github.com/m10x/go/src@v0.0.0-20220112094212-ba61592315da/net/rawconn.go (about) 1 // Copyright 2017 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 net 6 7 import ( 8 "runtime" 9 "syscall" 10 ) 11 12 // BUG(tmm1): On Windows, the Write method of syscall.RawConn 13 // does not integrate with the runtime's network poller. It cannot 14 // wait for the connection to become writeable, and does not respect 15 // deadlines. If the user-provided callback returns false, the Write 16 // method will fail immediately. 17 18 // BUG(mikio): On JS and Plan 9, the Control, Read and Write 19 // methods of syscall.RawConn are not implemented. 20 21 type rawConn struct { 22 fd *netFD 23 } 24 25 func (c *rawConn) ok() bool { return c != nil && c.fd != nil } 26 27 func (c *rawConn) Control(f func(uintptr)) error { 28 if !c.ok() { 29 return syscall.EINVAL 30 } 31 err := c.fd.pfd.RawControl(f) 32 runtime.KeepAlive(c.fd) 33 if err != nil { 34 err = &OpError{Op: "raw-control", Net: c.fd.net, Source: nil, Addr: c.fd.laddr, Err: err} 35 } 36 return err 37 } 38 39 func (c *rawConn) Read(f func(uintptr) bool) error { 40 if !c.ok() { 41 return syscall.EINVAL 42 } 43 err := c.fd.pfd.RawRead(f) 44 runtime.KeepAlive(c.fd) 45 if err != nil { 46 err = &OpError{Op: "raw-read", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err} 47 } 48 return err 49 } 50 51 func (c *rawConn) Write(f func(uintptr) bool) error { 52 if !c.ok() { 53 return syscall.EINVAL 54 } 55 err := c.fd.pfd.RawWrite(f) 56 runtime.KeepAlive(c.fd) 57 if err != nil { 58 err = &OpError{Op: "raw-write", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err} 59 } 60 return err 61 } 62 63 func newRawConn(fd *netFD) (*rawConn, error) { 64 return &rawConn{fd: fd}, nil 65 } 66 67 type rawListener struct { 68 rawConn 69 } 70 71 func (l *rawListener) Read(func(uintptr) bool) error { 72 return syscall.EINVAL 73 } 74 75 func (l *rawListener) Write(func(uintptr) bool) error { 76 return syscall.EINVAL 77 } 78 79 func newRawListener(fd *netFD) (*rawListener, error) { 80 return &rawListener{rawConn{fd: fd}}, nil 81 }