// Copyright 2009 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. //go:build unix || windows package net import ( "internal/bytealg" "runtime" "syscall" ) // Boolean to int. func boolint(b bool) int { if b { return 1 } return 0 } func interfaceToIPv4Addr(ifi *Interface) (IP, error) { if ifi == nil { return IPv4zero, nil } ifat, err := ifi.Addrs() if err != nil { return nil, err } for _, ifa := range ifat { switch v := ifa.(type) { case *IPAddr: if v.IP.To4() != nil { return v.IP, nil } case *IPNet: if v.IP.To4() != nil { return v.IP, nil } } } return nil, errNoSuchInterface } func setIPv4MreqToInterface(mreq *syscall.IPMreq, ifi *Interface) error { if ifi == nil { return nil } ifat, err := ifi.Addrs() if err != nil { return err } for _, ifa := range ifat { switch v := ifa.(type) { case *IPAddr: if a := v.IP.To4(); a != nil { copy(mreq.Interface[:], a) goto done } case *IPNet: if a := v.IP.To4(); a != nil { copy(mreq.Interface[:], a) goto done } } } done: if bytealg.Equal(mreq.Multiaddr[:], IPv4zero.To4()) { return errNoSuchMulticastInterface } return nil } func setReadBuffer(fd *netFD, bytes int) error { err := fd.pfd.SetsockoptInt(syscall.SOL_SOCKET, syscall.SO_RCVBUF, bytes) runtime.KeepAlive(fd) return wrapSyscallError("setsockopt", err) } func setWriteBuffer(fd *netFD, bytes int) error { err := fd.pfd.SetsockoptInt(syscall.SOL_SOCKET, syscall.SO_SNDBUF, bytes) runtime.KeepAlive(fd) return wrapSyscallError("setsockopt", err) } func setKeepAlive(fd *netFD, keepalive bool) error { err := fd.pfd.SetsockoptInt(syscall.SOL_SOCKET, syscall.SO_KEEPALIVE, boolint(keepalive)) runtime.KeepAlive(fd) return wrapSyscallError("setsockopt", err) } func setLinger(fd *netFD, sec int) error { var l syscall.Linger if sec >= 0 { l.Onoff = 1 l.Linger = int32(sec) } else { l.Onoff = 0 l.Linger = 0 } err := fd.pfd.SetsockoptLinger(syscall.SOL_SOCKET, syscall.SO_LINGER, &l) runtime.KeepAlive(fd) return wrapSyscallError("setsockopt", err) }