unix: add Ioctl{Get,Set}IfreqMTU on darwin
For golang/go#41868
Change-Id: I9fb8f5eee933488e4c63aaa757059b8cea4d9629
Reviewed-on: https://go-review.googlesource.com/c/sys/+/264637
Trust: Tobias Klauser <tobias.klauser@gmail.com>
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
Reviewed-by: Matt Layher <mdlayher@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
diff --git a/unix/syscall_darwin.go b/unix/syscall_darwin.go
index 5b0e831..7fc58d6 100644
--- a/unix/syscall_darwin.go
+++ b/unix/syscall_darwin.go
@@ -264,6 +264,29 @@
return err
}
+// IfreqMTU is struct ifreq used to get or set a network device's MTU.
+type IfreqMTU struct {
+ Name [IFNAMSIZ]byte
+ MTU int32
+}
+
+// IoctlGetIfreqMTU performs the SIOCGIFMTU ioctl operation on fd to get the MTU
+// of the network device specified by ifname.
+func IoctlGetIfreqMTU(fd int, ifname string) (*IfreqMTU, error) {
+ var ifreq IfreqMTU
+ copy(ifreq.Name[:], ifname)
+ err := ioctl(fd, SIOCGIFMTU, uintptr(unsafe.Pointer(&ifreq)))
+ return &ifreq, err
+}
+
+// IoctlSetIfreqMTU performs the SIOCSIFMTU ioctl operation on fd to set the MTU
+// of the network device specified by ifreq.Name.
+func IoctlSetIfreqMTU(fd int, ifreq *IfreqMTU) error {
+ err := ioctl(fd, SIOCSIFMTU, uintptr(unsafe.Pointer(ifreq)))
+ runtime.KeepAlive(ifreq)
+ return err
+}
+
//sys sysctl(mib []_C_int, old *byte, oldlen *uintptr, new *byte, newlen uintptr) (err error) = SYS_SYSCTL
func Uname(uname *Utsname) error {
