WordPress/wp-includes/compat.php
John Blackbourn 0c324b983f General: Increase the minimum supported version of PHP to 7.0.0.
This also removes the random compat library which is no longer necessary, and adjusts unit tests and CI workflows that no longer need to take PHP 5.6 into account.

Thank you for your service, PHP 5. Onwards!

Props SergeyBiryukov, mukesh27, dingo_d, audrasjb, jrf, costdev, azaozz, JavierCasares, hellofromTonya, samiamnot, spacedmonkey, masteradhoc, knutsp, garyjones, chanthaboune

Fixes #57345

Built from https://develop.svn.wordpress.org/trunk@56141


git-svn-id: http://core.svn.wordpress.org/trunk@55653 1a063a9b-81f0-0310-95a4-ce76da25c4cd
2023-07-05 17:41:22 +00:00

500 lines
15 KiB
PHP

<?php
/**
* WordPress implementation for PHP functions either missing from older PHP versions or not included by default.
*
* @package PHP
* @access private
*/
// If gettext isn't available.
if ( ! function_exists( '_' ) ) {
function _( $message ) {
return $message;
}
}
/**
* Returns whether PCRE/u (PCRE_UTF8 modifier) is available for use.
*
* @ignore
* @since 4.2.2
* @access private
*
* @param bool $set - Used for testing only
* null : default - get PCRE/u capability
* false : Used for testing - return false for future calls to this function
* 'reset': Used for testing - restore default behavior of this function
*/
function _wp_can_use_pcre_u( $set = null ) {
static $utf8_pcre = 'reset';
if ( null !== $set ) {
$utf8_pcre = $set;
}
if ( 'reset' === $utf8_pcre ) {
// phpcs:ignore WordPress.PHP.NoSilencedErrors.Discouraged -- intentional error generated to detect PCRE/u support.
$utf8_pcre = @preg_match( '/^./u', 'a' );
}
return $utf8_pcre;
}
if ( ! function_exists( 'mb_substr' ) ) :
/**
* Compat function to mimic mb_substr().
*
* @ignore
* @since 3.2.0
*
* @see _mb_substr()
*
* @param string $string The string to extract the substring from.
* @param int $start Position to being extraction from in `$string`.
* @param int|null $length Optional. Maximum number of characters to extract from `$string`.
* Default null.
* @param string|null $encoding Optional. Character encoding to use. Default null.
* @return string Extracted substring.
*/
function mb_substr( $string, $start, $length = null, $encoding = null ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.stringFound
return _mb_substr( $string, $start, $length, $encoding );
}
endif;
/**
* Internal compat function to mimic mb_substr().
*
* Only understands UTF-8 and 8bit. All other character sets will be treated as 8bit.
* For `$encoding === UTF-8`, the `$str` input is expected to be a valid UTF-8 byte
* sequence. The behavior of this function for invalid inputs is undefined.
*
* @ignore
* @since 3.2.0
*
* @param string $str The string to extract the substring from.
* @param int $start Position to being extraction from in `$str`.
* @param int|null $length Optional. Maximum number of characters to extract from `$str`.
* Default null.
* @param string|null $encoding Optional. Character encoding to use. Default null.
* @return string Extracted substring.
*/
function _mb_substr( $str, $start, $length = null, $encoding = null ) {
if ( null === $str ) {
return '';
}
if ( null === $encoding ) {
$encoding = get_option( 'blog_charset' );
}
/*
* The solution below works only for UTF-8, so in case of a different
* charset just use built-in substr().
*/
if ( ! in_array( $encoding, array( 'utf8', 'utf-8', 'UTF8', 'UTF-8' ), true ) ) {
return is_null( $length ) ? substr( $str, $start ) : substr( $str, $start, $length );
}
if ( _wp_can_use_pcre_u() ) {
// Use the regex unicode support to separate the UTF-8 characters into an array.
preg_match_all( '/./us', $str, $match );
$chars = is_null( $length ) ? array_slice( $match[0], $start ) : array_slice( $match[0], $start, $length );
return implode( '', $chars );
}
$regex = '/(
[\x00-\x7F] # single-byte sequences 0xxxxxxx
| [\xC2-\xDF][\x80-\xBF] # double-byte sequences 110xxxxx 10xxxxxx
| \xE0[\xA0-\xBF][\x80-\xBF] # triple-byte sequences 1110xxxx 10xxxxxx * 2
| [\xE1-\xEC][\x80-\xBF]{2}
| \xED[\x80-\x9F][\x80-\xBF]
| [\xEE-\xEF][\x80-\xBF]{2}
| \xF0[\x90-\xBF][\x80-\xBF]{2} # four-byte sequences 11110xxx 10xxxxxx * 3
| [\xF1-\xF3][\x80-\xBF]{3}
| \xF4[\x80-\x8F][\x80-\xBF]{2}
)/x';
// Start with 1 element instead of 0 since the first thing we do is pop.
$chars = array( '' );
do {
// We had some string left over from the last round, but we counted it in that last round.
array_pop( $chars );
/*
* Split by UTF-8 character, limit to 1000 characters (last array element will contain
* the rest of the string).
*/
$pieces = preg_split( $regex, $str, 1000, PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_NO_EMPTY );
$chars = array_merge( $chars, $pieces );
// If there's anything left over, repeat the loop.
} while ( count( $pieces ) > 1 && $str = array_pop( $pieces ) );
return implode( '', array_slice( $chars, $start, $length ) );
}
if ( ! function_exists( 'mb_strlen' ) ) :
/**
* Compat function to mimic mb_strlen().
*
* @ignore
* @since 4.2.0
*
* @see _mb_strlen()
*
* @param string $string The string to retrieve the character length from.
* @param string|null $encoding Optional. Character encoding to use. Default null.
* @return int String length of `$string`.
*/
function mb_strlen( $string, $encoding = null ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.stringFound
return _mb_strlen( $string, $encoding );
}
endif;
/**
* Internal compat function to mimic mb_strlen().
*
* Only understands UTF-8 and 8bit. All other character sets will be treated as 8bit.
* For `$encoding === UTF-8`, the `$str` input is expected to be a valid UTF-8 byte
* sequence. The behavior of this function for invalid inputs is undefined.
*
* @ignore
* @since 4.2.0
*
* @param string $str The string to retrieve the character length from.
* @param string|null $encoding Optional. Character encoding to use. Default null.
* @return int String length of `$str`.
*/
function _mb_strlen( $str, $encoding = null ) {
if ( null === $encoding ) {
$encoding = get_option( 'blog_charset' );
}
/*
* The solution below works only for UTF-8, so in case of a different charset
* just use built-in strlen().
*/
if ( ! in_array( $encoding, array( 'utf8', 'utf-8', 'UTF8', 'UTF-8' ), true ) ) {
return strlen( $str );
}
if ( _wp_can_use_pcre_u() ) {
// Use the regex unicode support to separate the UTF-8 characters into an array.
preg_match_all( '/./us', $str, $match );
return count( $match[0] );
}
$regex = '/(?:
[\x00-\x7F] # single-byte sequences 0xxxxxxx
| [\xC2-\xDF][\x80-\xBF] # double-byte sequences 110xxxxx 10xxxxxx
| \xE0[\xA0-\xBF][\x80-\xBF] # triple-byte sequences 1110xxxx 10xxxxxx * 2
| [\xE1-\xEC][\x80-\xBF]{2}
| \xED[\x80-\x9F][\x80-\xBF]
| [\xEE-\xEF][\x80-\xBF]{2}
| \xF0[\x90-\xBF][\x80-\xBF]{2} # four-byte sequences 11110xxx 10xxxxxx * 3
| [\xF1-\xF3][\x80-\xBF]{3}
| \xF4[\x80-\x8F][\x80-\xBF]{2}
)/x';
// Start at 1 instead of 0 since the first thing we do is decrement.
$count = 1;
do {
// We had some string left over from the last round, but we counted it in that last round.
$count--;
/*
* Split by UTF-8 character, limit to 1000 characters (last array element will contain
* the rest of the string).
*/
$pieces = preg_split( $regex, $str, 1000 );
// Increment.
$count += count( $pieces );
// If there's anything left over, repeat the loop.
} while ( $str = array_pop( $pieces ) );
// Fencepost: preg_split() always returns one extra item in the array.
return --$count;
}
if ( ! function_exists( 'hash_hmac' ) ) :
/**
* Compat function to mimic hash_hmac().
*
* The Hash extension is bundled with PHP by default since PHP 5.1.2.
* However, the extension may be explicitly disabled on select servers.
* As of PHP 7.4.0, the Hash extension is a core PHP extension and can no
* longer be disabled.
* I.e. when PHP 7.4.0 becomes the minimum requirement, this polyfill
* and the associated `_hash_hmac()` function can be safely removed.
*
* @ignore
* @since 3.2.0
*
* @see _hash_hmac()
*
* @param string $algo Hash algorithm. Accepts 'md5' or 'sha1'.
* @param string $data Data to be hashed.
* @param string $key Secret key to use for generating the hash.
* @param bool $binary Optional. Whether to output raw binary data (true),
* or lowercase hexits (false). Default false.
* @return string|false The hash in output determined by `$binary`.
* False if `$algo` is unknown or invalid.
*/
function hash_hmac( $algo, $data, $key, $binary = false ) {
return _hash_hmac( $algo, $data, $key, $binary );
}
endif;
/**
* Internal compat function to mimic hash_hmac().
*
* @ignore
* @since 3.2.0
*
* @param string $algo Hash algorithm. Accepts 'md5' or 'sha1'.
* @param string $data Data to be hashed.
* @param string $key Secret key to use for generating the hash.
* @param bool $binary Optional. Whether to output raw binary data (true),
* or lowercase hexits (false). Default false.
* @return string|false The hash in output determined by `$binary`.
* False if `$algo` is unknown or invalid.
*/
function _hash_hmac( $algo, $data, $key, $binary = false ) {
$packs = array(
'md5' => 'H32',
'sha1' => 'H40',
);
if ( ! isset( $packs[ $algo ] ) ) {
return false;
}
$pack = $packs[ $algo ];
if ( strlen( $key ) > 64 ) {
$key = pack( $pack, $algo( $key ) );
}
$key = str_pad( $key, 64, chr( 0 ) );
$ipad = ( substr( $key, 0, 64 ) ^ str_repeat( chr( 0x36 ), 64 ) );
$opad = ( substr( $key, 0, 64 ) ^ str_repeat( chr( 0x5C ), 64 ) );
$hmac = $algo( $opad . pack( $pack, $algo( $ipad . $data ) ) );
if ( $binary ) {
return pack( $pack, $hmac );
}
return $hmac;
}
if ( ! function_exists( 'hash_equals' ) ) :
/**
* Timing attack safe string comparison.
*
* Compares two strings using the same time whether they're equal or not.
*
* Note: It can leak the length of a string when arguments of differing length are supplied.
*
* This function was added in PHP 5.6.
* However, the Hash extension may be explicitly disabled on select servers.
* As of PHP 7.4.0, the Hash extension is a core PHP extension and can no
* longer be disabled.
* I.e. when PHP 7.4.0 becomes the minimum requirement, this polyfill
* can be safely removed.
*
* @since 3.9.2
*
* @param string $known_string Expected string.
* @param string $user_string Actual, user supplied, string.
* @return bool Whether strings are equal.
*/
function hash_equals( $known_string, $user_string ) {
$known_string_length = strlen( $known_string );
if ( strlen( $user_string ) !== $known_string_length ) {
return false;
}
$result = 0;
// Do not attempt to "optimize" this.
for ( $i = 0; $i < $known_string_length; $i++ ) {
$result |= ord( $known_string[ $i ] ) ^ ord( $user_string[ $i ] );
}
return 0 === $result;
}
endif;
// sodium_crypto_box() was introduced in PHP 7.2.
if ( ! function_exists( 'sodium_crypto_box' ) ) {
require ABSPATH . WPINC . '/sodium_compat/autoload.php';
}
if ( ! function_exists( 'is_countable' ) ) {
/**
* Polyfill for is_countable() function added in PHP 7.3.
*
* Verify that the content of a variable is an array or an object
* implementing the Countable interface.
*
* @since 4.9.6
*
* @param mixed $value The value to check.
* @return bool True if `$value` is countable, false otherwise.
*/
function is_countable( $value ) {
return ( is_array( $value )
|| $value instanceof Countable
|| $value instanceof SimpleXMLElement
|| $value instanceof ResourceBundle
);
}
}
if ( ! function_exists( 'is_iterable' ) ) {
/**
* Polyfill for is_iterable() function added in PHP 7.1.
*
* Verify that the content of a variable is an array or an object
* implementing the Traversable interface.
*
* @since 4.9.6
*
* @param mixed $value The value to check.
* @return bool True if `$value` is iterable, false otherwise.
*/
function is_iterable( $value ) {
return ( is_array( $value ) || $value instanceof Traversable );
}
}
if ( ! function_exists( 'array_key_first' ) ) {
/**
* Polyfill for array_key_first() function added in PHP 7.3.
*
* Get the first key of the given array without affecting
* the internal array pointer.
*
* @since 5.9.0
*
* @param array $array An array.
* @return string|int|null The first key of array if the array
* is not empty; `null` otherwise.
*/
function array_key_first( array $array ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
foreach ( $array as $key => $value ) {
return $key;
}
}
}
if ( ! function_exists( 'array_key_last' ) ) {
/**
* Polyfill for `array_key_last()` function added in PHP 7.3.
*
* Get the last key of the given array without affecting the
* internal array pointer.
*
* @since 5.9.0
*
* @param array $array An array.
* @return string|int|null The last key of array if the array
*. is not empty; `null` otherwise.
*/
function array_key_last( array $array ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
if ( empty( $array ) ) {
return null;
}
end( $array );
return key( $array );
}
}
if ( ! function_exists( 'str_contains' ) ) {
/**
* Polyfill for `str_contains()` function added in PHP 8.0.
*
* Performs a case-sensitive check indicating if needle is
* contained in haystack.
*
* @since 5.9.0
*
* @param string $haystack The string to search in.
* @param string $needle The substring to search for in the `$haystack`.
* @return bool True if `$needle` is in `$haystack`, otherwise false.
*/
function str_contains( $haystack, $needle ) {
if ( '' === $needle ) {
return true;
}
return false !== strpos( $haystack, $needle );
}
}
if ( ! function_exists( 'str_starts_with' ) ) {
/**
* Polyfill for `str_starts_with()` function added in PHP 8.0.
*
* Performs a case-sensitive check indicating if
* the haystack begins with needle.
*
* @since 5.9.0
*
* @param string $haystack The string to search in.
* @param string $needle The substring to search for in the `$haystack`.
* @return bool True if `$haystack` starts with `$needle`, otherwise false.
*/
function str_starts_with( $haystack, $needle ) {
if ( '' === $needle ) {
return true;
}
return 0 === strpos( $haystack, $needle );
}
}
if ( ! function_exists( 'str_ends_with' ) ) {
/**
* Polyfill for `str_ends_with()` function added in PHP 8.0.
*
* Performs a case-sensitive check indicating if
* the haystack ends with needle.
*
* @since 5.9.0
*
* @param string $haystack The string to search in.
* @param string $needle The substring to search for in the `$haystack`.
* @return bool True if `$haystack` ends with `$needle`, otherwise false.
*/
function str_ends_with( $haystack, $needle ) {
if ( '' === $haystack ) {
return '' === $needle;
}
$len = strlen( $needle );
return substr( $haystack, -$len, $len ) === $needle;
}
}
// IMAGETYPE_WEBP constant is only defined in PHP 7.1 or later.
if ( ! defined( 'IMAGETYPE_WEBP' ) ) {
define( 'IMAGETYPE_WEBP', 18 );
}
// IMG_WEBP constant is only defined in PHP 7.0.10 or later.
if ( ! defined( 'IMG_WEBP' ) ) {
define( 'IMG_WEBP', IMAGETYPE_WEBP );
}