golang rawconn_unix_test 代码
文件路径：/src/net/rawconn_unix_test.go
/ Copyright 2017 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
package net
import (
"errors"
"syscall"
)
func readRawConn(c syscall.RawConn, b []byte) (int, error) {
var operr error
var n int
err := c.Read(func(s uintptr) bool {
n, operr = syscall.Read(int(s), b)
if operr == syscall.EAGAIN {
return false
}
return true
})
if err != nil {
return n, err
}
return n, operr
}
func writeRawConn(c syscall.RawConn, b []byte) error {
var operr error
err := c.Write(func(s uintptr) bool {
_, operr = syscall.Write(int(s), b)
if operr == syscall.EAGAIN {
return false
}
return true
})
if err != nil {
return err
}
return operr
}
func controlRawConn(c syscall.RawConn, addr Addr) error {
var operr error
fn := func(s uintptr) {
_, operr = syscall.GetsockoptInt(int(s), syscall.SOL_SOCKET, syscall.SO_REUSEADDR)
if operr != nil {
return
}
switch addr := addr.(type) {
case *TCPAddr:
/ There's no guarantee that IP-level socket
/ options work well with dual stack sockets.
/ A simple solution would be to take a look
/ at the bound address to the raw connection
/ and to classify the address family of the
/ underlying socket by the bound address:
/
/ - When IP.To16() != nil and IP.To4() == nil,
/ we can assume that the raw connection
/ consists of an IPv6 socket using only
/ IPv6 addresses.
/
/ - When IP.To16() == nil and IP.To4() != nil,
/ the raw connection consists of an IPv4
/ socket using only IPv4 addresses.
/
/ - Otherwise, the raw connection is a dual
/ stack socket, an IPv6 socket using IPv6
/ addresses including IPv4-mapped or
/ IPv4-embedded IPv6 addresses.
if addr.IP.To16() != nil && addr.IP.To4() == nil {
operr = syscall.SetsockoptInt(int(s), syscall.IPPROTO_IPV6, syscall.IPV6_UNICAST_HOPS, 1)
} else if addr.IP.To16() == nil && addr.IP.To4() != nil {
operr = syscall.SetsockoptInt(int(s), syscall.IPPROTO_IP, syscall.IP_TTL, 1)
}
}
}
if err := c.Control(fn); err != nil {
return err
}
return operr
}
func controlOnConnSetup(network string, address string, c syscall.RawConn) error {
var operr error
var fn func(uintptr)
switch network {
case "tcp", "udp", "ip":
return errors.New("ambiguous network: " + network)
case "unix", "unixpacket", "unixgram":
fn = func(s uintptr) {
_, operr = syscall.GetsockoptInt(int(s), syscall.SOL_SOCKET, syscall.SO_ERROR)
}
default:
switch network[len(network)-1] {
case '4':
fn = func(s uintptr) {
operr = syscall.SetsockoptInt(int(s), syscall.IPPROTO_IP, syscall.IP_TTL, 1)
}
case '6':
fn = func(s uintptr) {
operr = syscall.SetsockoptInt(int(s), syscall.IPPROTO_IPV6, syscall.IPV6_UNICAST_HOPS, 1)
}
default:
return errors.New("unknown network: " + network)
}
}
if err := c.Control(fn); err != nil {
return err
}
return operr
}