1//go:build dragonfly
2//+build dragonfly
3
4package pty
5
6import (
7	"errors"
8	"os"
9	"strings"
10	"syscall"
11	"unsafe"
12)
13
14// same code as pty_darwin.go
15func open() (pty, tty *os.File, err error) {
16	p, err := os.OpenFile("/dev/ptmx", os.O_RDWR, 0)
17	if err != nil {
18		return nil, nil, err
19	}
20	// In case of error after this point, make sure we close the ptmx fd.
21	defer func() {
22		if err != nil {
23			_ = p.Close() // Best effort.
24		}
25	}()
26
27	sname, err := ptsname(p)
28	if err != nil {
29		return nil, nil, err
30	}
31
32	if err := grantpt(p); err != nil {
33		return nil, nil, err
34	}
35
36	if err := unlockpt(p); err != nil {
37		return nil, nil, err
38	}
39
40	t, err := os.OpenFile(sname, os.O_RDWR, 0)
41	if err != nil {
42		return nil, nil, err
43	}
44	return p, t, nil
45}
46
47func grantpt(f *os.File) error {
48	_, err := isptmaster(f.Fd())
49	return err
50}
51
52func unlockpt(f *os.File) error {
53	_, err := isptmaster(f.Fd())
54	return err
55}
56
57func isptmaster(fd uintptr) (bool, error) {
58	err := ioctl(fd, syscall.TIOCISPTMASTER, 0)
59	return err == nil, err
60}
61
62var (
63	emptyFiodgnameArg fiodgnameArg
64	ioctl_FIODNAME    = _IOW('f', 120, unsafe.Sizeof(emptyFiodgnameArg))
65)
66
67func ptsname(f *os.File) (string, error) {
68	name := make([]byte, _C_SPECNAMELEN)
69	fa := fiodgnameArg{Name: (*byte)(unsafe.Pointer(&name[0])), Len: _C_SPECNAMELEN, Pad_cgo_0: [4]byte{0, 0, 0, 0}}
70
71	err := ioctl(f.Fd(), ioctl_FIODNAME, uintptr(unsafe.Pointer(&fa)))
72	if err != nil {
73		return "", err
74	}
75
76	for i, c := range name {
77		if c == 0 {
78			s := "/dev/" + string(name[:i])
79			return strings.Replace(s, "ptm", "pts", -1), nil
80		}
81	}
82	return "", errors.New("TIOCPTYGNAME string not NUL-terminated")
83}
84