// +build linux

package namespaces

import (
	"os"
	"syscall"

	"github.com/docker/libcontainer/configs"
)

type initError struct {
	Message string `json:"message,omitempty"`
}

func (i initError) Error() string {
	return i.Message
}

var namespaceInfo = map[string]int{
	"NEWNET":  syscall.CLONE_NEWNET,
	"NEWNS":   syscall.CLONE_NEWNS,
	"NEWUSER": syscall.CLONE_NEWUSER,
	"NEWIPC":  syscall.CLONE_NEWIPC,
	"NEWUTS":  syscall.CLONE_NEWUTS,
	"NEWPID":  syscall.CLONE_NEWPID,
}

// New returns a newly initialized Pipe for communication between processes
func newInitPipe() (parent *os.File, child *os.File, err error) {
	fds, err := syscall.Socketpair(syscall.AF_LOCAL, syscall.SOCK_STREAM|syscall.SOCK_CLOEXEC, 0)
	if err != nil {
		return nil, nil, err
	}
	return os.NewFile(uintptr(fds[1]), "parent"), os.NewFile(uintptr(fds[0]), "child"), nil
}

// GetNamespaceFlags parses the container's Namespaces options to set the correct
// flags on clone, unshare, and setns
func GetNamespaceFlags(namespaces []configs.Namespace) (flag int) {
	for _, v := range namespaces {
		flag |= namespaceInfo[v.Name]
	}
	return flag
}