DockerCLI/vendor/github.com/creack/pty/pty_solaris.go

153 lines
3.3 KiB
Go

//go:build solaris
// +build solaris
package pty
/* based on:
http://src.illumos.org/source/xref/illumos-gate/usr/src/lib/libc/port/gen/pt.c
*/
import (
"errors"
"os"
"strconv"
"syscall"
"unsafe"
)
func open() (pty, tty *os.File, err error) {
ptmxfd, err := syscall.Open("/dev/ptmx", syscall.O_RDWR|syscall.O_NOCTTY, 0)
if err != nil {
return nil, nil, err
}
p := os.NewFile(uintptr(ptmxfd), "/dev/ptmx")
// In case of error after this point, make sure we close the ptmx fd.
defer func() {
if err != nil {
_ = p.Close() // Best effort.
}
}()
sname, err := ptsname(p)
if err != nil {
return nil, nil, err
}
if err := grantpt(p); err != nil {
return nil, nil, err
}
if err := unlockpt(p); err != nil {
return nil, nil, err
}
ptsfd, err := syscall.Open(sname, os.O_RDWR|syscall.O_NOCTTY, 0)
if err != nil {
return nil, nil, err
}
t := os.NewFile(uintptr(ptsfd), sname)
// In case of error after this point, make sure we close the pts fd.
defer func() {
if err != nil {
_ = t.Close() // Best effort.
}
}()
// pushing terminal driver STREAMS modules as per pts(7)
for _, mod := range []string{"ptem", "ldterm", "ttcompat"} {
if err := streamsPush(t, mod); err != nil {
return nil, nil, err
}
}
return p, t, nil
}
func ptsname(f *os.File) (string, error) {
dev, err := ptsdev(f.Fd())
if err != nil {
return "", err
}
fn := "/dev/pts/" + strconv.FormatInt(int64(dev), 10)
if err := syscall.Access(fn, 0); err != nil {
return "", err
}
return fn, nil
}
func unlockpt(f *os.File) error {
istr := strioctl{
icCmd: UNLKPT,
icTimeout: 0,
icLen: 0,
icDP: nil,
}
return ioctl(f.Fd(), I_STR, uintptr(unsafe.Pointer(&istr)))
}
func minor(x uint64) uint64 { return x & 0377 }
func ptsdev(fd uintptr) (uint64, error) {
istr := strioctl{
icCmd: ISPTM,
icTimeout: 0,
icLen: 0,
icDP: nil,
}
if err := ioctl(fd, I_STR, uintptr(unsafe.Pointer(&istr))); err != nil {
return 0, err
}
var status syscall.Stat_t
if err := syscall.Fstat(int(fd), &status); err != nil {
return 0, err
}
return uint64(minor(status.Rdev)), nil
}
type ptOwn struct {
rUID int32
rGID int32
}
func grantpt(f *os.File) error {
if _, err := ptsdev(f.Fd()); err != nil {
return err
}
pto := ptOwn{
rUID: int32(os.Getuid()),
// XXX should first attempt to get gid of DEFAULT_TTY_GROUP="tty"
rGID: int32(os.Getgid()),
}
istr := strioctl{
icCmd: OWNERPT,
icTimeout: 0,
icLen: int32(unsafe.Sizeof(strioctl{})),
icDP: unsafe.Pointer(&pto),
}
if err := ioctl(f.Fd(), I_STR, uintptr(unsafe.Pointer(&istr))); err != nil {
return errors.New("access denied")
}
return nil
}
// streamsPush pushes STREAMS modules if not already done so.
func streamsPush(f *os.File, mod string) error {
buf := []byte(mod)
// XXX I_FIND is not returning an error when the module
// is already pushed even though truss reports a return
// value of 1. A bug in the Go Solaris syscall interface?
// XXX without this we are at risk of the issue
// https://www.illumos.org/issues/9042
// but since we are not using libc or XPG4.2, we should not be
// double-pushing modules
if err := ioctl(f.Fd(), I_FIND, uintptr(unsafe.Pointer(&buf[0]))); err != nil {
return nil
}
return ioctl(f.Fd(), I_PUSH, uintptr(unsafe.Pointer(&buf[0])))
}