server: terminal width should fallback to 80x25. (#1895)

Some environments might disable access to `/dev/tty`, fall
back to '80' in such scenarios.

Move to 'cheggaaa/pb' package for better cross platform
support on fetching terminal width.

Fixes #1891

vendor/github.com/cheggaaa/pb/pb_win.go

@@ -0,0 +1,141 @@
+// +build windows
+
+package pb
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"sync"
+	"syscall"
+	"unsafe"
+)
+
+var tty = os.Stdin
+
+var (
+	kernel32 = syscall.NewLazyDLL("kernel32.dll")
+
+	// GetConsoleScreenBufferInfo retrieves information about the
+	// specified console screen buffer.
+	// http://msdn.microsoft.com/en-us/library/windows/desktop/ms683171(v=vs.85).aspx
+	procGetConsoleScreenBufferInfo = kernel32.NewProc("GetConsoleScreenBufferInfo")
+
+	// GetConsoleMode retrieves the current input mode of a console's
+	// input buffer or the current output mode of a console screen buffer.
+	// https://msdn.microsoft.com/en-us/library/windows/desktop/ms683167(v=vs.85).aspx
+	getConsoleMode = kernel32.NewProc("GetConsoleMode")
+
+	// SetConsoleMode sets the input mode of a console's input buffer
+	// or the output mode of a console screen buffer.
+	// https://msdn.microsoft.com/en-us/library/windows/desktop/ms686033(v=vs.85).aspx
+	setConsoleMode = kernel32.NewProc("SetConsoleMode")
+
+	// SetConsoleCursorPosition sets the cursor position in the
+	// specified console screen buffer.
+	// https://msdn.microsoft.com/en-us/library/windows/desktop/ms686025(v=vs.85).aspx
+	setConsoleCursorPosition = kernel32.NewProc("SetConsoleCursorPosition")
+)
+
+type (
+	// Defines the coordinates of the upper left and lower right corners
+	// of a rectangle.
+	// See
+	// http://msdn.microsoft.com/en-us/library/windows/desktop/ms686311(v=vs.85).aspx
+	smallRect struct {
+		Left, Top, Right, Bottom int16
+	}
+
+	// Defines the coordinates of a character cell in a console screen
+	// buffer. The origin of the coordinate system (0,0) is at the top, left cell
+	// of the buffer.
+	// See
+	// http://msdn.microsoft.com/en-us/library/windows/desktop/ms682119(v=vs.85).aspx
+	coordinates struct {
+		X, Y int16
+	}
+
+	word int16
+
+	// Contains information about a console screen buffer.
+	// http://msdn.microsoft.com/en-us/library/windows/desktop/ms682093(v=vs.85).aspx
+	consoleScreenBufferInfo struct {
+		dwSize              coordinates
+		dwCursorPosition    coordinates
+		wAttributes         word
+		srWindow            smallRect
+		dwMaximumWindowSize coordinates
+	}
+)
+
+// terminalWidth returns width of the terminal.
+func terminalWidth() (width int, err error) {
+	var info consoleScreenBufferInfo
+	_, _, e := syscall.Syscall(procGetConsoleScreenBufferInfo.Addr(), 2, uintptr(syscall.Stdout), uintptr(unsafe.Pointer(&info)), 0)
+	if e != 0 {
+		return 0, error(e)
+	}
+	return int(info.dwSize.X) - 1, nil
+}
+
+func getCursorPos() (pos coordinates, err error) {
+	var info consoleScreenBufferInfo
+	_, _, e := syscall.Syscall(procGetConsoleScreenBufferInfo.Addr(), 2, uintptr(syscall.Stdout), uintptr(unsafe.Pointer(&info)), 0)
+	if e != 0 {
+		return info.dwCursorPosition, error(e)
+	}
+	return info.dwCursorPosition, nil
+}
+
+func setCursorPos(pos coordinates) error {
+	_, _, e := syscall.Syscall(setConsoleCursorPosition.Addr(), 2, uintptr(syscall.Stdout), uintptr(uint32(uint16(pos.Y))<<16|uint32(uint16(pos.X))), 0)
+	if e != 0 {
+		return error(e)
+	}
+	return nil
+}
+
+var ErrPoolWasStarted = errors.New("Bar pool was started")
+
+var echoLocked bool
+var echoLockMutex sync.Mutex
+
+var oldState word
+
+func lockEcho() (quit chan int, err error) {
+	echoLockMutex.Lock()
+	defer echoLockMutex.Unlock()
+	if echoLocked {
+		err = ErrPoolWasStarted
+		return
+	}
+	echoLocked = true
+
+	if _, _, e := syscall.Syscall(getConsoleMode.Addr(), 2, uintptr(syscall.Stdout), uintptr(unsafe.Pointer(&oldState)), 0); e != 0 {
+		err = fmt.Errorf("Can't get terminal settings: %v", e)
+		return
+	}
+
+	newState := oldState
+	const ENABLE_ECHO_INPUT = 0x0004
+	const ENABLE_LINE_INPUT = 0x0002
+	newState = newState & (^(ENABLE_LINE_INPUT | ENABLE_ECHO_INPUT))
+	if _, _, e := syscall.Syscall(setConsoleMode.Addr(), 2, uintptr(syscall.Stdout), uintptr(newState), 0); e != 0 {
+		err = fmt.Errorf("Can't set terminal settings: %v", e)
+		return
+	}
+	return
+}
+
+func unlockEcho() (err error) {
+	echoLockMutex.Lock()
+	defer echoLockMutex.Unlock()
+	if !echoLocked {
+		return
+	}
+	echoLocked = false
+	if _, _, e := syscall.Syscall(setConsoleMode.Addr(), 2, uintptr(syscall.Stdout), uintptr(oldState), 0); e != 0 {
+		err = fmt.Errorf("Can't set terminal settings")
+	}
+	return
+}