/
conn.go
82 lines (63 loc) · 1.36 KB
/
conn.go
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package lwes
import (
"net"
)
type Conn struct {
addr *net.UDPAddr
iface *net.Interface
socket *net.UDPConn
}
// Bind starts listening on udp addr.
// if emitter is true, bind to :0 and write to c.addr
// else bind to c.addr and read from c.addr
func (c *Conn) Bind(emitter bool) error {
var addr *net.UDPAddr
var conn *net.UDPConn
var err error
if emitter {
addr, err = net.ResolveUDPAddr("udp", ":0")
} else {
addr = c.addr
}
if err != nil {
return err
}
if addr.IP != nil && addr.IP.IsMulticast() {
conn, err = net.ListenMulticastUDP("udp", nil, addr)
} else {
conn, err = net.ListenUDP("udp", addr)
}
if err != nil {
return err
}
c.socket = conn
return nil
}
// Close closes the socket. Make sure to call this if calling bind explicitely.
func (c *Conn) Close() {
if c.socket != nil {
c.socket.Close()
}
}
func (c *Conn) Read(b []byte) (int, *net.UDPAddr, error) {
return c.socket.ReadFromUDP(b)
}
func (c *Conn) Write(b []byte) (int, error) {
return c.socket.WriteToUDP(b, c.addr)
}
func NewConn(udp string, emitter bool, iface ...*net.Interface) (*Conn, error) {
addr, err := net.ResolveUDPAddr("udp", udp)
if err != nil {
return nil, err
}
var ifi *net.Interface
if iface != nil {
ifi = iface[0]
}
c := &Conn{addr: addr, iface: ifi}
err = c.Bind(emitter)
if err != nil {
return nil, err
}
return c, nil
}