code review 19940044: go.net/ipv6: implement getsockopt, setsockopt syscalls

ipv6/sys_darwin.go

Index: ipv6/sys_darwin.go
===================================================================
new file mode 100644
--- /dev/null
+++ b/ipv6/sys_darwin.go
@@ -0,0 +1,54 @@
+// Copyright 2013 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 ipv6
+
+import (
+	"net"
+	"syscall"
+)
+
+// RFC 2292 options
+const (
+	// See /usr/include/netinet6/in6.h.
+	sysSockopt2292HopLimit   = 0x14
+	sysSockopt2292PacketInfo = 0x13
+	sysSockopt2292NextHop    = 0x15
+)
+
+// RFC 3493 options
+const (
+	// See /usr/include/netinet6/in6.h.
+	sysSockoptUnicastHopLimit    = 0x4
+	sysSockoptMulticastHopLimit  = 0xa
+	sysSockoptMulticastInterface = 0x9
+	sysSockoptMulticastLoopback  = 0xb
+	sysSockoptJoinGroup          = 0xc
+	sysSockoptLeaveGroup         = 0xd
+)
+
+// RFC 3542 options
+const (
+	// See /usr/include/netinet6/in6.h.
+	sysSockoptReceiveTrafficClass = 0x23
+	sysSockoptTrafficClass        = 0x24
+	sysSockoptReceiveHopLimit     = 0x25
+	sysSockoptHopLimit            = 0x2f
+	sysSockoptReceivePacketInfo   = 0x3d
+	sysSockoptPacketInfo          = 0x2e
+	sysSockoptReceivePathMTU      = 0x2b
+	sysSockoptPathMTU             = 0x2c
+	sysSockoptNextHop             = 0x30
+	sysSockoptChecksum            = 0x1a
+
+	// See /usr/include/netinet6/in6.h.
+	sysSockoptICMPFilter = 0x12
+)
+
+func setSockaddr(sa *syscall.RawSockaddrInet6, ip net.IP, ifindex int) {
+	sa.Len = syscall.SizeofSockaddrInet6
+	sa.Family = syscall.AF_INET6
+	copy(sa.Addr[:], ip)
+	sa.Scope_id = uint32(ifindex)
+}