Proyectos de Subversion Moodle

<?php

/**

 * SimplePie

 *

 * A PHP-Based RSS and Atom Feed Framework.

 * Takes the hard work out of managing a complete RSS/Atom solution.

 *

 * Copyright (c) 2004-2022, Ryan Parman, Sam Sneddon, Ryan McCue, and contributors

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without modification, are

 * permitted provided that the following conditions are met:

 *

 * 	* Redistributions of source code must retain the above copyright notice, this list of

 * 	  conditions and the following disclaimer.

 *

 * 	* Redistributions in binary form must reproduce the above copyright notice, this list

 * 	  of conditions and the following disclaimer in the documentation and/or other materials

 * 	  provided with the distribution.

 *

 * 	* Neither the name of the SimplePie Team nor the names of its contributors may be used

 * 	  to endorse or promote products derived from this software without specific prior

 * 	  written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS

 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY

 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS

 * AND CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR

 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR

 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

 * POSSIBILITY OF SUCH DAMAGE.

 *

 * @package SimplePie

 * @copyright 2004-2016 Ryan Parman, Sam Sneddon, Ryan McCue

 * @author Ryan Parman

 * @author Sam Sneddon

 * @author Ryan McCue

 * @link http://simplepie.org/ SimplePie

 * @license http://www.opensource.org/licenses/bsd-license.php BSD License

 */

namespace SimplePie;

/**

 * IRI parser/serialiser/normaliser

 *

 * @package SimplePie

 * @subpackage HTTP

 * @author Sam Sneddon

 * @author Steve Minutillo

 * @author Ryan McCue

 * @copyright 2007-2012 Sam Sneddon, Steve Minutillo, Ryan McCue

 * @license http://www.opensource.org/licenses/bsd-license.php

 */

class IRI

{

    /**

     * Scheme

     *

     * @var string

     */

    protected $scheme = null;

    /**

     * User Information

     *

     * @var string

     */

    protected $iuserinfo = null;

    /**

     * ihost

     *

     * @var string

     */

    protected $ihost = null;

    /**

     * Port

     *

     * @var string

     */

    protected $port = null;

    /**

     * ipath

     *

     * @var string

     */

    protected $ipath = '';

    /**

     * iquery

     *

     * @var string

     */

    protected $iquery = null;

    /**

     * ifragment

     *

     * @var string

     */

    protected $ifragment = null;

    /**

     * Normalization database

     *

     * Each key is the scheme, each value is an array with each key as the IRI

     * part and value as the default value for that part.

     */

    protected $normalization = [

        'acap' => [

            'port' => 674

        ],

        'dict' => [

            'port' => 2628

        ],

        'file' => [

            'ihost' => 'localhost'

        ],

        'http' => [

            'port' => 80,

            'ipath' => '/'

        ],

        'https' => [

            'port' => 443,

            'ipath' => '/'

        ],

    ];

    /**

     * Return the entire IRI when you try and read the object as a string

     *

     * @return string

     */

    public function __toString()

    {

        return $this->get_iri();

    }

    /**

     * Overload __set() to provide access via properties

     *

     * @param string $name Property name

     * @param mixed $value Property value

     */

    public function __set($name, $value)

    {

        if (method_exists($this, 'set_' . $name)) {

            call_user_func([$this, 'set_' . $name], $value);

        } elseif (

            $name === 'iauthority'

            || $name === 'iuserinfo'

            || $name === 'ihost'

            || $name === 'ipath'

            || $name === 'iquery'

            || $name === 'ifragment'

        ) {

            call_user_func([$this, 'set_' . substr($name, 1)], $value);

        }

    }

    /**

     * Overload __get() to provide access via properties

     *

     * @param string $name Property name

     * @return mixed

     */

    public function __get($name)

    {

        // isset() returns false for null, we don't want to do that

        // Also why we use array_key_exists below instead of isset()

        $props = get_object_vars($this);

        if (

            $name === 'iri' ||

            $name === 'uri' ||

            $name === 'iauthority' ||

            $name === 'authority'

        ) {

            $return = $this->{"get_$name"}();

        } elseif (array_key_exists($name, $props)) {

            $return = $this->$name;

        }

        // host -> ihost

        elseif (($prop = 'i' . $name) && array_key_exists($prop, $props)) {

            $name = $prop;

            $return = $this->$prop;

        }

        // ischeme -> scheme

        elseif (($prop = substr($name, 1)) && array_key_exists($prop, $props)) {

            $name = $prop;

            $return = $this->$prop;

        } else {

            trigger_error('Undefined property: ' . get_class($this) . '::' . $name, E_USER_NOTICE);

            $return = null;

        }

        if ($return === null && isset($this->normalization[$this->scheme][$name])) {

            return $this->normalization[$this->scheme][$name];

        }

        return $return;

    }

    /**

     * Overload __isset() to provide access via properties

     *

     * @param string $name Property name

     * @return bool

     */

    public function __isset($name)

    {

        return method_exists($this, 'get_' . $name) || isset($this->$name);

    }

    /**

     * Overload __unset() to provide access via properties

     *

     * @param string $name Property name

     */

    public function __unset($name)

    {

        if (method_exists($this, 'set_' . $name)) {

            call_user_func([$this, 'set_' . $name], '');

        }

    }

    /**

     * Create a new IRI object, from a specified string

     *

     * @param string $iri

     */

    public function __construct($iri = null)

    {

        $this->set_iri($iri);

    }

    /**

     * Clean up

     */

    public function __destruct()

    {

        $this->set_iri(null, true);

        $this->set_path(null, true);

        $this->set_authority(null, true);

    }

    /**

     * Create a new IRI object by resolving a relative IRI

     *

     * Returns false if $base is not absolute, otherwise an IRI.

     *

     * @param IRI|string $base (Absolute) Base IRI

     * @param IRI|string $relative Relative IRI

     * @return IRI|false

     */

    public static function absolutize($base, $relative)

    {

        if (!($relative instanceof IRI)) {

            $relative = new IRI($relative);

        }

        if (!$relative->is_valid()) {

            return false;

        } elseif ($relative->scheme !== null) {

            return clone $relative;

        } else {

            if (!($base instanceof IRI)) {

                $base = new IRI($base);

            }

            if ($base->scheme !== null && $base->is_valid()) {

                if ($relative->get_iri() !== '') {

                    if ($relative->iuserinfo !== null || $relative->ihost !== null || $relative->port !== null) {

                        $target = clone $relative;

                        $target->scheme = $base->scheme;

                    } else {

                        $target = new IRI();

                        $target->scheme = $base->scheme;

                        $target->iuserinfo = $base->iuserinfo;

                        $target->ihost = $base->ihost;

                        $target->port = $base->port;

                        if ($relative->ipath !== '') {

                            if ($relative->ipath[0] === '/') {

                                $target->ipath = $relative->ipath;

                            } elseif (($base->iuserinfo !== null || $base->ihost !== null || $base->port !== null) && $base->ipath === '') {

                                $target->ipath = '/' . $relative->ipath;

                            } elseif (($last_segment = strrpos($base->ipath, '/')) !== false) {

                                $target->ipath = substr($base->ipath, 0, $last_segment + 1) . $relative->ipath;

                            } else {

                                $target->ipath = $relative->ipath;

                            }

                            $target->ipath = $target->remove_dot_segments($target->ipath);

                            $target->iquery = $relative->iquery;

                        } else {

                            $target->ipath = $base->ipath;

                            if ($relative->iquery !== null) {

                                $target->iquery = $relative->iquery;

                            } elseif ($base->iquery !== null) {

                                $target->iquery = $base->iquery;

                            }

                        }

                        $target->ifragment = $relative->ifragment;

                    }

                } else {

                    $target = clone $base;

                    $target->ifragment = null;

                }

                $target->scheme_normalization();

                return $target;

            }

            return false;

        }

    }

    /**

     * Parse an IRI into scheme/authority/path/query/fragment segments

     *

     * @param string $iri

     * @return array

     */

    protected function parse_iri($iri)

    {

        $iri = trim($iri, "\x20\x09\x0A\x0C\x0D");

        if (preg_match('/^((?P<scheme>[^:\/?#]+):)?(\/\/(?P<authority>[^\/?#]*))?(?P<path>[^?#]*)(\?(?P<query>[^#]*))?(#(?P<fragment>.*))?$/', $iri, $match)) {

            if ($match[1] === '') {

                $match['scheme'] = null;

            }

            if (!isset($match[3]) || $match[3] === '') {

                $match['authority'] = null;

            }

            if (!isset($match[5])) {

                $match['path'] = '';

            }

            if (!isset($match[6]) || $match[6] === '') {

                $match['query'] = null;

            }

            if (!isset($match[8]) || $match[8] === '') {

                $match['fragment'] = null;

            }

            return $match;

        }

        // This can occur when a paragraph is accidentally parsed as a URI

        return false;

    }

    /**

     * Remove dot segments from a path

     *

     * @param string $input

     * @return string

     */

    protected function remove_dot_segments($input)

    {

        $output = '';

        while (strpos($input, './') !== false || strpos($input, '/.') !== false || $input === '.' || $input === '..') {

            // A: If the input buffer begins with a prefix of "../" or "./", then remove that prefix from the input buffer; otherwise,

            if (strpos($input, '../') === 0) {

                $input = substr($input, 3);

            } elseif (strpos($input, './') === 0) {

                $input = substr($input, 2);

            }

            // B: if the input buffer begins with a prefix of "/./" or "/.", where "." is a complete path segment, then replace that prefix with "/" in the input buffer; otherwise,

            elseif (strpos($input, '/./') === 0) {

                $input = substr($input, 2);

            } elseif ($input === '/.') {

                $input = '/';

            }

            // C: if the input buffer begins with a prefix of "/../" or "/..", where ".." is a complete path segment, then replace that prefix with "/" in the input buffer and remove the last segment and its preceding "/" (if any) from the output buffer; otherwise,

            elseif (strpos($input, '/../') === 0) {

                $input = substr($input, 3);

                $output = substr_replace($output, '', intval(strrpos($output, '/')));

            } elseif ($input === '/..') {

                $input = '/';

                $output = substr_replace($output, '', intval(strrpos($output, '/')));

            }

            // D: if the input buffer consists only of "." or "..", then remove that from the input buffer; otherwise,

            elseif ($input === '.' || $input === '..') {

                $input = '';

            }

            // E: move the first path segment in the input buffer to the end of the output buffer, including the initial "/" character (if any) and any subsequent characters up to, but not including, the next "/" character or the end of the input buffer

            elseif (($pos = strpos($input, '/', 1)) !== false) {

                $output .= substr($input, 0, $pos);

                $input = substr_replace($input, '', 0, $pos);

            } else {

                $output .= $input;

                $input = '';

            }

        }

        return $output . $input;

    }

    /**

     * Replace invalid character with percent encoding

     *

     * @param string $string Input string

     * @param string $extra_chars Valid characters not in iunreserved or

     *                            iprivate (this is ASCII-only)

     * @param bool $iprivate Allow iprivate

     * @return string

     */

    protected function replace_invalid_with_pct_encoding($string, $extra_chars, $iprivate = false)

    {

        // Normalize as many pct-encoded sections as possible

        $string = preg_replace_callback('/(?:%[A-Fa-f0-9]{2})+/', [$this, 'remove_iunreserved_percent_encoded'], $string);

        // Replace invalid percent characters

        $string = preg_replace('/%(?![A-Fa-f0-9]{2})/', '%25', $string);

        // Add unreserved and % to $extra_chars (the latter is safe because all

        // pct-encoded sections are now valid).

        $extra_chars .= 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-._~%';

        // Now replace any bytes that aren't allowed with their pct-encoded versions

        $position = 0;

        $strlen = strlen($string);

        while (($position += strspn($string, $extra_chars, $position)) < $strlen) {

            $value = ord($string[$position]);

            $character = 0;

            // Start position

            $start = $position;

            // By default we are valid

            $valid = true;

            // No one byte sequences are valid due to the while.

            // Two byte sequence:

            if (($value & 0xE0) === 0xC0) {

                $character = ($value & 0x1F) << 6;

                $length = 2;

                $remaining = 1;

            }

            // Three byte sequence:

            elseif (($value & 0xF0) === 0xE0) {

                $character = ($value & 0x0F) << 12;

                $length = 3;

                $remaining = 2;

            }

            // Four byte sequence:

            elseif (($value & 0xF8) === 0xF0) {

                $character = ($value & 0x07) << 18;

                $length = 4;

                $remaining = 3;

            }

            // Invalid byte:

            else {

                $valid = false;

                $length = 1;

                $remaining = 0;

            }

            if ($remaining) {

                if ($position + $length <= $strlen) {

                    for ($position++; $remaining; $position++) {

                        $value = ord($string[$position]);

                        // Check that the byte is valid, then add it to the character:

                        if (($value & 0xC0) === 0x80) {

                            $character |= ($value & 0x3F) << (--$remaining * 6);

                        }

                        // If it is invalid, count the sequence as invalid and reprocess the current byte:

                        else {

                            $valid = false;

                            $position--;

                            break;

                        }

                    }

                } else {

                    $position = $strlen - 1;

                    $valid = false;

                }

            }

            // Percent encode anything invalid or not in ucschar

            if (

                // Invalid sequences

                !$valid

                // Non-shortest form sequences are invalid

                || $length > 1 && $character <= 0x7F

                || $length > 2 && $character <= 0x7FF

                || $length > 3 && $character <= 0xFFFF

                // Outside of range of ucschar codepoints

                // Noncharacters

                || ($character & 0xFFFE) === 0xFFFE

                || $character >= 0xFDD0 && $character <= 0xFDEF

                || (

                    // Everything else not in ucschar

                    $character > 0xD7FF && $character < 0xF900

                    || $character < 0xA0

                    || $character > 0xEFFFD

                )

                && (

                    // Everything not in iprivate, if it applies

                    !$iprivate

                    || $character < 0xE000

                    || $character > 0x10FFFD

                )

            ) {

                // If we were a character, pretend we weren't, but rather an error.

                if ($valid) {

                    $position--;

                }

                for ($j = $start; $j <= $position; $j++) {

                    $string = substr_replace($string, sprintf('%%%02X', ord($string[$j])), $j, 1);

                    $j += 2;

                    $position += 2;

                    $strlen += 2;

                }

            }

        }

        return $string;

    }

    /**

     * Callback function for preg_replace_callback.

     *

     * Removes sequences of percent encoded bytes that represent UTF-8

     * encoded characters in iunreserved

     *

     * @param array $match PCRE match

     * @return string Replacement

     */

    protected function remove_iunreserved_percent_encoded($match)

    {

        // As we just have valid percent encoded sequences we can just explode

        // and ignore the first member of the returned array (an empty string).

        $bytes = explode('%', $match[0]);

        // Initialize the new string (this is what will be returned) and that

        // there are no bytes remaining in the current sequence (unsurprising

        // at the first byte!).

        $string = '';

        $remaining = 0;

        // these variables will be initialized in the loop but PHPStan is not able to detect it currently

        $start = 0;

        $character = 0;

        $length = 0;

        $valid = true;

        // Loop over each and every byte, and set $value to its value

        for ($i = 1, $len = count($bytes); $i < $len; $i++) {

            $value = hexdec($bytes[$i]);

            // If we're the first byte of sequence:

            if (!$remaining) {

                // Start position

                $start = $i;

                // By default we are valid

                $valid = true;

                // One byte sequence:

                if ($value <= 0x7F) {

                    $character = $value;

                    $length = 1;

                }

                // Two byte sequence:

                elseif (($value & 0xE0) === 0xC0) {

                    $character = ($value & 0x1F) << 6;

                    $length = 2;

                    $remaining = 1;

                }

                // Three byte sequence:

                elseif (($value & 0xF0) === 0xE0) {

                    $character = ($value & 0x0F) << 12;

                    $length = 3;

                    $remaining = 2;

                }

                // Four byte sequence:

                elseif (($value & 0xF8) === 0xF0) {

                    $character = ($value & 0x07) << 18;

                    $length = 4;

                    $remaining = 3;

                }

                // Invalid byte:

                else {

                    $valid = false;

                    $remaining = 0;

                }

            }

            // Continuation byte:

            else {

                // Check that the byte is valid, then add it to the character:

                if (($value & 0xC0) === 0x80) {

                    $remaining--;

                    $character |= ($value & 0x3F) << ($remaining * 6);

                }

                // If it is invalid, count the sequence as invalid and reprocess the current byte as the start of a sequence:

                else {

                    $valid = false;

                    $remaining = 0;

                    $i--;

                }

            }

            // If we've reached the end of the current byte sequence, append it to Unicode::$data

            if (!$remaining) {

                // Percent encode anything invalid or not in iunreserved

                if (

                    // Invalid sequences

                    !$valid

                    // Non-shortest form sequences are invalid

                    || $length > 1 && $character <= 0x7F

                    || $length > 2 && $character <= 0x7FF

                    || $length > 3 && $character <= 0xFFFF

                    // Outside of range of iunreserved codepoints

                    || $character < 0x2D

                    || $character > 0xEFFFD

                    // Noncharacters

                    || ($character & 0xFFFE) === 0xFFFE

                    || $character >= 0xFDD0 && $character <= 0xFDEF

                    // Everything else not in iunreserved (this is all BMP)

                    || $character === 0x2F

                    || $character > 0x39 && $character < 0x41

                    || $character > 0x5A && $character < 0x61

                    || $character > 0x7A && $character < 0x7E

                    || $character > 0x7E && $character < 0xA0

                    || $character > 0xD7FF && $character < 0xF900

                ) {

                    for ($j = $start; $j <= $i; $j++) {

                        $string .= '%' . strtoupper($bytes[$j]);

                    }

                } else {

                    for ($j = $start; $j <= $i; $j++) {

                        $string .= chr(hexdec($bytes[$j]));

                    }

                }

            }

        }

        // If we have any bytes left over they are invalid (i.e., we are

        // mid-way through a multi-byte sequence)

        if ($remaining) {

            for ($j = $start; $j < $len; $j++) {

                $string .= '%' . strtoupper($bytes[$j]);

            }

        }

        return $string;

    }

    protected function scheme_normalization()

    {

        if (isset($this->normalization[$this->scheme]['iuserinfo']) && $this->iuserinfo === $this->normalization[$this->scheme]['iuserinfo']) {

            $this->iuserinfo = null;

        }

        if (isset($this->normalization[$this->scheme]['ihost']) && $this->ihost === $this->normalization[$this->scheme]['ihost']) {

            $this->ihost = null;

        }

        if (isset($this->normalization[$this->scheme]['port']) && $this->port === $this->normalization[$this->scheme]['port']) {

            $this->port = null;

        }

        if (isset($this->normalization[$this->scheme]['ipath']) && $this->ipath === $this->normalization[$this->scheme]['ipath']) {

            $this->ipath = '';

        }

        if (isset($this->normalization[$this->scheme]['iquery']) && $this->iquery === $this->normalization[$this->scheme]['iquery']) {

            $this->iquery = null;

        }

        if (isset($this->normalization[$this->scheme]['ifragment']) && $this->ifragment === $this->normalization[$this->scheme]['ifragment']) {

            $this->ifragment = null;

        }

    }

    /**

     * Check if the object represents a valid IRI. This needs to be done on each

     * call as some things change depending on another part of the IRI.

     *

     * @return bool

     */

    public function is_valid()

    {

        if ($this->ipath === '') {

            return true;

        }

        $isauthority = $this->iuserinfo !== null || $this->ihost !== null ||

            $this->port !== null;

        if ($isauthority && $this->ipath[0] === '/') {

            return true;

        }

        if (!$isauthority && (substr($this->ipath, 0, 2) === '//')) {

            return false;

        }

        // Relative urls cannot have a colon in the first path segment (and the

        // slashes themselves are not included so skip the first character).

        if (!$this->scheme && !$isauthority &&

            strpos($this->ipath, ':') !== false &&

            strpos($this->ipath, '/', 1) !== false &&

            strpos($this->ipath, ':') < strpos($this->ipath, '/', 1)) {

            return false;

        }

        return true;

    }

    /**

     * Set the entire IRI. Returns true on success, false on failure (if there

     * are any invalid characters).

     *

     * @param string $iri

     * @return bool

     */

    public function set_iri($iri, $clear_cache = false)

    {

        static $cache;

        if ($clear_cache) {

            $cache = null;

            return;

        }

        if (!$cache) {

            $cache = [];

        }

        if ($iri === null) {

            return true;

        } elseif (isset($cache[$iri])) {

            [

                $this->scheme,

                $this->iuserinfo,

                $this->ihost,

                $this->port,

                $this->ipath,

                $this->iquery,

                $this->ifragment,

                $return

            ] = $cache[$iri];

            return $return;

        }

        $parsed = $this->parse_iri((string) $iri);

        if (!$parsed) {

            return false;

        }

        $return = $this->set_scheme($parsed['scheme'])

            && $this->set_authority($parsed['authority'])

            && $this->set_path($parsed['path'])

            && $this->set_query($parsed['query'])

            && $this->set_fragment($parsed['fragment']);

        $cache[$iri] = [

            $this->scheme,

            $this->iuserinfo,

            $this->ihost,

            $this->port,

            $this->ipath,

            $this->iquery,

            $this->ifragment,

            $return

        ];

        return $return;

    }

    /**

     * Set the scheme. Returns true on success, false on failure (if there are

     * any invalid characters).

     *

     * @param string $scheme

     * @return bool

     */

    public function set_scheme($scheme)

    {

        if ($scheme === null) {

            $this->scheme = null;

        } elseif (!preg_match('/^[A-Za-z][0-9A-Za-z+\-.]*$/', $scheme)) {

            $this->scheme = null;

            return false;

        } else {

            $this->scheme = strtolower($scheme);

        }

        return true;

    }

    /**

     * Set the authority. Returns true on success, false on failure (if there are

     * any invalid characters).

     *

     * @param string $authority

     * @return bool

     */

    public function set_authority($authority, $clear_cache = false)

    {

        static $cache;

        if ($clear_cache) {

            $cache = null;

            return;

        }

        if (!$cache) {

            $cache = [];

        }

        if ($authority === null) {

            $this->iuserinfo = null;

            $this->ihost = null;

            $this->port = null;

            return true;

        } elseif (isset($cache[$authority])) {

            [

                $this->iuserinfo,

                $this->ihost,

                $this->port,

                $return

            ] = $cache[$authority];

            return $return;

        }

        $remaining = $authority;

        if (($iuserinfo_end = strrpos($remaining, '@')) !== false) {

            $iuserinfo = substr($remaining, 0, $iuserinfo_end);

            $remaining = substr($remaining, $iuserinfo_end + 1);

        } else {

            $iuserinfo = null;

        }

        if (($port_start = strpos($remaining, ':', intval(strpos($remaining, ']')))) !== false) {

            if (($port = substr($remaining, $port_start + 1)) === false) {

                $port = null;

            }

            $remaining = substr($remaining, 0, $port_start);

        } else {

            $port = null;

        }

        $return = $this->set_userinfo($iuserinfo) &&

                  $this->set_host($remaining) &&

                  $this->set_port($port);

        $cache[$authority] = [

            $this->iuserinfo,

            $this->ihost,

            $this->port,

            $return

        ];

        return $return;

    }

    /**

     * Set the iuserinfo.

     *

     * @param string $iuserinfo

     * @return bool

     */

    public function set_userinfo($iuserinfo)

    {

        if ($iuserinfo === null) {

            $this->iuserinfo = null;

        } else {

            $this->iuserinfo = $this->replace_invalid_with_pct_encoding($iuserinfo, '!$&\'()*+,;=:');

            $this->scheme_normalization();

        }

        return true;

    }

    /**

     * Set the ihost. Returns true on success, false on failure (if there are

     * any invalid characters).

     *

     * @param string $ihost

     * @return bool

     */

    public function set_host($ihost)

    {

        if ($ihost === null) {

            $this->ihost = null;

            return true;

        } elseif (substr($ihost, 0, 1) === '[' && substr($ihost, -1) === ']') {

            if (\SimplePie\Net\IPv6::check_ipv6(substr($ihost, 1, -1))) {

                $this->ihost = '[' . \SimplePie\Net\IPv6::compress(substr($ihost, 1, -1)) . ']';

            } else {

                $this->ihost = null;

                return false;

            }

        } else {

            $ihost = $this->replace_invalid_with_pct_encoding($ihost, '!$&\'()*+,;=');

            // Lowercase, but ignore pct-encoded sections (as they should

            // remain uppercase). This must be done after the previous step

            // as that can add unescaped characters.

            $position = 0;

            $strlen = strlen($ihost);

            while (($position += strcspn($ihost, 'ABCDEFGHIJKLMNOPQRSTUVWXYZ%', $position)) < $strlen) {

                if ($ihost[$position] === '%') {

                    $position += 3;

                } else {

                    $ihost[$position] = strtolower($ihost[$position]);

                    $position++;

                }

            }

            $this->ihost = $ihost;

        }

        $this->scheme_normalization();

        return true;

    }

    /**

     * Set the port. Returns true on success, false on failure (if there are

     * any invalid characters).

     *

     * @param string $port

     * @return bool

     */

    public function set_port($port)

    {

        if ($port === null) {

            $this->port = null;

            return true;

        } elseif (strspn($port, '0123456789') === strlen($port)) {

            $this->port = (int) $port;

            $this->scheme_normalization();

            return true;

        }

        $this->port = null;

        return false;

    }

    /**

     * Set the ipath.

     *

     * @param string $ipath

     * @return bool

     */

    public function set_path($ipath, $clear_cache = false)

    {

        static $cache;

        if ($clear_cache) {

            $cache = null;

            return;

        }

        if (!$cache) {

            $cache = [];

        }

        $ipath = (string) $ipath;

        if (isset($cache[$ipath])) {

            $this->ipath = $cache[$ipath][(int) ($this->scheme !== null)];

        } else {

            $valid = $this->replace_invalid_with_pct_encoding($ipath, '!$&\'()*+,;=@:/');

            $removed = $this->remove_dot_segments($valid);

            $cache[$ipath] = [$valid, $removed];

            $this->ipath =  ($this->scheme !== null) ? $removed : $valid;

        }

        $this->scheme_normalization();

        return true;

    }

    /**

     * Set the iquery.

     *

     * @param string $iquery

     * @return bool

     */

    public function set_query($iquery)

    {

        if ($iquery === null) {

            $this->iquery = null;

        } else {

            $this->iquery = $this->replace_invalid_with_pct_encoding($iquery, '!$&\'()*+,;=:@/?', true);

            $this->scheme_normalization();

        }

        return true;

    }

    /**

     * Set the ifragment.

     *

     * @param string $ifragment

     * @return bool

     */

    public function set_fragment($ifragment)

    {

        if ($ifragment === null) {

            $this->ifragment = null;

        } else {

            $this->ifragment = $this->replace_invalid_with_pct_encoding($ifragment, '!$&\'()*+,;=:@/?');

            $this->scheme_normalization();

        }