| // Copyright 2009 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| //go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris |
| // +build aix darwin dragonfly freebsd linux netbsd openbsd solaris |
| |
| package unix |
| |
| import ( |
| "bytes" |
| "sort" |
| "sync" |
| "syscall" |
| "unsafe" |
| ) |
| |
| var ( |
| Stdin = 0 |
| Stdout = 1 |
| Stderr = 2 |
| ) |
| |
| // Do the interface allocations only once for common |
| // Errno values. |
| var ( |
| errEAGAIN error = syscall.EAGAIN |
| errEINVAL error = syscall.EINVAL |
| errENOENT error = syscall.ENOENT |
| ) |
| |
| var ( |
| signalNameMapOnce sync.Once |
| signalNameMap map[string]syscall.Signal |
| ) |
| |
| // errnoErr returns common boxed Errno values, to prevent |
| // allocations at runtime. |
| func errnoErr(e syscall.Errno) error { |
| switch e { |
| case 0: |
| return nil |
| case EAGAIN: |
| return errEAGAIN |
| case EINVAL: |
| return errEINVAL |
| case ENOENT: |
| return errENOENT |
| } |
| return e |
| } |
| |
| // ErrnoName returns the error name for error number e. |
| func ErrnoName(e syscall.Errno) string { |
| i := sort.Search(len(errorList), func(i int) bool { |
| return errorList[i].num >= e |
| }) |
| if i < len(errorList) && errorList[i].num == e { |
| return errorList[i].name |
| } |
| return "" |
| } |
| |
| // SignalName returns the signal name for signal number s. |
| func SignalName(s syscall.Signal) string { |
| i := sort.Search(len(signalList), func(i int) bool { |
| return signalList[i].num >= s |
| }) |
| if i < len(signalList) && signalList[i].num == s { |
| return signalList[i].name |
| } |
| return "" |
| } |
| |
| // SignalNum returns the syscall.Signal for signal named s, |
| // or 0 if a signal with such name is not found. |
| // The signal name should start with "SIG". |
| func SignalNum(s string) syscall.Signal { |
| signalNameMapOnce.Do(func() { |
| signalNameMap = make(map[string]syscall.Signal, len(signalList)) |
| for _, signal := range signalList { |
| signalNameMap[signal.name] = signal.num |
| } |
| }) |
| return signalNameMap[s] |
| } |
| |
| // clen returns the index of the first NULL byte in n or len(n) if n contains no NULL byte. |
| func clen(n []byte) int { |
| i := bytes.IndexByte(n, 0) |
| if i == -1 { |
| i = len(n) |
| } |
| return i |
| } |
| |
| // Mmap manager, for use by operating system-specific implementations. |
| |
| type mmapper struct { |
| sync.Mutex |
| active map[*byte][]byte // active mappings; key is last byte in mapping |
| mmap func(addr, length uintptr, prot, flags, fd int, offset int64) (uintptr, error) |
| munmap func(addr uintptr, length uintptr) error |
| } |
| |
| func (m *mmapper) Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) { |
| if length <= 0 { |
| return nil, EINVAL |
| } |
| |
| // Map the requested memory. |
| addr, errno := m.mmap(0, uintptr(length), prot, flags, fd, offset) |
| if errno != nil { |
| return nil, errno |
| } |
| |
| // Use unsafe to convert addr into a []byte. |
| b := unsafe.Slice((*byte)(unsafe.Pointer(addr)), length) |
| |
| // Register mapping in m and return it. |
| p := &b[cap(b)-1] |
| m.Lock() |
| defer m.Unlock() |
| m.active[p] = b |
| return b, nil |
| } |
| |
| func (m *mmapper) Munmap(data []byte) (err error) { |
| if len(data) == 0 || len(data) != cap(data) { |
| return EINVAL |
| } |
| |
| // Find the base of the mapping. |
| p := &data[cap(data)-1] |
| m.Lock() |
| defer m.Unlock() |
| b := m.active[p] |
| if b == nil || &b[0] != &data[0] { |
| return EINVAL |
| } |
| |
| // Unmap the memory and update m. |
| if errno := m.munmap(uintptr(unsafe.Pointer(&b[0])), uintptr(len(b))); errno != nil { |
| return errno |
| } |
| delete(m.active, p) |
| return nil |
| } |
| |
| func Read(fd int, p []byte) (n int, err error) { |
| n, err = read(fd, p) |
| if raceenabled { |
| if n > 0 { |
| raceWriteRange(unsafe.Pointer(&p[0]), n) |
| } |
| if err == nil { |
| raceAcquire(unsafe.Pointer(&ioSync)) |
| } |
| } |
| return |
| } |
| |
| func Write(fd int, p []byte) (n int, err error) { |
| if raceenabled { |
| raceReleaseMerge(unsafe.Pointer(&ioSync)) |
| } |
| n, err = write(fd, p) |
| if raceenabled && n > 0 { |
| raceReadRange(unsafe.Pointer(&p[0]), n) |
| } |
| return |
| } |
| |
| func Pread(fd int, p []byte, offset int64) (n int, err error) { |
| n, err = pread(fd, p, offset) |
| if raceenabled { |
| if n > 0 { |
| raceWriteRange(unsafe.Pointer(&p[0]), n) |
| } |
| if err == nil { |
| raceAcquire(unsafe.Pointer(&ioSync)) |
| } |
| } |
| return |
| } |
| |
| func Pwrite(fd int, p []byte, offset int64) (n int, err error) { |
| if raceenabled { |
| raceReleaseMerge(unsafe.Pointer(&ioSync)) |
| } |
| n, err = pwrite(fd, p, offset) |
| if raceenabled && n > 0 { |
| raceReadRange(unsafe.Pointer(&p[0]), n) |
| } |
| return |
| } |
| |
| // For testing: clients can set this flag to force |
| // creation of IPv6 sockets to return EAFNOSUPPORT. |
| var SocketDisableIPv6 bool |
| |
| // Sockaddr represents a socket address. |
| type Sockaddr interface { |
| sockaddr() (ptr unsafe.Pointer, len _Socklen, err error) // lowercase; only we can define Sockaddrs |
| } |
| |
| // SockaddrInet4 implements the Sockaddr interface for AF_INET type sockets. |
| type SockaddrInet4 struct { |
| Port int |
| Addr [4]byte |
| raw RawSockaddrInet4 |
| } |
| |
| // SockaddrInet6 implements the Sockaddr interface for AF_INET6 type sockets. |
| type SockaddrInet6 struct { |
| Port int |
| ZoneId uint32 |
| Addr [16]byte |
| raw RawSockaddrInet6 |
| } |
| |
| // SockaddrUnix implements the Sockaddr interface for AF_UNIX type sockets. |
| type SockaddrUnix struct { |
| Name string |
| raw RawSockaddrUnix |
| } |
| |
| func Bind(fd int, sa Sockaddr) (err error) { |
| ptr, n, err := sa.sockaddr() |
| if err != nil { |
| return err |
| } |
| return bind(fd, ptr, n) |
| } |
| |
| func Connect(fd int, sa Sockaddr) (err error) { |
| ptr, n, err := sa.sockaddr() |
| if err != nil { |
| return err |
| } |
| return connect(fd, ptr, n) |
| } |
| |
| func Getpeername(fd int) (sa Sockaddr, err error) { |
| var rsa RawSockaddrAny |
| var len _Socklen = SizeofSockaddrAny |
| if err = getpeername(fd, &rsa, &len); err != nil { |
| return |
| } |
| return anyToSockaddr(fd, &rsa) |
| } |
| |
| func GetsockoptByte(fd, level, opt int) (value byte, err error) { |
| var n byte |
| vallen := _Socklen(1) |
| err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen) |
| return n, err |
| } |
| |
| func GetsockoptInt(fd, level, opt int) (value int, err error) { |
| var n int32 |
| vallen := _Socklen(4) |
| err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen) |
| return int(n), err |
| } |
| |
| func GetsockoptInet4Addr(fd, level, opt int) (value [4]byte, err error) { |
| vallen := _Socklen(4) |
| err = getsockopt(fd, level, opt, unsafe.Pointer(&value[0]), &vallen) |
| return value, err |
| } |
| |
| func GetsockoptIPMreq(fd, level, opt int) (*IPMreq, error) { |
| var value IPMreq |
| vallen := _Socklen(SizeofIPMreq) |
| err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) |
| return &value, err |
| } |
| |
| func GetsockoptIPv6Mreq(fd, level, opt int) (*IPv6Mreq, error) { |
| var value IPv6Mreq |
| vallen := _Socklen(SizeofIPv6Mreq) |
| err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) |
| return &value, err |
| } |
| |
| func GetsockoptIPv6MTUInfo(fd, level, opt int) (*IPv6MTUInfo, error) { |
| var value IPv6MTUInfo |
| vallen := _Socklen(SizeofIPv6MTUInfo) |
| err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) |
| return &value, err |
| } |
| |
| func GetsockoptICMPv6Filter(fd, level, opt int) (*ICMPv6Filter, error) { |
| var value ICMPv6Filter |
| vallen := _Socklen(SizeofICMPv6Filter) |
| err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) |
| return &value, err |
| } |
| |
| func GetsockoptLinger(fd, level, opt int) (*Linger, error) { |
| var linger Linger |
| vallen := _Socklen(SizeofLinger) |
| err := getsockopt(fd, level, opt, unsafe.Pointer(&linger), &vallen) |
| return &linger, err |
| } |
| |
| func GetsockoptTimeval(fd, level, opt int) (*Timeval, error) { |
| var tv Timeval |
| vallen := _Socklen(unsafe.Sizeof(tv)) |
| err := getsockopt(fd, level, opt, unsafe.Pointer(&tv), &vallen) |
| return &tv, err |
| } |
| |
| func GetsockoptUint64(fd, level, opt int) (value uint64, err error) { |
| var n uint64 |
| vallen := _Socklen(8) |
| err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen) |
| return n, err |
| } |
| |
| func Recvfrom(fd int, p []byte, flags int) (n int, from Sockaddr, err error) { |
| var rsa RawSockaddrAny |
| var len _Socklen = SizeofSockaddrAny |
| if n, err = recvfrom(fd, p, flags, &rsa, &len); err != nil { |
| return |
| } |
| if rsa.Addr.Family != AF_UNSPEC { |
| from, err = anyToSockaddr(fd, &rsa) |
| } |
| return |
| } |
| |
| // Recvmsg receives a message from a socket using the recvmsg system call. The |
| // received non-control data will be written to p, and any "out of band" |
| // control data will be written to oob. The flags are passed to recvmsg. |
| // |
| // The results are: |
| // - n is the number of non-control data bytes read into p |
| // - oobn is the number of control data bytes read into oob; this may be interpreted using [ParseSocketControlMessage] |
| // - recvflags is flags returned by recvmsg |
| // - from is the address of the sender |
| // |
| // If the underlying socket type is not SOCK_DGRAM, a received message |
| // containing oob data and a single '\0' of non-control data is treated as if |
| // the message contained only control data, i.e. n will be zero on return. |
| func Recvmsg(fd int, p, oob []byte, flags int) (n, oobn int, recvflags int, from Sockaddr, err error) { |
| var iov [1]Iovec |
| if len(p) > 0 { |
| iov[0].Base = &p[0] |
| iov[0].SetLen(len(p)) |
| } |
| var rsa RawSockaddrAny |
| n, oobn, recvflags, err = recvmsgRaw(fd, iov[:], oob, flags, &rsa) |
| // source address is only specified if the socket is unconnected |
| if rsa.Addr.Family != AF_UNSPEC { |
| from, err = anyToSockaddr(fd, &rsa) |
| } |
| return |
| } |
| |
| // RecvmsgBuffers receives a message from a socket using the recvmsg system |
| // call. This function is equivalent to Recvmsg, but non-control data read is |
| // scattered into the buffers slices. |
| func RecvmsgBuffers(fd int, buffers [][]byte, oob []byte, flags int) (n, oobn int, recvflags int, from Sockaddr, err error) { |
| iov := make([]Iovec, len(buffers)) |
| for i := range buffers { |
| if len(buffers[i]) > 0 { |
| iov[i].Base = &buffers[i][0] |
| iov[i].SetLen(len(buffers[i])) |
| } else { |
| iov[i].Base = (*byte)(unsafe.Pointer(&_zero)) |
| } |
| } |
| var rsa RawSockaddrAny |
| n, oobn, recvflags, err = recvmsgRaw(fd, iov, oob, flags, &rsa) |
| if err == nil && rsa.Addr.Family != AF_UNSPEC { |
| from, err = anyToSockaddr(fd, &rsa) |
| } |
| return |
| } |
| |
| // Sendmsg sends a message on a socket to an address using the sendmsg system |
| // call. This function is equivalent to SendmsgN, but does not return the |
| // number of bytes actually sent. |
| func Sendmsg(fd int, p, oob []byte, to Sockaddr, flags int) (err error) { |
| _, err = SendmsgN(fd, p, oob, to, flags) |
| return |
| } |
| |
| // SendmsgN sends a message on a socket to an address using the sendmsg system |
| // call. p contains the non-control data to send, and oob contains the "out of |
| // band" control data. The flags are passed to sendmsg. The number of |
| // non-control bytes actually written to the socket is returned. |
| // |
| // Some socket types do not support sending control data without accompanying |
| // non-control data. If p is empty, and oob contains control data, and the |
| // underlying socket type is not SOCK_DGRAM, p will be treated as containing a |
| // single '\0' and the return value will indicate zero bytes sent. |
| // |
| // The Go function Recvmsg, if called with an empty p and a non-empty oob, |
| // will read and ignore this additional '\0'. If the message is received by |
| // code that does not use Recvmsg, or that does not use Go at all, that code |
| // will need to be written to expect and ignore the additional '\0'. |
| // |
| // If you need to send non-empty oob with p actually empty, and if the |
| // underlying socket type supports it, you can do so via a raw system call as |
| // follows: |
| // |
| // msg := &unix.Msghdr{ |
| // Control: &oob[0], |
| // } |
| // msg.SetControllen(len(oob)) |
| // n, _, errno := unix.Syscall(unix.SYS_SENDMSG, uintptr(fd), uintptr(unsafe.Pointer(msg)), flags) |
| func SendmsgN(fd int, p, oob []byte, to Sockaddr, flags int) (n int, err error) { |
| var iov [1]Iovec |
| if len(p) > 0 { |
| iov[0].Base = &p[0] |
| iov[0].SetLen(len(p)) |
| } |
| var ptr unsafe.Pointer |
| var salen _Socklen |
| if to != nil { |
| ptr, salen, err = to.sockaddr() |
| if err != nil { |
| return 0, err |
| } |
| } |
| return sendmsgN(fd, iov[:], oob, ptr, salen, flags) |
| } |
| |
| // SendmsgBuffers sends a message on a socket to an address using the sendmsg |
| // system call. This function is equivalent to SendmsgN, but the non-control |
| // data is gathered from buffers. |
| func SendmsgBuffers(fd int, buffers [][]byte, oob []byte, to Sockaddr, flags int) (n int, err error) { |
| iov := make([]Iovec, len(buffers)) |
| for i := range buffers { |
| if len(buffers[i]) > 0 { |
| iov[i].Base = &buffers[i][0] |
| iov[i].SetLen(len(buffers[i])) |
| } else { |
| iov[i].Base = (*byte)(unsafe.Pointer(&_zero)) |
| } |
| } |
| var ptr unsafe.Pointer |
| var salen _Socklen |
| if to != nil { |
| ptr, salen, err = to.sockaddr() |
| if err != nil { |
| return 0, err |
| } |
| } |
| return sendmsgN(fd, iov, oob, ptr, salen, flags) |
| } |
| |
| func Send(s int, buf []byte, flags int) (err error) { |
| return sendto(s, buf, flags, nil, 0) |
| } |
| |
| func Sendto(fd int, p []byte, flags int, to Sockaddr) (err error) { |
| var ptr unsafe.Pointer |
| var salen _Socklen |
| if to != nil { |
| ptr, salen, err = to.sockaddr() |
| if err != nil { |
| return err |
| } |
| } |
| return sendto(fd, p, flags, ptr, salen) |
| } |
| |
| func SetsockoptByte(fd, level, opt int, value byte) (err error) { |
| return setsockopt(fd, level, opt, unsafe.Pointer(&value), 1) |
| } |
| |
| func SetsockoptInt(fd, level, opt int, value int) (err error) { |
| var n = int32(value) |
| return setsockopt(fd, level, opt, unsafe.Pointer(&n), 4) |
| } |
| |
| func SetsockoptInet4Addr(fd, level, opt int, value [4]byte) (err error) { |
| return setsockopt(fd, level, opt, unsafe.Pointer(&value[0]), 4) |
| } |
| |
| func SetsockoptIPMreq(fd, level, opt int, mreq *IPMreq) (err error) { |
| return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPMreq) |
| } |
| |
| func SetsockoptIPv6Mreq(fd, level, opt int, mreq *IPv6Mreq) (err error) { |
| return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPv6Mreq) |
| } |
| |
| func SetsockoptICMPv6Filter(fd, level, opt int, filter *ICMPv6Filter) error { |
| return setsockopt(fd, level, opt, unsafe.Pointer(filter), SizeofICMPv6Filter) |
| } |
| |
| func SetsockoptLinger(fd, level, opt int, l *Linger) (err error) { |
| return setsockopt(fd, level, opt, unsafe.Pointer(l), SizeofLinger) |
| } |
| |
| func SetsockoptString(fd, level, opt int, s string) (err error) { |
| var p unsafe.Pointer |
| if len(s) > 0 { |
| p = unsafe.Pointer(&[]byte(s)[0]) |
| } |
| return setsockopt(fd, level, opt, p, uintptr(len(s))) |
| } |
| |
| func SetsockoptTimeval(fd, level, opt int, tv *Timeval) (err error) { |
| return setsockopt(fd, level, opt, unsafe.Pointer(tv), unsafe.Sizeof(*tv)) |
| } |
| |
| func SetsockoptUint64(fd, level, opt int, value uint64) (err error) { |
| return setsockopt(fd, level, opt, unsafe.Pointer(&value), 8) |
| } |
| |
| func Socket(domain, typ, proto int) (fd int, err error) { |
| if domain == AF_INET6 && SocketDisableIPv6 { |
| return -1, EAFNOSUPPORT |
| } |
| fd, err = socket(domain, typ, proto) |
| return |
| } |
| |
| func Socketpair(domain, typ, proto int) (fd [2]int, err error) { |
| var fdx [2]int32 |
| err = socketpair(domain, typ, proto, &fdx) |
| if err == nil { |
| fd[0] = int(fdx[0]) |
| fd[1] = int(fdx[1]) |
| } |
| return |
| } |
| |
| var ioSync int64 |
| |
| func CloseOnExec(fd int) { fcntl(fd, F_SETFD, FD_CLOEXEC) } |
| |
| func SetNonblock(fd int, nonblocking bool) (err error) { |
| flag, err := fcntl(fd, F_GETFL, 0) |
| if err != nil { |
| return err |
| } |
| if nonblocking { |
| flag |= O_NONBLOCK |
| } else { |
| flag &= ^O_NONBLOCK |
| } |
| _, err = fcntl(fd, F_SETFL, flag) |
| return err |
| } |
| |
| // Exec calls execve(2), which replaces the calling executable in the process |
| // tree. argv0 should be the full path to an executable ("/bin/ls") and the |
| // executable name should also be the first argument in argv (["ls", "-l"]). |
| // envv are the environment variables that should be passed to the new |
| // process (["USER=go", "PWD=/tmp"]). |
| func Exec(argv0 string, argv []string, envv []string) error { |
| return syscall.Exec(argv0, argv, envv) |
| } |
| |
| // Lutimes sets the access and modification times tv on path. If path refers to |
| // a symlink, it is not dereferenced and the timestamps are set on the symlink. |
| // If tv is nil, the access and modification times are set to the current time. |
| // Otherwise tv must contain exactly 2 elements, with access time as the first |
| // element and modification time as the second element. |
| func Lutimes(path string, tv []Timeval) error { |
| if tv == nil { |
| return UtimesNanoAt(AT_FDCWD, path, nil, AT_SYMLINK_NOFOLLOW) |
| } |
| if len(tv) != 2 { |
| return EINVAL |
| } |
| ts := []Timespec{ |
| NsecToTimespec(TimevalToNsec(tv[0])), |
| NsecToTimespec(TimevalToNsec(tv[1])), |
| } |
| return UtimesNanoAt(AT_FDCWD, path, ts, AT_SYMLINK_NOFOLLOW) |
| } |
| |
| // emptyIovecs reports whether there are no bytes in the slice of Iovec. |
| func emptyIovecs(iov []Iovec) bool { |
| for i := range iov { |
| if iov[i].Len > 0 { |
| return false |
| } |
| } |
| return true |
| } |