net, syscall: Use native endianness for GNU/Linux netlink code.

[pf3gnuchains/gcc-fork.git] / libgo / go / net / interface_linux.go

diff --git a/libgo/go/net/interface_linux.go b/libgo/go/net/interface_linux.go
index 0d7017f..ce2e921 100644 (file)
--- a/libgo/go/net/interface_linux.go
+++ b/libgo/go/net/interface_linux.go
@@ -64,11 +64,7 @@ func newLink(ifim *syscall.IfInfomsg, attrs []syscall.NetlinkRouteAttr) Interfac
                case syscall.IFLA_IFNAME:
                        ifi.Name = string(a.Value[:len(a.Value)-1])
                case syscall.IFLA_MTU:
-                       if syscall.BigEndian {
-                               ifi.MTU = int(uint32(a.Value[0])<<24 | uint32(a.Value[1])<<16 | uint32(a.Value[2])<<8 | uint32(a.Value[3]))
-                       } else {
-                               ifi.MTU = int(uint32(a.Value[3])<<24 | uint32(a.Value[2])<<16 | uint32(a.Value[1])<<8 | uint32(a.Value[0]))
-                       }
+                       ifi.MTU = int(*(*uint32)(unsafe.Pointer(&a.Value[:4][0])))
                }
        }
        return ifi
@@ -197,15 +193,14 @@ func parseProcNetIGMP(path string, ifi *Interface) []Addr {
                        name = f[1]
                case len(f[0]) == 8:
                        if ifi == nil || name == ifi.Name {
+                               // The Linux kernel puts the IP
+                               // address in /proc/net/igmp in native
+                               // endianness.
                                for i := 0; i+1 < len(f[0]); i += 2 {
                                        b[i/2], _ = xtoi2(f[0][i:i+2], 0)
                                }
-                               var ifma IPAddr
-                               if syscall.BigEndian {
-                                       ifma = IPAddr{IP: IPv4(b[0], b[1], b[2], b[3])}
-                               } else {
-                                       ifma = IPAddr{IP: IPv4(b[3], b[2], b[1], b[0])}
-                               }
+                               i := *(*uint32)(unsafe.Pointer(&b[:4][0]))
+                               ifma := IPAddr{IP: IPv4(byte(i>>24), byte(i>>16), byte(i>>8), byte(i))}
                                ifmat = append(ifmat, ifma.toAddr())
                        }
                }