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<?php
/**
 * WordPress environment setup class.
 *
 * @package WordPress
 * @since 2.0.0
 */
class WP {
   
/**
     * Public query variables.
     *
     * Long list of public query variables.
     *
     * @since 2.0.0
     * @var string[]
     */
   
public $public_query_vars = array( 'm', 'p', 'posts', 'w', 'cat', 'withcomments', 'withoutcomments', 's', 'search', 'exact', 'sentence', 'calendar', 'page', 'paged', 'more', 'tb', 'pb', 'author', 'order', 'orderby', 'year', 'monthnum', 'day', 'hour', 'minute', 'second', 'name', 'category_name', 'tag', 'feed', 'author_name', 'pagename', 'page_id', 'error', 'attachment', 'attachment_id', 'subpost', 'subpost_id', 'preview', 'robots', 'favicon', 'taxonomy', 'term', 'cpage', 'post_type', 'embed' );

   
/**
     * Private query variables.
     *
     * Long list of private query variables.
     *
     * @since 2.0.0
     * @var string[]
     */
   
public $private_query_vars = array( 'offset', 'posts_per_page', 'posts_per_archive_page', 'showposts', 'nopaging', 'post_type', 'post_status', 'category__in', 'category__not_in', 'category__and', 'tag__in', 'tag__not_in', 'tag__and', 'tag_slug__in', 'tag_slug__and', 'tag_id', 'post_mime_type', 'perm', 'comments_per_page', 'post__in', 'post__not_in', 'post_parent', 'post_parent__in', 'post_parent__not_in', 'title', 'fields' );

   
/**
     * Extra query variables set by the user.
     *
     * @since 2.1.0
     * @var array
     */
   
public $extra_query_vars = array();

   
/**
     * Query variables for setting up the WordPress Query Loop.
     *
     * @since 2.0.0
     * @var array
     */
   
public $query_vars = array();

   
/**
     * String parsed to set the query variables.
     *
     * @since 2.0.0
     * @var string
     */
   
public $query_string = '';

   
/**
     * The request path, e.g. 2015/05/06.
     *
     * @since 2.0.0
     * @var string
     */
   
public $request = '';

   
/**
     * Rewrite rule the request matched.
     *
     * @since 2.0.0
     * @var string
     */
   
public $matched_rule = '';

   
/**
     * Rewrite query the request matched.
     *
     * @since 2.0.0
     * @var string
     */
   
public $matched_query = '';

   
/**
     * Whether already did the permalink.
     *
     * @since 2.0.0
     * @var bool
     */
   
public $did_permalink = false;

   
/**
     * Adds a query variable to the list of public query variables.
     *
     * @since 2.1.0
     *
     * @param string $qv Query variable name.
     */
   
public function add_query_var( $qv ) {
        if ( !
in_array( $qv, $this->public_query_vars, true ) ) {
           
$this->public_query_vars[] = $qv;
        }
    }

   
/**
     * Removes a query variable from a list of public query variables.
     *
     * @since 4.5.0
     *
     * @param string $name Query variable name.
     */
   
public function remove_query_var( $name ) {
       
$this->public_query_vars = array_diff( $this->public_query_vars, array( $name ) );
    }

   
/**
     * Sets the value of a query variable.
     *
     * @since 2.3.0
     *
     * @param string $key   Query variable name.
     * @param mixed  $value Query variable value.
     */
   
public function set_query_var( $key, $value ) {
       
$this->query_vars[ $key ] = $value;
    }

   
/**
     * Parses the request to find the correct WordPress query.
     *
     * Sets up the query variables based on the request. There are also many
     * filters and actions that can be used to further manipulate the result.
     *
     * @since 2.0.0
     * @since 6.0.0 A return value was added.
     *
     * @global WP_Rewrite $wp_rewrite WordPress rewrite component.
     *
     * @param array|string $extra_query_vars Set the extra query variables.
     * @return bool Whether the request was parsed.
     */
   
public function parse_request( $extra_query_vars = '' ) {
        global
$wp_rewrite;

       
/**
         * Filters whether to parse the request.
         *
         * @since 3.5.0
         *
         * @param bool         $bool             Whether or not to parse the request. Default true.
         * @param WP           $wp               Current WordPress environment instance.
         * @param array|string $extra_query_vars Extra passed query variables.
         */
       
if ( ! apply_filters( 'do_parse_request', true, $this, $extra_query_vars ) ) {
            return
false;
        }

       
$this->query_vars     = array();
       
$post_type_query_vars = array();

        if (
is_array( $extra_query_vars ) ) {
           
$this->extra_query_vars = & $extra_query_vars;
        } elseif ( ! empty(
$extra_query_vars ) ) {
           
parse_str( $extra_query_vars, $this->extra_query_vars );
        }
       
// Process PATH_INFO, REQUEST_URI, and 404 for permalinks.

        // Fetch the rewrite rules.
       
$rewrite = $wp_rewrite->wp_rewrite_rules();

        if ( ! empty(
$rewrite ) ) {
           
// If we match a rewrite rule, this will be cleared.
           
$error               = '404';
           
$this->did_permalink = true;

           
$pathinfo         = isset( $_SERVER['PATH_INFO'] ) ? $_SERVER['PATH_INFO'] : '';
            list(
$pathinfo ) = explode( '?', $pathinfo );
           
$pathinfo         = str_replace( '%', '%25', $pathinfo );

            list(
$req_uri ) = explode( '?', $_SERVER['REQUEST_URI'] );
           
$self            = $_SERVER['PHP_SELF'];

           
$home_path       = parse_url( home_url(), PHP_URL_PATH );
           
$home_path_regex = '';
            if (
is_string( $home_path ) && '' !== $home_path ) {
               
$home_path       = trim( $home_path, '/' );
               
$home_path_regex = sprintf( '|^%s|i', preg_quote( $home_path, '|' ) );
            }

           
/*
             * Trim path info from the end and the leading home path from the front.
             * For path info requests, this leaves us with the requesting filename, if any.
             * For 404 requests, this leaves us with the requested permalink.
             */
           
$req_uri  = str_replace( $pathinfo, '', $req_uri );
           
$req_uri  = trim( $req_uri, '/' );
           
$pathinfo = trim( $pathinfo, '/' );
           
$self     = trim( $self, '/' );

            if ( ! empty(
$home_path_regex ) ) {
               
$req_uri  = preg_replace( $home_path_regex, '', $req_uri );
               
$req_uri  = trim( $req_uri, '/' );
               
$pathinfo = preg_replace( $home_path_regex, '', $pathinfo );
               
$pathinfo = trim( $pathinfo, '/' );
               
$self     = preg_replace( $home_path_regex, '', $self );
               
$self     = trim( $self, '/' );
            }

           
// The requested permalink is in $pathinfo for path info requests and
            // $req_uri for other requests.
           
if ( ! empty( $pathinfo ) && ! preg_match( '|^.*' . $wp_rewrite->index . '$|', $pathinfo ) ) {
               
$requested_path = $pathinfo;
            } else {
               
// If the request uri is the index, blank it out so that we don't try to match it against a rule.
               
if ( $req_uri == $wp_rewrite->index ) {
                   
$req_uri = '';
                }
               
$requested_path = $req_uri;
            }
           
$requested_file = $req_uri;

           
$this->request = $requested_path;

           
// Look for matches.
           
$request_match = $requested_path;
            if ( empty(
$request_match ) ) {
               
// An empty request could only match against ^$ regex.
               
if ( isset( $rewrite['$'] ) ) {
                   
$this->matched_rule = '$';
                   
$query              = $rewrite['$'];
                   
$matches            = array( '' );
                }
            } else {
                foreach ( (array)
$rewrite as $match => $query ) {
                   
// If the requested file is the anchor of the match, prepend it to the path info.
                   
if ( ! empty( $requested_file ) && strpos( $match, $requested_file ) === 0 && $requested_file != $requested_path ) {
                       
$request_match = $requested_file . '/' . $requested_path;
                    }

                    if (
preg_match( "#^$match#", $request_match, $matches ) ||
                       
preg_match( "#^$match#", urldecode( $request_match ), $matches ) ) {

                        if (
$wp_rewrite->use_verbose_page_rules && preg_match( '/pagename=\$matches\[([0-9]+)\]/', $query, $varmatch ) ) {
                           
// This is a verbose page match, let's check to be sure about it.
                           
$page = get_page_by_path( $matches[ $varmatch[1] ] );
                            if ( !
$page ) {
                                continue;
                            }

                           
$post_status_obj = get_post_status_object( $page->post_status );
                            if ( !
$post_status_obj->public && ! $post_status_obj->protected
                               
&& ! $post_status_obj->private && $post_status_obj->exclude_from_search ) {
                                continue;
                            }
                        }

                       
// Got a match.
                       
$this->matched_rule = $match;
                        break;
                    }
                }
            }

            if ( ! empty(
$this->matched_rule ) ) {
               
// Trim the query of everything up to the '?'.
               
$query = preg_replace( '!^.+\?!', '', $query );

               
// Substitute the substring matches into the query.
               
$query = addslashes( WP_MatchesMapRegex::apply( $query, $matches ) );

               
$this->matched_query = $query;

               
// Parse the query.
               
parse_str( $query, $perma_query_vars );

               
// If we're processing a 404 request, clear the error var since we found something.
               
if ( '404' == $error ) {
                    unset(
$error, $_GET['error'] );
                }
            }

           
// If req_uri is empty or if it is a request for ourself, unset error.
           
if ( empty( $requested_path ) || $requested_file == $self || strpos( $_SERVER['PHP_SELF'], 'wp-admin/' ) !== false ) {
                unset(
$error, $_GET['error'] );

                if ( isset(
$perma_query_vars ) && strpos( $_SERVER['PHP_SELF'], 'wp-admin/' ) !== false ) {
                    unset(
$perma_query_vars );
                }

               
$this->did_permalink = false;
            }
        }

       
/**
         * Filters the query variables allowed before processing.
         *
         * Allows (publicly allowed) query vars to be added, removed, or changed prior
         * to executing the query. Needed to allow custom rewrite rules using your own arguments
         * to work, or any other custom query variables you want to be publicly available.
         *
         * @since 1.5.0
         *
         * @param string[] $public_query_vars The array of allowed query variable names.
         */
       
$this->public_query_vars = apply_filters( 'query_vars', $this->public_query_vars );

        foreach (
get_post_types( array(), 'objects' ) as $post_type => $t ) {
            if (
is_post_type_viewable( $t ) && $t->query_var ) {
               
$post_type_query_vars[ $t->query_var ] = $post_type;
            }
        }

        foreach (
$this->public_query_vars as $wpvar ) {
            if ( isset(
$this->extra_query_vars[ $wpvar ] ) ) {
               
$this->query_vars[ $wpvar ] = $this->extra_query_vars[ $wpvar ];
            } elseif ( isset(
$_GET[ $wpvar ] ) && isset( $_POST[ $wpvar ] ) && $_GET[ $wpvar ] !== $_POST[ $wpvar ] ) {
               
wp_die( __( 'A variable mismatch has been detected.' ), __( 'Sorry, you are not allowed to view this item.' ), 400 );
            } elseif ( isset(
$_POST[ $wpvar ] ) ) {
               
$this->query_vars[ $wpvar ] = $_POST[ $wpvar ];
            } elseif ( isset(
$_GET[ $wpvar ] ) ) {
               
$this->query_vars[ $wpvar ] = $_GET[ $wpvar ];
            } elseif ( isset(
$perma_query_vars[ $wpvar ] ) ) {
               
$this->query_vars[ $wpvar ] = $perma_query_vars[ $wpvar ];
            }

            if ( ! empty(
$this->query_vars[ $wpvar ] ) ) {
                if ( !
is_array( $this->query_vars[ $wpvar ] ) ) {
                   
$this->query_vars[ $wpvar ] = (string) $this->query_vars[ $wpvar ];
                } else {
                    foreach (
$this->query_vars[ $wpvar ] as $vkey => $v ) {
                        if (
is_scalar( $v ) ) {
                           
$this->query_vars[ $wpvar ][ $vkey ] = (string) $v;
                        }
                    }
                }

                if ( isset(
$post_type_query_vars[ $wpvar ] ) ) {
                   
$this->query_vars['post_type'] = $post_type_query_vars[ $wpvar ];
                   
$this->query_vars['name']      = $this->query_vars[ $wpvar ];
                }
            }
        }

       
// Convert urldecoded spaces back into '+'.
       
foreach ( get_taxonomies( array(), 'objects' ) as $taxonomy => $t ) {
            if (
$t->query_var && isset( $this->query_vars[ $t->query_var ] ) ) {
               
$this->query_vars[ $t->query_var ] = str_replace( ' ', '+', $this->query_vars[ $t->query_var ] );
            }
        }

       
// Don't allow non-publicly queryable taxonomies to be queried from the front end.
       
if ( ! is_admin() ) {
            foreach (
get_taxonomies( array( 'publicly_queryable' => false ), 'objects' ) as $taxonomy => $t ) {
               
/*
                 * Disallow when set to the 'taxonomy' query var.
                 * Non-publicly queryable taxonomies cannot register custom query vars. See register_taxonomy().
                 */
               
if ( isset( $this->query_vars['taxonomy'] ) && $taxonomy === $this->query_vars['taxonomy'] ) {
                    unset(
$this->query_vars['taxonomy'], $this->query_vars['term'] );
                }
            }
        }

       
// Limit publicly queried post_types to those that are 'publicly_queryable'.
       
if ( isset( $this->query_vars['post_type'] ) ) {
           
$queryable_post_types = get_post_types( array( 'publicly_queryable' => true ) );
            if ( !
is_array( $this->query_vars['post_type'] ) ) {
                if ( !
in_array( $this->query_vars['post_type'], $queryable_post_types, true ) ) {
                    unset(
$this->query_vars['post_type'] );
                }
            } else {
               
$this->query_vars['post_type'] = array_intersect( $this->query_vars['post_type'], $queryable_post_types );
            }
        }

       
// Resolve conflicts between posts with numeric slugs and date archive queries.
       
$this->query_vars = wp_resolve_numeric_slug_conflicts( $this->query_vars );

        foreach ( (array)
$this->private_query_vars as $var ) {
            if ( isset(
$this->extra_query_vars[ $var ] ) ) {
               
$this->query_vars[ $var ] = $this->extra_query_vars[ $var ];
            }
        }

        if ( isset(
$error ) ) {
           
$this->query_vars['error'] = $error;
        }

       
/**
         * Filters the array of parsed query variables.
         *
         * @since 2.1.0
         *
         * @param array $query_vars The array of requested query variables.
         */
       
$this->query_vars = apply_filters( 'request', $this->query_vars );

       
/**
         * Fires once all query variables for the current request have been parsed.
         *
         * @since 2.1.0
         *
         * @param WP $wp Current WordPress environment instance (passed by reference).
         */
       
do_action_ref_array( 'parse_request', array( &$this ) );

        return
true;
    }

   
/**
     * Sends additional HTTP headers for caching, content type, etc.
     *
     * Sets the Content-Type header. Sets the 'error' status (if passed) and optionally exits.
     * If showing a feed, it will also send Last-Modified, ETag, and 304 status if needed.
     *
     * @since 2.0.0
     * @since 4.4.0 `X-Pingback` header is added conditionally after posts have been queried in handle_404().
     */
   
public function send_headers() {
       
$headers       = array();
       
$status        = null;
       
$exit_required = false;
       
$date_format   = 'D, d M Y H:i:s';

        if (
is_user_logged_in() ) {
           
$headers = array_merge( $headers, wp_get_nocache_headers() );
        } elseif ( ! empty(
$_GET['unapproved'] ) && ! empty( $_GET['moderation-hash'] ) ) {
           
// Unmoderated comments are only visible for 10 minutes via the moderation hash.
           
$expires = 10 * MINUTE_IN_SECONDS;

           
$headers['Expires']       = gmdate( $date_format, time() + $expires );
           
$headers['Cache-Control'] = sprintf(
               
'max-age=%d, must-revalidate',
               
$expires
           
);
        }
        if ( ! empty(
$this->query_vars['error'] ) ) {
           
$status = (int) $this->query_vars['error'];
            if (
404 === $status ) {
                if ( !
is_user_logged_in() ) {
                   
$headers = array_merge( $headers, wp_get_nocache_headers() );
                }
               
$headers['Content-Type'] = get_option( 'html_type' ) . '; charset=' . get_option( 'blog_charset' );
            } elseif (
in_array( $status, array( 403, 500, 502, 503 ), true ) ) {
               
$exit_required = true;
            }
        } elseif ( empty(
$this->query_vars['feed'] ) ) {
           
$headers['Content-Type'] = get_option( 'html_type' ) . '; charset=' . get_option( 'blog_charset' );
        } else {
           
// Set the correct content type for feeds.
           
$type = $this->query_vars['feed'];
            if (
'feed' === $this->query_vars['feed'] ) {
               
$type = get_default_feed();
            }
           
$headers['Content-Type'] = feed_content_type( $type ) . '; charset=' . get_option( 'blog_charset' );

           
// We're showing a feed, so WP is indeed the only thing that last changed.
           
if ( ! empty( $this->query_vars['withcomments'] )
                ||
false !== strpos( $this->query_vars['feed'], 'comments-' )
                || ( empty(
$this->query_vars['withoutcomments'] )
                    && ( ! empty(
$this->query_vars['p'] )
                        || ! empty(
$this->query_vars['name'] )
                        || ! empty(
$this->query_vars['page_id'] )
                        || ! empty(
$this->query_vars['pagename'] )
                        || ! empty(
$this->query_vars['attachment'] )
                        || ! empty(
$this->query_vars['attachment_id'] )
                    )
                )
            ) {
               
$wp_last_modified_post    = mysql2date( $date_format, get_lastpostmodified( 'GMT' ), false );
               
$wp_last_modified_comment = mysql2date( $date_format, get_lastcommentmodified( 'GMT' ), false );
                if (
strtotime( $wp_last_modified_post ) > strtotime( $wp_last_modified_comment ) ) {
                   
$wp_last_modified = $wp_last_modified_post;
                } else {
                   
$wp_last_modified = $wp_last_modified_comment;
                }
            } else {
               
$wp_last_modified = mysql2date( $date_format, get_lastpostmodified( 'GMT' ), false );
            }

            if ( !
$wp_last_modified ) {
               
$wp_last_modified = gmdate( $date_format );
            }

           
$wp_last_modified .= ' GMT';

           
$wp_etag                  = '"' . md5( $wp_last_modified ) . '"';
           
$headers['Last-Modified'] = $wp_last_modified;
           
$headers['ETag']          = $wp_etag;

           
// Support for conditional GET.
           
if ( isset( $_SERVER['HTTP_IF_NONE_MATCH'] ) ) {
               
$client_etag = wp_unslash( $_SERVER['HTTP_IF_NONE_MATCH'] );
            } else {
               
$client_etag = false;
            }

           
$client_last_modified = empty( $_SERVER['HTTP_IF_MODIFIED_SINCE'] ) ? '' : trim( $_SERVER['HTTP_IF_MODIFIED_SINCE'] );
           
// If string is empty, return 0. If not, attempt to parse into a timestamp.
           
$client_modified_timestamp = $client_last_modified ? strtotime( $client_last_modified ) : 0;

           
// Make a timestamp for our most recent modification..
           
$wp_modified_timestamp = strtotime( $wp_last_modified );

            if ( (
$client_last_modified && $client_etag ) ?
                    ( (
$client_modified_timestamp >= $wp_modified_timestamp ) && ( $client_etag == $wp_etag ) ) :
                    ( (
$client_modified_timestamp >= $wp_modified_timestamp ) || ( $client_etag == $wp_etag ) ) ) {
               
$status        = 304;
               
$exit_required = true;
            }
        }

       
/**
         * Filters the HTTP headers before they're sent to the browser.
         *
         * @since 2.8.0
         *
         * @param string[] $headers Associative array of headers to be sent.
         * @param WP       $wp      Current WordPress environment instance.
         */
       
$headers = apply_filters( 'wp_headers', $headers, $this );

        if ( ! empty(
$status ) ) {
           
status_header( $status );
        }

       
// If Last-Modified is set to false, it should not be sent (no-cache situation).
       
if ( isset( $headers['Last-Modified'] ) && false === $headers['Last-Modified'] ) {
            unset(
$headers['Last-Modified'] );

            if ( !
headers_sent() ) {
               
header_remove( 'Last-Modified' );
            }
        }

        if ( !
headers_sent() ) {
            foreach ( (array)
$headers as $name => $field_value ) {
               
header( "{$name}: {$field_value}" );
            }
        }

        if (
$exit_required ) {
            exit;
        }

       
/**
         * Fires once the requested HTTP headers for caching, content type, etc. have been sent.
         *
         * @since 2.1.0
         *
         * @param WP $wp Current WordPress environment instance (passed by reference).
         */
       
do_action_ref_array( 'send_headers', array( &$this ) );
    }

   
/**
     * Sets the query string property based off of the query variable property.
     *
     * The {@see 'query_string'} filter is deprecated, but still works. Plugins should
     * use the {@see 'request'} filter instead.
     *
     * @since 2.0.0
     */
   
public function build_query_string() {
       
$this->query_string = '';
        foreach ( (array)
array_keys( $this->query_vars ) as $wpvar ) {
            if (
'' != $this->query_vars[ $wpvar ] ) {
               
$this->query_string .= ( strlen( $this->query_string ) < 1 ) ? '' : '&';
                if ( !
is_scalar( $this->query_vars[ $wpvar ] ) ) { // Discard non-scalars.
                   
continue;
                }
               
$this->query_string .= $wpvar . '=' . rawurlencode( $this->query_vars[ $wpvar ] );
            }
        }

        if (
has_filter( 'query_string' ) ) {  // Don't bother filtering and parsing if no plugins are hooked in.
            /**
             * Filters the query string before parsing.
             *
             * @since 1.5.0
             * @deprecated 2.1.0 Use {@see 'query_vars'} or {@see 'request'} filters instead.
             *
             * @param string $query_string The query string to modify.
             */
           
$this->query_string = apply_filters_deprecated(
               
'query_string',
                array(
$this->query_string ),
               
'2.1.0',
               
'query_vars, request'
           
);
           
parse_str( $this->query_string, $this->query_vars );
        }
    }

   
/**
     * Set up the WordPress Globals.
     *
     * The query_vars property will be extracted to the GLOBALS. So care should
     * be taken when naming global variables that might interfere with the
     * WordPress environment.
     *
     * @since 2.0.0
     *
     * @global WP_Query     $wp_query     WordPress Query object.
     * @global string       $query_string Query string for the loop.
     * @global array        $posts        The found posts.
     * @global WP_Post|null $post         The current post, if available.
     * @global string       $request      The SQL statement for the request.
     * @global int          $more         Only set, if single page or post.
     * @global int          $single       If single page or post. Only set, if single page or post.
     * @global WP_User      $authordata   Only set, if author archive.
     */
   
public function register_globals() {
        global
$wp_query;

       
// Extract updated query vars back into global namespace.
       
foreach ( (array) $wp_query->query_vars as $key => $value ) {
           
$GLOBALS[ $key ] = $value;
        }

       
$GLOBALS['query_string'] = $this->query_string;
       
$GLOBALS['posts']        = & $wp_query->posts;
       
$GLOBALS['post']         = isset( $wp_query->post ) ? $wp_query->post : null;
       
$GLOBALS['request']      = $wp_query->request;

        if (
$wp_query->is_single() || $wp_query->is_page() ) {
           
$GLOBALS['more']   = 1;
           
$GLOBALS['single'] = 1;
        }

        if (
$wp_query->is_author() ) {
           
$GLOBALS['authordata'] = get_userdata( get_queried_object_id() );
        }
    }

   
/**
     * Set up the current user.
     *
     * @since 2.0.0
     */
   
public function init() {
       
wp_get_current_user();
    }

   
/**
     * Set up the Loop based on the query variables.
     *
     * @since 2.0.0
     *
     * @global WP_Query $wp_the_query WordPress Query object.
     */
   
public function query_posts() {
        global
$wp_the_query;
       
$this->build_query_string();
       
$wp_the_query->query( $this->query_vars );
    }

   
/**
     * Set the Headers for 404, if nothing is found for requested URL.
     *
     * Issue a 404 if a request doesn't match any posts and doesn't match any object
     * (e.g. an existing-but-empty category, tag, author) and a 404 was not already issued,
     * and if the request was not a search or the homepage.
     *
     * Otherwise, issue a 200.
     *
     * This sets headers after posts have been queried. handle_404() really means "handle status".
     * By inspecting the result of querying posts, seemingly successful requests can be switched to
     * a 404 so that canonical redirection logic can kick in.
     *
     * @since 2.0.0
     *
     * @global WP_Query $wp_query WordPress Query object.
     */
   
public function handle_404() {
        global
$wp_query;

       
/**
         * Filters whether to short-circuit default header status handling.
         *
         * Returning a non-false value from the filter will short-circuit the handling
         * and return early.
         *
         * @since 4.5.0
         *
         * @param bool     $preempt  Whether to short-circuit default header status handling. Default false.
         * @param WP_Query $wp_query WordPress Query object.
         */
       
if ( false !== apply_filters( 'pre_handle_404', false, $wp_query ) ) {
            return;
        }

       
// If we've already issued a 404, bail.
       
if ( is_404() ) {
            return;
        }

       
$set_404 = true;

       
// Never 404 for the admin, robots, or favicon.
       
if ( is_admin() || is_robots() || is_favicon() ) {
           
$set_404 = false;

           
// If posts were found, check for paged content.
       
} elseif ( $wp_query->posts ) {
           
$content_found = true;

            if (
is_singular() ) {
               
$post = isset( $wp_query->post ) ? $wp_query->post : null;

               
// Only set X-Pingback for single posts that allow pings.
               
if ( $post && pings_open( $post ) && ! headers_sent() ) {
                   
header( 'X-Pingback: ' . get_bloginfo( 'pingback_url', 'display' ) );
                }

               
// Check for paged content that exceeds the max number of pages.
               
$next = '<!--nextpage-->';
                if (
$post && ! empty( $this->query_vars['page'] ) ) {
                   
// Check if content is actually intended to be paged.
                   
if ( false !== strpos( $post->post_content, $next ) ) {
                       
$page          = trim( $this->query_vars['page'], '/' );
                       
$content_found = (int) $page <= ( substr_count( $post->post_content, $next ) + 1 );
                    } else {
                       
$content_found = false;
                    }
                }
            }

           
// The posts page does not support the <!--nextpage--> pagination.
           
if ( $wp_query->is_posts_page && ! empty( $this->query_vars['page'] ) ) {
               
$content_found = false;
            }

            if (
$content_found ) {
               
$set_404 = false;
            }

           
// We will 404 for paged queries, as no posts were found.
       
} elseif ( ! is_paged() ) {
           
$author = get_query_var( 'author' );

           
// Don't 404 for authors without posts as long as they matched an author on this site.
           
if ( is_author() && is_numeric( $author ) && $author > 0 && is_user_member_of_blog( $author )
               
// Don't 404 for these queries if they matched an object.
               
|| ( is_tag() || is_category() || is_tax() || is_post_type_archive() ) && get_queried_object()
               
// Don't 404 for these queries either.
               
|| is_home() || is_search() || is_feed()
            ) {
               
$set_404 = false;
            }
        }

        if (
$set_404 ) {
           
// Guess it's time to 404.
           
$wp_query->set_404();
           
status_header( 404 );
           
nocache_headers();
        } else {
           
status_header( 200 );
        }
    }

   
/**
     * Sets up all of the variables required by the WordPress environment.
     *
     * The action {@see 'wp'} has one parameter that references the WP object. It
     * allows for accessing the properties and methods to further manipulate the
     * object.
     *
     * @since 2.0.0
     *
     * @param string|array $query_args Passed to parse_request().
     */
   
public function main( $query_args = '' ) {
       
$this->init();

       
$parsed = $this->parse_request( $query_args );

       
$this->send_headers();

        if (
$parsed ) {
           
$this->query_posts();
           
$this->handle_404();
           
$this->register_globals();
        }

       
/**
         * Fires once the WordPress environment has been set up.
         *
         * @since 2.1.0
         *
         * @param WP $wp Current WordPress environment instance (passed by reference).
         */
       
do_action_ref_array( 'wp', array( &$this ) );
    }
}