<?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 an 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
*
* @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 = $filename;
}
// filenameFallback is not ASCII.
if (!preg_match('/^[\x20-\x7e]*$/', $filenameFallback)) {
throw new \InvalidArgumentException('The filename fallback must only contain ASCII characters.');
}
// percent characters aren't safe in fallback.
if (str_contains($filenameFallback, '%')) {
throw new \InvalidArgumentException('The filename fallback cannot contain the "%" character.');
}
// path separators aren't allowed in either.
if (str_contains($filename, '/') || str_contains($filename, '\\') || str_contains($filenameFallback, '/') || str_contains($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, ';');
}
/**
* Like parse_str(), but preserves dots in variable names.
*/
public static function parseQuery(string $query, bool $ignoreBrackets = false, string $separator = '&'): array
{
$q = [];
foreach (explode($separator, $query) as $v) {
if (false !== $i = strpos($v, "\0")) {
$v = substr($v, 0, $i);
}
if (false === $i = strpos($v, '=')) {
$k = urldecode($v);
$v = '';
} else {
$k = urldecode(substr($v, 0, $i));
$v = substr($v, $i);
}
if (false !== $i = strpos($k, "\0")) {
$k = substr($k, 0, $i);
}
$k = ltrim($k, ' ');
if ($ignoreBrackets) {
$q[$k][] = urldecode(substr($v, 1));
continue;
}
if (false === $i = strpos($k, '[')) {
$q[] = bin2hex($k).$v;
} else {
$q[] = bin2hex(substr($k, 0, $i)).rawurlencode(substr($k, $i)).$v;
}
}
if ($ignoreBrackets) {
return $q;
}
parse_str(implode('&', $q), $q);
$query = [];
foreach ($q as $k => $v) {
if (false !== $i = strpos($k, '_')) {
$query[substr_replace($k, hex2bin(substr($k, 0, $i)).'[', 0, 1 + $i)] = $v;
} else {
$query[hex2bin($k)] = $v;
}
}
return $query;
}
private static function groupParts(array $matches, string $separators, bool $first = true): array
{
$separator = $separators[0];
$partSeparators = substr($separators, 1);
$i = 0;
$partMatches = [];
$previousMatchWasSeparator = false;
foreach ($matches as $match) {
if (!$first && $previousMatchWasSeparator && isset($match['separator']) && $match['separator'] === $separator) {
$previousMatchWasSeparator = true;
$partMatches[$i][] = $match;
} elseif (isset($match['separator']) && $match['separator'] === $separator) {
$previousMatchWasSeparator = true;
++$i;
} else {
$previousMatchWasSeparator = false;
$partMatches[$i][] = $match;
}
}
$parts = [];
if ($partSeparators) {
foreach ($partMatches as $matches) {
$parts[] = self::groupParts($matches, $partSeparators, false);
}
} else {
foreach ($partMatches as $matches) {
$parts[] = self::unquote($matches[0][0]);
}
if (!$first && 2 < \count($parts)) {
$parts = [
$parts[0],
implode($separator, \array_slice($parts, 1)),
];
}
}
return $parts;
}
}
Enhancing Payment Security: The Role of Encryption and Tokenization in Digital Transactions
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In the digital age, privacy concerns have become increasingly paramount, prompting the European Union to enact the General Data Protection Regulation (GDPR) in 2018. Among its many provisions, GDPR sets strict guidelines for the collection and processing of personal data, including the use of cookies on websites. Privacy Policy
