root/trunk/wp-includes/wpmu-functions.php

<?php
/*
    Helper functions for WPMU
*/
function load_muplugin_textdomain($domain, $path = false) {
    $locale = get_locale();
    if ( empty($locale) )
        $locale = 'en_US';

    if ( false === $path )
        $path = WPMU_PLUGIN_DIR;

    $mofile = WPMU_PLUGIN_DIR . "/$domain-$locale.mo";
    load_textdomain($domain, $mofile);
}

function wpmu_update_blogs_date() {
    global $wpdb;

    $wpdb->update( $wpdb->blogs, array('last_updated' => current_time('mysql')), array('blog_id' => $wpdb->blogid) );
    refresh_blog_details( $wpdb->blogid );

    do_action( 'wpmu_blog_updated', $wpdb->blogid );
}

function get_blogaddress_by_id( $blog_id ) {
    $bloginfo = get_blog_details( (int) $blog_id, false ); // only get bare details!
    return clean_url("http://" . $bloginfo->domain . $bloginfo->path);
}

function get_blogaddress_by_name( $blogname ) {
    global $hostname, $domain, $base;

    if( defined( "VHOST" ) && constant( "VHOST" ) == 'yes' ) {
        if( $blogname == 'main' )
            $blogname = 'www';
        return clean_url("http://".$blogname.".".$domain.$base);
    } else {
        return clean_url("http://".$hostname.$base.$blogname);
    }
}

function get_blogaddress_by_domain( $domain, $path ){
    if( defined( "VHOST" ) && constant( "VHOST" ) == 'yes' ) {
        $url = "http://".$domain.$path;
    } else {
        if( $domain != $_SERVER['HTTP_HOST'] ) {
            $blogname = substr( $domain, 0, strpos( $domain, '.' ) );
            if( $blogname != 'www.' ) {
                $url = 'http://' . substr( $domain, strpos( $domain, '.' ) + 1 ) . $path . $blogname . '/';
            } else { // we're installing the main blog
                $url = 'http://' . substr( $domain, strpos( $domain, '.' ) + 1 ) . $path;
            }
        } else { // main blog
            $url = 'http://' . $domain . $path;
        }
    }
    return clean_url($url);
}

function get_sitestats() {
    global $wpdb;

    $stats['blogs'] = get_blog_count();

    $count_ts = get_site_option( "get_user_count_ts" );
    if( time() - $count_ts > 3600 ) {
        $count = $wpdb->get_var( "SELECT COUNT(ID) FROM {$wpdb->users}" );
        update_site_option( "user_count", $count );
        update_site_option( "user_count_ts", time() );
    } else {
        $count = get_site_option( "user_count" );
    }
    $stats['users'] = $count;
    return $stats;
}

function get_admin_users_for_domain( $sitedomain = '', $path = '' ) {
    global $wpdb;
    
    if( $sitedomain == '' ) {
        $site_id = $wpdb->siteid;
    } else {
        $site_id = $wpdb->get_var( $wpdb->prepare("SELECT id FROM $wpdb->site WHERE domain = %s AND path = %s", $sitedomain, $path) );
    }
    
    if( $site_id != false ) {
        return $wpdb->get_results( $wpdb->prepare("SELECT u.ID, u.user_login, u.user_pass FROM $wpdb->users AS u, $wpdb->sitemeta AS sm WHERE sm.meta_key = 'admin_user_id' AND u.ID = %d AND sm.site_id = %d", $wpdb->sitemeta.'.meta_value', $site_id), ARRAY_A );
    }
    return false;
}

function get_user_details( $username ) {
    global $wpdb;
    return $wpdb->get_row( $wpdb->prepare("SELECT * FROM $wpdb->users WHERE user_login = %s", $username) );
}

function is_main_blog() {
    global $current_blog, $current_site;
    if( $current_blog->domain == $current_site->domain && $current_blog->path == $current_site->path )
        return true;
    return false;
}

function get_id_from_blogname( $name ) {
    global $wpdb, $current_site;
    if( constant( 'VHOST' ) == 'yes' ) {
        $domain = $name . '.' . $current_site->domain;
        $path = $current_site->path;
    } else {
        $domain = $current_site->domain;
        $path = $current_site->path . $name;
    }
    return $wpdb->get_var( $wpdb->prepare("SELECT blog_id FROM {$wpdb->blogs} WHERE domain = %s AND path = %s", $domain, $path) );
}

function get_blog_details( $id, $getall = true ) {
    global $wpdb;

    if( !is_numeric( $id ) ) {
        $id = get_id_from_blogname( $id );
    }
    $all = $getall == true ? '' : 'short';
    $details = wp_cache_get( $id . $all, 'blog-details' );

    if ( $details ) {
        if ( $details == -1 )
            return false;
        elseif ( !is_object($details) ) // Clear old pre-serialized objects. Cache clients do better with that.
            wp_cache_delete( $id . $all, 'blog-details' );
        else
            return $details;
    }

    $details = $wpdb->get_row( $wpdb->prepare("SELECT * FROM $wpdb->blogs WHERE blog_id = %d", $id) ); // get_blog_details ?
    if ( !$details ) {
        wp_cache_set( $id . $all, -1, 'blog-details' );
        return false;
    }

    if ( !$getall ) {
        wp_cache_add( $id . $all, $details, 'blog-details' );
        return $details;
    }

    $wpdb->suppress_errors();
    $details->blogname   = get_blog_option($id, 'blogname');
    $details->siteurl    = get_blog_option($id, 'siteurl');
    $details->post_count = get_blog_option($id, 'post_count');
    $wpdb->suppress_errors( false );

    $details = apply_filters('blog_details', $details);

    wp_cache_set( $id . $all, $details, 'blog-details' );

    $key = md5( $details->domain . $details->path );
    wp_cache_set( $key, $details, 'blog-lookup' );

    return $details;
}

function refresh_blog_details( $id ) {
    $id = (int) $id;
    $details = get_blog_details( $id, false );
    
    wp_cache_delete( $id , 'blog-details' );
    wp_cache_delete( md5( $details->domain . $details->path )  , 'blog-lookup' );
}

function get_current_user_id() {
    global $current_user;
    return $current_user->ID;
}

function is_site_admin( $user_login = false ) {
    global $current_user;

    if ( !$current_user && !$user_login )
        return false;

    if ( $user_login )
        $user_login = sanitize_user( $user_login );
    else
        $user_login = $current_user->user_login;

    $site_admins = get_site_option( 'site_admins', array('admin') );
    if( is_array( $site_admins ) && in_array( $user_login, $site_admins ) )
        return true;

    return false;
}

// expects key not to be SQL escaped
function get_site_option( $key, $default = false, $use_cache = true ) {
    global $wpdb;

    // Allow plugins to short-circuit site options. 
     $pre = apply_filters( 'pre_site_option_' . $key, false ); 
     if ( false !== $pre ) 
         return $pre; 

    if( $use_cache == true ) {
        $value = wp_cache_get($wpdb->siteid . $key, 'site-options');
    } else {
        $value = false;
    }

    if ( false === $value ) {
        $value = $wpdb->get_var( $wpdb->prepare("SELECT meta_value FROM $wpdb->sitemeta WHERE meta_key = %s AND site_id = %d", $key, $wpdb->siteid) );
        if ( ! is_null($value) ) {
            wp_cache_add($wpdb->siteid . $key, $value, 'site-options');
        } elseif ( $default ) {
            wp_cache_add($wpdb->siteid . $key, addslashes( $default ), 'site-options');
            return $default;
        } else {
            wp_cache_add($wpdb->siteid . $key, false, 'site-options');
            return false;
        }
    }

    if (! unserialize($value) ) 
        $value = stripslashes( $value ); 

    return apply_filters( 'site_option_' . $key, maybe_unserialize( $value ) );
}

// expects $key, $value not to be SQL escaped
function add_site_option( $key, $value ) {
    global $wpdb;

    $exists = $wpdb->get_row( $wpdb->prepare("SELECT meta_value FROM $wpdb->sitemeta WHERE meta_key = %s AND site_id = %d", $key, $wpdb->siteid) );
    if ( is_object( $exists ) ) {// If we already have it
        update_site_option( $key, $value );
        return false;
    }

    if ( is_array($value) || is_object($value) )
        $value = serialize($value);
    wp_cache_delete($wpdb->siteid . $key, 'site-options');

    $wpdb->insert( $wpdb->sitemeta, array('site_id' => $wpdb->siteid, 'meta_key' => $key, 'meta_value' => $value) );
    return $wpdb->insert_id; 
}

// expects $key, $value not to be SQL escaped
function update_site_option( $key, $value ) {
    global $wpdb;

    if ( $value == get_site_option( $key ) )
         return false;

    $exists = $wpdb->get_row( $wpdb->prepare("SELECT meta_value FROM $wpdb->sitemeta WHERE meta_key = %s AND site_id = %d", $key, $wpdb->siteid) );
    if ( false == is_object( $exists ) ) // It's a new record
        return add_site_option( $key, $value );

    if ( is_array($value) || is_object($value) )
        $value = serialize($value);

    $wpdb->update( $wpdb->sitemeta, array('meta_value' => $value), array('site_id' => $wpdb->siteid, 'meta_key' => $key) );
    wp_cache_delete( $wpdb->siteid . $key, 'site-options' );
    return true;
}

/*
function get_blog_option( $id, $key, $default='na' ) {
    switch_to_blog($id);
    $option = get_option( $key );
    restore_current_blog();
    return $option;
}
*/

function get_blog_option( $blog_id, $setting, $deprecated = '' ) {
    global $wpdb;

    $key = $blog_id."-".$setting."-blog_option";
    $value = wp_cache_get( $key, "site-options" );
    if( $value == null ) {
        $row = $wpdb->get_row( $wpdb->prepare("SELECT * FROM {$wpdb->base_prefix}{$blog_id}_options WHERE option_name = %s", $setting) );
        if( is_object( $row) ) { // Has to be get_row instead of get_var because of funkiness with 0, false, null values
            $value = $row->option_value;
            if( $value == false ) {
                wp_cache_set($key, 'falsevalue', 'site-options');
                return false;
            } else {
                wp_cache_set($key, $value, 'site-options');
            }
        } else { // option does not exist, so we must cache its non-existence
            wp_cache_set($key, 'noop', 'site-options');
        }
    } elseif( $value == 'noop' ) {
        return false;
    } elseif( $value == 'falsevalue' ) {
        return false;
    }
    // If home is not set use siteurl.
    if ( 'home' == $setting && '' == $value )
        return get_blog_option($blog_id, 'siteurl');

    if ( 'siteurl' == $setting || 'home' == $setting || 'category_base' == $setting )
        $value = preg_replace('|/+$|', '', $value);

    if (! unserialize($value) )
        $value = stripslashes( $value );

    return apply_filters( 'option_' . $setting, maybe_unserialize($value) );
}

function add_blog_option( $id, $key, $value ) {
    $id = (int) $id;
    
    switch_to_blog($id);
    add_option( $key, $value );
    restore_current_blog();
    wp_cache_set( $id."-".$key."-blog_option", $value, 'site-options' );
}

function delete_blog_option( $id, $key ) {
    $id = (int) $id;
    
    switch_to_blog($id);
    delete_option( $key );
    restore_current_blog();
    wp_cache_set( $id."-".$key."-blog_option", '', 'site-options' );
}

function update_blog_option( $id, $key, $value, $refresh = true ) {
    $id = (int) $id;
    
    switch_to_blog($id);
    update_option( $key, $value );
    restore_current_blog();
    
    if( $refresh == true ) {
        refresh_blog_details( $id );
    }
    wp_cache_set( $id."-".$key."-blog_option", $value, 'site-options');
}

function switch_to_blog( $new_blog ) {
    global $wpdb, $table_prefix, $blog_id, $switched, $switched_stack, $wp_roles, $current_user, $wp_object_cache;

    if ( empty($new_blog) )
        return false;

    if ( empty($switched_stack) )
        $switched_stack = array();

    $switched_stack[] = $blog_id;

    if ( $blog_id == $new_blog )
        return false;

    $wp_object_cache->switched_cache[ $blog_id ] = $wp_object_cache->cache;
    unset( $wp_object_cache->cache );

    $wpdb->set_blog_id($new_blog);
    $table_prefix = $wpdb->prefix;
    $prev_blog_id = $blog_id;
    $blog_id = $new_blog;

    if( is_object( $wp_roles ) ) {
        $wpdb->suppress_errors();
        $wp_roles->_init();
        $wpdb->suppress_errors( false );
    }

    if ( is_object( $current_user ) )
        $current_user->_init_caps();

    do_action('switch_blog', $blog_id, $prev_blog_id);
    $switched = true;
    return true;
}

function restore_current_blog() {
    global $table_prefix, $wpdb, $blog_id, $switched, $switched_stack, $wp_roles, $current_user, $wp_object_cache;

    if ( !$switched )
        return false;

    $blog = array_pop($switched_stack);
    if ( $blog_id == $blog )
        return false;

    $wp_object_cache->cache = $wp_object_cache->switched_cache[ $blog ];
    unset( $wp_object_cache->switched_cache[ $blog ] );

    $wpdb->set_blog_id($blog);
    $prev_blog_id = $blog_id;
    $blog_id = $blog;
    $table_prefix = $wpdb->prefix;

    if( is_object( $wp_roles ) ) {
        $wpdb->suppress_errors();
        $wp_roles->_init();
        $wpdb->suppress_errors( false );
    }

    if ( is_object( $current_user ) )
        $current_user->_init_caps();

    do_action('switch_blog', $blog_id, $prev_blog_id);

    $switched = false;
    return true;
}

function get_blogs_of_user( $id, $all = false ) {
    global $wpdb;

    $user = get_userdata( (int) $id );
    if ( !$user )
        return false;

    $blogs = $match = array();
    foreach ( (array) $user as $key => $value ) {
        if ( strstr( $key, '_capabilities') && strstr( $key, $wpdb->base_prefix) ) {
            preg_match('/' . $wpdb->base_prefix . '(\d+)_capabilities/', $key, $match);
            $blog = get_blog_details( $match[1] );
            if ( $blog && isset( $blog->domain ) && ( $all == true || $all == false && ( $blog->archived == 0 && $blog->spam == 0 && $blog->deleted == 0 ) ) ) {
                $blogs[$match[1]]->userblog_id = $match[1];
                $blogs[$match[1]]->blogname    = $blog->blogname;
                $blogs[$match[1]]->domain      = $blog->domain;
                $blogs[$match[1]]->path        = $blog->path;
                $blogs[$match[1]]->site_id     = $blog->site_id;
                $blogs[$match[1]]->siteurl     = $blog->siteurl;
            }
        }
    }

    return $blogs;
}

function get_active_blog_for_user( $user_id ) { // get an active blog for user - either primary blog or from blogs list
    $primary_blog = get_usermeta( $user_id, "primary_blog" );
    if( $primary_blog == false ) {
        $details = false;
    } else {
        $details = get_blog_details( $primary_blog );
    }

    if( ( is_object( $details ) == false ) || ( is_object( $details ) && $details->archived == 1 || $details->spam == 1 || $details->deleted == 1 ) ) {
        $blogs = get_blogs_of_user( $user_id, true ); // if a user's primary blog is shut down, check their other blogs.
        $ret = false;
        if( is_array( $blogs ) && count( $blogs ) > 0 ) {
            foreach( (array) $blogs as $blog_id => $blog ) {
                $details = get_blog_details( $blog_id );
                if( is_object( $details ) && $details->archived == 0 && $details->spam == 0 && $details->deleted == 0 ) {
                    $ret = $blog;
                    break;
                }
            }
        } else {
            $ret = "username only"; // user has no blogs. We can add details for dashboard.wordpress.com here.
        }
        return $ret;
    } else {