syscall_darwin.go raw

   1  // Copyright 2009,2010 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  // Darwin 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 wrap
  10  // it in our own nicer implementation, either here or in
  11  // syscall_bsd.go or syscall_unix.go.
  12  
  13  package unix
  14  
  15  import (
  16  	"fmt"
  17  	"syscall"
  18  	"unsafe"
  19  )
  20  
  21  //sys	closedir(dir uintptr) (err error)
  22  //sys	readdir_r(dir uintptr, entry *Dirent, result **Dirent) (res Errno)
  23  
  24  func fdopendir(fd int) (dir uintptr, err error) {
  25  	r0, _, e1 := syscall_syscallPtr(libc_fdopendir_trampoline_addr, uintptr(fd), 0, 0)
  26  	dir = uintptr(r0)
  27  	if e1 != 0 {
  28  		err = errnoErr(e1)
  29  	}
  30  	return
  31  }
  32  
  33  var libc_fdopendir_trampoline_addr uintptr
  34  
  35  //go:cgo_import_dynamic libc_fdopendir fdopendir "/usr/lib/libSystem.B.dylib"
  36  
  37  func Getdirentries(fd int, buf []byte, basep *uintptr) (n int, err error) {
  38  	// Simulate Getdirentries using fdopendir/readdir_r/closedir.
  39  	// We store the number of entries to skip in the seek
  40  	// offset of fd. See issue #31368.
  41  	// It's not the full required semantics, but should handle the case
  42  	// of calling Getdirentries or ReadDirent repeatedly.
  43  	// It won't handle assigning the results of lseek to *basep, or handle
  44  	// the directory being edited underfoot.
  45  	skip, err := Seek(fd, 0, 1 /* SEEK_CUR */)
  46  	if err != nil {
  47  		return 0, err
  48  	}
  49  
  50  	// We need to duplicate the incoming file descriptor
  51  	// because the caller expects to retain control of it, but
  52  	// fdopendir expects to take control of its argument.
  53  	// Just Dup'ing the file descriptor is not enough, as the
  54  	// result shares underlying state. Use Openat to make a really
  55  	// new file descriptor referring to the same directory.
  56  	fd2, err := Openat(fd, ".", O_RDONLY, 0)
  57  	if err != nil {
  58  		return 0, err
  59  	}
  60  	d, err := fdopendir(fd2)
  61  	if err != nil {
  62  		Close(fd2)
  63  		return 0, err
  64  	}
  65  	defer closedir(d)
  66  
  67  	var cnt int64
  68  	for {
  69  		var entry Dirent
  70  		var entryp *Dirent
  71  		e := readdir_r(d, &entry, &entryp)
  72  		if e != 0 {
  73  			return n, errnoErr(e)
  74  		}
  75  		if entryp == nil {
  76  			break
  77  		}
  78  		if skip > 0 {
  79  			skip--
  80  			cnt++
  81  			continue
  82  		}
  83  
  84  		reclen := int(entry.Reclen)
  85  		if reclen > len(buf) {
  86  			// Not enough room. Return for now.
  87  			// The counter will let us know where we should start up again.
  88  			// Note: this strategy for suspending in the middle and
  89  			// restarting is O(n^2) in the length of the directory. Oh well.
  90  			break
  91  		}
  92  
  93  		// Copy entry into return buffer.
  94  		s := unsafe.Slice((*byte)(unsafe.Pointer(&entry)), reclen)
  95  		copy(buf, s)
  96  
  97  		buf = buf[reclen:]
  98  		n += reclen
  99  		cnt++
 100  	}
 101  	// Set the seek offset of the input fd to record
 102  	// how many files we've already returned.
 103  	_, err = Seek(fd, cnt, 0 /* SEEK_SET */)
 104  	if err != nil {
 105  		return n, err
 106  	}
 107  
 108  	return n, nil
 109  }
 110  
 111  // SockaddrDatalink implements the Sockaddr interface for AF_LINK type sockets.
 112  type SockaddrDatalink struct {
 113  	Len    uint8
 114  	Family uint8
 115  	Index  uint16
 116  	Type   uint8
 117  	Nlen   uint8
 118  	Alen   uint8
 119  	Slen   uint8
 120  	Data   [12]int8
 121  	raw    RawSockaddrDatalink
 122  }
 123  
 124  // SockaddrCtl implements the Sockaddr interface for AF_SYSTEM type sockets.
 125  type SockaddrCtl struct {
 126  	ID   uint32
 127  	Unit uint32
 128  	raw  RawSockaddrCtl
 129  }
 130  
 131  func (sa *SockaddrCtl) sockaddr() (unsafe.Pointer, _Socklen, error) {
 132  	sa.raw.Sc_len = SizeofSockaddrCtl
 133  	sa.raw.Sc_family = AF_SYSTEM
 134  	sa.raw.Ss_sysaddr = AF_SYS_CONTROL
 135  	sa.raw.Sc_id = sa.ID
 136  	sa.raw.Sc_unit = sa.Unit
 137  	return unsafe.Pointer(&sa.raw), SizeofSockaddrCtl, nil
 138  }
 139  
 140  // SockaddrVM implements the Sockaddr interface for AF_VSOCK type sockets.
 141  // SockaddrVM provides access to Darwin VM sockets: a mechanism that enables
 142  // bidirectional communication between a hypervisor and its guest virtual
 143  // machines.
 144  type SockaddrVM struct {
 145  	// CID and Port specify a context ID and port address for a VM socket.
 146  	// Guests have a unique CID, and hosts may have a well-known CID of:
 147  	//  - VMADDR_CID_HYPERVISOR: refers to the hypervisor process.
 148  	//  - VMADDR_CID_LOCAL: refers to local communication (loopback).
 149  	//  - VMADDR_CID_HOST: refers to other processes on the host.
 150  	CID  uint32
 151  	Port uint32
 152  	raw  RawSockaddrVM
 153  }
 154  
 155  func (sa *SockaddrVM) sockaddr() (unsafe.Pointer, _Socklen, error) {
 156  	sa.raw.Len = SizeofSockaddrVM
 157  	sa.raw.Family = AF_VSOCK
 158  	sa.raw.Port = sa.Port
 159  	sa.raw.Cid = sa.CID
 160  
 161  	return unsafe.Pointer(&sa.raw), SizeofSockaddrVM, nil
 162  }
 163  
 164  func anyToSockaddrGOOS(fd int, rsa *RawSockaddrAny) (Sockaddr, error) {
 165  	switch rsa.Addr.Family {
 166  	case AF_SYSTEM:
 167  		pp := (*RawSockaddrCtl)(unsafe.Pointer(rsa))
 168  		if pp.Ss_sysaddr == AF_SYS_CONTROL {
 169  			sa := new(SockaddrCtl)
 170  			sa.ID = pp.Sc_id
 171  			sa.Unit = pp.Sc_unit
 172  			return sa, nil
 173  		}
 174  	case AF_VSOCK:
 175  		pp := (*RawSockaddrVM)(unsafe.Pointer(rsa))
 176  		sa := &SockaddrVM{
 177  			CID:  pp.Cid,
 178  			Port: pp.Port,
 179  		}
 180  		return sa, nil
 181  	}
 182  	return nil, EAFNOSUPPORT
 183  }
 184  
 185  // Some external packages rely on SYS___SYSCTL being defined to implement their
 186  // own sysctl wrappers. Provide it here, even though direct syscalls are no
 187  // longer supported on darwin.
 188  const SYS___SYSCTL = SYS_SYSCTL
 189  
 190  // Translate "kern.hostname" to []_C_int{0,1,2,3}.
 191  func nametomib(name string) (mib []_C_int, err error) {
 192  	const siz = unsafe.Sizeof(mib[0])
 193  
 194  	// NOTE(rsc): It seems strange to set the buffer to have
 195  	// size CTL_MAXNAME+2 but use only CTL_MAXNAME
 196  	// as the size. I don't know why the +2 is here, but the
 197  	// kernel uses +2 for its own implementation of this function.
 198  	// I am scared that if we don't include the +2 here, the kernel
 199  	// will silently write 2 words farther than we specify
 200  	// and we'll get memory corruption.
 201  	var buf [CTL_MAXNAME + 2]_C_int
 202  	n := uintptr(CTL_MAXNAME) * siz
 203  
 204  	p := (*byte)(unsafe.Pointer(&buf[0]))
 205  	bytes, err := ByteSliceFromString(name)
 206  	if err != nil {
 207  		return nil, err
 208  	}
 209  
 210  	// Magic sysctl: "setting" 0.3 to a string name
 211  	// lets you read back the array of integers form.
 212  	if err = sysctl([]_C_int{0, 3}, p, &n, &bytes[0], uintptr(len(name))); err != nil {
 213  		return nil, err
 214  	}
 215  	return buf[0 : n/siz], nil
 216  }
 217  
 218  func direntIno(buf []byte) (uint64, bool) {
 219  	return readInt(buf, unsafe.Offsetof(Dirent{}.Ino), unsafe.Sizeof(Dirent{}.Ino))
 220  }
 221  
 222  func direntReclen(buf []byte) (uint64, bool) {
 223  	return readInt(buf, unsafe.Offsetof(Dirent{}.Reclen), unsafe.Sizeof(Dirent{}.Reclen))
 224  }
 225  
 226  func direntNamlen(buf []byte) (uint64, bool) {
 227  	return readInt(buf, unsafe.Offsetof(Dirent{}.Namlen), unsafe.Sizeof(Dirent{}.Namlen))
 228  }
 229  
 230  func PtraceAttach(pid int) (err error) { return ptrace(PT_ATTACH, pid, 0, 0) }
 231  func PtraceDetach(pid int) (err error) { return ptrace(PT_DETACH, pid, 0, 0) }
 232  func PtraceDenyAttach() (err error)    { return ptrace(PT_DENY_ATTACH, 0, 0, 0) }
 233  
 234  //sysnb	pipe(p *[2]int32) (err error)
 235  
 236  func Pipe(p []int) (err error) {
 237  	if len(p) != 2 {
 238  		return EINVAL
 239  	}
 240  	var x [2]int32
 241  	err = pipe(&x)
 242  	if err == nil {
 243  		p[0] = int(x[0])
 244  		p[1] = int(x[1])
 245  	}
 246  	return
 247  }
 248  
 249  func Getfsstat(buf []Statfs_t, flags int) (n int, err error) {
 250  	var _p0 unsafe.Pointer
 251  	var bufsize uintptr
 252  	if len(buf) > 0 {
 253  		_p0 = unsafe.Pointer(&buf[0])
 254  		bufsize = unsafe.Sizeof(Statfs_t{}) * uintptr(len(buf))
 255  	}
 256  	return getfsstat(_p0, bufsize, flags)
 257  }
 258  
 259  func xattrPointer(dest []byte) *byte {
 260  	// It's only when dest is set to NULL that the OS X implementations of
 261  	// getxattr() and listxattr() return the current sizes of the named attributes.
 262  	// An empty byte array is not sufficient. To maintain the same behaviour as the
 263  	// linux implementation, we wrap around the system calls and pass in NULL when
 264  	// dest is empty.
 265  	var destp *byte
 266  	if len(dest) > 0 {
 267  		destp = &dest[0]
 268  	}
 269  	return destp
 270  }
 271  
 272  //sys	getxattr(path string, attr string, dest *byte, size int, position uint32, options int) (sz int, err error)
 273  
 274  func Getxattr(path string, attr string, dest []byte) (sz int, err error) {
 275  	return getxattr(path, attr, xattrPointer(dest), len(dest), 0, 0)
 276  }
 277  
 278  func Lgetxattr(link string, attr string, dest []byte) (sz int, err error) {
 279  	return getxattr(link, attr, xattrPointer(dest), len(dest), 0, XATTR_NOFOLLOW)
 280  }
 281  
 282  //sys	fgetxattr(fd int, attr string, dest *byte, size int, position uint32, options int) (sz int, err error)
 283  
 284  func Fgetxattr(fd int, attr string, dest []byte) (sz int, err error) {
 285  	return fgetxattr(fd, attr, xattrPointer(dest), len(dest), 0, 0)
 286  }
 287  
 288  //sys	setxattr(path string, attr string, data *byte, size int, position uint32, options int) (err error)
 289  
 290  func Setxattr(path string, attr string, data []byte, flags int) (err error) {
 291  	// The parameters for the OS X implementation vary slightly compared to the
 292  	// linux system call, specifically the position parameter:
 293  	//
 294  	//  linux:
 295  	//      int setxattr(
 296  	//          const char *path,
 297  	//          const char *name,
 298  	//          const void *value,
 299  	//          size_t size,
 300  	//          int flags
 301  	//      );
 302  	//
 303  	//  darwin:
 304  	//      int setxattr(
 305  	//          const char *path,
 306  	//          const char *name,
 307  	//          void *value,
 308  	//          size_t size,
 309  	//          u_int32_t position,
 310  	//          int options
 311  	//      );
 312  	//
 313  	// position specifies the offset within the extended attribute. In the
 314  	// current implementation, only the resource fork extended attribute makes
 315  	// use of this argument. For all others, position is reserved. We simply
 316  	// default to setting it to zero.
 317  	return setxattr(path, attr, xattrPointer(data), len(data), 0, flags)
 318  }
 319  
 320  func Lsetxattr(link string, attr string, data []byte, flags int) (err error) {
 321  	return setxattr(link, attr, xattrPointer(data), len(data), 0, flags|XATTR_NOFOLLOW)
 322  }
 323  
 324  //sys	fsetxattr(fd int, attr string, data *byte, size int, position uint32, options int) (err error)
 325  
 326  func Fsetxattr(fd int, attr string, data []byte, flags int) (err error) {
 327  	return fsetxattr(fd, attr, xattrPointer(data), len(data), 0, 0)
 328  }
 329  
 330  //sys	removexattr(path string, attr string, options int) (err error)
 331  
 332  func Removexattr(path string, attr string) (err error) {
 333  	// We wrap around and explicitly zero out the options provided to the OS X
 334  	// implementation of removexattr, we do so for interoperability with the
 335  	// linux variant.
 336  	return removexattr(path, attr, 0)
 337  }
 338  
 339  func Lremovexattr(link string, attr string) (err error) {
 340  	return removexattr(link, attr, XATTR_NOFOLLOW)
 341  }
 342  
 343  //sys	fremovexattr(fd int, attr string, options int) (err error)
 344  
 345  func Fremovexattr(fd int, attr string) (err error) {
 346  	return fremovexattr(fd, attr, 0)
 347  }
 348  
 349  //sys	listxattr(path string, dest *byte, size int, options int) (sz int, err error)
 350  
 351  func Listxattr(path string, dest []byte) (sz int, err error) {
 352  	return listxattr(path, xattrPointer(dest), len(dest), 0)
 353  }
 354  
 355  func Llistxattr(link string, dest []byte) (sz int, err error) {
 356  	return listxattr(link, xattrPointer(dest), len(dest), XATTR_NOFOLLOW)
 357  }
 358  
 359  //sys	flistxattr(fd int, dest *byte, size int, options int) (sz int, err error)
 360  
 361  func Flistxattr(fd int, dest []byte) (sz int, err error) {
 362  	return flistxattr(fd, xattrPointer(dest), len(dest), 0)
 363  }
 364  
 365  //sys	utimensat(dirfd int, path string, times *[2]Timespec, flags int) (err error)
 366  
 367  /*
 368   * Wrapped
 369   */
 370  
 371  //sys	fcntl(fd int, cmd int, arg int) (val int, err error)
 372  
 373  //sys	kill(pid int, signum int, posix int) (err error)
 374  
 375  func Kill(pid int, signum syscall.Signal) (err error) { return kill(pid, int(signum), 1) }
 376  
 377  //sys	ioctl(fd int, req uint, arg uintptr) (err error)
 378  //sys	ioctlPtr(fd int, req uint, arg unsafe.Pointer) (err error) = SYS_IOCTL
 379  
 380  func IoctlCtlInfo(fd int, ctlInfo *CtlInfo) error {
 381  	return ioctlPtr(fd, CTLIOCGINFO, unsafe.Pointer(ctlInfo))
 382  }
 383  
 384  // IfreqMTU is struct ifreq used to get or set a network device's MTU.
 385  type IfreqMTU struct {
 386  	Name [IFNAMSIZ]byte
 387  	MTU  int32
 388  }
 389  
 390  // IoctlGetIfreqMTU performs the SIOCGIFMTU ioctl operation on fd to get the MTU
 391  // of the network device specified by ifname.
 392  func IoctlGetIfreqMTU(fd int, ifname string) (*IfreqMTU, error) {
 393  	var ifreq IfreqMTU
 394  	copy(ifreq.Name[:], ifname)
 395  	err := ioctlPtr(fd, SIOCGIFMTU, unsafe.Pointer(&ifreq))
 396  	return &ifreq, err
 397  }
 398  
 399  // IoctlSetIfreqMTU performs the SIOCSIFMTU ioctl operation on fd to set the MTU
 400  // of the network device specified by ifreq.Name.
 401  func IoctlSetIfreqMTU(fd int, ifreq *IfreqMTU) error {
 402  	return ioctlPtr(fd, SIOCSIFMTU, unsafe.Pointer(ifreq))
 403  }
 404  
 405  //sys	renamexNp(from string, to string, flag uint32) (err error)
 406  
 407  func RenamexNp(from string, to string, flag uint32) (err error) {
 408  	return renamexNp(from, to, flag)
 409  }
 410  
 411  //sys	renameatxNp(fromfd int, from string, tofd int, to string, flag uint32) (err error)
 412  
 413  func RenameatxNp(fromfd int, from string, tofd int, to string, flag uint32) (err error) {
 414  	return renameatxNp(fromfd, from, tofd, to, flag)
 415  }
 416  
 417  //sys	sysctl(mib []_C_int, old *byte, oldlen *uintptr, new *byte, newlen uintptr) (err error) = SYS_SYSCTL
 418  
 419  func Uname(uname *Utsname) error {
 420  	mib := []_C_int{CTL_KERN, KERN_OSTYPE}
 421  	n := unsafe.Sizeof(uname.Sysname)
 422  	if err := sysctl(mib, &uname.Sysname[0], &n, nil, 0); err != nil {
 423  		return err
 424  	}
 425  
 426  	mib = []_C_int{CTL_KERN, KERN_HOSTNAME}
 427  	n = unsafe.Sizeof(uname.Nodename)
 428  	if err := sysctl(mib, &uname.Nodename[0], &n, nil, 0); err != nil {
 429  		return err
 430  	}
 431  
 432  	mib = []_C_int{CTL_KERN, KERN_OSRELEASE}
 433  	n = unsafe.Sizeof(uname.Release)
 434  	if err := sysctl(mib, &uname.Release[0], &n, nil, 0); err != nil {
 435  		return err
 436  	}
 437  
 438  	mib = []_C_int{CTL_KERN, KERN_VERSION}
 439  	n = unsafe.Sizeof(uname.Version)
 440  	if err := sysctl(mib, &uname.Version[0], &n, nil, 0); err != nil {
 441  		return err
 442  	}
 443  
 444  	// The version might have newlines or tabs in it, convert them to
 445  	// spaces.
 446  	for i, b := range uname.Version {
 447  		if b == '\n' || b == '\t' {
 448  			if i == len(uname.Version)-1 {
 449  				uname.Version[i] = 0
 450  			} else {
 451  				uname.Version[i] = ' '
 452  			}
 453  		}
 454  	}
 455  
 456  	mib = []_C_int{CTL_HW, HW_MACHINE}
 457  	n = unsafe.Sizeof(uname.Machine)
 458  	if err := sysctl(mib, &uname.Machine[0], &n, nil, 0); err != nil {
 459  		return err
 460  	}
 461  
 462  	return nil
 463  }
 464  
 465  func Sendfile(outfd int, infd int, offset *int64, count int) (written int, err error) {
 466  	if raceenabled {
 467  		raceReleaseMerge(unsafe.Pointer(&ioSync))
 468  	}
 469  	var length = int64(count)
 470  	err = sendfile(infd, outfd, *offset, &length, nil, 0)
 471  	written = int(length)
 472  	return
 473  }
 474  
 475  func GetsockoptIPMreqn(fd, level, opt int) (*IPMreqn, error) {
 476  	var value IPMreqn
 477  	vallen := _Socklen(SizeofIPMreqn)
 478  	errno := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
 479  	return &value, errno
 480  }
 481  
 482  func SetsockoptIPMreqn(fd, level, opt int, mreq *IPMreqn) (err error) {
 483  	return setsockopt(fd, level, opt, unsafe.Pointer(mreq), unsafe.Sizeof(*mreq))
 484  }
 485  
 486  // GetsockoptXucred is a getsockopt wrapper that returns an Xucred struct.
 487  // The usual level and opt are SOL_LOCAL and LOCAL_PEERCRED, respectively.
 488  func GetsockoptXucred(fd, level, opt int) (*Xucred, error) {
 489  	x := new(Xucred)
 490  	vallen := _Socklen(SizeofXucred)
 491  	err := getsockopt(fd, level, opt, unsafe.Pointer(x), &vallen)
 492  	return x, err
 493  }
 494  
 495  func GetsockoptTCPConnectionInfo(fd, level, opt int) (*TCPConnectionInfo, error) {
 496  	var value TCPConnectionInfo
 497  	vallen := _Socklen(SizeofTCPConnectionInfo)
 498  	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
 499  	return &value, err
 500  }
 501  
 502  func SysctlKinfoProc(name string, args ...int) (*KinfoProc, error) {
 503  	mib, err := sysctlmib(name, args...)
 504  	if err != nil {
 505  		return nil, err
 506  	}
 507  
 508  	var kinfo KinfoProc
 509  	n := uintptr(SizeofKinfoProc)
 510  	if err := sysctl(mib, (*byte)(unsafe.Pointer(&kinfo)), &n, nil, 0); err != nil {
 511  		return nil, err
 512  	}
 513  	if n != SizeofKinfoProc {
 514  		return nil, EIO
 515  	}
 516  	return &kinfo, nil
 517  }
 518  
 519  func SysctlKinfoProcSlice(name string, args ...int) ([]KinfoProc, error) {
 520  	mib, err := sysctlmib(name, args...)
 521  	if err != nil {
 522  		return nil, err
 523  	}
 524  
 525  	for {
 526  		// Find size.
 527  		n := uintptr(0)
 528  		if err := sysctl(mib, nil, &n, nil, 0); err != nil {
 529  			return nil, err
 530  		}
 531  		if n == 0 {
 532  			return nil, nil
 533  		}
 534  		if n%SizeofKinfoProc != 0 {
 535  			return nil, fmt.Errorf("sysctl() returned a size of %d, which is not a multiple of %d", n, SizeofKinfoProc)
 536  		}
 537  
 538  		// Read into buffer of that size.
 539  		buf := make([]KinfoProc, n/SizeofKinfoProc)
 540  		if err := sysctl(mib, (*byte)(unsafe.Pointer(&buf[0])), &n, nil, 0); err != nil {
 541  			if err == ENOMEM {
 542  				// Process table grew. Try again.
 543  				continue
 544  			}
 545  			return nil, err
 546  		}
 547  		if n%SizeofKinfoProc != 0 {
 548  			return nil, fmt.Errorf("sysctl() returned a size of %d, which is not a multiple of %d", n, SizeofKinfoProc)
 549  		}
 550  
 551  		// The actual call may return less than the original reported required
 552  		// size so ensure we deal with that.
 553  		return buf[:n/SizeofKinfoProc], nil
 554  	}
 555  }
 556  
 557  //sys	pthread_chdir_np(path string) (err error)
 558  
 559  func PthreadChdir(path string) (err error) {
 560  	return pthread_chdir_np(path)
 561  }
 562  
 563  //sys	pthread_fchdir_np(fd int) (err error)
 564  
 565  func PthreadFchdir(fd int) (err error) {
 566  	return pthread_fchdir_np(fd)
 567  }
 568  
 569  // Connectx calls connectx(2) to initiate a connection on a socket.
 570  //
 571  // srcIf, srcAddr, and dstAddr are filled into a [SaEndpoints] struct and passed as the endpoints argument.
 572  //
 573  //   - srcIf is the optional source interface index. 0 means unspecified.
 574  //   - srcAddr is the optional source address. nil means unspecified.
 575  //   - dstAddr is the destination address.
 576  //
 577  // On success, Connectx returns the number of bytes enqueued for transmission.
 578  func Connectx(fd int, srcIf uint32, srcAddr, dstAddr Sockaddr, associd SaeAssocID, flags uint32, iov []Iovec, connid *SaeConnID) (n uintptr, err error) {
 579  	endpoints := SaEndpoints{
 580  		Srcif: srcIf,
 581  	}
 582  
 583  	if srcAddr != nil {
 584  		addrp, addrlen, err := srcAddr.sockaddr()
 585  		if err != nil {
 586  			return 0, err
 587  		}
 588  		endpoints.Srcaddr = (*RawSockaddr)(addrp)
 589  		endpoints.Srcaddrlen = uint32(addrlen)
 590  	}
 591  
 592  	if dstAddr != nil {
 593  		addrp, addrlen, err := dstAddr.sockaddr()
 594  		if err != nil {
 595  			return 0, err
 596  		}
 597  		endpoints.Dstaddr = (*RawSockaddr)(addrp)
 598  		endpoints.Dstaddrlen = uint32(addrlen)
 599  	}
 600  
 601  	err = connectx(fd, &endpoints, associd, flags, iov, &n, connid)
 602  	return
 603  }
 604  
 605  const minIovec = 8
 606  
 607  func Readv(fd int, iovs [][]byte) (n int, err error) {
 608  	iovecs := make([]Iovec, 0, minIovec)
 609  	iovecs = appendBytes(iovecs, iovs)
 610  	n, err = readv(fd, iovecs)
 611  	readvRacedetect(iovecs, n, err)
 612  	return n, err
 613  }
 614  
 615  func Preadv(fd int, iovs [][]byte, offset int64) (n int, err error) {
 616  	iovecs := make([]Iovec, 0, minIovec)
 617  	iovecs = appendBytes(iovecs, iovs)
 618  	n, err = preadv(fd, iovecs, offset)
 619  	readvRacedetect(iovecs, n, err)
 620  	return n, err
 621  }
 622  
 623  func Writev(fd int, iovs [][]byte) (n int, err error) {
 624  	iovecs := make([]Iovec, 0, minIovec)
 625  	iovecs = appendBytes(iovecs, iovs)
 626  	if raceenabled {
 627  		raceReleaseMerge(unsafe.Pointer(&ioSync))
 628  	}
 629  	n, err = writev(fd, iovecs)
 630  	writevRacedetect(iovecs, n)
 631  	return n, err
 632  }
 633  
 634  func Pwritev(fd int, iovs [][]byte, offset int64) (n int, err error) {
 635  	iovecs := make([]Iovec, 0, minIovec)
 636  	iovecs = appendBytes(iovecs, iovs)
 637  	if raceenabled {
 638  		raceReleaseMerge(unsafe.Pointer(&ioSync))
 639  	}
 640  	n, err = pwritev(fd, iovecs, offset)
 641  	writevRacedetect(iovecs, n)
 642  	return n, err
 643  }
 644  
 645  func appendBytes(vecs []Iovec, bs [][]byte) []Iovec {
 646  	for _, b := range bs {
 647  		var v Iovec
 648  		v.SetLen(len(b))
 649  		if len(b) > 0 {
 650  			v.Base = &b[0]
 651  		} else {
 652  			v.Base = (*byte)(unsafe.Pointer(&_zero))
 653  		}
 654  		vecs = append(vecs, v)
 655  	}
 656  	return vecs
 657  }
 658  
 659  func writevRacedetect(iovecs []Iovec, n int) {
 660  	if !raceenabled {
 661  		return
 662  	}
 663  	for i := 0; n > 0 && i < len(iovecs); i++ {
 664  		m := int(iovecs[i].Len)
 665  		if m > n {
 666  			m = n
 667  		}
 668  		n -= m
 669  		if m > 0 {
 670  			raceReadRange(unsafe.Pointer(iovecs[i].Base), m)
 671  		}
 672  	}
 673  }
 674  
 675  func readvRacedetect(iovecs []Iovec, n int, err error) {
 676  	if !raceenabled {
 677  		return
 678  	}
 679  	for i := 0; n > 0 && i < len(iovecs); i++ {
 680  		m := int(iovecs[i].Len)
 681  		if m > n {
 682  			m = n
 683  		}
 684  		n -= m
 685  		if m > 0 {
 686  			raceWriteRange(unsafe.Pointer(iovecs[i].Base), m)
 687  		}
 688  	}
 689  	if err == nil {
 690  		raceAcquire(unsafe.Pointer(&ioSync))
 691  	}
 692  }
 693  
 694  //sys	connectx(fd int, endpoints *SaEndpoints, associd SaeAssocID, flags uint32, iov []Iovec, n *uintptr, connid *SaeConnID) (err error)
 695  //sys	sendfile(infd int, outfd int, offset int64, len *int64, hdtr unsafe.Pointer, flags int) (err error)
 696  
 697  //sys	shmat(id int, addr uintptr, flag int) (ret uintptr, err error)
 698  //sys	shmctl(id int, cmd int, buf *SysvShmDesc) (result int, err error)
 699  //sys	shmdt(addr uintptr) (err error)
 700  //sys	shmget(key int, size int, flag int) (id int, err error)
 701  
 702  /*
 703   * Exposed directly
 704   */
 705  //sys	Access(path string, mode uint32) (err error)
 706  //sys	Adjtime(delta *Timeval, olddelta *Timeval) (err error)
 707  //sys	Chdir(path string) (err error)
 708  //sys	Chflags(path string, flags int) (err error)
 709  //sys	Chmod(path string, mode uint32) (err error)
 710  //sys	Chown(path string, uid int, gid int) (err error)
 711  //sys	Chroot(path string) (err error)
 712  //sys	ClockGettime(clockid int32, time *Timespec) (err error)
 713  //sys	Close(fd int) (err error)
 714  //sys	Clonefile(src string, dst string, flags int) (err error)
 715  //sys	Clonefileat(srcDirfd int, src string, dstDirfd int, dst string, flags int) (err error)
 716  //sys	Dup(fd int) (nfd int, err error)
 717  //sys	Dup2(from int, to int) (err error)
 718  //sys	Exchangedata(path1 string, path2 string, options int) (err error)
 719  //sys	Exit(code int)
 720  //sys	Faccessat(dirfd int, path string, mode uint32, flags int) (err error)
 721  //sys	Fchdir(fd int) (err error)
 722  //sys	Fchflags(fd int, flags int) (err error)
 723  //sys	Fchmod(fd int, mode uint32) (err error)
 724  //sys	Fchmodat(dirfd int, path string, mode uint32, flags int) (err error)
 725  //sys	Fchown(fd int, uid int, gid int) (err error)
 726  //sys	Fchownat(dirfd int, path string, uid int, gid int, flags int) (err error)
 727  //sys	Fclonefileat(srcDirfd int, dstDirfd int, dst string, flags int) (err error)
 728  //sys	Flock(fd int, how int) (err error)
 729  //sys	Fpathconf(fd int, name int) (val int, err error)
 730  //sys	Fsync(fd int) (err error)
 731  //sys	Ftruncate(fd int, length int64) (err error)
 732  //sys	Getcwd(buf []byte) (n int, err error)
 733  //sys	Getdtablesize() (size int)
 734  //sysnb	Getegid() (egid int)
 735  //sysnb	Geteuid() (uid int)
 736  //sysnb	Getgid() (gid int)
 737  //sysnb	Getpgid(pid int) (pgid int, err error)
 738  //sysnb	Getpgrp() (pgrp int)
 739  //sysnb	Getpid() (pid int)
 740  //sysnb	Getppid() (ppid int)
 741  //sys	Getpriority(which int, who int) (prio int, err error)
 742  //sysnb	Getrlimit(which int, lim *Rlimit) (err error)
 743  //sysnb	Getrusage(who int, rusage *Rusage) (err error)
 744  //sysnb	Getsid(pid int) (sid int, err error)
 745  //sysnb	Gettimeofday(tp *Timeval) (err error)
 746  //sysnb	Getuid() (uid int)
 747  //sysnb	Issetugid() (tainted bool)
 748  //sys	Kqueue() (fd int, err error)
 749  //sys	Lchown(path string, uid int, gid int) (err error)
 750  //sys	Link(path string, link string) (err error)
 751  //sys	Linkat(pathfd int, path string, linkfd int, link string, flags int) (err error)
 752  //sys	Listen(s int, backlog int) (err error)
 753  //sys	Mkdir(path string, mode uint32) (err error)
 754  //sys	Mkdirat(dirfd int, path string, mode uint32) (err error)
 755  //sys	Mkfifo(path string, mode uint32) (err error)
 756  //sys	Mknod(path string, mode uint32, dev int) (err error)
 757  //sys	Mount(fsType string, dir string, flags int, data unsafe.Pointer) (err error)
 758  //sys	Open(path string, mode int, perm uint32) (fd int, err error)
 759  //sys	Openat(dirfd int, path string, mode int, perm uint32) (fd int, err error)
 760  //sys	Pathconf(path string, name int) (val int, err error)
 761  //sys	pread(fd int, p []byte, offset int64) (n int, err error)
 762  //sys	pwrite(fd int, p []byte, offset int64) (n int, err error)
 763  //sys	read(fd int, p []byte) (n int, err error)
 764  //sys	Readlink(path string, buf []byte) (n int, err error)
 765  //sys	Readlinkat(dirfd int, path string, buf []byte) (n int, err error)
 766  //sys	Rename(from string, to string) (err error)
 767  //sys	Renameat(fromfd int, from string, tofd int, to string) (err error)
 768  //sys	Revoke(path string) (err error)
 769  //sys	Rmdir(path string) (err error)
 770  //sys	Seek(fd int, offset int64, whence int) (newoffset int64, err error) = SYS_LSEEK
 771  //sys	Select(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (n int, err error)
 772  //sys	Setattrlist(path string, attrlist *Attrlist, attrBuf []byte, options int) (err error)
 773  //sys	Setegid(egid int) (err error)
 774  //sysnb	Seteuid(euid int) (err error)
 775  //sysnb	Setgid(gid int) (err error)
 776  //sys	Setlogin(name string) (err error)
 777  //sysnb	Setpgid(pid int, pgid int) (err error)
 778  //sys	Setpriority(which int, who int, prio int) (err error)
 779  //sys	Setprivexec(flag int) (err error)
 780  //sysnb	Setregid(rgid int, egid int) (err error)
 781  //sysnb	Setreuid(ruid int, euid int) (err error)
 782  //sysnb	Setsid() (pid int, err error)
 783  //sysnb	Settimeofday(tp *Timeval) (err error)
 784  //sysnb	Setuid(uid int) (err error)
 785  //sys	Symlink(path string, link string) (err error)
 786  //sys	Symlinkat(oldpath string, newdirfd int, newpath string) (err error)
 787  //sys	Sync() (err error)
 788  //sys	Truncate(path string, length int64) (err error)
 789  //sys	Umask(newmask int) (oldmask int)
 790  //sys	Undelete(path string) (err error)
 791  //sys	Unlink(path string) (err error)
 792  //sys	Unlinkat(dirfd int, path string, flags int) (err error)
 793  //sys	Unmount(path string, flags int) (err error)
 794  //sys	write(fd int, p []byte) (n int, err error)
 795  //sys	mmap(addr uintptr, length uintptr, prot int, flag int, fd int, pos int64) (ret uintptr, err error)
 796  //sys	munmap(addr uintptr, length uintptr) (err error)
 797  //sys	readv(fd int, iovecs []Iovec) (n int, err error)
 798  //sys	preadv(fd int, iovecs []Iovec, offset int64) (n int, err error)
 799  //sys	writev(fd int, iovecs []Iovec) (n int, err error)
 800  //sys	pwritev(fd int, iovecs []Iovec, offset int64) (n int, err error)
 801