Move utility package 'term' to pkg/term

term/term.go

@@ -0,0 +1,103 @@
+package term
+
+import (
+	"errors"
+	"os"
+	"os/signal"
+	"syscall"
+	"unsafe"
+)
+
+var (
+	ErrInvalidState = errors.New("Invalid terminal state")
+)
+
+type State struct {
+	termios Termios
+}
+
+type Winsize struct {
+	Height uint16
+	Width  uint16
+	x      uint16
+	y      uint16
+}
+
+func GetWinsize(fd uintptr) (*Winsize, error) {
+	ws := &Winsize{}
+	_, _, err := syscall.Syscall(syscall.SYS_IOCTL, fd, uintptr(syscall.TIOCGWINSZ), uintptr(unsafe.Pointer(ws)))
+	// Skipp errno = 0
+	if err == 0 {
+		return ws, nil
+	}
+	return ws, err
+}
+
+func SetWinsize(fd uintptr, ws *Winsize) error {
+	_, _, err := syscall.Syscall(syscall.SYS_IOCTL, fd, uintptr(syscall.TIOCSWINSZ), uintptr(unsafe.Pointer(ws)))
+	// Skipp errno = 0
+	if err == 0 {
+		return nil
+	}
+	return err
+}
+
+// IsTerminal returns true if the given file descriptor is a terminal.
+func IsTerminal(fd uintptr) bool {
+	var termios Termios
+	_, _, err := syscall.Syscall(syscall.SYS_IOCTL, fd, uintptr(getTermios), uintptr(unsafe.Pointer(&termios)))
+	return err == 0
+}
+
+// Restore restores the terminal connected to the given file descriptor to a
+// previous state.
+func RestoreTerminal(fd uintptr, state *State) error {
+	if state == nil {
+		return ErrInvalidState
+	}
+	_, _, err := syscall.Syscall(syscall.SYS_IOCTL, fd, uintptr(setTermios), uintptr(unsafe.Pointer(&state.termios)))
+	if err != 0 {
+		return err
+	}
+	return nil
+}
+
+func SaveState(fd uintptr) (*State, error) {
+	var oldState State
+	if _, _, err := syscall.Syscall(syscall.SYS_IOCTL, fd, getTermios, uintptr(unsafe.Pointer(&oldState.termios))); err != 0 {
+		return nil, err
+	}
+
+	return &oldState, nil
+}
+
+func DisableEcho(fd uintptr, state *State) error {
+	newState := state.termios
+	newState.Lflag &^= syscall.ECHO
+
+	if _, _, err := syscall.Syscall(syscall.SYS_IOCTL, fd, setTermios, uintptr(unsafe.Pointer(&newState))); err != 0 {
+		return err
+	}
+	handleInterrupt(fd, state)
+	return nil
+}
+
+func SetRawTerminal(fd uintptr) (*State, error) {
+	oldState, err := MakeRaw(fd)
+	if err != nil {
+		return nil, err
+	}
+	handleInterrupt(fd, oldState)
+	return oldState, err
+}
+
+func handleInterrupt(fd uintptr, state *State) {
+	sigchan := make(chan os.Signal, 1)
+	signal.Notify(sigchan, os.Interrupt)
+
+	go func() {
+		_ = <-sigchan
+		RestoreTerminal(fd, state)
+		os.Exit(0)
+	}()
+}