Source file src/cmd/vendor/golang.org/x/sys/unix/syscall_bsd.go

     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 netbsd openbsd
     6	
     7	// BSD system call wrappers shared by *BSD based systems
     8	// including OS X (Darwin) and FreeBSD.  Like the other
     9	// syscall_*.go files it is compiled as Go code but also
    10	// used as input to mksyscall which parses the //sys
    11	// lines and generates system call stubs.
    12	
    13	package unix
    14	
    15	import (
    16		"runtime"
    17		"syscall"
    18		"unsafe"
    19	)
    20	
    21	/*
    22	 * Wrapped
    23	 */
    24	
    25	//sysnb	getgroups(ngid int, gid *_Gid_t) (n int, err error)
    26	//sysnb	setgroups(ngid int, gid *_Gid_t) (err error)
    27	
    28	func Getgroups() (gids []int, err error) {
    29		n, err := getgroups(0, nil)
    30		if err != nil {
    31			return nil, err
    32		}
    33		if n == 0 {
    34			return nil, nil
    35		}
    36	
    37		// Sanity check group count. Max is 16 on BSD.
    38		if n < 0 || n > 1000 {
    39			return nil, EINVAL
    40		}
    41	
    42		a := make([]_Gid_t, n)
    43		n, err = getgroups(n, &a[0])
    44		if err != nil {
    45			return nil, err
    46		}
    47		gids = make([]int, n)
    48		for i, v := range a[0:n] {
    49			gids[i] = int(v)
    50		}
    51		return
    52	}
    53	
    54	func Setgroups(gids []int) (err error) {
    55		if len(gids) == 0 {
    56			return setgroups(0, nil)
    57		}
    58	
    59		a := make([]_Gid_t, len(gids))
    60		for i, v := range gids {
    61			a[i] = _Gid_t(v)
    62		}
    63		return setgroups(len(a), &a[0])
    64	}
    65	
    66	func ReadDirent(fd int, buf []byte) (n int, err error) {
    67		// Final argument is (basep *uintptr) and the syscall doesn't take nil.
    68		// 64 bits should be enough. (32 bits isn't even on 386). Since the
    69		// actual system call is getdirentries64, 64 is a good guess.
    70		// TODO(rsc): Can we use a single global basep for all calls?
    71		var base = (*uintptr)(unsafe.Pointer(new(uint64)))
    72		return Getdirentries(fd, buf, base)
    73	}
    74	
    75	// Wait status is 7 bits at bottom, either 0 (exited),
    76	// 0x7F (stopped), or a signal number that caused an exit.
    77	// The 0x80 bit is whether there was a core dump.
    78	// An extra number (exit code, signal causing a stop)
    79	// is in the high bits.
    80	
    81	type WaitStatus uint32
    82	
    83	const (
    84		mask  = 0x7F
    85		core  = 0x80
    86		shift = 8
    87	
    88		exited  = 0
    89		stopped = 0x7F
    90	)
    91	
    92	func (w WaitStatus) Exited() bool { return w&mask == exited }
    93	
    94	func (w WaitStatus) ExitStatus() int {
    95		if w&mask != exited {
    96			return -1
    97		}
    98		return int(w >> shift)
    99	}
   100	
   101	func (w WaitStatus) Signaled() bool { return w&mask != stopped && w&mask != 0 }
   102	
   103	func (w WaitStatus) Signal() syscall.Signal {
   104		sig := syscall.Signal(w & mask)
   105		if sig == stopped || sig == 0 {
   106			return -1
   107		}
   108		return sig
   109	}
   110	
   111	func (w WaitStatus) CoreDump() bool { return w.Signaled() && w&core != 0 }
   112	
   113	func (w WaitStatus) Stopped() bool { return w&mask == stopped && syscall.Signal(w>>shift) != SIGSTOP }
   114	
   115	func (w WaitStatus) Continued() bool { return w&mask == stopped && syscall.Signal(w>>shift) == SIGSTOP }
   116	
   117	func (w WaitStatus) StopSignal() syscall.Signal {
   118		if !w.Stopped() {
   119			return -1
   120		}
   121		return syscall.Signal(w>>shift) & 0xFF
   122	}
   123	
   124	func (w WaitStatus) TrapCause() int { return -1 }
   125	
   126	//sys	wait4(pid int, wstatus *_C_int, options int, rusage *Rusage) (wpid int, err error)
   127	
   128	func Wait4(pid int, wstatus *WaitStatus, options int, rusage *Rusage) (wpid int, err error) {
   129		var status _C_int
   130		wpid, err = wait4(pid, &status, options, rusage)
   131		if wstatus != nil {
   132			*wstatus = WaitStatus(status)
   133		}
   134		return
   135	}
   136	
   137	//sys	accept(s int, rsa *RawSockaddrAny, addrlen *_Socklen) (fd int, err error)
   138	//sys	bind(s int, addr unsafe.Pointer, addrlen _Socklen) (err error)
   139	//sys	connect(s int, addr unsafe.Pointer, addrlen _Socklen) (err error)
   140	//sysnb	socket(domain int, typ int, proto int) (fd int, err error)
   141	//sys	getsockopt(s int, level int, name int, val unsafe.Pointer, vallen *_Socklen) (err error)
   142	//sys	setsockopt(s int, level int, name int, val unsafe.Pointer, vallen uintptr) (err error)
   143	//sysnb	getpeername(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error)
   144	//sysnb	getsockname(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error)
   145	//sys	Shutdown(s int, how int) (err error)
   146	
   147	func (sa *SockaddrInet4) sockaddr() (unsafe.Pointer, _Socklen, error) {
   148		if sa.Port < 0 || sa.Port > 0xFFFF {
   149			return nil, 0, EINVAL
   150		}
   151		sa.raw.Len = SizeofSockaddrInet4
   152		sa.raw.Family = AF_INET
   153		p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port))
   154		p[0] = byte(sa.Port >> 8)
   155		p[1] = byte(sa.Port)
   156		for i := 0; i < len(sa.Addr); i++ {
   157			sa.raw.Addr[i] = sa.Addr[i]
   158		}
   159		return unsafe.Pointer(&sa.raw), _Socklen(sa.raw.Len), nil
   160	}
   161	
   162	func (sa *SockaddrInet6) sockaddr() (unsafe.Pointer, _Socklen, error) {
   163		if sa.Port < 0 || sa.Port > 0xFFFF {
   164			return nil, 0, EINVAL
   165		}
   166		sa.raw.Len = SizeofSockaddrInet6
   167		sa.raw.Family = AF_INET6
   168		p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port))
   169		p[0] = byte(sa.Port >> 8)
   170		p[1] = byte(sa.Port)
   171		sa.raw.Scope_id = sa.ZoneId
   172		for i := 0; i < len(sa.Addr); i++ {
   173			sa.raw.Addr[i] = sa.Addr[i]
   174		}
   175		return unsafe.Pointer(&sa.raw), _Socklen(sa.raw.Len), nil
   176	}
   177	
   178	func (sa *SockaddrUnix) sockaddr() (unsafe.Pointer, _Socklen, error) {
   179		name := sa.Name
   180		n := len(name)
   181		if n >= len(sa.raw.Path) || n == 0 {
   182			return nil, 0, EINVAL
   183		}
   184		sa.raw.Len = byte(3 + n) // 2 for Family, Len; 1 for NUL
   185		sa.raw.Family = AF_UNIX
   186		for i := 0; i < n; i++ {
   187			sa.raw.Path[i] = int8(name[i])
   188		}
   189		return unsafe.Pointer(&sa.raw), _Socklen(sa.raw.Len), nil
   190	}
   191	
   192	func (sa *SockaddrDatalink) sockaddr() (unsafe.Pointer, _Socklen, error) {
   193		if sa.Index == 0 {
   194			return nil, 0, EINVAL
   195		}
   196		sa.raw.Len = sa.Len
   197		sa.raw.Family = AF_LINK
   198		sa.raw.Index = sa.Index
   199		sa.raw.Type = sa.Type
   200		sa.raw.Nlen = sa.Nlen
   201		sa.raw.Alen = sa.Alen
   202		sa.raw.Slen = sa.Slen
   203		for i := 0; i < len(sa.raw.Data); i++ {
   204			sa.raw.Data[i] = sa.Data[i]
   205		}
   206		return unsafe.Pointer(&sa.raw), SizeofSockaddrDatalink, nil
   207	}
   208	
   209	func anyToSockaddr(fd int, rsa *RawSockaddrAny) (Sockaddr, error) {
   210		switch rsa.Addr.Family {
   211		case AF_LINK:
   212			pp := (*RawSockaddrDatalink)(unsafe.Pointer(rsa))
   213			sa := new(SockaddrDatalink)
   214			sa.Len = pp.Len
   215			sa.Family = pp.Family
   216			sa.Index = pp.Index
   217			sa.Type = pp.Type
   218			sa.Nlen = pp.Nlen
   219			sa.Alen = pp.Alen
   220			sa.Slen = pp.Slen
   221			for i := 0; i < len(sa.Data); i++ {
   222				sa.Data[i] = pp.Data[i]
   223			}
   224			return sa, nil
   225	
   226		case AF_UNIX:
   227			pp := (*RawSockaddrUnix)(unsafe.Pointer(rsa))
   228			if pp.Len < 2 || pp.Len > SizeofSockaddrUnix {
   229				return nil, EINVAL
   230			}
   231			sa := new(SockaddrUnix)
   232	
   233			// Some BSDs include the trailing NUL in the length, whereas
   234			// others do not. Work around this by subtracting the leading
   235			// family and len. The path is then scanned to see if a NUL
   236			// terminator still exists within the length.
   237			n := int(pp.Len) - 2 // subtract leading Family, Len
   238			for i := 0; i < n; i++ {
   239				if pp.Path[i] == 0 {
   240					// found early NUL; assume Len included the NUL
   241					// or was overestimating.
   242					n = i
   243					break
   244				}
   245			}
   246			bytes := (*[10000]byte)(unsafe.Pointer(&pp.Path[0]))[0:n]
   247			sa.Name = string(bytes)
   248			return sa, nil
   249	
   250		case AF_INET:
   251			pp := (*RawSockaddrInet4)(unsafe.Pointer(rsa))
   252			sa := new(SockaddrInet4)
   253			p := (*[2]byte)(unsafe.Pointer(&pp.Port))
   254			sa.Port = int(p[0])<<8 + int(p[1])
   255			for i := 0; i < len(sa.Addr); i++ {
   256				sa.Addr[i] = pp.Addr[i]
   257			}
   258			return sa, nil
   259	
   260		case AF_INET6:
   261			pp := (*RawSockaddrInet6)(unsafe.Pointer(rsa))
   262			sa := new(SockaddrInet6)
   263			p := (*[2]byte)(unsafe.Pointer(&pp.Port))
   264			sa.Port = int(p[0])<<8 + int(p[1])
   265			sa.ZoneId = pp.Scope_id
   266			for i := 0; i < len(sa.Addr); i++ {
   267				sa.Addr[i] = pp.Addr[i]
   268			}
   269			return sa, nil
   270		}
   271		return nil, EAFNOSUPPORT
   272	}
   273	
   274	func Accept(fd int) (nfd int, sa Sockaddr, err error) {
   275		var rsa RawSockaddrAny
   276		var len _Socklen = SizeofSockaddrAny
   277		nfd, err = accept(fd, &rsa, &len)
   278		if err != nil {
   279			return
   280		}
   281		if runtime.GOOS == "darwin" && len == 0 {
   282			// Accepted socket has no address.
   283			// This is likely due to a bug in xnu kernels,
   284			// where instead of ECONNABORTED error socket
   285			// is accepted, but has no address.
   286			Close(nfd)
   287			return 0, nil, ECONNABORTED
   288		}
   289		sa, err = anyToSockaddr(fd, &rsa)
   290		if err != nil {
   291			Close(nfd)
   292			nfd = 0
   293		}
   294		return
   295	}
   296	
   297	func Getsockname(fd int) (sa Sockaddr, err error) {
   298		var rsa RawSockaddrAny
   299		var len _Socklen = SizeofSockaddrAny
   300		if err = getsockname(fd, &rsa, &len); err != nil {
   301			return
   302		}
   303		// TODO(jsing): DragonFly has a "bug" (see issue 3349), which should be
   304		// reported upstream.
   305		if runtime.GOOS == "dragonfly" && rsa.Addr.Family == AF_UNSPEC && rsa.Addr.Len == 0 {
   306			rsa.Addr.Family = AF_UNIX
   307			rsa.Addr.Len = SizeofSockaddrUnix
   308		}
   309		return anyToSockaddr(fd, &rsa)
   310	}
   311	
   312	//sysnb socketpair(domain int, typ int, proto int, fd *[2]int32) (err error)
   313	
   314	// GetsockoptString returns the string value of the socket option opt for the
   315	// socket associated with fd at the given socket level.
   316	func GetsockoptString(fd, level, opt int) (string, error) {
   317		buf := make([]byte, 256)
   318		vallen := _Socklen(len(buf))
   319		err := getsockopt(fd, level, opt, unsafe.Pointer(&buf[0]), &vallen)
   320		if err != nil {
   321			return "", err
   322		}
   323		return string(buf[:vallen-1]), nil
   324	}
   325	
   326	//sys   recvfrom(fd int, p []byte, flags int, from *RawSockaddrAny, fromlen *_Socklen) (n int, err error)
   327	//sys   sendto(s int, buf []byte, flags int, to unsafe.Pointer, addrlen _Socklen) (err error)
   328	//sys	recvmsg(s int, msg *Msghdr, flags int) (n int, err error)
   329	
   330	func Recvmsg(fd int, p, oob []byte, flags int) (n, oobn int, recvflags int, from Sockaddr, err error) {
   331		var msg Msghdr
   332		var rsa RawSockaddrAny
   333		msg.Name = (*byte)(unsafe.Pointer(&rsa))
   334		msg.Namelen = uint32(SizeofSockaddrAny)
   335		var iov Iovec
   336		if len(p) > 0 {
   337			iov.Base = (*byte)(unsafe.Pointer(&p[0]))
   338			iov.SetLen(len(p))
   339		}
   340		var dummy byte
   341		if len(oob) > 0 {
   342			// receive at least one normal byte
   343			if len(p) == 0 {
   344				iov.Base = &dummy
   345				iov.SetLen(1)
   346			}
   347			msg.Control = (*byte)(unsafe.Pointer(&oob[0]))
   348			msg.SetControllen(len(oob))
   349		}
   350		msg.Iov = &iov
   351		msg.Iovlen = 1
   352		if n, err = recvmsg(fd, &msg, flags); err != nil {
   353			return
   354		}
   355		oobn = int(msg.Controllen)
   356		recvflags = int(msg.Flags)
   357		// source address is only specified if the socket is unconnected
   358		if rsa.Addr.Family != AF_UNSPEC {
   359			from, err = anyToSockaddr(fd, &rsa)
   360		}
   361		return
   362	}
   363	
   364	//sys	sendmsg(s int, msg *Msghdr, flags int) (n int, err error)
   365	
   366	func Sendmsg(fd int, p, oob []byte, to Sockaddr, flags int) (err error) {
   367		_, err = SendmsgN(fd, p, oob, to, flags)
   368		return
   369	}
   370	
   371	func SendmsgN(fd int, p, oob []byte, to Sockaddr, flags int) (n int, err error) {
   372		var ptr unsafe.Pointer
   373		var salen _Socklen
   374		if to != nil {
   375			ptr, salen, err = to.sockaddr()
   376			if err != nil {
   377				return 0, err
   378			}
   379		}
   380		var msg Msghdr
   381		msg.Name = (*byte)(unsafe.Pointer(ptr))
   382		msg.Namelen = uint32(salen)
   383		var iov Iovec
   384		if len(p) > 0 {
   385			iov.Base = (*byte)(unsafe.Pointer(&p[0]))
   386			iov.SetLen(len(p))
   387		}
   388		var dummy byte
   389		if len(oob) > 0 {
   390			// send at least one normal byte
   391			if len(p) == 0 {
   392				iov.Base = &dummy
   393				iov.SetLen(1)
   394			}
   395			msg.Control = (*byte)(unsafe.Pointer(&oob[0]))
   396			msg.SetControllen(len(oob))
   397		}
   398		msg.Iov = &iov
   399		msg.Iovlen = 1
   400		if n, err = sendmsg(fd, &msg, flags); err != nil {
   401			return 0, err
   402		}
   403		if len(oob) > 0 && len(p) == 0 {
   404			n = 0
   405		}
   406		return n, nil
   407	}
   408	
   409	//sys	kevent(kq int, change unsafe.Pointer, nchange int, event unsafe.Pointer, nevent int, timeout *Timespec) (n int, err error)
   410	
   411	func Kevent(kq int, changes, events []Kevent_t, timeout *Timespec) (n int, err error) {
   412		var change, event unsafe.Pointer
   413		if len(changes) > 0 {
   414			change = unsafe.Pointer(&changes[0])
   415		}
   416		if len(events) > 0 {
   417			event = unsafe.Pointer(&events[0])
   418		}
   419		return kevent(kq, change, len(changes), event, len(events), timeout)
   420	}
   421	
   422	//sys	sysctl(mib []_C_int, old *byte, oldlen *uintptr, new *byte, newlen uintptr) (err error) = SYS___SYSCTL
   423	
   424	// sysctlmib translates name to mib number and appends any additional args.
   425	func sysctlmib(name string, args ...int) ([]_C_int, error) {
   426		// Translate name to mib number.
   427		mib, err := nametomib(name)
   428		if err != nil {
   429			return nil, err
   430		}
   431	
   432		for _, a := range args {
   433			mib = append(mib, _C_int(a))
   434		}
   435	
   436		return mib, nil
   437	}
   438	
   439	func Sysctl(name string) (string, error) {
   440		return SysctlArgs(name)
   441	}
   442	
   443	func SysctlArgs(name string, args ...int) (string, error) {
   444		buf, err := SysctlRaw(name, args...)
   445		if err != nil {
   446			return "", err
   447		}
   448		n := len(buf)
   449	
   450		// Throw away terminating NUL.
   451		if n > 0 && buf[n-1] == '\x00' {
   452			n--
   453		}
   454		return string(buf[0:n]), nil
   455	}
   456	
   457	func SysctlUint32(name string) (uint32, error) {
   458		return SysctlUint32Args(name)
   459	}
   460	
   461	func SysctlUint32Args(name string, args ...int) (uint32, error) {
   462		mib, err := sysctlmib(name, args...)
   463		if err != nil {
   464			return 0, err
   465		}
   466	
   467		n := uintptr(4)
   468		buf := make([]byte, 4)
   469		if err := sysctl(mib, &buf[0], &n, nil, 0); err != nil {
   470			return 0, err
   471		}
   472		if n != 4 {
   473			return 0, EIO
   474		}
   475		return *(*uint32)(unsafe.Pointer(&buf[0])), nil
   476	}
   477	
   478	func SysctlUint64(name string, args ...int) (uint64, error) {
   479		mib, err := sysctlmib(name, args...)
   480		if err != nil {
   481			return 0, err
   482		}
   483	
   484		n := uintptr(8)
   485		buf := make([]byte, 8)
   486		if err := sysctl(mib, &buf[0], &n, nil, 0); err != nil {
   487			return 0, err
   488		}
   489		if n != 8 {
   490			return 0, EIO
   491		}
   492		return *(*uint64)(unsafe.Pointer(&buf[0])), nil
   493	}
   494	
   495	func SysctlRaw(name string, args ...int) ([]byte, error) {
   496		mib, err := sysctlmib(name, args...)
   497		if err != nil {
   498			return nil, err
   499		}
   500	
   501		// Find size.
   502		n := uintptr(0)
   503		if err := sysctl(mib, nil, &n, nil, 0); err != nil {
   504			return nil, err
   505		}
   506		if n == 0 {
   507			return nil, nil
   508		}
   509	
   510		// Read into buffer of that size.
   511		buf := make([]byte, n)
   512		if err := sysctl(mib, &buf[0], &n, nil, 0); err != nil {
   513			return nil, err
   514		}
   515	
   516		// The actual call may return less than the original reported required
   517		// size so ensure we deal with that.
   518		return buf[:n], nil
   519	}
   520	
   521	//sys	utimes(path string, timeval *[2]Timeval) (err error)
   522	
   523	func Utimes(path string, tv []Timeval) error {
   524		if tv == nil {
   525			return utimes(path, nil)
   526		}
   527		if len(tv) != 2 {
   528			return EINVAL
   529		}
   530		return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
   531	}
   532	
   533	func UtimesNano(path string, ts []Timespec) error {
   534		if ts == nil {
   535			err := utimensat(AT_FDCWD, path, nil, 0)
   536			if err != ENOSYS {
   537				return err
   538			}
   539			return utimes(path, nil)
   540		}
   541		if len(ts) != 2 {
   542			return EINVAL
   543		}
   544		// Darwin setattrlist can set nanosecond timestamps
   545		err := setattrlistTimes(path, ts, 0)
   546		if err != ENOSYS {
   547			return err
   548		}
   549		err = utimensat(AT_FDCWD, path, (*[2]Timespec)(unsafe.Pointer(&ts[0])), 0)
   550		if err != ENOSYS {
   551			return err
   552		}
   553		// Not as efficient as it could be because Timespec and
   554		// Timeval have different types in the different OSes
   555		tv := [2]Timeval{
   556			NsecToTimeval(TimespecToNsec(ts[0])),
   557			NsecToTimeval(TimespecToNsec(ts[1])),
   558		}
   559		return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
   560	}
   561	
   562	func UtimesNanoAt(dirfd int, path string, ts []Timespec, flags int) error {
   563		if ts == nil {
   564			return utimensat(dirfd, path, nil, flags)
   565		}
   566		if len(ts) != 2 {
   567			return EINVAL
   568		}
   569		err := setattrlistTimes(path, ts, flags)
   570		if err != ENOSYS {
   571			return err
   572		}
   573		return utimensat(dirfd, path, (*[2]Timespec)(unsafe.Pointer(&ts[0])), flags)
   574	}
   575	
   576	//sys	futimes(fd int, timeval *[2]Timeval) (err error)
   577	
   578	func Futimes(fd int, tv []Timeval) error {
   579		if tv == nil {
   580			return futimes(fd, nil)
   581		}
   582		if len(tv) != 2 {
   583			return EINVAL
   584		}
   585		return futimes(fd, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
   586	}
   587	
   588	//sys	fcntl(fd int, cmd int, arg int) (val int, err error)
   589	
   590	//sys   poll(fds *PollFd, nfds int, timeout int) (n int, err error)
   591	
   592	func Poll(fds []PollFd, timeout int) (n int, err error) {
   593		if len(fds) == 0 {
   594			return poll(nil, 0, timeout)
   595		}
   596		return poll(&fds[0], len(fds), timeout)
   597	}
   598	
   599	// TODO: wrap
   600	//	Acct(name nil-string) (err error)
   601	//	Gethostuuid(uuid *byte, timeout *Timespec) (err error)
   602	//	Ptrace(req int, pid int, addr uintptr, data int) (ret uintptr, err error)
   603	
   604	var mapper = &mmapper{
   605		active: make(map[*byte][]byte),
   606		mmap:   mmap,
   607		munmap: munmap,
   608	}
   609	
   610	func Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) {
   611		return mapper.Mmap(fd, offset, length, prot, flags)
   612	}
   613	
   614	func Munmap(b []byte) (err error) {
   615		return mapper.Munmap(b)
   616	}
   617	
   618	//sys	Madvise(b []byte, behav int) (err error)
   619	//sys	Mlock(b []byte) (err error)
   620	//sys	Mlockall(flags int) (err error)
   621	//sys	Mprotect(b []byte, prot int) (err error)
   622	//sys	Msync(b []byte, flags int) (err error)
   623	//sys	Munlock(b []byte) (err error)
   624	//sys	Munlockall() (err error)
   625	

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