Source: syscall_darwin.go in package golang.org/x/sys/unix

Darwin system calls. This file is compiled as ordinary Go code, but it is also input to mksyscall, which parses the //sys lines and generates system call stubs. Note that sometimes we use a lowercase //sys name and wrap it in our own nicer implementation, either here or in syscall_bsd.go or syscall_unix.go.


package unix

import (
	"runtime"
	"syscall"
	"unsafe"
)

SockaddrDatalink implements the Sockaddr interface for AF_LINK type sockets.

type SockaddrDatalink struct {
	Len    uint8
	Family uint8
	Index  uint16
	Type   uint8
	Nlen   uint8
	Alen   uint8
	Slen   uint8
	Data   [12]int8
	raw    RawSockaddrDatalink
}

SockaddrCtl implements the Sockaddr interface for AF_SYSTEM type sockets.

type SockaddrCtl struct {
	ID   uint32
	Unit uint32
	raw  RawSockaddrCtl
}

func (sa *SockaddrCtl) sockaddr() (unsafe.Pointer, _Socklen, error) {
	sa.raw.Sc_len = SizeofSockaddrCtl
	sa.raw.Sc_family = AF_SYSTEM
	sa.raw.Ss_sysaddr = AF_SYS_CONTROL
	sa.raw.Sc_id = sa.ID
	sa.raw.Sc_unit = sa.Unit
	return unsafe.Pointer(&sa.raw), SizeofSockaddrCtl, nil
}

func anyToSockaddrGOOS(fd int, rsa *RawSockaddrAny) (Sockaddr, error) {
	switch rsa.Addr.Family {
	case AF_SYSTEM:
		pp := (*RawSockaddrCtl)(unsafe.Pointer(rsa))
		if pp.Ss_sysaddr == AF_SYS_CONTROL {
			sa := new(SockaddrCtl)
			sa.ID = pp.Sc_id
			sa.Unit = pp.Sc_unit
			return sa, nil
		}
	}
	return nil, EAFNOSUPPORT
}

Some external packages rely on SYS___SYSCTL being defined to implement their own sysctl wrappers. Provide it here, even though direct syscalls are no longer supported on darwin.

const SYS___SYSCTL = SYS_SYSCTL

Translate "kern.hostname" to []_C_int{0,1,2,3}.

func nametomib(name string) (mib []_C_int, err error) {
	const siz = unsafe.Sizeof(mib[0])

NOTE(rsc): It seems strange to set the buffer to have size CTL_MAXNAME+2 but use only CTL_MAXNAME as the size. I don't know why the +2 is here, but the kernel uses +2 for its own implementation of this function. I am scared that if we don't include the +2 here, the kernel will silently write 2 words farther than we specify and we'll get memory corruption.

	var buf [CTL_MAXNAME + 2]_C_int
	n := uintptr(CTL_MAXNAME) * siz

	p := (*byte)(unsafe.Pointer(&buf[0]))
	bytes, err := ByteSliceFromString(name)
	if err != nil {
		return nil, err
	}

Magic sysctl: "setting" 0.3 to a string name lets you read back the array of integers form.

	if err = sysctl([]_C_int{0, 3}, p, &n, &bytes[0], uintptr(len(name))); err != nil {
		return nil, err
	}
	return buf[0 : n/siz], nil
}

func direntIno(buf []byte) (uint64, bool) {
	return readInt(buf, unsafe.Offsetof(Dirent{}.Ino), unsafe.Sizeof(Dirent{}.Ino))
}

func direntReclen(buf []byte) (uint64, bool) {
	return readInt(buf, unsafe.Offsetof(Dirent{}.Reclen), unsafe.Sizeof(Dirent{}.Reclen))
}

func direntNamlen(buf []byte) (uint64, bool) {
	return readInt(buf, unsafe.Offsetof(Dirent{}.Namlen), unsafe.Sizeof(Dirent{}.Namlen))
}

func PtraceAttach(pid int) (err error) { return ptrace(PT_ATTACH, pid, 0, 0) }
func PtraceDetach(pid int) (err error) { return ptrace(PT_DETACH, pid, 0, 0) }

type attrList struct {
	bitmapCount uint16
	_           uint16
	CommonAttr  uint32
	VolAttr     uint32
	DirAttr     uint32
	FileAttr    uint32
	Forkattr    uint32
}

sysnb pipe() (r int, w int, err error)


func Pipe(p []int) (err error) {
	if len(p) != 2 {
		return EINVAL
	}
	p[0], p[1], err = pipe()
	return
}

func Getfsstat(buf []Statfs_t, flags int) (n int, err error) {
	var _p0 unsafe.Pointer
	var bufsize uintptr
	if len(buf) > 0 {
		_p0 = unsafe.Pointer(&buf[0])
		bufsize = unsafe.Sizeof(Statfs_t{}) * uintptr(len(buf))
	}
	return getfsstat(_p0, bufsize, flags)
}

It's only when dest is set to NULL that the OS X implementations of getxattr() and listxattr() return the current sizes of the named attributes. An empty byte array is not sufficient. To maintain the same behaviour as the linux implementation, we wrap around the system calls and pass in NULL when dest is empty.

	var destp *byte
	if len(dest) > 0 {
		destp = &dest[0]
	}
	return destp
}

sys getxattr(path string, attr string, dest *byte, size int, position uint32, options int) (sz int, err error)


func Getxattr(path string, attr string, dest []byte) (sz int, err error) {
	return getxattr(path, attr, xattrPointer(dest), len(dest), 0, 0)
}

func Lgetxattr(link string, attr string, dest []byte) (sz int, err error) {
	return getxattr(link, attr, xattrPointer(dest), len(dest), 0, XATTR_NOFOLLOW)
}

sys fgetxattr(fd int, attr string, dest *byte, size int, position uint32, options int) (sz int, err error)


func Fgetxattr(fd int, attr string, dest []byte) (sz int, err error) {
	return fgetxattr(fd, attr, xattrPointer(dest), len(dest), 0, 0)
}

sys setxattr(path string, attr string, data *byte, size int, position uint32, options int) (err error)

The parameters for the OS X implementation vary slightly compared to the linux system call, specifically the position parameter: linux: int setxattr( const char *path, const char *name, const void *value, size_t size, int flags ); darwin: int setxattr( const char *path, const char *name, void *value, size_t size, u_int32_t position, int options ); position specifies the offset within the extended attribute. In the current implementation, only the resource fork extended attribute makes use of this argument. For all others, position is reserved. We simply default to setting it to zero.

	return setxattr(path, attr, xattrPointer(data), len(data), 0, flags)
}

func Lsetxattr(link string, attr string, data []byte, flags int) (err error) {
	return setxattr(link, attr, xattrPointer(data), len(data), 0, flags|XATTR_NOFOLLOW)
}

sys fsetxattr(fd int, attr string, data *byte, size int, position uint32, options int) (err error)


func Fsetxattr(fd int, attr string, data []byte, flags int) (err error) {
	return fsetxattr(fd, attr, xattrPointer(data), len(data), 0, 0)
}

sys removexattr(path string, attr string, options int) (err error)

We wrap around and explicitly zero out the options provided to the OS X implementation of removexattr, we do so for interoperability with the linux variant.

	return removexattr(path, attr, 0)
}

func Lremovexattr(link string, attr string) (err error) {
	return removexattr(link, attr, XATTR_NOFOLLOW)
}

sys fremovexattr(fd int, attr string, options int) (err error)


func Fremovexattr(fd int, attr string) (err error) {
	return fremovexattr(fd, attr, 0)
}

sys listxattr(path string, dest *byte, size int, options int) (sz int, err error)


func Listxattr(path string, dest []byte) (sz int, err error) {
	return listxattr(path, xattrPointer(dest), len(dest), 0)
}

func Llistxattr(link string, dest []byte) (sz int, err error) {
	return listxattr(link, xattrPointer(dest), len(dest), XATTR_NOFOLLOW)
}

sys flistxattr(fd int, dest *byte, size int, options int) (sz int, err error)


func Flistxattr(fd int, dest []byte) (sz int, err error) {
	return flistxattr(fd, xattrPointer(dest), len(dest), 0)
}

func setattrlistTimes(path string, times []Timespec, flags int) error {
	_p0, err := BytePtrFromString(path)
	if err != nil {
		return err
	}

	var attrList attrList
	attrList.bitmapCount = ATTR_BIT_MAP_COUNT
	attrList.CommonAttr = ATTR_CMN_MODTIME | ATTR_CMN_ACCTIME

order is mtime, atime: the opposite of Chtimes

	attributes := [2]Timespec{times[1], times[0]}
	options := 0
	if flags&AT_SYMLINK_NOFOLLOW != 0 {
		options |= FSOPT_NOFOLLOW
	}
	return setattrlist(
		_p0,
		unsafe.Pointer(&attrList),
		unsafe.Pointer(&attributes),
		unsafe.Sizeof(attributes),
		options)
}

sys setattrlist(path *byte, list unsafe.Pointer, buf unsafe.Pointer, size uintptr, options int) (err error)

Darwin doesn't support SYS_UTIMENSAT

	return ENOSYS
}

* Wrapped

sys fcntl(fd int, cmd int, arg int) (val int, err error)

sys kill(pid int, signum int, posix int) (err error)


func Kill(pid int, signum syscall.Signal) (err error) { return kill(pid, int(signum), 1) }

sys ioctl(fd int, req uint, arg uintptr) (err error)


func IoctlCtlInfo(fd int, ctlInfo *CtlInfo) error {
	err := ioctl(fd, CTLIOCGINFO, uintptr(unsafe.Pointer(ctlInfo)))
	runtime.KeepAlive(ctlInfo)
	return err
}

IfreqMTU is struct ifreq used to get or set a network device's MTU.

type IfreqMTU struct {
	Name [IFNAMSIZ]byte
	MTU  int32
}

IoctlGetIfreqMTU performs the SIOCGIFMTU ioctl operation on fd to get the MTU of the network device specified by ifname.

func IoctlGetIfreqMTU(fd int, ifname string) (*IfreqMTU, error) {
	var ifreq IfreqMTU
	copy(ifreq.Name[:], ifname)
	err := ioctl(fd, SIOCGIFMTU, uintptr(unsafe.Pointer(&ifreq)))
	return &ifreq, err
}

IoctlSetIfreqMTU performs the SIOCSIFMTU ioctl operation on fd to set the MTU of the network device specified by ifreq.Name.

func IoctlSetIfreqMTU(fd int, ifreq *IfreqMTU) error {
	err := ioctl(fd, SIOCSIFMTU, uintptr(unsafe.Pointer(ifreq)))
	runtime.KeepAlive(ifreq)
	return err
}

sys sysctl(mib []_C_int, old *byte, oldlen *uintptr, new *byte, newlen uintptr) (err error) = SYS_SYSCTL


func Uname(uname *Utsname) error {
	mib := []_C_int{CTL_KERN, KERN_OSTYPE}
	n := unsafe.Sizeof(uname.Sysname)
	if err := sysctl(mib, &uname.Sysname[0], &n, nil, 0); err != nil {
		return err
	}

	mib = []_C_int{CTL_KERN, KERN_HOSTNAME}
	n = unsafe.Sizeof(uname.Nodename)
	if err := sysctl(mib, &uname.Nodename[0], &n, nil, 0); err != nil {
		return err
	}

	mib = []_C_int{CTL_KERN, KERN_OSRELEASE}
	n = unsafe.Sizeof(uname.Release)
	if err := sysctl(mib, &uname.Release[0], &n, nil, 0); err != nil {
		return err
	}

	mib = []_C_int{CTL_KERN, KERN_VERSION}
	n = unsafe.Sizeof(uname.Version)
	if err := sysctl(mib, &uname.Version[0], &n, nil, 0); err != nil {
		return err
	}

The version might have newlines or tabs in it, convert them to spaces.

	for i, b := range uname.Version {
		if b == '\n' || b == '\t' {
			if i == len(uname.Version)-1 {
				uname.Version[i] = 0
			} else {
				uname.Version[i] = ' '
			}
		}
	}

	mib = []_C_int{CTL_HW, HW_MACHINE}
	n = unsafe.Sizeof(uname.Machine)
	if err := sysctl(mib, &uname.Machine[0], &n, nil, 0); err != nil {
		return err
	}

	return nil
}

func Sendfile(outfd int, infd int, offset *int64, count int) (written int, err error) {
	if raceenabled {
		raceReleaseMerge(unsafe.Pointer(&ioSync))
	}
	var length = int64(count)
	err = sendfile(infd, outfd, *offset, &length, nil, 0)
	written = int(length)
	return
}

sys sendfile(infd int, outfd int, offset int64, len *int64, hdtr unsafe.Pointer, flags int) (err error)

* Exposed directly sys Access(path string, mode uint32) (err error)sys Adjtime(delta *Timeval, olddelta *Timeval) (err error)sys Chdir(path string) (err error)sys Chflags(path string, flags int) (err error)sys Chmod(path string, mode uint32) (err error)sys Chown(path string, uid int, gid int) (err error)sys Chroot(path string) (err error)sys ClockGettime(clockid int32, time *Timespec) (err error)sys Close(fd int) (err error)sys Clonefile(src string, dst string, flags int) (err error)sys Clonefileat(srcDirfd int, src string, dstDirfd int, dst string, flags int) (err error)sys Dup(fd int) (nfd int, err error)sys Dup2(from int, to int) (err error)sys Exchangedata(path1 string, path2 string, options int) (err error)sys Exit(code int)sys Faccessat(dirfd int, path string, mode uint32, flags int) (err error)sys Fchdir(fd int) (err error)sys Fchflags(fd int, flags int) (err error)sys Fchmod(fd int, mode uint32) (err error)sys Fchmodat(dirfd int, path string, mode uint32, flags int) (err error)sys Fchown(fd int, uid int, gid int) (err error)sys Fchownat(dirfd int, path string, uid int, gid int, flags int) (err error)sys Fclonefileat(srcDirfd int, dstDirfd int, dst string, flags int) (err error)sys Flock(fd int, how int) (err error)sys Fpathconf(fd int, name int) (val int, err error)sys Fsync(fd int) (err error)sys Ftruncate(fd int, length int64) (err error)sys Getcwd(buf []byte) (n int, err error)sys Getdtablesize() (size int)sysnb Getegid() (egid int)sysnb Geteuid() (uid int)sysnb Getgid() (gid int)sysnb Getpgid(pid int) (pgid int, err error)sysnb Getpgrp() (pgrp int)sysnb Getpid() (pid int)sysnb Getppid() (ppid int)sys Getpriority(which int, who int) (prio int, err error)sysnb Getrlimit(which int, lim *Rlimit) (err error)sysnb Getrusage(who int, rusage *Rusage) (err error)sysnb Getsid(pid int) (sid int, err error)sysnb Gettimeofday(tp *Timeval) (err error)sysnb Getuid() (uid int)sysnb Issetugid() (tainted bool)sys Kqueue() (fd int, err error)sys Lchown(path string, uid int, gid int) (err error)sys Link(path string, link string) (err error)sys Linkat(pathfd int, path string, linkfd int, link string, flags int) (err error)sys Listen(s int, backlog int) (err error)sys Mkdir(path string, mode uint32) (err error)sys Mkdirat(dirfd int, path string, mode uint32) (err error)sys Mkfifo(path string, mode uint32) (err error)sys Mknod(path string, mode uint32, dev int) (err error)sys Open(path string, mode int, perm uint32) (fd int, err error)sys Openat(dirfd int, path string, mode int, perm uint32) (fd int, err error)sys Pathconf(path string, name int) (val int, err error)sys Pread(fd int, p []byte, offset int64) (n int, err error)sys Pwrite(fd int, p []byte, offset int64) (n int, err error)sys read(fd int, p []byte) (n int, err error)sys Readlink(path string, buf []byte) (n int, err error)sys Readlinkat(dirfd int, path string, buf []byte) (n int, err error)sys Rename(from string, to string) (err error)sys Renameat(fromfd int, from string, tofd int, to string) (err error)sys Revoke(path string) (err error)sys Rmdir(path string) (err error)sys Seek(fd int, offset int64, whence int) (newoffset int64, err error) = SYS_LSEEKsys Select(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (n int, err error)sys Setegid(egid int) (err error)sysnb Seteuid(euid int) (err error)sysnb Setgid(gid int) (err error)sys Setlogin(name string) (err error)sysnb Setpgid(pid int, pgid int) (err error)sys Setpriority(which int, who int, prio int) (err error)sys Setprivexec(flag int) (err error)sysnb Setregid(rgid int, egid int) (err error)sysnb Setreuid(ruid int, euid int) (err error)sysnb Setrlimit(which int, lim *Rlimit) (err error)sysnb Setsid() (pid int, err error)sysnb Settimeofday(tp *Timeval) (err error)sysnb Setuid(uid int) (err error)sys Symlink(path string, link string) (err error)sys Symlinkat(oldpath string, newdirfd int, newpath string) (err error)sys Sync() (err error)sys Truncate(path string, length int64) (err error)sys Umask(newmask int) (oldmask int)sys Undelete(path string) (err error)sys Unlink(path string) (err error)sys Unlinkat(dirfd int, path string, flags int) (err error)sys Unmount(path string, flags int) (err error)sys write(fd int, p []byte) (n int, err error)sys mmap(addr uintptr, length uintptr, prot int, flag int, fd int, pos int64) (ret uintptr, err error)sys munmap(addr uintptr, length uintptr) (err error)sys readlen(fd int, buf *byte, nbuf int) (n int, err error) = SYS_READsys writelen(fd int, buf *byte, nbuf int) (n int, err error) = SYS_WRITE

* Unimplemented Profil Sigaction Sigprocmask Getlogin Sigpending Sigaltstack Ioctl Reboot Execve Vfork Sbrk Sstk Ovadvise Mincore Setitimer Swapon Select Sigsuspend Readv Writev Nfssvc Getfh Quotactl Mount Csops Waitid Add_profil Kdebug_trace Sigreturn Atsocket Kqueue_from_portset_np Kqueue_portset Getattrlist Setattrlist Getdirentriesattr Searchfs Delete Copyfile Watchevent Waitevent Modwatch Fsctl Initgroups Posix_spawn Nfsclnt Fhopen Minherit Semsys Msgsys Shmsys Semctl Semget Semop Msgctl Msgget Msgsnd Msgrcv Shmat Shmctl Shmdt Shmget Shm_open Shm_unlink Sem_open Sem_close Sem_unlink Sem_wait Sem_trywait Sem_post Sem_getvalue Sem_init Sem_destroy Open_extended Umask_extended Stat_extended Lstat_extended Fstat_extended Chmod_extended Fchmod_extended Access_extended Settid Gettid Setsgroups Getsgroups Setwgroups Getwgroups Mkfifo_extended Mkdir_extended Identitysvc Shared_region_check_np Shared_region_map_np __pthread_mutex_destroy __pthread_mutex_init __pthread_mutex_lock __pthread_mutex_trylock __pthread_mutex_unlock __pthread_cond_init __pthread_cond_destroy __pthread_cond_broadcast __pthread_cond_signal Setsid_with_pid __pthread_cond_timedwait Aio_fsync Aio_return Aio_suspend Aio_cancel Aio_error Aio_read Aio_write Lio_listio __pthread_cond_wait Iopolicysys __pthread_kill __pthread_sigmask __sigwait __disable_threadsignal __pthread_markcancel __pthread_canceled __semwait_signal Proc_info sendfile Stat64_extended Lstat64_extended Fstat64_extended __pthread_chdir __pthread_fchdir Audit Auditon Getauid Setauid Getaudit Setaudit Getaudit_addr Setaudit_addr Auditctl Bsdthread_create Bsdthread_terminate Stack_snapshot Bsdthread_register Workq_open Workq_ops __mac_execve __mac_syscall __mac_get_file __mac_set_file __mac_get_link __mac_set_link __mac_get_proc __mac_set_proc __mac_get_fd __mac_set_fd __mac_get_pid __mac_get_lcid __mac_get_lctx __mac_set_lctx Setlcid Read_nocancel Write_nocancel Open_nocancel Close_nocancel Wait4_nocancel Recvmsg_nocancel Sendmsg_nocancel Recvfrom_nocancel Accept_nocancel Fcntl_nocancel Select_nocancel Fsync_nocancel Connect_nocancel Sigsuspend_nocancel Readv_nocancel Writev_nocancel Sendto_nocancel Pread_nocancel Pwrite_nocancel Waitid_nocancel Poll_nocancel Msgsnd_nocancel Msgrcv_nocancel Sem_wait_nocancel Aio_suspend_nocancel __sigwait_nocancel __semwait_signal_nocancel __mac_mount __mac_get_mount