xref: /openbsd-src/usr.bin/tmux/tty.c (revision 58fbf5d6aa35e3d66f2c32c61d2f38824a990e85)
1 /* $OpenBSD: tty.c,v 1.389 2021/02/17 07:18:36 nicm Exp $ */
2 
3 /*
4  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
15  * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
16  * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <sys/types.h>
20 #include <sys/ioctl.h>
21 
22 #include <netinet/in.h>
23 
24 #include <curses.h>
25 #include <errno.h>
26 #include <fcntl.h>
27 #include <resolv.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <termios.h>
31 #include <unistd.h>
32 
33 #include "tmux.h"
34 
35 static int	tty_log_fd = -1;
36 
37 static int	tty_client_ready(struct client *);
38 
39 static void	tty_set_italics(struct tty *);
40 static int	tty_try_colour(struct tty *, int, const char *);
41 static void	tty_force_cursor_colour(struct tty *, const char *);
42 static void	tty_cursor_pane(struct tty *, const struct tty_ctx *, u_int,
43 		    u_int);
44 static void	tty_cursor_pane_unless_wrap(struct tty *,
45 		    const struct tty_ctx *, u_int, u_int);
46 static void	tty_invalidate(struct tty *);
47 static void	tty_colours(struct tty *, const struct grid_cell *);
48 static void	tty_check_fg(struct tty *, int *, struct grid_cell *);
49 static void	tty_check_bg(struct tty *, int *, struct grid_cell *);
50 static void	tty_check_us(struct tty *, int *, struct grid_cell *);
51 static void	tty_colours_fg(struct tty *, const struct grid_cell *);
52 static void	tty_colours_bg(struct tty *, const struct grid_cell *);
53 static void	tty_colours_us(struct tty *, const struct grid_cell *);
54 
55 static void	tty_region_pane(struct tty *, const struct tty_ctx *, u_int,
56 		    u_int);
57 static void	tty_region(struct tty *, u_int, u_int);
58 static void	tty_margin_pane(struct tty *, const struct tty_ctx *);
59 static void	tty_margin(struct tty *, u_int, u_int);
60 static int	tty_large_region(struct tty *, const struct tty_ctx *);
61 static int	tty_fake_bce(const struct tty *, const struct grid_cell *,
62 		    u_int);
63 static void	tty_redraw_region(struct tty *, const struct tty_ctx *);
64 static void	tty_emulate_repeat(struct tty *, enum tty_code_code,
65 		    enum tty_code_code, u_int);
66 static void	tty_repeat_space(struct tty *, u_int);
67 static void	tty_draw_pane(struct tty *, const struct tty_ctx *, u_int);
68 static void	tty_default_attributes(struct tty *, const struct grid_cell *,
69 		    int *, u_int);
70 
71 #define tty_use_margin(tty) \
72 	(tty->term->flags & TERM_DECSLRM)
73 #define tty_full_width(tty, ctx) \
74 	((ctx)->xoff == 0 && (ctx)->sx >= (tty)->sx)
75 
76 #define TTY_BLOCK_INTERVAL (100000 /* 100 milliseconds */)
77 #define TTY_BLOCK_START(tty) (1 + ((tty)->sx * (tty)->sy) * 8)
78 #define TTY_BLOCK_STOP(tty) (1 + ((tty)->sx * (tty)->sy) / 8)
79 
80 void
81 tty_create_log(void)
82 {
83 	char	name[64];
84 
85 	xsnprintf(name, sizeof name, "tmux-out-%ld.log", (long)getpid());
86 
87 	tty_log_fd = open(name, O_WRONLY|O_CREAT|O_TRUNC, 0644);
88 	if (tty_log_fd != -1 && fcntl(tty_log_fd, F_SETFD, FD_CLOEXEC) == -1)
89 		fatal("fcntl failed");
90 }
91 
92 int
93 tty_init(struct tty *tty, struct client *c)
94 {
95 	if (!isatty(c->fd))
96 		return (-1);
97 
98 	memset(tty, 0, sizeof *tty);
99 	tty->client = c;
100 
101 	tty->cstyle = 0;
102 	tty->ccolour = xstrdup("");
103 
104 	if (tcgetattr(c->fd, &tty->tio) != 0)
105 		return (-1);
106 	return (0);
107 }
108 
109 void
110 tty_resize(struct tty *tty)
111 {
112 	struct client	*c = tty->client;
113 	struct winsize	 ws;
114 	u_int		 sx, sy, xpixel, ypixel;
115 
116 	if (ioctl(c->fd, TIOCGWINSZ, &ws) != -1) {
117 		sx = ws.ws_col;
118 		if (sx == 0) {
119 			sx = 80;
120 			xpixel = 0;
121 		} else
122 			xpixel = ws.ws_xpixel / sx;
123 		sy = ws.ws_row;
124 		if (sy == 0) {
125 			sy = 24;
126 			ypixel = 0;
127 		} else
128 			ypixel = ws.ws_ypixel / sy;
129 	} else {
130 		sx = 80;
131 		sy = 24;
132 		xpixel = 0;
133 		ypixel = 0;
134 	}
135 	log_debug("%s: %s now %ux%u (%ux%u)", __func__, c->name, sx, sy,
136 	    xpixel, ypixel);
137 	tty_set_size(tty, sx, sy, xpixel, ypixel);
138 	tty_invalidate(tty);
139 }
140 
141 void
142 tty_set_size(struct tty *tty, u_int sx, u_int sy, u_int xpixel, u_int ypixel)
143 {
144 	tty->sx = sx;
145 	tty->sy = sy;
146 	tty->xpixel = xpixel;
147 	tty->ypixel = ypixel;
148 }
149 
150 static void
151 tty_read_callback(__unused int fd, __unused short events, void *data)
152 {
153 	struct tty	*tty = data;
154 	struct client	*c = tty->client;
155 	const char	*name = c->name;
156 	size_t		 size = EVBUFFER_LENGTH(tty->in);
157 	int		 nread;
158 
159 	nread = evbuffer_read(tty->in, c->fd, -1);
160 	if (nread == 0 || nread == -1) {
161 		if (nread == 0)
162 			log_debug("%s: read closed", name);
163 		else
164 			log_debug("%s: read error: %s", name, strerror(errno));
165 		event_del(&tty->event_in);
166 		server_client_lost(tty->client);
167 		return;
168 	}
169 	log_debug("%s: read %d bytes (already %zu)", name, nread, size);
170 
171 	while (tty_keys_next(tty))
172 		;
173 }
174 
175 static void
176 tty_timer_callback(__unused int fd, __unused short events, void *data)
177 {
178 	struct tty	*tty = data;
179 	struct client	*c = tty->client;
180 	struct timeval	 tv = { .tv_usec = TTY_BLOCK_INTERVAL };
181 
182 	log_debug("%s: %zu discarded", c->name, tty->discarded);
183 
184 	c->flags |= CLIENT_ALLREDRAWFLAGS;
185 	c->discarded += tty->discarded;
186 
187 	if (tty->discarded < TTY_BLOCK_STOP(tty)) {
188 		tty->flags &= ~TTY_BLOCK;
189 		tty_invalidate(tty);
190 		return;
191 	}
192 	tty->discarded = 0;
193 	evtimer_add(&tty->timer, &tv);
194 }
195 
196 static int
197 tty_block_maybe(struct tty *tty)
198 {
199 	struct client	*c = tty->client;
200 	size_t		 size = EVBUFFER_LENGTH(tty->out);
201 	struct timeval	 tv = { .tv_usec = TTY_BLOCK_INTERVAL };
202 
203 	if (size < TTY_BLOCK_START(tty))
204 		return (0);
205 
206 	if (tty->flags & TTY_BLOCK)
207 		return (1);
208 	tty->flags |= TTY_BLOCK;
209 
210 	log_debug("%s: can't keep up, %zu discarded", c->name, size);
211 
212 	evbuffer_drain(tty->out, size);
213 	c->discarded += size;
214 
215 	tty->discarded = 0;
216 	evtimer_add(&tty->timer, &tv);
217 	return (1);
218 }
219 
220 static void
221 tty_write_callback(__unused int fd, __unused short events, void *data)
222 {
223 	struct tty	*tty = data;
224 	struct client	*c = tty->client;
225 	size_t		 size = EVBUFFER_LENGTH(tty->out);
226 	int		 nwrite;
227 
228 	nwrite = evbuffer_write(tty->out, c->fd);
229 	if (nwrite == -1)
230 		return;
231 	log_debug("%s: wrote %d bytes (of %zu)", c->name, nwrite, size);
232 
233 	if (c->redraw > 0) {
234 		if ((size_t)nwrite >= c->redraw)
235 			c->redraw = 0;
236 		else
237 			c->redraw -= nwrite;
238 		log_debug("%s: waiting for redraw, %zu bytes left", c->name,
239 		    c->redraw);
240 	} else if (tty_block_maybe(tty))
241 		return;
242 
243 	if (EVBUFFER_LENGTH(tty->out) != 0)
244 		event_add(&tty->event_out, NULL);
245 }
246 
247 int
248 tty_open(struct tty *tty, char **cause)
249 {
250 	struct client	*c = tty->client;
251 
252 	tty->term = tty_term_create(tty, c->term_name, c->term_caps,
253 	    c->term_ncaps, &c->term_features, cause);
254 	if (tty->term == NULL) {
255 		tty_close(tty);
256 		return (-1);
257 	}
258 	tty->flags |= TTY_OPENED;
259 
260 	tty->flags &= ~(TTY_NOCURSOR|TTY_FREEZE|TTY_BLOCK|TTY_TIMER);
261 
262 	event_set(&tty->event_in, c->fd, EV_PERSIST|EV_READ,
263 	    tty_read_callback, tty);
264 	tty->in = evbuffer_new();
265 	if (tty->in == NULL)
266 		fatal("out of memory");
267 
268 	event_set(&tty->event_out, c->fd, EV_WRITE, tty_write_callback, tty);
269 	tty->out = evbuffer_new();
270 	if (tty->out == NULL)
271 		fatal("out of memory");
272 
273 	evtimer_set(&tty->timer, tty_timer_callback, tty);
274 
275 	tty_start_tty(tty);
276 
277 	tty_keys_build(tty);
278 
279 	return (0);
280 }
281 
282 static void
283 tty_start_timer_callback(__unused int fd, __unused short events, void *data)
284 {
285 	struct tty	*tty = data;
286 	struct client	*c = tty->client;
287 
288 	log_debug("%s: start timer fired", c->name);
289 	if ((tty->flags & (TTY_HAVEDA|TTY_HAVEXDA)) == 0)
290 		tty_update_features(tty);
291 	tty->flags |= (TTY_HAVEDA|TTY_HAVEXDA);
292 }
293 
294 void
295 tty_start_tty(struct tty *tty)
296 {
297 	struct client	*c = tty->client;
298 	struct termios	 tio;
299 	struct timeval	 tv = { .tv_sec = 1 };
300 
301 	setblocking(c->fd, 0);
302 	event_add(&tty->event_in, NULL);
303 
304 	memcpy(&tio, &tty->tio, sizeof tio);
305 	tio.c_iflag &= ~(IXON|IXOFF|ICRNL|INLCR|IGNCR|IMAXBEL|ISTRIP);
306 	tio.c_iflag |= IGNBRK;
307 	tio.c_oflag &= ~(OPOST|ONLCR|OCRNL|ONLRET);
308 	tio.c_lflag &= ~(IEXTEN|ICANON|ECHO|ECHOE|ECHONL|ECHOCTL|ECHOPRT|
309 	    ECHOKE|ISIG);
310 	tio.c_cc[VMIN] = 1;
311 	tio.c_cc[VTIME] = 0;
312 	if (tcsetattr(c->fd, TCSANOW, &tio) == 0)
313 		tcflush(c->fd, TCIOFLUSH);
314 
315 	tty_putcode(tty, TTYC_SMCUP);
316 
317 	tty_putcode(tty, TTYC_SMKX);
318 	tty_putcode(tty, TTYC_CLEAR);
319 
320 	if (tty_acs_needed(tty)) {
321 		log_debug("%s: using capabilities for ACS", c->name);
322 		tty_putcode(tty, TTYC_ENACS);
323 	} else
324 		log_debug("%s: using UTF-8 for ACS", c->name);
325 
326 	tty_putcode(tty, TTYC_CNORM);
327 	if (tty_term_has(tty->term, TTYC_KMOUS)) {
328 		tty_puts(tty, "\033[?1000l\033[?1002l\033[?1003l");
329 		tty_puts(tty, "\033[?1006l\033[?1005l");
330 	}
331 
332 	evtimer_set(&tty->start_timer, tty_start_timer_callback, tty);
333 	evtimer_add(&tty->start_timer, &tv);
334 
335 	tty->flags |= TTY_STARTED;
336 	tty_invalidate(tty);
337 
338 	if (*tty->ccolour != '\0')
339 		tty_force_cursor_colour(tty, "");
340 
341 	tty->mouse_drag_flag = 0;
342 	tty->mouse_drag_update = NULL;
343 	tty->mouse_drag_release = NULL;
344 }
345 
346 void
347 tty_send_requests(struct tty *tty)
348 {
349 	if (~tty->flags & TTY_STARTED)
350 		return;
351 
352 	if (tty->term->flags & TERM_VT100LIKE) {
353 		if (~tty->flags & TTY_HAVEDA)
354 			tty_puts(tty, "\033[>c");
355 		if (~tty->flags & TTY_HAVEXDA)
356 			tty_puts(tty, "\033[>q");
357 	} else
358 		tty->flags |= (TTY_HAVEDA|TTY_HAVEXDA);
359 }
360 
361 void
362 tty_stop_tty(struct tty *tty)
363 {
364 	struct client	*c = tty->client;
365 	struct winsize	 ws;
366 
367 	if (!(tty->flags & TTY_STARTED))
368 		return;
369 	tty->flags &= ~TTY_STARTED;
370 
371 	evtimer_del(&tty->start_timer);
372 
373 	event_del(&tty->timer);
374 	tty->flags &= ~TTY_BLOCK;
375 
376 	event_del(&tty->event_in);
377 	event_del(&tty->event_out);
378 
379 	/*
380 	 * Be flexible about error handling and try not kill the server just
381 	 * because the fd is invalid. Things like ssh -t can easily leave us
382 	 * with a dead tty.
383 	 */
384 	if (ioctl(c->fd, TIOCGWINSZ, &ws) == -1)
385 		return;
386 	if (tcsetattr(c->fd, TCSANOW, &tty->tio) == -1)
387 		return;
388 
389 	tty_raw(tty, tty_term_string2(tty->term, TTYC_CSR, 0, ws.ws_row - 1));
390 	if (tty_acs_needed(tty))
391 		tty_raw(tty, tty_term_string(tty->term, TTYC_RMACS));
392 	tty_raw(tty, tty_term_string(tty->term, TTYC_SGR0));
393 	tty_raw(tty, tty_term_string(tty->term, TTYC_RMKX));
394 	tty_raw(tty, tty_term_string(tty->term, TTYC_CLEAR));
395 	if (tty_term_has(tty->term, TTYC_SS) && tty->cstyle != 0) {
396 		if (tty_term_has(tty->term, TTYC_SE))
397 			tty_raw(tty, tty_term_string(tty->term, TTYC_SE));
398 		else
399 			tty_raw(tty, tty_term_string1(tty->term, TTYC_SS, 0));
400 	}
401 	if (tty->mode & MODE_BRACKETPASTE)
402 		tty_raw(tty, tty_term_string(tty->term, TTYC_DSBP));
403 	if (*tty->ccolour != '\0')
404 		tty_raw(tty, tty_term_string(tty->term, TTYC_CR));
405 
406 	tty_raw(tty, tty_term_string(tty->term, TTYC_CNORM));
407 	if (tty_term_has(tty->term, TTYC_KMOUS)) {
408 		tty_raw(tty, "\033[?1000l\033[?1002l\033[?1003l");
409 		tty_raw(tty, "\033[?1006l\033[?1005l");
410 	}
411 
412 	if (tty->term->flags & TERM_VT100LIKE)
413 		tty_raw(tty, "\033[?7727l");
414 	tty_raw(tty, tty_term_string(tty->term, TTYC_DSFCS));
415 	tty_raw(tty, tty_term_string(tty->term, TTYC_DSEKS));
416 
417 	if (tty_use_margin(tty))
418 		tty_raw(tty, tty_term_string(tty->term, TTYC_DSMG));
419 	tty_raw(tty, tty_term_string(tty->term, TTYC_RMCUP));
420 
421 	setblocking(c->fd, 1);
422 }
423 
424 void
425 tty_close(struct tty *tty)
426 {
427 	if (event_initialized(&tty->key_timer))
428 		evtimer_del(&tty->key_timer);
429 	tty_stop_tty(tty);
430 
431 	if (tty->flags & TTY_OPENED) {
432 		evbuffer_free(tty->in);
433 		event_del(&tty->event_in);
434 		evbuffer_free(tty->out);
435 		event_del(&tty->event_out);
436 
437 		tty_term_free(tty->term);
438 		tty_keys_free(tty);
439 
440 		tty->flags &= ~TTY_OPENED;
441 	}
442 }
443 
444 void
445 tty_free(struct tty *tty)
446 {
447 	tty_close(tty);
448 	free(tty->ccolour);
449 }
450 
451 void
452 tty_update_features(struct tty *tty)
453 {
454 	struct client	*c = tty->client;
455 
456 	if (tty_apply_features(tty->term, c->term_features))
457 		tty_term_apply_overrides(tty->term);
458 
459 	if (tty_use_margin(tty))
460 		tty_putcode(tty, TTYC_ENMG);
461 	if (options_get_number(global_options, "extended-keys"))
462 		tty_puts(tty, tty_term_string(tty->term, TTYC_ENEKS));
463 	if (options_get_number(global_options, "focus-events"))
464 		tty_puts(tty, tty_term_string(tty->term, TTYC_ENFCS));
465 	if (tty->term->flags & TERM_VT100LIKE)
466 		tty_puts(tty, "\033[?7727h");
467 }
468 
469 void
470 tty_raw(struct tty *tty, const char *s)
471 {
472 	struct client	*c = tty->client;
473 	ssize_t		 n, slen;
474 	u_int		 i;
475 
476 	slen = strlen(s);
477 	for (i = 0; i < 5; i++) {
478 		n = write(c->fd, s, slen);
479 		if (n >= 0) {
480 			s += n;
481 			slen -= n;
482 			if (slen == 0)
483 				break;
484 		} else if (n == -1 && errno != EAGAIN)
485 			break;
486 		usleep(100);
487 	}
488 }
489 
490 void
491 tty_putcode(struct tty *tty, enum tty_code_code code)
492 {
493 	tty_puts(tty, tty_term_string(tty->term, code));
494 }
495 
496 void
497 tty_putcode1(struct tty *tty, enum tty_code_code code, int a)
498 {
499 	if (a < 0)
500 		return;
501 	tty_puts(tty, tty_term_string1(tty->term, code, a));
502 }
503 
504 void
505 tty_putcode2(struct tty *tty, enum tty_code_code code, int a, int b)
506 {
507 	if (a < 0 || b < 0)
508 		return;
509 	tty_puts(tty, tty_term_string2(tty->term, code, a, b));
510 }
511 
512 void
513 tty_putcode3(struct tty *tty, enum tty_code_code code, int a, int b, int c)
514 {
515 	if (a < 0 || b < 0 || c < 0)
516 		return;
517 	tty_puts(tty, tty_term_string3(tty->term, code, a, b, c));
518 }
519 
520 void
521 tty_putcode_ptr1(struct tty *tty, enum tty_code_code code, const void *a)
522 {
523 	if (a != NULL)
524 		tty_puts(tty, tty_term_ptr1(tty->term, code, a));
525 }
526 
527 void
528 tty_putcode_ptr2(struct tty *tty, enum tty_code_code code, const void *a,
529     const void *b)
530 {
531 	if (a != NULL && b != NULL)
532 		tty_puts(tty, tty_term_ptr2(tty->term, code, a, b));
533 }
534 
535 static void
536 tty_add(struct tty *tty, const char *buf, size_t len)
537 {
538 	struct client	*c = tty->client;
539 
540 	if (tty->flags & TTY_BLOCK) {
541 		tty->discarded += len;
542 		return;
543 	}
544 
545 	evbuffer_add(tty->out, buf, len);
546 	log_debug("%s: %.*s", c->name, (int)len, buf);
547 	c->written += len;
548 
549 	if (tty_log_fd != -1)
550 		write(tty_log_fd, buf, len);
551 	if (tty->flags & TTY_STARTED)
552 		event_add(&tty->event_out, NULL);
553 }
554 
555 void
556 tty_puts(struct tty *tty, const char *s)
557 {
558 	if (*s != '\0')
559 		tty_add(tty, s, strlen(s));
560 }
561 
562 void
563 tty_putc(struct tty *tty, u_char ch)
564 {
565 	const char	*acs;
566 
567 	if ((tty->term->flags & TERM_NOAM) &&
568 	    ch >= 0x20 && ch != 0x7f &&
569 	    tty->cy == tty->sy - 1 &&
570 	    tty->cx + 1 >= tty->sx)
571 		return;
572 
573 	if (tty->cell.attr & GRID_ATTR_CHARSET) {
574 		acs = tty_acs_get(tty, ch);
575 		if (acs != NULL)
576 			tty_add(tty, acs, strlen(acs));
577 		else
578 			tty_add(tty, &ch, 1);
579 	} else
580 		tty_add(tty, &ch, 1);
581 
582 	if (ch >= 0x20 && ch != 0x7f) {
583 		if (tty->cx >= tty->sx) {
584 			tty->cx = 1;
585 			if (tty->cy != tty->rlower)
586 				tty->cy++;
587 
588 			/*
589 			 * On !am terminals, force the cursor position to where
590 			 * we think it should be after a line wrap - this means
591 			 * it works on sensible terminals as well.
592 			 */
593 			if (tty->term->flags & TERM_NOAM)
594 				tty_putcode2(tty, TTYC_CUP, tty->cy, tty->cx);
595 		} else
596 			tty->cx++;
597 	}
598 }
599 
600 void
601 tty_putn(struct tty *tty, const void *buf, size_t len, u_int width)
602 {
603 	if ((tty->term->flags & TERM_NOAM) &&
604 	    tty->cy == tty->sy - 1 &&
605 	    tty->cx + len >= tty->sx)
606 		len = tty->sx - tty->cx - 1;
607 
608 	tty_add(tty, buf, len);
609 	if (tty->cx + width > tty->sx) {
610 		tty->cx = (tty->cx + width) - tty->sx;
611 		if (tty->cx <= tty->sx)
612 			tty->cy++;
613 		else
614 			tty->cx = tty->cy = UINT_MAX;
615 	} else
616 		tty->cx += width;
617 }
618 
619 static void
620 tty_set_italics(struct tty *tty)
621 {
622 	const char	*s;
623 
624 	if (tty_term_has(tty->term, TTYC_SITM)) {
625 		s = options_get_string(global_options, "default-terminal");
626 		if (strcmp(s, "screen") != 0 && strncmp(s, "screen-", 7) != 0) {
627 			tty_putcode(tty, TTYC_SITM);
628 			return;
629 		}
630 	}
631 	tty_putcode(tty, TTYC_SMSO);
632 }
633 
634 void
635 tty_set_title(struct tty *tty, const char *title)
636 {
637 	if (!tty_term_has(tty->term, TTYC_TSL) ||
638 	    !tty_term_has(tty->term, TTYC_FSL))
639 		return;
640 
641 	tty_putcode(tty, TTYC_TSL);
642 	tty_puts(tty, title);
643 	tty_putcode(tty, TTYC_FSL);
644 }
645 
646 static void
647 tty_force_cursor_colour(struct tty *tty, const char *ccolour)
648 {
649 	if (*ccolour == '\0')
650 		tty_putcode(tty, TTYC_CR);
651 	else
652 		tty_putcode_ptr1(tty, TTYC_CS, ccolour);
653 	free(tty->ccolour);
654 	tty->ccolour = xstrdup(ccolour);
655 }
656 
657 void
658 tty_update_mode(struct tty *tty, int mode, struct screen *s)
659 {
660 	struct client	*c = tty->client;
661 	int		 changed;
662 
663 	if (s != NULL && strcmp(s->ccolour, tty->ccolour) != 0)
664 		tty_force_cursor_colour(tty, s->ccolour);
665 
666 	if (tty->flags & TTY_NOCURSOR)
667 		mode &= ~MODE_CURSOR;
668 
669 	changed = mode ^ tty->mode;
670 	if (changed != 0)
671 		log_debug("%s: update mode %x to %x", c->name, tty->mode, mode);
672 
673 	if (changed & MODE_BLINKING) {
674 		if (tty_term_has(tty->term, TTYC_CVVIS))
675 			tty_putcode(tty, TTYC_CVVIS);
676 		else
677 			tty_putcode(tty, TTYC_CNORM);
678 		changed |= MODE_CURSOR;
679 	}
680 	if (changed & MODE_CURSOR) {
681 		if (mode & MODE_CURSOR)
682 			tty_putcode(tty, TTYC_CNORM);
683 		else
684 			tty_putcode(tty, TTYC_CIVIS);
685 	}
686 	if (s != NULL && tty->cstyle != s->cstyle) {
687 		if (tty_term_has(tty->term, TTYC_SS)) {
688 			if (s->cstyle == 0 && tty_term_has(tty->term, TTYC_SE))
689 				tty_putcode(tty, TTYC_SE);
690 			else
691 				tty_putcode1(tty, TTYC_SS, s->cstyle);
692 		}
693 		tty->cstyle = s->cstyle;
694 	}
695 	if ((changed & ALL_MOUSE_MODES) &&
696 	    tty_term_has(tty->term, TTYC_KMOUS)) {
697 		/*
698 		 * If the mouse modes have changed, clear any that are set and
699 		 * apply again. There are differences in how terminals track
700 		 * the various bits.
701 		 */
702 		if (tty->mode & MODE_MOUSE_SGR)
703 			tty_puts(tty, "\033[?1006l");
704 		if (tty->mode & MODE_MOUSE_STANDARD)
705 			tty_puts(tty, "\033[?1000l");
706 		if (tty->mode & MODE_MOUSE_BUTTON)
707 			tty_puts(tty, "\033[?1002l");
708 		if (tty->mode & MODE_MOUSE_ALL)
709 			tty_puts(tty, "\033[?1003l");
710 		if (mode & ALL_MOUSE_MODES)
711 			tty_puts(tty, "\033[?1006h");
712 		if (mode & MODE_MOUSE_STANDARD)
713 			tty_puts(tty, "\033[?1000h");
714 		if (mode & MODE_MOUSE_BUTTON)
715 			tty_puts(tty, "\033[?1002h");
716 		if (mode & MODE_MOUSE_ALL)
717 			tty_puts(tty, "\033[?1003h");
718 	}
719 	if (changed & MODE_BRACKETPASTE) {
720 		if (mode & MODE_BRACKETPASTE)
721 			tty_putcode(tty, TTYC_ENBP);
722 		else
723 			tty_putcode(tty, TTYC_DSBP);
724 	}
725 	tty->mode = mode;
726 }
727 
728 static void
729 tty_emulate_repeat(struct tty *tty, enum tty_code_code code,
730     enum tty_code_code code1, u_int n)
731 {
732 	if (tty_term_has(tty->term, code))
733 		tty_putcode1(tty, code, n);
734 	else {
735 		while (n-- > 0)
736 			tty_putcode(tty, code1);
737 	}
738 }
739 
740 static void
741 tty_repeat_space(struct tty *tty, u_int n)
742 {
743 	static char s[500];
744 
745 	if (*s != ' ')
746 		memset(s, ' ', sizeof s);
747 
748 	while (n > sizeof s) {
749 		tty_putn(tty, s, sizeof s, sizeof s);
750 		n -= sizeof s;
751 	}
752 	if (n != 0)
753 		tty_putn(tty, s, n, n);
754 }
755 
756 /* Is this window bigger than the terminal? */
757 int
758 tty_window_bigger(struct tty *tty)
759 {
760 	struct client	*c = tty->client;
761 	struct window	*w = c->session->curw->window;
762 
763 	return (tty->sx < w->sx || tty->sy - status_line_size(c) < w->sy);
764 }
765 
766 /* What offset should this window be drawn at? */
767 int
768 tty_window_offset(struct tty *tty, u_int *ox, u_int *oy, u_int *sx, u_int *sy)
769 {
770 	*ox = tty->oox;
771 	*oy = tty->ooy;
772 	*sx = tty->osx;
773 	*sy = tty->osy;
774 
775 	return (tty->oflag);
776 }
777 
778 /* What offset should this window be drawn at? */
779 static int
780 tty_window_offset1(struct tty *tty, u_int *ox, u_int *oy, u_int *sx, u_int *sy)
781 {
782 	struct client		*c = tty->client;
783 	struct window		*w = c->session->curw->window;
784 	struct window_pane	*wp = server_client_get_pane(c);
785 	u_int			 cx, cy, lines;
786 
787 	lines = status_line_size(c);
788 
789 	if (tty->sx >= w->sx && tty->sy - lines >= w->sy) {
790 		*ox = 0;
791 		*oy = 0;
792 		*sx = w->sx;
793 		*sy = w->sy;
794 
795 		c->pan_window = NULL;
796 		return (0);
797 	}
798 
799 	*sx = tty->sx;
800 	*sy = tty->sy - lines;
801 
802 	if (c->pan_window == w) {
803 		if (*sx >= w->sx)
804 			c->pan_ox = 0;
805 		else if (c->pan_ox + *sx > w->sx)
806 			c->pan_ox = w->sx - *sx;
807 		*ox = c->pan_ox;
808 		if (*sy >= w->sy)
809 			c->pan_oy = 0;
810 		else if (c->pan_oy + *sy > w->sy)
811 			c->pan_oy = w->sy - *sy;
812 		*oy = c->pan_oy;
813 		return (1);
814 	}
815 
816 	if (~wp->screen->mode & MODE_CURSOR) {
817 		*ox = 0;
818 		*oy = 0;
819 	} else {
820 		cx = wp->xoff + wp->screen->cx;
821 		cy = wp->yoff + wp->screen->cy;
822 
823 		if (cx < *sx)
824 			*ox = 0;
825 		else if (cx > w->sx - *sx)
826 			*ox = w->sx - *sx;
827 		else
828 			*ox = cx - *sx / 2;
829 
830 		if (cy < *sy)
831 			*oy = 0;
832 		else if (cy > w->sy - *sy)
833 			*oy = w->sy - *sy;
834 		else
835 			*oy = cy - *sy / 2;
836 	}
837 
838 	c->pan_window = NULL;
839 	return (1);
840 }
841 
842 /* Update stored offsets for a window and redraw if necessary. */
843 void
844 tty_update_window_offset(struct window *w)
845 {
846 	struct client	*c;
847 
848 	TAILQ_FOREACH(c, &clients, entry) {
849 		if (c->session != NULL && c->session->curw->window == w)
850 			tty_update_client_offset(c);
851 	}
852 }
853 
854 /* Update stored offsets for a client and redraw if necessary. */
855 void
856 tty_update_client_offset(struct client *c)
857 {
858 	u_int	ox, oy, sx, sy;
859 
860 	if (~c->flags & CLIENT_TERMINAL)
861 		return;
862 
863 	c->tty.oflag = tty_window_offset1(&c->tty, &ox, &oy, &sx, &sy);
864 	if (ox == c->tty.oox &&
865 	    oy == c->tty.ooy &&
866 	    sx == c->tty.osx &&
867 	    sy == c->tty.osy)
868 		return;
869 
870 	log_debug ("%s: %s offset has changed (%u,%u %ux%u -> %u,%u %ux%u)",
871 	    __func__, c->name, c->tty.oox, c->tty.ooy, c->tty.osx, c->tty.osy,
872 	    ox, oy, sx, sy);
873 
874 	c->tty.oox = ox;
875 	c->tty.ooy = oy;
876 	c->tty.osx = sx;
877 	c->tty.osy = sy;
878 
879 	c->flags |= (CLIENT_REDRAWWINDOW|CLIENT_REDRAWSTATUS);
880 }
881 
882 /* Get a palette entry. */
883 static int
884 tty_get_palette(int *palette, int c)
885 {
886 	int	new;
887 
888 	if (palette == NULL)
889 		return (-1);
890 
891 	new = -1;
892 	if (c < 8)
893 		new = palette[c];
894 	else if (c >= 90 && c <= 97)
895 		new = palette[8 + c - 90];
896 	else if (c & COLOUR_FLAG_256)
897 		new = palette[c & ~COLOUR_FLAG_256];
898 	if (new == 0)
899 		return (-1);
900 	return (new);
901 }
902 
903 /*
904  * Is the region large enough to be worth redrawing once later rather than
905  * probably several times now? Currently yes if it is more than 50% of the
906  * pane.
907  */
908 static int
909 tty_large_region(__unused struct tty *tty, const struct tty_ctx *ctx)
910 {
911 	return (ctx->orlower - ctx->orupper >= ctx->sy / 2);
912 }
913 
914 /*
915  * Return if BCE is needed but the terminal doesn't have it - it'll need to be
916  * emulated.
917  */
918 static int
919 tty_fake_bce(const struct tty *tty, const struct grid_cell *gc, u_int bg)
920 {
921 	if (tty_term_flag(tty->term, TTYC_BCE))
922 		return (0);
923 	if (!COLOUR_DEFAULT(bg) || !COLOUR_DEFAULT(gc->bg))
924 		return (1);
925 	return (0);
926 }
927 
928 /*
929  * Redraw scroll region using data from screen (already updated). Used when
930  * CSR not supported, or window is a pane that doesn't take up the full
931  * width of the terminal.
932  */
933 static void
934 tty_redraw_region(struct tty *tty, const struct tty_ctx *ctx)
935 {
936 	struct client		*c = tty->client;
937 	u_int			 i;
938 
939 	/*
940 	 * If region is large, schedule a redraw. In most cases this is likely
941 	 * to be followed by some more scrolling.
942 	 */
943 	if (tty_large_region(tty, ctx)) {
944 		log_debug("%s: %s large redraw", __func__, c->name);
945 		ctx->redraw_cb(ctx);
946 		return;
947 	}
948 
949 	if (ctx->ocy < ctx->orupper || ctx->ocy > ctx->orlower) {
950 		for (i = ctx->ocy; i < ctx->sy; i++)
951 			tty_draw_pane(tty, ctx, i);
952 	} else {
953 		for (i = ctx->orupper; i <= ctx->orlower; i++)
954 			tty_draw_pane(tty, ctx, i);
955 	}
956 }
957 
958 /* Is this position visible in the pane? */
959 static int
960 tty_is_visible(__unused struct tty *tty, const struct tty_ctx *ctx, u_int px,
961     u_int py, u_int nx, u_int ny)
962 {
963 	u_int	xoff = ctx->rxoff + px, yoff = ctx->ryoff + py;
964 
965 	if (!ctx->bigger)
966 		return (1);
967 
968 	if (xoff + nx <= ctx->wox || xoff >= ctx->wox + ctx->wsx ||
969 	    yoff + ny <= ctx->woy || yoff >= ctx->woy + ctx->wsy)
970 		return (0);
971 	return (1);
972 }
973 
974 /* Clamp line position to visible part of pane. */
975 static int
976 tty_clamp_line(struct tty *tty, const struct tty_ctx *ctx, u_int px, u_int py,
977     u_int nx, u_int *i, u_int *x, u_int *rx, u_int *ry)
978 {
979 	u_int	xoff = ctx->rxoff + px;
980 
981 	if (!tty_is_visible(tty, ctx, px, py, nx, 1))
982 		return (0);
983 	*ry = ctx->yoff + py - ctx->woy;
984 
985 	if (xoff >= ctx->wox && xoff + nx <= ctx->wox + ctx->wsx) {
986 		/* All visible. */
987 		*i = 0;
988 		*x = ctx->xoff + px - ctx->wox;
989 		*rx = nx;
990 	} else if (xoff < ctx->wox && xoff + nx > ctx->wox + ctx->wsx) {
991 		/* Both left and right not visible. */
992 		*i = ctx->wox;
993 		*x = 0;
994 		*rx = ctx->wsx;
995 	} else if (xoff < ctx->wox) {
996 		/* Left not visible. */
997 		*i = ctx->wox - (ctx->xoff + px);
998 		*x = 0;
999 		*rx = nx - *i;
1000 	} else {
1001 		/* Right not visible. */
1002 		*i = 0;
1003 		*x = (ctx->xoff + px) - ctx->wox;
1004 		*rx = ctx->wsx - *x;
1005 	}
1006 	if (*rx > nx)
1007 		fatalx("%s: x too big, %u > %u", __func__, *rx, nx);
1008 
1009 	return (1);
1010 }
1011 
1012 /* Clear a line. */
1013 static void
1014 tty_clear_line(struct tty *tty, const struct grid_cell *defaults, u_int py,
1015     u_int px, u_int nx, u_int bg)
1016 {
1017 	struct client	*c = tty->client;
1018 
1019 	log_debug("%s: %s, %u at %u,%u", __func__, c->name, nx, px, py);
1020 
1021 	/* Nothing to clear. */
1022 	if (nx == 0)
1023 		return;
1024 
1025 	/* If genuine BCE is available, can try escape sequences. */
1026 	if (!tty_fake_bce(tty, defaults, bg)) {
1027 		/* Off the end of the line, use EL if available. */
1028 		if (px + nx >= tty->sx && tty_term_has(tty->term, TTYC_EL)) {
1029 			tty_cursor(tty, px, py);
1030 			tty_putcode(tty, TTYC_EL);
1031 			return;
1032 		}
1033 
1034 		/* At the start of the line. Use EL1. */
1035 		if (px == 0 && tty_term_has(tty->term, TTYC_EL1)) {
1036 			tty_cursor(tty, px + nx - 1, py);
1037 			tty_putcode(tty, TTYC_EL1);
1038 			return;
1039 		}
1040 
1041 		/* Section of line. Use ECH if possible. */
1042 		if (tty_term_has(tty->term, TTYC_ECH)) {
1043 			tty_cursor(tty, px, py);
1044 			tty_putcode1(tty, TTYC_ECH, nx);
1045 			return;
1046 		}
1047 	}
1048 
1049 	/* Couldn't use an escape sequence, use spaces. */
1050 	tty_cursor(tty, px, py);
1051 	tty_repeat_space(tty, nx);
1052 }
1053 
1054 /* Clear a line, adjusting to visible part of pane. */
1055 static void
1056 tty_clear_pane_line(struct tty *tty, const struct tty_ctx *ctx, u_int py,
1057     u_int px, u_int nx, u_int bg)
1058 {
1059 	struct client	*c = tty->client;
1060 	u_int		 i, x, rx, ry;
1061 
1062 	log_debug("%s: %s, %u at %u,%u", __func__, c->name, nx, px, py);
1063 
1064 	if (tty_clamp_line(tty, ctx, px, py, nx, &i, &x, &rx, &ry))
1065 		tty_clear_line(tty, &ctx->defaults, ry, x, rx, bg);
1066 }
1067 
1068 /* Clamp area position to visible part of pane. */
1069 static int
1070 tty_clamp_area(struct tty *tty, const struct tty_ctx *ctx, u_int px, u_int py,
1071     u_int nx, u_int ny, u_int *i, u_int *j, u_int *x, u_int *y, u_int *rx,
1072     u_int *ry)
1073 {
1074 	u_int	xoff = ctx->rxoff + px, yoff = ctx->ryoff + py;
1075 
1076 	if (!tty_is_visible(tty, ctx, px, py, nx, ny))
1077 		return (0);
1078 
1079 	if (xoff >= ctx->wox && xoff + nx <= ctx->wox + ctx->wsx) {
1080 		/* All visible. */
1081 		*i = 0;
1082 		*x = ctx->xoff + px - ctx->wox;
1083 		*rx = nx;
1084 	} else if (xoff < ctx->wox && xoff + nx > ctx->wox + ctx->wsx) {
1085 		/* Both left and right not visible. */
1086 		*i = ctx->wox;
1087 		*x = 0;
1088 		*rx = ctx->wsx;
1089 	} else if (xoff < ctx->wox) {
1090 		/* Left not visible. */
1091 		*i = ctx->wox - (ctx->xoff + px);
1092 		*x = 0;
1093 		*rx = nx - *i;
1094 	} else {
1095 		/* Right not visible. */
1096 		*i = 0;
1097 		*x = (ctx->xoff + px) - ctx->wox;
1098 		*rx = ctx->wsx - *x;
1099 	}
1100 	if (*rx > nx)
1101 		fatalx("%s: x too big, %u > %u", __func__, *rx, nx);
1102 
1103 	if (yoff >= ctx->woy && yoff + ny <= ctx->woy + ctx->wsy) {
1104 		/* All visible. */
1105 		*j = 0;
1106 		*y = ctx->yoff + py - ctx->woy;
1107 		*ry = ny;
1108 	} else if (yoff < ctx->woy && yoff + ny > ctx->woy + ctx->wsy) {
1109 		/* Both top and bottom not visible. */
1110 		*j = ctx->woy;
1111 		*y = 0;
1112 		*ry = ctx->wsy;
1113 	} else if (yoff < ctx->woy) {
1114 		/* Top not visible. */
1115 		*j = ctx->woy - (ctx->yoff + py);
1116 		*y = 0;
1117 		*ry = ny - *j;
1118 	} else {
1119 		/* Bottom not visible. */
1120 		*j = 0;
1121 		*y = (ctx->yoff + py) - ctx->woy;
1122 		*ry = ctx->wsy - *y;
1123 	}
1124 	if (*ry > ny)
1125 		fatalx("%s: y too big, %u > %u", __func__, *ry, ny);
1126 
1127 	return (1);
1128 }
1129 
1130 /* Clear an area, adjusting to visible part of pane. */
1131 static void
1132 tty_clear_area(struct tty *tty, const struct grid_cell *defaults, u_int py,
1133     u_int ny, u_int px, u_int nx, u_int bg)
1134 {
1135 	struct client	*c = tty->client;
1136 	u_int		 yy;
1137 	char		 tmp[64];
1138 
1139 	log_debug("%s: %s, %u,%u at %u,%u", __func__, c->name, nx, ny, px, py);
1140 
1141 	/* Nothing to clear. */
1142 	if (nx == 0 || ny == 0)
1143 		return;
1144 
1145 	/* If genuine BCE is available, can try escape sequences. */
1146 	if (!tty_fake_bce(tty, defaults, bg)) {
1147 		/* Use ED if clearing off the bottom of the terminal. */
1148 		if (px == 0 &&
1149 		    px + nx >= tty->sx &&
1150 		    py + ny >= tty->sy &&
1151 		    tty_term_has(tty->term, TTYC_ED)) {
1152 			tty_cursor(tty, 0, py);
1153 			tty_putcode(tty, TTYC_ED);
1154 			return;
1155 		}
1156 
1157 		/*
1158 		 * On VT420 compatible terminals we can use DECFRA if the
1159 		 * background colour isn't default (because it doesn't work
1160 		 * after SGR 0).
1161 		 */
1162 		if ((tty->term->flags & TERM_DECFRA) && !COLOUR_DEFAULT(bg)) {
1163 			xsnprintf(tmp, sizeof tmp, "\033[32;%u;%u;%u;%u$x",
1164 			    py + 1, px + 1, py + ny, px + nx);
1165 			tty_puts(tty, tmp);
1166 			return;
1167 		}
1168 
1169 		/* Full lines can be scrolled away to clear them. */
1170 		if (px == 0 &&
1171 		    px + nx >= tty->sx &&
1172 		    ny > 2 &&
1173 		    tty_term_has(tty->term, TTYC_CSR) &&
1174 		    tty_term_has(tty->term, TTYC_INDN)) {
1175 			tty_region(tty, py, py + ny - 1);
1176 			tty_margin_off(tty);
1177 			tty_putcode1(tty, TTYC_INDN, ny);
1178 			return;
1179 		}
1180 
1181 		/*
1182 		 * If margins are supported, can just scroll the area off to
1183 		 * clear it.
1184 		 */
1185 		if (nx > 2 &&
1186 		    ny > 2 &&
1187 		    tty_term_has(tty->term, TTYC_CSR) &&
1188 		    tty_use_margin(tty) &&
1189 		    tty_term_has(tty->term, TTYC_INDN)) {
1190 			tty_region(tty, py, py + ny - 1);
1191 			tty_margin(tty, px, px + nx - 1);
1192 			tty_putcode1(tty, TTYC_INDN, ny);
1193 			return;
1194 		}
1195 	}
1196 
1197 	/* Couldn't use an escape sequence, loop over the lines. */
1198 	for (yy = py; yy < py + ny; yy++)
1199 		tty_clear_line(tty, defaults, yy, px, nx, bg);
1200 }
1201 
1202 /* Clear an area in a pane. */
1203 static void
1204 tty_clear_pane_area(struct tty *tty, const struct tty_ctx *ctx, u_int py,
1205     u_int ny, u_int px, u_int nx, u_int bg)
1206 {
1207 	u_int	i, j, x, y, rx, ry;
1208 
1209 	if (tty_clamp_area(tty, ctx, px, py, nx, ny, &i, &j, &x, &y, &rx, &ry))
1210 		tty_clear_area(tty, &ctx->defaults, y, ry, x, rx, bg);
1211 }
1212 
1213 static void
1214 tty_draw_pane(struct tty *tty, const struct tty_ctx *ctx, u_int py)
1215 {
1216 	struct screen	*s = ctx->s;
1217 	u_int		 nx = ctx->sx, i, x, rx, ry;
1218 
1219 	log_debug("%s: %s %u %d", __func__, tty->client->name, py, ctx->bigger);
1220 
1221 	if (!ctx->bigger) {
1222 		tty_draw_line(tty, s, 0, py, nx, ctx->xoff, ctx->yoff + py,
1223 		    &ctx->defaults, ctx->palette);
1224 		return;
1225 	}
1226 	if (tty_clamp_line(tty, ctx, 0, py, nx, &i, &x, &rx, &ry)) {
1227 		tty_draw_line(tty, s, i, py, rx, x, ry, &ctx->defaults,
1228 		    ctx->palette);
1229 	}
1230 }
1231 
1232 static const struct grid_cell *
1233 tty_check_codeset(struct tty *tty, const struct grid_cell *gc)
1234 {
1235 	static struct grid_cell	new;
1236 	int			c;
1237 
1238 	/* Characters less than 0x7f are always fine, no matter what. */
1239 	if (gc->data.size == 1 && *gc->data.data < 0x7f)
1240 		return (gc);
1241 
1242 	/* UTF-8 terminal and a UTF-8 character - fine. */
1243 	if (tty->client->flags & CLIENT_UTF8)
1244 		return (gc);
1245 	memcpy(&new, gc, sizeof new);
1246 
1247 	/* See if this can be mapped to an ACS character. */
1248 	c = tty_acs_reverse_get(tty, gc->data.data, gc->data.size);
1249 	if (c != -1) {
1250 		utf8_set(&new.data, c);
1251 		new.attr |= GRID_ATTR_CHARSET;
1252 		return (&new);
1253 	}
1254 
1255 	/* Replace by the right number of underscores. */
1256 	new.data.size = gc->data.width;
1257 	if (new.data.size > UTF8_SIZE)
1258 		new.data.size = UTF8_SIZE;
1259 	memset(new.data.data, '_', new.data.size);
1260 	return (&new);
1261 }
1262 
1263 static int
1264 tty_check_overlay(struct tty *tty, u_int px, u_int py)
1265 {
1266 	struct client	*c = tty->client;
1267 
1268 	if (c->overlay_check == NULL)
1269 		return (1);
1270 	return (c->overlay_check(c, px, py));
1271 }
1272 
1273 void
1274 tty_draw_line(struct tty *tty, struct screen *s, u_int px, u_int py, u_int nx,
1275     u_int atx, u_int aty, const struct grid_cell *defaults, int *palette)
1276 {
1277 	struct grid		*gd = s->grid;
1278 	struct grid_cell	 gc, last;
1279 	const struct grid_cell	*gcp;
1280 	struct grid_line	*gl;
1281 	u_int			 i, j, ux, sx, width;
1282 	int			 flags, cleared = 0, wrapped = 0;
1283 	char			 buf[512];
1284 	size_t			 len;
1285 	u_int			 cellsize;
1286 
1287 	log_debug("%s: px=%u py=%u nx=%u atx=%u aty=%u", __func__,
1288 	    px, py, nx, atx, aty);
1289 
1290 	/*
1291 	 * py is the line in the screen to draw.
1292 	 * px is the start x and nx is the width to draw.
1293 	 * atx,aty is the line on the terminal to draw it.
1294 	 */
1295 
1296 	flags = (tty->flags & TTY_NOCURSOR);
1297 	tty->flags |= TTY_NOCURSOR;
1298 	tty_update_mode(tty, tty->mode, s);
1299 
1300 	tty_region_off(tty);
1301 	tty_margin_off(tty);
1302 
1303 	/*
1304 	 * Clamp the width to cellsize - note this is not cellused, because
1305 	 * there may be empty background cells after it (from BCE).
1306 	 */
1307 	sx = screen_size_x(s);
1308 	if (nx > sx)
1309 		nx = sx;
1310 	cellsize = grid_get_line(gd, gd->hsize + py)->cellsize;
1311 	if (sx > cellsize)
1312 		sx = cellsize;
1313 	if (sx > tty->sx)
1314 		sx = tty->sx;
1315 	if (sx > nx)
1316 		sx = nx;
1317 	ux = 0;
1318 
1319 	if (py == 0)
1320 		gl = NULL;
1321 	else
1322 		gl = grid_get_line(gd, gd->hsize + py - 1);
1323 	if (gl == NULL ||
1324 	    (~gl->flags & GRID_LINE_WRAPPED) ||
1325 	    atx != 0 ||
1326 	    tty->cx < tty->sx ||
1327 	    nx < tty->sx) {
1328 		if (nx < tty->sx &&
1329 		    atx == 0 &&
1330 		    px + sx != nx &&
1331 		    tty_term_has(tty->term, TTYC_EL1) &&
1332 		    !tty_fake_bce(tty, defaults, 8)) {
1333 			tty_default_attributes(tty, defaults, palette, 8);
1334 			tty_cursor(tty, nx - 1, aty);
1335 			tty_putcode(tty, TTYC_EL1);
1336 			cleared = 1;
1337 		}
1338 	} else {
1339 		log_debug("%s: wrapped line %u", __func__, aty);
1340 		wrapped = 1;
1341 	}
1342 
1343 	memcpy(&last, &grid_default_cell, sizeof last);
1344 	len = 0;
1345 	width = 0;
1346 
1347 	for (i = 0; i < sx; i++) {
1348 		grid_view_get_cell(gd, px + i, py, &gc);
1349 		gcp = tty_check_codeset(tty, &gc);
1350 		if (len != 0 &&
1351 		    (!tty_check_overlay(tty, atx + ux + width, aty) ||
1352 		    (gcp->attr & GRID_ATTR_CHARSET) ||
1353 		    gcp->flags != last.flags ||
1354 		    gcp->attr != last.attr ||
1355 		    gcp->fg != last.fg ||
1356 		    gcp->bg != last.bg ||
1357 		    gcp->us != last.us ||
1358 		    ux + width + gcp->data.width > nx ||
1359 		    (sizeof buf) - len < gcp->data.size)) {
1360 			tty_attributes(tty, &last, defaults, palette);
1361 			if (last.flags & GRID_FLAG_CLEARED) {
1362 				log_debug("%s: %zu cleared", __func__, len);
1363 				tty_clear_line(tty, defaults, aty, atx + ux,
1364 				    width, last.bg);
1365 			} else {
1366 				if (!wrapped || atx != 0 || ux != 0)
1367 					tty_cursor(tty, atx + ux, aty);
1368 				tty_putn(tty, buf, len, width);
1369 			}
1370 			ux += width;
1371 
1372 			len = 0;
1373 			width = 0;
1374 			wrapped = 0;
1375 		}
1376 
1377 		if (gcp->flags & GRID_FLAG_SELECTED)
1378 			screen_select_cell(s, &last, gcp);
1379 		else
1380 			memcpy(&last, gcp, sizeof last);
1381 		if (!tty_check_overlay(tty, atx + ux, aty)) {
1382 			if (~gcp->flags & GRID_FLAG_PADDING)
1383 				ux += gcp->data.width;
1384 		} else if (ux + gcp->data.width > nx) {
1385 			tty_attributes(tty, &last, defaults, palette);
1386 			tty_cursor(tty, atx + ux, aty);
1387 			for (j = 0; j < gcp->data.width; j++) {
1388 				if (ux + j > nx)
1389 					break;
1390 				tty_putc(tty, ' ');
1391 				ux++;
1392 			}
1393 		} else if (gcp->attr & GRID_ATTR_CHARSET) {
1394 			tty_attributes(tty, &last, defaults, palette);
1395 			tty_cursor(tty, atx + ux, aty);
1396 			for (j = 0; j < gcp->data.size; j++)
1397 				tty_putc(tty, gcp->data.data[j]);
1398 			ux += gcp->data.width;
1399 		} else if (~gcp->flags & GRID_FLAG_PADDING) {
1400 			memcpy(buf + len, gcp->data.data, gcp->data.size);
1401 			len += gcp->data.size;
1402 			width += gcp->data.width;
1403 		}
1404 	}
1405 	if (len != 0 && ((~last.flags & GRID_FLAG_CLEARED) || last.bg != 8)) {
1406 		tty_attributes(tty, &last, defaults, palette);
1407 		if (last.flags & GRID_FLAG_CLEARED) {
1408 			log_debug("%s: %zu cleared (end)", __func__, len);
1409 			tty_clear_line(tty, defaults, aty, atx + ux, width,
1410 			    last.bg);
1411 		} else {
1412 			if (!wrapped || atx != 0 || ux != 0)
1413 				tty_cursor(tty, atx + ux, aty);
1414 			tty_putn(tty, buf, len, width);
1415 		}
1416 		ux += width;
1417 	}
1418 
1419 	if (!cleared && ux < nx) {
1420 		log_debug("%s: %u to end of line (%zu cleared)", __func__,
1421 		    nx - ux, len);
1422 		tty_default_attributes(tty, defaults, palette, 8);
1423 		tty_clear_line(tty, defaults, aty, atx + ux, nx - ux, 8);
1424 	}
1425 
1426 	tty->flags = (tty->flags & ~TTY_NOCURSOR) | flags;
1427 	tty_update_mode(tty, tty->mode, s);
1428 }
1429 
1430 void
1431 tty_sync_start(struct tty *tty)
1432 {
1433 	if (tty->flags & TTY_BLOCK)
1434 		return;
1435 	if (tty->flags & TTY_SYNCING)
1436 		return;
1437 	tty->flags |= TTY_SYNCING;
1438 
1439 	if (tty_term_has(tty->term, TTYC_SYNC)) {
1440 		log_debug("%s sync start", tty->client->name);
1441 		tty_putcode1(tty, TTYC_SYNC, 1);
1442 	}
1443 }
1444 
1445 void
1446 tty_sync_end(struct tty *tty)
1447 {
1448 	if (tty->flags & TTY_BLOCK)
1449 		return;
1450 	if (~tty->flags & TTY_SYNCING)
1451 		return;
1452 	tty->flags &= ~TTY_SYNCING;
1453 
1454 	if (tty_term_has(tty->term, TTYC_SYNC)) {
1455  		log_debug("%s sync end", tty->client->name);
1456 		tty_putcode1(tty, TTYC_SYNC, 2);
1457 	}
1458 }
1459 
1460 static int
1461 tty_client_ready(struct client *c)
1462 {
1463 	if (c->session == NULL || c->tty.term == NULL)
1464 		return (0);
1465 	if (c->flags & (CLIENT_REDRAWWINDOW|CLIENT_SUSPENDED))
1466 		return (0);
1467 	if (c->tty.flags & TTY_FREEZE)
1468 		return (0);
1469 	return (1);
1470 }
1471 
1472 void
1473 tty_write(void (*cmdfn)(struct tty *, const struct tty_ctx *),
1474     struct tty_ctx *ctx)
1475 {
1476 	struct client	*c;
1477 	int		 state;
1478 
1479 	if (ctx->set_client_cb == NULL)
1480 		return;
1481 	TAILQ_FOREACH(c, &clients, entry) {
1482 		if (!tty_client_ready(c))
1483 			continue;
1484 		state = ctx->set_client_cb(ctx, c);
1485 		if (state == -1)
1486 			break;
1487 		if (state == 0)
1488 			continue;
1489 		cmdfn(&c->tty, ctx);
1490 	}
1491 }
1492 
1493 void
1494 tty_cmd_insertcharacter(struct tty *tty, const struct tty_ctx *ctx)
1495 {
1496 	if (ctx->bigger ||
1497 	    !tty_full_width(tty, ctx) ||
1498 	    tty_fake_bce(tty, &ctx->defaults, ctx->bg) ||
1499 	    (!tty_term_has(tty->term, TTYC_ICH) &&
1500 	    !tty_term_has(tty->term, TTYC_ICH1))) {
1501 		tty_draw_pane(tty, ctx, ctx->ocy);
1502 		return;
1503 	}
1504 
1505 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1506 
1507 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1508 
1509 	tty_emulate_repeat(tty, TTYC_ICH, TTYC_ICH1, ctx->num);
1510 }
1511 
1512 void
1513 tty_cmd_deletecharacter(struct tty *tty, const struct tty_ctx *ctx)
1514 {
1515 	if (ctx->bigger ||
1516 	    !tty_full_width(tty, ctx) ||
1517 	    tty_fake_bce(tty, &ctx->defaults, ctx->bg) ||
1518 	    (!tty_term_has(tty->term, TTYC_DCH) &&
1519 	    !tty_term_has(tty->term, TTYC_DCH1))) {
1520 		tty_draw_pane(tty, ctx, ctx->ocy);
1521 		return;
1522 	}
1523 
1524 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1525 
1526 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1527 
1528 	tty_emulate_repeat(tty, TTYC_DCH, TTYC_DCH1, ctx->num);
1529 }
1530 
1531 void
1532 tty_cmd_clearcharacter(struct tty *tty, const struct tty_ctx *ctx)
1533 {
1534 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1535 
1536 	tty_clear_pane_line(tty, ctx, ctx->ocy, ctx->ocx, ctx->num, ctx->bg);
1537 }
1538 
1539 void
1540 tty_cmd_insertline(struct tty *tty, const struct tty_ctx *ctx)
1541 {
1542 	if (ctx->bigger ||
1543 	    !tty_full_width(tty, ctx) ||
1544 	    tty_fake_bce(tty, &ctx->defaults, ctx->bg) ||
1545 	    !tty_term_has(tty->term, TTYC_CSR) ||
1546 	    !tty_term_has(tty->term, TTYC_IL1) ||
1547 	    ctx->sx == 1 ||
1548 	    ctx->sy == 1) {
1549 		tty_redraw_region(tty, ctx);
1550 		return;
1551 	}
1552 
1553 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1554 
1555 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1556 	tty_margin_off(tty);
1557 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1558 
1559 	tty_emulate_repeat(tty, TTYC_IL, TTYC_IL1, ctx->num);
1560 	tty->cx = tty->cy = UINT_MAX;
1561 }
1562 
1563 void
1564 tty_cmd_deleteline(struct tty *tty, const struct tty_ctx *ctx)
1565 {
1566 	if (ctx->bigger ||
1567 	    !tty_full_width(tty, ctx) ||
1568 	    tty_fake_bce(tty, &ctx->defaults, ctx->bg) ||
1569 	    !tty_term_has(tty->term, TTYC_CSR) ||
1570 	    !tty_term_has(tty->term, TTYC_DL1) ||
1571 	    ctx->sx == 1 ||
1572 	    ctx->sy == 1) {
1573 		tty_redraw_region(tty, ctx);
1574 		return;
1575 	}
1576 
1577 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1578 
1579 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1580 	tty_margin_off(tty);
1581 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1582 
1583 	tty_emulate_repeat(tty, TTYC_DL, TTYC_DL1, ctx->num);
1584 	tty->cx = tty->cy = UINT_MAX;
1585 }
1586 
1587 void
1588 tty_cmd_clearline(struct tty *tty, const struct tty_ctx *ctx)
1589 {
1590 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1591 
1592 	tty_clear_pane_line(tty, ctx, ctx->ocy, 0, ctx->sx, ctx->bg);
1593 }
1594 
1595 void
1596 tty_cmd_clearendofline(struct tty *tty, const struct tty_ctx *ctx)
1597 {
1598 	u_int	nx = ctx->sx - ctx->ocx;
1599 
1600 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1601 
1602 	tty_clear_pane_line(tty, ctx, ctx->ocy, ctx->ocx, nx, ctx->bg);
1603 }
1604 
1605 void
1606 tty_cmd_clearstartofline(struct tty *tty, const struct tty_ctx *ctx)
1607 {
1608 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1609 
1610 	tty_clear_pane_line(tty, ctx, ctx->ocy, 0, ctx->ocx + 1, ctx->bg);
1611 }
1612 
1613 void
1614 tty_cmd_reverseindex(struct tty *tty, const struct tty_ctx *ctx)
1615 {
1616 	if (ctx->ocy != ctx->orupper)
1617 		return;
1618 
1619 	if (ctx->bigger ||
1620 	    (!tty_full_width(tty, ctx) && !tty_use_margin(tty)) ||
1621 	    tty_fake_bce(tty, &ctx->defaults, 8) ||
1622 	    !tty_term_has(tty->term, TTYC_CSR) ||
1623 	    (!tty_term_has(tty->term, TTYC_RI) &&
1624 	    !tty_term_has(tty->term, TTYC_RIN)) ||
1625 	    ctx->sx == 1 ||
1626 	    ctx->sy == 1) {
1627 		tty_redraw_region(tty, ctx);
1628 		return;
1629 	}
1630 
1631 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1632 
1633 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1634 	tty_margin_pane(tty, ctx);
1635 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->orupper);
1636 
1637 	if (tty_term_has(tty->term, TTYC_RI))
1638 		tty_putcode(tty, TTYC_RI);
1639 	else
1640 		tty_putcode1(tty, TTYC_RIN, 1);
1641 }
1642 
1643 void
1644 tty_cmd_linefeed(struct tty *tty, const struct tty_ctx *ctx)
1645 {
1646 	if (ctx->ocy != ctx->orlower)
1647 		return;
1648 
1649 	if (ctx->bigger ||
1650 	    (!tty_full_width(tty, ctx) && !tty_use_margin(tty)) ||
1651 	    tty_fake_bce(tty, &ctx->defaults, 8) ||
1652 	    !tty_term_has(tty->term, TTYC_CSR) ||
1653 	    ctx->sx == 1 ||
1654 	    ctx->sy == 1) {
1655 		tty_redraw_region(tty, ctx);
1656 		return;
1657 	}
1658 
1659 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1660 
1661 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1662 	tty_margin_pane(tty, ctx);
1663 
1664 	/*
1665 	 * If we want to wrap a pane while using margins, the cursor needs to
1666 	 * be exactly on the right of the region. If the cursor is entirely off
1667 	 * the edge - move it back to the right. Some terminals are funny about
1668 	 * this and insert extra spaces, so only use the right if margins are
1669 	 * enabled.
1670 	 */
1671 	if (ctx->xoff + ctx->ocx > tty->rright) {
1672 		if (!tty_use_margin(tty))
1673 			tty_cursor(tty, 0, ctx->yoff + ctx->ocy);
1674 		else
1675 			tty_cursor(tty, tty->rright, ctx->yoff + ctx->ocy);
1676 	} else
1677 		tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1678 
1679 	tty_putc(tty, '\n');
1680 }
1681 
1682 void
1683 tty_cmd_scrollup(struct tty *tty, const struct tty_ctx *ctx)
1684 {
1685 	u_int	i;
1686 
1687 	if (ctx->bigger ||
1688 	    (!tty_full_width(tty, ctx) && !tty_use_margin(tty)) ||
1689 	    tty_fake_bce(tty, &ctx->defaults, 8) ||
1690 	    !tty_term_has(tty->term, TTYC_CSR) ||
1691 	    ctx->sx == 1 ||
1692 	    ctx->sy == 1) {
1693 		tty_redraw_region(tty, ctx);
1694 		return;
1695 	}
1696 
1697 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1698 
1699 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1700 	tty_margin_pane(tty, ctx);
1701 
1702 	if (ctx->num == 1 || !tty_term_has(tty->term, TTYC_INDN)) {
1703 		if (!tty_use_margin(tty))
1704 			tty_cursor(tty, 0, tty->rlower);
1705 		else
1706 			tty_cursor(tty, tty->rright, tty->rlower);
1707 		for (i = 0; i < ctx->num; i++)
1708 			tty_putc(tty, '\n');
1709 	} else {
1710 		if (tty->cy == UINT_MAX)
1711 			tty_cursor(tty, 0, 0);
1712 		else
1713 			tty_cursor(tty, 0, tty->cy);
1714 		tty_putcode1(tty, TTYC_INDN, ctx->num);
1715 	}
1716 }
1717 
1718 void
1719 tty_cmd_scrolldown(struct tty *tty, const struct tty_ctx *ctx)
1720 {
1721 	u_int	i;
1722 
1723 	if (ctx->bigger ||
1724 	    (!tty_full_width(tty, ctx) && !tty_use_margin(tty)) ||
1725 	    tty_fake_bce(tty, &ctx->defaults, 8) ||
1726 	    !tty_term_has(tty->term, TTYC_CSR) ||
1727 	    (!tty_term_has(tty->term, TTYC_RI) &&
1728 	    !tty_term_has(tty->term, TTYC_RIN)) ||
1729 	    ctx->sx == 1 ||
1730 	    ctx->sy == 1) {
1731 		tty_redraw_region(tty, ctx);
1732 		return;
1733 	}
1734 
1735 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1736 
1737 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1738 	tty_margin_pane(tty, ctx);
1739 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->orupper);
1740 
1741 	if (tty_term_has(tty->term, TTYC_RIN))
1742 		tty_putcode1(tty, TTYC_RIN, ctx->num);
1743 	else {
1744 		for (i = 0; i < ctx->num; i++)
1745 			tty_putcode(tty, TTYC_RI);
1746 	}
1747 }
1748 
1749 void
1750 tty_cmd_clearendofscreen(struct tty *tty, const struct tty_ctx *ctx)
1751 {
1752 	u_int	px, py, nx, ny;
1753 
1754 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1755 
1756 	tty_region_pane(tty, ctx, 0, ctx->sy - 1);
1757 	tty_margin_off(tty);
1758 
1759 	px = 0;
1760 	nx = ctx->sx;
1761 	py = ctx->ocy + 1;
1762 	ny = ctx->sy - ctx->ocy - 1;
1763 
1764 	tty_clear_pane_area(tty, ctx, py, ny, px, nx, ctx->bg);
1765 
1766 	px = ctx->ocx;
1767 	nx = ctx->sx - ctx->ocx;
1768 	py = ctx->ocy;
1769 
1770 	tty_clear_pane_line(tty, ctx, py, px, nx, ctx->bg);
1771 }
1772 
1773 void
1774 tty_cmd_clearstartofscreen(struct tty *tty, const struct tty_ctx *ctx)
1775 {
1776 	u_int	px, py, nx, ny;
1777 
1778 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1779 
1780 	tty_region_pane(tty, ctx, 0, ctx->sy - 1);
1781 	tty_margin_off(tty);
1782 
1783 	px = 0;
1784 	nx = ctx->sx;
1785 	py = 0;
1786 	ny = ctx->ocy;
1787 
1788 	tty_clear_pane_area(tty, ctx, py, ny, px, nx, ctx->bg);
1789 
1790 	px = 0;
1791 	nx = ctx->ocx + 1;
1792 	py = ctx->ocy;
1793 
1794 	tty_clear_pane_line(tty, ctx, py, px, nx, ctx->bg);
1795 }
1796 
1797 void
1798 tty_cmd_clearscreen(struct tty *tty, const struct tty_ctx *ctx)
1799 {
1800 	u_int	px, py, nx, ny;
1801 
1802 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg);
1803 
1804 	tty_region_pane(tty, ctx, 0, ctx->sy - 1);
1805 	tty_margin_off(tty);
1806 
1807 	px = 0;
1808 	nx = ctx->sx;
1809 	py = 0;
1810 	ny = ctx->sy;
1811 
1812 	tty_clear_pane_area(tty, ctx, py, ny, px, nx, ctx->bg);
1813 }
1814 
1815 void
1816 tty_cmd_alignmenttest(struct tty *tty, const struct tty_ctx *ctx)
1817 {
1818 	u_int	i, j;
1819 
1820 	if (ctx->bigger) {
1821 		ctx->redraw_cb(ctx);
1822 		return;
1823 	}
1824 
1825 	tty_attributes(tty, &grid_default_cell, &ctx->defaults, ctx->palette);
1826 
1827 	tty_region_pane(tty, ctx, 0, ctx->sy - 1);
1828 	tty_margin_off(tty);
1829 
1830 	for (j = 0; j < ctx->sy; j++) {
1831 		tty_cursor_pane(tty, ctx, 0, j);
1832 		for (i = 0; i < ctx->sx; i++)
1833 			tty_putc(tty, 'E');
1834 	}
1835 }
1836 
1837 void
1838 tty_cmd_cell(struct tty *tty, const struct tty_ctx *ctx)
1839 {
1840 	if (!tty_is_visible(tty, ctx, ctx->ocx, ctx->ocy, 1, 1))
1841 		return;
1842 
1843 	if (ctx->xoff + ctx->ocx - ctx->wox > tty->sx - 1 &&
1844 	    ctx->ocy == ctx->orlower &&
1845 	    tty_full_width(tty, ctx))
1846 		tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1847 
1848 	tty_margin_off(tty);
1849 	tty_cursor_pane_unless_wrap(tty, ctx, ctx->ocx, ctx->ocy);
1850 
1851 	tty_cell(tty, ctx->cell, &ctx->defaults, ctx->palette);
1852 }
1853 
1854 void
1855 tty_cmd_cells(struct tty *tty, const struct tty_ctx *ctx)
1856 {
1857 	if (!tty_is_visible(tty, ctx, ctx->ocx, ctx->ocy, ctx->num, 1))
1858 		return;
1859 
1860 	if (ctx->bigger &&
1861 	    (ctx->xoff + ctx->ocx < ctx->wox ||
1862 	    ctx->xoff + ctx->ocx + ctx->num > ctx->wox + ctx->wsx)) {
1863 		if (!ctx->wrapped ||
1864 		    !tty_full_width(tty, ctx) ||
1865 		    (tty->term->flags & TERM_NOAM) ||
1866 		    ctx->xoff + ctx->ocx != 0 ||
1867 		    ctx->yoff + ctx->ocy != tty->cy + 1 ||
1868 		    tty->cx < tty->sx ||
1869 		    tty->cy == tty->rlower)
1870 			tty_draw_pane(tty, ctx, ctx->ocy);
1871 		else
1872 			ctx->redraw_cb(ctx);
1873 		return;
1874 	}
1875 
1876 	tty_margin_off(tty);
1877 	tty_cursor_pane_unless_wrap(tty, ctx, ctx->ocx, ctx->ocy);
1878 
1879 	tty_attributes(tty, ctx->cell, &ctx->defaults, ctx->palette);
1880 	tty_putn(tty, ctx->ptr, ctx->num, ctx->num);
1881 }
1882 
1883 void
1884 tty_cmd_setselection(struct tty *tty, const struct tty_ctx *ctx)
1885 {
1886 	tty_set_selection(tty, ctx->ptr, ctx->num);
1887 }
1888 
1889 void
1890 tty_set_selection(struct tty *tty, const char *buf, size_t len)
1891 {
1892 	char	*encoded;
1893 	size_t	 size;
1894 
1895 	if (~tty->flags & TTY_STARTED)
1896 		return;
1897 	if (!tty_term_has(tty->term, TTYC_MS))
1898 		return;
1899 
1900 	size = 4 * ((len + 2) / 3) + 1; /* storage for base64 */
1901 	encoded = xmalloc(size);
1902 
1903 	b64_ntop(buf, len, encoded, size);
1904 	tty_putcode_ptr2(tty, TTYC_MS, "", encoded);
1905 
1906 	free(encoded);
1907 }
1908 
1909 void
1910 tty_cmd_rawstring(struct tty *tty, const struct tty_ctx *ctx)
1911 {
1912 	tty_add(tty, ctx->ptr, ctx->num);
1913 	tty_invalidate(tty);
1914 }
1915 
1916 void
1917 tty_cmd_syncstart(struct tty *tty, __unused const struct tty_ctx *ctx)
1918 {
1919 	tty_sync_start(tty);
1920 }
1921 
1922 void
1923 tty_cell(struct tty *tty, const struct grid_cell *gc,
1924     const struct grid_cell *defaults, int *palette)
1925 {
1926 	const struct grid_cell	*gcp;
1927 
1928 	/* Skip last character if terminal is stupid. */
1929 	if ((tty->term->flags & TERM_NOAM) &&
1930 	    tty->cy == tty->sy - 1 &&
1931 	    tty->cx == tty->sx - 1)
1932 		return;
1933 
1934 	/* If this is a padding character, do nothing. */
1935 	if (gc->flags & GRID_FLAG_PADDING)
1936 		return;
1937 
1938 	/* Check the output codeset and apply attributes. */
1939 	gcp = tty_check_codeset(tty, gc);
1940 	tty_attributes(tty, gcp, defaults, palette);
1941 
1942 	/* If it is a single character, write with putc to handle ACS. */
1943 	if (gcp->data.size == 1) {
1944 		tty_attributes(tty, gcp, defaults, palette);
1945 		if (*gcp->data.data < 0x20 || *gcp->data.data == 0x7f)
1946 			return;
1947 		tty_putc(tty, *gcp->data.data);
1948 		return;
1949 	}
1950 
1951 	/* Write the data. */
1952 	tty_putn(tty, gcp->data.data, gcp->data.size, gcp->data.width);
1953 }
1954 
1955 void
1956 tty_reset(struct tty *tty)
1957 {
1958 	struct grid_cell	*gc = &tty->cell;
1959 
1960 	if (!grid_cells_equal(gc, &grid_default_cell)) {
1961 		if ((gc->attr & GRID_ATTR_CHARSET) && tty_acs_needed(tty))
1962 			tty_putcode(tty, TTYC_RMACS);
1963 		tty_putcode(tty, TTYC_SGR0);
1964 		memcpy(gc, &grid_default_cell, sizeof *gc);
1965 	}
1966 	memcpy(&tty->last_cell, &grid_default_cell, sizeof tty->last_cell);
1967 }
1968 
1969 static void
1970 tty_invalidate(struct tty *tty)
1971 {
1972 	memcpy(&tty->cell, &grid_default_cell, sizeof tty->cell);
1973 	memcpy(&tty->last_cell, &grid_default_cell, sizeof tty->last_cell);
1974 
1975 	tty->cx = tty->cy = UINT_MAX;
1976 	tty->rupper = tty->rleft = UINT_MAX;
1977 	tty->rlower = tty->rright = UINT_MAX;
1978 
1979 	if (tty->flags & TTY_STARTED) {
1980 		if (tty_use_margin(tty))
1981 			tty_putcode(tty, TTYC_ENMG);
1982 		tty_putcode(tty, TTYC_SGR0);
1983 
1984 		tty->mode = ALL_MODES;
1985 		tty_update_mode(tty, MODE_CURSOR, NULL);
1986 
1987 		tty_cursor(tty, 0, 0);
1988 		tty_region_off(tty);
1989 		tty_margin_off(tty);
1990 	} else
1991 		tty->mode = MODE_CURSOR;
1992 }
1993 
1994 /* Turn off margin. */
1995 void
1996 tty_region_off(struct tty *tty)
1997 {
1998 	tty_region(tty, 0, tty->sy - 1);
1999 }
2000 
2001 /* Set region inside pane. */
2002 static void
2003 tty_region_pane(struct tty *tty, const struct tty_ctx *ctx, u_int rupper,
2004     u_int rlower)
2005 {
2006 	tty_region(tty, ctx->yoff + rupper - ctx->woy,
2007 	    ctx->yoff + rlower - ctx->woy);
2008 }
2009 
2010 /* Set region at absolute position. */
2011 static void
2012 tty_region(struct tty *tty, u_int rupper, u_int rlower)
2013 {
2014 	if (tty->rlower == rlower && tty->rupper == rupper)
2015 		return;
2016 	if (!tty_term_has(tty->term, TTYC_CSR))
2017 		return;
2018 
2019 	tty->rupper = rupper;
2020 	tty->rlower = rlower;
2021 
2022 	/*
2023 	 * Some terminals (such as PuTTY) do not correctly reset the cursor to
2024 	 * 0,0 if it is beyond the last column (they do not reset their wrap
2025 	 * flag so further output causes a line feed). As a workaround, do an
2026 	 * explicit move to 0 first.
2027 	 */
2028 	if (tty->cx >= tty->sx) {
2029 		if (tty->cy == UINT_MAX)
2030 			tty_cursor(tty, 0, 0);
2031 		else
2032 			tty_cursor(tty, 0, tty->cy);
2033 	}
2034 
2035 	tty_putcode2(tty, TTYC_CSR, tty->rupper, tty->rlower);
2036 	tty->cx = tty->cy = UINT_MAX;
2037 }
2038 
2039 /* Turn off margin. */
2040 void
2041 tty_margin_off(struct tty *tty)
2042 {
2043 	tty_margin(tty, 0, tty->sx - 1);
2044 }
2045 
2046 /* Set margin inside pane. */
2047 static void
2048 tty_margin_pane(struct tty *tty, const struct tty_ctx *ctx)
2049 {
2050 	tty_margin(tty, ctx->xoff - ctx->wox,
2051 	    ctx->xoff + ctx->sx - 1 - ctx->wox);
2052 }
2053 
2054 /* Set margin at absolute position. */
2055 static void
2056 tty_margin(struct tty *tty, u_int rleft, u_int rright)
2057 {
2058 	if (!tty_use_margin(tty))
2059 		return;
2060 	if (tty->rleft == rleft && tty->rright == rright)
2061 		return;
2062 
2063 	tty_putcode2(tty, TTYC_CSR, tty->rupper, tty->rlower);
2064 
2065 	tty->rleft = rleft;
2066 	tty->rright = rright;
2067 
2068 	if (rleft == 0 && rright == tty->sx - 1)
2069 		tty_putcode(tty, TTYC_CLMG);
2070 	else
2071 		tty_putcode2(tty, TTYC_CMG, rleft, rright);
2072 	tty->cx = tty->cy = UINT_MAX;
2073 }
2074 
2075 /*
2076  * Move the cursor, unless it would wrap itself when the next character is
2077  * printed.
2078  */
2079 static void
2080 tty_cursor_pane_unless_wrap(struct tty *tty, const struct tty_ctx *ctx,
2081     u_int cx, u_int cy)
2082 {
2083 	if (!ctx->wrapped ||
2084 	    !tty_full_width(tty, ctx) ||
2085 	    (tty->term->flags & TERM_NOAM) ||
2086 	    ctx->xoff + cx != 0 ||
2087 	    ctx->yoff + cy != tty->cy + 1 ||
2088 	    tty->cx < tty->sx ||
2089 	    tty->cy == tty->rlower)
2090 		tty_cursor_pane(tty, ctx, cx, cy);
2091 	else
2092 		log_debug("%s: will wrap at %u,%u", __func__, tty->cx, tty->cy);
2093 }
2094 
2095 /* Move cursor inside pane. */
2096 static void
2097 tty_cursor_pane(struct tty *tty, const struct tty_ctx *ctx, u_int cx, u_int cy)
2098 {
2099 	tty_cursor(tty, ctx->xoff + cx - ctx->wox, ctx->yoff + cy - ctx->woy);
2100 }
2101 
2102 /* Move cursor to absolute position. */
2103 void
2104 tty_cursor(struct tty *tty, u_int cx, u_int cy)
2105 {
2106 	struct tty_term	*term = tty->term;
2107 	u_int		 thisx, thisy;
2108 	int		 change;
2109 
2110 	if (tty->flags & TTY_BLOCK)
2111 		return;
2112 
2113 	if (cx > tty->sx - 1)
2114 		cx = tty->sx - 1;
2115 
2116 	thisx = tty->cx;
2117 	thisy = tty->cy;
2118 
2119 	/* No change. */
2120 	if (cx == thisx && cy == thisy)
2121 		return;
2122 
2123 	/* Very end of the line, just use absolute movement. */
2124 	if (thisx > tty->sx - 1)
2125 		goto absolute;
2126 
2127 	/* Move to home position (0, 0). */
2128 	if (cx == 0 && cy == 0 && tty_term_has(term, TTYC_HOME)) {
2129 		tty_putcode(tty, TTYC_HOME);
2130 		goto out;
2131 	}
2132 
2133 	/* Zero on the next line. */
2134 	if (cx == 0 && cy == thisy + 1 && thisy != tty->rlower &&
2135 	    (!tty_use_margin(tty) || tty->rleft == 0)) {
2136 		tty_putc(tty, '\r');
2137 		tty_putc(tty, '\n');
2138 		goto out;
2139 	}
2140 
2141 	/* Moving column or row. */
2142 	if (cy == thisy) {
2143 		/*
2144 		 * Moving column only, row staying the same.
2145 		 */
2146 
2147 		/* To left edge. */
2148 		if (cx == 0 && (!tty_use_margin(tty) || tty->rleft == 0)) {
2149 			tty_putc(tty, '\r');
2150 			goto out;
2151 		}
2152 
2153 		/* One to the left. */
2154 		if (cx == thisx - 1 && tty_term_has(term, TTYC_CUB1)) {
2155 			tty_putcode(tty, TTYC_CUB1);
2156 			goto out;
2157 		}
2158 
2159 		/* One to the right. */
2160 		if (cx == thisx + 1 && tty_term_has(term, TTYC_CUF1)) {
2161 			tty_putcode(tty, TTYC_CUF1);
2162 			goto out;
2163 		}
2164 
2165 		/* Calculate difference. */
2166 		change = thisx - cx;	/* +ve left, -ve right */
2167 
2168 		/*
2169 		 * Use HPA if change is larger than absolute, otherwise move
2170 		 * the cursor with CUB/CUF.
2171 		 */
2172 		if ((u_int) abs(change) > cx && tty_term_has(term, TTYC_HPA)) {
2173 			tty_putcode1(tty, TTYC_HPA, cx);
2174 			goto out;
2175 		} else if (change > 0 &&
2176 		    tty_term_has(term, TTYC_CUB) &&
2177 		    !tty_use_margin(tty)) {
2178 			if (change == 2 && tty_term_has(term, TTYC_CUB1)) {
2179 				tty_putcode(tty, TTYC_CUB1);
2180 				tty_putcode(tty, TTYC_CUB1);
2181 				goto out;
2182 			}
2183 			tty_putcode1(tty, TTYC_CUB, change);
2184 			goto out;
2185 		} else if (change < 0 &&
2186 		    tty_term_has(term, TTYC_CUF) &&
2187 		    !tty_use_margin(tty)) {
2188 			tty_putcode1(tty, TTYC_CUF, -change);
2189 			goto out;
2190 		}
2191 	} else if (cx == thisx) {
2192 		/*
2193 		 * Moving row only, column staying the same.
2194 		 */
2195 
2196 		/* One above. */
2197 		if (thisy != tty->rupper &&
2198 		    cy == thisy - 1 && tty_term_has(term, TTYC_CUU1)) {
2199 			tty_putcode(tty, TTYC_CUU1);
2200 			goto out;
2201 		}
2202 
2203 		/* One below. */
2204 		if (thisy != tty->rlower &&
2205 		    cy == thisy + 1 && tty_term_has(term, TTYC_CUD1)) {
2206 			tty_putcode(tty, TTYC_CUD1);
2207 			goto out;
2208 		}
2209 
2210 		/* Calculate difference. */
2211 		change = thisy - cy;	/* +ve up, -ve down */
2212 
2213 		/*
2214 		 * Try to use VPA if change is larger than absolute or if this
2215 		 * change would cross the scroll region, otherwise use CUU/CUD.
2216 		 */
2217 		if ((u_int) abs(change) > cy ||
2218 		    (change < 0 && cy - change > tty->rlower) ||
2219 		    (change > 0 && cy - change < tty->rupper)) {
2220 			    if (tty_term_has(term, TTYC_VPA)) {
2221 				    tty_putcode1(tty, TTYC_VPA, cy);
2222 				    goto out;
2223 			    }
2224 		} else if (change > 0 && tty_term_has(term, TTYC_CUU)) {
2225 			tty_putcode1(tty, TTYC_CUU, change);
2226 			goto out;
2227 		} else if (change < 0 && tty_term_has(term, TTYC_CUD)) {
2228 			tty_putcode1(tty, TTYC_CUD, -change);
2229 			goto out;
2230 		}
2231 	}
2232 
2233 absolute:
2234 	/* Absolute movement. */
2235 	tty_putcode2(tty, TTYC_CUP, cy, cx);
2236 
2237 out:
2238 	tty->cx = cx;
2239 	tty->cy = cy;
2240 }
2241 
2242 void
2243 tty_attributes(struct tty *tty, const struct grid_cell *gc,
2244     const struct grid_cell *defaults, int *palette)
2245 {
2246 	struct grid_cell	*tc = &tty->cell, gc2;
2247 	int			 changed;
2248 
2249 	/* Copy cell and update default colours. */
2250 	memcpy(&gc2, gc, sizeof gc2);
2251 	if (gc2.fg == 8)
2252 		gc2.fg = defaults->fg;
2253 	if (gc2.bg == 8)
2254 		gc2.bg = defaults->bg;
2255 
2256 	/* Ignore cell if it is the same as the last one. */
2257 	if (gc2.attr == tty->last_cell.attr &&
2258 	    gc2.fg == tty->last_cell.fg &&
2259 	    gc2.bg == tty->last_cell.bg &&
2260 	    gc2.us == tty->last_cell.us)
2261 		return;
2262 
2263 	/*
2264 	 * If no setab, try to use the reverse attribute as a best-effort for a
2265 	 * non-default background. This is a bit of a hack but it doesn't do
2266 	 * any serious harm and makes a couple of applications happier.
2267 	 */
2268 	if (!tty_term_has(tty->term, TTYC_SETAB)) {
2269 		if (gc2.attr & GRID_ATTR_REVERSE) {
2270 			if (gc2.fg != 7 && !COLOUR_DEFAULT(gc2.fg))
2271 				gc2.attr &= ~GRID_ATTR_REVERSE;
2272 		} else {
2273 			if (gc2.bg != 0 && !COLOUR_DEFAULT(gc2.bg))
2274 				gc2.attr |= GRID_ATTR_REVERSE;
2275 		}
2276 	}
2277 
2278 	/* Fix up the colours if necessary. */
2279 	tty_check_fg(tty, palette, &gc2);
2280 	tty_check_bg(tty, palette, &gc2);
2281 	tty_check_us(tty, palette, &gc2);
2282 
2283 	/*
2284 	 * If any bits are being cleared or the underline colour is now default,
2285 	 * reset everything.
2286 	 */
2287 	if ((tc->attr & ~gc2.attr) || (tc->us != gc2.us && gc2.us == 0))
2288 		tty_reset(tty);
2289 
2290 	/*
2291 	 * Set the colours. This may call tty_reset() (so it comes next) and
2292 	 * may add to (NOT remove) the desired attributes.
2293 	 */
2294 	tty_colours(tty, &gc2);
2295 
2296 	/* Filter out attribute bits already set. */
2297 	changed = gc2.attr & ~tc->attr;
2298 	tc->attr = gc2.attr;
2299 
2300 	/* Set the attributes. */
2301 	if (changed & GRID_ATTR_BRIGHT)
2302 		tty_putcode(tty, TTYC_BOLD);
2303 	if (changed & GRID_ATTR_DIM)
2304 		tty_putcode(tty, TTYC_DIM);
2305 	if (changed & GRID_ATTR_ITALICS)
2306 		tty_set_italics(tty);
2307 	if (changed & GRID_ATTR_ALL_UNDERSCORE) {
2308 		if ((changed & GRID_ATTR_UNDERSCORE) ||
2309 		    !tty_term_has(tty->term, TTYC_SMULX))
2310 			tty_putcode(tty, TTYC_SMUL);
2311 		else if (changed & GRID_ATTR_UNDERSCORE_2)
2312 			tty_putcode1(tty, TTYC_SMULX, 2);
2313 		else if (changed & GRID_ATTR_UNDERSCORE_3)
2314 			tty_putcode1(tty, TTYC_SMULX, 3);
2315 		else if (changed & GRID_ATTR_UNDERSCORE_4)
2316 			tty_putcode1(tty, TTYC_SMULX, 4);
2317 		else if (changed & GRID_ATTR_UNDERSCORE_5)
2318 			tty_putcode1(tty, TTYC_SMULX, 5);
2319 	}
2320 	if (changed & GRID_ATTR_BLINK)
2321 		tty_putcode(tty, TTYC_BLINK);
2322 	if (changed & GRID_ATTR_REVERSE) {
2323 		if (tty_term_has(tty->term, TTYC_REV))
2324 			tty_putcode(tty, TTYC_REV);
2325 		else if (tty_term_has(tty->term, TTYC_SMSO))
2326 			tty_putcode(tty, TTYC_SMSO);
2327 	}
2328 	if (changed & GRID_ATTR_HIDDEN)
2329 		tty_putcode(tty, TTYC_INVIS);
2330 	if (changed & GRID_ATTR_STRIKETHROUGH)
2331 		tty_putcode(tty, TTYC_SMXX);
2332 	if (changed & GRID_ATTR_OVERLINE)
2333 		tty_putcode(tty, TTYC_SMOL);
2334 	if ((changed & GRID_ATTR_CHARSET) && tty_acs_needed(tty))
2335 		tty_putcode(tty, TTYC_SMACS);
2336 
2337 	memcpy(&tty->last_cell, &gc2, sizeof tty->last_cell);
2338 }
2339 
2340 static void
2341 tty_colours(struct tty *tty, const struct grid_cell *gc)
2342 {
2343 	struct grid_cell	*tc = &tty->cell;
2344 	int			 have_ax;
2345 
2346 	/* No changes? Nothing is necessary. */
2347 	if (gc->fg == tc->fg && gc->bg == tc->bg && gc->us == tc->us)
2348 		return;
2349 
2350 	/*
2351 	 * Is either the default colour? This is handled specially because the
2352 	 * best solution might be to reset both colours to default, in which
2353 	 * case if only one is default need to fall onward to set the other
2354 	 * colour.
2355 	 */
2356 	if (COLOUR_DEFAULT(gc->fg) || COLOUR_DEFAULT(gc->bg)) {
2357 		/*
2358 		 * If don't have AX but do have op, send sgr0 (op can't
2359 		 * actually be used because it is sometimes the same as sgr0
2360 		 * and sometimes isn't). This resets both colours to default.
2361 		 *
2362 		 * Otherwise, try to set the default colour only as needed.
2363 		 */
2364 		have_ax = tty_term_flag(tty->term, TTYC_AX);
2365 		if (!have_ax && tty_term_has(tty->term, TTYC_OP))
2366 			tty_reset(tty);
2367 		else {
2368 			if (COLOUR_DEFAULT(gc->fg) && !COLOUR_DEFAULT(tc->fg)) {
2369 				if (have_ax)
2370 					tty_puts(tty, "\033[39m");
2371 				else if (tc->fg != 7)
2372 					tty_putcode1(tty, TTYC_SETAF, 7);
2373 				tc->fg = gc->fg;
2374 			}
2375 			if (COLOUR_DEFAULT(gc->bg) && !COLOUR_DEFAULT(tc->bg)) {
2376 				if (have_ax)
2377 					tty_puts(tty, "\033[49m");
2378 				else if (tc->bg != 0)
2379 					tty_putcode1(tty, TTYC_SETAB, 0);
2380 				tc->bg = gc->bg;
2381 			}
2382 		}
2383 	}
2384 
2385 	/* Set the foreground colour. */
2386 	if (!COLOUR_DEFAULT(gc->fg) && gc->fg != tc->fg)
2387 		tty_colours_fg(tty, gc);
2388 
2389 	/*
2390 	 * Set the background colour. This must come after the foreground as
2391 	 * tty_colour_fg() can call tty_reset().
2392 	 */
2393 	if (!COLOUR_DEFAULT(gc->bg) && gc->bg != tc->bg)
2394 		tty_colours_bg(tty, gc);
2395 
2396 	/* Set the underscore color. */
2397 	if (gc->us != tc->us)
2398 		tty_colours_us(tty, gc);
2399 }
2400 
2401 static void
2402 tty_check_fg(struct tty *tty, int *palette, struct grid_cell *gc)
2403 {
2404 	u_char	r, g, b;
2405 	u_int	colours;
2406 	int	c;
2407 
2408 	/*
2409 	 * Perform substitution if this pane has a palette. If the bright
2410 	 * attribute is set, use the bright entry in the palette by changing to
2411 	 * the aixterm colour.
2412 	 */
2413 	if (~gc->flags & GRID_FLAG_NOPALETTE) {
2414 		c = gc->fg;
2415 		if (c < 8 && gc->attr & GRID_ATTR_BRIGHT)
2416 			c += 90;
2417 		if ((c = tty_get_palette(palette, c)) != -1)
2418 			gc->fg = c;
2419 	}
2420 
2421 	/* Is this a 24-bit colour? */
2422 	if (gc->fg & COLOUR_FLAG_RGB) {
2423 		/* Not a 24-bit terminal? Translate to 256-colour palette. */
2424 		if (tty->term->flags & TERM_RGBCOLOURS)
2425 			return;
2426 		colour_split_rgb(gc->fg, &r, &g, &b);
2427 		gc->fg = colour_find_rgb(r, g, b);
2428 	}
2429 
2430 	/* How many colours does this terminal have? */
2431 	if (tty->term->flags & TERM_256COLOURS)
2432 		colours = 256;
2433 	else
2434 		colours = tty_term_number(tty->term, TTYC_COLORS);
2435 
2436 	/* Is this a 256-colour colour? */
2437 	if (gc->fg & COLOUR_FLAG_256) {
2438 		/* And not a 256 colour mode? */
2439 		if (colours < 256) {
2440 			gc->fg = colour_256to16(gc->fg);
2441 			if (gc->fg & 8) {
2442 				gc->fg &= 7;
2443 				if (colours >= 16)
2444 					gc->fg += 90;
2445 			}
2446 		}
2447 		return;
2448 	}
2449 
2450 	/* Is this an aixterm colour? */
2451 	if (gc->fg >= 90 && gc->fg <= 97 && colours < 16) {
2452 		gc->fg -= 90;
2453 		gc->attr |= GRID_ATTR_BRIGHT;
2454 	}
2455 }
2456 
2457 static void
2458 tty_check_bg(struct tty *tty, int *palette, struct grid_cell *gc)
2459 {
2460 	u_char	r, g, b;
2461 	u_int	colours;
2462 	int	c;
2463 
2464 	/* Perform substitution if this pane has a palette. */
2465 	if (~gc->flags & GRID_FLAG_NOPALETTE) {
2466 		if ((c = tty_get_palette(palette, gc->bg)) != -1)
2467 			gc->bg = c;
2468 	}
2469 
2470 	/* Is this a 24-bit colour? */
2471 	if (gc->bg & COLOUR_FLAG_RGB) {
2472 		/* Not a 24-bit terminal? Translate to 256-colour palette. */
2473 		if (tty->term->flags & TERM_RGBCOLOURS)
2474 			return;
2475 		colour_split_rgb(gc->bg, &r, &g, &b);
2476 		gc->bg = colour_find_rgb(r, g, b);
2477 	}
2478 
2479 	/* How many colours does this terminal have? */
2480 	if (tty->term->flags & TERM_256COLOURS)
2481 		colours = 256;
2482 	else
2483 		colours = tty_term_number(tty->term, TTYC_COLORS);
2484 
2485 	/* Is this a 256-colour colour? */
2486 	if (gc->bg & COLOUR_FLAG_256) {
2487 		/*
2488 		 * And not a 256 colour mode? Translate to 16-colour
2489 		 * palette. Bold background doesn't exist portably, so just
2490 		 * discard the bold bit if set.
2491 		 */
2492 		if (colours < 256) {
2493 			gc->bg = colour_256to16(gc->bg);
2494 			if (gc->bg & 8) {
2495 				gc->bg &= 7;
2496 				if (colours >= 16)
2497 					gc->bg += 90;
2498 			}
2499 		}
2500 		return;
2501 	}
2502 
2503 	/* Is this an aixterm colour? */
2504 	if (gc->bg >= 90 && gc->bg <= 97 && colours < 16)
2505 		gc->bg -= 90;
2506 }
2507 
2508 static void
2509 tty_check_us(__unused struct tty *tty, int *palette, struct grid_cell *gc)
2510 {
2511 	int	c;
2512 
2513 	/* Perform substitution if this pane has a palette. */
2514 	if (~gc->flags & GRID_FLAG_NOPALETTE) {
2515 		if ((c = tty_get_palette(palette, gc->us)) != -1)
2516 			gc->us = c;
2517 	}
2518 
2519 	/* Underscore colour is set as RGB so convert a 256 colour to RGB. */
2520 	if (gc->us & COLOUR_FLAG_256)
2521 		gc->us = colour_256toRGB (gc->us);
2522 }
2523 
2524 static void
2525 tty_colours_fg(struct tty *tty, const struct grid_cell *gc)
2526 {
2527 	struct grid_cell	*tc = &tty->cell;
2528 	char			 s[32];
2529 
2530 	/* Is this a 24-bit or 256-colour colour? */
2531 	if (gc->fg & COLOUR_FLAG_RGB || gc->fg & COLOUR_FLAG_256) {
2532 		if (tty_try_colour(tty, gc->fg, "38") == 0)
2533 			goto save;
2534 		/* Should not get here, already converted in tty_check_fg. */
2535 		return;
2536 	}
2537 
2538 	/* Is this an aixterm bright colour? */
2539 	if (gc->fg >= 90 && gc->fg <= 97) {
2540 		if (tty->term->flags & TERM_256COLOURS) {
2541 			xsnprintf(s, sizeof s, "\033[%dm", gc->fg);
2542 			tty_puts(tty, s);
2543 		} else
2544 			tty_putcode1(tty, TTYC_SETAF, gc->fg - 90 + 8);
2545 		goto save;
2546 	}
2547 
2548 	/* Otherwise set the foreground colour. */
2549 	tty_putcode1(tty, TTYC_SETAF, gc->fg);
2550 
2551 save:
2552 	/* Save the new values in the terminal current cell. */
2553 	tc->fg = gc->fg;
2554 }
2555 
2556 static void
2557 tty_colours_bg(struct tty *tty, const struct grid_cell *gc)
2558 {
2559 	struct grid_cell	*tc = &tty->cell;
2560 	char			 s[32];
2561 
2562 	/* Is this a 24-bit or 256-colour colour? */
2563 	if (gc->bg & COLOUR_FLAG_RGB || gc->bg & COLOUR_FLAG_256) {
2564 		if (tty_try_colour(tty, gc->bg, "48") == 0)
2565 			goto save;
2566 		/* Should not get here, already converted in tty_check_bg. */
2567 		return;
2568 	}
2569 
2570 	/* Is this an aixterm bright colour? */
2571 	if (gc->bg >= 90 && gc->bg <= 97) {
2572 		if (tty->term->flags & TERM_256COLOURS) {
2573 			xsnprintf(s, sizeof s, "\033[%dm", gc->bg + 10);
2574 			tty_puts(tty, s);
2575 		} else
2576 			tty_putcode1(tty, TTYC_SETAB, gc->bg - 90 + 8);
2577 		goto save;
2578 	}
2579 
2580 	/* Otherwise set the background colour. */
2581 	tty_putcode1(tty, TTYC_SETAB, gc->bg);
2582 
2583 save:
2584 	/* Save the new values in the terminal current cell. */
2585 	tc->bg = gc->bg;
2586 }
2587 
2588 static void
2589 tty_colours_us(struct tty *tty, const struct grid_cell *gc)
2590 {
2591 	struct grid_cell	*tc = &tty->cell;
2592 	u_int			 c;
2593 	u_char			 r, g, b;
2594 
2595 	/* Clear underline colour. */
2596 	if (gc->us == 0) {
2597 		tty_putcode(tty, TTYC_OL);
2598 		goto save;
2599 	}
2600 
2601 	/* Must be an RGB colour - this should never happen. */
2602 	if (~gc->us & COLOUR_FLAG_RGB)
2603 		return;
2604 
2605 	/*
2606 	 * Setulc and setal follows the ncurses(3) one argument "direct colour"
2607 	 * capability format. Calculate the colour value.
2608 	 */
2609 	colour_split_rgb(gc->us, &r, &g, &b);
2610 	c = (65536 * r) + (256 * g) + b;
2611 
2612 	/*
2613 	 * Write the colour. Only use setal if the RGB flag is set because the
2614 	 * non-RGB version may be wrong.
2615 	 */
2616 	if (tty_term_has(tty->term, TTYC_SETULC))
2617 		tty_putcode1(tty, TTYC_SETULC, c);
2618 	else if (tty_term_has(tty->term, TTYC_SETAL) &&
2619 	    tty_term_has(tty->term, TTYC_RGB))
2620 		tty_putcode1(tty, TTYC_SETAL, c);
2621 
2622 save:
2623 	/* Save the new values in the terminal current cell. */
2624 	tc->us = gc->us;
2625 }
2626 
2627 static int
2628 tty_try_colour(struct tty *tty, int colour, const char *type)
2629 {
2630 	u_char	r, g, b;
2631 
2632 	if (colour & COLOUR_FLAG_256) {
2633 		if (*type == '3' && tty_term_has(tty->term, TTYC_SETAF))
2634 			tty_putcode1(tty, TTYC_SETAF, colour & 0xff);
2635 		else if (tty_term_has(tty->term, TTYC_SETAB))
2636 			tty_putcode1(tty, TTYC_SETAB, colour & 0xff);
2637 		return (0);
2638 	}
2639 
2640 	if (colour & COLOUR_FLAG_RGB) {
2641 		colour_split_rgb(colour & 0xffffff, &r, &g, &b);
2642 		if (*type == '3' && tty_term_has(tty->term, TTYC_SETRGBF))
2643 			tty_putcode3(tty, TTYC_SETRGBF, r, g, b);
2644 		else if (tty_term_has(tty->term, TTYC_SETRGBB))
2645 			tty_putcode3(tty, TTYC_SETRGBB, r, g, b);
2646 		return (0);
2647 	}
2648 
2649 	return (-1);
2650 }
2651 
2652 static void
2653 tty_window_default_style(struct grid_cell *gc, struct window_pane *wp)
2654 {
2655 	memcpy(gc, &grid_default_cell, sizeof *gc);
2656 	gc->fg = wp->fg;
2657 	gc->bg = wp->bg;
2658 }
2659 
2660 void
2661 tty_default_colours(struct grid_cell *gc, struct window_pane *wp)
2662 {
2663 	struct options	*oo = wp->options;
2664 
2665 	memcpy(gc, &grid_default_cell, sizeof *gc);
2666 
2667 	if (wp->flags & PANE_STYLECHANGED) {
2668 		wp->flags &= ~PANE_STYLECHANGED;
2669 
2670 		tty_window_default_style(&wp->cached_active_gc, wp);
2671 		style_add(&wp->cached_active_gc, oo, "window-active-style",
2672 		    NULL);
2673 		tty_window_default_style(&wp->cached_gc, wp);
2674 		style_add(&wp->cached_gc, oo, "window-style", NULL);
2675 	}
2676 
2677 	if (gc->fg == 8) {
2678 		if (wp == wp->window->active && wp->cached_active_gc.fg != 8)
2679 			gc->fg = wp->cached_active_gc.fg;
2680 		else
2681 			gc->fg = wp->cached_gc.fg;
2682 	}
2683 
2684 	if (gc->bg == 8) {
2685 		if (wp == wp->window->active && wp->cached_active_gc.bg != 8)
2686 			gc->bg = wp->cached_active_gc.bg;
2687 		else
2688 			gc->bg = wp->cached_gc.bg;
2689 	}
2690 }
2691 
2692 static void
2693 tty_default_attributes(struct tty *tty, const struct grid_cell *defaults,
2694     int *palette, u_int bg)
2695 {
2696 	struct grid_cell	gc;
2697 
2698 	memcpy(&gc, &grid_default_cell, sizeof gc);
2699 	gc.bg = bg;
2700 	tty_attributes(tty, &gc, defaults, palette);
2701 }
2702