Update Go library to r60.

From-SVN: r178910

1 files changed, 174 insertions, 0 deletions

diff --git a/libgo/go/net/ipsock_posix.go b/libgo/go/net/ipsock_posix.go
new file mode 100644
index 0000000..0c522fb
--- /dev/null
+++ b/libgo/go/net/ipsock_posix.go
@@ -0,0 +1,174 @@
+// 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.
+
+package net
+
+import (
+	"os"
+	"syscall"
+)
+
+// Should we try to use the IPv4 socket interface if we're
+// only dealing with IPv4 sockets?  As long as the host system
+// understands IPv6, it's okay to pass IPv4 addresses to the IPv6
+// interface.  That simplifies our code and is most general.
+// Unfortunately, we need to run on kernels built without IPv6
+// support too.  So probe the kernel to figure it out.
+//
+// probeIPv6Stack probes both basic IPv6 capability and IPv6 IPv4-
+// mapping capability which is controlled by IPV6_V6ONLY socket
+// option and/or kernel state "net.inet6.ip6.v6only".
+// It 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) {
+	var probes = []struct {
+		la TCPAddr
+		ok bool
+	}{
+		// IPv6 communication capability
+		{TCPAddr{IP: ParseIP("::1")}, false},
+		// IPv6 IPv4-mapped address communication capability
+		{TCPAddr{IP: IPv4(127, 0, 0, 1)}, false},
+	}
+
+	for i := range probes {
+		s, errno := syscall.Socket(syscall.AF_INET6, syscall.SOCK_STREAM, syscall.IPPROTO_TCP)
+		if errno != 0 {
+			continue
+		}
+		defer closesocket(s)
+		sa, err := probes[i].la.toAddr().sockaddr(syscall.AF_INET6)
+		if err != nil {
+			continue
+		}
+		errno = syscall.Bind(s, sa)
+		if errno != 0 {
+			continue
+		}
+		probes[i].ok = true
+	}
+
+	return probes[0].ok, probes[1].ok
+}
+
+// favoriteAddrFamily returns the appropriate address family to
+// the given net, raddr, laddr and mode.  At first it figures
+// address family out from the net.  If mode indicates "listen"
+// and laddr.(type).IP is nil, it assumes that the user wants to
+// make a passive connection with wildcard address family, both
+// INET and INET6, and wildcard address.  Otherwise guess: if the
+// addresses are IPv4 then returns INET, or else returns INET6.
+func favoriteAddrFamily(net string, raddr, laddr sockaddr, mode string) int {
+	switch net[len(net)-1] {
+	case '4':
+		return syscall.AF_INET
+	case '6':
+		return syscall.AF_INET6
+	}
+
+	if mode == "listen" {
+		switch a := laddr.(type) {
+		case *TCPAddr:
+			if a.IP == nil && supportsIPv6 {
+				return syscall.AF_INET6
+			}
+		case *UDPAddr:
+			if a.IP == nil && supportsIPv6 {
+				return syscall.AF_INET6
+			}
+		case *IPAddr:
+			if a.IP == nil && supportsIPv6 {
+				return syscall.AF_INET6
+			}
+		}
+	}
+
+	if (laddr == nil || laddr.family() == syscall.AF_INET) &&
+		(raddr == nil || raddr.family() == syscall.AF_INET) {
+		return syscall.AF_INET
+	}
+	return syscall.AF_INET6
+}
+
+// TODO(rsc): if syscall.OS == "linux", we're supposed to read
+// /proc/sys/net/core/somaxconn,
+// to take advantage of kernels that have raised the limit.
+func listenBacklog() int { return syscall.SOMAXCONN }
+
+// Internet sockets (TCP, UDP)
+
+// A sockaddr represents a TCP or UDP network address that can
+// be converted into a syscall.Sockaddr.
+type sockaddr interface {
+	Addr
+	sockaddr(family int) (syscall.Sockaddr, os.Error)
+	family() int
+}
+
+func internetSocket(net string, laddr, raddr sockaddr, socktype, proto int, mode string, toAddr func(syscall.Sockaddr) Addr) (fd *netFD, err os.Error) {
+	var oserr os.Error
+	var la, ra syscall.Sockaddr
+	family := favoriteAddrFamily(net, raddr, laddr, mode)
+	if laddr != nil {
+		if la, oserr = laddr.sockaddr(family); oserr != nil {
+			goto Error
+		}
+	}
+	if raddr != nil {
+		if ra, oserr = raddr.sockaddr(family); oserr != nil {
+			goto Error
+		}
+	}
+	fd, oserr = socket(net, family, socktype, proto, la, ra, toAddr)
+	if oserr != nil {
+		goto Error
+	}
+	return fd, nil
+
+Error:
+	addr := raddr
+	if mode == "listen" {
+		addr = laddr
+	}
+	return nil, &OpError{mode, net, addr, oserr}
+}
+
+func ipToSockaddr(family int, ip IP, port int) (syscall.Sockaddr, os.Error) {
+	switch family {
+	case syscall.AF_INET:
+		if len(ip) == 0 {
+			ip = IPv4zero
+		}
+		if ip = ip.To4(); ip == nil {
+			return nil, InvalidAddrError("non-IPv4 address")
+		}
+		s := new(syscall.SockaddrInet4)
+		for i := 0; i < IPv4len; i++ {
+			s.Addr[i] = ip[i]
+		}
+		s.Port = port
+		return s, nil
+	case syscall.AF_INET6:
+		if len(ip) == 0 {
+			ip = IPv6zero
+		}
+		// IPv4 callers use 0.0.0.0 to mean "announce on any available address".
+		// In IPv6 mode, Linux treats that as meaning "announce on 0.0.0.0",
+		// which it refuses to do.  Rewrite to the IPv6 all zeros.
+		if ip.Equal(IPv4zero) {
+			ip = IPv6zero
+		}
+		if ip = ip.To16(); ip == nil {
+			return nil, InvalidAddrError("non-IPv6 address")
+		}
+		s := new(syscall.SockaddrInet6)
+		for i := 0; i < IPv6len; i++ {
+			s.Addr[i] = ip[i]
+		}
+		s.Port = port
+		return s, nil
+	}
+	return nil, InvalidAddrError("unexpected socket family")
+}