tcell/tscreen_unix.go

134 lines
3.4 KiB
Go

// Copyright 2021 The TCell Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use file except in compliance with the License.
// You may obtain a copy of the license at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris zos
package tcell
import (
"errors"
"os"
"os/signal"
"syscall"
"golang.org/x/term"
)
// engage is used to place the terminal in raw mode and establish screen size, etc.
// Thing of this is as tcell "engaging" the clutch, as it's going to be driving the
// terminal interface.
func (t *tScreen) engage() error {
t.Lock()
defer t.Unlock()
if t.stopQ != nil {
return errors.New("already engaged")
}
if _, err := term.MakeRaw(int(t.in.Fd())); err != nil {
return err
}
if w, h, err := term.GetSize(int(t.in.Fd())); err == nil && w != 0 && h != 0 {
t.cells.Resize(w, h)
}
stopQ := make(chan struct{})
t.stopQ = stopQ
t.nonBlocking(false)
t.enableMouse(t.mouseFlags)
t.enablePasting(t.pasteEnabled)
signal.Notify(t.sigwinch, syscall.SIGWINCH)
ti := t.ti
t.TPuts(ti.EnterCA)
t.TPuts(ti.EnterKeypad)
t.TPuts(ti.HideCursor)
t.TPuts(ti.EnableAcs)
t.TPuts(ti.Clear)
t.wg.Add(2)
go t.inputLoop(stopQ)
go t.mainLoop(stopQ)
return nil
}
// disengage is used to release the terminal back to support from the caller.
// Think of this as tcell disengaging the clutch, so that another application
// can take over the terminal interface. This restores the TTY mode that was
// present when the application was first started.
func (t *tScreen) disengage() {
t.Lock()
t.nonBlocking(true)
stopQ := t.stopQ
t.stopQ = nil
close(stopQ)
t.Unlock()
// wait for everything to shut down
t.wg.Wait()
signal.Stop(t.sigwinch)
// put back normal blocking mode
t.nonBlocking(false)
// shutdown the screen and disable special modes (e.g. mouse and bracketed paste)
ti := t.ti
t.cells.Resize(0, 0)
t.TPuts(ti.ShowCursor)
t.TPuts(ti.AttrOff)
t.TPuts(ti.Clear)
t.TPuts(ti.ExitCA)
t.TPuts(ti.ExitKeypad)
t.enableMouse(0)
t.enablePasting(false)
// restore the termios that we were started with
_ = term.Restore(int(t.in.Fd()), t.saved)
}
// initialize is used at application startup, and sets up the initial values
// including file descriptors used for terminals and saving the initial state
// so that it can be restored when the application terminates.
func (t *tScreen) initialize() error {
var err error
t.out = os.Stdout
if t.in, err = os.Open("/dev/tty"); err != nil {
return err
}
t.saved, err = term.GetState(int(t.in.Fd()))
if err == nil {
return nil
}
return nil
}
// finalize is used to at application shutdown, and restores the terminal
// to it's initial state. It should not be called more than once.
func (t *tScreen) finalize() {
t.disengage()
}
// getWinSize is called to obtain the terminal dimensions.
func (t *tScreen) getWinSize() (int, int, error) {
return term.GetSize(int(t.in.Fd()))
}
// Beep emits a beep to the terminal.
func (t *tScreen) Beep() error {
t.writeString(string(byte(7)))
return nil
}