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package dhcp4client
import (
"net"
"time"
)
type inetSock struct {
*net.UDPConn
laddr net.UDPAddr
raddr net.UDPAddr
}
func NewInetSock(options ...func(*inetSock) error) (*inetSock, error) {
c := &inetSock{
laddr: net.UDPAddr{IP: net.IPv4(0, 0, 0, 0), Port: 68},
raddr: net.UDPAddr{IP: net.IPv4bcast, Port: 67},
}
err := c.setOption(options...)
if err != nil {
return nil, err
}
conn, err := net.ListenUDP("udp4", &c.laddr)
if err != nil {
return nil, err
}
c.UDPConn = conn
return c, err
}
func (c *inetSock) setOption(options ...func(*inetSock) error) error {
for _, opt := range options {
if err := opt(c); err != nil {
return err
}
}
return nil
}
func SetLocalAddr(l net.UDPAddr) func(*inetSock) error {
return func(c *inetSock) error {
c.laddr = l
return nil
}
}
func SetRemoteAddr(r net.UDPAddr) func(*inetSock) error {
return func(c *inetSock) error {
c.raddr = r
return nil
}
}
func (c *inetSock) Write(packet []byte) error {
_, err := c.WriteToUDP(packet, &c.raddr)
return err
}
func (c *inetSock) ReadFrom() ([]byte, net.IP, error) {
readBuffer := make([]byte, MaxDHCPLen)
n, source, err := c.ReadFromUDP(readBuffer)
if source != nil {
return readBuffer[:n], source.IP, err
} else {
return readBuffer[:n], net.IP{}, err
}
}
func (c *inetSock) SetReadTimeout(t time.Duration) error {
return c.SetReadDeadline(time.Now().Add(t))
}
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