vendor: github.com/nsf/termbox-go and dependencies for rclone ncdu

vendor/github.com/nsf/termbox-go/api.go

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+// +build !windows
+
+package termbox
+
+import "github.com/mattn/go-runewidth"
+import "fmt"
+import "os"
+import "os/signal"
+import "syscall"
+import "runtime"
+
+// public API
+
+// Initializes termbox library. This function should be called before any other functions.
+// After successful initialization, the library must be finalized using 'Close' function.
+//
+// Example usage:
+//      err := termbox.Init()
+//      if err != nil {
+//              panic(err)
+//      }
+//      defer termbox.Close()
+func Init() error {
+	var err error
+
+	out, err = os.OpenFile("/dev/tty", syscall.O_WRONLY, 0)
+	if err != nil {
+		return err
+	}
+	in, err = syscall.Open("/dev/tty", syscall.O_RDONLY, 0)
+	if err != nil {
+		return err
+	}
+
+	err = setup_term()
+	if err != nil {
+		return fmt.Errorf("termbox: error while reading terminfo data: %v", err)
+	}
+
+	signal.Notify(sigwinch, syscall.SIGWINCH)
+	signal.Notify(sigio, syscall.SIGIO)
+
+	_, err = fcntl(in, syscall.F_SETFL, syscall.O_ASYNC|syscall.O_NONBLOCK)
+	if err != nil {
+		return err
+	}
+	_, err = fcntl(in, syscall.F_SETOWN, syscall.Getpid())
+	if runtime.GOOS != "darwin" && err != nil {
+		return err
+	}
+	err = tcgetattr(out.Fd(), &orig_tios)
+	if err != nil {
+		return err
+	}
+
+	tios := orig_tios
+	tios.Iflag &^= syscall_IGNBRK | syscall_BRKINT | syscall_PARMRK |
+		syscall_ISTRIP | syscall_INLCR | syscall_IGNCR |
+		syscall_ICRNL | syscall_IXON
+	tios.Lflag &^= syscall_ECHO | syscall_ECHONL | syscall_ICANON |
+		syscall_ISIG | syscall_IEXTEN
+	tios.Cflag &^= syscall_CSIZE | syscall_PARENB
+	tios.Cflag |= syscall_CS8
+	tios.Cc[syscall_VMIN] = 1
+	tios.Cc[syscall_VTIME] = 0
+
+	err = tcsetattr(out.Fd(), &tios)
+	if err != nil {
+		return err
+	}
+
+	out.WriteString(funcs[t_enter_ca])
+	out.WriteString(funcs[t_enter_keypad])
+	out.WriteString(funcs[t_hide_cursor])
+	out.WriteString(funcs[t_clear_screen])
+
+	termw, termh = get_term_size(out.Fd())
+	back_buffer.init(termw, termh)
+	front_buffer.init(termw, termh)
+	back_buffer.clear()
+	front_buffer.clear()
+
+	go func() {
+		buf := make([]byte, 128)
+		for {
+			select {
+			case <-sigio:
+				for {
+					n, err := syscall.Read(in, buf)
+					if err == syscall.EAGAIN || err == syscall.EWOULDBLOCK {
+						break
+					}
+					select {
+					case input_comm <- input_event{buf[:n], err}:
+						ie := <-input_comm
+						buf = ie.data[:128]
+					case <-quit:
+						return
+					}
+				}
+			case <-quit:
+				return
+			}
+		}
+	}()
+
+	IsInit = true
+	return nil
+}
+
+// Interrupt an in-progress call to PollEvent by causing it to return
+// EventInterrupt.  Note that this function will block until the PollEvent
+// function has successfully been interrupted.
+func Interrupt() {
+	interrupt_comm <- struct{}{}
+}
+
+// Finalizes termbox library, should be called after successful initialization
+// when termbox's functionality isn't required anymore.
+func Close() {
+	quit <- 1
+	out.WriteString(funcs[t_show_cursor])
+	out.WriteString(funcs[t_sgr0])
+	out.WriteString(funcs[t_clear_screen])
+	out.WriteString(funcs[t_exit_ca])
+	out.WriteString(funcs[t_exit_keypad])
+	out.WriteString(funcs[t_exit_mouse])
+	tcsetattr(out.Fd(), &orig_tios)
+
+	out.Close()
+	syscall.Close(in)
+
+	// reset the state, so that on next Init() it will work again
+	termw = 0
+	termh = 0
+	input_mode = InputEsc
+	out = nil
+	in = 0
+	lastfg = attr_invalid
+	lastbg = attr_invalid
+	lastx = coord_invalid
+	lasty = coord_invalid
+	cursor_x = cursor_hidden
+	cursor_y = cursor_hidden
+	foreground = ColorDefault
+	background = ColorDefault
+	IsInit = false
+}
+
+// Synchronizes the internal back buffer with the terminal.
+func Flush() error {
+	// invalidate cursor position
+	lastx = coord_invalid
+	lasty = coord_invalid
+
+	update_size_maybe()
+
+	for y := 0; y < front_buffer.height; y++ {
+		line_offset := y * front_buffer.width
+		for x := 0; x < front_buffer.width; {
+			cell_offset := line_offset + x
+			back := &back_buffer.cells[cell_offset]
+			front := &front_buffer.cells[cell_offset]
+			if back.Ch < ' ' {
+				back.Ch = ' '
+			}
+			w := runewidth.RuneWidth(back.Ch)
+			if w == 0 || w == 2 && runewidth.IsAmbiguousWidth(back.Ch) {
+				w = 1
+			}
+			if *back == *front {
+				x += w
+				continue
+			}
+			*front = *back
+			send_attr(back.Fg, back.Bg)
+
+			if w == 2 && x == front_buffer.width-1 {
+				// there's not enough space for 2-cells rune,
+				// let's just put a space in there
+				send_char(x, y, ' ')
+			} else {
+				send_char(x, y, back.Ch)
+				if w == 2 {
+					next := cell_offset + 1
+					front_buffer.cells[next] = Cell{
+						Ch: 0,
+						Fg: back.Fg,
+						Bg: back.Bg,
+					}
+				}
+			}
+			x += w
+		}
+	}
+	if !is_cursor_hidden(cursor_x, cursor_y) {
+		write_cursor(cursor_x, cursor_y)
+	}
+	return flush()
+}
+
+// Sets the position of the cursor. See also HideCursor().
+func SetCursor(x, y int) {
+	if is_cursor_hidden(cursor_x, cursor_y) && !is_cursor_hidden(x, y) {
+		outbuf.WriteString(funcs[t_show_cursor])
+	}
+
+	if !is_cursor_hidden(cursor_x, cursor_y) && is_cursor_hidden(x, y) {
+		outbuf.WriteString(funcs[t_hide_cursor])
+	}
+
+	cursor_x, cursor_y = x, y
+	if !is_cursor_hidden(cursor_x, cursor_y) {
+		write_cursor(cursor_x, cursor_y)
+	}
+}
+
+// The shortcut for SetCursor(-1, -1).
+func HideCursor() {
+	SetCursor(cursor_hidden, cursor_hidden)
+}
+
+// Changes cell's parameters in the internal back buffer at the specified
+// position.
+func SetCell(x, y int, ch rune, fg, bg Attribute) {
+	if x < 0 || x >= back_buffer.width {
+		return
+	}
+	if y < 0 || y >= back_buffer.height {
+		return
+	}
+
+	back_buffer.cells[y*back_buffer.width+x] = Cell{ch, fg, bg}
+}
+
+// Returns a slice into the termbox's back buffer. You can get its dimensions
+// using 'Size' function. The slice remains valid as long as no 'Clear' or
+// 'Flush' function calls were made after call to this function.
+func CellBuffer() []Cell {
+	return back_buffer.cells
+}
+
+// After getting a raw event from PollRawEvent function call, you can parse it
+// again into an ordinary one using termbox logic. That is parse an event as
+// termbox would do it. Returned event in addition to usual Event struct fields
+// sets N field to the amount of bytes used within 'data' slice. If the length
+// of 'data' slice is zero or event cannot be parsed for some other reason, the
+// function will return a special event type: EventNone.
+//
+// IMPORTANT: EventNone may contain a non-zero N, which means you should skip
+// these bytes, because termbox cannot recognize them.
+//
+// NOTE: This API is experimental and may change in future.
+func ParseEvent(data []byte) Event {
+	event := Event{Type: EventKey}
+	ok := extract_event(data, &event)
+	if !ok {
+		return Event{Type: EventNone, N: event.N}
+	}
+	return event
+}
+
+// Wait for an event and return it. This is a blocking function call. Instead
+// of EventKey and EventMouse it returns EventRaw events. Raw event is written
+// into `data` slice and Event's N field is set to the amount of bytes written.
+// The minimum required length of the 'data' slice is 1. This requirement may
+// vary on different platforms.
+//
+// NOTE: This API is experimental and may change in future.
+func PollRawEvent(data []byte) Event {
+	if len(data) == 0 {
+		panic("len(data) >= 1 is a requirement")
+	}
+
+	var event Event
+	if extract_raw_event(data, &event) {
+		return event
+	}
+
+	for {
+		select {
+		case ev := <-input_comm:
+			if ev.err != nil {
+				return Event{Type: EventError, Err: ev.err}
+			}
+
+			inbuf = append(inbuf, ev.data...)
+			input_comm <- ev
+			if extract_raw_event(data, &event) {
+				return event
+			}
+		case <-interrupt_comm:
+			event.Type = EventInterrupt
+			return event
+
+		case <-sigwinch:
+			event.Type = EventResize
+			event.Width, event.Height = get_term_size(out.Fd())
+			return event
+		}
+	}
+}
+
+// Wait for an event and return it. This is a blocking function call.
+func PollEvent() Event {
+	var event Event
+
+	// try to extract event from input buffer, return on success
+	event.Type = EventKey
+	ok := extract_event(inbuf, &event)
+	if event.N != 0 {
+		copy(inbuf, inbuf[event.N:])
+		inbuf = inbuf[:len(inbuf)-event.N]
+	}
+	if ok {
+		return event
+	}
+
+	for {
+		select {
+		case ev := <-input_comm:
+			if ev.err != nil {
+				return Event{Type: EventError, Err: ev.err}
+			}
+
+			inbuf = append(inbuf, ev.data...)
+			input_comm <- ev
+			ok := extract_event(inbuf, &event)
+			if event.N != 0 {
+				copy(inbuf, inbuf[event.N:])
+				inbuf = inbuf[:len(inbuf)-event.N]
+			}
+			if ok {
+				return event
+			}
+		case <-interrupt_comm:
+			event.Type = EventInterrupt
+			return event
+
+		case <-sigwinch:
+			event.Type = EventResize
+			event.Width, event.Height = get_term_size(out.Fd())
+			return event
+		}
+	}
+}
+
+// Returns the size of the internal back buffer (which is mostly the same as
+// terminal's window size in characters). But it doesn't always match the size
+// of the terminal window, after the terminal size has changed, the internal
+// back buffer will get in sync only after Clear or Flush function calls.
+func Size() (width int, height int) {
+	return termw, termh
+}
+
+// Clears the internal back buffer.
+func Clear(fg, bg Attribute) error {
+	foreground, background = fg, bg
+	err := update_size_maybe()
+	back_buffer.clear()
+	return err
+}
+
+// Sets termbox input mode. Termbox has two input modes:
+//
+// 1. Esc input mode. When ESC sequence is in the buffer and it doesn't match
+// any known sequence. ESC means KeyEsc. This is the default input mode.
+//
+// 2. Alt input mode. When ESC sequence is in the buffer and it doesn't match
+// any known sequence. ESC enables ModAlt modifier for the next keyboard event.
+//
+// Both input modes can be OR'ed with Mouse mode. Setting Mouse mode bit up will
+// enable mouse button press/release and drag events.
+//
+// If 'mode' is InputCurrent, returns the current input mode. See also Input*
+// constants.
+func SetInputMode(mode InputMode) InputMode {
+	if mode == InputCurrent {
+		return input_mode
+	}
+	if mode&(InputEsc|InputAlt) == 0 {
+		mode |= InputEsc
+	}
+	if mode&(InputEsc|InputAlt) == InputEsc|InputAlt {
+		mode &^= InputAlt
+	}
+	if mode&InputMouse != 0 {
+		out.WriteString(funcs[t_enter_mouse])
+	} else {
+		out.WriteString(funcs[t_exit_mouse])
+	}
+
+	input_mode = mode
+	return input_mode
+}
+
+// Sets the termbox output mode. Termbox has four output options:
+//
+// 1. OutputNormal => [1..8]
+//    This mode provides 8 different colors:
+//        black, red, green, yellow, blue, magenta, cyan, white
+//    Shortcut: ColorBlack, ColorRed, ...
+//    Attributes: AttrBold, AttrUnderline, AttrReverse
+//
+//    Example usage:
+//        SetCell(x, y, '@', ColorBlack | AttrBold, ColorRed);
+//
+// 2. Output256 => [1..256]
+//    In this mode you can leverage the 256 terminal mode:
+//    0x01 - 0x08: the 8 colors as in OutputNormal
+//    0x09 - 0x10: Color* | AttrBold
+//    0x11 - 0xe8: 216 different colors
+//    0xe9 - 0x1ff: 24 different shades of grey
+//
+//    Example usage:
+//        SetCell(x, y, '@', 184, 240);
+//        SetCell(x, y, '@', 0xb8, 0xf0);
+//
+// 3. Output216 => [1..216]
+//    This mode supports the 3rd range of the 256 mode only.
+//    But you dont need to provide an offset.
+//
+// 4. OutputGrayscale => [1..26]
+//    This mode supports the 4th range of the 256 mode
+//    and black and white colors from 3th range of the 256 mode
+//    But you dont need to provide an offset.
+//
+// In all modes, 0x00 represents the default color.
+//
+// `go run _demos/output.go` to see its impact on your terminal.
+//
+// If 'mode' is OutputCurrent, it returns the current output mode.
+//
+// Note that this may return a different OutputMode than the one requested,
+// as the requested mode may not be available on the target platform.
+func SetOutputMode(mode OutputMode) OutputMode {
+	if mode == OutputCurrent {
+		return output_mode
+	}
+
+	output_mode = mode
+	return output_mode
+}
+
+// Sync comes handy when something causes desync between termbox's understanding
+// of a terminal buffer and the reality. Such as a third party process. Sync
+// forces a complete resync between the termbox and a terminal, it may not be
+// visually pretty though.
+func Sync() error {
+	front_buffer.clear()
+	err := send_clear()
+	if err != nil {
+		return err
+	}
+
+	return Flush()
+}