use tcell via porting over code from awesome-gocui

vendor/github.com/jesseduffield/gocui/gui_others.go

@@ -0,0 +1,60 @@
+// Copyright 2014 The gocui Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !windows
+
+package gocui
+
+import (
+	"os"
+	"os/signal"
+	"syscall"
+	"unsafe"
+
+	"github.com/go-errors/errors"
+)
+
+// getTermWindowSize is get terminal window size on linux or unix.
+// When gocui run inside the docker contaienr need to check and get the window size.
+func (g *Gui) getTermWindowSize() (int, int, error) {
+	var sz struct {
+		rows uint16
+		cols uint16
+		_    [2]uint16 // to match underlying syscall; see https://github.com/awesome-gocui/gocui/issues/33
+	}
+
+	var termw, termh int
+
+	out, err := os.OpenFile("/dev/tty", os.O_RDWR, 0)
+	if err != nil {
+		return 0, 0, err
+	}
+	defer out.Close()
+
+	signalCh := make(chan os.Signal, 1)
+	signal.Notify(signalCh, syscall.SIGWINCH, syscall.SIGINT)
+
+	for {
+		_, _, _ = syscall.Syscall(syscall.SYS_IOCTL,
+			out.Fd(), uintptr(syscall.TIOCGWINSZ), uintptr(unsafe.Pointer(&sz)))
+
+		// check terminal window size
+		termw, termh = int(sz.cols), int(sz.rows)
+		if termw > 0 && termh > 0 {
+			return termw, termh, nil
+		}
+
+		select {
+		case signal := <-signalCh:
+			switch signal {
+			// when the terminal window size is changed
+			case syscall.SIGWINCH:
+				continue
+			// ctrl + c to cancel
+			case syscall.SIGINT:
+				return 0, 0, errors.New("stop to get term window size")
+			}
+		}
+	}
+}