cubefs

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// Copyright 2009 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris
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// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris
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package unix
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import (
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	"bytes"
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	"sort"
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	"sync"
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	"syscall"
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	"unsafe"
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)
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var (
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	Stdin  = 0
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	Stdout = 1
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	Stderr = 2
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)
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// Do the interface allocations only once for common
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// Errno values.
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var (
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	errEAGAIN error = syscall.EAGAIN
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	errEINVAL error = syscall.EINVAL
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	errENOENT error = syscall.ENOENT
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)
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var (
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	signalNameMapOnce sync.Once
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	signalNameMap     map[string]syscall.Signal
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)
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// errnoErr returns common boxed Errno values, to prevent
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// allocations at runtime.
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func errnoErr(e syscall.Errno) error {
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	switch e {
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	case 0:
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		return nil
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	case EAGAIN:
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		return errEAGAIN
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	case EINVAL:
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		return errEINVAL
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	case ENOENT:
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		return errENOENT
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	}
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	return e
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}
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// ErrnoName returns the error name for error number e.
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func ErrnoName(e syscall.Errno) string {
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	i := sort.Search(len(errorList), func(i int) bool {
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		return errorList[i].num >= e
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	})
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	if i < len(errorList) && errorList[i].num == e {
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		return errorList[i].name
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	}
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	return ""
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}
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// SignalName returns the signal name for signal number s.
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func SignalName(s syscall.Signal) string {
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	i := sort.Search(len(signalList), func(i int) bool {
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		return signalList[i].num >= s
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	})
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	if i < len(signalList) && signalList[i].num == s {
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		return signalList[i].name
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	}
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	return ""
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}
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// SignalNum returns the syscall.Signal for signal named s,
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// or 0 if a signal with such name is not found.
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// The signal name should start with "SIG".
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func SignalNum(s string) syscall.Signal {
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	signalNameMapOnce.Do(func() {
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		signalNameMap = make(map[string]syscall.Signal, len(signalList))
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		for _, signal := range signalList {
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			signalNameMap[signal.name] = signal.num
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		}
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	})
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	return signalNameMap[s]
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}
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// clen returns the index of the first NULL byte in n or len(n) if n contains no NULL byte.
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func clen(n []byte) int {
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	i := bytes.IndexByte(n, 0)
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	if i == -1 {
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		i = len(n)
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	}
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	return i
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}
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// Mmap manager, for use by operating system-specific implementations.
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type mmapper struct {
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	sync.Mutex
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	active map[*byte][]byte // active mappings; key is last byte in mapping
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	mmap   func(addr, length uintptr, prot, flags, fd int, offset int64) (uintptr, error)
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	munmap func(addr uintptr, length uintptr) error
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}
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func (m *mmapper) Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) {
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	if length <= 0 {
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		return nil, EINVAL
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	}
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	// Map the requested memory.
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	addr, errno := m.mmap(0, uintptr(length), prot, flags, fd, offset)
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	if errno != nil {
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		return nil, errno
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	}
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	// Use unsafe to convert addr into a []byte.
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	b := unsafe.Slice((*byte)(unsafe.Pointer(addr)), length)
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	// Register mapping in m and return it.
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	p := &b[cap(b)-1]
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	m.Lock()
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	defer m.Unlock()
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	m.active[p] = b
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	return b, nil
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}
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func (m *mmapper) Munmap(data []byte) (err error) {
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	if len(data) == 0 || len(data) != cap(data) {
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		return EINVAL
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	}
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	// Find the base of the mapping.
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	p := &data[cap(data)-1]
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	m.Lock()
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	defer m.Unlock()
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	b := m.active[p]
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	if b == nil || &b[0] != &data[0] {
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		return EINVAL
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	}
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	// Unmap the memory and update m.
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	if errno := m.munmap(uintptr(unsafe.Pointer(&b[0])), uintptr(len(b))); errno != nil {
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		return errno
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	}
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	delete(m.active, p)
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	return nil
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}
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func Read(fd int, p []byte) (n int, err error) {
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	n, err = read(fd, p)
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	if raceenabled {
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		if n > 0 {
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			raceWriteRange(unsafe.Pointer(&p[0]), n)
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		}
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		if err == nil {
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			raceAcquire(unsafe.Pointer(&ioSync))
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		}
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	}
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	return
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}
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func Write(fd int, p []byte) (n int, err error) {
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	if raceenabled {
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		raceReleaseMerge(unsafe.Pointer(&ioSync))
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	}
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	n, err = write(fd, p)
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	if raceenabled && n > 0 {
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		raceReadRange(unsafe.Pointer(&p[0]), n)
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	}
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	return
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}
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func Pread(fd int, p []byte, offset int64) (n int, err error) {
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	n, err = pread(fd, p, offset)
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	if raceenabled {
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		if n > 0 {
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			raceWriteRange(unsafe.Pointer(&p[0]), n)
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		}
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		if err == nil {
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			raceAcquire(unsafe.Pointer(&ioSync))
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		}
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	}
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	return
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}
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func Pwrite(fd int, p []byte, offset int64) (n int, err error) {
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	if raceenabled {
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		raceReleaseMerge(unsafe.Pointer(&ioSync))
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	}
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	n, err = pwrite(fd, p, offset)
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	if raceenabled && n > 0 {
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		raceReadRange(unsafe.Pointer(&p[0]), n)
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	}
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	return
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}
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// For testing: clients can set this flag to force
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// creation of IPv6 sockets to return EAFNOSUPPORT.
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var SocketDisableIPv6 bool
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// Sockaddr represents a socket address.
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type Sockaddr interface {
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	sockaddr() (ptr unsafe.Pointer, len _Socklen, err error) // lowercase; only we can define Sockaddrs
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}
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// SockaddrInet4 implements the Sockaddr interface for AF_INET type sockets.
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type SockaddrInet4 struct {
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	Port int
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	Addr [4]byte
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	raw  RawSockaddrInet4
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}
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// SockaddrInet6 implements the Sockaddr interface for AF_INET6 type sockets.
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type SockaddrInet6 struct {
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	Port   int
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	ZoneId uint32
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	Addr   [16]byte
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	raw    RawSockaddrInet6
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}
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// SockaddrUnix implements the Sockaddr interface for AF_UNIX type sockets.
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type SockaddrUnix struct {
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	Name string
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	raw  RawSockaddrUnix
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}
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func Bind(fd int, sa Sockaddr) (err error) {
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	ptr, n, err := sa.sockaddr()
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	if err != nil {
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		return err
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	}
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	return bind(fd, ptr, n)
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}
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func Connect(fd int, sa Sockaddr) (err error) {
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	ptr, n, err := sa.sockaddr()
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	if err != nil {
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		return err
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	}
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	return connect(fd, ptr, n)
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}
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func Getpeername(fd int) (sa Sockaddr, err error) {
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	var rsa RawSockaddrAny
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	var len _Socklen = SizeofSockaddrAny
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	if err = getpeername(fd, &rsa, &len); err != nil {
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		return
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	}
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	return anyToSockaddr(fd, &rsa)
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}
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func GetsockoptByte(fd, level, opt int) (value byte, err error) {
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	var n byte
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	vallen := _Socklen(1)
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	err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen)
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	return n, err
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}
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func GetsockoptInt(fd, level, opt int) (value int, err error) {
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	var n int32
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	vallen := _Socklen(4)
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	err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen)
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	return int(n), err
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}
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func GetsockoptInet4Addr(fd, level, opt int) (value [4]byte, err error) {
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	vallen := _Socklen(4)
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	err = getsockopt(fd, level, opt, unsafe.Pointer(&value[0]), &vallen)
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	return value, err
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}
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func GetsockoptIPMreq(fd, level, opt int) (*IPMreq, error) {
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	var value IPMreq
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	vallen := _Socklen(SizeofIPMreq)
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	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
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	return &value, err
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}
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func GetsockoptIPv6Mreq(fd, level, opt int) (*IPv6Mreq, error) {
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	var value IPv6Mreq
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	vallen := _Socklen(SizeofIPv6Mreq)
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	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
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	return &value, err
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}
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func GetsockoptIPv6MTUInfo(fd, level, opt int) (*IPv6MTUInfo, error) {
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	var value IPv6MTUInfo
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	vallen := _Socklen(SizeofIPv6MTUInfo)
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	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
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	return &value, err
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}
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func GetsockoptICMPv6Filter(fd, level, opt int) (*ICMPv6Filter, error) {
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	var value ICMPv6Filter
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	vallen := _Socklen(SizeofICMPv6Filter)
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	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
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	return &value, err
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}
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func GetsockoptLinger(fd, level, opt int) (*Linger, error) {
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	var linger Linger
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	vallen := _Socklen(SizeofLinger)
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	err := getsockopt(fd, level, opt, unsafe.Pointer(&linger), &vallen)
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	return &linger, err
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}
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func GetsockoptTimeval(fd, level, opt int) (*Timeval, error) {
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	var tv Timeval
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	vallen := _Socklen(unsafe.Sizeof(tv))
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	err := getsockopt(fd, level, opt, unsafe.Pointer(&tv), &vallen)
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	return &tv, err
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}
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func GetsockoptUint64(fd, level, opt int) (value uint64, err error) {
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	var n uint64
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	vallen := _Socklen(8)
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	err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen)
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	return n, err
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}
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func Recvfrom(fd int, p []byte, flags int) (n int, from Sockaddr, err error) {
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	var rsa RawSockaddrAny
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	var len _Socklen = SizeofSockaddrAny
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	if n, err = recvfrom(fd, p, flags, &rsa, &len); err != nil {
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		return
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	}
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	if rsa.Addr.Family != AF_UNSPEC {
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		from, err = anyToSockaddr(fd, &rsa)
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	}
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	return
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}
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// Recvmsg receives a message from a socket using the recvmsg system call. The
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// received non-control data will be written to p, and any "out of band"
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// control data will be written to oob. The flags are passed to recvmsg.
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//
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// The results are:
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//   - n is the number of non-control data bytes read into p
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//   - oobn is the number of control data bytes read into oob; this may be interpreted using [ParseSocketControlMessage]
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//   - recvflags is flags returned by recvmsg
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//   - from is the address of the sender
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//
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// If the underlying socket type is not SOCK_DGRAM, a received message
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// containing oob data and a single '\0' of non-control data is treated as if
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// the message contained only control data, i.e. n will be zero on return.
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func Recvmsg(fd int, p, oob []byte, flags int) (n, oobn int, recvflags int, from Sockaddr, err error) {
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	var iov [1]Iovec
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	if len(p) > 0 {
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		iov[0].Base = &p[0]
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		iov[0].SetLen(len(p))
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	}
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	var rsa RawSockaddrAny
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	n, oobn, recvflags, err = recvmsgRaw(fd, iov[:], oob, flags, &rsa)
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	// source address is only specified if the socket is unconnected
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	if rsa.Addr.Family != AF_UNSPEC {
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		from, err = anyToSockaddr(fd, &rsa)
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	}
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	return
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}
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362
// RecvmsgBuffers receives a message from a socket using the recvmsg system
363
// call. This function is equivalent to Recvmsg, but non-control data read is
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// scattered into the buffers slices.
365
func RecvmsgBuffers(fd int, buffers [][]byte, oob []byte, flags int) (n, oobn int, recvflags int, from Sockaddr, err error) {
366
	iov := make([]Iovec, len(buffers))
367
	for i := range buffers {
368
		if len(buffers[i]) > 0 {
369
			iov[i].Base = &buffers[i][0]
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			iov[i].SetLen(len(buffers[i]))
371
		} else {
372
			iov[i].Base = (*byte)(unsafe.Pointer(&_zero))
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		}
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	}
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	var rsa RawSockaddrAny
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	n, oobn, recvflags, err = recvmsgRaw(fd, iov, oob, flags, &rsa)
377
	if err == nil && rsa.Addr.Family != AF_UNSPEC {
378
		from, err = anyToSockaddr(fd, &rsa)
379
	}
380
	return
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}
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383
// Sendmsg sends a message on a socket to an address using the sendmsg system
384
// call. This function is equivalent to SendmsgN, but does not return the
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// number of bytes actually sent.
386
func Sendmsg(fd int, p, oob []byte, to Sockaddr, flags int) (err error) {
387
	_, err = SendmsgN(fd, p, oob, to, flags)
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	return
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}
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391
// SendmsgN sends a message on a socket to an address using the sendmsg system
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// call. p contains the non-control data to send, and oob contains the "out of
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// band" control data. The flags are passed to sendmsg. The number of
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// non-control bytes actually written to the socket is returned.
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//
396
// Some socket types do not support sending control data without accompanying
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// non-control data. If p is empty, and oob contains control data, and the
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// underlying socket type is not SOCK_DGRAM, p will be treated as containing a
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// single '\0' and the return value will indicate zero bytes sent.
400
//
401
// The Go function Recvmsg, if called with an empty p and a non-empty oob,
402
// will read and ignore this additional '\0'.  If the message is received by
403
// code that does not use Recvmsg, or that does not use Go at all, that code
404
// will need to be written to expect and ignore the additional '\0'.
405
//
406
// If you need to send non-empty oob with p actually empty, and if the
407
// underlying socket type supports it, you can do so via a raw system call as
408
// follows:
409
//
410
//	msg := &unix.Msghdr{
411
//	    Control: &oob[0],
412
//	}
413
//	msg.SetControllen(len(oob))
414
//	n, _, errno := unix.Syscall(unix.SYS_SENDMSG, uintptr(fd), uintptr(unsafe.Pointer(msg)), flags)
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func SendmsgN(fd int, p, oob []byte, to Sockaddr, flags int) (n int, err error) {
416
	var iov [1]Iovec
417
	if len(p) > 0 {
418
		iov[0].Base = &p[0]
419
		iov[0].SetLen(len(p))
420
	}
421
	var ptr unsafe.Pointer
422
	var salen _Socklen
423
	if to != nil {
424
		ptr, salen, err = to.sockaddr()
425
		if err != nil {
426
			return 0, err
427
		}
428
	}
429
	return sendmsgN(fd, iov[:], oob, ptr, salen, flags)
430
}
431

432
// SendmsgBuffers sends a message on a socket to an address using the sendmsg
433
// system call. This function is equivalent to SendmsgN, but the non-control
434
// data is gathered from buffers.
435
func SendmsgBuffers(fd int, buffers [][]byte, oob []byte, to Sockaddr, flags int) (n int, err error) {
436
	iov := make([]Iovec, len(buffers))
437
	for i := range buffers {
438
		if len(buffers[i]) > 0 {
439
			iov[i].Base = &buffers[i][0]
440
			iov[i].SetLen(len(buffers[i]))
441
		} else {
442
			iov[i].Base = (*byte)(unsafe.Pointer(&_zero))
443
		}
444
	}
445
	var ptr unsafe.Pointer
446
	var salen _Socklen
447
	if to != nil {
448
		ptr, salen, err = to.sockaddr()
449
		if err != nil {
450
			return 0, err
451
		}
452
	}
453
	return sendmsgN(fd, iov, oob, ptr, salen, flags)
454
}
455

456
func Send(s int, buf []byte, flags int) (err error) {
457
	return sendto(s, buf, flags, nil, 0)
458
}
459

460
func Sendto(fd int, p []byte, flags int, to Sockaddr) (err error) {
461
	var ptr unsafe.Pointer
462
	var salen _Socklen
463
	if to != nil {
464
		ptr, salen, err = to.sockaddr()
465
		if err != nil {
466
			return err
467
		}
468
	}
469
	return sendto(fd, p, flags, ptr, salen)
470
}
471

472
func SetsockoptByte(fd, level, opt int, value byte) (err error) {
473
	return setsockopt(fd, level, opt, unsafe.Pointer(&value), 1)
474
}
475

476
func SetsockoptInt(fd, level, opt int, value int) (err error) {
477
	var n = int32(value)
478
	return setsockopt(fd, level, opt, unsafe.Pointer(&n), 4)
479
}
480

481
func SetsockoptInet4Addr(fd, level, opt int, value [4]byte) (err error) {
482
	return setsockopt(fd, level, opt, unsafe.Pointer(&value[0]), 4)
483
}
484

485
func SetsockoptIPMreq(fd, level, opt int, mreq *IPMreq) (err error) {
486
	return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPMreq)
487
}
488

489
func SetsockoptIPv6Mreq(fd, level, opt int, mreq *IPv6Mreq) (err error) {
490
	return setsockopt(fd, level, opt, unsafe.Pointer(mreq), SizeofIPv6Mreq)
491
}
492

493
func SetsockoptICMPv6Filter(fd, level, opt int, filter *ICMPv6Filter) error {
494
	return setsockopt(fd, level, opt, unsafe.Pointer(filter), SizeofICMPv6Filter)
495
}
496

497
func SetsockoptLinger(fd, level, opt int, l *Linger) (err error) {
498
	return setsockopt(fd, level, opt, unsafe.Pointer(l), SizeofLinger)
499
}
500

501
func SetsockoptString(fd, level, opt int, s string) (err error) {
502
	var p unsafe.Pointer
503
	if len(s) > 0 {
504
		p = unsafe.Pointer(&[]byte(s)[0])
505
	}
506
	return setsockopt(fd, level, opt, p, uintptr(len(s)))
507
}
508

509
func SetsockoptTimeval(fd, level, opt int, tv *Timeval) (err error) {
510
	return setsockopt(fd, level, opt, unsafe.Pointer(tv), unsafe.Sizeof(*tv))
511
}
512

513
func SetsockoptUint64(fd, level, opt int, value uint64) (err error) {
514
	return setsockopt(fd, level, opt, unsafe.Pointer(&value), 8)
515
}
516

517
func Socket(domain, typ, proto int) (fd int, err error) {
518
	if domain == AF_INET6 && SocketDisableIPv6 {
519
		return -1, EAFNOSUPPORT
520
	}
521
	fd, err = socket(domain, typ, proto)
522
	return
523
}
524

525
func Socketpair(domain, typ, proto int) (fd [2]int, err error) {
526
	var fdx [2]int32
527
	err = socketpair(domain, typ, proto, &fdx)
528
	if err == nil {
529
		fd[0] = int(fdx[0])
530
		fd[1] = int(fdx[1])
531
	}
532
	return
533
}
534

535
var ioSync int64
536

537
func CloseOnExec(fd int) { fcntl(fd, F_SETFD, FD_CLOEXEC) }
538

539
func SetNonblock(fd int, nonblocking bool) (err error) {
540
	flag, err := fcntl(fd, F_GETFL, 0)
541
	if err != nil {
542
		return err
543
	}
544
	if nonblocking {
545
		flag |= O_NONBLOCK
546
	} else {
547
		flag &= ^O_NONBLOCK
548
	}
549
	_, err = fcntl(fd, F_SETFL, flag)
550
	return err
551
}
552

553
// Exec calls execve(2), which replaces the calling executable in the process
554
// tree. argv0 should be the full path to an executable ("/bin/ls") and the
555
// executable name should also be the first argument in argv (["ls", "-l"]).
556
// envv are the environment variables that should be passed to the new
557
// process (["USER=go", "PWD=/tmp"]).
558
func Exec(argv0 string, argv []string, envv []string) error {
559
	return syscall.Exec(argv0, argv, envv)
560
}
561

562
// Lutimes sets the access and modification times tv on path. If path refers to
563
// a symlink, it is not dereferenced and the timestamps are set on the symlink.
564
// If tv is nil, the access and modification times are set to the current time.
565
// Otherwise tv must contain exactly 2 elements, with access time as the first
566
// element and modification time as the second element.
567
func Lutimes(path string, tv []Timeval) error {
568
	if tv == nil {
569
		return UtimesNanoAt(AT_FDCWD, path, nil, AT_SYMLINK_NOFOLLOW)
570
	}
571
	if len(tv) != 2 {
572
		return EINVAL
573
	}
574
	ts := []Timespec{
575
		NsecToTimespec(TimevalToNsec(tv[0])),
576
		NsecToTimespec(TimevalToNsec(tv[1])),
577
	}
578
	return UtimesNanoAt(AT_FDCWD, path, ts, AT_SYMLINK_NOFOLLOW)
579
}
580

581
// emptyIovecs reports whether there are no bytes in the slice of Iovec.
582
func emptyIovecs(iov []Iovec) bool {
583
	for i := range iov {
584
		if iov[i].Len > 0 {
585
			return false
586
		}
587
	}
588
	return true
589
}
590

591
// Setrlimit sets a resource limit.
592
func Setrlimit(resource int, rlim *Rlimit) error {
593
	// Just call the syscall version, because as of Go 1.21
594
	// it will affect starting a new process.
595
	return syscall.Setrlimit(resource, (*syscall.Rlimit)(rlim))
596
}
597