github.com/dolfly/pty@v1.2.1/pty_darwin.go (about)

     1  //go:build darwin
     2  //+build darwin
     3  
     4  package pty
     5  
     6  import (
     7  	"errors"
     8  	"os"
     9  	"syscall"
    10  	"unsafe"
    11  )
    12  
    13  func open() (pty, tty *os.File, err error) {
    14  	pFD, err := syscall.Open("/dev/ptmx", syscall.O_RDWR|syscall.O_CLOEXEC, 0)
    15  	if err != nil {
    16  		return nil, nil, err
    17  	}
    18  	p := os.NewFile(uintptr(pFD), "/dev/ptmx")
    19  	// In case of error after this point, make sure we close the ptmx fd.
    20  	defer func() {
    21  		if err != nil {
    22  			_ = p.Close() // Best effort.
    23  		}
    24  	}()
    25  
    26  	sname, err := ptsname(p)
    27  	if err != nil {
    28  		return nil, nil, err
    29  	}
    30  
    31  	if err := grantpt(p); err != nil {
    32  		return nil, nil, err
    33  	}
    34  
    35  	if err := unlockpt(p); err != nil {
    36  		return nil, nil, err
    37  	}
    38  
    39  	t, err := os.OpenFile(sname, os.O_RDWR|syscall.O_NOCTTY, 0)
    40  	if err != nil {
    41  		return nil, nil, err
    42  	}
    43  	return p, t, nil
    44  }
    45  
    46  func ptsname(f *os.File) (string, error) {
    47  	n := make([]byte, _IOC_PARM_LEN(syscall.TIOCPTYGNAME))
    48  
    49  	err := ioctl(f.Fd(), syscall.TIOCPTYGNAME, uintptr(unsafe.Pointer(&n[0])))
    50  	if err != nil {
    51  		return "", err
    52  	}
    53  
    54  	for i, c := range n {
    55  		if c == 0 {
    56  			return string(n[:i]), nil
    57  		}
    58  	}
    59  	return "", errors.New("TIOCPTYGNAME string not NUL-terminated")
    60  }
    61  
    62  func grantpt(f *os.File) error {
    63  	return ioctl(f.Fd(), syscall.TIOCPTYGRANT, 0)
    64  }
    65  
    66  func unlockpt(f *os.File) error {
    67  	return ioctl(f.Fd(), syscall.TIOCPTYUNLK, 0)
    68  }