<?php
/**
* WordPress implementation for PHP functions either missing from older PHP versions or not included by default.
*
* This file is loaded extremely early and the functions can be relied upon by drop-ins.
* Ergo, please ensure you do not rely on external functions when writing code for this file.
* Only use functions built into PHP or are defined in this file and have adequate testing
* and error suppression to ensure the file will run correctly and not break websites.
*
* @package PHP
* @access private
*/
// If gettext isn't available.
if ( ! function_exists( '_' ) ) {
/**
* Compat function to mimic _(), an alias of gettext().
*
* @since 0.71
*
* @see https://php.net/manual/en/function.gettext.php
*
* @param string $message The message being translated.
* @return string
*/
function _( $message ) {
return $message;
}
}
/**
* Returns whether PCRE/u (PCRE_UTF8 modifier) is available for use.
*
* @ignore
* @since 4.2.2
* @since 6.9.0 Deprecated the `$set` argument.
* @access private
*
* @param bool $set Deprecated. This argument is no longer used for testing purposes.
*/
function _wp_can_use_pcre_u( $set = null ) {
static $utf8_pcre = null;
if ( isset( $set ) ) {
_deprecated_argument( __FUNCTION__, '6.9.0' );
}
if ( isset( $utf8_pcre ) ) {
return $utf8_pcre;
}
$utf8_pcre = true;
set_error_handler(
function ( $errno, $errstr ) use ( &$utf8_pcre ) {
if ( str_starts_with( $errstr, 'preg_match():' ) ) {
$utf8_pcre = false;
return true;
}
return false;
},
E_WARNING
);
/*
* Attempt to compile a PCRE pattern with the PCRE_UTF8 flag. For
* systems lacking Unicode support this will trigger a warning
* during compilation, which the error handler will intercept.
*/
preg_match( '//u', '' );
restore_error_handler();
return $utf8_pcre;
}
/**
* Indicates if a given slug for a character set represents the UTF-8 text encoding.
*
* A charset is considered to represent UTF-8 if it is a case-insensitive match
* of "UTF-8" with or without the hyphen.
*
* Example:
*
* true === _is_utf8_charset( 'UTF-8' );
* true === _is_utf8_charset( 'utf8' );
* false === _is_utf8_charset( 'latin1' );
* false === _is_utf8_charset( 'UTF 8' );
*
* // Only strings match.
* false === _is_utf8_charset( [ 'charset' => 'utf-8' ] );
*
* `is_utf8_charset` should be used outside of this file.
*
* @ignore
* @since 6.6.1
*
* @param string $charset_slug Slug representing a text character encoding, or "charset".
* E.g. "UTF-8", "Windows-1252", "ISO-8859-1", "SJIS".
*
* @return bool Whether the slug represents the UTF-8 encoding.
*/
function _is_utf8_charset( $charset_slug ) {
if ( ! is_string( $charset_slug ) ) {
return false;
}
return (
0 === strcasecmp( 'UTF-8', $charset_slug ) ||
0 === strcasecmp( 'UTF8', $charset_slug )
);
}
if ( ! function_exists( 'mb_chr' ) ) :
/**
* Compat function to mimic mb_chr().
*
* @ignore
* @since 7.1.0
*
* @see _mb_ord()
*
* @param int $codepoint A Unicode codepoint value, e.g. 128024 for U+1F418 ELEPHANT
* @param "UTF-8"|null $encoding Must be 'UTF-8' or null.
* @return string|false A string containing the requested character, if it can be represented in the specified encoding or false on failure.
*/
function mb_chr( $codepoint, $encoding = null ) {
return _mb_chr( $codepoint, $encoding );
}
endif;
/**
* Internal compat function to mimic mb_chr().
*
* @ignore
* @since 7.1.0
*
* @param int $codepoint A Unicode codepoint value, e.g. 128024 for U+1F418 ELEPHANT
* @param "UTF-8"|null $encoding Must be 'UTF-8' or null.
* @return string|false A string containing the requested character, if it can be represented in the specified encoding or false on failure.
*/
function _mb_chr( $codepoint, $encoding = null ) {
if ( ! is_int( $codepoint ) || ( isset( $encoding ) && 'UTF-8' !== $encoding ) ) {
return false;
}
// Pre-check to ensure a valid code point.
if (
$codepoint < 0 ||
( $codepoint >= 0xD800 && $codepoint <= 0xDFFF ) ||
$codepoint > 0x10FFFF
) {
return false;
}
if ( $codepoint <= 0x7F ) {
return chr( $codepoint );
}
if ( $codepoint <= 0x7FF ) {
$byte1 = chr( ( $codepoint >> 6 ) | 0xC0 );
$byte2 = chr( $codepoint & 0x3F | 0x80 );
return "{$byte1}{$byte2}";
}
if ( $codepoint <= 0xFFFF ) {
$byte1 = chr( ( $codepoint >> 12 ) | 0xE0 );
$byte2 = chr( ( $codepoint >> 6 ) & 0x3F | 0x80 );
$byte3 = chr( $codepoint & 0x3F | 0x80 );
return "{$byte1}{$byte2}{$byte3}";
}
// Any values above U+10FFFF are eliminated above in the pre-check.
$byte1 = chr( ( $codepoint >> 18 ) | 0xF0 );
$byte2 = chr( ( $codepoint >> 12 ) & 0x3F | 0x80 );
$byte3 = chr( ( $codepoint >> 6 ) & 0x3F | 0x80 );
$byte4 = chr( $codepoint & 0x3F | 0x80 );
return "{$byte1}{$byte2}{$byte3}{$byte4}";
}
if ( ! function_exists( 'mb_ord' ) ) :
/**
* Compat function to mimic mb_ord().
*
* @ignore
* @since 7.1.0
*
* @see _mb_ord()
*
* @param string $string Return the code point at the start of this string.
* @param "UTF-8"|null $encoding Must be 'UTF-8' or null.
* @return int|false The Unicode code point for the first character of string or false on failure.
*/
function mb_ord( $string, $encoding = null ) {
return _mb_ord( $string, $encoding );
}
endif;
/**
* Internal compat function to mimic mb_ord().
*
* @ignore
* @since 7.1.0
*
* @param string $string Return the code point at the start of this string.
* @param "UTF-8"|null $encoding Must be 'UTF-8' or null.
* @return int|false The Unicode code point for the first character of string or false on failure.
*/
function _mb_ord( $string, $encoding = null ) {
if ( ! is_string( $string ) || '' === $string || ( isset( $encoding ) && 'UTF-8' !== $encoding ) ) {
return false;
}
$byte_length = 0;
$invalid_length = 0;
$found_count = _wp_scan_utf8( $string, $byte_length, $invalid_length, null, 1 );
if ( 1 !== $found_count ) {
return false;
}
// These are valid code points, so no further validation is required.
$b0 = ord( $string[0] );
switch ( $byte_length ) {
case 1:
return $b0;
case 2:
return (
( ( $b0 & 0x1F ) << 6 ) |
( ( ord( $string[1] ) & 0x3F ) )
);
case 3:
return (
( ( $b0 & 0x0F ) << 12 ) |
( ( ord( $string[1] ) & 0x3F ) << 6 ) |
( ( ord( $string[2] ) & 0x3F ) )
);
case 4:
return (
( ( $b0 & 0x07 ) << 18 ) |
( ( ord( $string[1] ) & 0x3F ) << 12 ) |
( ( ord( $string[2] ) & 0x3F ) << 6 ) |
( ( ord( $string[3] ) & 0x3F ) )
);
}
return false;
}
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 supports UTF-8 and non-shifting single-byte encodings. For all other encodings
* expect the substrings to be misaligned. When the given encoding (or the `blog_charset`
* if none is provided) isn’t UTF-8 then the function returns the output of {@see \substr()}.
*
* @ignore
* @since 3.2.0
*
* @param string $str The string to extract the substring from.
* @param int $start Character offset at which to start the substring extraction.
* @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 '';
}
// The solution below works only for UTF-8; treat all other encodings as byte streams.
if ( ! _is_utf8_charset( $encoding ?? get_option( 'blog_charset' ) ) ) {
$result = is_null( $length ) ? substr( $str, $start ) : substr( $str, $start, $length );
/*
* For an out-of-range start, substr() returns false on PHP < 8.0 but an
* empty string on PHP >= 8.0. mb_substr() always returns an empty string,
* so normalize to match its behavior across all supported PHP versions.
*/
return false === $result ? '' : $result;
}
$total_length = ( $start < 0 || $length < 0 )
? _wp_utf8_codepoint_count( $str )
: 0;
$normalized_start = $start < 0
? max( 0, $total_length + $start )
: $start;
/*
* The starting offset is provided as characters, which means this needs to
* find how many bytes that many characters occupies at the start of the string.
*/
$starting_byte_offset = _wp_utf8_codepoint_span( $str, 0, $normalized_start );
$normalized_length = $length < 0
? max( 0, $total_length - $normalized_start + $length )
: $length;
/*
* This is the main step. It finds how many bytes the given length of code points
* occupies in the input, starting at the byte offset calculated above.
*/
$byte_length = isset( $normalized_length )
? _wp_utf8_codepoint_span( $str, $starting_byte_offset, $normalized_length )
: ( strlen( $str ) - $starting_byte_offset );
// The result is a normal byte-level substring using the computed ranges.
return substr( $str, $starting_byte_offset, $byte_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 supports UTF-8 and non-shifting single-byte encodings. For all other
* encodings expect the counts to be wrong. When the given encoding (or the
* `blog_charset` if none is provided) isn’t UTF-8 then the function returns
* the byte-count of the provided string.
*
* @ignore
* @since 4.2.0
*
* @param string $str The string to retrieve the character length from.
* @param string|null $encoding Optional. Count characters according to this encoding.
* Default is to consult `blog_charset`.
* @return int Count of code points if UTF-8, byte length otherwise.
*/
function _mb_strlen( $str, $encoding = null ) {
return _is_utf8_charset( $encoding ?? get_option( 'blog_charset' ) )
? _wp_utf8_codepoint_count( $str )
: strlen( $str );
}
if ( ! function_exists( 'utf8_encode' ) ) :
if ( extension_loaded( 'mbstring' ) ) :
/**
* Converts a string from ISO-8859-1 to UTF-8.
*
* @deprecated Use {@see \mb_convert_encoding()} instead.
*
* @since 6.9.0
*
* @param string $iso_8859_1_text Text treated as ISO-8859-1 (latin1) bytes.
* @return string Text converted into a UTF-8.
*/
function utf8_encode( $iso_8859_1_text ): string {
_deprecated_function( __FUNCTION__, '6.9.0', 'mb_convert_encoding' );
return mb_convert_encoding( $iso_8859_1_text, 'UTF-8', 'ISO-8859-1' );
}
else :
/**
* @ignore
* @private
*
* @since 6.9.0
*/
function utf8_encode( $iso_8859_1_text ): string {
_deprecated_function( __FUNCTION__, '6.9.0', 'mb_convert_encoding' );
return _wp_utf8_encode_fallback( $iso_8859_1_text );
}
endif;
endif;
if ( ! function_exists( 'utf8_decode' ) ) :
if ( extension_loaded( 'mbstring' ) ) :
/**
* Converts a string from UTF-8 to ISO-8859-1.
*
* @deprecated Use {@see \mb_convert_encoding()} instead.
*
* @since 6.9.0
*
* @param string $utf8_text Text treated as UTF-8.
* @return string Text converted into ISO-8859-1.
*/
function utf8_decode( $utf8_text ): string {
_deprecated_function( __FUNCTION__, '6.9.0', 'mb_convert_encoding' );
return mb_convert_encoding( $utf8_text, 'ISO-8859-1', 'UTF-8' );
}
else :
/**
* @ignore
* @private
*
* @since 6.9.0
*/
function utf8_decode( $utf8_text ): string {
_deprecated_function( __FUNCTION__, '6.9.0', 'mb_convert_encoding' );
return _wp_utf8_decode_fallback( $utf8_text );
}
endif;
endif;
// sodium_crypto_box() was introduced with Sodium in PHP 7.2, but the extension may not be enabled.
if ( ! function_exists( 'sodium_crypto_box' ) ) {
require ABSPATH . WPINC . '/sodium_compat/autoload.php';
}
if ( ! function_exists( 'array_is_list' ) ) {
/**
* Polyfill for `array_is_list()` function added in PHP 8.1.
*
* Determines if the given array is a list.
*
* An array is considered a list if its keys consist of consecutive numbers from 0 to count($array)-1.
*
* @see https://github.com/symfony/polyfill-php81/tree/main
*
* @since 6.5.0
*
* @param array<mixed> $arr The array being evaluated.
* @return bool True if array is a list, false otherwise.
*/
function array_is_list( $arr ) {
if ( ( array() === $arr ) || ( array_values( $arr ) === $arr ) ) {
return true;
}
$next_key = -1;
foreach ( $arr as $k => $v ) {
if ( ++$next_key !== $k ) {
return false;
}
}
return true;
}
}
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;
}
}
if ( ! function_exists( 'array_find' ) ) {
/**
* Polyfill for `array_find()` function added in PHP 8.4.
*
* Searches an array for the first element that passes a given callback.
*
* @since 6.8.0
*
* @param array $array The array to search.
* @param callable $callback The callback to run for each element.
* @return mixed|null The first element in the array that passes the `$callback`, otherwise null.
*/
function array_find( array $array, callable $callback ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
foreach ( $array as $key => $value ) {
if ( $callback( $value, $key ) ) {
return $value;
}
}
return null;
}
}
if ( ! function_exists( 'array_find_key' ) ) {
/**
* Polyfill for `array_find_key()` function added in PHP 8.4.
*
* Searches an array for the first key that passes a given callback.
*
* @since 6.8.0
*
* @param array $array The array to search.
* @param callable $callback The callback to run for each element.
* @return int|string|null The first key in the array that passes the `$callback`, otherwise null.
*/
function array_find_key( array $array, callable $callback ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
foreach ( $array as $key => $value ) {
if ( $callback( $value, $key ) ) {
return $key;
}
}
return null;
}
}
if ( ! function_exists( 'array_any' ) ) {
/**
* Polyfill for `array_any()` function added in PHP 8.4.
*
* Checks if any element of an array passes a given callback.
*
* @since 6.8.0
*
* @param array $array The array to check.
* @param callable $callback The callback to run for each element.
* @return bool True if any element in the array passes the `$callback`, otherwise false.
*/
function array_any( array $array, callable $callback ): bool { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
foreach ( $array as $key => $value ) {
if ( $callback( $value, $key ) ) {
return true;
}
}
return false;
}
}
if ( ! function_exists( 'array_all' ) ) {
/**
* Polyfill for `array_all()` function added in PHP 8.4.
*
* Checks if all elements of an array pass a given callback.
*
* @since 6.8.0
*
* @param array $array The array to check.
* @param callable $callback The callback to run for each element.
* @return bool True if all elements in the array pass the `$callback`, otherwise false.
*/
function array_all( array $array, callable $callback ): bool { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
foreach ( $array as $key => $value ) {
if ( ! $callback( $value, $key ) ) {
return false;
}
}
return true;
}
}
if ( ! function_exists( 'array_first' ) ) {
/**
* Polyfill for `array_first()` function added in PHP 8.5.
*
* Returns the first element of an array.
*
* @since 6.9.0
*
* @param array $array The array to get the first element from.
* @return mixed|null The first element of the array, or null if the array is empty.
*/
function array_first( array $array ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
if ( empty( $array ) ) {
return null;
}
foreach ( $array as $value ) {
return $value;
}
}
}
if ( ! function_exists( 'array_last' ) ) {
/**
* Polyfill for `array_last()` function added in PHP 8.5.
*
* Returns the last element of an array.
*
* @since 6.9.0
*
* @param array $array The array to get the last element from.
* @return mixed|null The last element of the array, or null if the array is empty.
*/
function array_last( array $array ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.arrayFound
if ( empty( $array ) ) {
return null;
}
return $array[ array_key_last( $array ) ];
}
}
if ( ! function_exists( 'clamp' ) ) {
/**
* Polyfill for `clamp()` function added in PHP 8.6.
*
* Clamps a value to be within the range of a given minimum and maximum.
*
* If the value is within the bounds, the original value is returned.
* If it is not within the bounds, the closest bound is returned.
*
* @since 7.1.0
*
* @param mixed $value The value to clamp.
* @param mixed $min The minimum bound. Must be less than or equal to `$max`.
* @param mixed $max The maximum bound. Must be greater than or equal to `$min`.
* @return mixed The clamped value. Either `$value`, `$min`, or `$max`.
*
* @throws ValueError If `$min` is greater than `$max`, or if `$min` or `$max` is NAN, and the ValueError class exists (PHP 8.0+ or polyfilled).
* @throws InvalidArgumentException If `$min` is greater than `$max`, or if `$min` or `$max` is NAN, and the ValueError class does not exist (PHP 7.x).
*
* @phpstan-template TValue
* @phpstan-template TMin
* @phpstan-template TMax
* @phpstan-param TValue $value
* @phpstan-param TMin $min
* @phpstan-param TMax $max
* @phpstan-return TValue|TMin|TMax
*/
function clamp( $value, $min, $max ) {
$throw_value_error = static function ( string $message ) {
// The ValueError class was introduced in PHP 8, so in 7.4 throw InvalidArgumentException instead.
if ( ! class_exists( 'ValueError', false ) ) {
throw new InvalidArgumentException( $message );
}
throw new ValueError( $message );
};
if ( is_float( $min ) && is_nan( $min ) ) {
$throw_value_error( 'clamp(): Argument #2 ($min) must not be NAN' );
}
if ( is_float( $max ) && is_nan( $max ) ) {
$throw_value_error( 'clamp(): Argument #3 ($max) must not be NAN' );
}
if ( $max < $min ) {
$throw_value_error( 'clamp(): Argument #2 ($min) must be smaller than or equal to argument #3 ($max)' );
}
/*
* The upper bound is checked before the lower bound to match the order in PHP's
* implementation. Comparison in PHP is not transitive when operands of different
* types are mixed (for example, comparing against a bool coerces both operands to
* bool), so both bounds can compare as exceeded at once, and the first check wins.
*/
if ( $value > $max ) {
return $max;
}
if ( $value < $min ) {
return $min;
}
return $value;
}
}
// IMAGETYPE_AVIF constant is only defined in PHP 8.x or later.
if ( ! defined( 'IMAGETYPE_AVIF' ) ) {
define( 'IMAGETYPE_AVIF', 19 );
}
// IMG_AVIF constant is only defined in PHP 8.x or later.
if ( ! defined( 'IMG_AVIF' ) ) {
define( 'IMG_AVIF', IMAGETYPE_AVIF );
}
// IMAGETYPE_HEIF constant is only defined in PHP 8.5 or later.
if ( ! defined( 'IMAGETYPE_HEIF' ) ) {
define( 'IMAGETYPE_HEIF', 20 );
}