runc/tty.go

100 lines
2.0 KiB
Go

// +build linux
package main
import (
"io"
"os"
"github.com/docker/docker/pkg/term"
"github.com/opencontainers/runc/libcontainer"
)
// newTty creates a new pty for use with the container. If a tty is not to be
// created for the process, pipes are created so that the TTY of the parent
// process are not inherited by the container.
func newTty(create bool, p *libcontainer.Process, rootuid int) (*tty, error) {
if create {
return createTty(p, rootuid)
}
return createStdioPipes(p)
}
// setup standard pipes so that the TTY of the calling runc process
// is not inherited by the container.
func createStdioPipes(p *libcontainer.Process) (*tty, error) {
t := &tty{}
r, w, err := os.Pipe()
if err != nil {
return nil, err
}
go io.Copy(w, os.Stdin)
t.closers = append(t.closers, w)
p.Stdin = r
if r, w, err = os.Pipe(); err != nil {
return nil, err
}
go io.Copy(os.Stdout, r)
p.Stdout = w
t.closers = append(t.closers, r)
if r, w, err = os.Pipe(); err != nil {
return nil, err
}
go io.Copy(os.Stderr, r)
p.Stderr = w
t.closers = append(t.closers, r)
return t, nil
}
func createTty(p *libcontainer.Process, rootuid int) (*tty, error) {
console, err := p.NewConsole(rootuid)
if err != nil {
return nil, err
}
go io.Copy(console, os.Stdin)
go io.Copy(os.Stdout, console)
state, err := term.SetRawTerminal(os.Stdin.Fd())
if err != nil {
return nil, err
}
t := &tty{
console: console,
state: state,
closers: []io.Closer{
console,
},
}
p.Stderr = nil
p.Stdout = nil
p.Stdin = nil
return t, nil
}
type tty struct {
console libcontainer.Console
state *term.State
closers []io.Closer
}
func (t *tty) Close() error {
for _, c := range t.closers {
c.Close()
}
if t.state != nil {
term.RestoreTerminal(os.Stdin.Fd(), t.state)
}
return nil
}
func (t *tty) resize() error {
if t.console == nil {
return nil
}
ws, err := term.GetWinsize(os.Stdin.Fd())
if err != nil {
return err
}
return term.SetWinsize(t.console.Fd(), ws)
}