Imported Upstream version 1.4upstream/1.4

1 files changed, 126 insertions, 0 deletions

diff --git a/src/net/interface.go b/src/net/interface.go
new file mode 100644
index 000000000..2e9f1ebc6
--- /dev/null
+++ b/src/net/interface.go
@@ -0,0 +1,126 @@
+// Copyright 2011 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 "errors"
+
+var (
+	errInvalidInterface         = errors.New("invalid network interface")
+	errInvalidInterfaceIndex    = errors.New("invalid network interface index")
+	errInvalidInterfaceName     = errors.New("invalid network interface name")
+	errNoSuchInterface          = errors.New("no such network interface")
+	errNoSuchMulticastInterface = errors.New("no such multicast network interface")
+)
+
+// Interface represents a mapping between network interface name
+// and index.  It also represents network interface facility
+// information.
+type Interface struct {
+	Index        int          // positive integer that starts at one, zero is never used
+	MTU          int          // maximum transmission unit
+	Name         string       // e.g., "en0", "lo0", "eth0.100"
+	HardwareAddr HardwareAddr // IEEE MAC-48, EUI-48 and EUI-64 form
+	Flags        Flags        // e.g., FlagUp, FlagLoopback, FlagMulticast
+}
+
+type Flags uint
+
+const (
+	FlagUp           Flags = 1 << iota // interface is up
+	FlagBroadcast                      // interface supports broadcast access capability
+	FlagLoopback                       // interface is a loopback interface
+	FlagPointToPoint                   // interface belongs to a point-to-point link
+	FlagMulticast                      // interface supports multicast access capability
+)
+
+var flagNames = []string{
+	"up",
+	"broadcast",
+	"loopback",
+	"pointtopoint",
+	"multicast",
+}
+
+func (f Flags) String() string {
+	s := ""
+	for i, name := range flagNames {
+		if f&(1<<uint(i)) != 0 {
+			if s != "" {
+				s += "|"
+			}
+			s += name
+		}
+	}
+	if s == "" {
+		s = "0"
+	}
+	return s
+}
+
+// Addrs returns interface addresses for a specific interface.
+func (ifi *Interface) Addrs() ([]Addr, error) {
+	if ifi == nil {
+		return nil, errInvalidInterface
+	}
+	return interfaceAddrTable(ifi)
+}
+
+// MulticastAddrs returns multicast, joined group addresses for
+// a specific interface.
+func (ifi *Interface) MulticastAddrs() ([]Addr, error) {
+	if ifi == nil {
+		return nil, errInvalidInterface
+	}
+	return interfaceMulticastAddrTable(ifi)
+}
+
+// Interfaces returns a list of the system's network interfaces.
+func Interfaces() ([]Interface, error) {
+	return interfaceTable(0)
+}
+
+// InterfaceAddrs returns a list of the system's network interface
+// addresses.
+func InterfaceAddrs() ([]Addr, error) {
+	return interfaceAddrTable(nil)
+}
+
+// InterfaceByIndex returns the interface specified by index.
+func InterfaceByIndex(index int) (*Interface, error) {
+	if index <= 0 {
+		return nil, errInvalidInterfaceIndex
+	}
+	ift, err := interfaceTable(index)
+	if err != nil {
+		return nil, err
+	}
+	return interfaceByIndex(ift, index)
+}
+
+func interfaceByIndex(ift []Interface, index int) (*Interface, error) {
+	for _, ifi := range ift {
+		if index == ifi.Index {
+			return &ifi, nil
+		}
+	}
+	return nil, errNoSuchInterface
+}
+
+// InterfaceByName returns the interface specified by name.
+func InterfaceByName(name string) (*Interface, error) {
+	if name == "" {
+		return nil, errInvalidInterfaceName
+	}
+	ift, err := interfaceTable(0)
+	if err != nil {
+		return nil, err
+	}
+	for _, ifi := range ift {
+		if name == ifi.Name {
+			return &ifi, nil
+		}
+	}
+	return nil, errNoSuchInterface
+}