//go:build linux

package host

import (
	"github.com/carlosframework/platform/internal/hostbox"
	"golang.org/x/sys/unix"
	"path/filepath"
	"strings"
)

var claimContainmentAgentRoot = agentUnitCgroup
var claimContainmentInspect = inspectClaimContainment

func inspectClaimContainment(relative string) (hostbox.LaunchGroup, error) {
	if !filepath.IsLocal(relative) || filepath.Clean(relative) != relative || relative == "." {
		return hostbox.LaunchGroup{}, ErrClaimStopInventory
	}
	fd, err := unix.Open("/sys/fs/cgroup", unix.O_RDONLY|unix.O_DIRECTORY|unix.O_CLOEXEC|unix.O_NOFOLLOW, 0)
	if err != nil {
		return hostbox.LaunchGroup{}, err
	}
	for _, part := range strings.Split(relative, "/") {
		next, e := unix.Openat(fd, part, unix.O_RDONLY|unix.O_DIRECTORY|unix.O_CLOEXEC|unix.O_NOFOLLOW, 0)
		unix.Close(fd)
		if e != nil {
			return hostbox.LaunchGroup{}, e
		}
		fd = next
	}
	defer unix.Close(fd)
	var st unix.Stat_t
	if err = unix.Fstat(fd, &st); err != nil {
		return hostbox.LaunchGroup{}, err
	}
	return hostbox.LaunchGroup{RelativePath: relative, Device: uint64(st.Dev), Inode: st.Ino}, nil
}