Source file src/pkg/syscall/syscall_linux.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	// Linux system calls.
     6	// This file is compiled as ordinary Go code,
     7	// but it is also input to mksyscall,
     8	// which parses the //sys lines and generates system call stubs.
     9	// Note that sometimes we use a lowercase //sys name and
    10	// wrap it in our own nicer implementation.
    11	
    12	package syscall
    13	
    14	import "unsafe"
    15	
    16	/*
    17	 * Wrapped
    18	 */
    19	
    20	//sys	open(path string, mode int, perm uint32) (fd int, err error)
    21	
    22	func Open(path string, mode int, perm uint32) (fd int, err error) {
    23		return open(path, mode|O_LARGEFILE, perm)
    24	}
    25	
    26	//sys	openat(dirfd int, path string, flags int, mode uint32) (fd int, err error)
    27	
    28	func Openat(dirfd int, path string, flags int, mode uint32) (fd int, err error) {
    29		return openat(dirfd, path, flags|O_LARGEFILE, mode)
    30	}
    31	
    32	//sysnb	pipe(p *[2]_C_int) (err error)
    33	
    34	func Pipe(p []int) (err error) {
    35		if len(p) != 2 {
    36			return EINVAL
    37		}
    38		var pp [2]_C_int
    39		err = pipe(&pp)
    40		p[0] = int(pp[0])
    41		p[1] = int(pp[1])
    42		return
    43	}
    44	
    45	//sysnb pipe2(p *[2]_C_int, flags int) (err error)
    46	
    47	func Pipe2(p []int, flags int) (err error) {
    48		if len(p) != 2 {
    49			return EINVAL
    50		}
    51		var pp [2]_C_int
    52		err = pipe2(&pp, flags)
    53		p[0] = int(pp[0])
    54		p[1] = int(pp[1])
    55		return
    56	}
    57	
    58	//sys	utimes(path string, times *[2]Timeval) (err error)
    59	
    60	func Utimes(path string, tv []Timeval) (err error) {
    61		if len(tv) != 2 {
    62			return EINVAL
    63		}
    64		return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
    65	}
    66	
    67	//sys	utimensat(dirfd int, path string, times *[2]Timespec) (err error)
    68	
    69	func UtimesNano(path string, ts []Timespec) (err error) {
    70		if len(ts) != 2 {
    71			return EINVAL
    72		}
    73		err = utimensat(_AT_FDCWD, path, (*[2]Timespec)(unsafe.Pointer(&ts[0])))
    74		if err != ENOSYS {
    75			return err
    76		}
    77		// If the utimensat syscall isn't available (utimensat was added to Linux
    78		// in 2.6.22, Released, 8 July 2007) then fall back to utimes
    79		var tv [2]Timeval
    80		for i := 0; i < 2; i++ {
    81			tv[i].Sec = ts[i].Sec
    82			tv[i].Usec = ts[i].Nsec / 1000
    83		}
    84		return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
    85	}
    86	
    87	//sys	futimesat(dirfd int, path *byte, times *[2]Timeval) (err error)
    88	
    89	func Futimesat(dirfd int, path string, tv []Timeval) (err error) {
    90		if len(tv) != 2 {
    91			return EINVAL
    92		}
    93		pathp, err := BytePtrFromString(path)
    94		if err != nil {
    95			return err
    96		}
    97		return futimesat(dirfd, pathp, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
    98	}
    99	
   100	func Futimes(fd int, tv []Timeval) (err error) {
   101		// Believe it or not, this is the best we can do on Linux
   102		// (and is what glibc does).
   103		return Utimes("/proc/self/fd/"+itoa(fd), tv)
   104	}
   105	
   106	const ImplementsGetwd = true
   107	
   108	//sys	Getcwd(buf []byte) (n int, err error)
   109	
   110	func Getwd() (wd string, err error) {
   111		var buf [PathMax]byte
   112		n, err := Getcwd(buf[0:])
   113		if err != nil {
   114			return "", err
   115		}
   116		// Getcwd returns the number of bytes written to buf, including the NUL.
   117		if n < 1 || n > len(buf) || buf[n-1] != 0 {
   118			return "", EINVAL
   119		}
   120		return string(buf[0 : n-1]), nil
   121	}
   122	
   123	func Getgroups() (gids []int, err error) {
   124		n, err := getgroups(0, nil)
   125		if err != nil {
   126			return nil, err
   127		}
   128		if n == 0 {
   129			return nil, nil
   130		}
   131	
   132		// Sanity check group count.  Max is 1<<16 on Linux.
   133		if n < 0 || n > 1<<20 {
   134			return nil, EINVAL
   135		}
   136	
   137		a := make([]_Gid_t, n)
   138		n, err = getgroups(n, &a[0])
   139		if err != nil {
   140			return nil, err
   141		}
   142		gids = make([]int, n)
   143		for i, v := range a[0:n] {
   144			gids[i] = int(v)
   145		}
   146		return
   147	}
   148	
   149	func Setgroups(gids []int) (err error) {
   150		if len(gids) == 0 {
   151			return setgroups(0, nil)
   152		}
   153	
   154		a := make([]_Gid_t, len(gids))
   155		for i, v := range gids {
   156			a[i] = _Gid_t(v)
   157		}
   158		return setgroups(len(a), &a[0])
   159	}
   160	
   161	type WaitStatus uint32
   162	
   163	// Wait status is 7 bits at bottom, either 0 (exited),
   164	// 0x7F (stopped), or a signal number that caused an exit.
   165	// The 0x80 bit is whether there was a core dump.
   166	// An extra number (exit code, signal causing a stop)
   167	// is in the high bits.  At least that's the idea.
   168	// There are various irregularities.  For example, the
   169	// "continued" status is 0xFFFF, distinguishing itself
   170	// from stopped via the core dump bit.
   171	
   172	const (
   173		mask    = 0x7F
   174		core    = 0x80
   175		exited  = 0x00
   176		stopped = 0x7F
   177		shift   = 8
   178	)
   179	
   180	func (w WaitStatus) Exited() bool { return w&mask == exited }
   181	
   182	func (w WaitStatus) Signaled() bool { return w&mask != stopped && w&mask != exited }
   183	
   184	func (w WaitStatus) Stopped() bool { return w&0xFF == stopped }
   185	
   186	func (w WaitStatus) Continued() bool { return w == 0xFFFF }
   187	
   188	func (w WaitStatus) CoreDump() bool { return w.Signaled() && w&core != 0 }
   189	
   190	func (w WaitStatus) ExitStatus() int {
   191		if !w.Exited() {
   192			return -1
   193		}
   194		return int(w>>shift) & 0xFF
   195	}
   196	
   197	func (w WaitStatus) Signal() Signal {
   198		if !w.Signaled() {
   199			return -1
   200		}
   201		return Signal(w & mask)
   202	}
   203	
   204	func (w WaitStatus) StopSignal() Signal {
   205		if !w.Stopped() {
   206			return -1
   207		}
   208		return Signal(w>>shift) & 0xFF
   209	}
   210	
   211	func (w WaitStatus) TrapCause() int {
   212		if w.StopSignal() != SIGTRAP {
   213			return -1
   214		}
   215		return int(w>>shift) >> 8
   216	}
   217	
   218	//sys	wait4(pid int, wstatus *_C_int, options int, rusage *Rusage) (wpid int, err error)
   219	
   220	func Wait4(pid int, wstatus *WaitStatus, options int, rusage *Rusage) (wpid int, err error) {
   221		var status _C_int
   222		wpid, err = wait4(pid, &status, options, rusage)
   223		if wstatus != nil {
   224			*wstatus = WaitStatus(status)
   225		}
   226		return
   227	}
   228	
   229	func Mkfifo(path string, mode uint32) (err error) {
   230		return Mknod(path, mode|S_IFIFO, 0)
   231	}
   232	
   233	// For testing: clients can set this flag to force
   234	// creation of IPv6 sockets to return EAFNOSUPPORT.
   235	var SocketDisableIPv6 bool
   236	
   237	type Sockaddr interface {
   238		sockaddr() (ptr uintptr, len _Socklen, err error) // lowercase; only we can define Sockaddrs
   239	}
   240	
   241	type SockaddrInet4 struct {
   242		Port int
   243		Addr [4]byte
   244		raw  RawSockaddrInet4
   245	}
   246	
   247	func (sa *SockaddrInet4) sockaddr() (uintptr, _Socklen, error) {
   248		if sa.Port < 0 || sa.Port > 0xFFFF {
   249			return 0, 0, EINVAL
   250		}
   251		sa.raw.Family = AF_INET
   252		p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port))
   253		p[0] = byte(sa.Port >> 8)
   254		p[1] = byte(sa.Port)
   255		for i := 0; i < len(sa.Addr); i++ {
   256			sa.raw.Addr[i] = sa.Addr[i]
   257		}
   258		return uintptr(unsafe.Pointer(&sa.raw)), SizeofSockaddrInet4, nil
   259	}
   260	
   261	type SockaddrInet6 struct {
   262		Port   int
   263		ZoneId uint32
   264		Addr   [16]byte
   265		raw    RawSockaddrInet6
   266	}
   267	
   268	func (sa *SockaddrInet6) sockaddr() (uintptr, _Socklen, error) {
   269		if sa.Port < 0 || sa.Port > 0xFFFF {
   270			return 0, 0, EINVAL
   271		}
   272		sa.raw.Family = AF_INET6
   273		p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port))
   274		p[0] = byte(sa.Port >> 8)
   275		p[1] = byte(sa.Port)
   276		sa.raw.Scope_id = sa.ZoneId
   277		for i := 0; i < len(sa.Addr); i++ {
   278			sa.raw.Addr[i] = sa.Addr[i]
   279		}
   280		return uintptr(unsafe.Pointer(&sa.raw)), SizeofSockaddrInet6, nil
   281	}
   282	
   283	type SockaddrUnix struct {
   284		Name string
   285		raw  RawSockaddrUnix
   286	}
   287	
   288	func (sa *SockaddrUnix) sockaddr() (uintptr, _Socklen, error) {
   289		name := sa.Name
   290		n := len(name)
   291		if n >= len(sa.raw.Path) {
   292			return 0, 0, EINVAL
   293		}
   294		sa.raw.Family = AF_UNIX
   295		for i := 0; i < n; i++ {
   296			sa.raw.Path[i] = int8(name[i])
   297		}
   298		// length is family (uint16), name, NUL.
   299		sl := _Socklen(2)
   300		if n > 0 {
   301			sl += _Socklen(n) + 1
   302		}
   303		if sa.raw.Path[0] == '@' {
   304			sa.raw.Path[0] = 0
   305			// Don't count trailing NUL for abstract address.
   306			sl--
   307		}
   308	
   309		return uintptr(unsafe.Pointer(&sa.raw)), sl, nil
   310	}
   311	
   312	type SockaddrLinklayer struct {
   313		Protocol uint16
   314		Ifindex  int
   315		Hatype   uint16
   316		Pkttype  uint8
   317		Halen    uint8
   318		Addr     [8]byte
   319		raw      RawSockaddrLinklayer
   320	}
   321	
   322	func (sa *SockaddrLinklayer) sockaddr() (uintptr, _Socklen, error) {
   323		if sa.Ifindex < 0 || sa.Ifindex > 0x7fffffff {
   324			return 0, 0, EINVAL
   325		}
   326		sa.raw.Family = AF_PACKET
   327		sa.raw.Protocol = sa.Protocol
   328		sa.raw.Ifindex = int32(sa.Ifindex)
   329		sa.raw.Hatype = sa.Hatype
   330		sa.raw.Pkttype = sa.Pkttype
   331		sa.raw.Halen = sa.Halen
   332		for i := 0; i < len(sa.Addr); i++ {
   333			sa.raw.Addr[i] = sa.Addr[i]
   334		}
   335		return uintptr(unsafe.Pointer(&sa.raw)), SizeofSockaddrLinklayer, nil
   336	}
   337	
   338	type SockaddrNetlink struct {
   339		Family uint16
   340		Pad    uint16
   341		Pid    uint32
   342		Groups uint32
   343		raw    RawSockaddrNetlink
   344	}
   345	
   346	func (sa *SockaddrNetlink) sockaddr() (uintptr, _Socklen, error) {
   347		sa.raw.Family = AF_NETLINK
   348		sa.raw.Pad = sa.Pad
   349		sa.raw.Pid = sa.Pid
   350		sa.raw.Groups = sa.Groups
   351		return uintptr(unsafe.Pointer(&sa.raw)), SizeofSockaddrNetlink, nil
   352	}
   353	
   354	func anyToSockaddr(rsa *RawSockaddrAny) (Sockaddr, error) {
   355		switch rsa.Addr.Family {
   356		case AF_NETLINK:
   357			pp := (*RawSockaddrNetlink)(unsafe.Pointer(rsa))
   358			sa := new(SockaddrNetlink)
   359			sa.Family = pp.Family
   360			sa.Pad = pp.Pad
   361			sa.Pid = pp.Pid
   362			sa.Groups = pp.Groups
   363			return sa, nil
   364	
   365		case AF_PACKET:
   366			pp := (*RawSockaddrLinklayer)(unsafe.Pointer(rsa))
   367			sa := new(SockaddrLinklayer)
   368			sa.Protocol = pp.Protocol
   369			sa.Ifindex = int(pp.Ifindex)
   370			sa.Hatype = pp.Hatype
   371			sa.Pkttype = pp.Pkttype
   372			sa.Halen = pp.Halen
   373			for i := 0; i < len(sa.Addr); i++ {
   374				sa.Addr[i] = pp.Addr[i]
   375			}
   376			return sa, nil
   377	
   378		case AF_UNIX:
   379			pp := (*RawSockaddrUnix)(unsafe.Pointer(rsa))
   380			sa := new(SockaddrUnix)
   381			if pp.Path[0] == 0 {
   382				// "Abstract" Unix domain socket.
   383				// Rewrite leading NUL as @ for textual display.
   384				// (This is the standard convention.)
   385				// Not friendly to overwrite in place,
   386				// but the callers below don't care.
   387				pp.Path[0] = '@'
   388			}
   389	
   390			// Assume path ends at NUL.
   391			// This is not technically the Linux semantics for
   392			// abstract Unix domain sockets--they are supposed
   393			// to be uninterpreted fixed-size binary blobs--but
   394			// everyone uses this convention.
   395			n := 0
   396			for n < len(pp.Path) && pp.Path[n] != 0 {
   397				n++
   398			}
   399			bytes := (*[10000]byte)(unsafe.Pointer(&pp.Path[0]))[0:n]
   400			sa.Name = string(bytes)
   401			return sa, nil
   402	
   403		case AF_INET:
   404			pp := (*RawSockaddrInet4)(unsafe.Pointer(rsa))
   405			sa := new(SockaddrInet4)
   406			p := (*[2]byte)(unsafe.Pointer(&pp.Port))
   407			sa.Port = int(p[0])<<8 + int(p[1])
   408			for i := 0; i < len(sa.Addr); i++ {
   409				sa.Addr[i] = pp.Addr[i]
   410			}
   411			return sa, nil
   412	
   413		case AF_INET6:
   414			pp := (*RawSockaddrInet6)(unsafe.Pointer(rsa))
   415			sa := new(SockaddrInet6)
   416			p := (*[2]byte)(unsafe.Pointer(&pp.Port))
   417			sa.Port = int(p[0])<<8 + int(p[1])
   418			sa.ZoneId = pp.Scope_id
   419			for i := 0; i < len(sa.Addr); i++ {
   420				sa.Addr[i] = pp.Addr[i]
   421			}
   422			return sa, nil
   423		}
   424		return nil, EAFNOSUPPORT
   425	}
   426	
   427	func Accept(fd int) (nfd int, sa Sockaddr, err error) {
   428		var rsa RawSockaddrAny
   429		var len _Socklen = SizeofSockaddrAny
   430		nfd, err = accept(fd, &rsa, &len)
   431		if err != nil {
   432			return
   433		}
   434		sa, err = anyToSockaddr(&rsa)
   435		if err != nil {
   436			Close(nfd)
   437			nfd = 0
   438		}
   439		return
   440	}
   441	
   442	func Accept4(fd int, flags int) (nfd int, sa Sockaddr, err error) {
   443		var rsa RawSockaddrAny
   444		var len _Socklen = SizeofSockaddrAny
   445		nfd, err = accept4(fd, &rsa, &len, flags)
   446		if err != nil {
   447			return
   448		}
   449		sa, err = anyToSockaddr(&rsa)
   450		if err != nil {
   451			Close(nfd)
   452			nfd = 0
   453		}
   454		return
   455	}
   456	
   457	func Getsockname(fd int) (sa Sockaddr, err error) {
   458		var rsa RawSockaddrAny
   459		var len _Socklen = SizeofSockaddrAny
   460		if err = getsockname(fd, &rsa, &len); err != nil {
   461			return
   462		}
   463		return anyToSockaddr(&rsa)
   464	}
   465	
   466	func Getpeername(fd int) (sa Sockaddr, err error) {
   467		var rsa RawSockaddrAny
   468		var len _Socklen = SizeofSockaddrAny
   469		if err = getpeername(fd, &rsa, &len); err != nil {
   470			return
   471		}
   472		return anyToSockaddr(&rsa)
   473	}
   474	
   475	func Bind(fd int, sa Sockaddr) (err error) {
   476		ptr, n, err := sa.sockaddr()
   477		if err != nil {
   478			return err
   479		}
   480		return bind(fd, ptr, n)
   481	}
   482	
   483	func Connect(fd int, sa Sockaddr) (err error) {
   484		ptr, n, err := sa.sockaddr()
   485		if err != nil {
   486			return err
   487		}
   488		return connect(fd, ptr, n)
   489	}
   490	
   491	func Socket(domain, typ, proto int) (fd int, err error) {
   492		if domain == AF_INET6 && SocketDisableIPv6 {
   493			return -1, EAFNOSUPPORT
   494		}
   495		fd, err = socket(domain, typ, proto)
   496		return
   497	}
   498	
   499	func Socketpair(domain, typ, proto int) (fd [2]int, err error) {
   500		var fdx [2]int32
   501		err = socketpair(domain, typ, proto, &fdx)
   502		if err == nil {
   503			fd[0] = int(fdx[0])
   504			fd[1] = int(fdx[1])
   505		}
   506		return
   507	}
   508	
   509	func GetsockoptInt(fd, level, opt int) (value int, err error) {
   510		var n int32
   511		vallen := _Socklen(4)
   512		err = getsockopt(fd, level, opt, uintptr(unsafe.Pointer(&n)), &vallen)
   513		return int(n), err
   514	}
   515	
   516	func GetsockoptInet4Addr(fd, level, opt int) (value [4]byte, err error) {
   517		vallen := _Socklen(4)
   518		err = getsockopt(fd, level, opt, uintptr(unsafe.Pointer(&value[0])), &vallen)
   519		return value, err
   520	}
   521	
   522	func GetsockoptIPMreq(fd, level, opt int) (*IPMreq, error) {
   523		var value IPMreq
   524		vallen := _Socklen(SizeofIPMreq)
   525		err := getsockopt(fd, level, opt, uintptr(unsafe.Pointer(&value)), &vallen)
   526		return &value, err
   527	}
   528	
   529	func GetsockoptIPMreqn(fd, level, opt int) (*IPMreqn, error) {
   530		var value IPMreqn
   531		vallen := _Socklen(SizeofIPMreqn)
   532		err := getsockopt(fd, level, opt, uintptr(unsafe.Pointer(&value)), &vallen)
   533		return &value, err
   534	}
   535	
   536	func GetsockoptIPv6Mreq(fd, level, opt int) (*IPv6Mreq, error) {
   537		var value IPv6Mreq
   538		vallen := _Socklen(SizeofIPv6Mreq)
   539		err := getsockopt(fd, level, opt, uintptr(unsafe.Pointer(&value)), &vallen)
   540		return &value, err
   541	}
   542	
   543	func GetsockoptUcred(fd, level, opt int) (*Ucred, error) {
   544		var value Ucred
   545		vallen := _Socklen(SizeofUcred)
   546		err := getsockopt(fd, level, opt, uintptr(unsafe.Pointer(&value)), &vallen)
   547		return &value, err
   548	}
   549	
   550	func SetsockoptInt(fd, level, opt int, value int) (err error) {
   551		var n = int32(value)
   552		return setsockopt(fd, level, opt, uintptr(unsafe.Pointer(&n)), 4)
   553	}
   554	
   555	func SetsockoptInet4Addr(fd, level, opt int, value [4]byte) (err error) {
   556		return setsockopt(fd, level, opt, uintptr(unsafe.Pointer(&value[0])), 4)
   557	}
   558	
   559	func SetsockoptTimeval(fd, level, opt int, tv *Timeval) (err error) {
   560		return setsockopt(fd, level, opt, uintptr(unsafe.Pointer(tv)), unsafe.Sizeof(*tv))
   561	}
   562	
   563	func SetsockoptLinger(fd, level, opt int, l *Linger) (err error) {
   564		return setsockopt(fd, level, opt, uintptr(unsafe.Pointer(l)), unsafe.Sizeof(*l))
   565	}
   566	
   567	func SetsockoptIPMreq(fd, level, opt int, mreq *IPMreq) (err error) {
   568		return setsockopt(fd, level, opt, uintptr(unsafe.Pointer(mreq)), unsafe.Sizeof(*mreq))
   569	}
   570	
   571	func SetsockoptIPMreqn(fd, level, opt int, mreq *IPMreqn) (err error) {
   572		return setsockopt(fd, level, opt, uintptr(unsafe.Pointer(mreq)), unsafe.Sizeof(*mreq))
   573	}
   574	
   575	func SetsockoptIPv6Mreq(fd, level, opt int, mreq *IPv6Mreq) (err error) {
   576		return setsockopt(fd, level, opt, uintptr(unsafe.Pointer(mreq)), unsafe.Sizeof(*mreq))
   577	}
   578	
   579	func SetsockoptString(fd, level, opt int, s string) (err error) {
   580		return setsockopt(fd, level, opt, uintptr(unsafe.Pointer(&[]byte(s)[0])), uintptr(len(s)))
   581	}
   582	
   583	func Recvfrom(fd int, p []byte, flags int) (n int, from Sockaddr, err error) {
   584		var rsa RawSockaddrAny
   585		var len _Socklen = SizeofSockaddrAny
   586		if n, err = recvfrom(fd, p, flags, &rsa, &len); err != nil {
   587			return
   588		}
   589		if rsa.Addr.Family != AF_UNSPEC {
   590			from, err = anyToSockaddr(&rsa)
   591		}
   592		return
   593	}
   594	
   595	func Sendto(fd int, p []byte, flags int, to Sockaddr) (err error) {
   596		ptr, n, err := to.sockaddr()
   597		if err != nil {
   598			return err
   599		}
   600		return sendto(fd, p, flags, ptr, n)
   601	}
   602	
   603	func Recvmsg(fd int, p, oob []byte, flags int) (n, oobn int, recvflags int, from Sockaddr, err error) {
   604		var msg Msghdr
   605		var rsa RawSockaddrAny
   606		msg.Name = (*byte)(unsafe.Pointer(&rsa))
   607		msg.Namelen = uint32(SizeofSockaddrAny)
   608		var iov Iovec
   609		if len(p) > 0 {
   610			iov.Base = (*byte)(unsafe.Pointer(&p[0]))
   611			iov.SetLen(len(p))
   612		}
   613		var dummy byte
   614		if len(oob) > 0 {
   615			// receive at least one normal byte
   616			if len(p) == 0 {
   617				iov.Base = &dummy
   618				iov.SetLen(1)
   619			}
   620			msg.Control = (*byte)(unsafe.Pointer(&oob[0]))
   621			msg.SetControllen(len(oob))
   622		}
   623		msg.Iov = &iov
   624		msg.Iovlen = 1
   625		if n, err = recvmsg(fd, &msg, flags); err != nil {
   626			return
   627		}
   628		oobn = int(msg.Controllen)
   629		recvflags = int(msg.Flags)
   630		// source address is only specified if the socket is unconnected
   631		if rsa.Addr.Family != AF_UNSPEC {
   632			from, err = anyToSockaddr(&rsa)
   633		}
   634		return
   635	}
   636	
   637	func Sendmsg(fd int, p, oob []byte, to Sockaddr, flags int) (err error) {
   638		var ptr uintptr
   639		var salen _Socklen
   640		if to != nil {
   641			var err error
   642			ptr, salen, err = to.sockaddr()
   643			if err != nil {
   644				return err
   645			}
   646		}
   647		var msg Msghdr
   648		msg.Name = (*byte)(unsafe.Pointer(ptr))
   649		msg.Namelen = uint32(salen)
   650		var iov Iovec
   651		if len(p) > 0 {
   652			iov.Base = (*byte)(unsafe.Pointer(&p[0]))
   653			iov.SetLen(len(p))
   654		}
   655		var dummy byte
   656		if len(oob) > 0 {
   657			// send at least one normal byte
   658			if len(p) == 0 {
   659				iov.Base = &dummy
   660				iov.SetLen(1)
   661			}
   662			msg.Control = (*byte)(unsafe.Pointer(&oob[0]))
   663			msg.SetControllen(len(oob))
   664		}
   665		msg.Iov = &iov
   666		msg.Iovlen = 1
   667		if err = sendmsg(fd, &msg, flags); err != nil {
   668			return
   669		}
   670		return
   671	}
   672	
   673	// BindToDevice binds the socket associated with fd to device.
   674	func BindToDevice(fd int, device string) (err error) {
   675		return SetsockoptString(fd, SOL_SOCKET, SO_BINDTODEVICE, device)
   676	}
   677	
   678	//sys	ptrace(request int, pid int, addr uintptr, data uintptr) (err error)
   679	
   680	func ptracePeek(req int, pid int, addr uintptr, out []byte) (count int, err error) {
   681		// The peek requests are machine-size oriented, so we wrap it
   682		// to retrieve arbitrary-length data.
   683	
   684		// The ptrace syscall differs from glibc's ptrace.
   685		// Peeks returns the word in *data, not as the return value.
   686	
   687		var buf [sizeofPtr]byte
   688	
   689		// Leading edge.  PEEKTEXT/PEEKDATA don't require aligned
   690		// access (PEEKUSER warns that it might), but if we don't
   691		// align our reads, we might straddle an unmapped page
   692		// boundary and not get the bytes leading up to the page
   693		// boundary.
   694		n := 0
   695		if addr%sizeofPtr != 0 {
   696			err = ptrace(req, pid, addr-addr%sizeofPtr, uintptr(unsafe.Pointer(&buf[0])))
   697			if err != nil {
   698				return 0, err
   699			}
   700			n += copy(out, buf[addr%sizeofPtr:])
   701			out = out[n:]
   702		}
   703	
   704		// Remainder.
   705		for len(out) > 0 {
   706			// We use an internal buffer to guarantee alignment.
   707			// It's not documented if this is necessary, but we're paranoid.
   708			err = ptrace(req, pid, addr+uintptr(n), uintptr(unsafe.Pointer(&buf[0])))
   709			if err != nil {
   710				return n, err
   711			}
   712			copied := copy(out, buf[0:])
   713			n += copied
   714			out = out[copied:]
   715		}
   716	
   717		return n, nil
   718	}
   719	
   720	func PtracePeekText(pid int, addr uintptr, out []byte) (count int, err error) {
   721		return ptracePeek(PTRACE_PEEKTEXT, pid, addr, out)
   722	}
   723	
   724	func PtracePeekData(pid int, addr uintptr, out []byte) (count int, err error) {
   725		return ptracePeek(PTRACE_PEEKDATA, pid, addr, out)
   726	}
   727	
   728	func ptracePoke(pokeReq int, peekReq int, pid int, addr uintptr, data []byte) (count int, err error) {
   729		// As for ptracePeek, we need to align our accesses to deal
   730		// with the possibility of straddling an invalid page.
   731	
   732		// Leading edge.
   733		n := 0
   734		if addr%sizeofPtr != 0 {
   735			var buf [sizeofPtr]byte
   736			err = ptrace(peekReq, pid, addr-addr%sizeofPtr, uintptr(unsafe.Pointer(&buf[0])))
   737			if err != nil {
   738				return 0, err
   739			}
   740			n += copy(buf[addr%sizeofPtr:], data)
   741			word := *((*uintptr)(unsafe.Pointer(&buf[0])))
   742			err = ptrace(pokeReq, pid, addr-addr%sizeofPtr, word)
   743			if err != nil {
   744				return 0, err
   745			}
   746			data = data[n:]
   747		}
   748	
   749		// Interior.
   750		for len(data) > sizeofPtr {
   751			word := *((*uintptr)(unsafe.Pointer(&data[0])))
   752			err = ptrace(pokeReq, pid, addr+uintptr(n), word)
   753			if err != nil {
   754				return n, err
   755			}
   756			n += sizeofPtr
   757			data = data[sizeofPtr:]
   758		}
   759	
   760		// Trailing edge.
   761		if len(data) > 0 {
   762			var buf [sizeofPtr]byte
   763			err = ptrace(peekReq, pid, addr+uintptr(n), uintptr(unsafe.Pointer(&buf[0])))
   764			if err != nil {
   765				return n, err
   766			}
   767			copy(buf[0:], data)
   768			word := *((*uintptr)(unsafe.Pointer(&buf[0])))
   769			err = ptrace(pokeReq, pid, addr+uintptr(n), word)
   770			if err != nil {
   771				return n, err
   772			}
   773			n += len(data)
   774		}
   775	
   776		return n, nil
   777	}
   778	
   779	func PtracePokeText(pid int, addr uintptr, data []byte) (count int, err error) {
   780		return ptracePoke(PTRACE_POKETEXT, PTRACE_PEEKTEXT, pid, addr, data)
   781	}
   782	
   783	func PtracePokeData(pid int, addr uintptr, data []byte) (count int, err error) {
   784		return ptracePoke(PTRACE_POKEDATA, PTRACE_PEEKDATA, pid, addr, data)
   785	}
   786	
   787	func PtraceGetRegs(pid int, regsout *PtraceRegs) (err error) {
   788		return ptrace(PTRACE_GETREGS, pid, 0, uintptr(unsafe.Pointer(regsout)))
   789	}
   790	
   791	func PtraceSetRegs(pid int, regs *PtraceRegs) (err error) {
   792		return ptrace(PTRACE_SETREGS, pid, 0, uintptr(unsafe.Pointer(regs)))
   793	}
   794	
   795	func PtraceSetOptions(pid int, options int) (err error) {
   796		return ptrace(PTRACE_SETOPTIONS, pid, 0, uintptr(options))
   797	}
   798	
   799	func PtraceGetEventMsg(pid int) (msg uint, err error) {
   800		var data _C_long
   801		err = ptrace(PTRACE_GETEVENTMSG, pid, 0, uintptr(unsafe.Pointer(&data)))
   802		msg = uint(data)
   803		return
   804	}
   805	
   806	func PtraceCont(pid int, signal int) (err error) {
   807		return ptrace(PTRACE_CONT, pid, 0, uintptr(signal))
   808	}
   809	
   810	func PtraceSyscall(pid int, signal int) (err error) {
   811		return ptrace(PTRACE_SYSCALL, pid, 0, uintptr(signal))
   812	}
   813	
   814	func PtraceSingleStep(pid int) (err error) { return ptrace(PTRACE_SINGLESTEP, pid, 0, 0) }
   815	
   816	func PtraceAttach(pid int) (err error) { return ptrace(PTRACE_ATTACH, pid, 0, 0) }
   817	
   818	func PtraceDetach(pid int) (err error) { return ptrace(PTRACE_DETACH, pid, 0, 0) }
   819	
   820	//sys	reboot(magic1 uint, magic2 uint, cmd int, arg string) (err error)
   821	
   822	func Reboot(cmd int) (err error) {
   823		return reboot(LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, cmd, "")
   824	}
   825	
   826	func clen(n []byte) int {
   827		for i := 0; i < len(n); i++ {
   828			if n[i] == 0 {
   829				return i
   830			}
   831		}
   832		return len(n)
   833	}
   834	
   835	func ReadDirent(fd int, buf []byte) (n int, err error) {
   836		return Getdents(fd, buf)
   837	}
   838	
   839	func ParseDirent(buf []byte, max int, names []string) (consumed int, count int, newnames []string) {
   840		origlen := len(buf)
   841		count = 0
   842		for max != 0 && len(buf) > 0 {
   843			dirent := (*Dirent)(unsafe.Pointer(&buf[0]))
   844			buf = buf[dirent.Reclen:]
   845			if dirent.Ino == 0 { // File absent in directory.
   846				continue
   847			}
   848			bytes := (*[10000]byte)(unsafe.Pointer(&dirent.Name[0]))
   849			var name = string(bytes[0:clen(bytes[:])])
   850			if name == "." || name == ".." { // Useless names
   851				continue
   852			}
   853			max--
   854			count++
   855			names = append(names, name)
   856		}
   857		return origlen - len(buf), count, names
   858	}
   859	
   860	//sys	mount(source string, target string, fstype string, flags uintptr, data *byte) (err error)
   861	
   862	func Mount(source string, target string, fstype string, flags uintptr, data string) (err error) {
   863		// Certain file systems get rather angry and EINVAL if you give
   864		// them an empty string of data, rather than NULL.
   865		if data == "" {
   866			return mount(source, target, fstype, flags, nil)
   867		}
   868		datap, err := BytePtrFromString(data)
   869		if err != nil {
   870			return err
   871		}
   872		return mount(source, target, fstype, flags, datap)
   873	}
   874	
   875	// Sendto
   876	// Recvfrom
   877	// Socketpair
   878	
   879	/*
   880	 * Direct access
   881	 */
   882	//sys	Access(path string, mode uint32) (err error)
   883	//sys	Acct(path string) (err error)
   884	//sys	Adjtimex(buf *Timex) (state int, err error)
   885	//sys	Chdir(path string) (err error)
   886	//sys	Chmod(path string, mode uint32) (err error)
   887	//sys	Chroot(path string) (err error)
   888	//sys	Close(fd int) (err error)
   889	//sys	Creat(path string, mode uint32) (fd int, err error)
   890	//sysnb	Dup(oldfd int) (fd int, err error)
   891	//sysnb	Dup2(oldfd int, newfd int) (err error)
   892	//sysnb	EpollCreate(size int) (fd int, err error)
   893	//sysnb	EpollCreate1(flag int) (fd int, err error)
   894	//sysnb	EpollCtl(epfd int, op int, fd int, event *EpollEvent) (err error)
   895	//sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
   896	//sys	Exit(code int) = SYS_EXIT_GROUP
   897	//sys	Faccessat(dirfd int, path string, mode uint32, flags int) (err error)
   898	//sys	Fallocate(fd int, mode uint32, off int64, len int64) (err error)
   899	//sys	Fchdir(fd int) (err error)
   900	//sys	Fchmod(fd int, mode uint32) (err error)
   901	//sys	Fchmodat(dirfd int, path string, mode uint32, flags int) (err error)
   902	//sys	Fchownat(dirfd int, path string, uid int, gid int, flags int) (err error)
   903	//sys	fcntl(fd int, cmd int, arg int) (val int, err error)
   904	//sys	Fdatasync(fd int) (err error)
   905	//sys	Flock(fd int, how int) (err error)
   906	//sys	Fsync(fd int) (err error)
   907	//sys	Getdents(fd int, buf []byte) (n int, err error) = SYS_GETDENTS64
   908	//sysnb	Getpgid(pid int) (pgid int, err error)
   909	//sysnb	Getpgrp() (pid int)
   910	//sysnb	Getpid() (pid int)
   911	//sysnb	Getppid() (ppid int)
   912	//sysnb	Getrusage(who int, rusage *Rusage) (err error)
   913	//sysnb	Gettid() (tid int)
   914	//sys	Getxattr(path string, attr string, dest []byte) (sz int, err error)
   915	//sys	InotifyAddWatch(fd int, pathname string, mask uint32) (watchdesc int, err error)
   916	//sysnb	InotifyInit() (fd int, err error)
   917	//sysnb	InotifyInit1(flags int) (fd int, err error)
   918	//sysnb	InotifyRmWatch(fd int, watchdesc uint32) (success int, err error)
   919	//sysnb	Kill(pid int, sig Signal) (err error)
   920	//sys	Klogctl(typ int, buf []byte) (n int, err error) = SYS_SYSLOG
   921	//sys	Link(oldpath string, newpath string) (err error)
   922	//sys	Listxattr(path string, dest []byte) (sz int, err error)
   923	//sys	Mkdir(path string, mode uint32) (err error)
   924	//sys	Mkdirat(dirfd int, path string, mode uint32) (err error)
   925	//sys	Mknod(path string, mode uint32, dev int) (err error)
   926	//sys	Mknodat(dirfd int, path string, mode uint32, dev int) (err error)
   927	//sys	Nanosleep(time *Timespec, leftover *Timespec) (err error)
   928	//sys	Pause() (err error)
   929	//sys	PivotRoot(newroot string, putold string) (err error) = SYS_PIVOT_ROOT
   930	//sysnb prlimit(pid int, resource int, old *Rlimit, newlimit *Rlimit) (err error) = SYS_PRLIMIT64
   931	//sys	read(fd int, p []byte) (n int, err error)
   932	//sys	Readlink(path string, buf []byte) (n int, err error)
   933	//sys	Removexattr(path string, attr string) (err error)
   934	//sys	Rename(oldpath string, newpath string) (err error)
   935	//sys	Renameat(olddirfd int, oldpath string, newdirfd int, newpath string) (err error)
   936	//sys	Rmdir(path string) (err error)
   937	//sys	Setdomainname(p []byte) (err error)
   938	//sys	Sethostname(p []byte) (err error)
   939	//sysnb	Setpgid(pid int, pgid int) (err error)
   940	//sysnb	Setsid() (pid int, err error)
   941	//sysnb	Settimeofday(tv *Timeval) (err error)
   942	//sysnb	Setuid(uid int) (err error)
   943	//sys	Setxattr(path string, attr string, data []byte, flags int) (err error)
   944	//sys	Symlink(oldpath string, newpath string) (err error)
   945	//sys	Sync()
   946	//sysnb	Sysinfo(info *Sysinfo_t) (err error)
   947	//sys	Tee(rfd int, wfd int, len int, flags int) (n int64, err error)
   948	//sysnb	Tgkill(tgid int, tid int, sig Signal) (err error)
   949	//sysnb	Times(tms *Tms) (ticks uintptr, err error)
   950	//sysnb	Umask(mask int) (oldmask int)
   951	//sysnb	Uname(buf *Utsname) (err error)
   952	//sys	Unlink(path string) (err error)
   953	//sys	Unlinkat(dirfd int, path string) (err error)
   954	//sys	Unmount(target string, flags int) (err error) = SYS_UMOUNT2
   955	//sys	Unshare(flags int) (err error)
   956	//sys	Ustat(dev int, ubuf *Ustat_t) (err error)
   957	//sys	Utime(path string, buf *Utimbuf) (err error)
   958	//sys	write(fd int, p []byte) (n int, err error)
   959	//sys	exitThread(code int) (err error) = SYS_EXIT
   960	//sys	readlen(fd int, p *byte, np int) (n int, err error) = SYS_READ
   961	//sys	writelen(fd int, p *byte, np int) (n int, err error) = SYS_WRITE
   962	
   963	// mmap varies by architecture; see syscall_linux_*.go.
   964	//sys	munmap(addr uintptr, length uintptr) (err error)
   965	
   966	var mapper = &mmapper{
   967		active: make(map[*byte][]byte),
   968		mmap:   mmap,
   969		munmap: munmap,
   970	}
   971	
   972	func Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) {
   973		return mapper.Mmap(fd, offset, length, prot, flags)
   974	}
   975	
   976	func Munmap(b []byte) (err error) {
   977		return mapper.Munmap(b)
   978	}
   979	
   980	//sys	Madvise(b []byte, advice int) (err error)
   981	//sys	Mprotect(b []byte, prot int) (err error)
   982	//sys	Mlock(b []byte) (err error)
   983	//sys	Munlock(b []byte) (err error)
   984	//sys	Mlockall(flags int) (err error)
   985	//sys	Munlockall() (err error)
   986	
   987	/*
   988	 * Unimplemented
   989	 */
   990	// AddKey
   991	// AfsSyscall
   992	// Alarm
   993	// ArchPrctl
   994	// Brk
   995	// Capget
   996	// Capset
   997	// ClockGetres
   998	// ClockGettime
   999	// ClockNanosleep
  1000	// ClockSettime
  1001	// Clone
  1002	// CreateModule
  1003	// DeleteModule
  1004	// EpollCtlOld
  1005	// EpollPwait
  1006	// EpollWaitOld
  1007	// Eventfd
  1008	// Execve
  1009	// Fadvise64
  1010	// Fgetxattr
  1011	// Flistxattr
  1012	// Fork
  1013	// Fremovexattr
  1014	// Fsetxattr
  1015	// Futex
  1016	// GetKernelSyms
  1017	// GetMempolicy
  1018	// GetRobustList
  1019	// GetThreadArea
  1020	// Getitimer
  1021	// Getpmsg
  1022	// Getpriority
  1023	// IoCancel
  1024	// IoDestroy
  1025	// IoGetevents
  1026	// IoSetup
  1027	// IoSubmit
  1028	// Ioctl
  1029	// IoprioGet
  1030	// IoprioSet
  1031	// KexecLoad
  1032	// Keyctl
  1033	// Lgetxattr
  1034	// Llistxattr
  1035	// LookupDcookie
  1036	// Lremovexattr
  1037	// Lsetxattr
  1038	// Mbind
  1039	// MigratePages
  1040	// Mincore
  1041	// ModifyLdt
  1042	// Mount
  1043	// MovePages
  1044	// Mprotect
  1045	// MqGetsetattr
  1046	// MqNotify
  1047	// MqOpen
  1048	// MqTimedreceive
  1049	// MqTimedsend
  1050	// MqUnlink
  1051	// Mremap
  1052	// Msgctl
  1053	// Msgget
  1054	// Msgrcv
  1055	// Msgsnd
  1056	// Msync
  1057	// Newfstatat
  1058	// Nfsservctl
  1059	// Personality
  1060	// Poll
  1061	// Ppoll
  1062	// Prctl
  1063	// Pselect6
  1064	// Ptrace
  1065	// Putpmsg
  1066	// QueryModule
  1067	// Quotactl
  1068	// Readahead
  1069	// Readv
  1070	// RemapFilePages
  1071	// RequestKey
  1072	// RestartSyscall
  1073	// RtSigaction
  1074	// RtSigpending
  1075	// RtSigprocmask
  1076	// RtSigqueueinfo
  1077	// RtSigreturn
  1078	// RtSigsuspend
  1079	// RtSigtimedwait
  1080	// SchedGetPriorityMax
  1081	// SchedGetPriorityMin
  1082	// SchedGetaffinity
  1083	// SchedGetparam
  1084	// SchedGetscheduler
  1085	// SchedRrGetInterval
  1086	// SchedSetaffinity
  1087	// SchedSetparam
  1088	// SchedYield
  1089	// Security
  1090	// Semctl
  1091	// Semget
  1092	// Semop
  1093	// Semtimedop
  1094	// SetMempolicy
  1095	// SetRobustList
  1096	// SetThreadArea
  1097	// SetTidAddress
  1098	// Setpriority
  1099	// Shmat
  1100	// Shmctl
  1101	// Shmdt
  1102	// Shmget
  1103	// Sigaltstack
  1104	// Signalfd
  1105	// Swapoff
  1106	// Swapon
  1107	// Sysfs
  1108	// TimerCreate
  1109	// TimerDelete
  1110	// TimerGetoverrun
  1111	// TimerGettime
  1112	// TimerSettime
  1113	// Timerfd
  1114	// Tkill (obsolete)
  1115	// Tuxcall
  1116	// Umount2
  1117	// Uselib
  1118	// Utimensat
  1119	// Vfork
  1120	// Vhangup
  1121	// Vmsplice
  1122	// Vserver
  1123	// Waitid
  1124	// _Sysctl

View as plain text