Retro68/gcc/libgo/go/net/ipsock_plan9.go
2015-08-28 17:33:40 +02:00

229 lines
5.1 KiB
Go

// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Internet protocol family sockets for Plan 9
package net
import (
"errors"
"os"
"syscall"
)
func probe(filename, query string) bool {
var file *file
var err error
if file, err = open(filename); err != nil {
return false
}
r := false
for line, ok := file.readLine(); ok && !r; line, ok = file.readLine() {
f := getFields(line)
if len(f) < 3 {
continue
}
for i := 0; i < len(f); i++ {
if query == f[i] {
r = true
break
}
}
}
file.close()
return r
}
func probeIPv4Stack() bool {
return probe(netdir+"/iproute", "4i")
}
// probeIPv6Stack returns two boolean values. If the first boolean
// value is true, kernel supports basic IPv6 functionality. If the
// second boolean value is true, kernel supports IPv6 IPv4-mapping.
func probeIPv6Stack() (supportsIPv6, supportsIPv4map bool) {
// Plan 9 uses IPv6 natively, see ip(3).
r := probe(netdir+"/iproute", "6i")
v := false
if r {
v = probe(netdir+"/iproute", "4i")
}
return r, v
}
// parsePlan9Addr parses address of the form [ip!]port (e.g. 127.0.0.1!80).
func parsePlan9Addr(s string) (ip IP, iport int, err error) {
addr := IPv4zero // address contains port only
i := byteIndex(s, '!')
if i >= 0 {
addr = ParseIP(s[:i])
if addr == nil {
return nil, 0, errors.New("parsing IP failed")
}
}
p, _, ok := dtoi(s[i+1:], 0)
if !ok {
return nil, 0, errors.New("parsing port failed")
}
if p < 0 || p > 0xFFFF {
return nil, 0, &AddrError{"invalid port", string(p)}
}
return addr, p, nil
}
func readPlan9Addr(proto, filename string) (addr Addr, err error) {
var buf [128]byte
f, err := os.Open(filename)
if err != nil {
return
}
defer f.Close()
n, err := f.Read(buf[:])
if err != nil {
return
}
ip, port, err := parsePlan9Addr(string(buf[:n]))
if err != nil {
return
}
switch proto {
case "tcp":
addr = &TCPAddr{IP: ip, Port: port}
case "udp":
addr = &UDPAddr{IP: ip, Port: port}
default:
return nil, errors.New("unknown protocol " + proto)
}
return addr, nil
}
func startPlan9(net string, addr Addr) (ctl *os.File, dest, proto, name string, err error) {
var (
ip IP
port int
)
switch a := addr.(type) {
case *TCPAddr:
proto = "tcp"
ip = a.IP
port = a.Port
case *UDPAddr:
proto = "udp"
ip = a.IP
port = a.Port
default:
err = UnknownNetworkError(net)
return
}
clone, dest, err := queryCS1(proto, ip, port)
if err != nil {
return
}
f, err := os.OpenFile(clone, os.O_RDWR, 0)
if err != nil {
return
}
var buf [16]byte
n, err := f.Read(buf[:])
if err != nil {
f.Close()
return
}
return f, dest, proto, string(buf[:n]), nil
}
func netErr(e error) {
oe, ok := e.(*OpError)
if !ok {
return
}
if pe, ok := oe.Err.(*os.PathError); ok {
if _, ok = pe.Err.(syscall.ErrorString); ok {
oe.Err = pe.Err
}
}
}
func dialPlan9(net string, laddr, raddr Addr) (fd *netFD, err error) {
defer func() { netErr(err) }()
f, dest, proto, name, err := startPlan9(net, raddr)
if err != nil {
return nil, &OpError{"dial", net, raddr, err}
}
_, err = f.WriteString("connect " + dest)
if err != nil {
f.Close()
return nil, &OpError{"dial", f.Name(), raddr, err}
}
data, err := os.OpenFile(netdir+"/"+proto+"/"+name+"/data", os.O_RDWR, 0)
if err != nil {
f.Close()
return nil, &OpError{"dial", net, raddr, err}
}
laddr, err = readPlan9Addr(proto, netdir+"/"+proto+"/"+name+"/local")
if err != nil {
data.Close()
f.Close()
return nil, &OpError{"dial", proto, raddr, err}
}
return newFD(proto, name, f, data, laddr, raddr)
}
func listenPlan9(net string, laddr Addr) (fd *netFD, err error) {
defer func() { netErr(err) }()
f, dest, proto, name, err := startPlan9(net, laddr)
if err != nil {
return nil, &OpError{"listen", net, laddr, err}
}
_, err = f.WriteString("announce " + dest)
if err != nil {
f.Close()
return nil, &OpError{"announce", proto, laddr, err}
}
laddr, err = readPlan9Addr(proto, netdir+"/"+proto+"/"+name+"/local")
if err != nil {
f.Close()
return nil, &OpError{Op: "listen", Net: net, Err: err}
}
return newFD(proto, name, f, nil, laddr, nil)
}
func (l *netFD) netFD() (*netFD, error) {
return newFD(l.proto, l.n, l.ctl, l.data, l.laddr, l.raddr)
}
func (l *netFD) acceptPlan9() (fd *netFD, err error) {
defer func() { netErr(err) }()
if err := l.readLock(); err != nil {
return nil, err
}
defer l.readUnlock()
f, err := os.Open(l.dir + "/listen")
if err != nil {
return nil, &OpError{"accept", l.dir + "/listen", l.laddr, err}
}
var buf [16]byte
n, err := f.Read(buf[:])
if err != nil {
f.Close()
return nil, &OpError{"accept", l.dir + "/listen", l.laddr, err}
}
name := string(buf[:n])
data, err := os.OpenFile(netdir+"/"+l.proto+"/"+name+"/data", os.O_RDWR, 0)
if err != nil {
f.Close()
return nil, &OpError{"accept", l.proto, l.laddr, err}
}
raddr, err := readPlan9Addr(l.proto, netdir+"/"+l.proto+"/"+name+"/remote")
if err != nil {
data.Close()
f.Close()
return nil, &OpError{"accept", l.proto, l.laddr, err}
}
return newFD(l.proto, name, f, data, l.laddr, raddr)
}