// Copyright 2009 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.

// +build amd64,linux

package unix

import "syscall"

//sys	Dup2(oldfd int, newfd int) (err error)
//sys	EpollWait(epfd int, events []EpollEvent, msec int) (n int, err error)
//sys	Fadvise(fd int, offset int64, length int64, advice int) (err error) = SYS_FADVISE64
//sys	Fchown(fd int, uid int, gid int) (err error)
//sys	Fstat(fd int, stat *Stat_t) (err error)
//sys	Fstatfs(fd int, buf *Statfs_t) (err error)
//sys	Ftruncate(fd int, length int64) (err error)
//sysnb	Getegid() (egid int)
//sysnb	Geteuid() (euid int)
//sysnb	Getgid() (gid int)
//sysnb	Getrlimit(resource int, rlim *Rlimit) (err error)
//sysnb	Getuid() (uid int)
//sysnb	InotifyInit() (fd int, err error)
//sys	Ioperm(from int, num int, on int) (err error)
//sys	Iopl(level int) (err error)
//sys	Lchown(path string, uid int, gid int) (err error)
//sys	Listen(s int, n int) (err error)
//sys	Lstat(path string, stat *Stat_t) (err error)
//sys	Pause() (err error)
//sys	Pread(fd int, p []byte, offset int64) (n int, err error) = SYS_PREAD64
//sys	Pwrite(fd int, p []byte, offset int64) (n int, err error) = SYS_PWRITE64
//sys	Seek(fd int, offset int64, whence int) (off int64, err error) = SYS_LSEEK
//sys	Select(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timeval) (n int, err error)
//sys	sendfile(outfd int, infd int, offset *int64, count int) (written int, err error)
//sys	Setfsgid(gid int) (err error)
//sys	Setfsuid(uid int) (err error)
//sysnb	Setregid(rgid int, egid int) (err error)
//sysnb	Setresgid(rgid int, egid int, sgid int) (err error)
//sysnb	Setresuid(ruid int, euid int, suid int) (err error)
//sysnb	Setrlimit(resource int, rlim *Rlimit) (err error)
//sysnb	Setreuid(ruid int, euid int) (err error)
//sys	Shutdown(fd int, how int) (err error)
//sys	Splice(rfd int, roff *int64, wfd int, woff *int64, len int, flags int) (n int64, err error)
//sys	Stat(path string, stat *Stat_t) (err error)
//sys	Statfs(path string, buf *Statfs_t) (err error)
//sys	SyncFileRange(fd int, off int64, n int64, flags int) (err error)
//sys	Truncate(path string, length int64) (err error)
//sys	accept(s int, rsa *RawSockaddrAny, addrlen *_Socklen) (fd int, err error)
//sys	accept4(s int, rsa *RawSockaddrAny, addrlen *_Socklen, flags int) (fd int, err error)
//sys	bind(s int, addr unsafe.Pointer, addrlen _Socklen) (err error)
//sys	connect(s int, addr unsafe.Pointer, addrlen _Socklen) (err error)
//sysnb	getgroups(n int, list *_Gid_t) (nn int, err error)
//sysnb	setgroups(n int, list *_Gid_t) (err error)
//sys	getsockopt(s int, level int, name int, val unsafe.Pointer, vallen *_Socklen) (err error)
//sys	setsockopt(s int, level int, name int, val unsafe.Pointer, vallen uintptr) (err error)
//sysnb	socket(domain int, typ int, proto int) (fd int, err error)
//sysnb	socketpair(domain int, typ int, proto int, fd *[2]int32) (err error)
//sysnb	getpeername(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error)
//sysnb	getsockname(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error)
//sys	recvfrom(fd int, p []byte, flags int, from *RawSockaddrAny, fromlen *_Socklen) (n int, err error)
//sys	sendto(s int, buf []byte, flags int, to unsafe.Pointer, addrlen _Socklen) (err error)
//sys	recvmsg(s int, msg *Msghdr, flags int) (n int, err error)
//sys	sendmsg(s int, msg *Msghdr, flags int) (n int, err error)
//sys	mmap(addr uintptr, length uintptr, prot int, flags int, fd int, offset int64) (xaddr uintptr, err error)

//go:noescape
func gettimeofday(tv *Timeval) (err syscall.Errno)

func Gettimeofday(tv *Timeval) (err error) {
	errno := gettimeofday(tv)
	if errno != 0 {
		return errno
	}
	return nil
}

func Getpagesize() int { return 4096 }

func Time(t *Time_t) (tt Time_t, err error) {
	var tv Timeval
	errno := gettimeofday(&tv)
	if errno != 0 {
		return 0, errno
	}
	if t != nil {
		*t = Time_t(tv.Sec)
	}
	return Time_t(tv.Sec), nil
}

//sys	Utime(path string, buf *Utimbuf) (err error)

func TimespecToNsec(ts Timespec) int64 { return int64(ts.Sec)*1e9 + int64(ts.Nsec) }

func NsecToTimespec(nsec int64) (ts Timespec) {
	ts.Sec = nsec / 1e9
	ts.Nsec = nsec % 1e9
	return
}

func NsecToTimeval(nsec int64) (tv Timeval) {
	nsec += 999 // round up to microsecond
	tv.Sec = nsec / 1e9
	tv.Usec = nsec % 1e9 / 1e3
	return
}

//sysnb	pipe(p *[2]_C_int) (err error)

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

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

func Pipe2(p []int, flags int) (err 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
}

func (r *PtraceRegs) PC() uint64 { return r.Rip }

func (r *PtraceRegs) SetPC(pc uint64) { r.Rip = pc }

func (iov *Iovec) SetLen(length int) {
	iov.Len = uint64(length)
}

func (msghdr *Msghdr) SetControllen(length int) {
	msghdr.Controllen = uint64(length)
}

func (cmsg *Cmsghdr) SetLen(length int) {
	cmsg.Len = uint64(length)
}

//sys	poll(fds *PollFd, nfds int, timeout int) (n int, err error)

func Poll(fds []PollFd, timeout int) (n int, err error) {
	if len(fds) == 0 {
		return poll(nil, 0, timeout)
	}
	return poll(&fds[0], len(fds), timeout)
}
