[github/fretlink/terraform-provider-statuscake.git] / vendor / golang.org / x / sys / unix / syscall_unix.go

// 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.

// +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)
		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
	}

	// Slice memory layout
	var sl = struct {
		addr uintptr
		len  int
		cap  int
	}{addr, length, length}

	// Use unsafe to turn sl into a []byte.
	b := *(*[]byte)(unsafe.Pointer(&sl))

	// 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
}

// 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
}

func Sendto(fd int, p []byte, flags int, to Sockaddr) (err error) {
	ptr, n, err := to.sockaddr()
	if err != nil {
		return err
	}
	return sendto(fd, p, flags, ptr, n)
}

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)
}
Commit	Line	Data
15c0b25d AP	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"
15c0b25d AP	11	"sort"
	12	"sync"
	13	"syscall"
	14	"unsafe"
	15	)
	16
	17	var (
	18	Stdin = 0
	19	Stdout = 1
	20	Stderr = 2
	21	)
	22
15c0b25d AP	23	// Do the interface allocations only once for common
	24	// Errno values.
	25	var (
	26	errEAGAIN error = syscall.EAGAIN
	27	errEINVAL error = syscall.EINVAL
	28	errENOENT error = syscall.ENOENT
	29	)
	30
107c1cdb ND	31	var (
	32	signalNameMapOnce sync.Once
	33	signalNameMap map[string]syscall.Signal
	34	)
	35
15c0b25d AP	36	// errnoErr returns common boxed Errno values, to prevent
	37	// allocations at runtime.
	38	func errnoErr(e syscall.Errno) error {
	39	switch e {
	40	case 0:
	41	return nil
	42	case EAGAIN:
	43	return errEAGAIN
	44	case EINVAL:
	45	return errEINVAL
	46	case ENOENT:
	47	return errENOENT
	48	}
	49	return e
	50	}
	51
	52	// ErrnoName returns the error name for error number e.
	53	func ErrnoName(e syscall.Errno) string {
	54	i := sort.Search(len(errorList), func(i int) bool {
	55	return errorList[i].num >= e
	56	})
	57	if i < len(errorList) && errorList[i].num == e {
	58	return errorList[i].name
	59	}
	60	return ""
	61	}
	62
	63	// SignalName returns the signal name for signal number s.
	64	func SignalName(s syscall.Signal) string {
	65	i := sort.Search(len(signalList), func(i int) bool {
	66	return signalList[i].num >= s
	67	})
	68	if i < len(signalList) && signalList[i].num == s {
	69	return signalList[i].name
	70	}
	71	return ""
	72	}
	73
107c1cdb ND	74	// SignalNum returns the syscall.Signal for signal named s,
	75	// or 0 if a signal with such name is not found.
	76	// The signal name should start with "SIG".
	77	func SignalNum(s string) syscall.Signal {
	78	signalNameMapOnce.Do(func() {
	79	signalNameMap = make(map[string]syscall.Signal)
	80	for _, signal := range signalList {
	81	signalNameMap[signal.name] = signal.num
	82	}
	83	})
	84	return signalNameMap[s]
	85	}
	86
15c0b25d AP	87	// clen returns the index of the first NULL byte in n or len(n) if n contains no NULL byte.
	88	func clen(n []byte) int {
	89	i := bytes.IndexByte(n, 0)
	90	if i == -1 {
	91	i = len(n)
	92	}
	93	return i
	94	}
	95
	96	// Mmap manager, for use by operating system-specific implementations.
	97
	98	type mmapper struct {
	99	sync.Mutex
	100	active map[*byte][]byte // active mappings; key is last byte in mapping
	101	mmap func(addr, length uintptr, prot, flags, fd int, offset int64) (uintptr, error)
	102	munmap func(addr uintptr, length uintptr) error
	103	}
	104
	105	func (m *mmapper) Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) {
	106	if length <= 0 {
	107	return nil, EINVAL
	108	}
	109
	110	// Map the requested memory.
	111	addr, errno := m.mmap(0, uintptr(length), prot, flags, fd, offset)
	112	if errno != nil {
	113	return nil, errno
	114	}
	115
	116	// Slice memory layout
	117	var sl = struct {
	118	addr uintptr
	119	len int
	120	cap int
	121	}{addr, length, length}
	122
	123	// Use unsafe to turn sl into a []byte.
	124	b := ([]byte)(unsafe.Pointer(&sl))
	125
	126	// Register mapping in m and return it.
	127	p := &b[cap(b)-1]
	128	m.Lock()
	129	defer m.Unlock()
	130	m.active[p] = b
	131	return b, nil
	132	}
	133
	134	func (m *mmapper) Munmap(data []byte) (err error) {
	135	if len(data) == 0 \|\| len(data) != cap(data) {
	136	return EINVAL
	137	}
	138
	139	// Find the base of the mapping.
	140	p := &data[cap(data)-1]
	141	m.Lock()
	142	defer m.Unlock()
	143	b := m.active[p]
	144	if b == nil \|\| &b[0] != &data[0] {
	145	return EINVAL
	146	}
	147
	148	// Unmap the memory and update m.
	149	if errno := m.munmap(uintptr(unsafe.Pointer(&b[0])), uintptr(len(b))); errno != nil {
	150	return errno
151	}
152	delete(m.active, p)
153	return nil
154	}
155
156	func Read(fd int, p []byte) (n int, err error) {
157	n, err = read(fd, p)
158	if raceenabled {
159	if n > 0 {
160	raceWriteRange(unsafe.Pointer(&p[0]), n)
161	}
162	if err == nil {
163	raceAcquire(unsafe.Pointer(&ioSync))
164	}
165	}
166	return
167	}
168
169	func Write(fd int, p []byte) (n int, err error) {
170	if raceenabled {
171	raceReleaseMerge(unsafe.Pointer(&ioSync))
172	}
173	n, err = write(fd, p)
174	if raceenabled && n > 0 {
175	raceReadRange(unsafe.Pointer(&p[0]), n)
176	}
177	return
178	}
179
180	// For testing: clients can set this flag to force
181	// creation of IPv6 sockets to return EAFNOSUPPORT.
182	var SocketDisableIPv6 bool
183
184	// Sockaddr represents a socket address.
185	type Sockaddr interface {
186	sockaddr() (ptr unsafe.Pointer, len _Socklen, err error) // lowercase; only we can define Sockaddrs
187	}
188
189	// SockaddrInet4 implements the Sockaddr interface for AF_INET type sockets.
190	type SockaddrInet4 struct {
191	Port int
192	Addr [4]byte
193	raw RawSockaddrInet4
194	}
195
196	// SockaddrInet6 implements the Sockaddr interface for AF_INET6 type sockets.
197	type SockaddrInet6 struct {
198	Port int
199	ZoneId uint32
200	Addr [16]byte
201	raw RawSockaddrInet6
202	}
203
204	// SockaddrUnix implements the Sockaddr interface for AF_UNIX type sockets.
205	type SockaddrUnix struct {
206	Name string
207	raw RawSockaddrUnix
208	}
209
210	func Bind(fd int, sa Sockaddr) (err error) {
211	ptr, n, err := sa.sockaddr()
212	if err != nil {
213	return err
214	}
215	return bind(fd, ptr, n)
216	}
217
218	func Connect(fd int, sa Sockaddr) (err error) {
219	ptr, n, err := sa.sockaddr()
220	if err != nil {
221	return err
222	}
223	return connect(fd, ptr, n)
224	}
225
226	func Getpeername(fd int) (sa Sockaddr, err error) {
227	var rsa RawSockaddrAny
228	var len _Socklen = SizeofSockaddrAny
229	if err = getpeername(fd, &rsa, &len); err != nil {
230	return
231	}
232	return anyToSockaddr(fd, &rsa)
233	}
234
235	func GetsockoptByte(fd, level, opt int) (value byte, err error) {
236	var n byte
237	vallen := _Socklen(1)
238	err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen)
239	return n, err
240	}
241
242	func GetsockoptInt(fd, level, opt int) (value int, err error) {
243	var n int32
244	vallen := _Socklen(4)
245	err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen)
246	return int(n), err
247	}
248
249	func GetsockoptInet4Addr(fd, level, opt int) (value [4]byte, err error) {
250	vallen := _Socklen(4)
251	err = getsockopt(fd, level, opt, unsafe.Pointer(&value[0]), &vallen)
252	return value, err
253	}
254
255	func GetsockoptIPMreq(fd, level, opt int) (*IPMreq, error) {
256	var value IPMreq
257	vallen := _Socklen(SizeofIPMreq)
258	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
259	return &value, err
260	}
261
262	func GetsockoptIPv6Mreq(fd, level, opt int) (*IPv6Mreq, error) {
263	var value IPv6Mreq
264	vallen := _Socklen(SizeofIPv6Mreq)
265	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
266	return &value, err
267	}
268
269	func GetsockoptIPv6MTUInfo(fd, level, opt int) (*IPv6MTUInfo, error) {
270	var value IPv6MTUInfo
271	vallen := _Socklen(SizeofIPv6MTUInfo)
272	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
273	return &value, err
274	}
275
276	func GetsockoptICMPv6Filter(fd, level, opt int) (*ICMPv6Filter, error) {
277	var value ICMPv6Filter
278	vallen := _Socklen(SizeofICMPv6Filter)
279	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
280	return &value, err
281	}
282
283	func GetsockoptLinger(fd, level, opt int) (*Linger, error) {
284	var linger Linger
285	vallen := _Socklen(SizeofLinger)
286	err := getsockopt(fd, level, opt, unsafe.Pointer(&linger), &vallen)
287	return &linger, err
288	}
289
290	func GetsockoptTimeval(fd, level, opt int) (*Timeval, error) {
291	var tv Timeval
292	vallen := _Socklen(unsafe.Sizeof(tv))
293	err := getsockopt(fd, level, opt, unsafe.Pointer(&tv), &vallen)
294	return &tv, err
295	}
296
107c1cdb ND	297	func GetsockoptUint64(fd, level, opt int) (value uint64, err error) {
	298	var n uint64
	299	vallen := _Socklen(8)
	300	err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen)
	301	return n, err
	302	}
	303
15c0b25d AP	304	func Recvfrom(fd int, p []byte, flags int) (n int, from Sockaddr, err error) {
	305	var rsa RawSockaddrAny
	306	var len _Socklen = SizeofSockaddrAny
	307	if n, err = recvfrom(fd, p, flags, &rsa, &len); err != nil {
	308	return
	309	}
	310	if rsa.Addr.Family != AF_UNSPEC {
	311	from, err = anyToSockaddr(fd, &rsa)
	312	}
	313	return
	314	}
	315
	316	func Sendto(fd int, p []byte, flags int, to Sockaddr) (err error) {
	317	ptr, n, err := to.sockaddr()
	318	if err != nil {
	319	return err
	320	}
	321	return sendto(fd, p, flags, ptr, n)
	322	}
	323
	324	func SetsockoptByte(fd, level, opt int, value byte) (err error) {
	325	return setsockopt(fd, level, opt, unsafe.Pointer(&value), 1)
	326	}
	327
	328	func SetsockoptInt(fd, level, opt int, value int) (err error) {
	329	var n = int32(value)
	330	return setsockopt(fd, level, opt, unsafe.Pointer(&n), 4)
	331	}
	332
	333	func SetsockoptInet4Addr(fd, level, opt int, value [4]byte) (err error) {
	334	return setsockopt(fd, level, opt, unsafe.Pointer(&value[0]), 4)
	335	}
	336
	337	func SetsockoptIPMreq(fd, level, opt int, mreq *IPMreq) (err error) {
	338	return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPMreq)
	339	}
	340
	341	func SetsockoptIPv6Mreq(fd, level, opt int, mreq *IPv6Mreq) (err error) {
	342	return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPv6Mreq)
	343	}
	344
	345	func SetsockoptICMPv6Filter(fd, level, opt int, filter *ICMPv6Filter) error {
	346	return setsockopt(fd, level, opt, unsafe.Pointer(filter), SizeofICMPv6Filter)
	347	}
	348
	349	func SetsockoptLinger(fd, level, opt int, l *Linger) (err error) {
	350	return setsockopt(fd, level, opt, unsafe.Pointer(l), SizeofLinger)
	351	}
	352
	353	func SetsockoptString(fd, level, opt int, s string) (err error) {
107c1cdb ND	354	var p unsafe.Pointer
	355	if len(s) > 0 {
	356	p = unsafe.Pointer(&[]byte(s)[0])
	357	}
	358	return setsockopt(fd, level, opt, p, uintptr(len(s)))
15c0b25d AP	359	}
	360
	361	func SetsockoptTimeval(fd, level, opt int, tv *Timeval) (err error) {
	362	return setsockopt(fd, level, opt, unsafe.Pointer(tv), unsafe.Sizeof(*tv))
	363	}
	364
107c1cdb ND	365	func SetsockoptUint64(fd, level, opt int, value uint64) (err error) {
	366	return setsockopt(fd, level, opt, unsafe.Pointer(&value), 8)
	367	}
	368
15c0b25d AP	369	func Socket(domain, typ, proto int) (fd int, err error) {
	370	if domain == AF_INET6 && SocketDisableIPv6 {
	371	return -1, EAFNOSUPPORT
	372	}
	373	fd, err = socket(domain, typ, proto)
	374	return
	375	}
	376
	377	func Socketpair(domain, typ, proto int) (fd [2]int, err error) {
	378	var fdx [2]int32
	379	err = socketpair(domain, typ, proto, &fdx)
	380	if err == nil {
	381	fd[0] = int(fdx[0])
	382	fd[1] = int(fdx[1])
	383	}
	384	return
	385	}
	386
15c0b25d AP	387	var ioSync int64
	388
	389	func CloseOnExec(fd int) { fcntl(fd, F_SETFD, FD_CLOEXEC) }
	390
	391	func SetNonblock(fd int, nonblocking bool) (err error) {
	392	flag, err := fcntl(fd, F_GETFL, 0)
	393	if err != nil {
	394	return err
	395	}
	396	if nonblocking {
	397	flag \|= O_NONBLOCK
	398	} else {
	399	flag &= ^O_NONBLOCK
	400	}
	401	_, err = fcntl(fd, F_SETFL, flag)
	402	return err
	403	}
	404
	405	// Exec calls execve(2), which replaces the calling executable in the process
	406	// tree. argv0 should be the full path to an executable ("/bin/ls") and the
	407	// executable name should also be the first argument in argv (["ls", "-l"]).
	408	// envv are the environment variables that should be passed to the new
	409	// process (["USER=go", "PWD=/tmp"]).
	410	func Exec(argv0 string, argv []string, envv []string) error {
	411	return syscall.Exec(argv0, argv, envv)
	412	}
107c1cdb ND	413
	414	// Lutimes sets the access and modification times tv on path. If path refers to
	415	// a symlink, it is not dereferenced and the timestamps are set on the symlink.
	416	// If tv is nil, the access and modification times are set to the current time.
	417	// Otherwise tv must contain exactly 2 elements, with access time as the first
	418	// element and modification time as the second element.
	419	func Lutimes(path string, tv []Timeval) error {
	420	if tv == nil {
	421	return UtimesNanoAt(AT_FDCWD, path, nil, AT_SYMLINK_NOFOLLOW)
	422	}
	423	if len(tv) != 2 {
	424	return EINVAL
	425	}
	426	ts := []Timespec{
	427	NsecToTimespec(TimevalToNsec(tv[0])),
	428	NsecToTimespec(TimevalToNsec(tv[1])),
	429	}
	430	return UtimesNanoAt(AT_FDCWD, path, ts, AT_SYMLINK_NOFOLLOW)
	431	}