github.com/alexis81/domosgo@v0.0.0-20191016125037-5aee90a434af/Domos/src/golang.org/x/sys/unix/syscall_unix.go (about) 1 // Copyright 2009 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 // +build darwin dragonfly freebsd linux netbsd openbsd solaris 6 7 package unix 8 9 import ( 10 "bytes" 11 "runtime" 12 "sync" 13 "syscall" 14 "unsafe" 15 ) 16 17 var ( 18 Stdin = 0 19 Stdout = 1 20 Stderr = 2 21 ) 22 23 const ( 24 darwin64Bit = runtime.GOOS == "darwin" && sizeofPtr == 8 25 dragonfly64Bit = runtime.GOOS == "dragonfly" && sizeofPtr == 8 26 netbsd32Bit = runtime.GOOS == "netbsd" && sizeofPtr == 4 27 solaris64Bit = runtime.GOOS == "solaris" && sizeofPtr == 8 28 ) 29 30 // Do the interface allocations only once for common 31 // Errno values. 32 var ( 33 errEAGAIN error = syscall.EAGAIN 34 errEINVAL error = syscall.EINVAL 35 errENOENT error = syscall.ENOENT 36 ) 37 38 // errnoErr returns common boxed Errno values, to prevent 39 // allocations at runtime. 40 func errnoErr(e syscall.Errno) error { 41 switch e { 42 case 0: 43 return nil 44 case EAGAIN: 45 return errEAGAIN 46 case EINVAL: 47 return errEINVAL 48 case ENOENT: 49 return errENOENT 50 } 51 return e 52 } 53 54 // clen returns the index of the first NULL byte in n or len(n) if n contains no NULL byte. 55 func clen(n []byte) int { 56 i := bytes.IndexByte(n, 0) 57 if i == -1 { 58 i = len(n) 59 } 60 return i 61 } 62 63 // Mmap manager, for use by operating system-specific implementations. 64 65 type mmapper struct { 66 sync.Mutex 67 active map[*byte][]byte // active mappings; key is last byte in mapping 68 mmap func(addr, length uintptr, prot, flags, fd int, offset int64) (uintptr, error) 69 munmap func(addr uintptr, length uintptr) error 70 } 71 72 func (m *mmapper) Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) { 73 if length <= 0 { 74 return nil, EINVAL 75 } 76 77 // Map the requested memory. 78 addr, errno := m.mmap(0, uintptr(length), prot, flags, fd, offset) 79 if errno != nil { 80 return nil, errno 81 } 82 83 // Slice memory layout 84 var sl = struct { 85 addr uintptr 86 len int 87 cap int 88 }{addr, length, length} 89 90 // Use unsafe to turn sl into a []byte. 91 b := *(*[]byte)(unsafe.Pointer(&sl)) 92 93 // Register mapping in m and return it. 94 p := &b[cap(b)-1] 95 m.Lock() 96 defer m.Unlock() 97 m.active[p] = b 98 return b, nil 99 } 100 101 func (m *mmapper) Munmap(data []byte) (err error) { 102 if len(data) == 0 || len(data) != cap(data) { 103 return EINVAL 104 } 105 106 // Find the base of the mapping. 107 p := &data[cap(data)-1] 108 m.Lock() 109 defer m.Unlock() 110 b := m.active[p] 111 if b == nil || &b[0] != &data[0] { 112 return EINVAL 113 } 114 115 // Unmap the memory and update m. 116 if errno := m.munmap(uintptr(unsafe.Pointer(&b[0])), uintptr(len(b))); errno != nil { 117 return errno 118 } 119 delete(m.active, p) 120 return nil 121 } 122 123 func Read(fd int, p []byte) (n int, err error) { 124 n, err = read(fd, p) 125 if raceenabled { 126 if n > 0 { 127 raceWriteRange(unsafe.Pointer(&p[0]), n) 128 } 129 if err == nil { 130 raceAcquire(unsafe.Pointer(&ioSync)) 131 } 132 } 133 return 134 } 135 136 func Write(fd int, p []byte) (n int, err error) { 137 if raceenabled { 138 raceReleaseMerge(unsafe.Pointer(&ioSync)) 139 } 140 n, err = write(fd, p) 141 if raceenabled && n > 0 { 142 raceReadRange(unsafe.Pointer(&p[0]), n) 143 } 144 return 145 } 146 147 // For testing: clients can set this flag to force 148 // creation of IPv6 sockets to return EAFNOSUPPORT. 149 var SocketDisableIPv6 bool 150 151 // Sockaddr represents a socket address. 152 type Sockaddr interface { 153 sockaddr() (ptr unsafe.Pointer, len _Socklen, err error) // lowercase; only we can define Sockaddrs 154 } 155 156 // SockaddrInet4 implements the Sockaddr interface for AF_INET type sockets. 157 type SockaddrInet4 struct { 158 Port int 159 Addr [4]byte 160 raw RawSockaddrInet4 161 } 162 163 // SockaddrInet6 implements the Sockaddr interface for AF_INET6 type sockets. 164 type SockaddrInet6 struct { 165 Port int 166 ZoneId uint32 167 Addr [16]byte 168 raw RawSockaddrInet6 169 } 170 171 // SockaddrUnix implements the Sockaddr interface for AF_UNIX type sockets. 172 type SockaddrUnix struct { 173 Name string 174 raw RawSockaddrUnix 175 } 176 177 func Bind(fd int, sa Sockaddr) (err error) { 178 ptr, n, err := sa.sockaddr() 179 if err != nil { 180 return err 181 } 182 return bind(fd, ptr, n) 183 } 184 185 func Connect(fd int, sa Sockaddr) (err error) { 186 ptr, n, err := sa.sockaddr() 187 if err != nil { 188 return err 189 } 190 return connect(fd, ptr, n) 191 } 192 193 func Getpeername(fd int) (sa Sockaddr, err error) { 194 var rsa RawSockaddrAny 195 var len _Socklen = SizeofSockaddrAny 196 if err = getpeername(fd, &rsa, &len); err != nil { 197 return 198 } 199 return anyToSockaddr(&rsa) 200 } 201 202 func GetsockoptInt(fd, level, opt int) (value int, err error) { 203 var n int32 204 vallen := _Socklen(4) 205 err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen) 206 return int(n), err 207 } 208 209 func GetsockoptLinger(fd, level, opt int) (*Linger, error) { 210 var linger Linger 211 vallen := _Socklen(SizeofLinger) 212 err := getsockopt(fd, level, opt, unsafe.Pointer(&linger), &vallen) 213 return &linger, err 214 } 215 216 func GetsockoptTimeval(fd, level, opt int) (*Timeval, error) { 217 var tv Timeval 218 vallen := _Socklen(unsafe.Sizeof(tv)) 219 err := getsockopt(fd, level, opt, unsafe.Pointer(&tv), &vallen) 220 return &tv, err 221 } 222 223 func Recvfrom(fd int, p []byte, flags int) (n int, from Sockaddr, err error) { 224 var rsa RawSockaddrAny 225 var len _Socklen = SizeofSockaddrAny 226 if n, err = recvfrom(fd, p, flags, &rsa, &len); err != nil { 227 return 228 } 229 if rsa.Addr.Family != AF_UNSPEC { 230 from, err = anyToSockaddr(&rsa) 231 } 232 return 233 } 234 235 func Sendto(fd int, p []byte, flags int, to Sockaddr) (err error) { 236 ptr, n, err := to.sockaddr() 237 if err != nil { 238 return err 239 } 240 return sendto(fd, p, flags, ptr, n) 241 } 242 243 func SetsockoptByte(fd, level, opt int, value byte) (err error) { 244 return setsockopt(fd, level, opt, unsafe.Pointer(&value), 1) 245 } 246 247 func SetsockoptInt(fd, level, opt int, value int) (err error) { 248 var n = int32(value) 249 return setsockopt(fd, level, opt, unsafe.Pointer(&n), 4) 250 } 251 252 func SetsockoptInet4Addr(fd, level, opt int, value [4]byte) (err error) { 253 return setsockopt(fd, level, opt, unsafe.Pointer(&value[0]), 4) 254 } 255 256 func SetsockoptIPMreq(fd, level, opt int, mreq *IPMreq) (err error) { 257 return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPMreq) 258 } 259 260 func SetsockoptIPv6Mreq(fd, level, opt int, mreq *IPv6Mreq) (err error) { 261 return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPv6Mreq) 262 } 263 264 func SetsockoptICMPv6Filter(fd, level, opt int, filter *ICMPv6Filter) error { 265 return setsockopt(fd, level, opt, unsafe.Pointer(filter), SizeofICMPv6Filter) 266 } 267 268 func SetsockoptLinger(fd, level, opt int, l *Linger) (err error) { 269 return setsockopt(fd, level, opt, unsafe.Pointer(l), SizeofLinger) 270 } 271 272 func SetsockoptString(fd, level, opt int, s string) (err error) { 273 return setsockopt(fd, level, opt, unsafe.Pointer(&[]byte(s)[0]), uintptr(len(s))) 274 } 275 276 func SetsockoptTimeval(fd, level, opt int, tv *Timeval) (err error) { 277 return setsockopt(fd, level, opt, unsafe.Pointer(tv), unsafe.Sizeof(*tv)) 278 } 279 280 func Socket(domain, typ, proto int) (fd int, err error) { 281 if domain == AF_INET6 && SocketDisableIPv6 { 282 return -1, EAFNOSUPPORT 283 } 284 fd, err = socket(domain, typ, proto) 285 return 286 } 287 288 func Socketpair(domain, typ, proto int) (fd [2]int, err error) { 289 var fdx [2]int32 290 err = socketpair(domain, typ, proto, &fdx) 291 if err == nil { 292 fd[0] = int(fdx[0]) 293 fd[1] = int(fdx[1]) 294 } 295 return 296 } 297 298 func Sendfile(outfd int, infd int, offset *int64, count int) (written int, err error) { 299 if raceenabled { 300 raceReleaseMerge(unsafe.Pointer(&ioSync)) 301 } 302 return sendfile(outfd, infd, offset, count) 303 } 304 305 var ioSync int64 306 307 func CloseOnExec(fd int) { fcntl(fd, F_SETFD, FD_CLOEXEC) } 308 309 func SetNonblock(fd int, nonblocking bool) (err error) { 310 flag, err := fcntl(fd, F_GETFL, 0) 311 if err != nil { 312 return err 313 } 314 if nonblocking { 315 flag |= O_NONBLOCK 316 } else { 317 flag &= ^O_NONBLOCK 318 } 319 _, err = fcntl(fd, F_SETFL, flag) 320 return err 321 } 322 323 // Exec calls execve(2), which replaces the calling executable in the process 324 // tree. argv0 should be the full path to an executable ("/bin/ls") and the 325 // executable name should also be the first argument in argv (["ls", "-l"]). 326 // envv are the environment variables that should be passed to the new 327 // process (["USER=go", "PWD=/tmp"]). 328 func Exec(argv0 string, argv []string, envv []string) error { 329 return syscall.Exec(argv0, argv, envv) 330 }