/**
* Checks if the current user is a robot.
*
* @return bool
*/
private static function is_robot()
{
// Variant determiner for caches.
if (function_exists('vary_cache_on_function')) {
vary_cache_on_function('return isset( $_SERVER[\'HTTP_USER_AGENT\'] ) && preg_match( \'/bot|crawl|slurp|spider/i\', $_SERVER[\'HTTP_USER_AGENT\'] );');
}
return isset($_SERVER['HTTP_USER_AGENT']) && preg_match('/bot|crawl|slurp|spider/i', $_SERVER['HTTP_USER_AGENT']);
}
private static function is_specific_os($osUAs)
{
if (function_exists('vary_cache_on_function')) {
vary_cache_on_function('return (bool)preg_match("/(' . implode("|", $osUAs) . ')/i", $_SERVER["HTTP_USER_AGENT"]);');
}
return (bool) preg_match('/(' . implode('|', $osUAs) . ')/i', $_SERVER['HTTP_USER_AGENT']);
}
private static function run_vary_cache_on_function($test)
{
if (function_exists('vary_cache_on_function')) {
vary_cache_on_function($test);
}
$test_func = create_function('', $test);
return $test_func();
}
/**
* Generating function for batCache
*/
private function varyCache()
{
if (function_exists('vary_cache_on_function')) {
$cacheFunction = '
if ( preg_match( "/tinypass\\/callback/i", $_SERVER["HTTP_HOST"] ) ) {
return true;
}
$host = parse_url( $_SERVER["HTTP_HOST"] );
$host = isset( $host["host"] ) ? $host["host"] : false;
if ( $host ) {
$ref = false;
if ( ! empty( $_POST["_wp_http_referer"] ) ) {
$ref = wp_unslash( $_POST["_wp_http_referer"] );
} else if ( ! empty( $_GET["_wp_http_referer"] ) ) {
$ref = wp_unslash( $_GET["_wp_http_referer"] );
} else if ( ! empty( $_SERVER["HTTP_REFERER"] ) ) {
$ref = wp_unslash( $_SERVER["HTTP_REFERER"] );
}
if ( $ref && $ref !== wp_unslash( $_SERVER["REQUEST_URI"] ) ) {
$location = trim( $ref );
// browsers will assume http is your protocol, and will obey a redirect to a URL starting with //
if ( substr( $location, 0, 2 ) == "//" ) {
$location = "http:" . $location;
}
// In php 5 parse_url may fail if the URL query part contains http://, bug #38143
$test = ( $cut = strpos( $location, "?" ) ) ? substr( $location, 0, $cut ) : $location;
$lp = parse_url( $test );
// Give up if malformed URL
if ( false !== $lp ) {
// Allow only http and https schemes. No data:, etc.
if ( isset( $lp["scheme"] ) && ( "http" == $lp["scheme"] || "https" == $lp["scheme"] ) ) {
// Reject if scheme is set but host is not. This catches urls like https:host.com for which parse_url does not set the host field.
if ( isset( $lp["scheme"] ) && isset( $lp["host"] ) ) {
// if referred from outside
if ( ! preg_match( "/{$host}/", $location ) ) {
return true;
}
}
}
}
}
}
if ( array_key_exists( "__tac", $_COOKIE ) ) {
return $_COOKIE["__tac"];
}
return false;
';
vary_cache_on_function($cacheFunction);
}
}
/**
* Returns if the current visitor has a feed service user agent
*
* The function is batcache aware so that it does not serve matched user agents from cache.
*
* @author lloydbudd
* @return bool Returns true if the current visitor has a feed service user agent.
*/
function wpcom_vip_is_feedservice_ua()
{
if (function_exists('wpcom_feed_cache_headers')) {
// Workaround so that no feed request served from nginx wpcom-feed-cache
// If you are checking you must already know is a feed
// and don't want any requests cached
// ASSUMPTION: you've already confirmed is_feed() b/f calling
// wpcom_vip_is_feedservice_ua
header("X-Accel-Expires: 0");
}
if (function_exists('vary_cache_on_function')) {
// batcache variant
vary_cache_on_function('return (bool) preg_match("/feedburner|feedvalidator|MediafedMetrics/i", $_SERVER["HTTP_USER_AGENT"]);');
}
return (bool) preg_match("/feedburner|feedvalidator|MediafedMetrics/i", $_SERVER["HTTP_USER_AGENT"]);
}
/**
* run_vary_cache_func - environment-neutral interface to batcache's "vary_cache_on_function"
*
* Establishes whether or not to use a new cache variant by
* running an arbitrary function body provided via $test argument.
* $test is run both locally and in the batcache.
*
* @access private
* @param string [ $test ] function body used to determine user's
* eligibility. Must be a string in order to work with
* WP's batcache 'vary_cache_on_function' feature. Must
* include one or more references to "$_" variables.
* @return mixed (bool | string | int)
*/
private static function run_vary_cache_func($test)
{
if (preg_match('/include|require|echo|print|dump|export|open|sock|unlink|`|eval/i', $test)) {
trigger_error('Illegal word in cache variant function determiner.', E_USER_ERROR);
}
if (!preg_match('/\\$_/', $test)) {
trigger_error('Cache variant function should refer to at least one $_ variable.', E_USER_ERROR);
}
if (function_exists('vary_cache_on_function')) {
vary_cache_on_function($test);
}
$test_func = create_function('', $test);
return $test_func();
}
