route/vendor/github.com/kr/pty/util.go

65 lines
1.5 KiB
Go

// +build !windows
package pty
import (
"os"
"syscall"
"unsafe"
)
// InheritSize applies the terminal size of master to slave. This should be run
// in a signal handler for syscall.SIGWINCH to automatically resize the slave when
// the master receives a window size change notification.
func InheritSize(master, slave *os.File) error {
size, err := GetsizeFull(master)
if err != nil {
return err
}
err = Setsize(slave, size)
if err != nil {
return err
}
return nil
}
// Setsize resizes t to s.
func Setsize(t *os.File, ws *Winsize) error {
return windowRectCall(ws, t.Fd(), syscall.TIOCSWINSZ)
}
// GetsizeFull returns the full terminal size description.
func GetsizeFull(t *os.File) (size *Winsize, err error) {
var ws Winsize
err = windowRectCall(&ws, t.Fd(), syscall.TIOCGWINSZ)
return &ws, err
}
// Getsize returns the number of rows (lines) and cols (positions
// in each line) in terminal t.
func Getsize(t *os.File) (rows, cols int, err error) {
ws, err := GetsizeFull(t)
return int(ws.Rows), int(ws.Cols), err
}
// Winsize describes the terminal size.
type Winsize struct {
Rows uint16 // ws_row: Number of rows (in cells)
Cols uint16 // ws_col: Number of columns (in cells)
X uint16 // ws_xpixel: Width in pixels
Y uint16 // ws_ypixel: Height in pixels
}
func windowRectCall(ws *Winsize, fd, a2 uintptr) error {
_, _, errno := syscall.Syscall(
syscall.SYS_IOCTL,
fd,
a2,
uintptr(unsafe.Pointer(ws)),
)
if errno != 0 {
return syscall.Errno(errno)
}
return nil
}