func extractHosts(hbs []byte) ([]string, int, error) {
var sl []string
pos, total := 0, 0
for i := 0; i < len(hbs); i++ {
if len(sl) > 0 && sl[len(sl)-1] == "0.0.0.0:0" {
logger.LogSteamInfo("0.0.0.0:0 detected. Got %d total hosts.", total-1)
break
}
if pos+6 > len(hbs) {
logger.LogSteamInfo("Got %d total hosts.", total)
break
}
host, err := parseIP(hbs[pos : pos+6])
if err != nil {
logger.LogAppErrorf("Error parsing host: %s", err)
} else {
sl = append(sl, host)
total++
}
// host:port = 6 bytes
pos = pos + 6
}
return sl, total, nil
}
// NewMasterWebQuery initiates a new Steam "Master" server query using the Steam Web API for a
// given filter, returning a MasterQuery struct containing the hosts retrieved in the event of
// success or an empty struct and an error in the event of failure.
func NewMasterWebQuery(filter filters.Filter) (MasterQuery, error) {
sl, err := getServersWeb(filter)
if err != nil {
return MasterQuery{}, err
}
logger.LogSteamInfo("*** Retrieved %d %s servers.", len(sl), filter.Game.Name)
return MasterQuery{Servers: sl}, nil
}
func getServers(filter filters.Filter) ([]string, error) {
maxHosts := config.Config.SteamConfig.MaximumHostsToReceive
var serverlist []string
var c net.Conn
var err error
retrieved := 0
addr := "0.0.0.0:0"
c, err = net.DialTimeout("udp", masterServerHost,
time.Duration(QueryTimeout)*time.Second)
if err != nil {
logger.LogSteamError(ErrHostConnection(err.Error()))
return nil, ErrHostConnection(err.Error())
}
defer c.Close()
c.SetDeadline(time.Now().Add(time.Duration(QueryTimeout) * time.Second))
for {
s, err := queryMasterServer(c, addr, filter)
if err != nil {
// usually timeout - Valve throttles >30 UDP packets (>6930 servers) per min
logger.WriteDebug("Master query error, likely due to Valve throttle/timeout :%s",
err)
break
}
// get hosts:ports beginning after header (0xFF, 0xFF, 0xFF, 0xFF, 0x66, 0x0A)
ips, total, err := extractHosts(s[6:])
if err != nil {
return nil, logger.LogAppErrorf("Error when extracting addresses: %s",
err)
}
retrieved = retrieved + total
if retrieved >= maxHosts {
logger.LogSteamInfo("Max host limit of %d reached!", maxHosts)
logger.WriteDebug("Max host limit of %d reached!", maxHosts)
break
}
logger.LogSteamInfo("%d hosts retrieved so far from master.", retrieved)
logger.WriteDebug("%d hosts retrieved so far from master.", retrieved)
for _, ip := range ips {
serverlist = append(serverlist, ip)
}
if (serverlist[len(serverlist)-1]) != "0.0.0.0:0" {
logger.LogSteamInfo("More hosts need to be retrieved. Last IP was: %s",
serverlist[len(serverlist)-1])
logger.WriteDebug("More hosts need to be retrieved. Last IP was: %s",
serverlist[len(serverlist)-1])
addr = serverlist[len(serverlist)-1]
} else {
logger.LogSteamInfo("IP retrieval complete!")
logger.WriteDebug("IP retrieval complete!")
break
}
}
// remove 0.0.0.0:0
if len(serverlist) != 0 {
if serverlist[len(serverlist)-1] == "0.0.0.0:0" {
serverlist = serverlist[:len(serverlist)-1]
}
}
return serverlist, nil
}