<?php
/**
 * Main WordPress API
 *
 * @package WordPress
 */

require( ABSPATH . WPINC . '/option.php' );

/**
 * Convert given date string into a different format.
 *
 * $format should be either a PHP date format string, e.g. 'U' for a Unix
 * timestamp, or 'G' for a Unix timestamp assuming that $date is GMT.
 *
 * If $translate is true then the given date and format string will
 * be passed to date_i18n() for translation.
 *
 * @since 0.71
 *
 * @param string $format    Format of the date to return.
 * @param string $date      Date string to convert.
 * @param bool   $translate Whether the return date should be translated. Default true.
 * @return string|int|bool Formatted date string or Unix timestamp. False if $date is empty.
 */
function mysql2date( $format, $date, $translate = true ) {
    if ( empty( $date ) )
        return false;

    if ( 'G' == $format )
        return strtotime( $date . ' +0000' );

    $i = strtotime( $date );

    if ( 'U' == $format )
        return $i;

    if ( $translate )
        return date_i18n( $format, $i );
    else
        return date( $format, $i );
}

/**
 * Retrieve the current time based on specified type.
 *
 * The 'mysql' type will return the time in the format for MySQL DATETIME field.
 * The 'timestamp' type will return the current timestamp.
 * Other strings will be interpreted as PHP date formats (e.g. 'Y-m-d').
 *
 * If $gmt is set to either '1' or 'true', then both types will use GMT time.
 * if $gmt is false, the output is adjusted with the GMT offset in the WordPress option.
 *
 * @since 1.0.0
 *
 * @param string   $type Type of time to retrieve. Accepts 'mysql', 'timestamp', or PHP date
 *                       format string (e.g. 'Y-m-d').
 * @param int|bool $gmt  Optional. Whether to use GMT timezone. Default false.
 * @return int|string Integer if $type is 'timestamp', string otherwise.
 */
function current_time( $type, $gmt = 0 ) {
    switch ( $type ) {
        case 'mysql':
            return ( $gmt ) ? gmdate( 'Y-m-d H:i:s' ) : gmdate( 'Y-m-d H:i:s', ( time() + ( get_option( 'gmt_offset' ) * HOUR_IN_SECONDS ) ) );
        case 'timestamp':
            return ( $gmt ) ? time() : time() + ( get_option( 'gmt_offset' ) * HOUR_IN_SECONDS );
        default:
            return ( $gmt ) ? date( $type ) : date( $type, time() + ( get_option( 'gmt_offset' ) * HOUR_IN_SECONDS ) );
    }
}

/**
 * Retrieve the date in localized format, based on timestamp.
 *
 * If the locale specifies the locale month and weekday, then the locale will
 * take over the format for the date. If it isn't, then the date format string
 * will be used instead.
 *
 * @since 0.71
 *
 * @global WP_Locale $wp_locale
 *
 * @param string   $dateformatstring Format to display the date.
 * @param bool|int $unixtimestamp    Optional. Unix timestamp. Default false.
 * @param bool     $gmt              Optional. Whether to use GMT timezone. Default false.
 *
 * @return string The date, translated if locale specifies it.
 */
function date_i18n( $dateformatstring, $unixtimestamp = false, $gmt = false ) {
    global $wp_locale;
    $i = $unixtimestamp;

    if ( false === $i ) {
        if ( ! $gmt )
            $i = current_time( 'timestamp' );
        else
            $i = time();
        // we should not let date() interfere with our
        // specially computed timestamp
        $gmt = true;
    }

    /*
     * Store original value for language with untypical grammars.
     * See https://core.trac.wordpress.org/ticket/9396
     */
    $req_format = $dateformatstring;

    $datefunc = $gmt? 'gmdate' : 'date';

    if ( ( !empty( $wp_locale->month ) ) && ( !empty( $wp_locale->weekday ) ) ) {
        $datemonth = $wp_locale->get_month( $datefunc( 'm', $i ) );
        $datemonth_abbrev = $wp_locale->get_month_abbrev( $datemonth );
        $dateweekday = $wp_locale->get_weekday( $datefunc( 'w', $i ) );
        $dateweekday_abbrev = $wp_locale->get_weekday_abbrev( $dateweekday );
        $datemeridiem = $wp_locale->get_meridiem( $datefunc( 'a', $i ) );
        $datemeridiem_capital = $wp_locale->get_meridiem( $datefunc( 'A', $i ) );
        $dateformatstring = ' '.$dateformatstring;
        $dateformatstring = preg_replace( "/([^\\\])D/", "\\1" . backslashit( $dateweekday_abbrev ), $dateformatstring );
        $dateformatstring = preg_replace( "/([^\\\])F/", "\\1" . backslashit( $datemonth ), $dateformatstring );
        $dateformatstring = preg_replace( "/([^\\\])l/", "\\1" . backslashit( $dateweekday ), $dateformatstring );
        $dateformatstring = preg_replace( "/([^\\\])M/", "\\1" . backslashit( $datemonth_abbrev ), $dateformatstring );
        $dateformatstring = preg_replace( "/([^\\\])a/", "\\1" . backslashit( $datemeridiem ), $dateformatstring );
        $dateformatstring = preg_replace( "/([^\\\])A/", "\\1" . backslashit( $datemeridiem_capital ), $dateformatstring );

        $dateformatstring = substr( $dateformatstring, 1, strlen( $dateformatstring ) -1 );
    }
    $timezone_formats = array( 'P', 'I', 'O', 'T', 'Z', 'e' );
    $timezone_formats_re = implode( '|', $timezone_formats );
    if ( preg_match( "/$timezone_formats_re/", $dateformatstring ) ) {
        $timezone_string = get_option( 'timezone_string' );
        if ( $timezone_string ) {
            $timezone_object = timezone_open( $timezone_string );
            $date_object = date_create( null, $timezone_object );
            foreach ( $timezone_formats as $timezone_format ) {
                if ( false !== strpos( $dateformatstring, $timezone_format ) ) {
                    $formatted = date_format( $date_object, $timezone_format );
                    $dateformatstring = ' '.$dateformatstring;
                    $dateformatstring = preg_replace( "/([^\\\])$timezone_format/", "\\1" . backslashit( $formatted ), $dateformatstring );
                    $dateformatstring = substr( $dateformatstring, 1, strlen( $dateformatstring ) -1 );
                }
            }
        }
    }
    $j = @$datefunc( $dateformatstring, $i );

    /**
     * Filters the date formatted based on the locale.
     *
     * @since 2.8.0
     *
     * @param string $j          Formatted date string.
     * @param string $req_format Format to display the date.
     * @param int    $i          Unix timestamp.
     * @param bool   $gmt        Whether to convert to GMT for time. Default false.
     */
    $j = apply_filters( 'date_i18n', $j, $req_format, $i, $gmt );
    return $j;
}

/**
 * Determines if the date should be declined.
 *
 * If the locale specifies that month names require a genitive case in certain
 * formats (like 'j F Y'), the month name will be replaced with a correct form.
 *
 * @since 4.4.0
 *
 * @param string $date Formatted date string.
 * @return string The date, declined if locale specifies it.
 */
function wp_maybe_decline_date( $date ) {
    global $wp_locale;

    // i18n functions are not available in SHORTINIT mode
    if ( ! function_exists( '_x' ) ) {
        return $date;
    }

    /* translators: If months in your language require a genitive case,
     * translate this to 'on'. Do not translate into your own language.
     */
    if ( 'on' === _x( 'off', 'decline months names: on or off' ) ) {
        // Match a format like 'j F Y' or 'j. F'
        if ( @preg_match( '#^\d{1,2}\.? [^\d ]+#u', $date ) ) {
            $months          = $wp_locale->month;
            $months_genitive = $wp_locale->month_genitive;

            foreach ( $months as $key => $month ) {
                $months[ $key ] = '# ' . $month . '( |$)#u';
            }

            foreach ( $months_genitive as $key => $month ) {
                $months_genitive[ $key ] = ' ' . $month . '$1';
            }

            $date = preg_replace( $months, $months_genitive, $date );
        }
    }

    // Used for locale-specific rules
    $locale = get_locale();

    if ( 'ca' === $locale ) {
        // " de abril| de agost| de octubre..." -> " d'abril| d'agost| d'octubre..."
        $date = preg_replace( '# de ([ao])#i', " d'\\1", $date );
    }

    return $date;
}

/**
 * Convert float number to format based on the locale.
 *
 * @since 2.3.0
 *
 * @global WP_Locale $wp_locale
 *
 * @param float $number   The number to convert based on locale.
 * @param int   $decimals Optional. Precision of the number of decimal places. Default 0.
 * @return string Converted number in string format.
 */
function number_format_i18n( $number, $decimals = 0 ) {
    global $wp_locale;

    if ( isset( $wp_locale ) ) {
        $formatted = number_format( $number, absint( $decimals ), $wp_locale->number_format['decimal_point'], $wp_locale->number_format['thousands_sep'] );
    } else {
        $formatted = number_format( $number, absint( $decimals ) );
    }

    /**
     * Filters the number formatted based on the locale.
     *
     * @since  2.8.0
     *
     * @param string $formatted Converted number in string format.
     */
    return apply_filters( 'number_format_i18n', $formatted );
}

/**
 * Convert number of bytes largest unit bytes will fit into.
 *
 * It is easier to read 1 KB than 1024 bytes and 1 MB than 1048576 bytes. Converts
 * number of bytes to human readable number by taking the number of that unit
 * that the bytes will go into it. Supports TB value.
 *
 * Please note that integers in PHP are limited to 32 bits, unless they are on
 * 64 bit architecture, then they have 64 bit size. If you need to place the
 * larger size then what PHP integer type will hold, then use a string. It will
 * be converted to a double, which should always have 64 bit length.
 *
 * Technically the correct unit names for powers of 1024 are KiB, MiB etc.
 *
 * @since 2.3.0
 *
 * @param int|string $bytes    Number of bytes. Note max integer size for integers.
 * @param int        $decimals Optional. Precision of number of decimal places. Default 0.
 * @return string|false False on failure. Number string on success.
 */
function size_format( $bytes, $decimals = 0 ) {
    $quant = array(
        'TB' => TB_IN_BYTES,
        'GB' => GB_IN_BYTES,
        'MB' => MB_IN_BYTES,
        'KB' => KB_IN_BYTES,
        'B'  => 1,
    );

    if ( 0 === $bytes ) {
        return number_format_i18n( 0, $decimals ) . ' B';
    }

    foreach ( $quant as $unit => $mag ) {
        if ( doubleval( $bytes ) >= $mag ) {
            return number_format_i18n( $bytes / $mag, $decimals ) . ' ' . $unit;
        }
    }

    return false;
}

/**
 * Get the week start and end from the datetime or date string from MySQL.
 *
 * @since 0.71
 *
 * @param string     $mysqlstring   Date or datetime field type from MySQL.
 * @param int|string $start_of_week Optional. Start of the week as an integer. Default empty string.
 * @return array Keys are 'start' and 'end'.
 */
function get_weekstartend( $mysqlstring, $start_of_week = '' ) {
    // MySQL string year.
    $my = substr( $mysqlstring, 0, 4 );

    // MySQL string month.
    $mm = substr( $mysqlstring, 8, 2 );

    // MySQL string day.
    $md = substr( $mysqlstring, 5, 2 );

    // The timestamp for MySQL string day.
    $day = mktime( 0, 0, 0, $md, $mm, $my );

    // The day of the week from the timestamp.
    $weekday = date( 'w', $day );

    if ( !is_numeric($start_of_week) )
        $start_of_week = get_option( 'start_of_week' );

    if ( $weekday < $start_of_week )
        $weekday += 7;

    // The most recent week start day on or before $day.
    $start = $day - DAY_IN_SECONDS * ( $weekday - $start_of_week );

    // $start + 1 week - 1 second.
    $end = $start + WEEK_IN_SECONDS - 1;
    return compact( 'start', 'end' );
}

/**
 * Unserialize value only if it was serialized.
 *
 * @since 2.0.0
 *
 * @param string $original Maybe unserialized original, if is needed.
 * @return mixed Unserialized data can be any type.
 */
function maybe_unserialize( $original ) {
    if ( is_serialized( $original ) ) // don't attempt to unserialize data that wasn't serialized going in
        return @unserialize( $original );
    return $original;
}

/**
 * Check value to find if it was serialized.
 *
 * If $data is not an string, then returned value will always be false.
 * Serialized data is always a string.
 *
 * @since 2.0.5
 *
 * @param string $data   Value to check to see if was serialized.
 * @param bool   $strict Optional. Whether to be strict about the end of the string. Default true.
 * @return bool False if not serialized and true if it was.
 */
function is_serialized( $data, $strict = true ) {
    // if it isn't a string, it isn't serialized.
    if ( ! is_string( $data ) ) {
        return false;
    }
    $data = trim( $data );
    if ( 'N;' == $data ) {
        return true;
    }
    if ( strlen( $data ) < 4 ) {
        return false;
    }
    if ( ':' !== $data[1] ) {
        return false;
    }
    if ( $strict ) {
        $lastc = substr( $data, -1 );
        if ( ';' !== $lastc && '}' !== $lastc ) {
            return false;
        }
    } else {
        $semicolon = strpos( $data, ';' );
        $brace     = strpos( $data, '}' );
        // Either ; or } must exist.
        if ( false === $semicolon && false === $brace )
            return false;
        // But neither must be in the first X characters.
        if ( false !== $semicolon && $semicolon < 3 )
            return false;
        if ( false !== $brace && $brace < 4 )
            return false;
    }
    $token = $data[0];
    switch ( $token ) {
        case 's' :
            if ( $strict ) {
                if ( '"' !== substr( $data, -2, 1 ) ) {
                    return false;
                }
            } elseif ( false === strpos( $data, '"' ) ) {
                return false;
            }
            // or else fall through
        case 'a' :
        case 'O' :
            return (bool) preg_match( "/^{$token}:[0-9]+:/s", $data );
        case 'b' :
        case 'i' :
        case 'd' :
            $end = $strict ? '$' : '';
            return (bool) preg_match( "/^{$token}:[0-9.E-]+;$end/", $data );
    }
    return false;
}

/**
 * Check whether serialized data is of string type.
 *
 * @since 2.0.5
 *
 * @param string $data Serialized data.
 * @return bool False if not a serialized string, true if it is.
 */
function is_serialized_string( $data ) {
    // if it isn't a string, it isn't a serialized string.
    if ( ! is_string( $data ) ) {
        return false;
    }
    $data = trim( $data );
    if ( strlen( $data ) < 4 ) {
        return false;
    } elseif ( ':' !== $data[1] ) {
        return false;
    } elseif ( ';' !== substr( $data, -1 ) ) {
        return false;
    } elseif ( $data[0] !== 's' ) {
        return false;
    } elseif ( '"' !== substr( $data, -2, 1 ) ) {
        return false;
    } else {
        return true;
    }
}

/**
 * Serialize data, if needed.
 *
 * @since 2.0.5
 *
 * @param string|array|object $data Data that might be serialized.
 * @return mixed A scalar data
 */
function maybe_serialize( $data ) {
    if ( is_array( $data ) || is_object( $data ) )
        return serialize( $data );

    // Double serialization is required for backward compatibility.
    // See https://core.trac.wordpress.org/ticket/12930
    // Also the world will end. See WP 3.6.1.
    if ( is_serialized( $data, false ) )
        return serialize( $data );

    return $data;
}

/**
 * Retrieve post title from XMLRPC XML.
 *
 * If the title element is not part of the XML, then the default post title from
 * the $post_default_title will be used instead.
 *
 * @since 0.71
 *
 * @global string $post_default_title Default XML-RPC post title.
 *
 * @param string $content XMLRPC XML Request content
 * @return string Post title
 */
function xmlrpc_getposttitle( $content ) {
    global $post_default_title;
    if ( preg_match( '/<title>(.+?)<\/title>/is', $content, $matchtitle ) ) {
        $post_title = $matchtitle[1];
    } else {
        $post_title = $post_default_title;
    }
    return $post_title;
}

/**
 * Retrieve the post category or categories from XMLRPC XML.
 *
 * If the category element is not found, then the default post category will be
 * used. The return type then would be what $post_default_category. If the
 * category is found, then it will always be an array.
 *
 * @since 0.71
 *
 * @global string $post_default_category Default XML-RPC post category.
 *
 * @param string $content XMLRPC XML Request content
 * @return string|array List of categories or category name.
 */
function xmlrpc_getpostcategory( $content ) {
    global $post_default_category;
    if ( preg_match( '/<category>(.+?)<\/category>/is', $content, $matchcat ) ) {
        $post_category = trim( $matchcat[1], ',' );
        $post_category = explode( ',', $post_category );
    } else {
        $post_category = $post_default_category;
    }
    return $post_category;
}

/**
 * XMLRPC XML content without title and category elements.
 *
 * @since 0.71
 *
 * @param string $content XML-RPC XML Request content.
 * @return string XMLRPC XML Request content without title and category elements.
 */
function xmlrpc_removepostdata( $content ) {
    $content = preg_replace( '/<title>(.+?)<\/title>/si', '', $content );
    $content = preg_replace( '/<category>(.+?)<\/category>/si', '', $content );
    $content = trim( $content );
    return $content;
}

/**
 * Use RegEx to extract URLs from arbitrary content.
 *
 * @since 3.7.0
 *
 * @param string $content Content to extract URLs from.
 * @return array URLs found in passed string.
 */
function wp_extract_urls( $content ) {
    preg_match_all(
        "#([\"']?)("
            . "(?:([\w-]+:)?//?)"
            . "[^\s()<>]+"
            . "[.]"
            . "(?:"
                . "\([\w\d]+\)|"
                . "(?:"
                    . "[^`!()\[\]{};:'\".,<>«»“”‘’\s]|"
                    . "(?:[:]\d+)?/?"
                . ")+"
            . ")"
        . ")\\1#",
        $content,
        $post_links
    );

    $post_links = array_unique( array_map( 'html_entity_decode', $post_links[2] ) );

    return array_values( $post_links );
}

/**
 * Check content for video and audio links to add as enclosures.
 *
 * Will not add enclosures that have already been added and will
 * remove enclosures that are no longer in the post. This is called as
 * pingbacks and trackbacks.
 *
 * @since 1.5.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @param string $content Post Content.
 * @param int    $post_ID Post ID.
 */
function do_enclose( $content, $post_ID ) {
    global $wpdb;

    //TODO: Tidy this ghetto code up and make the debug code optional
    include_once( ABSPATH . WPINC . '/class-IXR.php' );

    $post_links = array();

    $pung = get_enclosed( $post_ID );

    $post_links_temp = wp_extract_urls( $content );

    foreach ( $pung as $link_test ) {
        if ( ! in_array( $link_test, $post_links_temp ) ) { // link no longer in post
            $mids = $wpdb->get_col( $wpdb->prepare("SELECT meta_id FROM $wpdb->postmeta WHERE post_id = %d AND meta_key = 'enclosure' AND meta_value LIKE %s", $post_ID, $wpdb->esc_like( $link_test ) . '%') );
            foreach ( $mids as $mid )
                delete_metadata_by_mid( 'post', $mid );
        }
    }

    foreach ( (array) $post_links_temp as $link_test ) {
        if ( !in_array( $link_test, $pung ) ) { // If we haven't pung it already
            $test = @parse_url( $link_test );
            if ( false === $test )
                continue;
            if ( isset( $test['query'] ) )
                $post_links[] = $link_test;
            elseif ( isset($test['path']) && ( $test['path'] != '/' ) &&  ($test['path'] != '' ) )
                $post_links[] = $link_test;
        }
    }

    /**
     * Filters the list of enclosure links before querying the database.
     *
     * Allows for the addition and/or removal of potential enclosures to save
     * to postmeta before checking the database for existing enclosures.
     *
     * @since 4.4.0
     *
     * @param array $post_links An array of enclosure links.
     * @param int   $post_ID    Post ID.
     */
    $post_links = apply_filters( 'enclosure_links', $post_links, $post_ID );

    foreach ( (array) $post_links as $url ) {
        if ( $url != '' && !$wpdb->get_var( $wpdb->prepare( "SELECT post_id FROM $wpdb->postmeta WHERE post_id = %d AND meta_key = 'enclosure' AND meta_value LIKE %s", $post_ID, $wpdb->esc_like( $url ) . '%' ) ) ) {

            if ( $headers = wp_get_http_headers( $url) ) {
                $len = isset( $headers['content-length'] ) ? (int) $headers['content-length'] : 0;
                $type = isset( $headers['content-type'] ) ? $headers['content-type'] : '';
                $allowed_types = array( 'video', 'audio' );

                // Check to see if we can figure out the mime type from
                // the extension
                $url_parts = @parse_url( $url );
                if ( false !== $url_parts ) {
                    $extension = pathinfo( $url_parts['path'], PATHINFO_EXTENSION );
                    if ( !empty( $extension ) ) {
                        foreach ( wp_get_mime_types() as $exts => $mime ) {
                            if ( preg_match( '!^(' . $exts . ')$!i', $extension ) ) {
                                $type = $mime;
                                break;
                            }
                        }
                    }
                }

                if ( in_array( substr( $type, 0, strpos( $type, "/" ) ), $allowed_types ) ) {
                    add_post_meta( $post_ID, 'enclosure', "$url\n$len\n$mime\n" );
                }
            }
        }
    }
}

/**
 * Retrieve HTTP Headers from URL.
 *
 * @since 1.5.1
 *
 * @param string $url        URL to retrieve HTTP headers from.
 * @param bool   $deprecated Not Used.
 * @return bool|string False on failure, headers on success.
 */
function wp_get_http_headers( $url, $deprecated = false ) {
    if ( !empty( $deprecated ) )
        _deprecated_argument( __FUNCTION__, '2.7.0' );

    $response = wp_safe_remote_head( $url );

    if ( is_wp_error( $response ) )
        return false;

    return wp_remote_retrieve_headers( $response );
}

/**
 * Whether the publish date of the current post in the loop is different from the
 * publish date of the previous post in the loop.
 *
 * @since 0.71
 *
 * @global string $currentday  The day of the current post in the loop.
 * @global string $previousday The day of the previous post in the loop.
 *
 * @return int 1 when new day, 0 if not a new day.
 */
function is_new_day() {
    global $currentday, $previousday;
    if ( $currentday != $previousday )
        return 1;
    else
        return 0;
}

/**
 * Build URL query based on an associative and, or indexed array.
 *
 * This is a convenient function for easily building url queries. It sets the
 * separator to '&' and uses _http_build_query() function.
 *
 * @since 2.3.0
 *
 * @see _http_build_query() Used to build the query
 * @link https://secure.php.net/manual/en/function.http-build-query.php for more on what
 *       http_build_query() does.
 *
 * @param array $data URL-encode key/value pairs.
 * @return string URL-encoded string.
 */
function build_query( $data ) {
    return _http_build_query( $data, null, '&', '', false );
}

/**
 * From php.net (modified by Mark Jaquith to behave like the native PHP5 function).
 *
 * @since 3.2.0
 * @access private
 *
 * @see https://secure.php.net/manual/en/function.http-build-query.php
 *
 * @param array|object  $data       An array or object of data. Converted to array.
 * @param string        $prefix     Optional. Numeric index. If set, start parameter numbering with it.
 *                                  Default null.
 * @param string        $sep        Optional. Argument separator; defaults to 'arg_separator.output'.
 *                                  Default null.
 * @param string        $key        Optional. Used to prefix key name. Default empty.
 * @param bool          $urlencode  Optional. Whether to use urlencode() in the result. Default true.
 *
 * @return string The query string.
 */
function _http_build_query( $data, $prefix = null, $sep = null, $key = '', $urlencode = true ) {
    $ret = array();

    foreach ( (array) $data as $k => $v ) {
        if ( $urlencode)
            $k = urlencode($k);
        if ( is_int($k) && $prefix != null )
            $k = $prefix.$k;
        if ( !empty($key) )
            $k = $key . '%5B' . $k . '%5D';
        if ( $v === null )
            continue;
        elseif ( $v === false )
            $v = '0';

        if ( is_array($v) || is_object($v) )
            array_push($ret,_http_build_query($v, '', $sep, $k, $urlencode));
        elseif ( $urlencode )
            array_push($ret, $k.'='.urlencode($v));
        else
            array_push($ret, $k.'='.$v);
    }

    if ( null === $sep )
        $sep = ini_get('arg_separator.output');

    return implode($sep, $ret);
}

/**
 * Retrieves a modified URL query string.
 *
 * You can rebuild the URL and append query variables to the URL query by using this function.
 * There are two ways to use this function; either a single key and value, or an associative array.
 *
 * Using a single key and value:
 *
 *     add_query_arg( 'key', 'value', 'http://example.com' );
 *
 * Using an associative array:
 *
 *     add_query_arg( array(
 *         'key1' => 'value1',
 *         'key2' => 'value2',
 *     ), 'http://example.com' );
 *
 * Omitting the URL from either use results in the current URL being used
 * (the value of `$_SERVER['REQUEST_URI']`).
 *
 * Values are expected to be encoded appropriately with urlencode() or rawurlencode().
 *
 * Setting any query variable's value to boolean false removes the key (see remove_query_arg()).
 *
 * Important: The return value of add_query_arg() is not escaped by default. Output should be
 * late-escaped with esc_url() or similar to help prevent vulnerability to cross-site scripting
 * (XSS) attacks.
 *
 * @since 1.5.0
 *
 * @param string|array $key   Either a query variable key, or an associative array of query variables.
 * @param string       $value Optional. Either a query variable value, or a URL to act upon.
 * @param string       $url   Optional. A URL to act upon.
 * @return string New URL query string (unescaped).
 */
function add_query_arg() {
    $args = func_get_args();
    if ( is_array( $args[0] ) ) {
        if ( count( $args ) < 2 || false === $args[1] )
            $uri = $_SERVER['REQUEST_URI'];
        else
            $uri = $args[1];
    } else {
        if ( count( $args ) < 3 || false === $args[2] )
            $uri = $_SERVER['REQUEST_URI'];
        else
            $uri = $args[2];
    }

    if ( $frag = strstr( $uri, '#' ) )
        $uri = substr( $uri, 0, -strlen( $frag ) );
    else
        $frag = '';

    if ( 0 === stripos( $uri, 'http://' ) ) {
        $protocol = 'http://';
        $uri = substr( $uri, 7 );
    } elseif ( 0 === stripos( $uri, 'https://' ) ) {
        $protocol = 'https://';
        $uri = substr( $uri, 8 );
    } else {
        $protocol = '';
    }

    if ( strpos( $uri, '?' ) !== false ) {
        list( $base, $query ) = explode( '?', $uri, 2 );
        $base .= '?';
    } elseif ( $protocol || strpos( $uri, '=' ) === false ) {
        $base = $uri . '?';
        $query = '';
    } else {
        $base = '';
        $query = $uri;
    }

    wp_parse_str( $query, $qs );
    $qs = urlencode_deep( $qs ); // this re-URL-encodes things that were already in the query string
    if ( is_array( $args[0] ) ) {
        foreach ( $args[0] as $k => $v ) {
            $qs[ $k ] = $v;
        }
    } else {
        $qs[ $args[0] ] = $args[1];
    }

    foreach ( $qs as $k => $v ) {
        if ( $v === false )
            unset( $qs[$k] );
    }

    $ret = build_query( $qs );
    $ret = trim( $ret, '?' );
    $ret = preg_replace( '#=(&|$)#', '$1', $ret );
    $ret = $protocol . $base . $ret . $frag;
    $ret = rtrim( $ret, '?' );
    return $ret;
}

/**
 * Removes an item or items from a query string.
 *
 * @since 1.5.0
 *
 * @param string|array $key   Query key or keys to remove.
 * @param bool|string  $query Optional. When false uses the current URL. Default false.
 * @return string New URL query string.
 */
function remove_query_arg( $key, $query = false ) {
    if ( is_array( $key ) ) { // removing multiple keys
        foreach ( $key as $k )
            $query = add_query_arg( $k, false, $query );
        return $query;
    }
    return add_query_arg( $key, false, $query );
}

/**
 * Returns an array of single-use query variable names that can be removed from a URL.
 *
 * @since 4.4.0
 *
 * @return array An array of parameters to remove from the URL.
 */
function wp_removable_query_args() {
    $removable_query_args = array(
        'activate',
        'activated',
        'approved',
        'deactivate',
        'deleted',
        'disabled',
        'enabled',
        'error',
        'hotkeys_highlight_first',
        'hotkeys_highlight_last',
        'locked',
        'message',
        'same',
        'saved',
        'settings-updated',
        'skipped',
        'spammed',
        'trashed',
        'unspammed',
        'untrashed',
        'update',
        'updated',
        'wp-post-new-reload',
    );

    /**
     * Filters the list of query variables to remove.
     *
     * @since 4.2.0
     *
     * @param array $removable_query_args An array of query variables to remove from a URL.
     */
    return apply_filters( 'removable_query_args', $removable_query_args );
}

/**
 * Walks the array while sanitizing the contents.
 *
 * @since 0.71
 *
 * @param array $array Array to walk while sanitizing contents.
 * @return array Sanitized $array.
 */
function add_magic_quotes( $array ) {
    foreach ( (array) $array as $k => $v ) {
        if ( is_array( $v ) ) {
            $array[$k] = add_magic_quotes( $v );
        } else {
            $array[$k] = addslashes( $v );
        }
    }
    return $array;
}

/**
 * HTTP request for URI to retrieve content.
 *
 * @since 1.5.1
 *
 * @see wp_safe_remote_get()
 *
 * @param string $uri URI/URL of web page to retrieve.
 * @return false|string HTTP content. False on failure.
 */
function wp_remote_fopen( $uri ) {
    $parsed_url = @parse_url( $uri );

    if ( !$parsed_url || !is_array( $parsed_url ) )
        return false;

    $options = array();
    $options['timeout'] = 10;

    $response = wp_safe_remote_get( $uri, $options );

    if ( is_wp_error( $response ) )
        return false;

    return wp_remote_retrieve_body( $response );
}

/**
 * Set up the WordPress query.
 *
 * @since 2.0.0
 *
 * @global WP       $wp_locale
 * @global WP_Query $wp_query
 * @global WP_Query $wp_the_query
 *
 * @param string|array $query_vars Default WP_Query arguments.
 */
function wp( $query_vars = '' ) {
    global $wp, $wp_query, $wp_the_query;
    $wp->main( $query_vars );

    if ( !isset($wp_the_query) )
        $wp_the_query = $wp_query;
}

/**
 * Retrieve the description for the HTTP status.
 *
 * @since 2.3.0
 *
 * @global array $wp_header_to_desc
 *
 * @param int $code HTTP status code.
 * @return string Empty string if not found, or description if found.
 */
function get_status_header_desc( $code ) {
    global $wp_header_to_desc;

    $code = absint( $code );

    if ( !isset( $wp_header_to_desc ) ) {
        $wp_header_to_desc = array(
            100 => 'Continue',
            101 => 'Switching Protocols',
            102 => 'Processing',

            200 => 'OK',
            201 => 'Created',
            202 => 'Accepted',
            203 => 'Non-Authoritative Information',
            204 => 'No Content',
            205 => 'Reset Content',
            206 => 'Partial Content',
            207 => 'Multi-Status',
            226 => 'IM Used',

            300 => 'Multiple Choices',
            301 => 'Moved Permanently',
            302 => 'Found',
            303 => 'See Other',
            304 => 'Not Modified',
            305 => 'Use Proxy',
            306 => 'Reserved',
            307 => 'Temporary Redirect',
            308 => 'Permanent Redirect',

            400 => 'Bad Request',
            401 => 'Unauthorized',
            402 => 'Payment Required',
            403 => 'Forbidden',
            404 => 'Not Found',
            405 => 'Method Not Allowed',
            406 => 'Not Acceptable',
            407 => 'Proxy Authentication Required',
            408 => 'Request Timeout',
            409 => 'Conflict',
            410 => 'Gone',
            411 => 'Length Required',
            412 => 'Precondition Failed',
            413 => 'Request Entity Too Large',
            414 => 'Request-URI Too Long',
            415 => 'Unsupported Media Type',
            416 => 'Requested Range Not Satisfiable',
            417 => 'Expectation Failed',
            418 => 'I\'m a teapot',
            421 => 'Misdirected Request',
            422 => 'Unprocessable Entity',
            423 => 'Locked',
            424 => 'Failed Dependency',
            426 => 'Upgrade Required',
            428 => 'Precondition Required',
            429 => 'Too Many Requests',
            431 => 'Request Header Fields Too Large',
            451 => 'Unavailable For Legal Reasons',

            500 => 'Internal Server Error',
            501 => 'Not Implemented',
            502 => 'Bad Gateway',
            503 => 'Service Unavailable',
            504 => 'Gateway Timeout',
            505 => 'HTTP Version Not Supported',
            506 => 'Variant Also Negotiates',
            507 => 'Insufficient Storage',
            510 => 'Not Extended',
            511 => 'Network Authentication Required',
        );
    }

    if ( isset( $wp_header_to_desc[$code] ) )
        return $wp_header_to_desc[$code];
    else
        return '';
}

/**
 * Set HTTP status header.
 *
 * @since 2.0.0
 * @since 4.4.0 Added the `$description` parameter.
 *
 * @see get_status_header_desc()
 *
 * @param int    $code        HTTP status code.
 * @param string $description Optional. A custom description for the HTTP status.
 */
function status_header( $code, $description = '' ) {
    if ( ! $description ) {
        $description = get_status_header_desc( $code );
    }

    if ( empty( $description ) ) {
        return;
    }

    $protocol = wp_get_server_protocol();
    $status_header = "$protocol $code $description";
    if ( function_exists( 'apply_filters' ) )

        /**
         * Filters an HTTP status header.
         *
         * @since 2.2.0
         *
         * @param string $status_header HTTP status header.
         * @param int    $code          HTTP status code.
         * @param string $description   Description for the status code.
         * @param string $protocol      Server protocol.
         */
        $status_header = apply_filters( 'status_header', $status_header, $code, $description, $protocol );

    @header( $status_header, true, $code );
}

/**
 * Get the header information to prevent caching.
 *
 * The several different headers cover the different ways cache prevention
 * is handled by different browsers
 *
 * @since 2.8.0
 *
 * @return array The associative array of header names and field values.
 */
function wp_get_nocache_headers() {
    $headers = array(
        'Expires' => 'Wed, 11 Jan 1984 05:00:00 GMT',
        'Cache-Control' => 'no-cache, must-revalidate, max-age=0',
    );

    if ( function_exists('apply_filters') ) {
        /**
         * Filters the cache-controlling headers.
         *
         * @since 2.8.0
         *
         * @see wp_get_nocache_headers()
         *
         * @param array $headers {
         *     Header names and field values.
         *
         *     @type string $Expires       Expires header.
         *     @type string $Cache-Control Cache-Control header.
         * }
         */
        $headers = (array) apply_filters( 'nocache_headers', $headers );
    }
    $headers['Last-Modified'] = false;
    return $headers;
}

/**
 * Set the headers to prevent caching for the different browsers.
 *
 * Different browsers support different nocache headers, so several
 * headers must be sent so that all of them get the point that no
 * caching should occur.
 *
 * @since 2.0.0
 *
 * @see wp_get_nocache_headers()
 */
function nocache_headers() {
    $headers = wp_get_nocache_headers();

    unset( $headers['Last-Modified'] );

    // In PHP 5.3+, make sure we are not sending a Last-Modified header.
    if ( function_exists( 'header_remove' ) ) {
        @header_remove( 'Last-Modified' );
    } else {
        // In PHP 5.2, send an empty Last-Modified header, but only as a
        // last resort to override a header already sent. #WP23021
        foreach ( headers_list() as $header ) {
            if ( 0 === stripos( $header, 'Last-Modified' ) ) {
                $headers['Last-Modified'] = '';
                break;
            }
        }
    }

    foreach ( $headers as $name => $field_value )
        @header("{$name}: {$field_value}");
}

/**
 * Set the headers for caching for 10 days with JavaScript content type.
 *
 * @since 2.1.0
 */
function cache_javascript_headers() {
    $expiresOffset = 10 * DAY_IN_SECONDS;

    header( "Content-Type: text/javascript; charset=" . get_bloginfo( 'charset' ) );
    header( "Vary: Accept-Encoding" ); // Handle proxies
    header( "Expires: " . gmdate( "D, d M Y H:i:s", time() + $expiresOffset ) . " GMT" );
}

/**
 * Retrieve the number of database queries during the WordPress execution.
 *
 * @since 2.0.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @return int Number of database queries.
 */
function get_num_queries() {
    global $wpdb;
    return $wpdb->num_queries;
}

/**
 * Whether input is yes or no.
 *
 * Must be 'y' to be true.
 *
 * @since 1.0.0
 *
 * @param string $yn Character string containing either 'y' (yes) or 'n' (no).
 * @return bool True if yes, false on anything else.
 */
function bool_from_yn( $yn ) {
    return ( strtolower( $yn ) == 'y' );
}

/**
 * Load the feed template from the use of an action hook.
 *
 * If the feed action does not have a hook, then the function will die with a
 * message telling the visitor that the feed is not valid.
 *
 * It is better to only have one hook for each feed.
 *
 * @since 2.1.0
 *
 * @global WP_Query $wp_query Used to tell if the use a comment feed.
 */
function do_feed() {
    global $wp_query;

    $feed = get_query_var( 'feed' );

    // Remove the pad, if present.
    $feed = preg_replace( '/^_+/', '', $feed );

    if ( $feed == '' || $feed == 'feed' )
        $feed = get_default_feed();

    if ( ! has_action( "do_feed_{$feed}" ) ) {
        wp_die( __( 'ERROR: This is not a valid feed template.' ), '', array( 'response' => 404 ) );
    }

    /**
     * Fires once the given feed is loaded.
     *
     * The dynamic portion of the hook name, `$feed`, refers to the feed template name.
     * Possible values include: 'rdf', 'rss', 'rss2', and 'atom'.
     *
     * @since 2.1.0
     * @since 4.4.0 The `$feed` parameter was added.
     *
     * @param bool   $is_comment_feed Whether the feed is a comment feed.
     * @param string $feed            The feed name.
     */
    do_action( "do_feed_{$feed}", $wp_query->is_comment_feed, $feed );
}

/**
 * Load the RDF RSS 0.91 Feed template.
 *
 * @since 2.1.0
 *
 * @see load_template()
 */
function do_feed_rdf() {
    load_template( ABSPATH . WPINC . '/feed-rdf.php' );
}

/**
 * Load the RSS 1.0 Feed Template.
 *
 * @since 2.1.0
 *
 * @see load_template()
 */
function do_feed_rss() {
    load_template( ABSPATH . WPINC . '/feed-rss.php' );
}

/**
 * Load either the RSS2 comment feed or the RSS2 posts feed.
 *
 * @since 2.1.0
 *
 * @see load_template()
 *
 * @param bool $for_comments True for the comment feed, false for normal feed.
 */
function do_feed_rss2( $for_comments ) {
    if ( $for_comments )
        load_template( ABSPATH . WPINC . '/feed-rss2-comments.php' );
    else
        load_template( ABSPATH . WPINC . '/feed-rss2.php' );
}

/**
 * Load either Atom comment feed or Atom posts feed.
 *
 * @since 2.1.0
 *
 * @see load_template()
 *
 * @param bool $for_comments True for the comment feed, false for normal feed.
 */
function do_feed_atom( $for_comments ) {
    if ($for_comments)
        load_template( ABSPATH . WPINC . '/feed-atom-comments.php');
    else
        load_template( ABSPATH . WPINC . '/feed-atom.php' );
}

/**
 * Display the robots.txt file content.
 *
 * The echo content should be with usage of the permalinks or for creating the
 * robots.txt file.
 *
 * @since 2.1.0
 */
function do_robots() {
    header( 'Content-Type: text/plain; charset=utf-8' );

    /**
     * Fires when displaying the robots.txt file.
     *
     * @since 2.1.0
     */
    do_action( 'do_robotstxt' );

    $output = "User-agent: *\n";
    $public = get_option( 'blog_public' );
    if ( '0' == $public ) {
        $output .= "Disallow: /\n";
    } else {
        $site_url = parse_url( site_url() );
        $path = ( !empty( $site_url['path'] ) ) ? $site_url['path'] : '';
        $output .= "Disallow: $path/wp-admin/\n";
        $output .= "Allow: $path/wp-admin/admin-ajax.php\n";
    }

    /**
     * Filters the robots.txt output.
     *
     * @since 3.0.0
     *
     * @param string $output Robots.txt output.
     * @param bool   $public Whether the site is considered "public".
     */
    echo apply_filters( 'robots_txt', $output, $public );
}

/**
 * Test whether WordPress is already installed.
 *
 * The cache will be checked first. If you have a cache plugin, which saves
 * the cache values, then this will work. If you use the default WordPress
 * cache, and the database goes away, then you might have problems.
 *
 * Checks for the 'siteurl' option for whether WordPress is installed.
 *
 * @since 2.1.0
 *
 * @global wpdb $wpdb WordPress database abstraction object.
 *
 * @return bool Whether the site is already installed.
 */
function is_blog_installed() {
    global $wpdb;

    /*
     * Check cache first. If options table goes away and we have true
     * cached, oh well.
     */
    if ( wp_cache_get( 'is_blog_installed' ) )
        return true;

    $suppress = $wpdb->suppress_errors();
    if ( ! wp_installing() ) {
        $alloptions = wp_load_alloptions();
    }
    // If siteurl is not set to autoload, check it specifically
    if ( !isset( $alloptions['siteurl'] ) )
        $installed = $wpdb->get_var( "SELECT option_value FROM $wpdb->options WHERE option_name = 'siteurl'" );
    else
        $installed = $alloptions['siteurl'];
    $wpdb->suppress_errors( $suppress );

    $installed = !empty( $installed );
    wp_cache_set( 'is_blog_installed', $installed );

    if ( $installed )
        return true;

    // If visiting repair.php, return true and let it take over.
    if ( defined( 'WP_REPAIRING' ) )
        return true;

    $suppress = $wpdb->suppress_errors();

    /*
     * Loop over the WP tables. If none exist, then scratch install is allowed.
     * If one or more exist, suggest table repair since we got here because the
     * options table could not be accessed.
     */
    $wp_tables = $wpdb->tables();
    foreach ( $wp_tables as $table ) {
        // The existence of custom user tables shouldn't suggest an insane state or prevent a clean install.
        if ( defined( 'CUSTOM_USER_TABLE' ) && CUSTOM_USER_TABLE == $table )
            continue;
        if ( defined( 'CUSTOM_USER_META_TABLE' ) && CUSTOM_USER_META_TABLE == $table )
            continue;

        if ( ! $wpdb->get_results( "DESCRIBE $table;" ) )
            continue;

        // One or more tables exist. We are insane.

        wp_load_translations_early();

        // Die with a DB error.
        $wpdb->error = sprintf( __( 'One or more database tables are unavailable. The database may need to be <a href="%s">repaired</a>.' ), 'maint/repair.php?referrer=is_blog_installed' );
        dead_db();
    }

    $wpdb->suppress_errors( $suppress );

    wp_cache_set( 'is_blog_installed', false );

    return false;
}

/**
 * Retrieve URL with nonce added to URL query.
 *
 * @since 2.0.4
 *
 * @param string     $actionurl URL to add nonce action.
 * @param int|string $action    Optional. Nonce action name. Default -1.
 * @param string     $name      Optional. Nonce name. Default '_wpnonce'.
 * @return string Escaped URL with nonce action added.
 */
function wp_nonce_url( $actionurl, $action = -1, $name = '_wpnonce' ) {
    $actionurl = str_replace( '&', '&', $actionurl );
    return esc_html( add_query_arg( $name, wp_create_nonce( $action ), $actionurl ) );
}

/**
 * Retrieve or display nonce hidden field for forms.
 *
 * The nonce field is used to validate that the contents of the form came from
 * the location on the current site and not somewhere else. The nonce does not
 * offer absolute protection, but should protect against most cases. It is very
 * important to use nonce field in forms.
 *
 * The $action and $name are optional, but if you want to have better security,
 * it is strongly suggested to set those two parameters. It is easier to just
 * call the function without any parameters, because validation of the nonce
 * doesn't require any parameters, but since crackers know what the default is
 * it won't be difficult for them to find a way around your nonce and cause
 * damage.
 *
 * The input name will be whatever $name value you gave. The input value will be
 * the nonce creation value.
 *
 * @since 2.0.4
 *
 * @param int|string $action  Optional. Action name. Default -1.
 * @param string     $name    Optional. Nonce name. Default '_wpnonce'.
 * @param bool       $referer Optional. Whether to set the referer field for validation. Default true.
 * @param bool       $echo    Optional. Whether to display or return hidden form field. Default true.
 * @return string Nonce field HTML markup.
 */
function wp_nonce_field( $action = -1, $name = "_wpnonce", $referer = true , $echo = true ) {
    $name = esc_attr( $name );
    $nonce_field = '<input type="hidden" id="' . $name . '" name="' . $name . '" value="' . wp_create_nonce( $action ) . '" />';

    if ( $referer )
        $nonce_field .= wp_referer_field( false );

    if ( $echo )
        echo $nonce_field;

    return $nonce_field;
}

/**
 * Retrieve or display referer hidden field for forms.
 *
 * The referer link is the current Request URI from the server super global. The
 * input name is '_wp_http_referer', in case you wanted to check manually.
 *
 * @since 2.0.4
 *
 * @param bool $echo Optional. Whether to echo or return the referer field. Default true.
 * @return string Referer field HTML markup.
 */
function wp_referer_field( $echo = true ) {
    $referer_field = '<input type="hidden" name="_wp_http_referer" value="'. esc_attr( wp_unslash( $_SERVER['REQUEST_URI'] ) ) . '" />';

    if ( $echo )
        echo $referer_field;
    return $referer_field;
}

/**
 * Retrieve or display original referer hidden field for forms.
 *
 * The input name is '_wp_original_http_referer' and will be either the same
 * value of wp_referer_field(), if that was posted already or it will be the
 * current page, if it doesn't exist.
 *
 * @since 2.0.4
 *
 * @param bool   $echo         Optional. Whether to echo the original http referer. Default true.
 * @param string $jump_back_to Optional. Can be 'previous' or page you want to jump back to.
 *                             Default 'current'.
 * @return string Original referer field.
 */
function wp_original_referer_field( $echo = true, $jump_back_to = 'current' ) {
    if ( ! $ref = wp_get_original_referer() ) {
        $ref = 'previous' == $jump_back_to ? wp_get_referer() : wp_unslash( $_SERVER['REQUEST_URI'] );
    }
    $orig_referer_field = '<input type="hidden" name="_wp_original_http_referer" value="' . esc_attr( $ref ) . '" />';
    if ( $echo )
        echo $orig_referer_field;
    return $orig_referer_field;
}

/**
 * Retrieve referer from '_wp_http_referer' or HTTP referer.
 *
 * If it's the same as the current request URL, will return false.
 *
 * @since 2.0.4
 *
 * @return false|string False on failure. Referer URL on success.
 */
function wp_get_referer() {
    if ( ! function_exists( 'wp_validate_redirect' ) ) {
        return false;
    }

    $ref = wp_get_raw_referer();

    if ( $ref && $ref !== wp_unslash( $_SERVER['REQUEST_URI'] ) && $ref !== home_url() . wp_unslash( $_SERVER['REQUEST_URI'] ) ) {
        return wp_validate_redirect( $ref, false );
    }

    return false;
}

/**
 * Retrieves unvalidated referer from '_wp_http_referer' or HTTP referer.
 *
 * Do not use for redirects, use wp_get_referer() instead.
 *
 * @since 4.5.0
 *
 * @return string|false Referer URL on success, false on failure.
 */
function wp_get_raw_referer() {
    if ( ! empty( $_REQUEST['_wp_http_referer'] ) ) {
        return wp_unslash( $_REQUEST['_wp_http_referer'] );
    } else if ( ! empty( $_SERVER['HTTP_REFERER'] ) ) {
        return wp_unslash( $_SERVER['HTTP_REFERER'] );
    }

    return false;
}

/**
 * Retrieve original referer that was posted, if it exists.
 *
 * @since 2.0.4
 *
 * @return string|false False if no original referer or original referer if set.
 */
function wp_get_original_referer() {
    if ( ! empty( $_REQUEST['_wp_original_http_referer'] ) && function_exists( 'wp_validate_redirect' ) )
        return wp_validate_redirect( wp_unslash( $_REQUEST['_wp_original_http_referer'] ), false );
    return false;
}

/**
 * Recursive directory creation based on full path.
 *
 * Will attempt to set permissions on folders.
 *
 * @since 2.0.1
 *
 * @param string $target Full path to attempt to create.
 * @return bool Whether the path was created. True if path already exists.
 */
function wp_mkdir_p( $target ) {
    $wrapper = null;

    // Strip the protocol.
    if ( wp_is_stream( $target ) ) {
        list( $wrapper, $target ) = explode( '://', $target, 2 );
    }

    // From php.net/mkdir user contributed notes.
    $target = str_replace( '//', '/', $target );

    // Put the wrapper back on the target.
    if ( $wrapper !== null ) {
        $target = $wrapper . '://' . $target;
    }

    /*
     * Safe mode fails with a trailing slash under certain PHP versions.
     * Use rtrim() instead of untrailingslashit to avoid formatting.php dependency.
     */
    $target = rtrim($target, '/');
    if ( empty($target) )
        $target = '/';

    if ( file_exists( $target ) )
        return @is_dir( $target );

    // We need to find the permissions of the parent folder that exists and inherit that.
    $target_parent = dirname( $target );
    while ( '.' != $target_parent && ! is_dir( $target_parent ) ) {
        $target_parent = dirname( $target_parent );
    }

    // Get the permission bits.
    if ( $stat = @stat( $target_parent ) ) {
        $dir_perms = $stat['mode'] & 0007777;
    } else {
        $dir_perms = 0777;
    }

    if ( @mkdir( $target, $dir_perms, true ) ) {

        /*
         * If a umask is set that modifies $dir_perms, we'll have to re-set
         * the $dir_perms correctly with chmod()
         */
        if ( $dir_perms != ( $dir_perms & ~umask() ) ) {
            $folder_parts = explode( '/', substr( $target, strlen( $target_parent ) + 1 ) );
            for ( $i = 1, $c = count( $folder_parts ); $i <= $c; $i++ ) {
                @chmod( $target_parent . '/' . implode( '/', array_slice( $folder_parts, 0, $i ) ), $dir_perms );
            }
        }

        return true;
    }

    return false;
}

/**
 * Test if a give filesystem path is absolute.
 *
 * For example, '/foo/bar', or 'c:\windows'.
 *
 * @since 2.5.0
 *
 * @param string $path File path.
 * @return bool True if path is absolute, false is not absolute.
 */
function path_is_absolute( $path ) {
    /*
     * This is definitive if true but fails if $path does not exist or contains
     * a symbolic link.
     */
    if ( realpath($path) == $path )
        return true;

    if ( strlen($path) == 0 || $path[0] == '.' )
        return false;

    // Windows allows absolute paths like this.
    if ( preg_match('#^[a-zA-Z]:\\\\#', $path) )
        return true;

    // A path starting with / or \ is absolute; anything else is relative.
    return ( $path[0] == '/' || $path[0] == '\\' );
}

/**
 * Join two filesystem paths together.
 *
 * For example, 'give me $path relative to $base'. If the $path is absolute,
 * then it the full path is returned.
 *
 * @since 2.5.0
 *
 * @param string $base Base path.
 * @param string $path Path relative to $base.
 * @return string The path with the base or absolute path.
 */
function path_join( $base, $path ) {
    if ( path_is_absolute($path) )
        return $path;

    return rtrim($base, '/') . '/' . ltrim($path, '/');
}

/**
 * Normalize a filesystem path.
 *
 * On windows systems, replaces backslashes with forward slashes
 * and forces upper-case drive letters.
 * Allows for two leading slashes for Windows network shares, but
 * ensures that all other duplicate slashes are reduced to a single.
 *
 * @since 3.9.0
 * @since 4.4.0 Ensures upper-case drive letters on Windows systems.
 * @since 4.5.0 Allows for Windows network shares.
 *
 * @param string $path Path to normalize.
 * @return string Normalized path.
 */
function wp_normalize_path( $path ) {
    $path = str_replace( '\\', '/', $path );
    $path = preg_replace( '|(?<=.)/+|', '/', $path );
    if ( ':' === substr( $path, 1, 1 ) ) {
        $path = ucfirst( $path );
    }
    return $path;
}

/**
 * Determine a writable directory for temporary files.
 *
 * Function's preference is the return value of sys_get_temp_dir(),
 * followed by your PHP temporary upload directory, followed by WP_CONTENT_DIR,
 * before finally defaulting to /tmp/
 *
 * In the event that this function does not find a writable location,
 * It may be overridden by the WP_TEMP_DIR constant in your wp-config.php file.
 *
 * @since 2.5.0
 *
 * @staticvar string $temp
 *
 * @return string Writable temporary directory.
 */
function get_temp_dir() {
    static $temp = '';
    if ( defined('WP_TEMP_DIR') )
        return trailingslashit(WP_TEMP_DIR);

    if ( $temp )
        return trailingslashit( $temp );

    if ( function_exists('sys_get_temp_dir') ) {
        $temp = sys_get_temp_dir();
        if ( @is_dir( $temp ) && wp_is_writable( $temp ) )
            return trailingslashit( $temp );
    }

    $temp = ini_get('upload_tmp_dir');
    if ( @is_dir( $temp ) && wp_is_writable( $temp ) )
        return trailingslashit( $temp );

    $temp = WP_CONTENT_DIR . '/';
    if ( is_dir( $temp ) && wp_is_writable( $temp ) )
        return $temp;

    return '/tmp/';
}

/**
 * Determine if a directory is writable.
 *
 * This function is used to work around certain ACL issues in PHP primarily
 * affecting Windows Servers.
 *
 * @since 3.6.0
 *
 * @see win_is_writable()
 *
 * @param string $path Path to check for write-ability.
 * @return bool Whether the path is writable.
 */
function wp_is_writable( $path ) {
    if ( 'WIN' === strtoupper( substr( PHP_OS, 0, 3 ) ) )
        return win_is_writable( $path );
    else
        return @is_writable( $path );
}

/**
 * Workaround for Windows bug in is_writable() function
 *
 * PHP has issues with Windows ACL's for determine if a
 * directory is writable or not, this works around them by
 * checking the ability to open files rather than relying
 * upon PHP to interprate the OS ACL.
 *
 * @since 2.8.0
 *
 * @see https://bugs.php.net/bug.php?id=27609
 * @see https://bugs.php.net/bug.php?id=30931
 *
 * @param string $path Windows path to check for write-ability.
 * @return bool Whether the path is writable.
 */
function win_is_writable( $path ) {

    if ( $path[strlen( $path ) - 1] == '/' ) { // if it looks like a directory, check a random file within the directory
        return win_is_writable( $path . uniqid( mt_rand() ) . '.tmp');
    } elseif ( is_dir( $path ) ) { // If it's a directory (and not a file) check a random file within the directory
        return win_is_writable( $path . '/' . uniqid( mt_rand() ) . '.tmp' );
    }
    // check tmp file for read/write capabilities
    $should_delete_tmp_file = !file_exists( $path );
    $f = @fopen( $path, 'a' );
    if ( $f === false )
        return false;
    fclose( $f );
    if ( $should_delete_tmp_file )
        unlink( $path );
    return true;
}

/**
 * Retrieves uploads directory information.
 *
 * Same as wp_upload_dir() but "light weight" as it doesn't attempt to create the uploads directory.
 * Intended for use in themes, when only 'basedir' and 'baseurl' are needed, generally in all cases
 * when not uploading files.
 *
 * @since 4.5.0
 *
 * @see wp_upload_dir()
 *
 * @return array See wp_upload_dir() for description.
 */
function wp_get_upload_dir() {
    return wp_upload_dir( null, false );
}

/**
 * Get an array containing the current upload directory's path and url.
 *
 * Checks the 'upload_path' option, which should be from the web root folder,
 * and if it isn't empty it will be used. If it is empty, then the path will be
 * 'WP_CONTENT_DIR/uploads'. If the 'UPLOADS' constant is defined, then it will
 * override the 'upload_path' option and 'WP_CONTENT_DIR/uploads' path.
 *
 * The upload URL path is set either by the 'upload_url_path' option or by using
 * the 'WP_CONTENT_URL' constant and appending '/uploads' to the path.
 *
 * If the 'uploads_use_yearmonth_folders' is set to true (checkbox if checked in
 * the administration settings panel), then the time will be used. The format
 * will be year first and then month.
 *
 * If the path couldn't be created, then an error will be returned with the key
 * 'error' containing the error message. The error suggests that the parent
 * directory is not writable by the server.
 *
 * On success, the returned array will have many indices:
 * 'path' - base directory and sub directory or full path to upload directory.
 * 'url' - base url and sub directory or absolute URL to upload directory.
 * 'subdir' - sub directory if uploads use year/month folders option is on.
 * 'basedir' - path without subdir.
 * 'baseurl' - URL path without subdir.
 * 'error' - false or error message.
 *
 * @since 2.0.0
 * @uses _wp_upload_dir()
 *
 * @param string $time Optional. Time formatted in 'yyyy/mm'. Default null.
 * @param bool   $create_dir Optional. Whether to check and create the uploads directory.
 *                           Default true for backward compatibility.
 * @param bool   $refresh_cache Optional. Whether to refresh the cache. Default false.
 * @return array See above for description.
 */
function wp_upload_dir( $time = null, $create_dir = true, $refresh_cache = false ) {
    static $cache = array(), $tested_paths = array();

    $key = sprintf( '%d-%s', get_current_blog_id(), (string) $time );

    if ( $refresh_cache || empty( $cache[ $key ] ) ) {
        $cache[ $key ] = _wp_upload_dir( $time );
    }

    /**
     * Filters the uploads directory data.
     *
     * @since 2.0.0