAR_IN_SECONDS, COOKIEPATH,          COOKIE_DOMAIN );
        setcookie( LOGGED_IN_COOKIE,   ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH,      COOKIE_DOMAIN );

        // Old cookies
        setcookie( AUTH_COOKIE,        ' ', time() - YEAR_IN_SECONDS, COOKIEPATH,     COOKIE_DOMAIN );
        setcookie( AUTH_COOKIE,        ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH, COOKIE_DOMAIN );
        setcookie( SECURE_AUTH_COOKIE, ' ', time() - YEAR_IN_SECONDS, COOKIEPATH,     COOKIE_DOMAIN );
        setcookie( SECURE_AUTH_COOKIE, ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH, COOKIE_DOMAIN );

        // Even older cookies
        setcookie( USER_COOKIE, ' ', time() - YEAR_IN_SECONDS, COOKIEPATH,     COOKIE_DOMAIN );
        setcookie( PASS_COOKIE, ' ', time() - YEAR_IN_SECONDS, COOKIEPATH,     COOKIE_DOMAIN );
        setcookie( USER_COOKIE, ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH, COOKIE_DOMAIN );
        setcookie( PASS_COOKIE, ' ', time() - YEAR_IN_SECONDS, SITECOOKIEPATH, COOKIE_DOMAIN );
}
endif;

if ( !function_exists('is_user_logged_in') ) :
/**
 * Checks if the current visitor is a logged in user.
 *
 * @since 2.0.0
 *
 * @return bool True if user is logged in, false if not logged in.
 */
function is_user_logged_in() {
        $user = wp_get_current_user();

        return $user->exists();
}
endif;

if ( !function_exists('auth_redirect') ) :
/**
 * Checks if a user is logged in, if not it redirects them to the login page.
 *
 * @since 1.5.0
 */
function auth_redirect() {
        // Checks if a user is logged in, if not redirects them to the login page

        $secure = ( is_ssl() || force_ssl_admin() );

        /**
         * Filters whether to use a secure authentication redirect.
         *
         * @since 3.1.0
         *
         * @param bool $secure Whether to use a secure authentication redirect. Default false.
         */
        $secure = apply_filters( 'secure_auth_redirect', $secure );

        // If https is required and request is http, redirect
        if ( $secure && !is_ssl() && false !== strpos($_SERVER['REQUEST_URI'], 'wp-admin') ) {
                if ( 0 === strpos( $_SERVER['REQUEST_URI'], 'http' ) ) {
                        wp_redirect( set_url_scheme( $_SERVER['REQUEST_URI'], 'https' ) );
                        exit();
                } else {
                        wp_redirect( 'https://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'] );
                        exit();
                }
        }

        /**
         * Filters the authentication redirect scheme.
         *
         * @since 2.9.0
         *
         * @param string $scheme Authentication redirect scheme. Default empty.
         */
        $scheme = apply_filters( 'auth_redirect_scheme', '' );

        if ( $user_id = wp_validate_auth_cookie( '',  $scheme) ) {
                /**
                 * Fires before the authentication redirect.
                 *
                 * @since 2.8.0
                 *
                 * @param int $user_id User ID.
                 */
                do_action( 'auth_redirect', $user_id );

                // If the user wants ssl but the session is not ssl, redirect.
                if ( !$secure && get_user_option('use_ssl', $user_id) && false !== strpos($_SERVER['REQUEST_URI'], 'wp-admin') ) {
                        if ( 0 === strpos( $_SERVER['REQUEST_URI'], 'http' ) ) {
                                wp_redirect( set_url_scheme( $_SERVER['REQUEST_URI'], 'https' ) );
                                exit();
                        } else {
                                wp_redirect( 'https://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'] );
                                exit();
                        }
                }

                return;  // The cookie is good so we're done
        }

        // The cookie is no good so force login
        nocache_headers();

        $redirect = ( strpos( $_SERVER['REQUEST_URI'], '/options.php' ) && wp_get_referer() ) ? wp_get_referer() : set_url_scheme( 'http://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'] );

        $login_url = wp_login_url($redirect, true);

        wp_redirect($login_url);
        exit();
}
endif;

if ( !function_exists('check_admin_referer') ) :
/**
 * Makes sure that a user was referred from another admin page.
 *
 * To avoid security exploits.
 *
 * @since 1.2.0
 *
 * @param int|string $action    Action nonce.
 * @param string     $query_arg Optional. Key to check for nonce in `$_REQUEST` (since 2.5).
 *                              Default '_wpnonce'.
 * @return false|int False if the nonce is invalid, 1 if the nonce is valid and generated between
 *                   0-12 hours ago, 2 if the nonce is valid and generated between 12-24 hours ago.
 */
function check_admin_referer( $action = -1, $query_arg = '_wpnonce' ) {
        if ( -1 == $action )
                _doing_it_wrong( __FUNCTION__, __( 'You should specify a nonce action to be verified by using the first parameter.' ), '3.2.0' );

        $adminurl = strtolower(admin_url());
        $referer = strtolower(wp_get_referer());
        $result = isset($_REQUEST[$query_arg]) ? wp_verify_nonce($_REQUEST[$query_arg], $action) : false;

        /**
         * Fires once the admin request has been validated or not.
         *
         * @since 1.5.1
         *
         * @param string    $action The nonce action.
         * @param false|int $result False if the nonce is invalid, 1 if the nonce is valid and generated between
         *                          0-12 hours ago, 2 if the nonce is valid and generated between 12-24 hours ago.
         */
        do_action( 'check_admin_referer', $action, $result );

        if ( ! $result && ! ( -1 == $action && strpos( $referer, $adminurl ) === 0 ) ) {
                wp_nonce_ays( $action );
                die();
        }

        return $result;
}
endif;

if ( !function_exists('check_ajax_referer') ) :
/**
 * Verifies the Ajax request to prevent processing requests external of the blog.
 *
 * @since 2.0.3
 *
 * @param int|string   $action    Action nonce.
 * @param false|string $query_arg Optional. Key to check for the nonce in `$_REQUEST` (since 2.5). If false,
 *                                `$_REQUEST` values will be evaluated for '_ajax_nonce', and '_wpnonce'
 *                                (in that order). Default false.
 * @param bool         $die       Optional. Whether to die early when the nonce cannot be verified.
 *                                Default true.
 * @return false|int False if the nonce is invalid, 1 if the nonce is valid and generated between
 *                   0-12 hours ago, 2 if the nonce is valid and generated between 12-24 hours ago.
 */
function check_ajax_referer( $action = -1, $query_arg = false, $die = true ) {
        $nonce = '';

        if ( $query_arg && isset( $_REQUEST[ $query_arg ] ) )
                $nonce = $_REQUEST[ $query_arg ];
        elseif ( isset( $_REQUEST['_ajax_nonce'] ) )
                $nonce = $_REQUEST['_ajax_nonce'];
        elseif ( isset( $_REQUEST['_wpnonce'] ) )
                $nonce = $_REQUEST['_wpnonce'];

        $result = wp_verify_nonce( $nonce, $action );

        /**
         * Fires once the Ajax request has been validated or not.
         *
         * @since 2.1.0
         *
         * @param string    $action The Ajax nonce action.
         * @param false|int $result False if the nonce is invalid, 1 if the nonce is valid and generated between
         *                          0-12 hours ago, 2 if the nonce is valid and generated between 12-24 hours ago.
         */
        do_action( 'check_ajax_referer', $action, $result );

        if ( $die && false === $result ) {
                if ( defined( 'DOING_AJAX' ) && DOING_AJAX ) {
                        wp_die( -1 );
                } else {
                        die( '-1' );
                }
        }

        return $result;
}
endif;

if ( !function_exists('wp_redirect') ) :
/**
 * Redirects to another page.
 *
 * Note: wp_redirect() does not exit automatically, and should almost always be
 * followed by a call to `exit;`:
 *
 *     wp_redirect( $url );
 *     exit;
 *
 * Exiting can also be selectively manipulated by using wp_redirect() as a conditional
 * in conjunction with the {@see 'wp_redirect'} and {@see 'wp_redirect_location'} hooks:
 *
 *     if ( wp_redirect( $url ) {
 *         exit;
 *     }
 *
 * @since 1.5.1
 *
 * @global bool $is_IIS
 *
 * @param string $location The path to redirect to.
 * @param int    $status   Status code to use.
 * @return bool False if $location is not provided, true otherwise.
 */
function wp_redirect($location, $status = 302) {
        global $is_IIS;

        /**
         * Filters the redirect location.
         *
         * @since 2.1.0
         *
         * @param string $location The path to redirect to.
         * @param int    $status   Status code to use.
         */
        $location = apply_filters( 'wp_redirect', $location, $status );

        /**
         * Filters the redirect status code.
         *
         * @since 2.3.0
         *
         * @param int    $status   Status code to use.
         * @param string $location The path to redirect to.
         */
        $status = apply_filters( 'wp_redirect_status', $status, $location );

        if ( ! $location )
                return false;

        $location = wp_sanitize_redirect($location);

        if ( !$is_IIS && PHP_SAPI != 'cgi-fcgi' )
                status_header($status); // This causes problems on IIS and some FastCGI setups

        header("Location: $location", true, $status);

        return true;
}
endif;

if ( !function_exists('wp_sanitize_redirect') ) :
/**
 * Sanitizes a URL for use in a redirect.
 *
 * @since 2.3.0
 *
 * @param string $location The path to redirect to.
 * @return string Redirect-sanitized URL.
 **/
function wp_sanitize_redirect($location) {
        $regex = '/
                (
                        (?: [\xC2-\xDF][\x80-\xBF]        # double-byte sequences   110xxxxx 10xxxxxx
                        |   \xE0[\xA0-\xBF][\x80-\xBF]    # triple-byte sequences   1110xxxx 10xxxxxx * 2
                        |   [\xE1-\xEC][\x80-\xBF]{2}
                        |   \xED[\x80-\x9F][\x80-\xBF]
                        |   [\xEE-\xEF][\x80-\xBF]{2}
                        |   \xF0[\x90-\xBF][\x80-\xBF]{2} # four-byte sequences   11110xxx 10xxxxxx * 3
                        |   [\xF1-\xF3][\x80-\xBF]{3}
                        |   \xF4[\x80-\x8F][\x80-\xBF]{2}
                ){1,40}                              # ...one or more times
                )/x';
        $location = preg_replace_callback( $regex, '_wp_sanitize_utf8_in_redirect', $location );
        $location = preg_replace('|[^a-z0-9-~+_.?#=&;,/:%!*\[\]()@]|i', '', $location);
        $location = wp_kses_no_null($location);

        // remove %0d and %0a from location
        $strip = array('%0d', '%0a', '%0D', '%0A');
        return _deep_replace( $strip, $location );
}

/**
 * URL encode UTF-8 characters in a URL.
 *
 * @ignore
 * @since 4.2.0
 * @access private
 *
 * @see wp_sanitize_redirect()
 *
 * @param array $matches RegEx matches against the redirect location.
 * @return string URL-encoded version of the first RegEx match.
 */
function _wp_sanitize_utf8_in_redirect( $matches ) {
        return urlencode( $matches[0] );
}
endif;

if ( !function_exists('wp_safe_redirect') ) :
/**
 * Performs a safe (local) redirect, using wp_redirect().
 *
 * Checks whether the $location is using an allowed host, if it has an absolute
 * path. A plugin can therefore set or remove allowed host(s) to or from the
 * list.
 *
 * If the host is not allowed, then the redirect defaults to wp-admin on the siteurl
 * instead. This prevents malicious redirects which redirect to another host,
 * but only used in a few places.
 *
 * @since 2.3.0
 *
 * @param string $location The path to redirect to.
 * @param int    $status   Status code to use.
 */
function wp_safe_redirect($location, $status = 302) {

        // Need to look at the URL the way it will end up in wp_redirect()
        $location = wp_sanitize_redirect($location);

        /**
         * Filters the redirect fallback URL for when the provided redirect is not safe (local).
         *
         * @since 4.3.0
         *
         * @param string $fallback_url The fallback URL to use by default.
         * @param int    $status       The redirect status.
         */
        $location = wp_validate_redirect( $location, apply_filters( 'wp_safe_redirect_fallback', admin_url(), $status ) );

        wp_redirect($location, $status);
}
endif;

if ( !function_exists('wp_validate_redirect') ) :
/**
 * Validates a URL for use in a redirect.
 *
 * Checks whether the $location is using an allowed host, if it has an absolute
 * path. A plugin can therefore set or remove allowed host(s) to or from the
 * list.
 *
 * If the host is not allowed, then the redirect is to $default supplied
 *
 * @since 2.8.1
 *
 * @param string $location The redirect to validate
 * @param string $default  The value to return if $location is not allowed
 * @return string redirect-sanitized URL
 **/
function wp_validate_redirect($location, $default = '') {
        $location = trim( $location );
        // browsers will assume 'http' is your protocol, and will obey a redirect to a URL starting with '//'
        if ( substr($location, 0, 2) == '//' )
                $location = 'http:' . $location;

        // In php 5 parse_url may fail if the URL query part contains http://, bug #38143
        $test = ( $cut = strpos($location, '?') ) ? substr( $location, 0, $cut ) : $location;

        // @-operator is used to prevent possible warnings in PHP < 5.3.3.
        $lp = @parse_url($test);

        // Give up if malformed URL
        if ( false === $lp )
                return $default;

        // Allow only http and https schemes. No data:, etc.
        if ( isset($lp['scheme']) && !('http' == $lp['scheme'] || 'https' == $lp['scheme']) )
                return $default;

        // Reject if certain components are set but host is not. This catches urls like https:host.com for which parse_url does not set the host field.
        if ( ! isset( $lp['host'] ) && ( isset( $lp['scheme'] ) || isset( $lp['user'] ) || isset( $lp['pass'] ) || isset( $lp['port'] ) ) ) {
                return $default;
        }

        // Reject malformed components parse_url() can return on odd inputs.
        foreach ( array( 'user', 'pass', 'host' ) as $component ) {
                if ( isset( $lp[ $component ] ) && strpbrk( $lp[ $component ], ':/?#@' ) ) {
                        return $default;
                }
        }

        $wpp = parse_url(home_url());

        /**
         * Filters the whitelist of hosts to redirect to.
         *
         * @since 2.3.0
         *
         * @param array       $hosts An array of allowed hosts.
         * @param bool|string $host  The parsed host; empty if not isset.
         */
        $allowed_hosts = (array) apply_filters( 'allowed_redirect_hosts', array($wpp['host']), isset($lp['host']) ? $lp['host'] : '' );

        if ( isset($lp['host']) && ( !in_array($lp['host'], $allowed_hosts) && $lp['host'] != strtolower($wpp['host'])) )
                $location = $default;

        return $location;
}
endif;

if ( ! function_exists('wp_notify_postauthor') ) :
/**
 * Notify an author (and/or others) of a comment/trackback/pingback on a post.
 *
 * @since 1.0.0
 *
 * @param int|WP_Comment  $comment_id Comment ID or WP_Comment object.
 * @param string          $deprecated Not used
 * @return bool True on completion. False if no email addresses were specified.
 */
function wp_notify_postauthor( $comment_id, $deprecated = null ) {
        if ( null !== $deprecated ) {
                _deprecated_argument( __FUNCTION__, '3.8.0' );
        }

        $comment = get_comment( $comment_id );
        if ( empty( $comment ) || empty( $comment->comment_post_ID ) )
                return false;

        $post    = get_post( $comment->comment_post_ID );
        $author  = get_userdata( $post->post_author );

        // Who to notify? By default, just the post author, but others can be added.
        $emails = array();
        if ( $author ) {
                $emails[] = $author->user_email;
        }

        /**
         * Filters the list of email addresses to receive a comment notification.
         *
         * By default, only post authors are notified of comments. This filter allows
         * others to be added.
         *
         * @since 3.7.0
         *
         * @param array $emails     An array of email addresses to receive a comment notification.
         * @param int   $comment_id The comment ID.
         */
        $emails = apply_filters( 'comment_notification_recipients', $emails, $comment->comment_ID );
        $emails = array_filter( $emails );

        // If there are no addresses to send the comment to, bail.
        if ( ! count( $emails ) ) {
                return false;
        }

        // Facilitate unsetting below without knowing the keys.
        $emails = array_flip( $emails );

        /**
         * Filters whether to notify comment authors of their comments on their own posts.
         *
         * By default, comment authors aren't notified of their comments on their own
         * posts. This filter allows you to override that.
         *
         * @since 3.8.0
         *
         * @param bool $notify     Whether to notify the post author of their own comment.
         *                         Default false.
         * @param int  $comment_id The comment ID.
         */
        $notify_author = apply_filters( 'comment_notification_notify_author', false, $comment->comment_ID );

        // The comment was left by the author
        if ( $author && ! $notify_author && $comment->user_id == $post->post_author ) {
                unset( $emails[ $author->user_email ] );
        }

        // The author moderated a comment on their own post
        if ( $author && ! $notify_author && $post->post_author == get_current_user_id() ) {
                unset( $emails[ $author->user_email ] );
        }

        // The post author is no longer a member of the blog
        if ( $author && ! $notify_author && ! user_can( $post->post_author, 'read_post', $post->ID ) ) {
                unset( $emails[ $author->user_email ] );
        }

        // If there's no email to send the comment to, bail, otherwise flip array back around for use below
        if ( ! count( $emails ) ) {
                return false;
        } else {
                $emails = array_flip( $emails );
        }

        $comment_author_domain = @gethostbyaddr($comment->comment_author_IP);

        // The blogname option is escaped with esc_html on the way into the database in sanitize_option
        // we want to reverse this for the plain text arena of emails.
        $blogname = wp_specialchars_decode(get_option('blogname'), ENT_QUOTES);
        $comment_content = wp_specialchars_decode( $comment->comment_content );

        switch ( $comment->comment_type ) {
                case 'trackback':
                        $notify_message  = sprintf( __( 'New trackback on your post "%s"' ), $post->post_title ) . "\r\n";
                        /* translators: 1: website name, 2: website IP, 3: website hostname */
                        $notify_message .= sprintf( __('Website: %1$s (IP: %2$s, %3$s)'), $comment->comment_author, $comment->comment_author_IP, $comment_author_domain ) . "\r\n";
                        $notify_message .= sprintf( __( 'URL: %s' ), $comment->comment_author_url ) . "\r\n";
                        $notify_message .= sprintf( __( 'Comment: %s' ), "\r\n" . $comment_content ) . "\r\n\r\n";
                        $notify_message .= __( 'You can see all trackbacks on this post here:' ) . "\r\n";
                        /* translators: 1: blog name, 2: post title */
                        $subject = sprintf( __('[%1$s] Trackback: "%2$s"'), $blogname, $post->post_title );
                        break;
                case 'pingback':
                        $notify_message  = sprintf( __( 'New pingback on your post "%s"' ), $post->post_title ) . "\r\n";
                        /* translators: 1: website name, 2: website IP, 3: website hostname */
                        $notify_message .= sprintf( __('Website: %1$s (IP: %2$s, %3$s)'), $comment->comment_author, $comment->comment_author_IP, $comment_author_domain ) . "\r\n";
                        $notify_message .= sprintf( __( 'URL: %s' ), $comment->comment_author_url ) . "\r\n";
                        $notify_message .= sprintf( __( 'Comment: %s' ), "\r\n" . $comment_content ) . "\r\n\r\n";
                        $notify_message .= __( 'You can see all pingbacks on this post here:' ) . "\r\n";
                        /* translators: 1: blog name, 2: post title */
                        $subject = sprintf( __('[%1$s] Pingback: "%2$s"'), $blogname, $post->post_title );
                        break;
                default: // Comments
                        $notify_message  = sprintf( __( 'New comment on your post "%s"' ), $post->post_title ) . "\r\n";
                        /* translators: 1: comment author, 2: author IP, 3: author domain */
                        $notify_message .= sprintf( __( 'Author: %1$s (IP: %2$s, %3$s)' ), $comment->comment_author, $comment->comment_author_IP, $comment_author_domain ) . "\r\n";
                        $notify_message .= sprintf( __( 'Email: %s' ), $comment->comment_author_email ) . "\r\n";
                        $notify_message .= sprintf( __( 'URL: %s' ), $comment->comment_author_url ) . "\r\n";
                        $notify_message .= sprintf( __('Comment: %s' ), "\r\n" . $comment_content ) . "\r\n\r\n";
                        $notify_message .= __( 'You can see all comments on this post here:' ) . "\r\n";
                        /* translators: 1: blog name, 2: post title */
                        $subject = sprintf( __('[%1$s] Comment: "%2$s"'), $blogname, $post->post_title );
                        break;
        }
        $notify_message .= get_permalink($comment->comment_post_ID) . "#comments\r\n\r\n";
        $notify_message .= sprintf( __('Permalink: %s'), get_comment_link( $comment ) ) . "\r\n";

        if ( user_can( $post->post_author, 'edit_comment', $comment->comment_ID ) ) {
                if ( EMPTY_TRASH_DAYS ) {
                        $notify_message .= sprintf( __( 'Trash it: %s' ), admin_url( "comment.php?action=trash&c={$comment->comment_ID}#wpbody-content" ) ) . "\r\n";
                } else {
                        $notify_message .= sprintf( __( 'Delete it: %s' ), admin_url( "comment.php?action=delete&c={$comment->comment_ID}#wpbody-content" ) ) . "\r\n";
                }
                $notify_message .= sprintf( __( 'Spam it: %s' ), admin_url( "comment.php?action=spam&c={$comment->comment_ID}#wpbody-content" ) ) . "\r\n";
        }

        $wp_email = 'wordpress@' . preg_replace('#^www\.#', '', strtolower($_SERVER['SERVER_NAME']));

        if ( '' == $comment->comment_author ) {
                $from = "From: \"$blogname\" <$wp_email>";
                if ( '' != $comment->comment_author_email )
                        $reply_to = "Reply-To: $comment->comment_author_email";
        } else {
                $from = "From: \"$comment->comment_author\" <$wp_email>";
                if ( '' != $comment->comment_author_email )
                        $reply_to = "Reply-To: \"$comment->comment_author_email\" <$comment->comment_author_email>";
        }

        $message_headers = "$from\n"
                . "Content-Type: text/plain; charset=\"" . get_option('blog_charset') . "\"\n";

        if ( isset($reply_to) )
                $message_headers .= $reply_to . "\n";

        /**
         * Filters the comment notification email text.
         *
         * @since 1.5.2
         *
         * @param string $notify_message The comment notification email text.
         * @param int    $comment_id     Comment ID.
         */
        $notify_message = apply_filters( 'comment_notification_text', $notify_message, $comment->comment_ID );

        /**
         * Filters the comment notification email subject.
         *
         * @since 1.5.2
         *
         * @param string $subject    The comment notification email subject.
         * @param int    $comment_id Comment ID.
         */
        $subject = apply_filters( 'comment_notification_subject', $subject, $comment->comment_ID );

        /**
         * Filters the comment notification email headers.
         *
         * @since 1.5.2
         *
         * @param string $message_headers Headers for the comment notification email.
         * @param int    $comment_id      Comment ID.
         */
        $message_headers = apply_filters( 'comment_notification_headers', $message_headers, $comment->comment_ID );

        foreach ( $emails as $email ) {
                @wp_mail( $email, wp_specialchars_decode( $subject ), $notify_message, $message_headers );
        }

        return true;
}
endif;

if ( !function_exists('wp_notify_moderator') ) :
/**
 * Notifies the moderator of the site about a new comment that is awaiting approval.
 *
 * @since 1.0.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * Uses the {@see 'notify_moderator'} filter to determine whether the site moderator
 * should be notified, overriding the site setting.
 *
 * @param int $comment_id Comment ID.
 * @return true Always returns true.
 */
function wp_notify_moderator($comment_id) {
        global $wpdb;

        $maybe_notify = get_option( 'moderation_notify' );

        /**
         * Filters whether to send the site moderator email notifications, overriding the site setting.
         *
         * @since 4.4.0
         *
         * @param bool $maybe_notify Whether to notify blog moderator.
         * @param int  $comment_ID   The id of the comment for the notification.
         */
        $maybe_notify = apply_filters( 'notify_moderator', $maybe_notify, $comment_id );

        if ( ! $maybe_notify ) {
                return true;
        }

        $comment = get_comment($comment_id);
        $post = get_post($comment->comment_post_ID);
        $user = get_userdata( $post->post_author );
        // Send to the administration and to the post author if the author can modify the comment.
        $emails = array( get_option( 'admin_email' ) );
        if ( $user && user_can( $user->ID, 'edit_comment', $comment_id ) && ! empty( $user->user_email ) ) {
                if ( 0 !== strcasecmp( $user->user_email, get_option( 'admin_email' ) ) )
                        $emails[] = $user->user_email;
        }

        $comment_author_domain = @gethostbyaddr($comment->comment_author_IP);
        $comments_waiting = $wpdb->get_var("SELECT count(comment_ID) FROM $wpdb->comments WHERE comment_approved = '0'");

        // The blogname option is escaped with esc_html on the way into the database in sanitize_option
        // we want to reverse this for the plain text arena of emails.
        $blogname = wp_specialchars_decode(get_option('blogname'), ENT_QUOTES);
        $comment_content = wp_specialchars_decode( $comment->comment_content );

        switch ( $comment->comment_type ) {
                case 'trackback':
                        $notify_message  = sprintf( __('A new trackback on the post "%s" is waiting for your approval'), $post->post_title ) . "\r\n";
                        $notify_message .= get_permalink($comment->comment_post_ID) . "\r\n\r\n";
                        /* translators: 1: website name, 2: website IP, 3: website hostname */
                        $notify_message .= sprintf( __( 'Website: %1$s (IP: %2$s, %3$s)' ), $comment->comment_author, $comment->comment_author_IP, $comment_author_domain ) . "\r\n";
                        $notify_message .= sprintf( __( 'URL: %s' ), $comment->comment_author_url ) . "\r\n";
                        $notify_message .= __('Trackback excerpt: ') . "\r\n" . $comment_content . "\r\n\r\n";
                        break;
                case 'pingback':
                        $notify_message  = sprintf( __('A new pingback on the post "%s" is waiting for your approval'), $post->post_title ) . "\r\n";
                        $notify_message .= get_permalink($comment->comment_post_ID) . "\r\n\r\n";
                        /* translators: 1: website name, 2: website IP, 3: website hostname */
                        $notify_message .= sprintf( __( 'Website: %1$s (IP: %2$s, %3$s)' ), $comment->comment_author, $comment->comment_author_IP, $comment_author_domain ) . "\r\n";
                        $notify_message .= sprintf( __( 'URL: %s' ), $comment->comment_author_url ) . "\r\n";
                        $notify_message .= __('Pingback excerpt: ') . "\r\n" . $comment_content . "\r\n\r\n";
                        break;
                default: // Comments
                        $notify_message  = sprintf( __('A new comment on the post "%s" is waiting for your approval'), $post->post_title ) . "\r\n";
                        $notify_message .= get_permalink($comment->comment_post_ID) . "\r\n\r\n";
                        $notify_message .= sprintf( __( 'Author: %1$s (IP: %2$s, %3$s)' ), $comment->comment_author, $comment->comment_author_IP, $comment_author_domain ) . "\r\n";
                        $notify_message .= sprintf( __( 'Email: %s' ), $comment->comment_author_email ) . "\r\n";
                        $notify_message .= sprintf( __( 'URL: %s' ), $comment->comment_author_url ) . "\r\n";
                        $notify_message .= sprintf( __( 'Comment: %s' ), "\r\n" . $comment_content ) . "\r\n\r\n";
                        break;
        }

        $notify_message .= sprintf( __( 'Approve it: %s' ), admin_url( "comment.php?action=approve&c={$comment_id}#wpbody-content" ) ) . "\r\n";

        if ( EMPTY_TRASH_DAYS )
                $notify_message .= sprintf( __( 'Trash it: %s' ), admin_url( "comment.php?action=trash&c={$comment_id}#wpbody-content" ) ) . "\r\n";
        else
                $notify_message .= sprintf( __( 'Delete it: %s' ), admin_url( "comment.php?action=delete&c={$comment_id}#wpbody-content" ) ) . "\r\n";

        $notify_message .= sprintf( __( 'Spam it: %s' ), admin_url( "comment.php?action=spam&c={$comment_id}#wpbody-content" ) ) . "\r\n";

        $notify_message .= sprintf( _n('Currently %s comment is waiting for approval. Please visit the moderation panel:',
                'Currently %s comments are waiting for approval. Please visit the moderation panel:', $comments_waiting), number_format_i18n($comments_waiting) ) . "\r\n";
        $notify_message .= admin_url( "edit-comments.php?comment_status=moderated#wpbody-content" ) . "\r\n";

        $subject = sprintf( __('[%1$s] Please moderate: "%2$s"'), $blogname, $post->post_title );
        $message_headers = '';

        /**
         * Filters the list of recipients for comment moderation emails.
         *
         * @since 3.7.0
         *
         * @param array $emails     List of email addresses to notify for comment moderation.
         * @param int   $comment_id Comment ID.
         */
        $emails = apply_filters( 'comment_moderation_recipients', $emails, $comment_id );

        /**
         * Filters the comment moderation email text.
         *
         * @since 1.5.2
         *
         * @param string $notify_message Text of the comment moderation email.
         * @param int    $comment_id     Comment ID.
         */
        $notify_message = apply_filters( 'comment_moderation_text', $notify_message, $comment_id );

        /**
         * Filters the comment moderation email subject.
         *
         * @since 1.5.2
         *
         * @param string $subject    Subject of the comment moderation email.
         * @param int    $comment_id Comment ID.
         */
        $subject = apply_filters( 'comment_moderation_subject', $subject, $comment_id );

        /**
         * Filters the comment moderation email headers.
         *
         * @since 2.8.0
         *
         * @param string $message_headers Headers for the comment moderation email.
         * @param int    $comment_id      Comment ID.
         */
        $message_headers = apply_filters( 'comment_moderation_headers', $message_headers, $comment_id );

        foreach ( $emails as $email ) {
                @wp_mail( $email, wp_specialchars_decode( $subject ), $notify_message, $message_headers );
        }

        return true;
}
endif;

if ( !function_exists('wp_password_change_notification') ) :
/**
 * Notify the blog admin of a user changing password, normally via email.
 *
 * @since 2.7.0
 *
 * @param WP_User $user User object.
 */
function wp_password_change_notification( $user ) {
        // send a copy of password change notification to the admin
        // but check to see if it's the admin whose password we're changing, and skip this
        if ( 0 !== strcasecmp( $user->user_email, get_option( 'admin_email' ) ) ) {
                /* translators: %s: user name */
                $message = sprintf( __( 'Password changed for user: %s' ), $user->user_login ) . "\r\n";
                // The blogname option is escaped with esc_html on the way into the database in sanitize_option
                // we want to reverse this for the plain text arena of emails.
                $blogname = wp_specialchars_decode(get_option('blogname'), ENT_QUOTES);
                /* translators: %s: site title */
                wp_mail( get_option( 'admin_email' ), sprintf( __( '[%s] Password Changed' ), $blogname ), $message );
        }
}
endif;

if ( !function_exists('wp_new_user_notification') ) :
/**
 * Email login credentials to a newly-registered user.
 *
 * A new user registration notification is also sent to admin email.
 *
 * @since 2.0.0
 * @since 4.3.0 The `$plaintext_pass` parameter was changed to `$notify`.
 * @since 4.3.1 The `$plaintext_pass` parameter was deprecated. `$notify` added as a third parameter.
 * @since 4.6.0 The `$notify` parameter accepts 'user' for sending notification only to the user created.
 *
 * @global wpdb         $wpdb      WordPress database object for queries.
 * @global PasswordHash $wp_hasher Portable PHP password hashing framework instance.
 *
 * @param int    $user_id    User ID.
 * @param null   $deprecated Not used (argument deprecated).
 * @param string $notify     Optional. Type of notification that should happen. Accepts 'admin' or an empty
 *                           string (admin only), 'user', or 'both' (admin and user). Default empty.
 */
function wp_new_user_notification( $user_id, $deprecated = null, $notify = '' ) {
        if ( $deprecated !== null ) {
                _deprecated_argument( __FUNCTION__, '4.3.1' );
        }

        global $wpdb, $wp_hasher;
        $user = get_userdata( $user_id );

        // The blogname option is escaped with esc_html on the way into the database in sanitize_option
        // we want to reverse this for the plain text arena of emails.
        $blogname = wp_specialchars_decode(get_option('blogname'), ENT_QUOTES);

        if ( 'user' !== $notify ) {
                $message  = sprintf( __( 'New user registration on your site %s:' ), $blogname ) . "\r\n\r\n";
                $message .= sprintf( __( 'Username: %s' ), $user->user_login ) . "\r\n\r\n";
                $message .= sprintf( __( 'Email: %s' ), $user->user_email ) . "\r\n";

                @wp_mail( get_option( 'admin_email' ), sprintf( __( '[%s] New User Registration' ), $blogname ), $message );
        }

        // `$deprecated was pre-4.3 `$plaintext_pass`. An empty `$plaintext_pass` didn't sent a user notifcation.
        if ( 'admin' === $notify || ( empty( $deprecated ) && empty( $notify ) ) ) {
                return;
        }

        // Generate something random for a password reset key.
        $key = wp_generate_password( 20, false );

        /** This action is documented in wp-login.php */
        do_action( 'retrieve_password_key', $user->user_login, $key );

        // Now insert the key, hashed, into the DB.
        if ( empty( $wp_hasher ) ) {
                require_once ABSPATH . WPINC . '/class-phpass.php';
                $wp_hasher = new PasswordHash( 8, true );
        }
        $hashed = time() . ':' . $wp_hasher->HashPassword( $key );
        $wpdb->update( $wpdb->users, array( 'user_activation_key' => $hashed ), array( 'user_login' => $user->user_login ) );

        $message = sprintf(__('Username: %s'), $user->user_login) . "\r\n\r\n";
        $message .= __('To set your password, visit the following address:') . "\r\n\r\n";
        $message .= '<' . network_site_url("wp-login.php?action=rp&key=$key&login=" . rawurlencode($user->user_login), 'login') . ">\r\n\r\n";

        $message .= wp_login_url() . "\r\n";

        wp_mail($user->user_email, sprintf(__('[%s] Your username and password info'), $blogname), $message);
}
endif;

if ( !function_exists('wp_nonce_tick') ) :
/**
 * Get the time-dependent variable for nonce creation.
 *
 * A nonce has a lifespan of two ticks. Nonces in their second tick may be
 * updated, e.g. by autosave.
 *
 * @since 2.5.0
 *
 * @return float Float value rounded up to the next highest integer.
 */
function wp_nonce_tick() {
        /**
         * Filters the lifespan of nonces in seconds.
         *
         * @since 2.5.0
         *
         * @param int $lifespan Lifespan of nonces in seconds. Default 86,400 seconds, or one day.
         */
        $nonce_life = apply_filters( 'nonce_life', DAY_IN_SECONDS );

        return ceil(time() / ( $nonce_life / 2 ));
}
endif;

if ( !function_exists('wp_verify_nonce') ) :
/**
 * Verify that correct nonce was used with time limit.
 *
 * The user is given an amount of time to use the token, so therefore, since the
 * UID and $action remain the same, the independent variable is the time.
 *
 * @since 2.0.3
 *
 * @param string     $nonce  Nonce that was used in the form to verify
 * @param string|int $action Should give context to what is taking place and be the same when nonce was created.
 * @return false|int False if the nonce is invalid, 1 if the nonce is valid and generated between
 *                   0-12 hours ago, 2 if the nonce is valid and generated between 12-24 hours ago.
 */
function wp_verify_nonce( $nonce, $action = -1 ) {
        $nonce = (string) $nonce;
        $user = wp_get_current_user();
        $uid = (int) $user->ID;
        if ( ! $uid ) {
                /**
                 * Filters whether the user who generated the nonce is logged out.
                 *
                 * @since 3.5.0
                 *
                 * @param int    $uid    ID of the nonce-owning user.
                 * @param string $action The nonce action.
                 */
                $uid = apply_filters( 'nonce_user_logged_out', $uid, $action );
        }

        if ( empty( $nonce ) ) {
                return false;
        }

        $token = wp_get_session_token();
        $i = wp_nonce_tick();

        // Nonce generated 0-12 hours ago
        $expected = substr( wp_hash( $i . '|' . $action . '|' . $uid . '|' . $token, 'nonce'), -12, 10 );
        if ( hash_equals( $expected, $nonce ) ) {
                return 1;
        }

        // Nonce generated 12-24 hours ago
        $expected = substr( wp_hash( ( $i - 1 ) . '|' . $action . '|' . $uid . '|' . $token, 'nonce' ), -12, 10 );
        if ( hash_equals( $expected, $nonce ) ) {
                return 2;
        }

        /**
         * Fires when nonce verification fails.
         *
         * @since 4.4.0
         *
         * @param string     $nonce  The invalid nonce.
         * @param string|int $action The nonce action.
         * @param WP_User    $user   The current user object.
         * @param string     $token  The user's session token.
         */
        do_action( 'wp_verify_nonce_failed', $nonce, $action, $user, $token );

        // Invalid nonce
        return false;
}
endif;

if ( !function_exists('wp_create_nonce') ) :
/**
 * Creates a cryptographic token tied to a specific action, user, user session,
 * and window of time.
 *
 * @since 2.0.3
 * @since 4.0.0 Session tokens were integrated with nonce creation
 *
 * @param string|int $action Scalar value to add context to the nonce.
 * @return string The token.
 */
function wp_create_nonce($action = -1) {
        $user = wp_get_current_user();
        $uid = (int) $user->ID;
        if ( ! $uid ) {
                /** This filter is documented in wp-includes/pluggable.php */
                $uid = apply_filters( 'nonce_user_logged_out', $uid, $action );
        }

        $token = wp_get_session_token();
        $i = wp_nonce_tick();

        return substr( wp_hash( $i . '|' . $action . '|' . $uid . '|' . $token, 'nonce' ), -12, 10 );
}
endif;

if ( !function_exists('wp_salt') ) :
/**
 * Get salt to add to hashes.
 *
 * Salts are created using secret keys. Secret keys are located in two places:
 * in the database and in the wp-config.php file. The secret key in the database
 * is randomly generated and will be appended to the secret keys in wp-config.php.
 *
 * The secret keys in wp-config.php should be updated to strong, random keys to maximize
 * security. Below is an example of how the secret key constants are defined.
 * Do not paste this example directly into wp-config.php. Instead, have a
 * {@link https://api.wordpress.org/secret-key/1.1/salt/ secret key created} just
 * for you.
 *
 *     define('AUTH_KEY',         ' Xakm<o xQy rw4EMsLKM-?!T+,PFF})H4lzcW57AF0U@N@< >M%G4Yt>f`z]MON');
 *     define('SECURE_AUTH_KEY',  'LzJ}op]mr|6+![P}Ak:uNdJCJZd>(Hx.-Mh#Tz)pCIU#uGEnfFz|f ;;eU%/U^O~');
 *     define('LOGGED_IN_KEY',    '|i|Ux`9<p-h$aFf(qnT:sDO:D1P^wZ$$/Ra@miTJi9G;ddp_<q}6H1)o|a +&JCM');
 *     define('NONCE_KEY',        '%:R{[P|,s.KuMltH5}cI;/k<Gx~j!f0I)m_sIyu+&NJZ)-iO>z7X>QYR0Z_XnZ@|');
 *     define('AUTH_SALT',        'eZyT)-Naw]F8CwA*VaW#q*|.)g@o}||wf~@C-YSt}(dh_r6EbI#A,y|nU2{B#JBW');
 *     define('SECURE_AUTH_SALT', '!=oLUTXh,QW=H `}`L|9/^4-3 STz},T(w}W<I`.JjPi)<Bmf1v,HpGe}T1:Xt7n');
 *     define('LOGGED_IN_SALT',   '+XSqHc;@Q*K_b|Z?NC[3H!!EONbh.n<+=uKR:>*c(u`g~EJBf#8u#R{mUEZrozmm');
 *     define('NONCE_SALT',       'h`GXHhD>SLWVfg1(1(N{;.V!MoE(SfbA_ksP@&`+AycHcAV$+?@3q+rxV{%^VyKT');
 *
 * Salting passwords helps against tools which has stored hashed values of
 * common dictionary strings. The added values makes it harder to crack.
 *
 * @since 2.5.0
 *
 * @link https://api.wordpress.org/secret-key/1.1/salt/ Create secrets for wp-config.php
 *
 * @staticvar array $cached_salts
 * @staticvar array $duplicated_keys
 *
 * @param string $scheme Authentication scheme (auth, secure_auth, logged_in, nonce)
 * @return string Salt value
 */
function wp_salt( $scheme = 'auth' ) {
        static $cached_salts = array();
        if ( isset( $cached_salts[ $scheme ] ) ) {
                /**
                 * Filters the WordPress salt.
                 *
                 * @since 2.5.0
                 *
                 * @param string $cached_salt Cached salt for the given scheme.
                 * @param string $scheme      Authentication scheme. Values include 'auth',
                 *                            'secure_auth', 'logged_in', and 'nonce'.
                 */
                return apply_filters( 'salt', $cached_salts[ $scheme ], $scheme );
        }

        static $duplicated_keys;
        if ( null === $duplicated_keys ) {
                $duplicated_keys = array( 'put your unique phrase here' => true );
                foreach ( array( 'AUTH', 'SECURE_AUTH', 'LOGGED_IN', 'NONCE', 'SECRET' ) as $first ) {
                        foreach ( array( 'KEY', 'SALT' ) as $second ) {
                                if ( ! defined( "{$first}_{$second}" ) ) {
                                        continue;
                                }
                                $value = constant( "{$first}_{$second}" );
                                $duplicated_keys[ $value ] = isset( $duplicated_keys[ $value ] );
                        }
                }
        }

        $values = array(
                'key' => '',
                'salt' => ''
        );
        if ( defined( 'SECRET_KEY' ) && SECRET_KEY && empty( $duplicated_keys[ SECRET_KEY ] ) ) {
                $values['key'] = SECRET_KEY;
        }
        if ( 'auth' == $scheme && defined( 'SECRET_SALT' ) && SECRET_SALT && empty( $duplicated_keys[ SECRET_SALT ] ) ) {
                $values['salt'] = SECRET_SALT;
        }

        if ( in_array( $scheme, array( 'auth', 'secure_auth', 'logged_in', 'nonce' ) ) ) {
                foreach ( array( 'key', 'salt' ) as $type ) {
                        $const = strtoupper( "{$scheme}_{$type}" );
                        if ( defined( $const ) && constant( $const ) && empty( $duplicated_keys[ constant( $const ) ] ) ) {
                                $values[ $type ] = constant( $const );
                        } elseif ( ! $values[ $type ] ) {
                                $values[ $type ] = get_site_option( "{$scheme}_{$type}" );
                                if ( ! $values[ $type ] ) {
                                        $values[ $type ] = wp_generate_password( 64, true, true );
                                        update_site_option( "{$scheme}_{$type}", $values[ $type ] );
                                }
                        }
                }
        } else {
                if ( ! $values['key'] ) {
                        $values['key'] = get_site_option( 'secret_key' );
                        if ( ! $values['key'] ) {
                                $values['key'] = wp_generate_password( 64, true, true );
                                update_site_option( 'secret_key', $values['key'] );
                        }
                }
                $values['salt'] = hash_hmac( 'md5', $scheme, $values['key'] );
        }

        $cached_salts[ $scheme ] = $values['key'] . $values['salt'];

        /** This filter is documented in wp-includes/pluggable.php */
        return apply_filters( 'salt', $cached_salts[ $scheme ], $scheme );
}
endif;

if ( !function_exists('wp_hash') ) :
/**
 * Get hash of given string.
 *
 * @since 2.0.3
 *
 * @param string $data   Plain text to hash
 * @param string $scheme Authentication scheme (auth, secure_auth, logged_in, nonce)
 * @return string Hash of $data
 */
function wp_hash($data, $scheme = 'auth') {
        $salt = wp_salt($scheme);

        return hash_hmac('md5', $data, $salt);
}
endif;

if ( !function_exists('wp_hash_password') ) :
/**
 * Create a hash (encrypt) of a plain text password.
 *
 * For integration with other applications, this function can be overwritten to
 * instead use the other package password checking algorithm.
 *
 * @since 2.5.0
 *
 * @global PasswordHash $wp_hasher PHPass object
 *
 * @param string $password Plain text user password to hash
 * @return string The hash string of the password
 */
function wp_hash_password($password) {
        global $wp_hasher;

        if ( empty($wp_hasher) ) {
                require_once( ABSPATH . WPINC . '/class-phpass.php');
                // By default, use the portable hash from phpass
                $wp_hasher = new PasswordHash(8, true);
        }

        return $wp_hasher->HashPassword( trim( $password ) );
}
endif;

if ( !function_exists('wp_check_password') ) :
/**
 * Checks the plaintext password against the encrypted Password.
 *
 * Maintains compatibility between old version and the new cookie authentication
 * protocol using PHPass library. The $hash parameter is the encrypted password
 * and the function compares the plain text password when encrypted similarly
 * against the already encrypted password to see if they match.
 *
 * For integration with other applications, this function can be overwritten to
 * instead use the other package password checking algorithm.
 *
 * @since 2.5.0
 *
 * @global PasswordHash $wp_hasher PHPass object used for checking the password
 *      against the $hash + $password
 * @uses PasswordHash::CheckPassword
 *
 * @param string     $password Plaintext user's password
 * @param string     $hash     Hash of the user's password to check against.
 * @param string|int $user_id  Optional. User ID.
 * @return bool False, if the $password does not match the hashed password
 */
function wp_check_password($password, $hash, $user_id = '') {
        global $wp_hasher;

        // If the hash is still md5...
        if ( strlen($hash) <= 32 ) {
                $check = hash_equals( $hash, md5( $password ) );
                if ( $check && $user_id ) {
                        // Rehash using new hash.
                        wp_set_password($password, $user_id);
                        $hash = wp_hash_password($password);
                }

                /**
                 * Filters whether the plaintext password matches the encrypted password.
                 *
                 * @since 2.5.0
                 *
                 * @param bool       $check    Whether the passwords match.
                 * @param string     $password The plaintext password.
                 * @param string     $hash     The hashed password.
                 * @param string|int $user_id  User ID. Can be empty.
                 */
                return apply_filters( 'check_password', $check, $password, $hash, $user_id );
        }

        // If the stored hash is longer than an MD5, presume the
        // new style phpass portable hash.
        if ( empty($wp_hasher) ) {
                require_once( ABSPATH . WPINC . '/class-phpass.php');
                // By default, use the portable hash from phpass
                $wp_hasher = new PasswordHash(8, true);
        }

        $check = $wp_hasher->CheckPassword($password, $hash);

        /** This filter is documented in wp-includes/pluggable.php */
        return apply_filters( 'check_password', $check, $password, $hash, $user_id );
}
endif;

if ( !function_exists('wp_generate_password') ) :
/**
 * Generates a random password drawn from the defined set of characters.
 *
 * @since 2.5.0
 *
 * @param int  $length              Optional. The length of password to generate. Default 12.
 * @param bool $special_chars       Optional. Whether to include standard special characters.
 *                                  Default true.
 * @param bool $extra_special_chars Optional. Whether to include other special characters.
 *                                  Used when generating secret keys and salts. Default false.
 * @return string The random password.
 */
function wp_generate_password( $length = 12, $special_chars = true, $extra_special_chars = false ) {
        $chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';
        if ( $special_chars )
                $chars .= '!@#$%^&*()';
        if ( $extra_special_chars )
                $chars .= '-_ []{}<>~`+=,.;:/?|';

        $password = '';
        for ( $i = 0; $i < $length; $i++ ) {
                $password .= substr($chars, wp_rand(0, strlen($chars) - 1), 1);
        }

        /**
         * Filters the randomly-generated password.
         *
         * @since 3.0.0
         *
         * @param string $password The generated password.
         */
        return apply_filters( 'random_password', $password );
}
endif;

if ( !function_exists('wp_rand') ) :
/**
 * Generates a random number
 *
 * @since 2.6.2
 * @since 4.4.0 Uses PHP7 random_int() or the random_compat library if available.
 *
 * @global string $rnd_value
 * @staticvar string $seed
 * @staticvar bool $external_rand_source_available
 *
 * @param int $min Lower limit for the generated number
 * @param int $max Upper limit for the generated number
 * @return int A random number between min and max
 */
function wp_rand( $min = 0, $max = 0 ) {
        global $rnd_value;

        // Some misconfigured 32bit environments (Entropy PHP, for example) truncate integers larger than PHP_INT_MAX to PHP_INT_MAX rather than overflowing them to floats.
        $max_random_number = 3000000000 === 2147483647 ? (float) "4294967295" : 4294967295; // 4294967295 = 0xffffffff

        // We only handle Ints, floats are truncated to their integer value.
        $min = (int) $min;
        $max = (int) $max;

        // Use PHP's CSPRNG, or a compatible method
        static $use_random_int_functionality = true;
        if ( $use_random_int_functionality ) {
                try {
                        $_max = ( 0 != $max ) ? $max : $max_random_number;
                        // wp_rand() can accept arguments in either order, PHP cannot.
                        $_max = max( $min, $_max );
                        $_min = min( $min, $_max );
                        $val = random_int( $_min, $_max );
                        if ( false !== $val ) {
                                return absint( $val );
                        } else {
                                $use_random_int_functionality = false;
                        }
                } catch ( Error $e ) {
                        $use_random_int_functionality = false;
                } catch ( Exception $e ) {
                        $use_random_int_functionality = false;
                }
        }

        // Reset $rnd_value after 14 uses
        // 32(md5) + 40(sha1) + 40(sha1) / 8 = 14 random numbers from $rnd_value
        if ( strlen($rnd_value) < 8 ) {
                if ( defined( 'WP_SETUP_CONFIG' ) )
                        static $seed = '';
                else
                        $seed = get_transient('random_seed');
                $rnd_value = md5( uniqid(microtime() . mt_rand(), true ) . $seed );
                $rnd_value .= sha1($rnd_value);
                $rnd_value .= sha1($rnd_value . $seed);
                $seed = md5($seed . $rnd_value);
                if ( ! defined( 'WP_SETUP_CONFIG' ) && ! defined( 'WP_INSTALLING' ) ) {
                        set_transient( 'random_seed', $seed );
                }
        }

        // Take the first 8 digits for our value
        $value = substr($rnd_value, 0, 8);

        // Strip the first eight, leaving the remainder for the next call to wp_rand().
        $rnd_value = substr($rnd_value, 8);

        $value = abs(hexdec($value));

        // Reduce the value to be within the min - max range
        if ( $max != 0 )
                $value = $min + ( $max - $min + 1 ) * $value / ( $max_random_number + 1 );

        return abs(intval($value));
}
endif;

if ( !function_exists('wp_set_password') ) :
/**
 * Updates the user's password with a new encrypted one.
 *
 * For integration with other applications, this function can be overwritten to
 * instead use the other package password checking algorithm.
 *
 * Please note: This function should be used sparingly and is really only meant for single-time
 * application. Leveraging this improperly in a plugin or theme could result in an endless loop
 * of password resets if precautions are not taken to ensure it does not execute on every page load.
 *
 * @since 2.5.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param string $password The plaintext new user password
 * @param int    $user_id  User ID
 */
function wp_set_password( $password, $user_id ) {
        global $wpdb;

        $hash = wp_hash_password( $password );
        $wpdb->update($wpdb->users, array('user_pass' => $hash, 'user_activation_key' => ''), array('ID' => $user_id) );

        wp_cache_delete($user_id, 'users');
}
endif;

if ( !function_exists( 'get_avatar' ) ) :
/**
 * Retrieve the avatar `<img>` tag for a user, email address, MD5 hash, comment, or post.
 *
 * @since 2.5.0
 * @since 4.2.0 Optional `$args` parameter added.
 *
 * @param mixed $id_or_email The Gravatar to retrieve. Accepts a user_id, gravatar md5 hash,
 *                           user email, WP_User object, WP_Post object, or WP_Comment object.
 * @param int    $size       Optional. Height and width of the avatar image file in pixels. Default 96.
 * @param string $default    Optional. URL for the default image or a default type. Accepts '404'
 *                           (return a 404 instead of a default image), 'retro' (8bit), 'monsterid'
 *                           (monster), 'wavatar' (cartoon face), 'indenticon' (the "quilt"),
 *                           'mystery', 'mm', or 'mysteryman' (The Oyster Man), 'blank' (transparent GIF),
 *                           or 'gravatar_default' (the Gravatar logo). Default is the value of the
 *                           'avatar_default' option, with a fallback of 'mystery'.
 * @param string $alt        Optional. Alternative text to use in &lt;img&gt; tag. Default empty.
 * @param array  $args       {
 *     Optional. Extra arguments to retrieve the avatar.
 *
 *     @type int          $height        Display height of the avatar in pixels. Defaults to $size.
 *     @type int          $width         Display width of the avatar in pixels. Defaults to $size.
 *     @type bool         $force_default Whether to always show the default image, never the Gravatar. Default false.
 *     @type string       $rating        What rating to display avatars up to. Accepts 'G', 'PG', 'R', 'X', and are
 *                                       judged in that order. Default is the value of the 'avatar_rating' option.
 *     @type string       $scheme        URL scheme to use. See set_url_scheme() for accepted values.
 *                                       Default null.
 *     @type array|string $class         Array or string of additional classes to add to the &lt;img&gt; element.
 *                                       Default null.
 *     @type bool         $force_display Whether to always show the avatar - ignores the show_avatars option.
 *                                       Default false.
 *     @type string       $extra_attr    HTML attributes to insert in the IMG element. Is not sanitized. Default empty.
 * }
 * @return false|string `<img>` tag for the user's avatar. False on failure.
 */
function get_avatar( $id_or_email, $size = 96, $default = '', $alt = '', $args = null ) {
        $defaults = array(
                // get_avatar_data() args.
                'size'          => 96,
                'height'        => null,
                'width'         => null,
                'default'       => get_option( 'avatar_default', 'mystery' ),
                'force_default' => false,
                'rating'        => get_option( 'avatar_rating' ),
                'scheme'        => null,
                'alt'           => '',
                'class'         => null,
                'force_display' => false,
                'extra_attr'    => '',
        );

        if ( empty( $args ) ) {
                $args = array();
        }

        $args['size']    = (int) $size;
        $args['default'] = $default;
        $args['alt']     = $alt;

        $args = wp_parse_args( $args, $defaults );

        if ( empty( $args['height'] ) ) {
                $args['height'] = $args['size'];
        }
        if ( empty( $args['width'] ) ) {
                $args['width'] = $args['size'];
        }

        if ( is_object( $id_or_email ) && isset( $id_or_email->comment_ID ) ) {
                $id_or_email = get_comment( $id_or_email );
        }

        /**
         * Filters whether to retrieve the avatar URL early.
         *
         * Passing a non-null value will effectively short-circuit get_avatar(), passing
         * the value through the {@see 'get_avatar'} filter and returning early.
         *
         * @since 4.2.0
         *
         * @param string $avatar      HTML for the user's avatar. Default null.
         * @param mixed  $id_or_email The Gravatar to retrieve. Accepts a user_id, gravatar md5 hash,
         *                            user email, WP_User object, WP_Post object, or WP_Comment object.
         * @param array  $args        Arguments passed to get_avatar_url(), after processing.
         */
        $avatar = apply_filters( 'pre_get_avatar', null, $id_or_email, $args );

        if ( ! is_null( $avatar ) ) {
                /** This filter is documented in wp-includes/pluggable.php */
                return apply_filters( 'get_avatar', $avatar, $id_or_email, $args['size'], $args['default'], $args['alt'], $args );
        }

        if ( ! $args['force_display'] && ! get_option( 'show_avatars' ) ) {
                return false;
        }

        $url2x = get_avatar_url( $id_or_email, array_merge( $args, array( 'size' => $args['size'] * 2 ) ) );

        $args = get_avatar_data( $id_or_email, $args );

        $url = $args['url'];

        if ( ! $url || is_wp_error( $url ) ) {
                return false;
        }

        $class = array( 'avatar', 'avatar-' . (int) $args['size'], 'photo' );

        if ( ! $args['found_avatar'] || $args['force_default'] ) {
                $class[] = 'avatar-default';
        }

        if ( $args['class'] ) {
                if ( is_array( $args['class'] ) ) {
                        $class = array_merge( $class, $args['class'] );
                } else {
                        $class[] = $args['class'];
                }
        }

        $avatar = sprintf(
                "<img alt='%s' src='%s' srcset='%s' class='%s' height='%d' width='%d' %s/>",
                esc_attr( $args['alt'] ),
                esc_url( $url ),
                esc_attr( "$url2x 2x" ),
                esc_attr( join( ' ', $class ) ),
                (int) $args['height'],
                (int) $args['width'],
                $args['extra_attr']
        );

        /**
         * Filters the avatar to retrieve.
         *
         * @since 2.5.0
         * @since 4.2.0 The `$args` parameter was added.
         *
         * @param string $avatar      &lt;img&gt; tag for the user's avatar.
         * @param mixed  $id_or_email The Gravatar to retrieve. Accepts a user_id, gravatar md5 hash,
         *                            user email, WP_User object, WP_Post object, or WP_Comment object.
         * @param int    $size        Square avatar width and height in pixels to retrieve.
         * @param string $alt         Alternative text to use in the avatar image tag.
         *                                       Default empty.
         * @param array  $args        Arguments passed to get_avatar_data(), after processing.
         */
        return apply_filters( 'get_avatar', $avatar, $id_or_email, $args['size'], $args['default'], $args['alt'], $args );
}
endif;

if ( !function_exists( 'wp_text_diff' ) ) :
/**
 * Displays a human readable HTML representation of the difference between two strings.
 *
 * The Diff is available for getting the changes between versions. The output is
 * HTML, so the primary use is for displaying the changes. If the two strings
 * are equivalent, then an empty string will be returned.
 *
 * The arguments supported and can be changed are listed below.
 *
 * 'title' : Default is an empty string. Titles the diff in a manner compatible
 *              with the output.
 * 'title_left' : Default is an empty string. Change the HTML to the left of the
 *              title.
 * 'title_right' : Default is an empty string. Change the HTML to the right of
 *              the title.
 *
 * @since 2.6.0
 *
 * @see wp_parse_args() Used to change defaults to user defined settings.
 * @uses Text_Diff
 * @uses WP_Text_Diff_Renderer_Table
 *
 * @param string       $left_string  "old" (left) version of string
 * @param string       $right_string "new" (right) version of string
 * @param string|array $args         Optional. Change 'title', 'title_left', and 'title_right' defaults.
 * @return string Empty string if strings are equivalent or HTML with differences.
 */
function wp_text_diff( $left_string, $right_string, $args = null ) {
        $defaults = array( 'title' => '', 'title_left' => '', 'title_right' => '' );
        $args = wp_parse_args( $args, $defaults );

        if ( ! class_exists( 'WP_Text_Diff_Renderer_Table', false ) )
                require( ABSPATH . WPINC . '/wp-diff.php' );

        $left_string  = normalize_whitespace($left_string);
        $right_string = normalize_whitespace($right_string);

        $left_lines  = explode("\n", $left_string);
        $right_lines = explode("\n", $right_string);
        $text_diff = new Text_Diff($left_lines, $right_lines);
        $renderer  = new WP_Text_Diff_Renderer_Table( $args );
        $diff = $renderer->render($text_diff);

        if ( !$diff )
                return '';

        $r  = "<table class='diff'>\n";

        if ( ! empty( $args[ 'show_split_view' ] ) ) {
                $r .= "<col class='content diffsplit left' /><col class='content diffsplit middle' /><col class='content diffsplit right' />";
        } else {
                $r .= "<col class='content' />";
        }

        if ( $args['title'] || $args['title_left'] || $args['title_right'] )
                $r .= "<thead>";
        if ( $args['title'] )
                $r .= "<tr class='diff-title'><th colspan='4'>$args[title]</th></tr>\n";
        if ( $args['title_left'] || $args['title_right'] ) {
                $r .= "<tr class='diff-sub-title'>\n";
                $r .= "\t<td></td><th>$args[title_left]</th>\n";
                $r .= "\t<td></td><th>$args[title_right]</th>\n";
                $r .= "</tr>\n";
        }
        if ( $args['title'] || $args['title_left'] || $args['title_right'] )
                $r .= "</thead>\n";

        $r .= "<tbody>\n$diff\n</tbody>\n";
        $r .= "</table>";

        return $r;
}
endif;