From 8a5d80111727450728ade26b29dc4f6438784483 Mon Sep 17 00:00:00 2001
From: Ryan Boren <ryan@git.wordpress.org>
Date: Wed, 6 Jan 2010 23:27:22 +0000
Subject: [PATCH] Introduce is_super_admin(). see #11644.

git-svn-id: https://develop.svn.wordpress.org/trunk@12611 602fd350-edb4-49c9-b593-d223f7449a82
---
 wp-includes/capabilities.php | 29 +++++++++++++++++++++++++++++
 wp-includes/ms-functions.php | 33 ++++++++++++++++++---------------
 2 files changed, 47 insertions(+), 15 deletions(-)

diff --git a/wp-includes/capabilities.php b/wp-includes/capabilities.php
index ca6fedad34..01d4b61a2a 100644
--- a/wp-includes/capabilities.php
+++ b/wp-includes/capabilities.php
@@ -1062,4 +1062,33 @@ function remove_role( $role ) {
 	return $wp_roles->remove_role( $role );
 }
 
+/**
+ * Determine if user is a site admin.
+ *
+ * @since 3.0
+ *
+ * @param int $user_id (Optional) The ID of a user. Defaults to the current user.
+ * @return bool True if the user is a site admin.
+ */
+function is_super_admin( $user_id = false ) {
+	global $current_user;
+
+	if ( !$current_user && !$user_id )
+		return false;
+
+	if ( !$user_id )
+		$user_id = $current_user->id;
+
+	if ( !$user_id )
+		return false;
+
+	$user = new WP_User($user_id);
+
+	$site_admins = get_site_option( 'site_admins', array('admin') );
+	if ( is_array( $site_admins ) && in_array( $user->user_login, $site_admins ) )
+		return true;
+
+	return false;
+}
+
 ?>
diff --git a/wp-includes/ms-functions.php b/wp-includes/ms-functions.php
index 4c8e19e156..f4560f2190 100644
--- a/wp-includes/ms-functions.php
+++ b/wp-includes/ms-functions.php
@@ -183,25 +183,28 @@ function get_current_user_id() {
 	return $current_user->ID;
 }
 
-function is_site_admin( $user_login = false ) {
-	global $current_user;
+/**
+ * Determine if user is a site admin.
+ *
+ * @deprecated Use {@link is_keymaster()}
+ * 
+ */
+function is_site_admin( $user_login = '' ) {
+	// This function must reside in a file included only if is_multsite() since many plugins
+	// test for its existence to determine if multisite is enabled.
 
-	if ( !$current_user && !$user_login )
-		return false;
-
-	if ( $user_login ) {
-		$user_login = sanitize_user( $user_login );
-	} elseif( isset( $current_user->user_login ) ) {
-		$user_login = $current_user->user_login;
+	if ( empty($user_login) ) {
+		$user_id = get_current_user_id();
+		if ( !$user_id )
+			return false;
 	} else {
-		return false;
+		$user = new WP_User(null, $user_login);
+		if ( empty($user->id) )
+			return false;
+		$user_id = $user->id;
 	}
 
-	$site_admins = get_site_option( 'site_admins', array('admin') );
-	if( is_array( $site_admins ) && in_array( $user_login, $site_admins ) )
-		return true;
-
-	return false;
+	return is_super_admin($user_id);
 }
 
 /**