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1 // Copyright 2009 The Go Authors. All rights reserved.
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2 // Use of this source code is governed by a BSD-style
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3 // license that can be found in the LICENSE file.
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4
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5 //go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
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6 // +build aix darwin dragonfly freebsd linux netbsd openbsd solaris
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7
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8 package unix
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9
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10 import (
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11 "bytes"
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12 "sort"
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13 "sync"
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14 "syscall"
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15 "unsafe"
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16 )
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17
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18 var (
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19 Stdin = 0
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20 Stdout = 1
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21 Stderr = 2
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22 )
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23
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24 // Do the interface allocations only once for common
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25 // Errno values.
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26 var (
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27 errEAGAIN error = syscall.EAGAIN
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28 errEINVAL error = syscall.EINVAL
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29 errENOENT error = syscall.ENOENT
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30 )
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31
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32 var (
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33 signalNameMapOnce sync.Once
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34 signalNameMap map[string]syscall.Signal
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35 )
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36
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37 // errnoErr returns common boxed Errno values, to prevent
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38 // allocations at runtime.
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39 func errnoErr(e syscall.Errno) error {
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40 switch e {
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41 case 0:
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42 return nil
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43 case EAGAIN:
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44 return errEAGAIN
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45 case EINVAL:
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46 return errEINVAL
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47 case ENOENT:
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48 return errENOENT
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49 }
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50 return e
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51 }
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52
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53 // ErrnoName returns the error name for error number e.
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54 func ErrnoName(e syscall.Errno) string {
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55 i := sort.Search(len(errorList), func(i int) bool {
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56 return errorList[i].num >= e
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57 })
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58 if i < len(errorList) && errorList[i].num == e {
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59 return errorList[i].name
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60 }
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61 return ""
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62 }
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63
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64 // SignalName returns the signal name for signal number s.
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65 func SignalName(s syscall.Signal) string {
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66 i := sort.Search(len(signalList), func(i int) bool {
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67 return signalList[i].num >= s
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68 })
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69 if i < len(signalList) && signalList[i].num == s {
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70 return signalList[i].name
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71 }
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72 return ""
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73 }
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74
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75 // SignalNum returns the syscall.Signal for signal named s,
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76 // or 0 if a signal with such name is not found.
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77 // The signal name should start with "SIG".
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78 func SignalNum(s string) syscall.Signal {
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79 signalNameMapOnce.Do(func() {
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80 signalNameMap = make(map[string]syscall.Signal, len(signalList))
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81 for _, signal := range signalList {
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82 signalNameMap[signal.name] = signal.num
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83 }
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84 })
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85 return signalNameMap[s]
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86 }
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87
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88 // clen returns the index of the first NULL byte in n or len(n) if n contains no NULL byte.
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89 func clen(n []byte) int {
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90 i := bytes.IndexByte(n, 0)
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91 if i == -1 {
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92 i = len(n)
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93 }
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94 return i
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95 }
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96
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97 // Mmap manager, for use by operating system-specific implementations.
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98
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99 type mmapper struct {
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100 sync.Mutex
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101 active map[*byte][]byte // active mappings; key is last byte in mapping
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102 mmap func(addr, length uintptr, prot, flags, fd int, offset int64) (uintptr, error)
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103 munmap func(addr uintptr, length uintptr) error
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104 }
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105
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106 func (m *mmapper) Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) {
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107 if length <= 0 {
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108 return nil, EINVAL
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109 }
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110
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111 // Map the requested memory.
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112 addr, errno := m.mmap(0, uintptr(length), prot, flags, fd, offset)
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113 if errno != nil {
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114 return nil, errno
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115 }
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116
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117 // Use unsafe to convert addr into a []byte.
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118 b := unsafe.Slice((*byte)(unsafe.Pointer(addr)), length)
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66
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119
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120 // Register mapping in m and return it.
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121 p := &b[cap(b)-1]
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122 m.Lock()
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123 defer m.Unlock()
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124 m.active[p] = b
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125 return b, nil
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126 }
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127
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128 func (m *mmapper) Munmap(data []byte) (err error) {
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129 if len(data) == 0 || len(data) != cap(data) {
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130 return EINVAL
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131 }
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132
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133 // Find the base of the mapping.
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134 p := &data[cap(data)-1]
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135 m.Lock()
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136 defer m.Unlock()
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137 b := m.active[p]
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138 if b == nil || &b[0] != &data[0] {
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139 return EINVAL
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140 }
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141
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142 // Unmap the memory and update m.
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143 if errno := m.munmap(uintptr(unsafe.Pointer(&b[0])), uintptr(len(b))); errno != nil {
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144 return errno
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145 }
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146 delete(m.active, p)
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147 return nil
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148 }
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149
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150 func Read(fd int, p []byte) (n int, err error) {
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151 n, err = read(fd, p)
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152 if raceenabled {
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153 if n > 0 {
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154 raceWriteRange(unsafe.Pointer(&p[0]), n)
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155 }
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156 if err == nil {
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157 raceAcquire(unsafe.Pointer(&ioSync))
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158 }
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159 }
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160 return
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161 }
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162
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163 func Write(fd int, p []byte) (n int, err error) {
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164 if raceenabled {
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165 raceReleaseMerge(unsafe.Pointer(&ioSync))
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166 }
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167 n, err = write(fd, p)
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168 if raceenabled && n > 0 {
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169 raceReadRange(unsafe.Pointer(&p[0]), n)
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170 }
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171 return
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172 }
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173
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174 func Pread(fd int, p []byte, offset int64) (n int, err error) {
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175 n, err = pread(fd, p, offset)
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176 if raceenabled {
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177 if n > 0 {
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178 raceWriteRange(unsafe.Pointer(&p[0]), n)
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179 }
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180 if err == nil {
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181 raceAcquire(unsafe.Pointer(&ioSync))
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182 }
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183 }
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184 return
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185 }
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186
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187 func Pwrite(fd int, p []byte, offset int64) (n int, err error) {
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188 if raceenabled {
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189 raceReleaseMerge(unsafe.Pointer(&ioSync))
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190 }
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191 n, err = pwrite(fd, p, offset)
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192 if raceenabled && n > 0 {
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193 raceReadRange(unsafe.Pointer(&p[0]), n)
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194 }
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195 return
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196 }
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197
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198 // For testing: clients can set this flag to force
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199 // creation of IPv6 sockets to return EAFNOSUPPORT.
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200 var SocketDisableIPv6 bool
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201
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202 // Sockaddr represents a socket address.
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203 type Sockaddr interface {
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204 sockaddr() (ptr unsafe.Pointer, len _Socklen, err error) // lowercase; only we can define Sockaddrs
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205 }
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206
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207 // SockaddrInet4 implements the Sockaddr interface for AF_INET type sockets.
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208 type SockaddrInet4 struct {
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209 Port int
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210 Addr [4]byte
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211 raw RawSockaddrInet4
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212 }
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213
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214 // SockaddrInet6 implements the Sockaddr interface for AF_INET6 type sockets.
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215 type SockaddrInet6 struct {
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216 Port int
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217 ZoneId uint32
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218 Addr [16]byte
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219 raw RawSockaddrInet6
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220 }
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221
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222 // SockaddrUnix implements the Sockaddr interface for AF_UNIX type sockets.
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223 type SockaddrUnix struct {
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224 Name string
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225 raw RawSockaddrUnix
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226 }
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227
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228 func Bind(fd int, sa Sockaddr) (err error) {
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229 ptr, n, err := sa.sockaddr()
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230 if err != nil {
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231 return err
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232 }
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233 return bind(fd, ptr, n)
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234 }
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235
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236 func Connect(fd int, sa Sockaddr) (err error) {
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237 ptr, n, err := sa.sockaddr()
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238 if err != nil {
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239 return err
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240 }
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241 return connect(fd, ptr, n)
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242 }
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243
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244 func Getpeername(fd int) (sa Sockaddr, err error) {
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245 var rsa RawSockaddrAny
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246 var len _Socklen = SizeofSockaddrAny
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247 if err = getpeername(fd, &rsa, &len); err != nil {
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248 return
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249 }
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250 return anyToSockaddr(fd, &rsa)
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251 }
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252
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253 func GetsockoptByte(fd, level, opt int) (value byte, err error) {
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254 var n byte
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255 vallen := _Socklen(1)
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256 err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen)
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257 return n, err
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258 }
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259
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260 func GetsockoptInt(fd, level, opt int) (value int, err error) {
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261 var n int32
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262 vallen := _Socklen(4)
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263 err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen)
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264 return int(n), err
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265 }
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266
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267 func GetsockoptInet4Addr(fd, level, opt int) (value [4]byte, err error) {
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268 vallen := _Socklen(4)
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269 err = getsockopt(fd, level, opt, unsafe.Pointer(&value[0]), &vallen)
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270 return value, err
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271 }
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272
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273 func GetsockoptIPMreq(fd, level, opt int) (*IPMreq, error) {
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274 var value IPMreq
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275 vallen := _Socklen(SizeofIPMreq)
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276 err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
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277 return &value, err
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278 }
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279
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280 func GetsockoptIPv6Mreq(fd, level, opt int) (*IPv6Mreq, error) {
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281 var value IPv6Mreq
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282 vallen := _Socklen(SizeofIPv6Mreq)
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283 err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
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284 return &value, err
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285 }
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286
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287 func GetsockoptIPv6MTUInfo(fd, level, opt int) (*IPv6MTUInfo, error) {
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288 var value IPv6MTUInfo
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289 vallen := _Socklen(SizeofIPv6MTUInfo)
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290 err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
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291 return &value, err
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292 }
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293
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294 func GetsockoptICMPv6Filter(fd, level, opt int) (*ICMPv6Filter, error) {
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295 var value ICMPv6Filter
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296 vallen := _Socklen(SizeofICMPv6Filter)
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297 err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
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298 return &value, err
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299 }
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300
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301 func GetsockoptLinger(fd, level, opt int) (*Linger, error) {
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302 var linger Linger
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303 vallen := _Socklen(SizeofLinger)
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304 err := getsockopt(fd, level, opt, unsafe.Pointer(&linger), &vallen)
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305 return &linger, err
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306 }
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307
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308 func GetsockoptTimeval(fd, level, opt int) (*Timeval, error) {
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309 var tv Timeval
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310 vallen := _Socklen(unsafe.Sizeof(tv))
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311 err := getsockopt(fd, level, opt, unsafe.Pointer(&tv), &vallen)
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312 return &tv, err
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313 }
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314
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315 func GetsockoptUint64(fd, level, opt int) (value uint64, err error) {
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316 var n uint64
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317 vallen := _Socklen(8)
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318 err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen)
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319 return n, err
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320 }
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321
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322 func Recvfrom(fd int, p []byte, flags int) (n int, from Sockaddr, err error) {
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323 var rsa RawSockaddrAny
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324 var len _Socklen = SizeofSockaddrAny
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325 if n, err = recvfrom(fd, p, flags, &rsa, &len); err != nil {
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326 return
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327 }
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328 if rsa.Addr.Family != AF_UNSPEC {
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329 from, err = anyToSockaddr(fd, &rsa)
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330 }
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331 return
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332 }
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333
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334 func Recvmsg(fd int, p, oob []byte, flags int) (n, oobn int, recvflags int, from Sockaddr, err error) {
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335 var iov [1]Iovec
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336 if len(p) > 0 {
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337 iov[0].Base = &p[0]
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338 iov[0].SetLen(len(p))
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339 }
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340 var rsa RawSockaddrAny
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341 n, oobn, recvflags, err = recvmsgRaw(fd, iov[:], oob, flags, &rsa)
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342 // source address is only specified if the socket is unconnected
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343 if rsa.Addr.Family != AF_UNSPEC {
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344 from, err = anyToSockaddr(fd, &rsa)
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345 }
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346 return
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347 }
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348
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349 // RecvmsgBuffers receives a message from a socket using the recvmsg
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350 // system call. The flags are passed to recvmsg. Any non-control data
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351 // read is scattered into the buffers slices. The results are:
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352 // - n is the number of non-control data read into bufs
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353 // - oobn is the number of control data read into oob; this may be interpreted using [ParseSocketControlMessage]
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354 // - recvflags is flags returned by recvmsg
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355 // - from is the address of the sender
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356 func RecvmsgBuffers(fd int, buffers [][]byte, oob []byte, flags int) (n, oobn int, recvflags int, from Sockaddr, err error) {
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357 iov := make([]Iovec, len(buffers))
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358 for i := range buffers {
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359 if len(buffers[i]) > 0 {
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360 iov[i].Base = &buffers[i][0]
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361 iov[i].SetLen(len(buffers[i]))
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362 } else {
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363 iov[i].Base = (*byte)(unsafe.Pointer(&_zero))
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364 }
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365 }
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366 var rsa RawSockaddrAny
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367 n, oobn, recvflags, err = recvmsgRaw(fd, iov, oob, flags, &rsa)
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368 if err == nil && rsa.Addr.Family != AF_UNSPEC {
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369 from, err = anyToSockaddr(fd, &rsa)
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370 }
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371 return
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372 }
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373
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374 func Sendmsg(fd int, p, oob []byte, to Sockaddr, flags int) (err error) {
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375 _, err = SendmsgN(fd, p, oob, to, flags)
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376 return
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377 }
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378
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379 func SendmsgN(fd int, p, oob []byte, to Sockaddr, flags int) (n int, err error) {
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380 var iov [1]Iovec
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381 if len(p) > 0 {
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382 iov[0].Base = &p[0]
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383 iov[0].SetLen(len(p))
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384 }
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385 var ptr unsafe.Pointer
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386 var salen _Socklen
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387 if to != nil {
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388 ptr, salen, err = to.sockaddr()
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389 if err != nil {
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390 return 0, err
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391 }
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392 }
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393 return sendmsgN(fd, iov[:], oob, ptr, salen, flags)
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394 }
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395
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396 // SendmsgBuffers sends a message on a socket to an address using the sendmsg
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397 // system call. The flags are passed to sendmsg. Any non-control data written
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398 // is gathered from buffers. The function returns the number of bytes written
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399 // to the socket.
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400 func SendmsgBuffers(fd int, buffers [][]byte, oob []byte, to Sockaddr, flags int) (n int, err error) {
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401 iov := make([]Iovec, len(buffers))
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402 for i := range buffers {
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403 if len(buffers[i]) > 0 {
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404 iov[i].Base = &buffers[i][0]
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405 iov[i].SetLen(len(buffers[i]))
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406 } else {
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407 iov[i].Base = (*byte)(unsafe.Pointer(&_zero))
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408 }
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409 }
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410 var ptr unsafe.Pointer
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411 var salen _Socklen
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412 if to != nil {
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413 ptr, salen, err = to.sockaddr()
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414 if err != nil {
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415 return 0, err
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416 }
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417 }
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418 return sendmsgN(fd, iov, oob, ptr, salen, flags)
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419 }
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420
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421 func Send(s int, buf []byte, flags int) (err error) {
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422 return sendto(s, buf, flags, nil, 0)
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423 }
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424
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425 func Sendto(fd int, p []byte, flags int, to Sockaddr) (err error) {
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68
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426 var ptr unsafe.Pointer
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427 var salen _Socklen
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428 if to != nil {
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429 ptr, salen, err = to.sockaddr()
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430 if err != nil {
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431 return err
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432 }
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66
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433 }
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68
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434 return sendto(fd, p, flags, ptr, salen)
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66
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435 }
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436
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437 func SetsockoptByte(fd, level, opt int, value byte) (err error) {
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438 return setsockopt(fd, level, opt, unsafe.Pointer(&value), 1)
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439 }
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440
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441 func SetsockoptInt(fd, level, opt int, value int) (err error) {
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442 var n = int32(value)
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443 return setsockopt(fd, level, opt, unsafe.Pointer(&n), 4)
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444 }
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445
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446 func SetsockoptInet4Addr(fd, level, opt int, value [4]byte) (err error) {
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447 return setsockopt(fd, level, opt, unsafe.Pointer(&value[0]), 4)
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448 }
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449
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450 func SetsockoptIPMreq(fd, level, opt int, mreq *IPMreq) (err error) {
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451 return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPMreq)
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452 }
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453
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454 func SetsockoptIPv6Mreq(fd, level, opt int, mreq *IPv6Mreq) (err error) {
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455 return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPv6Mreq)
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456 }
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457
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458 func SetsockoptICMPv6Filter(fd, level, opt int, filter *ICMPv6Filter) error {
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459 return setsockopt(fd, level, opt, unsafe.Pointer(filter), SizeofICMPv6Filter)
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460 }
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461
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462 func SetsockoptLinger(fd, level, opt int, l *Linger) (err error) {
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463 return setsockopt(fd, level, opt, unsafe.Pointer(l), SizeofLinger)
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464 }
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465
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466 func SetsockoptString(fd, level, opt int, s string) (err error) {
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467 var p unsafe.Pointer
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468 if len(s) > 0 {
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469 p = unsafe.Pointer(&[]byte(s)[0])
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470 }
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471 return setsockopt(fd, level, opt, p, uintptr(len(s)))
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472 }
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473
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474 func SetsockoptTimeval(fd, level, opt int, tv *Timeval) (err error) {
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475 return setsockopt(fd, level, opt, unsafe.Pointer(tv), unsafe.Sizeof(*tv))
|
|
476 }
|
|
477
|
|
478 func SetsockoptUint64(fd, level, opt int, value uint64) (err error) {
|
|
479 return setsockopt(fd, level, opt, unsafe.Pointer(&value), 8)
|
|
480 }
|
|
481
|
|
482 func Socket(domain, typ, proto int) (fd int, err error) {
|
|
483 if domain == AF_INET6 && SocketDisableIPv6 {
|
|
484 return -1, EAFNOSUPPORT
|
|
485 }
|
|
486 fd, err = socket(domain, typ, proto)
|
|
487 return
|
|
488 }
|
|
489
|
|
490 func Socketpair(domain, typ, proto int) (fd [2]int, err error) {
|
|
491 var fdx [2]int32
|
|
492 err = socketpair(domain, typ, proto, &fdx)
|
|
493 if err == nil {
|
|
494 fd[0] = int(fdx[0])
|
|
495 fd[1] = int(fdx[1])
|
|
496 }
|
|
497 return
|
|
498 }
|
|
499
|
|
500 var ioSync int64
|
|
501
|
|
502 func CloseOnExec(fd int) { fcntl(fd, F_SETFD, FD_CLOEXEC) }
|
|
503
|
|
504 func SetNonblock(fd int, nonblocking bool) (err error) {
|
|
505 flag, err := fcntl(fd, F_GETFL, 0)
|
|
506 if err != nil {
|
|
507 return err
|
|
508 }
|
|
509 if nonblocking {
|
|
510 flag |= O_NONBLOCK
|
|
511 } else {
|
|
512 flag &= ^O_NONBLOCK
|
|
513 }
|
|
514 _, err = fcntl(fd, F_SETFL, flag)
|
|
515 return err
|
|
516 }
|
|
517
|
|
518 // Exec calls execve(2), which replaces the calling executable in the process
|
|
519 // tree. argv0 should be the full path to an executable ("/bin/ls") and the
|
|
520 // executable name should also be the first argument in argv (["ls", "-l"]).
|
|
521 // envv are the environment variables that should be passed to the new
|
|
522 // process (["USER=go", "PWD=/tmp"]).
|
|
523 func Exec(argv0 string, argv []string, envv []string) error {
|
|
524 return syscall.Exec(argv0, argv, envv)
|
|
525 }
|
|
526
|
|
527 // Lutimes sets the access and modification times tv on path. If path refers to
|
|
528 // a symlink, it is not dereferenced and the timestamps are set on the symlink.
|
|
529 // If tv is nil, the access and modification times are set to the current time.
|
|
530 // Otherwise tv must contain exactly 2 elements, with access time as the first
|
|
531 // element and modification time as the second element.
|
|
532 func Lutimes(path string, tv []Timeval) error {
|
|
533 if tv == nil {
|
|
534 return UtimesNanoAt(AT_FDCWD, path, nil, AT_SYMLINK_NOFOLLOW)
|
|
535 }
|
|
536 if len(tv) != 2 {
|
|
537 return EINVAL
|
|
538 }
|
|
539 ts := []Timespec{
|
|
540 NsecToTimespec(TimevalToNsec(tv[0])),
|
|
541 NsecToTimespec(TimevalToNsec(tv[1])),
|
|
542 }
|
|
543 return UtimesNanoAt(AT_FDCWD, path, ts, AT_SYMLINK_NOFOLLOW)
|
|
544 }
|
|
545
|
|
546 // emptyIovec reports whether there are no bytes in the slice of Iovec.
|
|
547 func emptyIovecs(iov []Iovec) bool {
|
|
548 for i := range iov {
|
|
549 if iov[i].Len > 0 {
|
|
550 return false
|
|
551 }
|
|
552 }
|
|
553 return true
|
|
554 }
|