// Copyright 2009,2010 The Go Authors. All rights reserved.

// Use of this source code is governed by a BSD-style

// license that can be found in the LICENSE file.

// FreeBSD 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 (

	"sync"

	"unsafe"

)

const (

	SYS_FSTAT_FREEBSD12         = 551 // { int fstat(int fd, _Out_ struct stat *sb); }

	SYS_FSTATAT_FREEBSD12       = 552 // { int fstatat(int fd, _In_z_ char *path, \

	SYS_GETDIRENTRIES_FREEBSD12 = 554 // { ssize_t getdirentries(int fd, \

	SYS_STATFS_FREEBSD12        = 555 // { int statfs(_In_z_ char *path, \

	SYS_FSTATFS_FREEBSD12       = 556 // { int fstatfs(int fd, \

	SYS_GETFSSTAT_FREEBSD12     = 557 // { int getfsstat( \

	SYS_MKNODAT_FREEBSD12       = 559 // { int mknodat(int fd, _In_z_ char *path, \

)

// See https://www.freebsd.org/doc/en_US.ISO8859-1/books/porters-handbook/versions.html.

var (

	osreldateOnce sync.Once

	osreldate     uint32

)

// INO64_FIRST from /usr/src/lib/libc/sys/compat-ino64.h

const _ino64First = 1200031

func supportsABI(ver uint32) bool {

	osreldateOnce.Do(func() { osreldate, _ = SysctlUint32("kern.osreldate") })

	return osreldate >= ver

}

// 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   [46]int8

	raw    RawSockaddrDatalink

}

// 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{}.Fileno), unsafe.Sizeof(Dirent{}.Fileno))

}

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 Pipe(p []int) (err error) {

	return Pipe2(p, 0)

}

//sysnb	pipe2(p *[2]_C_int, flags int) (err error)

func Pipe2(p []int, flags int) error {

	if len(p) != 2 {

		return EINVAL

	}

	var pp [2]_C_int

	err := pipe2(&pp, flags)

	p[0] = int(pp[0])

	p[1] = int(pp[1])

	return err

}

func GetsockoptIPMreqn(fd, level, opt int) (*IPMreqn, error) {

	var value IPMreqn

	vallen := _Socklen(SizeofIPMreqn)

	errno := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)

	return &value, errno

}

func SetsockoptIPMreqn(fd, level, opt int, mreq *IPMreqn) (err error) {

	return setsockopt(fd, level, opt, unsafe.Pointer(mreq), unsafe.Sizeof(*mreq))

}

func Accept4(fd, flags int) (nfd int, sa Sockaddr, err error) {

	var rsa RawSockaddrAny

	var len _Socklen = SizeofSockaddrAny

	nfd, err = accept4(fd, &rsa, &len, flags)

	if err != nil {

		return

	}

	if len > SizeofSockaddrAny {

		panic("RawSockaddrAny too small")

	}

	sa, err = anyToSockaddr(fd, &rsa)

	if err != nil {

		Close(nfd)

		nfd = 0

	}

	return

}

//sys	Getcwd(buf []byte) (n int, err error) = SYS___GETCWD

func Getfsstat(buf []Statfs_t, flags int) (n int, err error) {

	var (

		_p0          unsafe.Pointer

		bufsize      uintptr

		oldBuf       []statfs_freebsd11_t

		needsConvert bool

	)

	if len(buf) > 0 {

		if supportsABI(_ino64First) {

			_p0 = unsafe.Pointer(&buf[0])

			bufsize = unsafe.Sizeof(Statfs_t{}) * uintptr(len(buf))

		} else {

			n := len(buf)

			oldBuf = make([]statfs_freebsd11_t, n)

			_p0 = unsafe.Pointer(&oldBuf[0])

			bufsize = unsafe.Sizeof(statfs_freebsd11_t{}) * uintptr(n)

			needsConvert = true

		}

	}

	var sysno uintptr = SYS_GETFSSTAT

	if supportsABI(_ino64First) {

		sysno = SYS_GETFSSTAT_FREEBSD12

	}

	r0, _, e1 := Syscall(sysno, uintptr(_p0), bufsize, uintptr(flags))

	n = int(r0)

	if e1 != 0 {

		err = e1

	}

	if e1 == 0 && needsConvert {

		for i := range oldBuf {

			buf[i].convertFrom(&oldBuf[i])

		}

	}

	return

}

func setattrlistTimes(path string, times []Timespec, flags int) error {

	// used on Darwin for UtimesNano

	return ENOSYS

}

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 Stat(path string, st *Stat_t) (err error) {

	var oldStat stat_freebsd11_t

	if supportsABI(_ino64First) {

		return fstatat_freebsd12(AT_FDCWD, path, st, 0)

	}

	err = stat(path, &oldStat)

	if err != nil {

		return err

	}

	st.convertFrom(&oldStat)

	return nil

}

func Lstat(path string, st *Stat_t) (err error) {

	var oldStat stat_freebsd11_t

	if supportsABI(_ino64First) {

		return fstatat_freebsd12(AT_FDCWD, path, st, AT_SYMLINK_NOFOLLOW)

	}

	err = lstat(path, &oldStat)

	if err != nil {

		return err

	}

	st.convertFrom(&oldStat)

	return nil

}

func Fstat(fd int, st *Stat_t) (err error) {

	var oldStat stat_freebsd11_t

	if supportsABI(_ino64First) {

		return fstat_freebsd12(fd, st)

	}

	err = fstat(fd, &oldStat)

	if err != nil {

		return err

	}

	st.convertFrom(&oldStat)

	return nil

}

func Fstatat(fd int, path string, st *Stat_t, flags int) (err error) {

	var oldStat stat_freebsd11_t

	if supportsABI(_ino64First) {

		return fstatat_freebsd12(fd, path, st, flags)

	}

	err = fstatat(fd, path, &oldStat, flags)

	if err != nil {

		return err

	}

	st.convertFrom(&oldStat)

	return nil

}

func Statfs(path string, st *Statfs_t) (err error) {

	var oldStatfs statfs_freebsd11_t

	if supportsABI(_ino64First) {

		return statfs_freebsd12(path, st)

	}

	err = statfs(path, &oldStatfs)

	if err != nil {

		return err

	}

	st.convertFrom(&oldStatfs)

	return nil

}

func Fstatfs(fd int, st *Statfs_t) (err error) {

	var oldStatfs statfs_freebsd11_t

	if supportsABI(_ino64First) {

		return fstatfs_freebsd12(fd, st)

	}

	err = fstatfs(fd, &oldStatfs)

	if err != nil {

		return err

	}

	st.convertFrom(&oldStatfs)

	return nil

}

func Getdents(fd int, buf []byte) (n int, err error) {

	return Getdirentries(fd, buf, nil)

}

func Getdirentries(fd int, buf []byte, basep *uintptr) (n int, err error) {

	if supportsABI(_ino64First) {

		if basep == nil || unsafe.Sizeof(*basep) == 8 {

			return getdirentries_freebsd12(fd, buf, (*uint64)(unsafe.Pointer(basep)))

		}

		// The freebsd12 syscall needs a 64-bit base. On 32-bit machines

		// we can't just use the basep passed in. See #32498.

		var base uint64 = uint64(*basep)

		n, err = getdirentries_freebsd12(fd, buf, &base)

		*basep = uintptr(base)

		if base>>32 != 0 {

			// We can't stuff the base back into a uintptr, so any

			// future calls would be suspect. Generate an error.

			// EIO is allowed by getdirentries.

			err = EIO

		}

		return

	}

	// The old syscall entries are smaller than the new. Use 1/4 of the original

	// buffer size rounded up to DIRBLKSIZ (see /usr/src/lib/libc/sys/getdirentries.c).

	oldBufLen := roundup(len(buf)/4, _dirblksiz)

	oldBuf := make([]byte, oldBufLen)

	n, err = getdirentries(fd, oldBuf, basep)

	if err == nil && n > 0 {

		n = convertFromDirents11(buf, oldBuf[:n])

	}

	return

}

func Mknod(path string, mode uint32, dev uint64) (err error) {

	var oldDev int

	if supportsABI(_ino64First) {

		return mknodat_freebsd12(AT_FDCWD, path, mode, dev)

	}

	oldDev = int(dev)

	return mknod(path, mode, oldDev)

}

func Mknodat(fd int, path string, mode uint32, dev uint64) (err error) {

	var oldDev int

	if supportsABI(_ino64First) {

		return mknodat_freebsd12(fd, path, mode, dev)

	}

	oldDev = int(dev)

	return mknodat(fd, path, mode, oldDev)

}

// round x to the nearest multiple of y, larger or equal to x.