// Copyright 2021 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.

// illumos system calls not present on Solaris.

//go:build amd64 && illumos

// +build amd64,illumos

package unix

import (

	"fmt"

	"runtime"

	"unsafe"

)

func bytes2iovec(bs [][]byte) []Iovec {

	iovecs := make([]Iovec, len(bs))

	for i, b := range bs {

		iovecs[i].SetLen(len(b))

		if len(b) > 0 {

			// somehow Iovec.Base on illumos is (*int8), not (*byte)

			iovecs[i].Base = (*int8)(unsafe.Pointer(&b[0]))

		} else {

			iovecs[i].Base = (*int8)(unsafe.Pointer(&_zero))

		}

	}

	return iovecs

}

//sys	readv(fd int, iovs []Iovec) (n int, err error)

func Readv(fd int, iovs [][]byte) (n int, err error) {

	iovecs := bytes2iovec(iovs)

	n, err = readv(fd, iovecs)

	return n, err

}

//sys	preadv(fd int, iovs []Iovec, off int64) (n int, err error)

func Preadv(fd int, iovs [][]byte, off int64) (n int, err error) {

	iovecs := bytes2iovec(iovs)

	n, err = preadv(fd, iovecs, off)

	return n, err

}

//sys	writev(fd int, iovs []Iovec) (n int, err error)

func Writev(fd int, iovs [][]byte) (n int, err error) {

	iovecs := bytes2iovec(iovs)

	n, err = writev(fd, iovecs)

	return n, err

}

//sys	pwritev(fd int, iovs []Iovec, off int64) (n int, err error)

func Pwritev(fd int, iovs [][]byte, off int64) (n int, err error) {

	iovecs := bytes2iovec(iovs)

	n, err = pwritev(fd, iovecs, off)

	return n, err

}

//sys	accept4(s int, rsa *RawSockaddrAny, addrlen *_Socklen, flags int) (fd int, err error) = libsocket.accept4

func Accept4(fd int, 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	putmsg(fd int, clptr *strbuf, dataptr *strbuf, flags int) (err error)

func Putmsg(fd int, cl []byte, data []byte, flags int) (err error) {

	var clp, datap *strbuf

	if len(cl) > 0 {

		clp = &strbuf{

			Len: int32(len(cl)),

			Buf: (*int8)(unsafe.Pointer(&cl[0])),

		}

	}

	if len(data) > 0 {

		datap = &strbuf{

			Len: int32(len(data)),

			Buf: (*int8)(unsafe.Pointer(&data[0])),

		}

	}

	return putmsg(fd, clp, datap, flags)

}

//sys	getmsg(fd int, clptr *strbuf, dataptr *strbuf, flags *int) (err error)

func Getmsg(fd int, cl []byte, data []byte) (retCl []byte, retData []byte, flags int, err error) {

	var clp, datap *strbuf

	if len(cl) > 0 {

		clp = &strbuf{

			Maxlen: int32(len(cl)),

			Buf:    (*int8)(unsafe.Pointer(&cl[0])),

		}

	}

	if len(data) > 0 {

		datap = &strbuf{

			Maxlen: int32(len(data)),

			Buf:    (*int8)(unsafe.Pointer(&data[0])),

		}

	}

	if err = getmsg(fd, clp, datap, &flags); err != nil {

		return nil, nil, 0, err

	}

	if len(cl) > 0 {

		retCl = cl[:clp.Len]

	}

	if len(data) > 0 {

		retData = data[:datap.Len]

	}

	return retCl, retData, flags, nil

}

func IoctlSetIntRetInt(fd int, req uint, arg int) (int, error) {

	return ioctlRet(fd, req, uintptr(arg))

}

func IoctlSetString(fd int, req uint, val string) error {

	bs := make([]byte, len(val)+1)

	copy(bs[:len(bs)-1], val)

	err := ioctl(fd, req, uintptr(unsafe.Pointer(&bs[0])))

	runtime.KeepAlive(&bs[0])

	return err

}

// Lifreq Helpers

func (l *Lifreq) SetName(name string) error {

	if len(name) >= len(l.Name) {

		return fmt.Errorf("name cannot be more than %d characters", len(l.Name)-1)

	}

	for i := range name {

		l.Name[i] = int8(name[i])

	}

	return nil

}

func (l *Lifreq) SetLifruInt(d int) {

	*(*int)(unsafe.Pointer(&l.Lifru[0])) = d

}

func (l *Lifreq) GetLifruInt() int {

	return *(*int)(unsafe.Pointer(&l.Lifru[0]))

}

func IoctlLifreq(fd int, req uint, l *Lifreq) error {

	return ioctl(fd, req, uintptr(unsafe.Pointer(l)))

}

// Strioctl Helpers

func (s *Strioctl) SetInt(i int) {

	s.Len = int32(unsafe.Sizeof(i))

	s.Dp = (*int8)(unsafe.Pointer(&i))

}

func IoctlSetStrioctlRetInt(fd int, req uint, s *Strioctl) (int, error) {

	return ioctlRet(fd, req, uintptr(unsafe.Pointer(s)))

}