David K. Bainbridge | 215e024 | 2017-09-05 23:18:24 -0700 | [diff] [blame] | 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 | "runtime" |
| 11 | "sync" |
| 12 | "syscall" |
| 13 | "unsafe" |
| 14 | ) |
| 15 | |
| 16 | var ( |
| 17 | Stdin = 0 |
| 18 | Stdout = 1 |
| 19 | Stderr = 2 |
| 20 | ) |
| 21 | |
| 22 | const ( |
| 23 | darwin64Bit = runtime.GOOS == "darwin" && sizeofPtr == 8 |
| 24 | dragonfly64Bit = runtime.GOOS == "dragonfly" && sizeofPtr == 8 |
| 25 | netbsd32Bit = runtime.GOOS == "netbsd" && sizeofPtr == 4 |
| 26 | solaris64Bit = runtime.GOOS == "solaris" && sizeofPtr == 8 |
| 27 | ) |
| 28 | |
| 29 | // Do the interface allocations only once for common |
| 30 | // Errno values. |
| 31 | var ( |
| 32 | errEAGAIN error = syscall.EAGAIN |
| 33 | errEINVAL error = syscall.EINVAL |
| 34 | errENOENT error = syscall.ENOENT |
| 35 | ) |
| 36 | |
| 37 | // errnoErr returns common boxed Errno values, to prevent |
| 38 | // allocations at runtime. |
| 39 | func errnoErr(e syscall.Errno) error { |
| 40 | switch e { |
| 41 | case 0: |
| 42 | return nil |
| 43 | case EAGAIN: |
| 44 | return errEAGAIN |
| 45 | case EINVAL: |
| 46 | return errEINVAL |
| 47 | case ENOENT: |
| 48 | return errENOENT |
| 49 | } |
| 50 | return e |
| 51 | } |
| 52 | |
| 53 | // Mmap manager, for use by operating system-specific implementations. |
| 54 | |
| 55 | type mmapper struct { |
| 56 | sync.Mutex |
| 57 | active map[*byte][]byte // active mappings; key is last byte in mapping |
| 58 | mmap func(addr, length uintptr, prot, flags, fd int, offset int64) (uintptr, error) |
| 59 | munmap func(addr uintptr, length uintptr) error |
| 60 | } |
| 61 | |
| 62 | func (m *mmapper) Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) { |
| 63 | if length <= 0 { |
| 64 | return nil, EINVAL |
| 65 | } |
| 66 | |
| 67 | // Map the requested memory. |
| 68 | addr, errno := m.mmap(0, uintptr(length), prot, flags, fd, offset) |
| 69 | if errno != nil { |
| 70 | return nil, errno |
| 71 | } |
| 72 | |
| 73 | // Slice memory layout |
| 74 | var sl = struct { |
| 75 | addr uintptr |
| 76 | len int |
| 77 | cap int |
| 78 | }{addr, length, length} |
| 79 | |
| 80 | // Use unsafe to turn sl into a []byte. |
| 81 | b := *(*[]byte)(unsafe.Pointer(&sl)) |
| 82 | |
| 83 | // Register mapping in m and return it. |
| 84 | p := &b[cap(b)-1] |
| 85 | m.Lock() |
| 86 | defer m.Unlock() |
| 87 | m.active[p] = b |
| 88 | return b, nil |
| 89 | } |
| 90 | |
| 91 | func (m *mmapper) Munmap(data []byte) (err error) { |
| 92 | if len(data) == 0 || len(data) != cap(data) { |
| 93 | return EINVAL |
| 94 | } |
| 95 | |
| 96 | // Find the base of the mapping. |
| 97 | p := &data[cap(data)-1] |
| 98 | m.Lock() |
| 99 | defer m.Unlock() |
| 100 | b := m.active[p] |
| 101 | if b == nil || &b[0] != &data[0] { |
| 102 | return EINVAL |
| 103 | } |
| 104 | |
| 105 | // Unmap the memory and update m. |
| 106 | if errno := m.munmap(uintptr(unsafe.Pointer(&b[0])), uintptr(len(b))); errno != nil { |
| 107 | return errno |
| 108 | } |
| 109 | delete(m.active, p) |
| 110 | return nil |
| 111 | } |
| 112 | |
| 113 | func Read(fd int, p []byte) (n int, err error) { |
| 114 | n, err = read(fd, p) |
| 115 | if raceenabled { |
| 116 | if n > 0 { |
| 117 | raceWriteRange(unsafe.Pointer(&p[0]), n) |
| 118 | } |
| 119 | if err == nil { |
| 120 | raceAcquire(unsafe.Pointer(&ioSync)) |
| 121 | } |
| 122 | } |
| 123 | return |
| 124 | } |
| 125 | |
| 126 | func Write(fd int, p []byte) (n int, err error) { |
| 127 | if raceenabled { |
| 128 | raceReleaseMerge(unsafe.Pointer(&ioSync)) |
| 129 | } |
| 130 | n, err = write(fd, p) |
| 131 | if raceenabled && n > 0 { |
| 132 | raceReadRange(unsafe.Pointer(&p[0]), n) |
| 133 | } |
| 134 | return |
| 135 | } |
| 136 | |
| 137 | // For testing: clients can set this flag to force |
| 138 | // creation of IPv6 sockets to return EAFNOSUPPORT. |
| 139 | var SocketDisableIPv6 bool |
| 140 | |
| 141 | type Sockaddr interface { |
| 142 | sockaddr() (ptr unsafe.Pointer, len _Socklen, err error) // lowercase; only we can define Sockaddrs |
| 143 | } |
| 144 | |
| 145 | type SockaddrInet4 struct { |
| 146 | Port int |
| 147 | Addr [4]byte |
| 148 | raw RawSockaddrInet4 |
| 149 | } |
| 150 | |
| 151 | type SockaddrInet6 struct { |
| 152 | Port int |
| 153 | ZoneId uint32 |
| 154 | Addr [16]byte |
| 155 | raw RawSockaddrInet6 |
| 156 | } |
| 157 | |
| 158 | type SockaddrUnix struct { |
| 159 | Name string |
| 160 | raw RawSockaddrUnix |
| 161 | } |
| 162 | |
| 163 | func Bind(fd int, sa Sockaddr) (err error) { |
| 164 | ptr, n, err := sa.sockaddr() |
| 165 | if err != nil { |
| 166 | return err |
| 167 | } |
| 168 | return bind(fd, ptr, n) |
| 169 | } |
| 170 | |
| 171 | func Connect(fd int, sa Sockaddr) (err error) { |
| 172 | ptr, n, err := sa.sockaddr() |
| 173 | if err != nil { |
| 174 | return err |
| 175 | } |
| 176 | return connect(fd, ptr, n) |
| 177 | } |
| 178 | |
| 179 | func Getpeername(fd int) (sa Sockaddr, err error) { |
| 180 | var rsa RawSockaddrAny |
| 181 | var len _Socklen = SizeofSockaddrAny |
| 182 | if err = getpeername(fd, &rsa, &len); err != nil { |
| 183 | return |
| 184 | } |
| 185 | return anyToSockaddr(&rsa) |
| 186 | } |
| 187 | |
| 188 | func GetsockoptInt(fd, level, opt int) (value int, err error) { |
| 189 | var n int32 |
| 190 | vallen := _Socklen(4) |
| 191 | err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen) |
| 192 | return int(n), err |
| 193 | } |
| 194 | |
| 195 | func Recvfrom(fd int, p []byte, flags int) (n int, from Sockaddr, err error) { |
| 196 | var rsa RawSockaddrAny |
| 197 | var len _Socklen = SizeofSockaddrAny |
| 198 | if n, err = recvfrom(fd, p, flags, &rsa, &len); err != nil { |
| 199 | return |
| 200 | } |
| 201 | if rsa.Addr.Family != AF_UNSPEC { |
| 202 | from, err = anyToSockaddr(&rsa) |
| 203 | } |
| 204 | return |
| 205 | } |
| 206 | |
| 207 | func Sendto(fd int, p []byte, flags int, to Sockaddr) (err error) { |
| 208 | ptr, n, err := to.sockaddr() |
| 209 | if err != nil { |
| 210 | return err |
| 211 | } |
| 212 | return sendto(fd, p, flags, ptr, n) |
| 213 | } |
| 214 | |
| 215 | func SetsockoptByte(fd, level, opt int, value byte) (err error) { |
| 216 | return setsockopt(fd, level, opt, unsafe.Pointer(&value), 1) |
| 217 | } |
| 218 | |
| 219 | func SetsockoptInt(fd, level, opt int, value int) (err error) { |
| 220 | var n = int32(value) |
| 221 | return setsockopt(fd, level, opt, unsafe.Pointer(&n), 4) |
| 222 | } |
| 223 | |
| 224 | func SetsockoptInet4Addr(fd, level, opt int, value [4]byte) (err error) { |
| 225 | return setsockopt(fd, level, opt, unsafe.Pointer(&value[0]), 4) |
| 226 | } |
| 227 | |
| 228 | func SetsockoptIPMreq(fd, level, opt int, mreq *IPMreq) (err error) { |
| 229 | return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPMreq) |
| 230 | } |
| 231 | |
| 232 | func SetsockoptIPv6Mreq(fd, level, opt int, mreq *IPv6Mreq) (err error) { |
| 233 | return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPv6Mreq) |
| 234 | } |
| 235 | |
| 236 | func SetsockoptICMPv6Filter(fd, level, opt int, filter *ICMPv6Filter) error { |
| 237 | return setsockopt(fd, level, opt, unsafe.Pointer(filter), SizeofICMPv6Filter) |
| 238 | } |
| 239 | |
| 240 | func SetsockoptLinger(fd, level, opt int, l *Linger) (err error) { |
| 241 | return setsockopt(fd, level, opt, unsafe.Pointer(l), SizeofLinger) |
| 242 | } |
| 243 | |
| 244 | func SetsockoptString(fd, level, opt int, s string) (err error) { |
| 245 | return setsockopt(fd, level, opt, unsafe.Pointer(&[]byte(s)[0]), uintptr(len(s))) |
| 246 | } |
| 247 | |
| 248 | func SetsockoptTimeval(fd, level, opt int, tv *Timeval) (err error) { |
| 249 | return setsockopt(fd, level, opt, unsafe.Pointer(tv), unsafe.Sizeof(*tv)) |
| 250 | } |
| 251 | |
| 252 | func Socket(domain, typ, proto int) (fd int, err error) { |
| 253 | if domain == AF_INET6 && SocketDisableIPv6 { |
| 254 | return -1, EAFNOSUPPORT |
| 255 | } |
| 256 | fd, err = socket(domain, typ, proto) |
| 257 | return |
| 258 | } |
| 259 | |
| 260 | func Socketpair(domain, typ, proto int) (fd [2]int, err error) { |
| 261 | var fdx [2]int32 |
| 262 | err = socketpair(domain, typ, proto, &fdx) |
| 263 | if err == nil { |
| 264 | fd[0] = int(fdx[0]) |
| 265 | fd[1] = int(fdx[1]) |
| 266 | } |
| 267 | return |
| 268 | } |
| 269 | |
| 270 | func Sendfile(outfd int, infd int, offset *int64, count int) (written int, err error) { |
| 271 | if raceenabled { |
| 272 | raceReleaseMerge(unsafe.Pointer(&ioSync)) |
| 273 | } |
| 274 | return sendfile(outfd, infd, offset, count) |
| 275 | } |
| 276 | |
| 277 | var ioSync int64 |
| 278 | |
| 279 | func CloseOnExec(fd int) { fcntl(fd, F_SETFD, FD_CLOEXEC) } |
| 280 | |
| 281 | func SetNonblock(fd int, nonblocking bool) (err error) { |
| 282 | flag, err := fcntl(fd, F_GETFL, 0) |
| 283 | if err != nil { |
| 284 | return err |
| 285 | } |
| 286 | if nonblocking { |
| 287 | flag |= O_NONBLOCK |
| 288 | } else { |
| 289 | flag &= ^O_NONBLOCK |
| 290 | } |
| 291 | _, err = fcntl(fd, F_SETFL, flag) |
| 292 | return err |
| 293 | } |