WordPress/wp-includes/compat.php

125 lines
3.2 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 _($string) {
return $string;
}
}
if ( !function_exists('mb_substr') ):
function mb_substr( $str, $start, $length=null, $encoding=null ) {
return _mb_substr($str, $start, $length, $encoding);
}
endif;
function _mb_substr( $str, $start, $length=null, $encoding=null ) {
// the solution below, works only for utf-8, so in case of a different
// charset, just use built-in substr
$charset = get_option( 'blog_charset' );
if ( !in_array( $charset, array('utf8', 'utf-8', 'UTF8', 'UTF-8') ) ) {
return is_null( $length )? substr( $str, $start ) : substr( $str, $start, $length);
}
// 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( '', $chars );
}
if ( !function_exists('hash_hmac') ):
function hash_hmac($algo, $data, $key, $raw_output = false) {
return _hash_hmac($algo, $data, $key, $raw_output);
}
endif;
function _hash_hmac($algo, $data, $key, $raw_output = 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 ( $raw_output )
return pack( $pack, $hmac );
return $hmac;
}
if ( !function_exists('json_encode') ) {
function json_encode( $string ) {
global $wp_json;
if ( !is_a($wp_json, 'Services_JSON') ) {
require_once( ABSPATH . WPINC . '/class-json.php' );
$wp_json = new Services_JSON();
}
return $wp_json->encodeUnsafe( $string );
}
}
if ( !function_exists('json_decode') ) {
function json_decode( $string, $assoc_array = false ) {
global $wp_json;
if ( !is_a($wp_json, 'Services_JSON') ) {
require_once( ABSPATH . WPINC . '/class-json.php' );
$wp_json = new Services_JSON();
}
$res = $wp_json->decode( $string );
if ( $assoc_array )
$res = _json_decode_object_helper( $res );
return $res;
}
function _json_decode_object_helper($data) {
if ( is_object($data) )
$data = get_object_vars($data);
return is_array($data) ? array_map(__FUNCTION__, $data) : $data;
}
}
if ( ! function_exists( 'hash_equals' ) ) :
/**
* Compare two strings in constant time.
*
* This function was added in PHP 5.6.
* It can leak the length of a string.
*
* @since 3.9.2
*
* @param string $a Expected string.
* @param string $b Actual string.
* @return bool Whether strings are equal.
*/
function hash_equals( $a, $b ) {
$a_length = strlen( $a );
if ( $a_length !== strlen( $b ) ) {
return false;
}
$result = 0;
// Do not attempt to "optimize" this.
for ( $i = 0; $i < $a_length; $i++ ) {
$result |= ord( $a[ $i ] ) ^ ord( $b[ $i ] );
}
return $result === 0;
}
endif;