//go:build linux
// +build linux

package xnet

import (
	"net"
	"os"
	"syscall"
)

// SetKeepAliveIdle sets the time (in seconds) the connection needs to remain
// idle before TCP starts sending keepalive probes.
func setAliveIdle(tcp *net.TCPConn, secs int) error {
	file, err := tcp.File()
	if err != nil {
		return err
	}
	fd := int(file.Fd())
	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd, syscall.IPPROTO_TCP, syscall.TCP_KEEPIDLE, secs))
}

// SetKeepAliveCount sets the maximum number of keepalive probes TCP should
// send before dropping the connection.
func setAliveCount(tcp *net.TCPConn, n int) error {
	file, err := tcp.File()
	if err != nil {
		return err
	}
	fd := int(file.Fd())
	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd, syscall.IPPROTO_TCP, syscall.TCP_KEEPCNT, n))
}

// SetKeepAliveInterval sets the time (in seconds) between individual keepalive
// probes.
func setAliveInterval(tcp *net.TCPConn, secs int) error {
	file, err := tcp.File()
	if err != nil {
		return err
	}
	fd := int(file.Fd())
	return os.NewSyscallError("setsockopt", syscall.SetsockoptInt(fd, syscall.IPPROTO_TCP, syscall.TCP_KEEPINTVL, secs))
}

func setNonblock(fd int) error {
	return os.NewSyscallError("setsockopt", syscall.SetNonblock(fd, true))

}