// +build !windows
package termbox
import "github.com/mattn/go-runewidth"
import "fmt"
import "os"
import "os/signal"
import "syscall"
import "runtime"
import "time"
// 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}
status := extract_event(data, &event, false)
if status != event_extracted {
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 {
// Constant governing macOS specific behavior. See https://github.com/nsf/termbox-go/issues/132
// This is an arbitrary delay which hopefully will be enough time for any lagging
// partial escape sequences to come through.
const esc_wait_delay = 100 * time.Millisecond
var event Event
var esc_wait_timer *time.Timer
var esc_timeout <-chan time.Time
// try to extract event from input buffer, return on success
event.Type = EventKey
status := extract_event(inbuf, &event, true)
if event.N != 0 {
copy(inbuf, inbuf[event.N:])
inbuf = inbuf[:len(inbuf)-event.N]
}
if status == event_extracted {
return event
} else if status == esc_wait {
esc_wait_timer = time.NewTimer(esc_wait_delay)
esc_timeout = esc_wait_timer.C
}
for {
select {
case ev := <-input_comm:
if esc_wait_timer != nil {
if !esc_wait_timer.Stop() {
<-esc_wait_timer.C
}
esc_wait_timer = nil
}
if ev.err != nil {
return Event{Type: EventError, Err: ev.err}
}
inbuf = append(inbuf, ev.data...)
input_comm <- ev
status := extract_event(inbuf, &event, true)
if event.N != 0 {
copy(inbuf, inbuf[event.N:])
inbuf = inbuf[:len(inbuf)-event.N]
}
if status == event_extracted {
return event
} else if status == esc_wait {
esc_wait_timer = time.NewTimer(esc_wait_delay)
esc_timeout = esc_wait_timer.C
}
case <-esc_timeout:
esc_wait_timer = nil
status := extract_event(inbuf, &event, false)
if event.N != 0 {
copy(inbuf, inbuf[event.N:])
inbuf = inbuf[:len(inbuf)-event.N]
}
if status == event_extracted {
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 don't 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 don't 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()
}
