root/trunk/wp-includes/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.
 *
 * <code>
 * array (
 *        'rolename' => array (
 *            'name' => 'rolename',
 *            'capabilities' => array()
 *        )
 * )
 * </code>
 *
 * @since 2.0.0
 * @package WordPress
 * @subpackage User
 */
class WP_Roles {
    /**
     * List of roles and capabilities.
     *
     * @since 2.0.0
     * @access public
     * @var array
     */
    var $roles;

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

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

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

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

    /**
     * PHP4 Constructor - Call {@link WP_Roles::_init()} method.
     *
     * @since 2.0.0
     * @access public
     *
     * @return WP_Roles
     */
    function WP_Roles() {
        $this->_init();
    }

    /**
     * Setup 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
     * @uses $wpdb Used to get the database prefix.
     * @global array $wp_user_roles Used to set the 'roles' property value.
     */
    function _init () {
        global $wpdb;
        global $wp_user_roles;
        $this->role_key = $wpdb->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) $this->roles as $role => $data ) {
            $this->role_objects[$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.
     *
     * @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.
     * @return null|WP_Role WP_Role object if role is added, null if already exists.
     */
    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.
     */
    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 );
    }

    /**
     * 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 preforming capability.
     */
    function add_cap( $role, $cap, $grant = true ) {
        $this->roles[$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.
     */
    function remove_cap( $role, $cap ) {
        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 object|null Null, if role does not exist. WP_Role object, if found.
     */
    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.
     */
    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
     */
    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
     */
    var $name;

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

    /**
     * PHP4 Constructor - Setup 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 or not.
     *
     * @since 2.0.0
     * @access public
     *
     * @param string $role Role name.
     * @param array $capabilities List of capabilities.
     * @return WP_Role
     */
    function WP_Role( $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. 
     */
    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.
     */
    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.
     */
    function has_cap( $cap ) {
        $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
 */
class WP_User {
    /**
     * User data container.
     *
     * This will be set as properties of the object.
     *
     * @since 2.0.0
     * @access private
     * @var array
     */
    var $data;

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

    /**
     * The deprecated user's ID.
     *
     * @since 2.0.0
     * @access public
     * @deprecated Use WP_User::$ID
     * @see WP_User::$ID
     * @var int
     */
    var $id = 0;

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

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

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

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

    /**
     * First name of the user.
     *
     * Created to prevent notices.
     *
     * @since 2.7.0
     * @access public
     * @var string
     */
    var $first_name = '';

    /**
     * Last name of the user.
     *
     * Created to prevent notices.
     *
     * @since 2.7.0
     * @access public
     * @var string
     */
    var $last_name = '';

    /**
     * PHP4 Constructor - Sets up the object properties.
     *
     * Retrieves the userdata and then assigns all of the data keys to direct
     * properties of the object. Calls {@link WP_User::_init_caps()} after
     * setting up the object's user data properties.
     *
     * @since 2.0.0
     * @access public
     *
     * @param int|string $id User's ID or username
     * @param int $name Optional. User's username
     * @return WP_User
     */
    function WP_User( $id, $name = '' ) {

        if ( empty( $id ) && empty( $name ) )
            return;

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

        if ( ! empty( $id ) )
            $this->data = get_userdata( $id );
        else
            $this->data = get_userdatabylogin( $name );

        if ( empty( $this->data->ID ) )
            return;

        foreach ( get_object_vars( $this->data ) as $key => $value ) {
            $this->{$key} = $value;
        }

        $this->id = $this->ID;
        $this->_init_caps();
    }

    /**
     * Setup 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.
     *
     * @since 2.1.0
     * @access protected
     */
    function _init_caps() {
        global $wpdb;
        $this->cap_key = $wpdb->prefix . 'capabilities';
        $this->caps = &$this->{$this->cap_key};
        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
     */
    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 ) {
            $role = $wp_roles->get_role( $role );
            $this->allcaps = array_merge( $this->allcaps, $role->capabilities );
        }
        $this->allcaps = array_merge( $this->allcaps, $this->caps );
    }

    /**
     * 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.
     */
    function add_role( $role ) {
        $this->caps[$role] = true;
        update_usermeta( $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.
     */
    function remove_role( $role ) {
        if ( empty( $this->roles[$role] ) || ( count( $this->roles ) <= 1 ) )
            return;
        unset( $this->caps[$role] );
        update_usermeta( $this->ID, $this->cap_key, $this->caps );
        $this->get_role_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.
     */
    function set_role( $role ) {
        foreach ( (array) $this->roles as $oldrole )
            unset( $this->caps[$oldrole] );
        if ( !empty( $role ) ) {
            $this->caps[$role] = true;
            $this->roles = array( $role => true );
        } else {
            $this->roles = false;
        }
        update_usermeta( $this->ID, $this->cap_key, $this->caps );
        $this->get_role_caps();
        $this->update_user_level_from_caps();
    }

    /**
     * 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.
     */
    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
     */
    function update_user_level_from_caps() {
        global $wpdb;
        $this->user_level = array_reduce( array_keys( $this->allcaps ), array( &$this, 'level_reduction' ), 0 );
        update_usermeta( $this->ID, $wpdb->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.
     */
    function add_cap( $cap, $grant = true ) {
        $this->caps[$cap] = $grant;
        update_usermeta( $this->ID, $this->cap_key, $this->caps );
    }

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

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