| // Copyright 2012 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. |
| |
| // +build js nacl plan9 windows |
| |
| package ipv4 |
| |
| import "net" |
| |
| // ReadFrom reads a payload of the received IPv4 datagram, from the |
| // endpoint c, copying the payload into b. It returns the number of |
| // bytes copied into b, the control message cm and the source address |
| // src of the received datagram. |
| func (c *payloadHandler) ReadFrom(b []byte) (n int, cm *ControlMessage, src net.Addr, err error) { |
| if !c.ok() { |
| return 0, nil, nil, errInvalidConn |
| } |
| if n, src, err = c.PacketConn.ReadFrom(b); err != nil { |
| return 0, nil, nil, err |
| } |
| return |
| } |
| |
| // WriteTo writes a payload of the IPv4 datagram, to the destination |
| // address dst through the endpoint c, copying the payload from b. It |
| // returns the number of bytes written. The control message cm allows |
| // the datagram path and the outgoing interface to be specified. |
| // Currently only Darwin and Linux support this. The cm may be nil if |
| // control of the outgoing datagram is not required. |
| func (c *payloadHandler) WriteTo(b []byte, cm *ControlMessage, dst net.Addr) (n int, err error) { |
| if !c.ok() { |
| return 0, errInvalidConn |
| } |
| if dst == nil { |
| return 0, errMissingAddress |
| } |
| return c.PacketConn.WriteTo(b, dst) |
| } |