Ticket #16956: capabilities.php

<?php
/**
 * WordPress Roles and Capabilities.
 *
 * @package WordPress
 * @subpackage User
 */

/**
 * WordPress User Roles.
 *
 * The role option is simple, the structure is organized by role name that store
 * the name in value of the 'name' key. The capabilities are stored as an array
 * in the value of the 'capability' key.
 *
 *     array (
 *              'rolename' => array (
 *                      'name' => 'rolename',
 *                      'capabilities' => array()
 *              )
 *     )
 *
 * @since 2.0.0
 * @package WordPress
 * @subpackage User
 */
class WP_Roles {
        /**
         * List of roles and capabilities.
         *
         * @since 2.0.0
         * @access public
         * @var array
         */
        public $roles;

        /**
         * List of the role objects.
         *
         * @since 2.0.0
         * @access public
         * @var array
         */
        public $role_objects = array();

        /**
         * List of role names.
         *
         * @since 2.0.0
         * @access public
         * @var array
         */
        public $role_names = array();

        /**
         * Option name for storing role list.
         *
         * @since 2.0.0
         * @access public
         * @var string
         */
        public $role_key;

        /**
         * Whether to use the database for retrieval and storage.
         *
         * @since 2.1.0
         * @access public
         * @var bool
         */
        public $use_db = true;

        /**
         * Constructor
         *
         * @since 2.0.0
         */
        public function __construct() {
                $this->_init();
        }

        /**
         * Make private/protected methods readable for backwards compatibility.
         *
         * @since 4.0.0
         * @access public
         *
         * @param callable $name      Method to call.
         * @param array    $arguments Arguments to pass when calling.
         * @return mixed|bool Return value of the callback, false otherwise.
         */
        public function __call( $name, $arguments ) {
                if ( '_init' === $name ) {
                        return call_user_func_array( array( $this, $name ), $arguments );
                }
                return false;
        }

        /**
         * Set up the object properties.
         *
         * The role key is set to the current prefix for the $wpdb object with
         * 'user_roles' appended. If the $wp_user_roles global is set, then it will
         * be used and the role option will not be updated or used.
         *
         * @since 2.1.0
         * @access protected
         *
         * @global wpdb  $wpdb          WordPress database abstraction object.
         * @global array $wp_user_roles Used to set the 'roles' property value.
         */
        protected function _init() {
                global $wpdb, $wp_user_roles;
                $this->role_key = $wpdb->get_blog_prefix() . 'user_roles';
                if ( ! empty( $wp_user_roles ) ) {
                        $this->roles = $wp_user_roles;
                        $this->use_db = false;
                } else {
                        $this->roles = get_option( $this->role_key );
                }

                if ( empty( $this->roles ) )
                        return;

                $this->role_objects = array();
                $this->role_names =  array();
                foreach ( array_keys( $this->roles ) as $role ) {
                        $this->role_objects[$role] = new WP_Role( $role, $this->roles[$role]['capabilities'] );
                        $this->role_names[$role] = $this->roles[$role]['name'];
                }
        }

        /**
         * Reinitialize the object
         *
         * Recreates the role objects. This is typically called only by switch_to_blog()
         * after switching wpdb to a new blog ID.
         *
         * @since 3.5.0
         * @access public
         */
        public function reinit() {
                // There is no need to reinit if using the wp_user_roles global.
                if ( ! $this->use_db )
                        return;

                global $wpdb;

                // Duplicated from _init() to avoid an extra function call.
                $this->role_key = $wpdb->get_blog_prefix() . 'user_roles';
                $this->roles = get_option( $this->role_key );
                if ( empty( $this->roles ) )
                        return;

                $this->role_objects = array();
                $this->role_names =  array();
                foreach ( array_keys( $this->roles ) as $role ) {
                        $this->role_objects[$role] = new WP_Role( $role, $this->roles[$role]['capabilities'] );
                        $this->role_names[$role] = $this->roles[$role]['name'];
                }
        }

        /**
         * Add role name with capabilities to list.
         *
         * Updates the list of roles, if the role doesn't already exist.
         *
         * The capabilities are defined in the following format `array( 'read' => true );`
         * To explicitly deny a role a capability you set the value for that capability to false.
         *
         * @since 2.0.0
         * @access public
         *
         * @param string $role Role name.
         * @param string $display_name Role display name.
         * @param array $capabilities List of role capabilities in the above format.
         * @return WP_Role|null WP_Role object if role is added, null if already exists.
         */
        public function add_role( $role, $display_name, $capabilities = array() ) {
                if ( isset( $this->roles[$role] ) )
                        return;

                $this->roles[$role] = array(
                        'name' => $display_name,
                        'capabilities' => $capabilities
                        );
                if ( $this->use_db )
                        update_option( $this->role_key, $this->roles );
                $this->role_objects[$role] = new WP_Role( $role, $capabilities );
                $this->role_names[$role] = $display_name;
                return $this->role_objects[$role];
        }

        /**
         * Remove role by name.
         *
         * @since 2.0.0
         * @access public
         *
         * @param string $role Role name.
         */
        public function remove_role( $role ) {
                if ( ! isset( $this->role_objects[$role] ) )
                        return;

                unset( $this->role_objects[$role] );
                unset( $this->role_names[$role] );
                unset( $this->roles[$role] );

                if ( $this->use_db )
                        update_option( $this->role_key, $this->roles );

                if ( get_option( 'default_role' ) == $role )
                        update_option( 'default_role', 'subscriber' );
        }

        /**
         * Add capability to role.
         *
         * @since 2.0.0
         * @access public
         *
         * @param string $role Role name.
         * @param string $cap Capability name.
         * @param bool $grant Optional, default is true. Whether role is capable of performing capability.
         */
        public function add_cap( $role, $cap, $grant = true ) {
                if ( ! isset( $this->roles[$role] ) )
                        return;

                $this->roles[$role]['capabilities'][$cap] = $grant;
                if ( $this->use_db )
                        update_option( $this->role_key, $this->roles );
        }

        /**
         * Remove capability from role.
         *
         * @since 2.0.0
         * @access public
         *
         * @param string $role Role name.
         * @param string $cap Capability name.
         */
        public function remove_cap( $role, $cap ) {
                if ( ! isset( $this->roles[$role] ) )
                        return;

                unset( $this->roles[$role]['capabilities'][$cap] );
                if ( $this->use_db )
                        update_option( $this->role_key, $this->roles );
        }

        /**
         * Retrieve role object by name.
         *
         * @since 2.0.0
         * @access public
         *
         * @param string $role Role name.
         * @return WP_Role|null WP_Role object if found, null if the role does not exist.
         */
        public function get_role( $role ) {
                if ( isset( $this->role_objects[$role] ) )
                        return $this->role_objects[$role];
                else
                        return null;
        }

        /**
         * Retrieve list of role names.
         *
         * @since 2.0.0
         * @access public
         *
         * @return array List of role names.
         */
        public function get_names() {
                return $this->role_names;
        }

        /**
         * Whether role name is currently in the list of available roles.
         *
         * @since 2.0.0
         * @access public
         *
         * @param string $role Role name to look up.
         * @return bool
         */
        public function is_role( $role ) {
                return isset( $this->role_names[$role] );
        }
}

/**
 * WordPress Role class.
 *
 * @since 2.0.0
 * @package WordPress
 * @subpackage User
 */
class WP_Role {
        /**
         * Role name.
         *
         * @since 2.0.0
         * @access public
         * @var string
         */
        public $name;

        /**
         * List of capabilities the role contains.
         *
         * @since 2.0.0
         * @access public
         * @var array
         */
        public $capabilities;

        /**
         * Constructor - Set up object properties.
         *
         * The list of capabilities, must have the key as the name of the capability
         * and the value a boolean of whether it is granted to the role.
         *
         * @since 2.0.0
         * @access public
         *
         * @param string $role Role name.
         * @param array $capabilities List of capabilities.
         */
        public function __construct( $role, $capabilities ) {
                $this->name = $role;
                $this->capabilities = $capabilities;
        }

        /**
         * Assign role a capability.
         *
         * @see WP_Roles::add_cap() Method uses implementation for role.
         * @since 2.0.0
         * @access public
         *
         * @param string $cap Capability name.
         * @param bool $grant Whether role has capability privilege.
         */
        public function add_cap( $cap, $grant = true ) {
                global $wp_roles;

                if ( ! isset( $wp_roles ) )
                        $wp_roles = new WP_Roles();

                $this->capabilities[$cap] = $grant;
                $wp_roles->add_cap( $this->name, $cap, $grant );
        }

        /**
         * Remove capability from role.
         *
         * This is a container for {@link WP_Roles::remove_cap()} to remove the
         * capability from the role. That is to say, that {@link
         * WP_Roles::remove_cap()} implements the functionality, but it also makes
         * sense to use this class, because you don't need to enter the role name.
         *
         * @since 2.0.0
         * @access public
         *
         * @param string $cap Capability name.
         */
        public function remove_cap( $cap ) {
                global $wp_roles;

                if ( ! isset( $wp_roles ) )
                        $wp_roles = new WP_Roles();

                unset( $this->capabilities[$cap] );
                $wp_roles->remove_cap( $this->name, $cap );
        }

        /**
         * Whether role has capability.
         *
         * The capabilities is passed through the 'role_has_cap' filter. The first
         * parameter for the hook is the list of capabilities the class has
         * assigned. The second parameter is the capability name to look for. The
         * third and final parameter for the hook is the role name.
         *
         * @since 2.0.0
         * @access public
         *
         * @param string $cap Capability name.
         * @return bool True, if user has capability. False, if doesn't have capability.
         */
        public function has_cap( $cap ) {
                /**
                 * Filter which capabilities a role has.
                 *
                 * @since 2.0.0
                 *
                 * @param array  $capabilities Array of role capabilities.
                 * @param string $cap          Capability name.
                 * @param string $name         Role name.
                 */
                $capabilities = apply_filters( 'role_has_cap', $this->capabilities, $cap, $this->name );
                if ( !empty( $capabilities[$cap] ) )
                        return $capabilities[$cap];
                else
                        return false;
        }

}

/**
 * WordPress User class.
 *
 * @since 2.0.0
 * @package WordPress
 * @subpackage User
 *
 * @property string $nickname
 * @property string $user_description
 * @property string $user_firstname
 * @property string $user_lastname
 * @property string $user_login
 * @property string $user_pass
 * @property string $user_nicename
 * @property string $user_email
 * @property string $user_url
 * @property string $user_registered
 * @property string $user_activation_key
 * @property string $user_status
 * @property string $display_name
 * @property string $spam
 * @property string $deleted
 */
class WP_User {
        /**
         * User data container.
         *
         * @since 2.0.0
         * @var object
         */
        public $data;

        /**
         * The user's ID.
         *
         * @since 2.1.0
         * @access public
         * @var int
         */
        public $ID = 0;

        /**
         * The individual capabilities the user has been given.
         *
         * @since 2.0.0
         * @access public
         * @var array
         */
        public $caps = array();

        /**
         * User metadata option name.
         *
         * @since 2.0.0
         * @access public
         * @var string
         */
        public $cap_key;

        /**
         * The roles the user is part of.
         *
         * @since 2.0.0
         * @access public
         * @var array
         */
        public $roles = array();

        /**
         * All capabilities the user has, including individual and role based.
         *
         * @since 2.0.0
         * @access public
         * @var array
         */
        public $allcaps = array();

        /**
         * The filter context applied to user data fields.
         *
         * @since 2.9.0
         * @access private
         * @var string
         */
        var $filter = null;

        private static $back_compat_keys;

        /**
         * Constructor
         *
         * Retrieves the userdata and passes it to {@link WP_User::init()}.
         *
         * @since 2.0.0
         * @access public
         *
         * @param int|string|stdClass|WP_User $id User's ID, a WP_User object, or a user object from the DB.
         * @param string $name Optional. User's username
         * @param int $blog_id Optional Blog ID, defaults to current blog.
         */
        public function __construct( $id = 0, $name = '', $blog_id = '' ) {
                if ( ! isset( self::$back_compat_keys ) ) {
                        $prefix = $GLOBALS['wpdb']->prefix;
                        self::$back_compat_keys = array(
                                'user_firstname' => 'first_name',
                                'user_lastname' => 'last_name',
                                'user_description' => 'description',
                                'user_level' => $prefix . 'user_level',
                                $prefix . 'usersettings' => $prefix . 'user-settings',
                                $prefix . 'usersettingstime' => $prefix . 'user-settings-time',
                        );
                }

                if ( $id instanceof WP_User ) {
                        $this->init( $id->data, $blog_id );
                        return;
                } elseif ( is_object( $id ) ) {
                        $this->init( $id, $blog_id );
                        return;
                }

                if ( ! empty( $id ) && ! is_numeric( $id ) ) {
                        $name = $id;
                        $id = 0;
                }

                if ( $id ) {
                        $data = self::get_data_by( 'id', $id );
                } else {
                        $data = self::get_data_by( 'login', $name );
                }

                if ( $data ) {
                        $this->init( $data, $blog_id );
                } else {
                        $this->data = new stdClass;
                }
        }

        /**
         * Sets up object properties, including capabilities.
         *
         * @param object $data User DB row object
         * @param int $blog_id Optional. The blog id to initialize for
         */
        public function init( $data, $blog_id = '' ) {
                $this->data = $data;
                $this->ID = (int) $data->ID;

                $this->for_blog( $blog_id );
        }

        /**
         * Return only the main user fields
         *
         * @since 3.3.0
         *
         * @param string $field The field to query against: 'id', 'slug', 'email' or 'login'
         * @param string|int $value The field value
         * @return object|false Raw user object
         */
        public static function get_data_by( $field, $value ) {
                global $wpdb;

                if ( 'id' == $field ) {
                        // Make sure the value is numeric to avoid casting objects, for example,
                        // to int 1.
                        if ( ! is_numeric( $value ) )
                                return false;
                        $value = intval( $value );
                        if ( $value < 1 )
                                return false;
                } else {
                        $value = trim( $value );
                }

                if ( !$value )
                        return false;

                switch ( $field ) {
                        case 'id':
                                $user_id = $value;
                                $db_field = 'ID';
                                break;
                        case 'slug':
                                $user_id = wp_cache_get($value, 'userslugs');
                                $db_field = 'user_nicename';
                                break;
                        case 'email':
                                $user_id = wp_cache_get($value, 'useremail');
                                $db_field = 'user_email';
                                break;
                        case 'login':
                                $value = sanitize_user( $value );
                                $user_id = wp_cache_get($value, 'userlogins');
                                $db_field = 'user_login';
                                break;
                        default:
                                return false;
                }

                if ( false !== $user_id ) {
                        if ( $user = wp_cache_get( $user_id, 'users' ) )
                                return $user;
                }

                if ( !$user = $wpdb->get_row( $wpdb->prepare(
                        "SELECT * FROM $wpdb->users WHERE $db_field = %s", $value
                ) ) )
                        return false;

                update_user_caches( $user );

                return $user;
        }

        /**
         * Magic method for checking the existence of a certain custom field
         *
         * @since 3.3.0
         * @param string $key
         * @return bool
         */
        public function __isset( $key ) {
                if ( 'id' == $key ) {
                        _deprecated_argument( 'WP_User->id', '2.1', __( 'Use <code>WP_User->ID</code> instead.' ) );
                        $key = 'ID';
                }

                if ( isset( $this->data->$key ) )
                        return true;

                if ( isset( self::$back_compat_keys[ $key ] ) )
                        $key = self::$back_compat_keys[ $key ];

                return metadata_exists( 'user', $this->ID, $key );
        }

        /**
         * Magic method for accessing custom fields
         *
         * @since 3.3.0
         * @param string $key
         * @return mixed
         */
        public function __get( $key ) {
                if ( 'id' == $key ) {
                        _deprecated_argument( 'WP_User->id', '2.1', __( 'Use <code>WP_User->ID</code> instead.' ) );
                        return $this->ID;
                }

                if ( isset( $this->data->$key ) ) {
                        $value = $this->data->$key;
                } else {
                        if ( isset( self::$back_compat_keys[ $key ] ) )
                                $key = self::$back_compat_keys[ $key ];
                        $value = get_user_meta( $this->ID, $key, true );
                }

                if ( $this->filter ) {
                        $value = sanitize_user_field( $key, $value, $this->ID, $this->filter );
                }

                return $value;
        }

        /**
         * Magic method for setting custom fields
         *
         * @since 3.3.0
         */
        public function __set( $key, $value ) {
                if ( 'id' == $key ) {
                        _deprecated_argument( 'WP_User->id', '2.1', __( 'Use <code>WP_User->ID</code> instead.' ) );
                        $this->ID = $value;
                        return;
                }

                $this->data->$key = $value;
        }

        /**
         * Determine whether the user exists in the database.
         *
         * @since 3.4.0
         * @access public
         *
         * @return bool True if user exists in the database, false if not.
         */
        public function exists() {
                return ! empty( $this->ID );
        }

        /**
         * Retrieve the value of a property or meta key.
         *
         * Retrieves from the users and usermeta table.
         *
         * @since 3.3.0
         *
         * @param string $key Property
         */
        public function get( $key ) {
                return $this->__get( $key );
        }

        /**
         * Determine whether a property or meta key is set
         *
         * Consults the users and usermeta tables.
         *
         * @since 3.3.0
         *
         * @param string $key Property
         */
        public function has_prop( $key ) {
                return $this->__isset( $key );
        }

        /**
         * Return an array representation.
         *
         * @since 3.5.0
         *
         * @return array Array representation.
         */
        public function to_array() {
                return get_object_vars( $this->data );
        }

        /**
         * Set up capability object properties.
         *
         * Will set the value for the 'cap_key' property to current database table
         * prefix, followed by 'capabilities'. Will then check to see if the
         * property matching the 'cap_key' exists and is an array. If so, it will be
         * used.
         *
         * @access protected
         * @since 2.1.0
         *
         * @param string $cap_key Optional capability key
         */
        function _init_caps( $cap_key = '' ) {
                global $wpdb;

                if ( empty($cap_key) )
                        $this->cap_key = $wpdb->get_blog_prefix() . 'capabilities';
                else
                        $this->cap_key = $cap_key;

                $this->caps = get_user_meta( $this->ID, $this->cap_key, true );

                if ( ! is_array( $this->caps ) )
                        $this->caps = array();

                $this->get_role_caps();
        }

        /**
         * Retrieve all of the role capabilities and merge with individual capabilities.
         *
         * All of the capabilities of the roles the user belongs to are merged with
         * the users individual roles. This also means that the user can be denied
         * specific roles that their role might have, but the specific user isn't
         * granted permission to.
         *
         * @since 2.0.0
         * @uses $wp_roles
         * @access public
         *
         * @return array List of all capabilities for the user.
         */
        public function get_role_caps() {
                global $wp_roles;

                if ( ! isset( $wp_roles ) )
                        $wp_roles = new WP_Roles();

                //Filter out caps that are not role names and assign to $this->roles
                if ( is_array( $this->caps ) )
                        $this->roles = array_filter( array_keys( $this->caps ), array( $wp_roles, 'is_role' ) );

                //Build $allcaps from role caps, overlay user's $caps
                $this->allcaps = array();
                foreach ( (array) $this->roles as $role ) {
                        $the_role = $wp_roles->get_role( $role );
                        $this->allcaps = array_merge( (array) $this->allcaps, (array) $the_role->capabilities );
                }
                $this->allcaps = array_merge( (array) $this->allcaps, (array) $this->caps );

                return $this->allcaps;
        }

        /**
         * Add role to user.
         *
         * Updates the user's meta data option with capabilities and roles.
         *
         * @since 2.0.0
         * @access public
         *
         * @param string $role Role name.
         */
        public function add_role( $role ) {
                $this->caps[$role] = true;
                update_user_meta( $this->ID, $this->cap_key, $this->caps );
                $this->get_role_caps();
                $this->update_user_level_from_caps();
        }

        /**
         * Remove role from user.
         *
         * @since 2.0.0
         * @access public
         *
         * @param string $role Role name.
         */
        public function remove_role( $role ) {
                if ( !in_array($role, $this->roles) )
                        return;
                unset( $this->caps[$role] );
                update_user_meta( $this->ID, $this->cap_key, $this->caps );
                $this->get_role_caps();
                $this->update_user_level_from_caps();
        }

        /**
         * Set the role of the user.
         *
         * This will remove the previous roles of the user and assign the user the
         * new one. You can set the role to an empty string and it will remove all
         * of the roles from the user.
         *
         * @since 2.0.0
         * @access public
         *
         * @param string $role Role name.
         */
        public function set_role( $role ) {
                if ( 1 == count( $this->roles ) && $role == current( $this->roles ) )
                        return;

                foreach ( (array) $this->roles as $oldrole )
                        unset( $this->caps[$oldrole] );

                $old_roles = $this->roles;
                if ( !empty( $role ) ) {
                        $this->caps[$role] = true;
                        $this->roles = array( $role => true );
                } else {
                        $this->roles = false;
                }
                update_user_meta( $this->ID, $this->cap_key, $this->caps );
                $this->get_role_caps();
                $this->update_user_level_from_caps();

                /**
                 * Fires after the user's role has changed.
                 *
                 * @since 2.9.0
                 * @since 3.6.0 Added $old_roles to include an array of the user's previous roles.
                 *
                 * @param int    $user_id   The user ID.
                 * @param string $role      The new role.
                 * @param array  $old_roles An array of the user's previous roles.
                 */
                do_action( 'set_user_role', $this->ID, $role, $old_roles );
        }

        /**
         * Choose the maximum level the user has.
         *
         * Will compare the level from the $item parameter against the $max
         * parameter. If the item is incorrect, then just the $max parameter value
         * will be returned.
         *
         * Used to get the max level based on the capabilities the user has. This
         * is also based on roles, so if the user is assigned the Administrator role
         * then the capability 'level_10' will exist and the user will get that
         * value.
         *
         * @since 2.0.0
         * @access public
         *
         * @param int $max Max level of user.
         * @param string $item Level capability name.
         * @return int Max Level.
         */
        public function level_reduction( $max, $item ) {
                if ( preg_match( '/^level_(10|[0-9])$/i', $item, $matches ) ) {
                        $level = intval( $matches[1] );
                        return max( $max, $level );
                } else {
                        return $max;
                }
        }

        /**
         * Update the maximum user level for the user.
         *
         * Updates the 'user_level' user metadata (includes prefix that is the
         * database table prefix) with the maximum user level. Gets the value from
         * the all of the capabilities that the user has.
         *
         * @since 2.0.0
         * @access public
         */
        public function update_user_level_from_caps() {
                global $wpdb;
                $this->user_level = array_reduce( array_keys( $this->allcaps ), array( $this, 'level_reduction' ), 0 );
                update_user_meta( $this->ID, $wpdb->get_blog_prefix() . 'user_level', $this->user_level );
        }

        /**
         * Add capability and grant or deny access to capability.
         *
         * @since 2.0.0
         * @access public
         *
         * @param string $cap Capability name.
         * @param bool $grant Whether to grant capability to user.
         */
        public function add_cap( $cap, $grant = true ) {
                $this->caps[$cap] = $grant;
                update_user_meta( $this->ID, $this->cap_key, $this->caps );
                $this->get_role_caps();
                $this->update_user_level_from_caps();
        }

        /**
         * Remove capability from user.
         *
         * @since 2.0.0
         * @access public
         *
         * @param string $cap Capability name.
         */
        public function remove_cap( $cap ) {
                if ( ! isset( $this->caps[ $cap ] ) ) {
                        return;
                }
                unset( $this->caps[ $cap ] );
                update_user_meta( $this->ID, $this->cap_key, $this->caps );
                $this->get_role_caps();
                $this->update_user_level_from_caps();
        }

        /**
         * Remove all of the capabilities of the user.
         *
         * @since 2.1.0
         * @access public
         */
        public function remove_all_caps() {
                global $wpdb;
                $this->caps = array();
                delete_user_meta( $this->ID, $this->cap_key );
                delete_user_meta( $this->ID, $wpdb->get_blog_prefix() . 'user_level' );
                $this->get_role_caps();
        }

        /**
         * Whether user has capability or role name.
         *
         * This is useful for looking up whether the user has a specific role
         * assigned to the user. The second optional parameter can also be used to
         * check for capabilities against a specific object, such as a post or user.
         *
         * @since 2.0.0
         * @access public
         *
         * @param string|int $cap Capability or role name to search.
         * @return bool True, if user has capability; false, if user does not have capability.
         */
        public function has_cap( $cap ) {
                if ( is_numeric( $cap ) ) {
                        _deprecated_argument( __FUNCTION__, '2.0', __('Usage of user levels by plugins and themes is deprecated. Use roles and capabilities instead.') );
                        $cap = $this->translate_level_to_cap( $cap );
                }

                $args = array_slice( func_get_args(), 1 );
                $args = array_merge( array( $cap, $this->ID ), $args );
                $caps = call_user_func_array( 'map_meta_cap', $args );

                // Multisite super admin has all caps by definition, Unless specifically denied.
                if ( is_multisite() && is_super_admin( $this->ID ) ) {
                        if ( in_array('do_not_allow', $caps) )
                                return false;
                        return true;
                }

                /**
                 * Dynamically filter a user's capabilities.
                 *
                 * @since 2.0.0
                 * @since 3.7.0 Added the user object.
                 *
                 * @param array   $allcaps An array of all the user's capabilities.
                 * @param array   $caps    Actual capabilities for meta capability.
                 * @param array   $args    Optional parameters passed to has_cap(), typically object ID.
                 * @param WP_User $user    The user object.
                 */
                // Must have ALL requested caps
                $capabilities = apply_filters( 'user_has_cap', $this->allcaps, $caps, $args, $this );
                $capabilities['exist'] = true; // Everyone is allowed to exist
                foreach ( (array) $caps as $cap ) {
                        if ( empty( $capabilities[ $cap ] ) )
                                return false;
                }

                return true;
        }

        /**
         * Convert numeric level to level capability name.
         *
         * Prepends 'level_' to level number.
         *
         * @since 2.0.0
         * @access public
         *
         * @param int $level Level number, 1 to 10.
         * @return string
         */
        public function translate_level_to_cap( $level ) {
                return 'level_' . $level;
        }

        /**
         * Set the blog to operate on. Defaults to the current blog.
         *
         * @since 3.0.0
         *
         * @param int $blog_id Optional Blog ID, defaults to current blog.
         */
        public function for_blog( $blog_id = '' ) {
                global $wpdb;
                if ( ! empty( $blog_id ) )
                        $cap_key = $wpdb->get_blog_prefix( $blog_id ) . 'capabilities';
                else
                        $cap_key = '';
                $this->_init_caps( $cap_key );
        }
}

/**
 * Map meta capabilities to primitive capabilities.
 *
 * This does not actually compare whether the user ID has the actual capability,
 * just what the capability or capabilities are. Meta capability list value can
 * be 'delete_user', 'edit_user', 'remove_user', 'promote_user', 'delete_post',
 * 'delete_page', 'edit_post', 'edit_page', 'read_post', or 'read_page'.
 *
 * @since 2.0.0
 *
 * @param string $cap Capability name.
 * @param int $user_id User ID.
 * @return array Actual capabilities for meta capability.
 */
function map_meta_cap( $cap, $user_id ) {
        $args = array_slice( func_get_args(), 2 );
        $caps = array();

        switch ( $cap ) {
        case 'remove_user':
                $caps[] = 'remove_users';
                break;
        case 'promote_user':
                $caps[] = 'promote_users';
                break;
        case 'edit_user':
        case 'edit_users':
                // Allow user to edit itself
                if ( 'edit_user' == $cap && isset( $args[0] ) && $user_id == $args[0] )
                        break;

                // If multisite these caps are allowed only for super admins.
                if ( is_multisite() && !is_super_admin( $user_id ) )
                        $caps[] = 'do_not_allow';
                else
                        $caps[] = 'edit_users'; // edit_user maps to edit_users.
                break;
        case 'delete_post':
        case 'delete_page':
                $post = get_post( $args[0] );

                if ( 'revision' == $post->post_type ) {
                        $post = get_post( $post->post_parent );
                }

                $post_type = get_post_type_object( $post->post_type );

                if ( post_type_exists($post->post_type) && ! $post_type->map_meta_cap ) {
                        $caps[] = $post_type->cap->$cap;
                        // Prior to 3.1 we would re-call map_meta_cap here.
                        if ( 'delete_post' == $cap )
                                $cap = $post_type->cap->$cap;
                        break;
                }

                // If the post author is set and the user is the author...
                if ( post_type_exists($post->post_type) ) {
                        if ( $post->post_author && $user_id == $post->post_author ) {
                                // If the post is published...
                                if ( 'publish' == $post->post_status ) {
                                        $caps[] = $post_type->cap->delete_published_posts;
                                } elseif ( 'trash' == $post->post_status ) {
                                        if ( 'publish' == get_post_meta( $post->ID, '_wp_trash_meta_status', true ) ) {
                                                $caps[] = $post_type->cap->delete_published_posts;
                                        }
                                } else {
                                        // If the post is draft...
                                        $caps[] = $post_type->cap->delete_posts;
                                }
                        } else {
                                // The user is trying to edit someone else's post.
                                $caps[] = $post_type->cap->delete_others_posts;
                                // The post is published, extra cap required.
                                if ( 'publish' == $post->post_status ) {
                                        $caps[] = $post_type->cap->delete_published_posts;
                                } elseif ( 'private' == $post->post_status ) {
                                        $caps[] = $post_type->cap->delete_private_posts;
                                }
                        }
                }
                break;
                // edit_post breaks down to edit_posts, edit_published_posts, or
                // edit_others_posts
        case 'edit_post':
        case 'edit_page':
                $post = get_post( $args[0] );
                if ( empty( $post ) )
                        break;

                if ( 'revision' == $post->post_type ) {
                        $post = get_post( $post->post_parent );
                }

                $post_type = get_post_type_object( $post->post_type );

                if ( post_type_exists($post->post_type) && ! $post_type->map_meta_cap ) {
                        $caps[] = $post_type->cap->$cap;
                        // Prior to 3.1 we would re-call map_meta_cap here.
                        if ( 'edit_post' == $cap )
                                $cap = $post_type->cap->$cap;
                        break;
                }

                // If the post author is set and the user is the author...
                if ( post_type_exists($post->post_type) ) {
                        if ( $post->post_author && $user_id == $post->post_author ) {
                                // If the post is published...
                                if ( 'publish' == $post->post_status ) {
                                        $caps[] = $post_type->cap->edit_published_posts;
                                } elseif ( 'trash' == $post->post_status ) {
                                        if ( 'publish' == get_post_meta( $post->ID, '_wp_trash_meta_status', true ) ) {
                                                $caps[] = $post_type->cap->edit_published_posts;
                                        }
                                } else {
                                        // If the post is draft...
                                        $caps[] = $post_type->cap->edit_posts;
                                }
                        } else {
                                // The user is trying to edit someone else's post.
                                $caps[] = $post_type->cap->edit_others_posts;
                                // The post is published, extra cap required.
                                if ( 'publish' == $post->post_status ) {
                                        $caps[] = $post_type->cap->edit_published_posts;
                                } elseif ( 'private' == $post->post_status ) {
                                        $caps[] = $post_type->cap->edit_private_posts;
                                }
                        }
                }
                break;
        case 'read_post':
        case 'read_page':
                $post = get_post( $args[0] );

                if ( 'revision' == $post->post_type ) {
                        $post = get_post( $post->post_parent );
                }

                $post_type = get_post_type_object( $post->post_type );

                if ( post_type_exists($post->post_type) && ! $post_type->map_meta_cap ) {
                        $caps[] = $post_type->cap->$cap;
                        // Prior to 3.1 we would re-call map_meta_cap here.
                        if ( 'read_post' == $cap )
                                $cap = $post_type->cap->$cap;
                        break;
                }

                $status_obj = get_post_status_object( $post->post_status );
                if ( post_type_exists($post->post_type) && $status_obj->public ) {
                        $caps[] = $post_type->cap->read;
                        break;
                }

                if ( post_type_exists($post->post_type) ) {
                        if ( $post->post_author && $user_id == $post->post_author ) {
                                $caps[] = $post_type->cap->read;
                        } elseif ( $status_obj->private ) {
                                $caps[] = $post_type->cap->read_private_posts;
                        } else {
                                $caps = map_meta_cap( 'edit_post', $user_id, $post->ID );
                        }
                }
                break;
        case 'publish_post':
                $post = get_post( $args[0] );
                $post_type = get_post_type_object( $post->post_type );

                if ( post_type_exists($post->post_type) ) {
                        $caps[] = $post_type->cap->publish_posts;
                }
                break;
        case 'edit_post_meta':
        case 'delete_post_meta':
        case 'add_post_meta':
                $post = get_post( $args[0] );
                $caps = map_meta_cap( 'edit_post', $user_id, $post->ID );

                $meta_key = isset( $args[ 1 ] ) ? $args[ 1 ] : false;

                if ( $meta_key && has_filter( "auth_post_meta_{$meta_key}" ) ) {
                        /**
                         * Filter whether the user is allowed to add post meta to a post.
                         *
                         * The dynamic portion of the hook name, `$meta_key`, refers to the
                         * meta key passed to {@see map_meta_cap()}.
                         *
                         * @since 3.3.0
                         *
                         * @param bool   $allowed  Whether the user can add the post meta. Default false.
                         * @param string $meta_key The meta key.
                         * @param int    $post_id  Post ID.
                         * @param int    $user_id  User ID.
                         * @param string $cap      Capability name.
                         * @param array  $caps     User capabilities.
                         */
                        $allowed = apply_filters( "auth_post_meta_{$meta_key}", false, $meta_key, $post->ID, $user_id, $cap, $caps );
                        if ( ! $allowed )
                                $caps[] = $cap;
                } elseif ( $meta_key && is_protected_meta( $meta_key, 'post' ) ) {
                        $caps[] = $cap;
                }
                break;
        case 'edit_comment':
                $comment = get_comment( $args[0] );
                if ( empty( $comment ) )
                        break;
                $post = get_post( $comment->comment_post_ID );
                $caps = map_meta_cap( 'edit_post', $user_id, $post->ID );
                break;
        case 'unfiltered_upload':
                if ( defined('ALLOW_UNFILTERED_UPLOADS') && ALLOW_UNFILTERED_UPLOADS && ( !is_multisite() || is_super_admin( $user_id ) )  )
                        $caps[] = $cap;
                else
                        $caps[] = 'do_not_allow';
                break;
        case 'unfiltered_html' :
                // Disallow unfiltered_html for all users, even admins and super admins.
                if ( defined( 'DISALLOW_UNFILTERED_HTML' ) && DISALLOW_UNFILTERED_HTML )
                        $caps[] = 'do_not_allow';
                elseif ( is_multisite() && ! is_super_admin( $user_id ) )
                        $caps[] = 'do_not_allow';
                else
                        $caps[] = $cap;
                break;
        case 'edit_files':
        case 'edit_plugins':
        case 'edit_themes':
                // Disallow the file editors.
                if ( defined( 'DISALLOW_FILE_EDIT' ) && DISALLOW_FILE_EDIT )
                        $caps[] = 'do_not_allow';
                elseif ( defined( 'DISALLOW_FILE_MODS' ) && DISALLOW_FILE_MODS )
                        $caps[] = 'do_not_allow';
                elseif ( is_multisite() && ! is_super_admin( $user_id ) )
                        $caps[] = 'do_not_allow';
                else
                        $caps[] = $cap;
                break;
        case 'update_plugins':
        case 'delete_plugins':
        case 'install_plugins':
        case 'upload_plugins':
        case 'update_themes':
        case 'delete_themes':
        case 'install_themes':
        case 'upload_themes':
        case 'update_core':
                // Disallow anything that creates, deletes, or updates core, plugin, or theme files.
                // Files in uploads are excepted.
                if ( defined( 'DISALLOW_FILE_MODS' ) && DISALLOW_FILE_MODS ) {
                        $caps[] = 'do_not_allow';
                } elseif ( is_multisite() && ! is_super_admin( $user_id ) ) {
                        $caps[] = 'do_not_allow';
                } elseif ( 'upload_themes' === $cap ) {
                        $caps[] = 'install_themes';
                } elseif ( 'upload_plugins' === $cap ) {
                        $caps[] = 'install_plugins';
                } else {
                        $caps[] = $cap;
                }
                break;
        case 'activate_plugins':
                $caps[] = $cap;
                if ( is_multisite() ) {
                        // update_, install_, and delete_ are handled above with is_super_admin().
                        $menu_perms = get_site_option( 'menu_items', array() );
                        if ( empty( $menu_perms['plugins'] ) )
                                $caps[] = 'manage_network_plugins';
                }
                break;
        case 'delete_user':
        case 'delete_users':
                // If multisite only super admins can delete users.
                if ( is_multisite() && ! is_super_admin( $user_id ) )
                        $caps[] = 'do_not_allow';
                else
                        $caps[] = 'delete_users'; // delete_user maps to delete_users.
                break;
        case 'create_users':
                if ( !is_multisite() )
                        $caps[] = $cap;
                elseif ( is_super_admin() || get_site_option( 'add_new_users' ) )
                        $caps[] = $cap;
                else
                        $caps[] = 'do_not_allow';
                break;
        case 'manage_links' :
                if ( get_option( 'link_manager_enabled' ) )
                        $caps[] = $cap;
                else
                        $caps[] = 'do_not_allow';
                break;
        case 'customize' :
                $caps[] = 'edit_theme_options';
                break;
        case 'delete_site':
                $caps[] = 'manage_options';
                break;
        default:
                // Handle meta capabilities for custom post types.
                $post_type_meta_caps = _post_type_meta_capabilities();
                if ( isset( $post_type_meta_caps[ $cap ] ) ) {
                        $args = array_merge( array( $post_type_meta_caps[ $cap ], $user_id ), $args );
                        return call_user_func_array( 'map_meta_cap', $args );
                }

                // If no meta caps match, return the original cap.
                $caps[] = $cap;
        }

        /**
         * Filter a user's capabilities depending on specific context and/or privilege.
         *
         * @since 2.8.0
         *
         * @param array  $caps    Returns the user's actual capabilities.
         * @param string $cap     Capability name.
         * @param int    $user_id The user ID.
         * @param array  $args    Adds the context to the cap. Typically the object ID.
         */
        return apply_filters( 'map_meta_cap', $caps, $cap, $user_id, $args );
}

/**
 * Whether current user has capability or role.
 *
 * @since 2.0.0
 *
 * @param string $capability Capability or role name.
 * @return bool
 */
function current_user_can( $capability ) {
        $current_user = wp_get_current_user();

        if ( empty( $current_user ) )
                return false;

        $args = array_slice( func_get_args(), 1 );
        $args = array_merge( array( $capability ), $args );

        return call_user_func_array( array( $current_user, 'has_cap' ), $args );
}

/**
 * Whether current user has a capability or role for a given blog.
 *
 * @since 3.0.0
 *
 * @param int $blog_id Blog ID
 * @param string $capability Capability or role name.
 * @return bool
 */
function current_user_can_for_blog( $blog_id, $capability ) {
        $switched = is_multisite() ? switch_to_blog( $blog_id ) : false;

        $current_user = wp_get_current_user();

        if ( empty( $current_user ) ) {
                if ( $switched ) {
                        restore_current_blog();
                }
                return false;
        }

        $args = array_slice( func_get_args(), 2 );
        $args = array_merge( array( $capability ), $args );

        $can = call_user_func_array( array( $current_user, 'has_cap' ), $args );

        if ( $switched ) {
                restore_current_blog();
        }

        return $can;
}

/**
 * Whether author of supplied post has capability or role.
 *
 * @since 2.9.0
 *
 * @param int|object $post Post ID or post object.
 * @param string $capability Capability or role name.
 * @return bool
 */
function author_can( $post, $capability ) {
        if ( !$post = get_post($post) )
                return false;

        $author = get_userdata( $post->post_author );

        if ( ! $author )
                return false;

        $args = array_slice( func_get_args(), 2 );
        $args = array_merge( array( $capability ), $args );

        return call_user_func_array( array( $author, 'has_cap' ), $args );
}

/**
 * Whether a particular user has capability or role.
 *
 * @since 3.1.0
 *
 * @param int|object $user User ID or object.
 * @param string $capability Capability or role name.
 * @return bool
 */
function user_can( $user, $capability ) {
        if ( ! is_object( $user ) )
                $user = get_userdata( $user );

        if ( ! $user || ! $user->exists() )
                return false;

        $args = array_slice( func_get_args(), 2 );
        $args = array_merge( array( $capability ), $args );

        return call_user_func_array( array( $user, 'has_cap' ), $args );
}

/**
 * Retrieve role object.
 *
 * @see WP_Roles::get_role() Uses method to retrieve role object.
 * @since 2.0.0
 *
 * @param string $role Role name.
 * @return WP_Role|null WP_Role object if found, null if the role does not exist.
 */
function get_role( $role ) {
        global $wp_roles;

        if ( ! isset( $wp_roles ) )
                $wp_roles = new WP_Roles();

        return $wp_roles->get_role( $role );
}

/**
 * Add role, if it does not exist.
 *
 * @see WP_Roles::add_role() Uses method to add role.
 * @since 2.0.0
 *
 * @param string $role Role name.
 * @param string $display_name Display name for role.
 * @param array $capabilities List of capabilities, e.g. array( 'edit_posts' => true, 'delete_posts' => false );
 * @return WP_Role|null WP_Role object if role is added, null if already exists.
 */
function add_role( $role, $display_name, $capabilities = array() ) {
        global $wp_roles;

        if ( ! isset( $wp_roles ) )
                $wp_roles = new WP_Roles();

        return $wp_roles->add_role( $role, $display_name, $capabilities );
}

/**
 * Remove role, if it exists.
 *
 * @see WP_Roles::remove_role() Uses method to remove role.
 * @since 2.0.0
 *
 * @param string $role Role name.
 */
function remove_role( $role ) {
        global $wp_roles;

        if ( ! isset( $wp_roles ) )
                $wp_roles = new WP_Roles();

        $wp_roles->remove_role( $role );
}

/**
 * Retrieve a list of super admins.
 *
 * @since 3.0.0
 *
 * @uses $super_admins Super admins global variable, if set.
 *
 * @return array List of super admin logins
 */
function get_super_admins() {
        global $super_admins;

        if ( isset($super_admins) )
                return $super_admins;
        else
                return get_site_option( 'site_admins', array('admin') );
}

/**
 * Determine if user is a site admin.
 *
 * @since 3.0.0
 *
 * @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 ) {
        if ( ! $user_id || $user_id == get_current_user_id() )
                $user = wp_get_current_user();
        else
                $user = get_userdata( $user_id );

        if ( ! $user || ! $user->exists() )
                return false;

        if ( is_multisite() ) {
                $super_admins = get_super_admins();
                if ( is_array( $super_admins ) && in_array( $user->user_login, $super_admins ) )
                        return true;
        } else {
                if ( $user->has_cap('delete_users') )
                        return true;
        }

        return false;
}