aboutsummaryrefslogtreecommitdiffstats
path: root/vendor/github.com/nsf/termbox-go/termbox.go
blob: fbe4c3de9d2f80a1945c445d90c54873aa3d8f2b (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
// +build !windows

package termbox

import "unicode/utf8"
import "bytes"
import "syscall"
import "unsafe"
import "strings"
import "strconv"
import "os"
import "io"

// private API

const (
	t_enter_ca = iota
	t_exit_ca
	t_show_cursor
	t_hide_cursor
	t_clear_screen
	t_sgr0
	t_underline
	t_bold
	t_blink
	t_reverse
	t_enter_keypad
	t_exit_keypad
	t_enter_mouse
	t_exit_mouse
	t_max_funcs
)

const (
	coord_invalid = -2
	attr_invalid  = Attribute(0xFFFF)
)

type input_event struct {
	data []byte
	err  error
}

type extract_event_res int

const (
	event_not_extracted extract_event_res = iota
	event_extracted
	esc_wait
)

var (
	// term specific sequences
	keys  []string
	funcs []string

	// termbox inner state
	orig_tios      syscall_Termios
	back_buffer    cellbuf
	front_buffer   cellbuf
	termw          int
	termh          int
	input_mode     = InputEsc
	output_mode    = OutputNormal
	out            *os.File
	in             int
	lastfg         = attr_invalid
	lastbg         = attr_invalid
	lastx          = coord_invalid
	lasty          = coord_invalid
	cursor_x       = cursor_hidden
	cursor_y       = cursor_hidden
	foreground     = ColorDefault
	background     = ColorDefault
	inbuf          = make([]byte, 0, 64)
	outbuf         bytes.Buffer
	sigwinch       = make(chan os.Signal, 1)
	sigio          = make(chan os.Signal, 1)
	quit           = make(chan int)
	input_comm     = make(chan input_event)
	interrupt_comm = make(chan struct{})
	intbuf         = make([]byte, 0, 16)

	// grayscale indexes
	grayscale = []Attribute{
		0, 17, 233, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244,
		245, 246, 247, 248, 249, 250, 251, 252, 253, 254, 255, 256, 232,
	}
)

func write_cursor(x, y int) {
	outbuf.WriteString("\033[")
	outbuf.Write(strconv.AppendUint(intbuf, uint64(y+1), 10))
	outbuf.WriteString(";")
	outbuf.Write(strconv.AppendUint(intbuf, uint64(x+1), 10))
	outbuf.WriteString("H")
}

func write_sgr_fg(a Attribute) {
	switch output_mode {
	case Output256, Output216, OutputGrayscale:
		outbuf.WriteString("\033[38;5;")
		outbuf.Write(strconv.AppendUint(intbuf, uint64(a-1), 10))
		outbuf.WriteString("m")
	default:
		outbuf.WriteString("\033[3")
		outbuf.Write(strconv.AppendUint(intbuf, uint64(a-1), 10))
		outbuf.WriteString("m")
	}
}

func write_sgr_bg(a Attribute) {
	switch output_mode {
	case Output256, Output216, OutputGrayscale:
		outbuf.WriteString("\033[48;5;")
		outbuf.Write(strconv.AppendUint(intbuf, uint64(a-1), 10))
		outbuf.WriteString("m")
	default:
		outbuf.WriteString("\033[4")
		outbuf.Write(strconv.AppendUint(intbuf, uint64(a-1), 10))
		outbuf.WriteString("m")
	}
}

func write_sgr(fg, bg Attribute) {
	switch output_mode {
	case Output256, Output216, OutputGrayscale:
		outbuf.WriteString("\033[38;5;")
		outbuf.Write(strconv.AppendUint(intbuf, uint64(fg-1), 10))
		outbuf.WriteString("m")
		outbuf.WriteString("\033[48;5;")
		outbuf.Write(strconv.AppendUint(intbuf, uint64(bg-1), 10))
		outbuf.WriteString("m")
	default:
		outbuf.WriteString("\033[3")
		outbuf.Write(strconv.AppendUint(intbuf, uint64(fg-1), 10))
		outbuf.WriteString(";4")
		outbuf.Write(strconv.AppendUint(intbuf, uint64(bg-1), 10))
		outbuf.WriteString("m")
	}
}

type winsize struct {
	rows    uint16
	cols    uint16
	xpixels uint16
	ypixels uint16
}

func get_term_size(fd uintptr) (int, int) {
	var sz winsize
	_, _, _ = syscall.Syscall(syscall.SYS_IOCTL,
		fd, uintptr(syscall.TIOCGWINSZ), uintptr(unsafe.Pointer(&sz)))
	return int(sz.cols), int(sz.rows)
}

func send_attr(fg, bg Attribute) {
	if fg == lastfg && bg == lastbg {
		return
	}

	outbuf.WriteString(funcs[t_sgr0])

	var fgcol, bgcol Attribute

	switch output_mode {
	case Output256:
		fgcol = fg & 0x1FF
		bgcol = bg & 0x1FF
	case Output216:
		fgcol = fg & 0xFF
		bgcol = bg & 0xFF
		if fgcol > 216 {
			fgcol = ColorDefault
		}
		if bgcol > 216 {
			bgcol = ColorDefault
		}
		if fgcol != ColorDefault {
			fgcol += 0x10
		}
		if bgcol != ColorDefault {
			bgcol += 0x10
		}
	case OutputGrayscale:
		fgcol = fg & 0x1F
		bgcol = bg & 0x1F
		if fgcol > 26 {
			fgcol = ColorDefault
		}
		if bgcol > 26 {
			bgcol = ColorDefault
		}
		if fgcol != ColorDefault {
			fgcol = grayscale[fgcol]
		}
		if bgcol != ColorDefault {
			bgcol = grayscale[bgcol]
		}
	default:
		fgcol = fg & 0x0F
		bgcol = bg & 0x0F
	}

	if fgcol != ColorDefault {
		if bgcol != ColorDefault {
			write_sgr(fgcol, bgcol)
		} else {
			write_sgr_fg(fgcol)
		}
	} else if bgcol != ColorDefault {
		write_sgr_bg(bgcol)
	}

	if fg&AttrBold != 0 {
		outbuf.WriteString(funcs[t_bold])
	}
	if bg&AttrBold != 0 {
		outbuf.WriteString(funcs[t_blink])
	}
	if fg&AttrUnderline != 0 {
		outbuf.WriteString(funcs[t_underline])
	}
	if fg&AttrReverse|bg&AttrReverse != 0 {
		outbuf.WriteString(funcs[t_reverse])
	}

	lastfg, lastbg = fg, bg
}

func send_char(x, y int, ch rune) {
	var buf [8]byte
	n := utf8.EncodeRune(buf[:], ch)
	if x-1 != lastx || y != lasty {
		write_cursor(x, y)
	}
	lastx, lasty = x, y
	outbuf.Write(buf[:n])
}

func flush() error {
	_, err := io.Copy(out, &outbuf)
	outbuf.Reset()
	return err
}

func send_clear() error {
	send_attr(foreground, background)
	outbuf.WriteString(funcs[t_clear_screen])
	if !is_cursor_hidden(cursor_x, cursor_y) {
		write_cursor(cursor_x, cursor_y)
	}

	// we need to invalidate cursor position too and these two vars are
	// used only for simple cursor positioning optimization, cursor
	// actually may be in the correct place, but we simply discard
	// optimization once and it gives us simple solution for the case when
	// cursor moved
	lastx = coord_invalid
	lasty = coord_invalid

	return flush()
}

func update_size_maybe() error {
	w, h := get_term_size(out.Fd())
	if w != termw || h != termh {
		termw, termh = w, h
		back_buffer.resize(termw, termh)
		front_buffer.resize(termw, termh)
		front_buffer.clear()
		return send_clear()
	}
	return nil
}

func tcsetattr(fd uintptr, termios *syscall_Termios) error {
	r, _, e := syscall.Syscall(syscall.SYS_IOCTL,
		fd, uintptr(syscall_TCSETS), uintptr(unsafe.Pointer(termios)))
	if r != 0 {
		return os.NewSyscallError("SYS_IOCTL", e)
	}
	return nil
}

func tcgetattr(fd uintptr, termios *syscall_Termios) error {
	r, _, e := syscall.Syscall(syscall.SYS_IOCTL,
		fd, uintptr(syscall_TCGETS), uintptr(unsafe.Pointer(termios)))
	if r != 0 {
		return os.NewSyscallError("SYS_IOCTL", e)
	}
	return nil
}

func parse_mouse_event(event *Event, buf string) (int, bool) {
	if strings.HasPrefix(buf, "\033[M") && len(buf) >= 6 {
		// X10 mouse encoding, the simplest one
		// \033 [ M Cb Cx Cy
		b := buf[3] - 32
		switch b & 3 {
		case 0:
			if b&64 != 0 {
				event.Key = MouseWheelUp
			} else {
				event.Key = MouseLeft
			}
		case 1:
			if b&64 != 0 {
				event.Key = MouseWheelDown
			} else {
				event.Key = MouseMiddle
			}
		case 2:
			event.Key = MouseRight
		case 3:
			event.Key = MouseRelease
		default:
			return 6, false
		}
		event.Type = EventMouse // KeyEvent by default
		if b&32 != 0 {
			event.Mod |= ModMotion
		}

		// the coord is 1,1 for upper left
		event.MouseX = int(buf[4]) - 1 - 32
		event.MouseY = int(buf[5]) - 1 - 32
		return 6, true
	} else if strings.HasPrefix(buf, "\033[<") || strings.HasPrefix(buf, "\033[") {
		// xterm 1006 extended mode or urxvt 1015 extended mode
		// xterm: \033 [ < Cb ; Cx ; Cy (M or m)
		// urxvt: \033 [ Cb ; Cx ; Cy M

		// find the first M or m, that's where we stop
		mi := strings.IndexAny(buf, "Mm")
		if mi == -1 {
			return 0, false
		}

		// whether it's a capital M or not
		isM := buf[mi] == 'M'

		// whether it's urxvt or not
		isU := false

		// buf[2] is safe here, because having M or m found means we have at
		// least 3 bytes in a string
		if buf[2] == '<' {
			buf = buf[3:mi]
		} else {
			isU = true
			buf = buf[2:mi]
		}

		s1 := strings.Index(buf, ";")
		s2 := strings.LastIndex(buf, ";")
		// not found or only one ';'
		if s1 == -1 || s2 == -1 || s1 == s2 {
			return 0, false
		}

		n1, err := strconv.ParseInt(buf[0:s1], 10, 64)
		if err != nil {
			return 0, false
		}
		n2, err := strconv.ParseInt(buf[s1+1:s2], 10, 64)
		if err != nil {
			return 0, false
		}
		n3, err := strconv.ParseInt(buf[s2+1:], 10, 64)
		if err != nil {
			return 0, false
		}

		// on urxvt, first number is encoded exactly as in X10, but we need to
		// make it zero-based, on xterm it is zero-based already
		if isU {
			n1 -= 32
		}
		switch n1 & 3 {
		case 0:
			if n1&64 != 0 {
				event.Key = MouseWheelUp
			} else {
				event.Key = MouseLeft
			}
		case 1:
			if n1&64 != 0 {
				event.Key = MouseWheelDown
			} else {
				event.Key = MouseMiddle
			}
		case 2:
			event.Key = MouseRight
		case 3:
			event.Key = MouseRelease
		default:
			return mi + 1, false
		}
		if !isM {
			// on xterm mouse release is signaled by lowercase m
			event.Key = MouseRelease
		}

		event.Type = EventMouse // KeyEvent by default
		if n1&32 != 0 {
			event.Mod |= ModMotion
		}

		event.MouseX = int(n2) - 1
		event.MouseY = int(n3) - 1
		return mi + 1, true
	}

	return 0, false
}

func parse_escape_sequence(event *Event, buf []byte) (int, bool) {
	bufstr := string(buf)
	for i, key := range keys {
		if strings.HasPrefix(bufstr, key) {
			event.Ch = 0
			event.Key = Key(0xFFFF - i)
			return len(key), true
		}
	}

	// if none of the keys match, let's try mouse sequences
	return parse_mouse_event(event, bufstr)
}

func extract_raw_event(data []byte, event *Event) bool {
	if len(inbuf) == 0 {
		return false
	}

	n := len(data)
	if n == 0 {
		return false
	}

	n = copy(data, inbuf)
	copy(inbuf, inbuf[n:])
	inbuf = inbuf[:len(inbuf)-n]

	event.N = n
	event.Type = EventRaw
	return true
}

func extract_event(inbuf []byte, event *Event, allow_esc_wait bool) extract_event_res {
	if len(inbuf) == 0 {
		event.N = 0
		return event_not_extracted
	}

	if inbuf[0] == '\033' {
		// possible escape sequence
		if n, ok := parse_escape_sequence(event, inbuf); n != 0 {
			event.N = n
			if ok {
				return event_extracted
			} else {
				return event_not_extracted
			}
		}

		// possible partially read escape sequence; trigger a wait if appropriate
		if enable_wait_for_escape_sequence() && allow_esc_wait {
			event.N = 0
			return esc_wait
		}

		// it's not escape sequence, then it's Alt or Esc, check input_mode
		switch {
		case input_mode&InputEsc != 0:
			// if we're in escape mode, fill Esc event, pop buffer, return success
			event.Ch = 0
			event.Key = KeyEsc
			event.Mod = 0
			event.N = 1
			return event_extracted
		case input_mode&InputAlt != 0:
			// if we're in alt mode, set Alt modifier to event and redo parsing
			event.Mod = ModAlt
			status := extract_event(inbuf[1:], event, false)
			if status == event_extracted {
				event.N++
			} else {
				event.N = 0
			}
			return status
		default:
			panic("unreachable")
		}
	}

	// if we're here, this is not an escape sequence and not an alt sequence
	// so, it's a FUNCTIONAL KEY or a UNICODE character

	// first of all check if it's a functional key
	if Key(inbuf[0]) <= KeySpace || Key(inbuf[0]) == KeyBackspace2 {
		// fill event, pop buffer, return success
		event.Ch = 0
		event.Key = Key(inbuf[0])
		event.N = 1
		return event_extracted
	}

	// the only possible option is utf8 rune
	if r, n := utf8.DecodeRune(inbuf); r != utf8.RuneError {
		event.Ch = r
		event.Key = 0
		event.N = n
		return event_extracted
	}

	return event_not_extracted
}

func fcntl(fd int, cmd int, arg int) (val int, err error) {
	r, _, e := syscall.Syscall(syscall.SYS_FCNTL, uintptr(fd), uintptr(cmd),
		uintptr(arg))
	val = int(r)
	if e != 0 {
		err = e
	}
	return
}