X-Git-Url: https://scripts.mit.edu/gitweb/autoinstalls/wordpress.git/blobdiff_plain/73db1360084ff9b194f8463cd9a45d4239546628..88550bc3400cc7c035ff590ecb007c7938041ded:/wp-includes/compat.php

diff --git a/wp-includes/compat.php b/wp-includes/compat.php
index cb2a5597..ab404525 100644
--- a/wp-includes/compat.php
+++ b/wp-includes/compat.php
@@ -94,3 +94,38 @@ if ( !function_exists('json_decode') ) {
 		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;
+
+// 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 );
+}