github.com/graybobo/golang.org-package-offline-cache@v0.0.0-20200626051047-6608995c132f/x/net/ipv6/helper_windows.go (about)

     1  // Copyright 2013 The Go Authors.  All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package ipv6
     6  
     7  import (
     8  	"net"
     9  	"reflect"
    10  	"syscall"
    11  )
    12  
    13  func (c *genericOpt) sysfd() (syscall.Handle, error) {
    14  	switch p := c.Conn.(type) {
    15  	case *net.TCPConn, *net.UDPConn, *net.IPConn:
    16  		return sysfd(p)
    17  	}
    18  	return syscall.InvalidHandle, errInvalidConnType
    19  }
    20  
    21  func (c *dgramOpt) sysfd() (syscall.Handle, error) {
    22  	switch p := c.PacketConn.(type) {
    23  	case *net.UDPConn, *net.IPConn:
    24  		return sysfd(p.(net.Conn))
    25  	}
    26  	return syscall.InvalidHandle, errInvalidConnType
    27  }
    28  
    29  func (c *payloadHandler) sysfd() (syscall.Handle, error) {
    30  	return sysfd(c.PacketConn.(net.Conn))
    31  }
    32  
    33  func sysfd(c net.Conn) (syscall.Handle, error) {
    34  	cv := reflect.ValueOf(c)
    35  	switch ce := cv.Elem(); ce.Kind() {
    36  	case reflect.Struct:
    37  		netfd := ce.FieldByName("conn").FieldByName("fd")
    38  		switch fe := netfd.Elem(); fe.Kind() {
    39  		case reflect.Struct:
    40  			fd := fe.FieldByName("sysfd")
    41  			return syscall.Handle(fd.Uint()), nil
    42  		}
    43  	}
    44  	return syscall.InvalidHandle, errInvalidConnType
    45  }