diff options
Diffstat (limited to 'src/lib/net/port.go')
| -rw-r--r-- | src/lib/net/port.go | 32 |
1 files changed, 20 insertions, 12 deletions
diff --git a/src/lib/net/port.go b/src/lib/net/port.go index 528264ad6..cc7f39914 100644 --- a/src/lib/net/port.go +++ b/src/lib/net/port.go @@ -14,12 +14,17 @@ import ( "strconv"; ) +// The error returned by LookupPort when a network service +// is not listed in the database. +var ErrNoService = os.NewError("unknown network service"); + var services map[string] map[string] int +var servicesError *os.Error func readServices() { services = make(map[string] map[string] int); - // TODO(rsc): 6g won't let me do "file := " - var file = open("/etc/services"); + var file *file; + file, servicesError = open("/etc/services"); for line, ok := file.readLine(); ok; line, ok = file.readLine() { // "http 80/tcp www www-http # World Wide Web HTTP" if i := byteIndex(line, '#'); i >= 0 { @@ -49,21 +54,24 @@ func readServices() { file.close(); } -func LookupPort(netw, name string) (port int, ok bool) { +// LookupPort looks up the port for the given network and service. +func LookupPort(network, service string) (port int, err *os.Error) { once.Do(readServices); - switch netw { + switch network { case "tcp4", "tcp6": - netw = "tcp"; + network = "tcp"; case "udp4", "udp6": - netw = "udp"; + network = "udp"; } - m, mok := services[netw]; - if !mok { - return + m, ok := services[network]; + if !ok { + return 0, ErrNoService; + } + port, ok = m[service]; + if !ok { + return 0, ErrNoService; } - port, ok = m[name]; - return + return port, nil; } - |