syscall: add network interface announce support on BSD variants
This CL allows to receive network interface arrival and depature
notifications through routing sockets on BSD variants. So far
Darwin doesn't support this feature.
Also does small simplification.
Update #4866.
R=golang-dev, lucio.dere, dave
CC=golang-dev
https://golang.org/cl/7365055
diff --git a/src/pkg/syscall/route_bsd.go b/src/pkg/syscall/route_bsd.go
index e17d976..62c5ce1 100644
--- a/src/pkg/syscall/route_bsd.go
+++ b/src/pkg/syscall/route_bsd.go
@@ -8,9 +8,7 @@
package syscall
-import (
- "unsafe"
-)
+import "unsafe"
// Round the length of a raw sockaddr up to align it properly.
func rsaAlignOf(salen int) int {
@@ -31,7 +29,6 @@
// parameters.
func RouteRIB(facility, param int) ([]byte, error) {
mib := []_C_int{CTL_NET, AF_ROUTE, 0, 0, _C_int(facility), _C_int(param)}
-
// Find size.
n := uintptr(0)
if err := sysctl(mib, nil, &n, nil, 0); err != nil {
@@ -40,12 +37,10 @@
if n == 0 {
return nil, nil
}
-
tab := make([]byte, n)
if err := sysctl(mib, &tab[0], &n, nil, 0); err != nil {
return nil, err
}
-
return tab[:n], nil
}
@@ -76,13 +71,12 @@
af int
sas [4]Sockaddr
)
-
- buf := m.Data[:]
+ b := m.Data[:]
for i := uint(0); i < RTAX_MAX; i++ {
if m.Header.Addrs&rtaRtMask&(1<<i) == 0 {
continue
}
- rsa := (*RawSockaddr)(unsafe.Pointer(&buf[0]))
+ rsa := (*RawSockaddr)(unsafe.Pointer(&b[0]))
switch i {
case RTAX_DST, RTAX_GATEWAY:
sa, err := anyToSockaddr((*RawSockaddrAny)(unsafe.Pointer(rsa)))
@@ -96,14 +90,14 @@
case RTAX_NETMASK, RTAX_GENMASK:
switch af {
case AF_INET:
- rsa4 := (*RawSockaddrInet4)(unsafe.Pointer(&buf[0]))
+ rsa4 := (*RawSockaddrInet4)(unsafe.Pointer(&b[0]))
sa := new(SockaddrInet4)
for j := 0; rsa4.Len > 0 && j < int(rsa4.Len)-int(unsafe.Offsetof(rsa4.Addr)); j++ {
sa.Addr[j] = rsa4.Addr[j]
}
sas[i] = sa
case AF_INET6:
- rsa6 := (*RawSockaddrInet6)(unsafe.Pointer(&buf[0]))
+ rsa6 := (*RawSockaddrInet6)(unsafe.Pointer(&b[0]))
sa := new(SockaddrInet6)
for j := 0; rsa6.Len > 0 && j < int(rsa6.Len)-int(unsafe.Offsetof(rsa6.Addr)); j++ {
sa.Addr[j] = rsa6.Addr[j]
@@ -111,9 +105,8 @@
sas[i] = sa
}
}
- buf = buf[rsaAlignOf(int(rsa.Len)):]
+ b = b[rsaAlignOf(int(rsa.Len)):]
}
-
return sas[:]
}
@@ -148,13 +141,12 @@
if m.Header.Addrs&rtaIfaMask == 0 {
return nil
}
-
- buf := m.Data[:]
+ b := m.Data[:]
for i := uint(0); i < RTAX_MAX; i++ {
if m.Header.Addrs&rtaIfaMask&(1<<i) == 0 {
continue
}
- rsa := (*RawSockaddr)(unsafe.Pointer(&buf[0]))
+ rsa := (*RawSockaddr)(unsafe.Pointer(&b[0]))
switch i {
case RTAX_IFA:
sa, err := anyToSockaddr((*RawSockaddrAny)(unsafe.Pointer(rsa)))
@@ -174,22 +166,21 @@
case RTAX_BRD:
// nothing to do
}
- buf = buf[rsaAlignOf(int(rsa.Len)):]
+ b = b[rsaAlignOf(int(rsa.Len)):]
}
-
return sas
}
-// ParseRoutingMessage parses buf as routing messages and returns
-// the slice containing the RoutingMessage interfaces.
-func ParseRoutingMessage(buf []byte) (msgs []RoutingMessage, err error) {
- for len(buf) >= anyMessageLen {
- any := (*anyMessage)(unsafe.Pointer(&buf[0]))
+// ParseRoutingMessage parses b as routing messages and returns the
+// slice containing the RoutingMessage interfaces.
+func ParseRoutingMessage(b []byte) (msgs []RoutingMessage, err error) {
+ for len(b) >= anyMessageLen {
+ any := (*anyMessage)(unsafe.Pointer(&b[0]))
if any.Version != RTM_VERSION {
return nil, EINVAL
}
- msgs = append(msgs, any.toRoutingMessage(buf))
- buf = buf[any.Msglen:]
+ msgs = append(msgs, any.toRoutingMessage(b))
+ b = b[any.Msglen:]
}
return msgs, nil
}
