www.gusucode.com > wordpress PHP博客系统英文版 v4.5.1PHP源码程序 > wordpress PHP博客系统英文版 v4.5.1/wordpress/wordpress/wp-includes/compat.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;
}
}
/**
* Returns whether PCRE/u (PCRE_UTF8 modifier) is available for use.
*
* @ignore
* @since 4.2.2
* @access private
*
* @staticvar string $utf8_pcre
*
* @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 ) {
$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 $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 ) {
return _mb_substr( $str, $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 === $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' ) ) ) {
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 join( '', 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 $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 ) {
return _mb_strlen( $str, $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' ) ) ) {
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().
*
* @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 $raw_output Optional. Whether to output raw binary data (true),
* or lowercase hexits (false). Default false.
* @return string|false The hash in output determined by `$raw_output`. False if `$algo`
* is unknown or invalid.
*/
function hash_hmac($algo, $data, $key, $raw_output = false) {
return _hash_hmac($algo, $data, $key, $raw_output);
}
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 $raw_output Optional. Whether to output raw binary data (true),
* or lowercase hexits (false). Default false.
* @return string|false The hash in output determined by `$raw_output`. False if `$algo`
* is unknown or invalid.
*/
function _hash_hmac($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 ( ! ( $wp_json instanceof Services_JSON ) ) {
require_once( ABSPATH . WPINC . '/class-json.php' );
$wp_json = new Services_JSON();
}
return $wp_json->encodeUnsafe( $string );
}
}
if ( !function_exists('json_decode') ) {
/**
* @global Services_JSON $wp_json
* @param string $string
* @param bool $assoc_array
* @return object|array
*/
function json_decode( $string, $assoc_array = false ) {
global $wp_json;
if ( ! ($wp_json instanceof 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;
}
/**
* @param object $data
* @return array
*/
function _json_decode_object_helper($data) {
if ( is_object($data) )
$data = get_object_vars($data);
return is_array($data) ? array_map(__FUNCTION__, $data) : $data;
}
}
if ( ! function_exists( 'hash_equals' ) ) :
/**
* Timing attack safe string comparison
*
* Compares two strings using the same time whether they're equal or not.
*
* This function was added in PHP 5.6.
*
* Note: It can leak the length of a string when arguments of differing length are supplied.
*
* @since 3.9.2
*
* @param string $a Expected string.
* @param string $b Actual, user supplied, 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;
// JSON_PRETTY_PRINT was introduced in PHP 5.4
// Defined here to prevent a notice when using it with wp_json_encode()
if ( ! defined( 'JSON_PRETTY_PRINT' ) ) {
define( 'JSON_PRETTY_PRINT', 128 );
}
if ( ! function_exists( 'json_last_error_msg' ) ) :
/**
* Retrieves the error string of the last json_encode() or json_decode() call.
*
* @since 4.4.0
*
* @internal This is a compatibility function for PHP <5.5
*
* @return bool|string Returns the error message on success, "No Error" if no error has occurred,
* or false on failure.
*/
function json_last_error_msg() {
// See https://core.trac.wordpress.org/ticket/27799.
if ( ! function_exists( 'json_last_error' ) ) {
return false;
}
$last_error_code = json_last_error();
// Just in case JSON_ERROR_NONE is not defined.
$error_code_none = defined( 'JSON_ERROR_NONE' ) ? JSON_ERROR_NONE : 0;
switch ( true ) {
case $last_error_code === $error_code_none:
return 'No error';
case defined( 'JSON_ERROR_DEPTH' ) && JSON_ERROR_DEPTH === $last_error_code:
return 'Maximum stack depth exceeded';
case defined( 'JSON_ERROR_STATE_MISMATCH' ) && JSON_ERROR_STATE_MISMATCH === $last_error_code:
return 'State mismatch (invalid or malformed JSON)';
case defined( 'JSON_ERROR_CTRL_CHAR' ) && JSON_ERROR_CTRL_CHAR === $last_error_code:
return 'Control character error, possibly incorrectly encoded';
case defined( 'JSON_ERROR_SYNTAX' ) && JSON_ERROR_SYNTAX === $last_error_code:
return 'Syntax error';
case defined( 'JSON_ERROR_UTF8' ) && JSON_ERROR_UTF8 === $last_error_code:
return 'Malformed UTF-8 characters, possibly incorrectly encoded';
case defined( 'JSON_ERROR_RECURSION' ) && JSON_ERROR_RECURSION === $last_error_code:
return 'Recursion detected';
case defined( 'JSON_ERROR_INF_OR_NAN' ) && JSON_ERROR_INF_OR_NAN === $last_error_code:
return 'Inf and NaN cannot be JSON encoded';
case defined( 'JSON_ERROR_UNSUPPORTED_TYPE' ) && JSON_ERROR_UNSUPPORTED_TYPE === $last_error_code:
return 'Type is not supported';
default:
return 'An unknown error occurred';
}
}
endif;
if ( ! interface_exists( 'JsonSerializable' ) ) {
define( 'WP_JSON_SERIALIZE_COMPATIBLE', true );
/**
* JsonSerializable interface.
*
* Compatibility shim for PHP <5.4
*
* @link http://php.net/jsonserializable
*
* @since 4.4.0
*/
interface JsonSerializable {
public function jsonSerialize();
}
}
// random_int was introduced in PHP 7.0
if ( ! function_exists( 'random_int' ) ) {
require ABSPATH . WPINC . '/random_compat/random.php';
}