6daf56799f
Remove logging for now because it is complicating things Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
58 lines
1.7 KiB
Go
58 lines
1.7 KiB
Go
package system
|
|
|
|
import (
|
|
"fmt"
|
|
"os"
|
|
"syscall"
|
|
"unsafe"
|
|
)
|
|
|
|
// Unlockpt unlocks the slave pseudoterminal device corresponding to the master pseudoterminal referred to by f.
|
|
// Unlockpt should be called before opening the slave side of a pseudoterminal.
|
|
func Unlockpt(f *os.File) error {
|
|
var u int
|
|
return Ioctl(f.Fd(), syscall.TIOCSPTLCK, uintptr(unsafe.Pointer(&u)))
|
|
}
|
|
|
|
// Ptsname retrieves the name of the first available pts for the given master.
|
|
func Ptsname(f *os.File) (string, error) {
|
|
var n int
|
|
|
|
if err := Ioctl(f.Fd(), syscall.TIOCGPTN, uintptr(unsafe.Pointer(&n))); err != nil {
|
|
return "", err
|
|
}
|
|
return fmt.Sprintf("/dev/pts/%d", n), nil
|
|
}
|
|
|
|
// CreateMasterAndConsole will open /dev/ptmx on the host and retreive the
|
|
// pts name for use as the pty slave inside the container
|
|
func CreateMasterAndConsole() (*os.File, string, error) {
|
|
master, err := os.OpenFile("/dev/ptmx", syscall.O_RDWR|syscall.O_NOCTTY|syscall.O_CLOEXEC, 0)
|
|
if err != nil {
|
|
return nil, "", err
|
|
}
|
|
console, err := Ptsname(master)
|
|
if err != nil {
|
|
return nil, "", err
|
|
}
|
|
if err := Unlockpt(master); err != nil {
|
|
return nil, "", err
|
|
}
|
|
return master, console, nil
|
|
}
|
|
|
|
// OpenPtmx opens /dev/ptmx, i.e. the PTY master.
|
|
func OpenPtmx() (*os.File, error) {
|
|
// O_NOCTTY and O_CLOEXEC are not present in os package so we use the syscall's one for all.
|
|
return os.OpenFile("/dev/ptmx", syscall.O_RDONLY|syscall.O_NOCTTY|syscall.O_CLOEXEC, 0)
|
|
}
|
|
|
|
// OpenTerminal is a clone of os.OpenFile without the O_CLOEXEC
|
|
// used to open the pty slave inside the container namespace
|
|
func OpenTerminal(name string, flag int) (*os.File, error) {
|
|
r, e := syscall.Open(name, flag, 0)
|
|
if e != nil {
|
|
return nil, &os.PathError{"open", name, e}
|
|
}
|
|
return os.NewFile(uintptr(r), name), nil
|
|
}
|