Subversion Repositories php-qbpwcf

<?php

/*

 * This file is part of the Symfony package.

 *

 * (c) Fabien Potencier <fabien@symfony.com>

 *

 * For the full copyright and license information, please view the LICENSE

 * file that was distributed with this source code.

 */

namespace Symfony\Component\HttpFoundation;

/**

 * HTTP header utility functions.

 *

 * @author Christian Schmidt <github@chsc.dk>

 */

class HeaderUtils

{

    public const DISPOSITION_ATTACHMENT = 'attachment';

    public const DISPOSITION_INLINE = 'inline';

    /**

     * This class should not be instantiated.

     */

    private function __construct()

    {

    }

    /**

     * Splits an HTTP header by one or more separators.

     *

     * Example:

     *

     *     HeaderUtils::split("da, en-gb;q=0.8", ",;")

     *     // => ['da'], ['en-gb', 'q=0.8']]

     *

     * @param string $separators List of characters to split on, ordered by

     *                           precedence, e.g. ",", ";=", or ",;="

     *

     * @return array Nested array with as many levels as there are characters in

     *               $separators

     */

    public static function split(string $header, string $separators): array

    {

        $quotedSeparators = preg_quote($separators, '/');

        preg_match_all('

            /

                (?!\s)

                    (?:

                        # quoted-string

                        "(?:[^"\\\\]|\\\\.)*(?:"|\\\\|$)

                    |

                        # token

                        [^"'.$quotedSeparators.']+

                    )+

                (?<!\s)

            |

                # separator

                \s*

                (?<separator>['.$quotedSeparators.'])

                \s*

            /x', trim($header), $matches, \PREG_SET_ORDER);

        return self::groupParts($matches, $separators);

    }

    /**

     * Combines an array of arrays into one associative array.

     *

     * Each of the nested arrays should have one or two elements. The first

     * value will be used as the keys in the associative array, and the second

     * will be used as the values, or true if the nested array only contains one

     * element. Array keys are lowercased.

     *

     * Example:

     *

     *     HeaderUtils::combine([["foo", "abc"], ["bar"]])

     *     // => ["foo" => "abc", "bar" => true]

     */

    public static function combine(array $parts): array

    {

        $assoc = [];

        foreach ($parts as $part) {

            $name = strtolower($part[0]);

            $value = $part[1] ?? true;

            $assoc[$name] = $value;

        }

        return $assoc;

    }

    /**

     * Joins an associative array into a string for use in an HTTP header.

     *

     * The key and value of each entry are joined with "=", and all entries

     * are joined with the specified separator and an additional space (for

     * readability). Values are quoted if necessary.

     *

     * Example:

     *

     *     HeaderUtils::toString(["foo" => "abc", "bar" => true, "baz" => "a b c"], ",")

     *     // => 'foo=abc, bar, baz="a b c"'

     */

    public static function toString(array $assoc, string $separator): string

    {

        $parts = [];

        foreach ($assoc as $name => $value) {

            if (true === $value) {

                $parts[] = $name;

            } else {

                $parts[] = $name.'='.self::quote($value);

            }

        }

        return implode($separator.' ', $parts);

    }

    /**

     * Encodes a string as a quoted string, if necessary.

     *

     * If a string contains characters not allowed by the "token" construct in

     * the HTTP specification, it is backslash-escaped and enclosed in quotes

     * to match the "quoted-string" construct.

     */

    public static function quote(string $s): string

    {

        if (preg_match('/^[a-z0-9!#$%&\'*.^_`|~-]+$/i', $s)) {

            return $s;

        }

        return '"'.addcslashes($s, '"\\"').'"';

    }

    /**

     * Decodes a quoted string.

     *

     * If passed an unquoted string that matches the "token" construct (as

     * defined in the HTTP specification), it is passed through verbatimly.

     */

    public static function unquote(string $s): string

    {

        return preg_replace('/\\\\(.)|"/', '$1', $s);

    }

    /**

     * Generates a HTTP Content-Disposition field-value.

     *

     * @param string $disposition      One of "inline" or "attachment"

     * @param string $filename         A unicode string

     * @param string $filenameFallback A string containing only ASCII characters that

     *                                 is semantically equivalent to $filename. If the filename is already ASCII,

     *                                 it can be omitted, or just copied from $filename

     *

     * @return string A string suitable for use as a Content-Disposition field-value

     *

     * @throws \InvalidArgumentException

     *

     * @see RFC 6266

     */

    public static function makeDisposition(string $disposition, string $filename, string $filenameFallback = ''): string

    {

        if (!\in_array($disposition, [self::DISPOSITION_ATTACHMENT, self::DISPOSITION_INLINE])) {

            throw new \InvalidArgumentException(sprintf('The disposition must be either "%s" or "%s".', self::DISPOSITION_ATTACHMENT, self::DISPOSITION_INLINE));

        }

        if ('' === $filenameFallback) {

            $filenameFallback = $filename;

        }

        // filenameFallback is not ASCII.

        if (!preg_match('/^[\x20-\x7e]*$/', $filenameFallback)) {

            throw new \InvalidArgumentException('The filename fallback must only contain ASCII characters.');

        }

        // percent characters aren't safe in fallback.

        if (false !== strpos($filenameFallback, '%')) {

            throw new \InvalidArgumentException('The filename fallback cannot contain the "%" character.');

        }

        // path separators aren't allowed in either.

        if (false !== strpos($filename, '/') || false !== strpos($filename, '\\') || false !== strpos($filenameFallback, '/') || false !== strpos($filenameFallback, '\\')) {

            throw new \InvalidArgumentException('The filename and the fallback cannot contain the "/" and "\\" characters.');

        }

        $params = ['filename' => $filenameFallback];

        if ($filename !== $filenameFallback) {

            $params['filename*'] = "utf-8''".rawurlencode($filename);

        }

        return $disposition.'; '.self::toString($params, ';');

    }

    private static function groupParts(array $matches, string $separators): array

    {

        $separator = $separators[0];

        $partSeparators = substr($separators, 1);

        $i = 0;

        $partMatches = [];

        foreach ($matches as $match) {

            if (isset($match['separator']) && $match['separator'] === $separator) {

                ++$i;

            } else {

                $partMatches[$i][] = $match;

            }

        }

        $parts = [];

        if ($partSeparators) {

            foreach ($partMatches as $matches) {

                $parts[] = self::groupParts($matches, $partSeparators);

            }

        } else {

            foreach ($partMatches as $matches) {

                $parts[] = self::unquote($matches[0][0]);

            }

        }

        return $parts;

    }

}