github.com/fletavendor/sys@v0.0.0-20181107165924-66b7b1311ac8/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 aix darwin dragonfly freebsd linux netbsd openbsd solaris 6 7 package unix 8 9 import ( 10 "bytes" 11 "runtime" 12 "sort" 13 "sync" 14 "syscall" 15 "unsafe" 16 ) 17 18 var ( 19 Stdin = 0 20 Stdout = 1 21 Stderr = 2 22 ) 23 24 const ( 25 darwin64Bit = runtime.GOOS == "darwin" && SizeofPtr == 8 26 dragonfly64Bit = runtime.GOOS == "dragonfly" && SizeofPtr == 8 27 netbsd32Bit = runtime.GOOS == "netbsd" && SizeofPtr == 4 28 solaris64Bit = runtime.GOOS == "solaris" && SizeofPtr == 8 29 ) 30 31 // Do the interface allocations only once for common 32 // Errno values. 33 var ( 34 errEAGAIN error = syscall.EAGAIN 35 errEINVAL error = syscall.EINVAL 36 errENOENT error = syscall.ENOENT 37 ) 38 39 // errnoErr returns common boxed Errno values, to prevent 40 // allocations at runtime. 41 func errnoErr(e syscall.Errno) error { 42 switch e { 43 case 0: 44 return nil 45 case EAGAIN: 46 return errEAGAIN 47 case EINVAL: 48 return errEINVAL 49 case ENOENT: 50 return errENOENT 51 } 52 return e 53 } 54 55 // ErrnoName returns the error name for error number e. 56 func ErrnoName(e syscall.Errno) string { 57 i := sort.Search(len(errorList), func(i int) bool { 58 return errorList[i].num >= e 59 }) 60 if i < len(errorList) && errorList[i].num == e { 61 return errorList[i].name 62 } 63 return "" 64 } 65 66 // SignalName returns the signal name for signal number s. 67 func SignalName(s syscall.Signal) string { 68 i := sort.Search(len(signalList), func(i int) bool { 69 return signalList[i].num >= s 70 }) 71 if i < len(signalList) && signalList[i].num == s { 72 return signalList[i].name 73 } 74 return "" 75 } 76 77 // clen returns the index of the first NULL byte in n or len(n) if n contains no NULL byte. 78 func clen(n []byte) int { 79 i := bytes.IndexByte(n, 0) 80 if i == -1 { 81 i = len(n) 82 } 83 return i 84 } 85 86 // Mmap manager, for use by operating system-specific implementations. 87 88 type mmapper struct { 89 sync.Mutex 90 active map[*byte][]byte // active mappings; key is last byte in mapping 91 mmap func(addr, length uintptr, prot, flags, fd int, offset int64) (uintptr, error) 92 munmap func(addr uintptr, length uintptr) error 93 } 94 95 func (m *mmapper) Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) { 96 if length <= 0 { 97 return nil, EINVAL 98 } 99 100 // Map the requested memory. 101 addr, errno := m.mmap(0, uintptr(length), prot, flags, fd, offset) 102 if errno != nil { 103 return nil, errno 104 } 105 106 // Slice memory layout 107 var sl = struct { 108 addr uintptr 109 len int 110 cap int 111 }{addr, length, length} 112 113 // Use unsafe to turn sl into a []byte. 114 b := *(*[]byte)(unsafe.Pointer(&sl)) 115 116 // Register mapping in m and return it. 117 p := &b[cap(b)-1] 118 m.Lock() 119 defer m.Unlock() 120 m.active[p] = b 121 return b, nil 122 } 123 124 func (m *mmapper) Munmap(data []byte) (err error) { 125 if len(data) == 0 || len(data) != cap(data) { 126 return EINVAL 127 } 128 129 // Find the base of the mapping. 130 p := &data[cap(data)-1] 131 m.Lock() 132 defer m.Unlock() 133 b := m.active[p] 134 if b == nil || &b[0] != &data[0] { 135 return EINVAL 136 } 137 138 // Unmap the memory and update m. 139 if errno := m.munmap(uintptr(unsafe.Pointer(&b[0])), uintptr(len(b))); errno != nil { 140 return errno 141 } 142 delete(m.active, p) 143 return nil 144 } 145 146 func Read(fd int, p []byte) (n int, err error) { 147 n, err = read(fd, p) 148 if raceenabled { 149 if n > 0 { 150 raceWriteRange(unsafe.Pointer(&p[0]), n) 151 } 152 if err == nil { 153 raceAcquire(unsafe.Pointer(&ioSync)) 154 } 155 } 156 return 157 } 158 159 func Write(fd int, p []byte) (n int, err error) { 160 if raceenabled { 161 raceReleaseMerge(unsafe.Pointer(&ioSync)) 162 } 163 n, err = write(fd, p) 164 if raceenabled && n > 0 { 165 raceReadRange(unsafe.Pointer(&p[0]), n) 166 } 167 return 168 } 169 170 // For testing: clients can set this flag to force 171 // creation of IPv6 sockets to return EAFNOSUPPORT. 172 var SocketDisableIPv6 bool 173 174 // Sockaddr represents a socket address. 175 type Sockaddr interface { 176 sockaddr() (ptr unsafe.Pointer, len _Socklen, err error) // lowercase; only we can define Sockaddrs 177 } 178 179 // SockaddrInet4 implements the Sockaddr interface for AF_INET type sockets. 180 type SockaddrInet4 struct { 181 Port int 182 Addr [4]byte 183 raw RawSockaddrInet4 184 } 185 186 // SockaddrInet6 implements the Sockaddr interface for AF_INET6 type sockets. 187 type SockaddrInet6 struct { 188 Port int 189 ZoneId uint32 190 Addr [16]byte 191 raw RawSockaddrInet6 192 } 193 194 // SockaddrUnix implements the Sockaddr interface for AF_UNIX type sockets. 195 type SockaddrUnix struct { 196 Name string 197 raw RawSockaddrUnix 198 } 199 200 func Bind(fd int, sa Sockaddr) (err error) { 201 ptr, n, err := sa.sockaddr() 202 if err != nil { 203 return err 204 } 205 return bind(fd, ptr, n) 206 } 207 208 func Connect(fd int, sa Sockaddr) (err error) { 209 ptr, n, err := sa.sockaddr() 210 if err != nil { 211 return err 212 } 213 return connect(fd, ptr, n) 214 } 215 216 func Getpeername(fd int) (sa Sockaddr, err error) { 217 var rsa RawSockaddrAny 218 var len _Socklen = SizeofSockaddrAny 219 if err = getpeername(fd, &rsa, &len); err != nil { 220 return 221 } 222 return anyToSockaddr(fd, &rsa) 223 } 224 225 func GetsockoptByte(fd, level, opt int) (value byte, err error) { 226 var n byte 227 vallen := _Socklen(1) 228 err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen) 229 return n, err 230 } 231 232 func GetsockoptInt(fd, level, opt int) (value int, err error) { 233 var n int32 234 vallen := _Socklen(4) 235 err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen) 236 return int(n), err 237 } 238 239 func GetsockoptInet4Addr(fd, level, opt int) (value [4]byte, err error) { 240 vallen := _Socklen(4) 241 err = getsockopt(fd, level, opt, unsafe.Pointer(&value[0]), &vallen) 242 return value, err 243 } 244 245 func GetsockoptIPMreq(fd, level, opt int) (*IPMreq, error) { 246 var value IPMreq 247 vallen := _Socklen(SizeofIPMreq) 248 err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) 249 return &value, err 250 } 251 252 func GetsockoptIPv6Mreq(fd, level, opt int) (*IPv6Mreq, error) { 253 var value IPv6Mreq 254 vallen := _Socklen(SizeofIPv6Mreq) 255 err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) 256 return &value, err 257 } 258 259 func GetsockoptIPv6MTUInfo(fd, level, opt int) (*IPv6MTUInfo, error) { 260 var value IPv6MTUInfo 261 vallen := _Socklen(SizeofIPv6MTUInfo) 262 err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) 263 return &value, err 264 } 265 266 func GetsockoptICMPv6Filter(fd, level, opt int) (*ICMPv6Filter, error) { 267 var value ICMPv6Filter 268 vallen := _Socklen(SizeofICMPv6Filter) 269 err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) 270 return &value, err 271 } 272 273 func GetsockoptLinger(fd, level, opt int) (*Linger, error) { 274 var linger Linger 275 vallen := _Socklen(SizeofLinger) 276 err := getsockopt(fd, level, opt, unsafe.Pointer(&linger), &vallen) 277 return &linger, err 278 } 279 280 func GetsockoptTimeval(fd, level, opt int) (*Timeval, error) { 281 var tv Timeval 282 vallen := _Socklen(unsafe.Sizeof(tv)) 283 err := getsockopt(fd, level, opt, unsafe.Pointer(&tv), &vallen) 284 return &tv, err 285 } 286 287 func Recvfrom(fd int, p []byte, flags int) (n int, from Sockaddr, err error) { 288 var rsa RawSockaddrAny 289 var len _Socklen = SizeofSockaddrAny 290 if n, err = recvfrom(fd, p, flags, &rsa, &len); err != nil { 291 return 292 } 293 if rsa.Addr.Family != AF_UNSPEC { 294 from, err = anyToSockaddr(fd, &rsa) 295 } 296 return 297 } 298 299 func Sendto(fd int, p []byte, flags int, to Sockaddr) (err error) { 300 ptr, n, err := to.sockaddr() 301 if err != nil { 302 return err 303 } 304 return sendto(fd, p, flags, ptr, n) 305 } 306 307 func SetsockoptByte(fd, level, opt int, value byte) (err error) { 308 return setsockopt(fd, level, opt, unsafe.Pointer(&value), 1) 309 } 310 311 func SetsockoptInt(fd, level, opt int, value int) (err error) { 312 var n = int32(value) 313 return setsockopt(fd, level, opt, unsafe.Pointer(&n), 4) 314 } 315 316 func SetsockoptInet4Addr(fd, level, opt int, value [4]byte) (err error) { 317 return setsockopt(fd, level, opt, unsafe.Pointer(&value[0]), 4) 318 } 319 320 func SetsockoptIPMreq(fd, level, opt int, mreq *IPMreq) (err error) { 321 return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPMreq) 322 } 323 324 func SetsockoptIPv6Mreq(fd, level, opt int, mreq *IPv6Mreq) (err error) { 325 return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPv6Mreq) 326 } 327 328 func SetsockoptICMPv6Filter(fd, level, opt int, filter *ICMPv6Filter) error { 329 return setsockopt(fd, level, opt, unsafe.Pointer(filter), SizeofICMPv6Filter) 330 } 331 332 func SetsockoptLinger(fd, level, opt int, l *Linger) (err error) { 333 return setsockopt(fd, level, opt, unsafe.Pointer(l), SizeofLinger) 334 } 335 336 func SetsockoptString(fd, level, opt int, s string) (err error) { 337 return setsockopt(fd, level, opt, unsafe.Pointer(&[]byte(s)[0]), uintptr(len(s))) 338 } 339 340 func SetsockoptTimeval(fd, level, opt int, tv *Timeval) (err error) { 341 return setsockopt(fd, level, opt, unsafe.Pointer(tv), unsafe.Sizeof(*tv)) 342 } 343 344 func Socket(domain, typ, proto int) (fd int, err error) { 345 if domain == AF_INET6 && SocketDisableIPv6 { 346 return -1, EAFNOSUPPORT 347 } 348 fd, err = socket(domain, typ, proto) 349 return 350 } 351 352 func Socketpair(domain, typ, proto int) (fd [2]int, err error) { 353 var fdx [2]int32 354 err = socketpair(domain, typ, proto, &fdx) 355 if err == nil { 356 fd[0] = int(fdx[0]) 357 fd[1] = int(fdx[1]) 358 } 359 return 360 } 361 362 func Sendfile(outfd int, infd int, offset *int64, count int) (written int, err error) { 363 if raceenabled { 364 raceReleaseMerge(unsafe.Pointer(&ioSync)) 365 } 366 return sendfile(outfd, infd, offset, count) 367 } 368 369 var ioSync int64 370 371 func CloseOnExec(fd int) { fcntl(fd, F_SETFD, FD_CLOEXEC) } 372 373 func SetNonblock(fd int, nonblocking bool) (err error) { 374 flag, err := fcntl(fd, F_GETFL, 0) 375 if err != nil { 376 return err 377 } 378 if nonblocking { 379 flag |= O_NONBLOCK 380 } else { 381 flag &= ^O_NONBLOCK 382 } 383 _, err = fcntl(fd, F_SETFL, flag) 384 return err 385 } 386 387 // Exec calls execve(2), which replaces the calling executable in the process 388 // tree. argv0 should be the full path to an executable ("/bin/ls") and the 389 // executable name should also be the first argument in argv (["ls", "-l"]). 390 // envv are the environment variables that should be passed to the new 391 // process (["USER=go", "PWD=/tmp"]). 392 func Exec(argv0 string, argv []string, envv []string) error { 393 return syscall.Exec(argv0, argv, envv) 394 }