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 7package unix 8 9import ( 10 "bytes" 11 "runtime" 12 "sync" 13 "syscall" 14 "unsafe" 15) 16 17var ( 18 Stdin = 0 19 Stdout = 1 20 Stderr = 2 21) 22 23const ( 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. 32var ( 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. 40func 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. 55func 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 65type 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 72func (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 101func (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 123func 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 136func 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. 149var SocketDisableIPv6 bool 150 151// Sockaddr represents a socket address. 152type 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. 157type 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. 164type 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. 172type SockaddrUnix struct { 173 Name string 174 raw RawSockaddrUnix 175} 176 177func 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 185func 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 193func 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 202func 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 209func Recvfrom(fd int, p []byte, flags int) (n int, from Sockaddr, err error) { 210 var rsa RawSockaddrAny 211 var len _Socklen = SizeofSockaddrAny 212 if n, err = recvfrom(fd, p, flags, &rsa, &len); err != nil { 213 return 214 } 215 if rsa.Addr.Family != AF_UNSPEC { 216 from, err = anyToSockaddr(&rsa) 217 } 218 return 219} 220 221func Sendto(fd int, p []byte, flags int, to Sockaddr) (err error) { 222 ptr, n, err := to.sockaddr() 223 if err != nil { 224 return err 225 } 226 return sendto(fd, p, flags, ptr, n) 227} 228 229func SetsockoptByte(fd, level, opt int, value byte) (err error) { 230 return setsockopt(fd, level, opt, unsafe.Pointer(&value), 1) 231} 232 233func SetsockoptInt(fd, level, opt int, value int) (err error) { 234 var n = int32(value) 235 return setsockopt(fd, level, opt, unsafe.Pointer(&n), 4) 236} 237 238func SetsockoptInet4Addr(fd, level, opt int, value [4]byte) (err error) { 239 return setsockopt(fd, level, opt, unsafe.Pointer(&value[0]), 4) 240} 241 242func SetsockoptIPMreq(fd, level, opt int, mreq *IPMreq) (err error) { 243 return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPMreq) 244} 245 246func SetsockoptIPv6Mreq(fd, level, opt int, mreq *IPv6Mreq) (err error) { 247 return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPv6Mreq) 248} 249 250func SetsockoptICMPv6Filter(fd, level, opt int, filter *ICMPv6Filter) error { 251 return setsockopt(fd, level, opt, unsafe.Pointer(filter), SizeofICMPv6Filter) 252} 253 254func SetsockoptLinger(fd, level, opt int, l *Linger) (err error) { 255 return setsockopt(fd, level, opt, unsafe.Pointer(l), SizeofLinger) 256} 257 258func SetsockoptString(fd, level, opt int, s string) (err error) { 259 return setsockopt(fd, level, opt, unsafe.Pointer(&[]byte(s)[0]), uintptr(len(s))) 260} 261 262func SetsockoptTimeval(fd, level, opt int, tv *Timeval) (err error) { 263 return setsockopt(fd, level, opt, unsafe.Pointer(tv), unsafe.Sizeof(*tv)) 264} 265 266func Socket(domain, typ, proto int) (fd int, err error) { 267 if domain == AF_INET6 && SocketDisableIPv6 { 268 return -1, EAFNOSUPPORT 269 } 270 fd, err = socket(domain, typ, proto) 271 return 272} 273 274func Socketpair(domain, typ, proto int) (fd [2]int, err error) { 275 var fdx [2]int32 276 err = socketpair(domain, typ, proto, &fdx) 277 if err == nil { 278 fd[0] = int(fdx[0]) 279 fd[1] = int(fdx[1]) 280 } 281 return 282} 283 284func Sendfile(outfd int, infd int, offset *int64, count int) (written int, err error) { 285 if raceenabled { 286 raceReleaseMerge(unsafe.Pointer(&ioSync)) 287 } 288 return sendfile(outfd, infd, offset, count) 289} 290 291var ioSync int64 292 293func CloseOnExec(fd int) { fcntl(fd, F_SETFD, FD_CLOEXEC) } 294 295func SetNonblock(fd int, nonblocking bool) (err error) { 296 flag, err := fcntl(fd, F_GETFL, 0) 297 if err != nil { 298 return err 299 } 300 if nonblocking { 301 flag |= O_NONBLOCK 302 } else { 303 flag &= ^O_NONBLOCK 304 } 305 _, err = fcntl(fd, F_SETFL, flag) 306 return err 307} 308 309// Exec calls execve(2), which replaces the calling executable in the process 310// tree. argv0 should be the full path to an executable ("/bin/ls") and the 311// executable name should also be the first argument in argv (["ls", "-l"]). 312// envv are the environment variables that should be passed to the new 313// process (["USER=go", "PWD=/tmp"]). 314func Exec(argv0 string, argv []string, envv []string) error { 315 return syscall.Exec(argv0, argv, envv) 316} 317