xref: /openbsd-src/usr.bin/tmux/tty.c (revision 25c4e8bd056e974b28f4a0ffd39d76c190a56013)
1 /* $OpenBSD: tty.c,v 1.422 2022/07/06 07:36:36 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 *, int);
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 *, struct colour_palette *,
49     		    struct grid_cell *);
50 static void	tty_check_bg(struct tty *, struct colour_palette *,
51     		    struct grid_cell *);
52 static void	tty_check_us(struct tty *, struct colour_palette *,
53     		    struct grid_cell *);
54 static void	tty_colours_fg(struct tty *, const struct grid_cell *);
55 static void	tty_colours_bg(struct tty *, const struct grid_cell *);
56 static void	tty_colours_us(struct tty *, const struct grid_cell *);
57 
58 static void	tty_region_pane(struct tty *, const struct tty_ctx *, u_int,
59 		    u_int);
60 static void	tty_region(struct tty *, u_int, u_int);
61 static void	tty_margin_pane(struct tty *, const struct tty_ctx *);
62 static void	tty_margin(struct tty *, u_int, u_int);
63 static int	tty_large_region(struct tty *, const struct tty_ctx *);
64 static int	tty_fake_bce(const struct tty *, const struct grid_cell *,
65 		    u_int);
66 static void	tty_redraw_region(struct tty *, const struct tty_ctx *);
67 static void	tty_emulate_repeat(struct tty *, enum tty_code_code,
68 		    enum tty_code_code, u_int);
69 static void	tty_repeat_space(struct tty *, u_int);
70 static void	tty_draw_pane(struct tty *, const struct tty_ctx *, u_int);
71 static void	tty_default_attributes(struct tty *, const struct grid_cell *,
72 		    struct colour_palette *, u_int, struct hyperlinks *);
73 static int	tty_check_overlay(struct tty *, u_int, u_int);
74 static void	tty_check_overlay_range(struct tty *, u_int, u_int, u_int,
75 		    struct overlay_ranges *);
76 
77 #define tty_use_margin(tty) \
78 	(tty->term->flags & TERM_DECSLRM)
79 #define tty_full_width(tty, ctx) \
80 	((ctx)->xoff == 0 && (ctx)->sx >= (tty)->sx)
81 
82 #define TTY_BLOCK_INTERVAL (100000 /* 100 milliseconds */)
83 #define TTY_BLOCK_START(tty) (1 + ((tty)->sx * (tty)->sy) * 8)
84 #define TTY_BLOCK_STOP(tty) (1 + ((tty)->sx * (tty)->sy) / 8)
85 
86 #define TTY_QUERY_TIMEOUT 5
87 
88 void
89 tty_create_log(void)
90 {
91 	char	name[64];
92 
93 	xsnprintf(name, sizeof name, "tmux-out-%ld.log", (long)getpid());
94 
95 	tty_log_fd = open(name, O_WRONLY|O_CREAT|O_TRUNC, 0644);
96 	if (tty_log_fd != -1 && fcntl(tty_log_fd, F_SETFD, FD_CLOEXEC) == -1)
97 		fatal("fcntl failed");
98 }
99 
100 int
101 tty_init(struct tty *tty, struct client *c)
102 {
103 	if (!isatty(c->fd))
104 		return (-1);
105 
106 	memset(tty, 0, sizeof *tty);
107 	tty->client = c;
108 
109 	tty->cstyle = SCREEN_CURSOR_DEFAULT;
110 	tty->ccolour = -1;
111 
112 	if (tcgetattr(c->fd, &tty->tio) != 0)
113 		return (-1);
114 	return (0);
115 }
116 
117 void
118 tty_resize(struct tty *tty)
119 {
120 	struct client	*c = tty->client;
121 	struct winsize	 ws;
122 	u_int		 sx, sy, xpixel, ypixel;
123 
124 	if (ioctl(c->fd, TIOCGWINSZ, &ws) != -1) {
125 		sx = ws.ws_col;
126 		if (sx == 0) {
127 			sx = 80;
128 			xpixel = 0;
129 		} else
130 			xpixel = ws.ws_xpixel / sx;
131 		sy = ws.ws_row;
132 		if (sy == 0) {
133 			sy = 24;
134 			ypixel = 0;
135 		} else
136 			ypixel = ws.ws_ypixel / sy;
137 	} else {
138 		sx = 80;
139 		sy = 24;
140 		xpixel = 0;
141 		ypixel = 0;
142 	}
143 	log_debug("%s: %s now %ux%u (%ux%u)", __func__, c->name, sx, sy,
144 	    xpixel, ypixel);
145 	tty_set_size(tty, sx, sy, xpixel, ypixel);
146 	tty_invalidate(tty);
147 }
148 
149 void
150 tty_set_size(struct tty *tty, u_int sx, u_int sy, u_int xpixel, u_int ypixel)
151 {
152 	tty->sx = sx;
153 	tty->sy = sy;
154 	tty->xpixel = xpixel;
155 	tty->ypixel = ypixel;
156 }
157 
158 static void
159 tty_read_callback(__unused int fd, __unused short events, void *data)
160 {
161 	struct tty	*tty = data;
162 	struct client	*c = tty->client;
163 	const char	*name = c->name;
164 	size_t		 size = EVBUFFER_LENGTH(tty->in);
165 	int		 nread;
166 
167 	nread = evbuffer_read(tty->in, c->fd, -1);
168 	if (nread == 0 || nread == -1) {
169 		if (nread == 0)
170 			log_debug("%s: read closed", name);
171 		else
172 			log_debug("%s: read error: %s", name, strerror(errno));
173 		event_del(&tty->event_in);
174 		server_client_lost(tty->client);
175 		return;
176 	}
177 	log_debug("%s: read %d bytes (already %zu)", name, nread, size);
178 
179 	while (tty_keys_next(tty))
180 		;
181 }
182 
183 static void
184 tty_timer_callback(__unused int fd, __unused short events, void *data)
185 {
186 	struct tty	*tty = data;
187 	struct client	*c = tty->client;
188 	struct timeval	 tv = { .tv_usec = TTY_BLOCK_INTERVAL };
189 
190 	log_debug("%s: %zu discarded", c->name, tty->discarded);
191 
192 	c->flags |= CLIENT_ALLREDRAWFLAGS;
193 	c->discarded += tty->discarded;
194 
195 	if (tty->discarded < TTY_BLOCK_STOP(tty)) {
196 		tty->flags &= ~TTY_BLOCK;
197 		tty_invalidate(tty);
198 		return;
199 	}
200 	tty->discarded = 0;
201 	evtimer_add(&tty->timer, &tv);
202 }
203 
204 static int
205 tty_block_maybe(struct tty *tty)
206 {
207 	struct client	*c = tty->client;
208 	size_t		 size = EVBUFFER_LENGTH(tty->out);
209 	struct timeval	 tv = { .tv_usec = TTY_BLOCK_INTERVAL };
210 
211 	if (size == 0)
212 		tty->flags &= ~TTY_NOBLOCK;
213 	else if (tty->flags & TTY_NOBLOCK)
214 		return (0);
215 
216 	if (size < TTY_BLOCK_START(tty))
217 		return (0);
218 
219 	if (tty->flags & TTY_BLOCK)
220 		return (1);
221 	tty->flags |= TTY_BLOCK;
222 
223 	log_debug("%s: can't keep up, %zu discarded", c->name, size);
224 
225 	evbuffer_drain(tty->out, size);
226 	c->discarded += size;
227 
228 	tty->discarded = 0;
229 	evtimer_add(&tty->timer, &tv);
230 	return (1);
231 }
232 
233 static void
234 tty_write_callback(__unused int fd, __unused short events, void *data)
235 {
236 	struct tty	*tty = data;
237 	struct client	*c = tty->client;
238 	size_t		 size = EVBUFFER_LENGTH(tty->out);
239 	int		 nwrite;
240 
241 	nwrite = evbuffer_write(tty->out, c->fd);
242 	if (nwrite == -1)
243 		return;
244 	log_debug("%s: wrote %d bytes (of %zu)", c->name, nwrite, size);
245 
246 	if (c->redraw > 0) {
247 		if ((size_t)nwrite >= c->redraw)
248 			c->redraw = 0;
249 		else
250 			c->redraw -= nwrite;
251 		log_debug("%s: waiting for redraw, %zu bytes left", c->name,
252 		    c->redraw);
253 	} else if (tty_block_maybe(tty))
254 		return;
255 
256 	if (EVBUFFER_LENGTH(tty->out) != 0)
257 		event_add(&tty->event_out, NULL);
258 }
259 
260 int
261 tty_open(struct tty *tty, char **cause)
262 {
263 	struct client	*c = tty->client;
264 
265 	tty->term = tty_term_create(tty, c->term_name, c->term_caps,
266 	    c->term_ncaps, &c->term_features, cause);
267 	if (tty->term == NULL) {
268 		tty_close(tty);
269 		return (-1);
270 	}
271 	tty->flags |= TTY_OPENED;
272 
273 	tty->flags &= ~(TTY_NOCURSOR|TTY_FREEZE|TTY_BLOCK|TTY_TIMER);
274 
275 	event_set(&tty->event_in, c->fd, EV_PERSIST|EV_READ,
276 	    tty_read_callback, tty);
277 	tty->in = evbuffer_new();
278 	if (tty->in == NULL)
279 		fatal("out of memory");
280 
281 	event_set(&tty->event_out, c->fd, EV_WRITE, tty_write_callback, tty);
282 	tty->out = evbuffer_new();
283 	if (tty->out == NULL)
284 		fatal("out of memory");
285 
286 	evtimer_set(&tty->timer, tty_timer_callback, tty);
287 
288 	tty_start_tty(tty);
289 
290 	tty_keys_build(tty);
291 
292 	return (0);
293 }
294 
295 static void
296 tty_start_timer_callback(__unused int fd, __unused short events, void *data)
297 {
298 	struct tty	*tty = data;
299 	struct client	*c = tty->client;
300 
301 	log_debug("%s: start timer fired", c->name);
302 	if ((tty->flags & (TTY_HAVEDA|TTY_HAVEXDA)) == 0)
303 		tty_update_features(tty);
304 	tty->flags |= (TTY_HAVEDA|TTY_HAVEXDA);
305 }
306 
307 void
308 tty_start_tty(struct tty *tty)
309 {
310 	struct client	*c = tty->client;
311 	struct termios	 tio;
312 	struct timeval	 tv = { .tv_sec = TTY_QUERY_TIMEOUT };
313 
314 	setblocking(c->fd, 0);
315 	event_add(&tty->event_in, NULL);
316 
317 	memcpy(&tio, &tty->tio, sizeof tio);
318 	tio.c_iflag &= ~(IXON|IXOFF|ICRNL|INLCR|IGNCR|IMAXBEL|ISTRIP);
319 	tio.c_iflag |= IGNBRK;
320 	tio.c_oflag &= ~(OPOST|ONLCR|OCRNL|ONLRET);
321 	tio.c_lflag &= ~(IEXTEN|ICANON|ECHO|ECHOE|ECHONL|ECHOCTL|ECHOPRT|
322 	    ECHOKE|ISIG);
323 	tio.c_cc[VMIN] = 1;
324 	tio.c_cc[VTIME] = 0;
325 	if (tcsetattr(c->fd, TCSANOW, &tio) == 0)
326 		tcflush(c->fd, TCOFLUSH);
327 
328 	tty_putcode(tty, TTYC_SMCUP);
329 
330 	tty_putcode(tty, TTYC_SMKX);
331 	tty_putcode(tty, TTYC_CLEAR);
332 
333 	if (tty_acs_needed(tty)) {
334 		log_debug("%s: using capabilities for ACS", c->name);
335 		tty_putcode(tty, TTYC_ENACS);
336 	} else
337 		log_debug("%s: using UTF-8 for ACS", c->name);
338 
339 	tty_putcode(tty, TTYC_CNORM);
340 	if (tty_term_has(tty->term, TTYC_KMOUS)) {
341 		tty_puts(tty, "\033[?1000l\033[?1002l\033[?1003l");
342 		tty_puts(tty, "\033[?1006l\033[?1005l");
343 	}
344 
345 	evtimer_set(&tty->start_timer, tty_start_timer_callback, tty);
346 	evtimer_add(&tty->start_timer, &tv);
347 
348 	tty->flags |= TTY_STARTED;
349 	tty_invalidate(tty);
350 
351 	if (tty->ccolour != -1)
352 		tty_force_cursor_colour(tty, -1);
353 
354 	tty->mouse_drag_flag = 0;
355 	tty->mouse_drag_update = NULL;
356 	tty->mouse_drag_release = NULL;
357 }
358 
359 void
360 tty_send_requests(struct tty *tty)
361 {
362 	if (~tty->flags & TTY_STARTED)
363 		return;
364 
365 	if (tty->term->flags & TERM_VT100LIKE) {
366 		if (~tty->flags & TTY_HAVEDA)
367 			tty_puts(tty, "\033[>c");
368 		if (~tty->flags & TTY_HAVEXDA)
369 			tty_puts(tty, "\033[>q");
370 	} else
371 		tty->flags |= (TTY_HAVEDA|TTY_HAVEXDA);
372 }
373 
374 void
375 tty_stop_tty(struct tty *tty)
376 {
377 	struct client	*c = tty->client;
378 	struct winsize	 ws;
379 
380 	if (!(tty->flags & TTY_STARTED))
381 		return;
382 	tty->flags &= ~TTY_STARTED;
383 
384 	evtimer_del(&tty->start_timer);
385 
386 	event_del(&tty->timer);
387 	tty->flags &= ~TTY_BLOCK;
388 
389 	event_del(&tty->event_in);
390 	event_del(&tty->event_out);
391 
392 	/*
393 	 * Be flexible about error handling and try not kill the server just
394 	 * because the fd is invalid. Things like ssh -t can easily leave us
395 	 * with a dead tty.
396 	 */
397 	if (ioctl(c->fd, TIOCGWINSZ, &ws) == -1)
398 		return;
399 	if (tcsetattr(c->fd, TCSANOW, &tty->tio) == -1)
400 		return;
401 
402 	tty_raw(tty, tty_term_string2(tty->term, TTYC_CSR, 0, ws.ws_row - 1));
403 	if (tty_acs_needed(tty))
404 		tty_raw(tty, tty_term_string(tty->term, TTYC_RMACS));
405 	tty_raw(tty, tty_term_string(tty->term, TTYC_SGR0));
406 	tty_raw(tty, tty_term_string(tty->term, TTYC_RMKX));
407 	tty_raw(tty, tty_term_string(tty->term, TTYC_CLEAR));
408 	if (tty->cstyle != SCREEN_CURSOR_DEFAULT) {
409 		if (tty_term_has(tty->term, TTYC_SE))
410 			tty_raw(tty, tty_term_string(tty->term, TTYC_SE));
411 		else if (tty_term_has(tty->term, TTYC_SS))
412 			tty_raw(tty, tty_term_string1(tty->term, TTYC_SS, 0));
413 	}
414 	if (tty->mode & MODE_BRACKETPASTE)
415 		tty_raw(tty, tty_term_string(tty->term, TTYC_DSBP));
416 	if (tty->ccolour != -1)
417 		tty_raw(tty, tty_term_string(tty->term, TTYC_CR));
418 
419 	tty_raw(tty, tty_term_string(tty->term, TTYC_CNORM));
420 	if (tty_term_has(tty->term, TTYC_KMOUS)) {
421 		tty_raw(tty, "\033[?1000l\033[?1002l\033[?1003l");
422 		tty_raw(tty, "\033[?1006l\033[?1005l");
423 	}
424 
425 	if (tty->term->flags & TERM_VT100LIKE)
426 		tty_raw(tty, "\033[?7727l");
427 	tty_raw(tty, tty_term_string(tty->term, TTYC_DSFCS));
428 	tty_raw(tty, tty_term_string(tty->term, TTYC_DSEKS));
429 
430 	if (tty_use_margin(tty))
431 		tty_raw(tty, tty_term_string(tty->term, TTYC_DSMG));
432 	tty_raw(tty, tty_term_string(tty->term, TTYC_RMCUP));
433 
434 	setblocking(c->fd, 1);
435 }
436 
437 void
438 tty_close(struct tty *tty)
439 {
440 	if (event_initialized(&tty->key_timer))
441 		evtimer_del(&tty->key_timer);
442 	tty_stop_tty(tty);
443 
444 	if (tty->flags & TTY_OPENED) {
445 		evbuffer_free(tty->in);
446 		event_del(&tty->event_in);
447 		evbuffer_free(tty->out);
448 		event_del(&tty->event_out);
449 
450 		tty_term_free(tty->term);
451 		tty_keys_free(tty);
452 
453 		tty->flags &= ~TTY_OPENED;
454 	}
455 }
456 
457 void
458 tty_free(struct tty *tty)
459 {
460 	tty_close(tty);
461 }
462 
463 void
464 tty_update_features(struct tty *tty)
465 {
466 	struct client	*c = tty->client;
467 
468 	if (tty_apply_features(tty->term, c->term_features))
469 		tty_term_apply_overrides(tty->term);
470 
471 	if (tty_use_margin(tty))
472 		tty_putcode(tty, TTYC_ENMG);
473 	if (options_get_number(global_options, "extended-keys"))
474 		tty_puts(tty, tty_term_string(tty->term, TTYC_ENEKS));
475 	if (options_get_number(global_options, "focus-events"))
476 		tty_puts(tty, tty_term_string(tty->term, TTYC_ENFCS));
477 	if (tty->term->flags & TERM_VT100LIKE)
478 		tty_puts(tty, "\033[?7727h");
479 }
480 
481 void
482 tty_raw(struct tty *tty, const char *s)
483 {
484 	struct client	*c = tty->client;
485 	ssize_t		 n, slen;
486 	u_int		 i;
487 
488 	slen = strlen(s);
489 	for (i = 0; i < 5; i++) {
490 		n = write(c->fd, s, slen);
491 		if (n >= 0) {
492 			s += n;
493 			slen -= n;
494 			if (slen == 0)
495 				break;
496 		} else if (n == -1 && errno != EAGAIN)
497 			break;
498 		usleep(100);
499 	}
500 }
501 
502 void
503 tty_putcode(struct tty *tty, enum tty_code_code code)
504 {
505 	tty_puts(tty, tty_term_string(tty->term, code));
506 }
507 
508 void
509 tty_putcode1(struct tty *tty, enum tty_code_code code, int a)
510 {
511 	if (a < 0)
512 		return;
513 	tty_puts(tty, tty_term_string1(tty->term, code, a));
514 }
515 
516 void
517 tty_putcode2(struct tty *tty, enum tty_code_code code, int a, int b)
518 {
519 	if (a < 0 || b < 0)
520 		return;
521 	tty_puts(tty, tty_term_string2(tty->term, code, a, b));
522 }
523 
524 void
525 tty_putcode3(struct tty *tty, enum tty_code_code code, int a, int b, int c)
526 {
527 	if (a < 0 || b < 0 || c < 0)
528 		return;
529 	tty_puts(tty, tty_term_string3(tty->term, code, a, b, c));
530 }
531 
532 void
533 tty_putcode_ptr1(struct tty *tty, enum tty_code_code code, const void *a)
534 {
535 	if (a != NULL)
536 		tty_puts(tty, tty_term_ptr1(tty->term, code, a));
537 }
538 
539 void
540 tty_putcode_ptr2(struct tty *tty, enum tty_code_code code, const void *a,
541     const void *b)
542 {
543 	if (a != NULL && b != NULL)
544 		tty_puts(tty, tty_term_ptr2(tty->term, code, a, b));
545 }
546 
547 static void
548 tty_add(struct tty *tty, const char *buf, size_t len)
549 {
550 	struct client	*c = tty->client;
551 
552 	if (tty->flags & TTY_BLOCK) {
553 		tty->discarded += len;
554 		return;
555 	}
556 
557 	evbuffer_add(tty->out, buf, len);
558 	log_debug("%s: %.*s", c->name, (int)len, buf);
559 	c->written += len;
560 
561 	if (tty_log_fd != -1)
562 		write(tty_log_fd, buf, len);
563 	if (tty->flags & TTY_STARTED)
564 		event_add(&tty->event_out, NULL);
565 }
566 
567 void
568 tty_puts(struct tty *tty, const char *s)
569 {
570 	if (*s != '\0')
571 		tty_add(tty, s, strlen(s));
572 }
573 
574 void
575 tty_putc(struct tty *tty, u_char ch)
576 {
577 	const char	*acs;
578 
579 	if ((tty->term->flags & TERM_NOAM) &&
580 	    ch >= 0x20 && ch != 0x7f &&
581 	    tty->cy == tty->sy - 1 &&
582 	    tty->cx + 1 >= tty->sx)
583 		return;
584 
585 	if (tty->cell.attr & GRID_ATTR_CHARSET) {
586 		acs = tty_acs_get(tty, ch);
587 		if (acs != NULL)
588 			tty_add(tty, acs, strlen(acs));
589 		else
590 			tty_add(tty, &ch, 1);
591 	} else
592 		tty_add(tty, &ch, 1);
593 
594 	if (ch >= 0x20 && ch != 0x7f) {
595 		if (tty->cx >= tty->sx) {
596 			tty->cx = 1;
597 			if (tty->cy != tty->rlower)
598 				tty->cy++;
599 
600 			/*
601 			 * On !am terminals, force the cursor position to where
602 			 * we think it should be after a line wrap - this means
603 			 * it works on sensible terminals as well.
604 			 */
605 			if (tty->term->flags & TERM_NOAM)
606 				tty_putcode2(tty, TTYC_CUP, tty->cy, tty->cx);
607 		} else
608 			tty->cx++;
609 	}
610 }
611 
612 void
613 tty_putn(struct tty *tty, const void *buf, size_t len, u_int width)
614 {
615 	if ((tty->term->flags & TERM_NOAM) &&
616 	    tty->cy == tty->sy - 1 &&
617 	    tty->cx + len >= tty->sx)
618 		len = tty->sx - tty->cx - 1;
619 
620 	tty_add(tty, buf, len);
621 	if (tty->cx + width > tty->sx) {
622 		tty->cx = (tty->cx + width) - tty->sx;
623 		if (tty->cx <= tty->sx)
624 			tty->cy++;
625 		else
626 			tty->cx = tty->cy = UINT_MAX;
627 	} else
628 		tty->cx += width;
629 }
630 
631 static void
632 tty_set_italics(struct tty *tty)
633 {
634 	const char	*s;
635 
636 	if (tty_term_has(tty->term, TTYC_SITM)) {
637 		s = options_get_string(global_options, "default-terminal");
638 		if (strcmp(s, "screen") != 0 && strncmp(s, "screen-", 7) != 0) {
639 			tty_putcode(tty, TTYC_SITM);
640 			return;
641 		}
642 	}
643 	tty_putcode(tty, TTYC_SMSO);
644 }
645 
646 void
647 tty_set_title(struct tty *tty, const char *title)
648 {
649 	if (!tty_term_has(tty->term, TTYC_TSL) ||
650 	    !tty_term_has(tty->term, TTYC_FSL))
651 		return;
652 
653 	tty_putcode(tty, TTYC_TSL);
654 	tty_puts(tty, title);
655 	tty_putcode(tty, TTYC_FSL);
656 }
657 
658 void
659 tty_set_path(struct tty *tty, const char *title)
660 {
661 	if (!tty_term_has(tty->term, TTYC_SWD) ||
662 	    !tty_term_has(tty->term, TTYC_FSL))
663 		return;
664 
665 	tty_putcode(tty, TTYC_SWD);
666 	tty_puts(tty, title);
667 	tty_putcode(tty, TTYC_FSL);
668 }
669 
670 static void
671 tty_force_cursor_colour(struct tty *tty, int c)
672 {
673 	u_char	r, g, b;
674 	char	s[13];
675 
676 	if (c != -1)
677 		c = colour_force_rgb(c);
678 	if (c == tty->ccolour)
679 		return;
680 	if (c == -1)
681 		tty_putcode(tty, TTYC_CR);
682 	else {
683 		colour_split_rgb(c, &r, &g, &b);
684 		xsnprintf(s, sizeof s, "rgb:%02hhx/%02hhx/%02hhx", r, g, b);
685 		tty_putcode_ptr1(tty, TTYC_CS, s);
686 	}
687 	tty->ccolour = c;
688 }
689 
690 static int
691 tty_update_cursor(struct tty *tty, int mode, struct screen *s)
692 {
693 	enum screen_cursor_style	cstyle;
694 	int				ccolour, changed, cmode = mode;
695 
696 	/* Set cursor colour if changed. */
697 	if (s != NULL) {
698 		ccolour = s->ccolour;
699 		if (s->ccolour == -1)
700 			ccolour = s->default_ccolour;
701 		tty_force_cursor_colour(tty, ccolour);
702 	}
703 
704 	/* If cursor is off, set as invisible. */
705 	if (~cmode & MODE_CURSOR) {
706 		if (tty->mode & MODE_CURSOR)
707 			tty_putcode(tty, TTYC_CIVIS);
708 		return (cmode);
709 	}
710 
711 	/* Check if blinking or very visible flag changed or style changed. */
712 	if (s == NULL)
713 		cstyle = tty->cstyle;
714 	else {
715 		cstyle = s->cstyle;
716 		if (cstyle == SCREEN_CURSOR_DEFAULT) {
717 			if (~cmode & MODE_CURSOR_BLINKING_SET) {
718 				if (s->default_mode & MODE_CURSOR_BLINKING)
719 					cmode |= MODE_CURSOR_BLINKING;
720 				else
721 					cmode &= ~MODE_CURSOR_BLINKING;
722 			}
723 			cstyle = s->default_cstyle;
724 		}
725 	}
726 
727 	/* If nothing changed, do nothing. */
728 	changed = cmode ^ tty->mode;
729 	if ((changed & CURSOR_MODES) == 0 && cstyle == tty->cstyle)
730 		return (cmode);
731 
732 	/*
733 	 * Set cursor style. If an explicit style has been set with DECSCUSR,
734 	 * set it if supported, otherwise send cvvis for blinking styles.
735 	 *
736 	 * If no style, has been set (SCREEN_CURSOR_DEFAULT), then send cvvis
737 	 * if either the blinking or very visible flags are set.
738 	 */
739 	tty_putcode(tty, TTYC_CNORM);
740 	switch (cstyle) {
741 	case SCREEN_CURSOR_DEFAULT:
742 		if (tty->cstyle != SCREEN_CURSOR_DEFAULT) {
743 			if (tty_term_has(tty->term, TTYC_SE))
744 				tty_putcode(tty, TTYC_SE);
745 			else
746 				tty_putcode1(tty, TTYC_SS, 0);
747 		}
748 		if (cmode & (MODE_CURSOR_BLINKING|MODE_CURSOR_VERY_VISIBLE))
749 			tty_putcode(tty, TTYC_CVVIS);
750 		break;
751 	case SCREEN_CURSOR_BLOCK:
752 		if (tty_term_has(tty->term, TTYC_SS)) {
753 			if (cmode & MODE_CURSOR_BLINKING)
754 				tty_putcode1(tty, TTYC_SS, 1);
755 			else
756 				tty_putcode1(tty, TTYC_SS, 2);
757 		} else if (cmode & MODE_CURSOR_BLINKING)
758 			tty_putcode(tty, TTYC_CVVIS);
759 		break;
760 	case SCREEN_CURSOR_UNDERLINE:
761 		if (tty_term_has(tty->term, TTYC_SS)) {
762 			if (cmode & MODE_CURSOR_BLINKING)
763 				tty_putcode1(tty, TTYC_SS, 3);
764 			else
765 				tty_putcode1(tty, TTYC_SS, 4);
766 		} else if (cmode & MODE_CURSOR_BLINKING)
767 			tty_putcode(tty, TTYC_CVVIS);
768 		break;
769 	case SCREEN_CURSOR_BAR:
770 		if (tty_term_has(tty->term, TTYC_SS)) {
771 			if (cmode & MODE_CURSOR_BLINKING)
772 				tty_putcode1(tty, TTYC_SS, 5);
773 			else
774 				tty_putcode1(tty, TTYC_SS, 6);
775 		} else if (cmode & MODE_CURSOR_BLINKING)
776 			tty_putcode(tty, TTYC_CVVIS);
777 		break;
778 	}
779 	tty->cstyle = cstyle;
780 	return (cmode);
781  }
782 
783 void
784 tty_update_mode(struct tty *tty, int mode, struct screen *s)
785 {
786 	struct tty_term	*term = tty->term;
787 	struct client	*c = tty->client;
788 	int		 changed;
789 
790 	if (tty->flags & TTY_NOCURSOR)
791 		mode &= ~MODE_CURSOR;
792 
793 	if (tty_update_cursor(tty, mode, s) & MODE_CURSOR_BLINKING)
794 		mode |= MODE_CURSOR_BLINKING;
795 	else
796 		mode &= ~MODE_CURSOR_BLINKING;
797 
798 	changed = mode ^ tty->mode;
799 	if (log_get_level() != 0 && changed != 0) {
800 		log_debug("%s: current mode %s", c->name,
801 		    screen_mode_to_string(tty->mode));
802 		log_debug("%s: setting mode %s", c->name,
803 		    screen_mode_to_string(mode));
804 	}
805 
806 	if ((changed & ALL_MOUSE_MODES) && tty_term_has(term, TTYC_KMOUS)) {
807 		/*
808 		 * If the mouse modes have changed, clear then all and apply
809 		 * again. There are differences in how terminals track the
810 		 * various bits.
811 		 */
812 		tty_puts(tty, "\033[?1006l\033[?1000l\033[?1002l\033[?1003l");
813 		if (mode & ALL_MOUSE_MODES)
814 			tty_puts(tty, "\033[?1006h");
815 		if (mode & MODE_MOUSE_ALL)
816 			tty_puts(tty, "\033[?1000h\033[?1002h\033[?1003h");
817 		else if (mode & MODE_MOUSE_BUTTON)
818 			tty_puts(tty, "\033[?1000h\033[?1002h");
819 		else if (mode & MODE_MOUSE_STANDARD)
820 			tty_puts(tty, "\033[?1000h");
821 	}
822 	if (changed & MODE_BRACKETPASTE) {
823 		if (mode & MODE_BRACKETPASTE)
824 			tty_putcode(tty, TTYC_ENBP);
825 		else
826 			tty_putcode(tty, TTYC_DSBP);
827 	}
828 	tty->mode = mode;
829 }
830 
831 static void
832 tty_emulate_repeat(struct tty *tty, enum tty_code_code code,
833     enum tty_code_code code1, u_int n)
834 {
835 	if (tty_term_has(tty->term, code))
836 		tty_putcode1(tty, code, n);
837 	else {
838 		while (n-- > 0)
839 			tty_putcode(tty, code1);
840 	}
841 }
842 
843 static void
844 tty_repeat_space(struct tty *tty, u_int n)
845 {
846 	static char s[500];
847 
848 	if (*s != ' ')
849 		memset(s, ' ', sizeof s);
850 
851 	while (n > sizeof s) {
852 		tty_putn(tty, s, sizeof s, sizeof s);
853 		n -= sizeof s;
854 	}
855 	if (n != 0)
856 		tty_putn(tty, s, n, n);
857 }
858 
859 /* Is this window bigger than the terminal? */
860 int
861 tty_window_bigger(struct tty *tty)
862 {
863 	struct client	*c = tty->client;
864 	struct window	*w = c->session->curw->window;
865 
866 	return (tty->sx < w->sx || tty->sy - status_line_size(c) < w->sy);
867 }
868 
869 /* What offset should this window be drawn at? */
870 int
871 tty_window_offset(struct tty *tty, u_int *ox, u_int *oy, u_int *sx, u_int *sy)
872 {
873 	*ox = tty->oox;
874 	*oy = tty->ooy;
875 	*sx = tty->osx;
876 	*sy = tty->osy;
877 
878 	return (tty->oflag);
879 }
880 
881 /* What offset should this window be drawn at? */
882 static int
883 tty_window_offset1(struct tty *tty, u_int *ox, u_int *oy, u_int *sx, u_int *sy)
884 {
885 	struct client		*c = tty->client;
886 	struct window		*w = c->session->curw->window;
887 	struct window_pane	*wp = server_client_get_pane(c);
888 	u_int			 cx, cy, lines;
889 
890 	lines = status_line_size(c);
891 
892 	if (tty->sx >= w->sx && tty->sy - lines >= w->sy) {
893 		*ox = 0;
894 		*oy = 0;
895 		*sx = w->sx;
896 		*sy = w->sy;
897 
898 		c->pan_window = NULL;
899 		return (0);
900 	}
901 
902 	*sx = tty->sx;
903 	*sy = tty->sy - lines;
904 
905 	if (c->pan_window == w) {
906 		if (*sx >= w->sx)
907 			c->pan_ox = 0;
908 		else if (c->pan_ox + *sx > w->sx)
909 			c->pan_ox = w->sx - *sx;
910 		*ox = c->pan_ox;
911 		if (*sy >= w->sy)
912 			c->pan_oy = 0;
913 		else if (c->pan_oy + *sy > w->sy)
914 			c->pan_oy = w->sy - *sy;
915 		*oy = c->pan_oy;
916 		return (1);
917 	}
918 
919 	if (~wp->screen->mode & MODE_CURSOR) {
920 		*ox = 0;
921 		*oy = 0;
922 	} else {
923 		cx = wp->xoff + wp->screen->cx;
924 		cy = wp->yoff + wp->screen->cy;
925 
926 		if (cx < *sx)
927 			*ox = 0;
928 		else if (cx > w->sx - *sx)
929 			*ox = w->sx - *sx;
930 		else
931 			*ox = cx - *sx / 2;
932 
933 		if (cy < *sy)
934 			*oy = 0;
935 		else if (cy > w->sy - *sy)
936 			*oy = w->sy - *sy;
937 		else
938 			*oy = cy - *sy / 2;
939 	}
940 
941 	c->pan_window = NULL;
942 	return (1);
943 }
944 
945 /* Update stored offsets for a window and redraw if necessary. */
946 void
947 tty_update_window_offset(struct window *w)
948 {
949 	struct client	*c;
950 
951 	TAILQ_FOREACH(c, &clients, entry) {
952 		if (c->session != NULL &&
953 		    c->session->curw != NULL &&
954 		    c->session->curw->window == w)
955 			tty_update_client_offset(c);
956 	}
957 }
958 
959 /* Update stored offsets for a client and redraw if necessary. */
960 void
961 tty_update_client_offset(struct client *c)
962 {
963 	u_int	ox, oy, sx, sy;
964 
965 	if (~c->flags & CLIENT_TERMINAL)
966 		return;
967 
968 	c->tty.oflag = tty_window_offset1(&c->tty, &ox, &oy, &sx, &sy);
969 	if (ox == c->tty.oox &&
970 	    oy == c->tty.ooy &&
971 	    sx == c->tty.osx &&
972 	    sy == c->tty.osy)
973 		return;
974 
975 	log_debug ("%s: %s offset has changed (%u,%u %ux%u -> %u,%u %ux%u)",
976 	    __func__, c->name, c->tty.oox, c->tty.ooy, c->tty.osx, c->tty.osy,
977 	    ox, oy, sx, sy);
978 
979 	c->tty.oox = ox;
980 	c->tty.ooy = oy;
981 	c->tty.osx = sx;
982 	c->tty.osy = sy;
983 
984 	c->flags |= (CLIENT_REDRAWWINDOW|CLIENT_REDRAWSTATUS);
985 }
986 
987 /*
988  * Is the region large enough to be worth redrawing once later rather than
989  * probably several times now? Currently yes if it is more than 50% of the
990  * pane.
991  */
992 static int
993 tty_large_region(__unused struct tty *tty, const struct tty_ctx *ctx)
994 {
995 	return (ctx->orlower - ctx->orupper >= ctx->sy / 2);
996 }
997 
998 /*
999  * Return if BCE is needed but the terminal doesn't have it - it'll need to be
1000  * emulated.
1001  */
1002 static int
1003 tty_fake_bce(const struct tty *tty, const struct grid_cell *gc, u_int bg)
1004 {
1005 	if (tty_term_flag(tty->term, TTYC_BCE))
1006 		return (0);
1007 	if (!COLOUR_DEFAULT(bg) || !COLOUR_DEFAULT(gc->bg))
1008 		return (1);
1009 	return (0);
1010 }
1011 
1012 /*
1013  * Redraw scroll region using data from screen (already updated). Used when
1014  * CSR not supported, or window is a pane that doesn't take up the full
1015  * width of the terminal.
1016  */
1017 static void
1018 tty_redraw_region(struct tty *tty, const struct tty_ctx *ctx)
1019 {
1020 	struct client		*c = tty->client;
1021 	u_int			 i;
1022 
1023 	/*
1024 	 * If region is large, schedule a redraw. In most cases this is likely
1025 	 * to be followed by some more scrolling.
1026 	 */
1027 	if (tty_large_region(tty, ctx)) {
1028 		log_debug("%s: %s large redraw", __func__, c->name);
1029 		ctx->redraw_cb(ctx);
1030 		return;
1031 	}
1032 
1033 	for (i = ctx->orupper; i <= ctx->orlower; i++)
1034 		tty_draw_pane(tty, ctx, i);
1035 }
1036 
1037 /* Is this position visible in the pane? */
1038 static int
1039 tty_is_visible(__unused struct tty *tty, const struct tty_ctx *ctx, u_int px,
1040     u_int py, u_int nx, u_int ny)
1041 {
1042 	u_int	xoff = ctx->rxoff + px, yoff = ctx->ryoff + py;
1043 
1044 	if (!ctx->bigger)
1045 		return (1);
1046 
1047 	if (xoff + nx <= ctx->wox || xoff >= ctx->wox + ctx->wsx ||
1048 	    yoff + ny <= ctx->woy || yoff >= ctx->woy + ctx->wsy)
1049 		return (0);
1050 	return (1);
1051 }
1052 
1053 /* Clamp line position to visible part of pane. */
1054 static int
1055 tty_clamp_line(struct tty *tty, const struct tty_ctx *ctx, u_int px, u_int py,
1056     u_int nx, u_int *i, u_int *x, u_int *rx, u_int *ry)
1057 {
1058 	u_int	xoff = ctx->rxoff + px;
1059 
1060 	if (!tty_is_visible(tty, ctx, px, py, nx, 1))
1061 		return (0);
1062 	*ry = ctx->yoff + py - ctx->woy;
1063 
1064 	if (xoff >= ctx->wox && xoff + nx <= ctx->wox + ctx->wsx) {
1065 		/* All visible. */
1066 		*i = 0;
1067 		*x = ctx->xoff + px - ctx->wox;
1068 		*rx = nx;
1069 	} else if (xoff < ctx->wox && xoff + nx > ctx->wox + ctx->wsx) {
1070 		/* Both left and right not visible. */
1071 		*i = ctx->wox;
1072 		*x = 0;
1073 		*rx = ctx->wsx;
1074 	} else if (xoff < ctx->wox) {
1075 		/* Left not visible. */
1076 		*i = ctx->wox - (ctx->xoff + px);
1077 		*x = 0;
1078 		*rx = nx - *i;
1079 	} else {
1080 		/* Right not visible. */
1081 		*i = 0;
1082 		*x = (ctx->xoff + px) - ctx->wox;
1083 		*rx = ctx->wsx - *x;
1084 	}
1085 	if (*rx > nx)
1086 		fatalx("%s: x too big, %u > %u", __func__, *rx, nx);
1087 
1088 	return (1);
1089 }
1090 
1091 /* Clear a line. */
1092 static void
1093 tty_clear_line(struct tty *tty, const struct grid_cell *defaults, u_int py,
1094     u_int px, u_int nx, u_int bg)
1095 {
1096 	struct client		*c = tty->client;
1097 	struct overlay_ranges	 r;
1098 	u_int			 i;
1099 
1100 	log_debug("%s: %s, %u at %u,%u", __func__, c->name, nx, px, py);
1101 
1102 	/* Nothing to clear. */
1103 	if (nx == 0)
1104 		return;
1105 
1106 	/* If genuine BCE is available, can try escape sequences. */
1107 	if (c->overlay_check == NULL && !tty_fake_bce(tty, defaults, bg)) {
1108 		/* Off the end of the line, use EL if available. */
1109 		if (px + nx >= tty->sx && tty_term_has(tty->term, TTYC_EL)) {
1110 			tty_cursor(tty, px, py);
1111 			tty_putcode(tty, TTYC_EL);
1112 			return;
1113 		}
1114 
1115 		/* At the start of the line. Use EL1. */
1116 		if (px == 0 && tty_term_has(tty->term, TTYC_EL1)) {
1117 			tty_cursor(tty, px + nx - 1, py);
1118 			tty_putcode(tty, TTYC_EL1);
1119 			return;
1120 		}
1121 
1122 		/* Section of line. Use ECH if possible. */
1123 		if (tty_term_has(tty->term, TTYC_ECH)) {
1124 			tty_cursor(tty, px, py);
1125 			tty_putcode1(tty, TTYC_ECH, nx);
1126 			return;
1127 		}
1128 	}
1129 
1130 	/*
1131 	 * Couldn't use an escape sequence, use spaces. Clear only the visible
1132 	 * bit if there is an overlay.
1133 	 */
1134 	tty_check_overlay_range(tty, px, py, nx, &r);
1135 	for (i = 0; i < OVERLAY_MAX_RANGES; i++) {
1136 		if (r.nx[i] == 0)
1137 			continue;
1138 		tty_cursor(tty, r.px[i], py);
1139 		tty_repeat_space(tty, r.nx[i]);
1140 	}
1141 }
1142 
1143 /* Clear a line, adjusting to visible part of pane. */
1144 static void
1145 tty_clear_pane_line(struct tty *tty, const struct tty_ctx *ctx, u_int py,
1146     u_int px, u_int nx, u_int bg)
1147 {
1148 	struct client	*c = tty->client;
1149 	u_int		 i, x, rx, ry;
1150 
1151 	log_debug("%s: %s, %u at %u,%u", __func__, c->name, nx, px, py);
1152 
1153 	if (tty_clamp_line(tty, ctx, px, py, nx, &i, &x, &rx, &ry))
1154 		tty_clear_line(tty, &ctx->defaults, ry, x, rx, bg);
1155 }
1156 
1157 /* Clamp area position to visible part of pane. */
1158 static int
1159 tty_clamp_area(struct tty *tty, const struct tty_ctx *ctx, u_int px, u_int py,
1160     u_int nx, u_int ny, u_int *i, u_int *j, u_int *x, u_int *y, u_int *rx,
1161     u_int *ry)
1162 {
1163 	u_int	xoff = ctx->rxoff + px, yoff = ctx->ryoff + py;
1164 
1165 	if (!tty_is_visible(tty, ctx, px, py, nx, ny))
1166 		return (0);
1167 
1168 	if (xoff >= ctx->wox && xoff + nx <= ctx->wox + ctx->wsx) {
1169 		/* All visible. */
1170 		*i = 0;
1171 		*x = ctx->xoff + px - ctx->wox;
1172 		*rx = nx;
1173 	} else if (xoff < ctx->wox && xoff + nx > ctx->wox + ctx->wsx) {
1174 		/* Both left and right not visible. */
1175 		*i = ctx->wox;
1176 		*x = 0;
1177 		*rx = ctx->wsx;
1178 	} else if (xoff < ctx->wox) {
1179 		/* Left not visible. */
1180 		*i = ctx->wox - (ctx->xoff + px);
1181 		*x = 0;
1182 		*rx = nx - *i;
1183 	} else {
1184 		/* Right not visible. */
1185 		*i = 0;
1186 		*x = (ctx->xoff + px) - ctx->wox;
1187 		*rx = ctx->wsx - *x;
1188 	}
1189 	if (*rx > nx)
1190 		fatalx("%s: x too big, %u > %u", __func__, *rx, nx);
1191 
1192 	if (yoff >= ctx->woy && yoff + ny <= ctx->woy + ctx->wsy) {
1193 		/* All visible. */
1194 		*j = 0;
1195 		*y = ctx->yoff + py - ctx->woy;
1196 		*ry = ny;
1197 	} else if (yoff < ctx->woy && yoff + ny > ctx->woy + ctx->wsy) {
1198 		/* Both top and bottom not visible. */
1199 		*j = ctx->woy;
1200 		*y = 0;
1201 		*ry = ctx->wsy;
1202 	} else if (yoff < ctx->woy) {
1203 		/* Top not visible. */
1204 		*j = ctx->woy - (ctx->yoff + py);
1205 		*y = 0;
1206 		*ry = ny - *j;
1207 	} else {
1208 		/* Bottom not visible. */
1209 		*j = 0;
1210 		*y = (ctx->yoff + py) - ctx->woy;
1211 		*ry = ctx->wsy - *y;
1212 	}
1213 	if (*ry > ny)
1214 		fatalx("%s: y too big, %u > %u", __func__, *ry, ny);
1215 
1216 	return (1);
1217 }
1218 
1219 /* Clear an area, adjusting to visible part of pane. */
1220 static void
1221 tty_clear_area(struct tty *tty, const struct grid_cell *defaults, u_int py,
1222     u_int ny, u_int px, u_int nx, u_int bg)
1223 {
1224 	struct client	*c = tty->client;
1225 	u_int		 yy;
1226 	char		 tmp[64];
1227 
1228 	log_debug("%s: %s, %u,%u at %u,%u", __func__, c->name, nx, ny, px, py);
1229 
1230 	/* Nothing to clear. */
1231 	if (nx == 0 || ny == 0)
1232 		return;
1233 
1234 	/* If genuine BCE is available, can try escape sequences. */
1235 	if (c->overlay_check == NULL && !tty_fake_bce(tty, defaults, bg)) {
1236 		/* Use ED if clearing off the bottom of the terminal. */
1237 		if (px == 0 &&
1238 		    px + nx >= tty->sx &&
1239 		    py + ny >= tty->sy &&
1240 		    tty_term_has(tty->term, TTYC_ED)) {
1241 			tty_cursor(tty, 0, py);
1242 			tty_putcode(tty, TTYC_ED);
1243 			return;
1244 		}
1245 
1246 		/*
1247 		 * On VT420 compatible terminals we can use DECFRA if the
1248 		 * background colour isn't default (because it doesn't work
1249 		 * after SGR 0).
1250 		 */
1251 		if ((tty->term->flags & TERM_DECFRA) && !COLOUR_DEFAULT(bg)) {
1252 			xsnprintf(tmp, sizeof tmp, "\033[32;%u;%u;%u;%u$x",
1253 			    py + 1, px + 1, py + ny, px + nx);
1254 			tty_puts(tty, tmp);
1255 			return;
1256 		}
1257 
1258 		/* Full lines can be scrolled away to clear them. */
1259 		if (px == 0 &&
1260 		    px + nx >= tty->sx &&
1261 		    ny > 2 &&
1262 		    tty_term_has(tty->term, TTYC_CSR) &&
1263 		    tty_term_has(tty->term, TTYC_INDN)) {
1264 			tty_region(tty, py, py + ny - 1);
1265 			tty_margin_off(tty);
1266 			tty_putcode1(tty, TTYC_INDN, ny);
1267 			return;
1268 		}
1269 
1270 		/*
1271 		 * If margins are supported, can just scroll the area off to
1272 		 * clear it.
1273 		 */
1274 		if (nx > 2 &&
1275 		    ny > 2 &&
1276 		    tty_term_has(tty->term, TTYC_CSR) &&
1277 		    tty_use_margin(tty) &&
1278 		    tty_term_has(tty->term, TTYC_INDN)) {
1279 			tty_region(tty, py, py + ny - 1);
1280 			tty_margin(tty, px, px + nx - 1);
1281 			tty_putcode1(tty, TTYC_INDN, ny);
1282 			return;
1283 		}
1284 	}
1285 
1286 	/* Couldn't use an escape sequence, loop over the lines. */
1287 	for (yy = py; yy < py + ny; yy++)
1288 		tty_clear_line(tty, defaults, yy, px, nx, bg);
1289 }
1290 
1291 /* Clear an area in a pane. */
1292 static void
1293 tty_clear_pane_area(struct tty *tty, const struct tty_ctx *ctx, u_int py,
1294     u_int ny, u_int px, u_int nx, u_int bg)
1295 {
1296 	u_int	i, j, x, y, rx, ry;
1297 
1298 	if (tty_clamp_area(tty, ctx, px, py, nx, ny, &i, &j, &x, &y, &rx, &ry))
1299 		tty_clear_area(tty, &ctx->defaults, y, ry, x, rx, bg);
1300 }
1301 
1302 static void
1303 tty_draw_pane(struct tty *tty, const struct tty_ctx *ctx, u_int py)
1304 {
1305 	struct screen	*s = ctx->s;
1306 	u_int		 nx = ctx->sx, i, x, rx, ry;
1307 
1308 	log_debug("%s: %s %u %d", __func__, tty->client->name, py, ctx->bigger);
1309 
1310 	if (!ctx->bigger) {
1311 		tty_draw_line(tty, s, 0, py, nx, ctx->xoff, ctx->yoff + py,
1312 		    &ctx->defaults, ctx->palette);
1313 		return;
1314 	}
1315 	if (tty_clamp_line(tty, ctx, 0, py, nx, &i, &x, &rx, &ry)) {
1316 		tty_draw_line(tty, s, i, py, rx, x, ry, &ctx->defaults,
1317 		    ctx->palette);
1318 	}
1319 }
1320 
1321 static const struct grid_cell *
1322 tty_check_codeset(struct tty *tty, const struct grid_cell *gc)
1323 {
1324 	static struct grid_cell	new;
1325 	int			c;
1326 
1327 	/* Characters less than 0x7f are always fine, no matter what. */
1328 	if (gc->data.size == 1 && *gc->data.data < 0x7f)
1329 		return (gc);
1330 
1331 	/* UTF-8 terminal and a UTF-8 character - fine. */
1332 	if (tty->client->flags & CLIENT_UTF8)
1333 		return (gc);
1334 	memcpy(&new, gc, sizeof new);
1335 
1336 	/* See if this can be mapped to an ACS character. */
1337 	c = tty_acs_reverse_get(tty, gc->data.data, gc->data.size);
1338 	if (c != -1) {
1339 		utf8_set(&new.data, c);
1340 		new.attr |= GRID_ATTR_CHARSET;
1341 		return (&new);
1342 	}
1343 
1344 	/* Replace by the right number of underscores. */
1345 	new.data.size = gc->data.width;
1346 	if (new.data.size > UTF8_SIZE)
1347 		new.data.size = UTF8_SIZE;
1348 	memset(new.data.data, '_', new.data.size);
1349 	return (&new);
1350 }
1351 
1352 /*
1353  * Check if a single character is obstructed by the overlay and return a
1354  * boolean.
1355  */
1356 static int
1357 tty_check_overlay(struct tty *tty, u_int px, u_int py)
1358 {
1359 	struct overlay_ranges	r;
1360 
1361 	/*
1362 	 * A unit width range will always return nx[2] == 0 from a check, even
1363 	 * with multiple overlays, so it's sufficient to check just the first
1364 	 * two entries.
1365 	 */
1366 	tty_check_overlay_range(tty, px, py, 1, &r);
1367 	if (r.nx[0] + r.nx[1] == 0)
1368 		return (0);
1369 	return (1);
1370 }
1371 
1372 /* Return parts of the input range which are visible. */
1373 static void
1374 tty_check_overlay_range(struct tty *tty, u_int px, u_int py, u_int nx,
1375     struct overlay_ranges *r)
1376 {
1377 	struct client	*c = tty->client;
1378 
1379 	if (c->overlay_check == NULL) {
1380 		r->px[0] = px;
1381 		r->nx[0] = nx;
1382 		r->px[1] = 0;
1383 		r->nx[1] = 0;
1384 		r->px[2] = 0;
1385 		r->nx[2] = 0;
1386 		return;
1387 	}
1388 
1389 	c->overlay_check(c, c->overlay_data, px, py, nx, r);
1390 }
1391 
1392 void
1393 tty_draw_line(struct tty *tty, struct screen *s, u_int px, u_int py, u_int nx,
1394     u_int atx, u_int aty, const struct grid_cell *defaults,
1395     struct colour_palette *palette)
1396 {
1397 	struct grid		*gd = s->grid;
1398 	struct grid_cell	 gc, last;
1399 	const struct grid_cell	*gcp;
1400 	struct grid_line	*gl;
1401 	struct client		*c = tty->client;
1402 	struct overlay_ranges	 r;
1403 	u_int			 i, j, ux, sx, width, hidden, eux, nxx;
1404 	u_int			 cellsize;
1405 	int			 flags, cleared = 0, wrapped = 0;
1406 	char			 buf[512];
1407 	size_t			 len;
1408 
1409 	log_debug("%s: px=%u py=%u nx=%u atx=%u aty=%u", __func__,
1410 	    px, py, nx, atx, aty);
1411 	log_debug("%s: defaults: fg=%d, bg=%d", __func__, defaults->fg,
1412 	    defaults->bg);
1413 
1414 	/*
1415 	 * py is the line in the screen to draw.
1416 	 * px is the start x and nx is the width to draw.
1417 	 * atx,aty is the line on the terminal to draw it.
1418 	 */
1419 
1420 	flags = (tty->flags & TTY_NOCURSOR);
1421 	tty->flags |= TTY_NOCURSOR;
1422 	tty_update_mode(tty, tty->mode, s);
1423 
1424 	tty_region_off(tty);
1425 	tty_margin_off(tty);
1426 
1427 	/*
1428 	 * Clamp the width to cellsize - note this is not cellused, because
1429 	 * there may be empty background cells after it (from BCE).
1430 	 */
1431 	sx = screen_size_x(s);
1432 	if (nx > sx)
1433 		nx = sx;
1434 	cellsize = grid_get_line(gd, gd->hsize + py)->cellsize;
1435 	if (sx > cellsize)
1436 		sx = cellsize;
1437 	if (sx > tty->sx)
1438 		sx = tty->sx;
1439 	if (sx > nx)
1440 		sx = nx;
1441 	ux = 0;
1442 
1443 	if (py == 0)
1444 		gl = NULL;
1445 	else
1446 		gl = grid_get_line(gd, gd->hsize + py - 1);
1447 	if (gl == NULL ||
1448 	    (~gl->flags & GRID_LINE_WRAPPED) ||
1449 	    atx != 0 ||
1450 	    tty->cx < tty->sx ||
1451 	    nx < tty->sx) {
1452 		if (nx < tty->sx &&
1453 		    atx == 0 &&
1454 		    px + sx != nx &&
1455 		    tty_term_has(tty->term, TTYC_EL1) &&
1456 		    !tty_fake_bce(tty, defaults, 8) &&
1457 		    c->overlay_check == NULL) {
1458 			tty_default_attributes(tty, defaults, palette, 8,
1459 			    s->hyperlinks);
1460 			tty_cursor(tty, nx - 1, aty);
1461 			tty_putcode(tty, TTYC_EL1);
1462 			cleared = 1;
1463 		}
1464 	} else {
1465 		log_debug("%s: wrapped line %u", __func__, aty);
1466 		wrapped = 1;
1467 	}
1468 
1469 	memcpy(&last, &grid_default_cell, sizeof last);
1470 	len = 0;
1471 	width = 0;
1472 
1473 	for (i = 0; i < sx; i++) {
1474 		grid_view_get_cell(gd, px + i, py, &gc);
1475 		gcp = tty_check_codeset(tty, &gc);
1476 		if (len != 0 &&
1477 		    (!tty_check_overlay(tty, atx + ux + width, aty) ||
1478 		    (gcp->attr & GRID_ATTR_CHARSET) ||
1479 		    gcp->flags != last.flags ||
1480 		    gcp->attr != last.attr ||
1481 		    gcp->fg != last.fg ||
1482 		    gcp->bg != last.bg ||
1483 		    gcp->us != last.us ||
1484 		    gcp->link != last.link ||
1485 		    ux + width + gcp->data.width > nx ||
1486 		    (sizeof buf) - len < gcp->data.size)) {
1487 			tty_attributes(tty, &last, defaults, palette,
1488 			    s->hyperlinks);
1489 			if (last.flags & GRID_FLAG_CLEARED) {
1490 				log_debug("%s: %zu cleared", __func__, len);
1491 				tty_clear_line(tty, defaults, aty, atx + ux,
1492 				    width, last.bg);
1493 			} else {
1494 				if (!wrapped || atx != 0 || ux != 0)
1495 					tty_cursor(tty, atx + ux, aty);
1496 				tty_putn(tty, buf, len, width);
1497 			}
1498 			ux += width;
1499 
1500 			len = 0;
1501 			width = 0;
1502 			wrapped = 0;
1503 		}
1504 
1505 		if (gcp->flags & GRID_FLAG_SELECTED)
1506 			screen_select_cell(s, &last, gcp);
1507 		else
1508 			memcpy(&last, gcp, sizeof last);
1509 
1510 		tty_check_overlay_range(tty, atx + ux, aty, gcp->data.width,
1511 		    &r);
1512 		hidden = 0;
1513 		for (j = 0; j < OVERLAY_MAX_RANGES; j++)
1514 			hidden += r.nx[j];
1515 		hidden = gcp->data.width - hidden;
1516 		if (hidden != 0 && hidden == gcp->data.width) {
1517 			if (~gcp->flags & GRID_FLAG_PADDING)
1518 				ux += gcp->data.width;
1519 		} else if (hidden != 0 || ux + gcp->data.width > nx) {
1520 			if (~gcp->flags & GRID_FLAG_PADDING) {
1521 				tty_attributes(tty, &last, defaults, palette,
1522 				    s->hyperlinks);
1523 				for (j = 0; j < OVERLAY_MAX_RANGES; j++) {
1524 					if (r.nx[j] == 0)
1525 						continue;
1526 					/* Effective width drawn so far. */
1527 					eux = r.px[j] - atx;
1528 					if (eux < nx) {
1529 						tty_cursor(tty, r.px[j], aty);
1530 						nxx = nx - eux;
1531 						if (r.nx[j] > nxx)
1532 							r.nx[j] = nxx;
1533 						tty_repeat_space(tty, r.nx[j]);
1534 						ux = eux + r.nx[j];
1535 					}
1536 				}
1537 			}
1538 		} else if (gcp->attr & GRID_ATTR_CHARSET) {
1539 			tty_attributes(tty, &last, defaults, palette,
1540 			    s->hyperlinks);
1541 			tty_cursor(tty, atx + ux, aty);
1542 			for (j = 0; j < gcp->data.size; j++)
1543 				tty_putc(tty, gcp->data.data[j]);
1544 			ux += gcp->data.width;
1545 		} else if (~gcp->flags & GRID_FLAG_PADDING) {
1546 			memcpy(buf + len, gcp->data.data, gcp->data.size);
1547 			len += gcp->data.size;
1548 			width += gcp->data.width;
1549 		}
1550 	}
1551 	if (len != 0 && ((~last.flags & GRID_FLAG_CLEARED) || last.bg != 8)) {
1552 		tty_attributes(tty, &last, defaults, palette, s->hyperlinks);
1553 		if (last.flags & GRID_FLAG_CLEARED) {
1554 			log_debug("%s: %zu cleared (end)", __func__, len);
1555 			tty_clear_line(tty, defaults, aty, atx + ux, width,
1556 			    last.bg);
1557 		} else {
1558 			if (!wrapped || atx != 0 || ux != 0)
1559 				tty_cursor(tty, atx + ux, aty);
1560 			tty_putn(tty, buf, len, width);
1561 		}
1562 		ux += width;
1563 	}
1564 
1565 	if (!cleared && ux < nx) {
1566 		log_debug("%s: %u to end of line (%zu cleared)", __func__,
1567 		    nx - ux, len);
1568 		tty_default_attributes(tty, defaults, palette, 8,
1569 		    s->hyperlinks);
1570 		tty_clear_line(tty, defaults, aty, atx + ux, nx - ux, 8);
1571 	}
1572 
1573 	tty->flags = (tty->flags & ~TTY_NOCURSOR) | flags;
1574 	tty_update_mode(tty, tty->mode, s);
1575 }
1576 
1577 void
1578 tty_sync_start(struct tty *tty)
1579 {
1580 	if (tty->flags & TTY_BLOCK)
1581 		return;
1582 	if (tty->flags & TTY_SYNCING)
1583 		return;
1584 	tty->flags |= TTY_SYNCING;
1585 
1586 	if (tty_term_has(tty->term, TTYC_SYNC)) {
1587 		log_debug("%s sync start", tty->client->name);
1588 		tty_putcode1(tty, TTYC_SYNC, 1);
1589 	}
1590 }
1591 
1592 void
1593 tty_sync_end(struct tty *tty)
1594 {
1595 	if (tty->flags & TTY_BLOCK)
1596 		return;
1597 	if (~tty->flags & TTY_SYNCING)
1598 		return;
1599 	tty->flags &= ~TTY_SYNCING;
1600 
1601 	if (tty_term_has(tty->term, TTYC_SYNC)) {
1602  		log_debug("%s sync end", tty->client->name);
1603 		tty_putcode1(tty, TTYC_SYNC, 2);
1604 	}
1605 }
1606 
1607 static int
1608 tty_client_ready(struct client *c)
1609 {
1610 	if (c->session == NULL || c->tty.term == NULL)
1611 		return (0);
1612 	if (c->flags & (CLIENT_REDRAWWINDOW|CLIENT_SUSPENDED))
1613 		return (0);
1614 	if (c->tty.flags & TTY_FREEZE)
1615 		return (0);
1616 	return (1);
1617 }
1618 
1619 void
1620 tty_write(void (*cmdfn)(struct tty *, const struct tty_ctx *),
1621     struct tty_ctx *ctx)
1622 {
1623 	struct client	*c;
1624 	int		 state;
1625 
1626 	if (ctx->set_client_cb == NULL)
1627 		return;
1628 	TAILQ_FOREACH(c, &clients, entry) {
1629 		if (!tty_client_ready(c))
1630 			continue;
1631 		state = ctx->set_client_cb(ctx, c);
1632 		if (state == -1)
1633 			break;
1634 		if (state == 0)
1635 			continue;
1636 		cmdfn(&c->tty, ctx);
1637 	}
1638 }
1639 
1640 void
1641 tty_cmd_insertcharacter(struct tty *tty, const struct tty_ctx *ctx)
1642 {
1643 	struct client	*c = tty->client;
1644 
1645 	if (ctx->bigger ||
1646 	    !tty_full_width(tty, ctx) ||
1647 	    tty_fake_bce(tty, &ctx->defaults, ctx->bg) ||
1648 	    (!tty_term_has(tty->term, TTYC_ICH) &&
1649 	    !tty_term_has(tty->term, TTYC_ICH1)) ||
1650 	    c->overlay_check != NULL) {
1651 		tty_draw_pane(tty, ctx, ctx->ocy);
1652 		return;
1653 	}
1654 
1655 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1656 	    ctx->s->hyperlinks);
1657 
1658 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1659 
1660 	tty_emulate_repeat(tty, TTYC_ICH, TTYC_ICH1, ctx->num);
1661 }
1662 
1663 void
1664 tty_cmd_deletecharacter(struct tty *tty, const struct tty_ctx *ctx)
1665 {
1666 	struct client	*c = tty->client;
1667 
1668 	if (ctx->bigger ||
1669 	    !tty_full_width(tty, ctx) ||
1670 	    tty_fake_bce(tty, &ctx->defaults, ctx->bg) ||
1671 	    (!tty_term_has(tty->term, TTYC_DCH) &&
1672 	    !tty_term_has(tty->term, TTYC_DCH1)) ||
1673 	    c->overlay_check != NULL) {
1674 		tty_draw_pane(tty, ctx, ctx->ocy);
1675 		return;
1676 	}
1677 
1678 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1679 	    ctx->s->hyperlinks);
1680 
1681 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1682 
1683 	tty_emulate_repeat(tty, TTYC_DCH, TTYC_DCH1, ctx->num);
1684 }
1685 
1686 void
1687 tty_cmd_clearcharacter(struct tty *tty, const struct tty_ctx *ctx)
1688 {
1689 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1690 	    ctx->s->hyperlinks);
1691 
1692 	tty_clear_pane_line(tty, ctx, ctx->ocy, ctx->ocx, ctx->num, ctx->bg);
1693 }
1694 
1695 void
1696 tty_cmd_insertline(struct tty *tty, const struct tty_ctx *ctx)
1697 {
1698 	struct client	*c = tty->client;
1699 
1700 	if (ctx->bigger ||
1701 	    !tty_full_width(tty, ctx) ||
1702 	    tty_fake_bce(tty, &ctx->defaults, ctx->bg) ||
1703 	    !tty_term_has(tty->term, TTYC_CSR) ||
1704 	    !tty_term_has(tty->term, TTYC_IL1) ||
1705 	    ctx->sx == 1 ||
1706 	    ctx->sy == 1 ||
1707 	    c->overlay_check != NULL) {
1708 		tty_redraw_region(tty, ctx);
1709 		return;
1710 	}
1711 
1712 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1713 	    ctx->s->hyperlinks);
1714 
1715 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1716 	tty_margin_off(tty);
1717 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1718 
1719 	tty_emulate_repeat(tty, TTYC_IL, TTYC_IL1, ctx->num);
1720 	tty->cx = tty->cy = UINT_MAX;
1721 }
1722 
1723 void
1724 tty_cmd_deleteline(struct tty *tty, const struct tty_ctx *ctx)
1725 {
1726 	struct client	*c = tty->client;
1727 
1728 	if (ctx->bigger ||
1729 	    !tty_full_width(tty, ctx) ||
1730 	    tty_fake_bce(tty, &ctx->defaults, ctx->bg) ||
1731 	    !tty_term_has(tty->term, TTYC_CSR) ||
1732 	    !tty_term_has(tty->term, TTYC_DL1) ||
1733 	    ctx->sx == 1 ||
1734 	    ctx->sy == 1 ||
1735 	    c->overlay_check != NULL) {
1736 		tty_redraw_region(tty, ctx);
1737 		return;
1738 	}
1739 
1740 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1741 	    ctx->s->hyperlinks);
1742 
1743 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1744 	tty_margin_off(tty);
1745 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1746 
1747 	tty_emulate_repeat(tty, TTYC_DL, TTYC_DL1, ctx->num);
1748 	tty->cx = tty->cy = UINT_MAX;
1749 }
1750 
1751 void
1752 tty_cmd_clearline(struct tty *tty, const struct tty_ctx *ctx)
1753 {
1754 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1755 	    ctx->s->hyperlinks);
1756 
1757 	tty_clear_pane_line(tty, ctx, ctx->ocy, 0, ctx->sx, ctx->bg);
1758 }
1759 
1760 void
1761 tty_cmd_clearendofline(struct tty *tty, const struct tty_ctx *ctx)
1762 {
1763 	u_int	nx = ctx->sx - ctx->ocx;
1764 
1765 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1766 	    ctx->s->hyperlinks);
1767 
1768 	tty_clear_pane_line(tty, ctx, ctx->ocy, ctx->ocx, nx, ctx->bg);
1769 }
1770 
1771 void
1772 tty_cmd_clearstartofline(struct tty *tty, const struct tty_ctx *ctx)
1773 {
1774 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1775 	    ctx->s->hyperlinks);
1776 
1777 	tty_clear_pane_line(tty, ctx, ctx->ocy, 0, ctx->ocx + 1, ctx->bg);
1778 }
1779 
1780 void
1781 tty_cmd_reverseindex(struct tty *tty, const struct tty_ctx *ctx)
1782 {
1783 	struct client	*c = tty->client;
1784 
1785 	if (ctx->ocy != ctx->orupper)
1786 		return;
1787 
1788 	if (ctx->bigger ||
1789 	    (!tty_full_width(tty, ctx) && !tty_use_margin(tty)) ||
1790 	    tty_fake_bce(tty, &ctx->defaults, 8) ||
1791 	    !tty_term_has(tty->term, TTYC_CSR) ||
1792 	    (!tty_term_has(tty->term, TTYC_RI) &&
1793 	    !tty_term_has(tty->term, TTYC_RIN)) ||
1794 	    ctx->sx == 1 ||
1795 	    ctx->sy == 1 ||
1796 	    c->overlay_check != NULL) {
1797 		tty_redraw_region(tty, ctx);
1798 		return;
1799 	}
1800 
1801 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1802 	    ctx->s->hyperlinks);
1803 
1804 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1805 	tty_margin_pane(tty, ctx);
1806 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->orupper);
1807 
1808 	if (tty_term_has(tty->term, TTYC_RI))
1809 		tty_putcode(tty, TTYC_RI);
1810 	else
1811 		tty_putcode1(tty, TTYC_RIN, 1);
1812 }
1813 
1814 void
1815 tty_cmd_linefeed(struct tty *tty, const struct tty_ctx *ctx)
1816 {
1817 	struct client	*c = tty->client;
1818 
1819 	if (ctx->ocy != ctx->orlower)
1820 		return;
1821 
1822 	if (ctx->bigger ||
1823 	    (!tty_full_width(tty, ctx) && !tty_use_margin(tty)) ||
1824 	    tty_fake_bce(tty, &ctx->defaults, 8) ||
1825 	    !tty_term_has(tty->term, TTYC_CSR) ||
1826 	    ctx->sx == 1 ||
1827 	    ctx->sy == 1 ||
1828 	    c->overlay_check != NULL) {
1829 		tty_redraw_region(tty, ctx);
1830 		return;
1831 	}
1832 
1833 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1834 	    ctx->s->hyperlinks);
1835 
1836 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1837 	tty_margin_pane(tty, ctx);
1838 
1839 	/*
1840 	 * If we want to wrap a pane while using margins, the cursor needs to
1841 	 * be exactly on the right of the region. If the cursor is entirely off
1842 	 * the edge - move it back to the right. Some terminals are funny about
1843 	 * this and insert extra spaces, so only use the right if margins are
1844 	 * enabled.
1845 	 */
1846 	if (ctx->xoff + ctx->ocx > tty->rright) {
1847 		if (!tty_use_margin(tty))
1848 			tty_cursor(tty, 0, ctx->yoff + ctx->ocy);
1849 		else
1850 			tty_cursor(tty, tty->rright, ctx->yoff + ctx->ocy);
1851 	} else
1852 		tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1853 
1854 	tty_putc(tty, '\n');
1855 }
1856 
1857 void
1858 tty_cmd_scrollup(struct tty *tty, const struct tty_ctx *ctx)
1859 {
1860 	struct client	*c = tty->client;
1861 	u_int		 i;
1862 
1863 	if (ctx->bigger ||
1864 	    (!tty_full_width(tty, ctx) && !tty_use_margin(tty)) ||
1865 	    tty_fake_bce(tty, &ctx->defaults, 8) ||
1866 	    !tty_term_has(tty->term, TTYC_CSR) ||
1867 	    ctx->sx == 1 ||
1868 	    ctx->sy == 1 ||
1869 	    c->overlay_check != NULL) {
1870 		tty_redraw_region(tty, ctx);
1871 		return;
1872 	}
1873 
1874 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1875 	    ctx->s->hyperlinks);
1876 
1877 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1878 	tty_margin_pane(tty, ctx);
1879 
1880 	if (ctx->num == 1 || !tty_term_has(tty->term, TTYC_INDN)) {
1881 		if (!tty_use_margin(tty))
1882 			tty_cursor(tty, 0, tty->rlower);
1883 		else
1884 			tty_cursor(tty, tty->rright, tty->rlower);
1885 		for (i = 0; i < ctx->num; i++)
1886 			tty_putc(tty, '\n');
1887 	} else {
1888 		if (tty->cy == UINT_MAX)
1889 			tty_cursor(tty, 0, 0);
1890 		else
1891 			tty_cursor(tty, 0, tty->cy);
1892 		tty_putcode1(tty, TTYC_INDN, ctx->num);
1893 	}
1894 }
1895 
1896 void
1897 tty_cmd_scrolldown(struct tty *tty, const struct tty_ctx *ctx)
1898 {
1899 	u_int		 i;
1900 	struct client	*c = tty->client;
1901 
1902 	if (ctx->bigger ||
1903 	    (!tty_full_width(tty, ctx) && !tty_use_margin(tty)) ||
1904 	    tty_fake_bce(tty, &ctx->defaults, 8) ||
1905 	    !tty_term_has(tty->term, TTYC_CSR) ||
1906 	    (!tty_term_has(tty->term, TTYC_RI) &&
1907 	    !tty_term_has(tty->term, TTYC_RIN)) ||
1908 	    ctx->sx == 1 ||
1909 	    ctx->sy == 1 ||
1910 	    c->overlay_check != NULL) {
1911 		tty_redraw_region(tty, ctx);
1912 		return;
1913 	}
1914 
1915 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1916 	    ctx->s->hyperlinks);
1917 
1918 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1919 	tty_margin_pane(tty, ctx);
1920 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->orupper);
1921 
1922 	if (tty_term_has(tty->term, TTYC_RIN))
1923 		tty_putcode1(tty, TTYC_RIN, ctx->num);
1924 	else {
1925 		for (i = 0; i < ctx->num; i++)
1926 			tty_putcode(tty, TTYC_RI);
1927 	}
1928 }
1929 
1930 void
1931 tty_cmd_clearendofscreen(struct tty *tty, const struct tty_ctx *ctx)
1932 {
1933 	u_int	px, py, nx, ny;
1934 
1935 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1936 	    ctx->s->hyperlinks);
1937 
1938 	tty_region_pane(tty, ctx, 0, ctx->sy - 1);
1939 	tty_margin_off(tty);
1940 
1941 	px = 0;
1942 	nx = ctx->sx;
1943 	py = ctx->ocy + 1;
1944 	ny = ctx->sy - ctx->ocy - 1;
1945 
1946 	tty_clear_pane_area(tty, ctx, py, ny, px, nx, ctx->bg);
1947 
1948 	px = ctx->ocx;
1949 	nx = ctx->sx - ctx->ocx;
1950 	py = ctx->ocy;
1951 
1952 	tty_clear_pane_line(tty, ctx, py, px, nx, ctx->bg);
1953 }
1954 
1955 void
1956 tty_cmd_clearstartofscreen(struct tty *tty, const struct tty_ctx *ctx)
1957 {
1958 	u_int	px, py, nx, ny;
1959 
1960 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1961 	    ctx->s->hyperlinks);
1962 
1963 	tty_region_pane(tty, ctx, 0, ctx->sy - 1);
1964 	tty_margin_off(tty);
1965 
1966 	px = 0;
1967 	nx = ctx->sx;
1968 	py = 0;
1969 	ny = ctx->ocy;
1970 
1971 	tty_clear_pane_area(tty, ctx, py, ny, px, nx, ctx->bg);
1972 
1973 	px = 0;
1974 	nx = ctx->ocx + 1;
1975 	py = ctx->ocy;
1976 
1977 	tty_clear_pane_line(tty, ctx, py, px, nx, ctx->bg);
1978 }
1979 
1980 void
1981 tty_cmd_clearscreen(struct tty *tty, const struct tty_ctx *ctx)
1982 {
1983 	u_int	px, py, nx, ny;
1984 
1985 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1986 	    ctx->s->hyperlinks);
1987 
1988 	tty_region_pane(tty, ctx, 0, ctx->sy - 1);
1989 	tty_margin_off(tty);
1990 
1991 	px = 0;
1992 	nx = ctx->sx;
1993 	py = 0;
1994 	ny = ctx->sy;
1995 
1996 	tty_clear_pane_area(tty, ctx, py, ny, px, nx, ctx->bg);
1997 }
1998 
1999 void
2000 tty_cmd_alignmenttest(struct tty *tty, const struct tty_ctx *ctx)
2001 {
2002 	u_int	i, j;
2003 
2004 	if (ctx->bigger) {
2005 		ctx->redraw_cb(ctx);
2006 		return;
2007 	}
2008 
2009 	tty_attributes(tty, &grid_default_cell, &ctx->defaults, ctx->palette,
2010 	    ctx->s->hyperlinks);
2011 
2012 	tty_region_pane(tty, ctx, 0, ctx->sy - 1);
2013 	tty_margin_off(tty);
2014 
2015 	for (j = 0; j < ctx->sy; j++) {
2016 		tty_cursor_pane(tty, ctx, 0, j);
2017 		for (i = 0; i < ctx->sx; i++)
2018 			tty_putc(tty, 'E');
2019 	}
2020 }
2021 
2022 void
2023 tty_cmd_cell(struct tty *tty, const struct tty_ctx *ctx)
2024 {
2025 	const struct grid_cell	*gcp = ctx->cell;
2026 	struct screen		*s = ctx->s;
2027 	struct overlay_ranges	 r;
2028 	u_int			 px, py, i, vis = 0;
2029 
2030 	px = ctx->xoff + ctx->ocx - ctx->wox;
2031 	py = ctx->yoff + ctx->ocy - ctx->woy;
2032 	if (!tty_is_visible(tty, ctx, ctx->ocx, ctx->ocy, 1, 1) ||
2033 	    (gcp->data.width == 1 && !tty_check_overlay(tty, px, py)))
2034 		return;
2035 
2036 	/* Handle partially obstructed wide characters. */
2037 	if (gcp->data.width > 1) {
2038 		tty_check_overlay_range(tty, px, py, gcp->data.width, &r);
2039 		for (i = 0; i < OVERLAY_MAX_RANGES; i++)
2040 			vis += r.nx[i];
2041 		if (vis < gcp->data.width) {
2042 			tty_draw_line(tty, s, s->cx, s->cy, gcp->data.width,
2043 			    px, py, &ctx->defaults, ctx->palette);
2044 			return;
2045 		}
2046 	}
2047 
2048 	if (ctx->xoff + ctx->ocx - ctx->wox > tty->sx - 1 &&
2049 	    ctx->ocy == ctx->orlower &&
2050 	    tty_full_width(tty, ctx))
2051 		tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
2052 
2053 	tty_margin_off(tty);
2054 	tty_cursor_pane_unless_wrap(tty, ctx, ctx->ocx, ctx->ocy);
2055 
2056 	tty_cell(tty, ctx->cell, &ctx->defaults, ctx->palette,
2057 	    ctx->s->hyperlinks);
2058 }
2059 
2060 void
2061 tty_cmd_cells(struct tty *tty, const struct tty_ctx *ctx)
2062 {
2063 	struct overlay_ranges	 r;
2064 	u_int			 i, px, py, cx;
2065 	char			*cp = ctx->ptr;
2066 
2067 	if (!tty_is_visible(tty, ctx, ctx->ocx, ctx->ocy, ctx->num, 1))
2068 		return;
2069 
2070 	if (ctx->bigger &&
2071 	    (ctx->xoff + ctx->ocx < ctx->wox ||
2072 	    ctx->xoff + ctx->ocx + ctx->num > ctx->wox + ctx->wsx)) {
2073 		if (!ctx->wrapped ||
2074 		    !tty_full_width(tty, ctx) ||
2075 		    (tty->term->flags & TERM_NOAM) ||
2076 		    ctx->xoff + ctx->ocx != 0 ||
2077 		    ctx->yoff + ctx->ocy != tty->cy + 1 ||
2078 		    tty->cx < tty->sx ||
2079 		    tty->cy == tty->rlower)
2080 			tty_draw_pane(tty, ctx, ctx->ocy);
2081 		else
2082 			ctx->redraw_cb(ctx);
2083 		return;
2084 	}
2085 
2086 	tty_margin_off(tty);
2087 	tty_cursor_pane_unless_wrap(tty, ctx, ctx->ocx, ctx->ocy);
2088 	tty_attributes(tty, ctx->cell, &ctx->defaults, ctx->palette, ctx->s->hyperlinks);
2089 
2090 	/* Get tty position from pane position for overlay check. */
2091 	px = ctx->xoff + ctx->ocx - ctx->wox;
2092 	py = ctx->yoff + ctx->ocy - ctx->woy;
2093 
2094 	tty_check_overlay_range(tty, px, py, ctx->num, &r);
2095 	for (i = 0; i < OVERLAY_MAX_RANGES; i++) {
2096 		if (r.nx[i] == 0)
2097 			continue;
2098 		/* Convert back to pane position for printing. */
2099 		cx = r.px[i] - ctx->xoff + ctx->wox;
2100 		tty_cursor_pane_unless_wrap(tty, ctx, cx, ctx->ocy);
2101 		tty_putn(tty, cp + r.px[i] - px, r.nx[i], r.nx[i]);
2102 	}
2103 }
2104 
2105 void
2106 tty_cmd_setselection(struct tty *tty, const struct tty_ctx *ctx)
2107 {
2108 	tty_set_selection(tty, ctx->ptr2, ctx->ptr, ctx->num);
2109 }
2110 
2111 void
2112 tty_set_selection(struct tty *tty, const char *flags, const char *buf,
2113     size_t len)
2114 {
2115 	char	*encoded;
2116 	size_t	 size;
2117 
2118 	if (~tty->flags & TTY_STARTED)
2119 		return;
2120 	if (!tty_term_has(tty->term, TTYC_MS))
2121 		return;
2122 
2123 	size = 4 * ((len + 2) / 3) + 1; /* storage for base64 */
2124 	encoded = xmalloc(size);
2125 
2126 	b64_ntop(buf, len, encoded, size);
2127 	tty->flags |= TTY_NOBLOCK;
2128 	tty_putcode_ptr2(tty, TTYC_MS, flags, encoded);
2129 
2130 	free(encoded);
2131 }
2132 
2133 void
2134 tty_cmd_rawstring(struct tty *tty, const struct tty_ctx *ctx)
2135 {
2136 	tty->flags |= TTY_NOBLOCK;
2137 	tty_add(tty, ctx->ptr, ctx->num);
2138 	tty_invalidate(tty);
2139 }
2140 
2141 void
2142 tty_cmd_syncstart(struct tty *tty, const struct tty_ctx *ctx)
2143 {
2144 	if (ctx->num == 0x11) {
2145 		/*
2146 		 * This is an overlay and a command that moves the cursor so
2147 		 * start synchronized updates.
2148 		 */
2149 		tty_sync_start(tty);
2150 	} else if (~ctx->num & 0x10) {
2151 		/*
2152 		 * This is a pane. If there is an overlay, always start;
2153 		 * otherwise, only if requested.
2154 		 */
2155 		if (ctx->num || tty->client->overlay_draw != NULL)
2156 			tty_sync_start(tty);
2157 	}
2158 }
2159 
2160 void
2161 tty_cell(struct tty *tty, const struct grid_cell *gc,
2162     const struct grid_cell *defaults, struct colour_palette *palette,
2163     struct hyperlinks *hl)
2164 {
2165 	const struct grid_cell	*gcp;
2166 
2167 	/* Skip last character if terminal is stupid. */
2168 	if ((tty->term->flags & TERM_NOAM) &&
2169 	    tty->cy == tty->sy - 1 &&
2170 	    tty->cx == tty->sx - 1)
2171 		return;
2172 
2173 	/* If this is a padding character, do nothing. */
2174 	if (gc->flags & GRID_FLAG_PADDING)
2175 		return;
2176 
2177 	/* Check the output codeset and apply attributes. */
2178 	gcp = tty_check_codeset(tty, gc);
2179 	tty_attributes(tty, gcp, defaults, palette, hl);
2180 
2181 	/* If it is a single character, write with putc to handle ACS. */
2182 	if (gcp->data.size == 1) {
2183 		tty_attributes(tty, gcp, defaults, palette, hl);
2184 		if (*gcp->data.data < 0x20 || *gcp->data.data == 0x7f)
2185 			return;
2186 		tty_putc(tty, *gcp->data.data);
2187 		return;
2188 	}
2189 
2190 	/* Write the data. */
2191 	tty_putn(tty, gcp->data.data, gcp->data.size, gcp->data.width);
2192 }
2193 
2194 void
2195 tty_reset(struct tty *tty)
2196 {
2197 	struct grid_cell	*gc = &tty->cell;
2198 
2199 	if (!grid_cells_equal(gc, &grid_default_cell)) {
2200 		if (gc->link != 0)
2201 			tty_putcode_ptr2(tty, TTYC_HLS, "", "");
2202 		if ((gc->attr & GRID_ATTR_CHARSET) && tty_acs_needed(tty))
2203 			tty_putcode(tty, TTYC_RMACS);
2204 		tty_putcode(tty, TTYC_SGR0);
2205 		memcpy(gc, &grid_default_cell, sizeof *gc);
2206 	}
2207 	memcpy(&tty->last_cell, &grid_default_cell, sizeof tty->last_cell);
2208 }
2209 
2210 static void
2211 tty_invalidate(struct tty *tty)
2212 {
2213 	memcpy(&tty->cell, &grid_default_cell, sizeof tty->cell);
2214 	memcpy(&tty->last_cell, &grid_default_cell, sizeof tty->last_cell);
2215 
2216 	tty->cx = tty->cy = UINT_MAX;
2217 	tty->rupper = tty->rleft = UINT_MAX;
2218 	tty->rlower = tty->rright = UINT_MAX;
2219 
2220 	if (tty->flags & TTY_STARTED) {
2221 		if (tty_use_margin(tty))
2222 			tty_putcode(tty, TTYC_ENMG);
2223 		tty_putcode(tty, TTYC_SGR0);
2224 
2225 		tty->mode = ALL_MODES;
2226 		tty_update_mode(tty, MODE_CURSOR, NULL);
2227 
2228 		tty_cursor(tty, 0, 0);
2229 		tty_region_off(tty);
2230 		tty_margin_off(tty);
2231 	} else
2232 		tty->mode = MODE_CURSOR;
2233 }
2234 
2235 /* Turn off margin. */
2236 void
2237 tty_region_off(struct tty *tty)
2238 {
2239 	tty_region(tty, 0, tty->sy - 1);
2240 }
2241 
2242 /* Set region inside pane. */
2243 static void
2244 tty_region_pane(struct tty *tty, const struct tty_ctx *ctx, u_int rupper,
2245     u_int rlower)
2246 {
2247 	tty_region(tty, ctx->yoff + rupper - ctx->woy,
2248 	    ctx->yoff + rlower - ctx->woy);
2249 }
2250 
2251 /* Set region at absolute position. */
2252 static void
2253 tty_region(struct tty *tty, u_int rupper, u_int rlower)
2254 {
2255 	if (tty->rlower == rlower && tty->rupper == rupper)
2256 		return;
2257 	if (!tty_term_has(tty->term, TTYC_CSR))
2258 		return;
2259 
2260 	tty->rupper = rupper;
2261 	tty->rlower = rlower;
2262 
2263 	/*
2264 	 * Some terminals (such as PuTTY) do not correctly reset the cursor to
2265 	 * 0,0 if it is beyond the last column (they do not reset their wrap
2266 	 * flag so further output causes a line feed). As a workaround, do an
2267 	 * explicit move to 0 first.
2268 	 */
2269 	if (tty->cx >= tty->sx) {
2270 		if (tty->cy == UINT_MAX)
2271 			tty_cursor(tty, 0, 0);
2272 		else
2273 			tty_cursor(tty, 0, tty->cy);
2274 	}
2275 
2276 	tty_putcode2(tty, TTYC_CSR, tty->rupper, tty->rlower);
2277 	tty->cx = tty->cy = UINT_MAX;
2278 }
2279 
2280 /* Turn off margin. */
2281 void
2282 tty_margin_off(struct tty *tty)
2283 {
2284 	tty_margin(tty, 0, tty->sx - 1);
2285 }
2286 
2287 /* Set margin inside pane. */
2288 static void
2289 tty_margin_pane(struct tty *tty, const struct tty_ctx *ctx)
2290 {
2291 	tty_margin(tty, ctx->xoff - ctx->wox,
2292 	    ctx->xoff + ctx->sx - 1 - ctx->wox);
2293 }
2294 
2295 /* Set margin at absolute position. */
2296 static void
2297 tty_margin(struct tty *tty, u_int rleft, u_int rright)
2298 {
2299 	if (!tty_use_margin(tty))
2300 		return;
2301 	if (tty->rleft == rleft && tty->rright == rright)
2302 		return;
2303 
2304 	tty_putcode2(tty, TTYC_CSR, tty->rupper, tty->rlower);
2305 
2306 	tty->rleft = rleft;
2307 	tty->rright = rright;
2308 
2309 	if (rleft == 0 && rright == tty->sx - 1)
2310 		tty_putcode(tty, TTYC_CLMG);
2311 	else
2312 		tty_putcode2(tty, TTYC_CMG, rleft, rright);
2313 	tty->cx = tty->cy = UINT_MAX;
2314 }
2315 
2316 /*
2317  * Move the cursor, unless it would wrap itself when the next character is
2318  * printed.
2319  */
2320 static void
2321 tty_cursor_pane_unless_wrap(struct tty *tty, const struct tty_ctx *ctx,
2322     u_int cx, u_int cy)
2323 {
2324 	if (!ctx->wrapped ||
2325 	    !tty_full_width(tty, ctx) ||
2326 	    (tty->term->flags & TERM_NOAM) ||
2327 	    ctx->xoff + cx != 0 ||
2328 	    ctx->yoff + cy != tty->cy + 1 ||
2329 	    tty->cx < tty->sx ||
2330 	    tty->cy == tty->rlower)
2331 		tty_cursor_pane(tty, ctx, cx, cy);
2332 	else
2333 		log_debug("%s: will wrap at %u,%u", __func__, tty->cx, tty->cy);
2334 }
2335 
2336 /* Move cursor inside pane. */
2337 static void
2338 tty_cursor_pane(struct tty *tty, const struct tty_ctx *ctx, u_int cx, u_int cy)
2339 {
2340 	tty_cursor(tty, ctx->xoff + cx - ctx->wox, ctx->yoff + cy - ctx->woy);
2341 }
2342 
2343 /* Move cursor to absolute position. */
2344 void
2345 tty_cursor(struct tty *tty, u_int cx, u_int cy)
2346 {
2347 	struct tty_term	*term = tty->term;
2348 	u_int		 thisx, thisy;
2349 	int		 change;
2350 
2351 	if (tty->flags & TTY_BLOCK)
2352 		return;
2353 
2354 	thisx = tty->cx;
2355 	thisy = tty->cy;
2356 
2357 	/*
2358 	 * If in the automargin space, and want to be there, do not move.
2359 	 * Otherwise, force the cursor to be in range (and complain).
2360 	 */
2361 	if (cx == thisx && cy == thisy && cx == tty->sx)
2362 		return;
2363 	if (cx > tty->sx - 1) {
2364 		log_debug("%s: x too big %u > %u", __func__, cx, tty->sx - 1);
2365 		cx = tty->sx - 1;
2366 	}
2367 
2368 	/* No change. */
2369 	if (cx == thisx && cy == thisy)
2370 		return;
2371 
2372 	/* Currently at the very end of the line - use absolute movement. */
2373 	if (thisx > tty->sx - 1)
2374 		goto absolute;
2375 
2376 	/* Move to home position (0, 0). */
2377 	if (cx == 0 && cy == 0 && tty_term_has(term, TTYC_HOME)) {
2378 		tty_putcode(tty, TTYC_HOME);
2379 		goto out;
2380 	}
2381 
2382 	/* Zero on the next line. */
2383 	if (cx == 0 && cy == thisy + 1 && thisy != tty->rlower &&
2384 	    (!tty_use_margin(tty) || tty->rleft == 0)) {
2385 		tty_putc(tty, '\r');
2386 		tty_putc(tty, '\n');
2387 		goto out;
2388 	}
2389 
2390 	/* Moving column or row. */
2391 	if (cy == thisy) {
2392 		/*
2393 		 * Moving column only, row staying the same.
2394 		 */
2395 
2396 		/* To left edge. */
2397 		if (cx == 0 && (!tty_use_margin(tty) || tty->rleft == 0)) {
2398 			tty_putc(tty, '\r');
2399 			goto out;
2400 		}
2401 
2402 		/* One to the left. */
2403 		if (cx == thisx - 1 && tty_term_has(term, TTYC_CUB1)) {
2404 			tty_putcode(tty, TTYC_CUB1);
2405 			goto out;
2406 		}
2407 
2408 		/* One to the right. */
2409 		if (cx == thisx + 1 && tty_term_has(term, TTYC_CUF1)) {
2410 			tty_putcode(tty, TTYC_CUF1);
2411 			goto out;
2412 		}
2413 
2414 		/* Calculate difference. */
2415 		change = thisx - cx;	/* +ve left, -ve right */
2416 
2417 		/*
2418 		 * Use HPA if change is larger than absolute, otherwise move
2419 		 * the cursor with CUB/CUF.
2420 		 */
2421 		if ((u_int) abs(change) > cx && tty_term_has(term, TTYC_HPA)) {
2422 			tty_putcode1(tty, TTYC_HPA, cx);
2423 			goto out;
2424 		} else if (change > 0 &&
2425 		    tty_term_has(term, TTYC_CUB) &&
2426 		    !tty_use_margin(tty)) {
2427 			if (change == 2 && tty_term_has(term, TTYC_CUB1)) {
2428 				tty_putcode(tty, TTYC_CUB1);
2429 				tty_putcode(tty, TTYC_CUB1);
2430 				goto out;
2431 			}
2432 			tty_putcode1(tty, TTYC_CUB, change);
2433 			goto out;
2434 		} else if (change < 0 &&
2435 		    tty_term_has(term, TTYC_CUF) &&
2436 		    !tty_use_margin(tty)) {
2437 			tty_putcode1(tty, TTYC_CUF, -change);
2438 			goto out;
2439 		}
2440 	} else if (cx == thisx) {
2441 		/*
2442 		 * Moving row only, column staying the same.
2443 		 */
2444 
2445 		/* One above. */
2446 		if (thisy != tty->rupper &&
2447 		    cy == thisy - 1 && tty_term_has(term, TTYC_CUU1)) {
2448 			tty_putcode(tty, TTYC_CUU1);
2449 			goto out;
2450 		}
2451 
2452 		/* One below. */
2453 		if (thisy != tty->rlower &&
2454 		    cy == thisy + 1 && tty_term_has(term, TTYC_CUD1)) {
2455 			tty_putcode(tty, TTYC_CUD1);
2456 			goto out;
2457 		}
2458 
2459 		/* Calculate difference. */
2460 		change = thisy - cy;	/* +ve up, -ve down */
2461 
2462 		/*
2463 		 * Try to use VPA if change is larger than absolute or if this
2464 		 * change would cross the scroll region, otherwise use CUU/CUD.
2465 		 */
2466 		if ((u_int) abs(change) > cy ||
2467 		    (change < 0 && cy - change > tty->rlower) ||
2468 		    (change > 0 && cy - change < tty->rupper)) {
2469 			    if (tty_term_has(term, TTYC_VPA)) {
2470 				    tty_putcode1(tty, TTYC_VPA, cy);
2471 				    goto out;
2472 			    }
2473 		} else if (change > 0 && tty_term_has(term, TTYC_CUU)) {
2474 			tty_putcode1(tty, TTYC_CUU, change);
2475 			goto out;
2476 		} else if (change < 0 && tty_term_has(term, TTYC_CUD)) {
2477 			tty_putcode1(tty, TTYC_CUD, -change);
2478 			goto out;
2479 		}
2480 	}
2481 
2482 absolute:
2483 	/* Absolute movement. */
2484 	tty_putcode2(tty, TTYC_CUP, cy, cx);
2485 
2486 out:
2487 	tty->cx = cx;
2488 	tty->cy = cy;
2489 }
2490 
2491 static void
2492 tty_hyperlink(struct tty *tty, const struct grid_cell *gc,
2493     struct hyperlinks *hl)
2494 {
2495 	const char	*uri, *id;
2496 
2497 	if (gc->link == tty->cell.link)
2498 		return;
2499 	tty->cell.link = gc->link;
2500 
2501 	if (hl == NULL)
2502 		return;
2503 
2504 	if (gc->link == 0 || !hyperlinks_get(hl, gc->link, &uri, NULL, &id))
2505 		tty_putcode_ptr2(tty, TTYC_HLS, "", "");
2506 	else
2507 		tty_putcode_ptr2(tty, TTYC_HLS, id, uri);
2508 }
2509 
2510 void
2511 tty_attributes(struct tty *tty, const struct grid_cell *gc,
2512     const struct grid_cell *defaults, struct colour_palette *palette,
2513     struct hyperlinks *hl)
2514 {
2515 	struct grid_cell	*tc = &tty->cell, gc2;
2516 	int			 changed;
2517 
2518 	/* Copy cell and update default colours. */
2519 	memcpy(&gc2, gc, sizeof gc2);
2520 	if (~gc->flags & GRID_FLAG_NOPALETTE) {
2521 		if (gc2.fg == 8)
2522 			gc2.fg = defaults->fg;
2523 		if (gc2.bg == 8)
2524 			gc2.bg = defaults->bg;
2525 	}
2526 
2527 	/* Ignore cell if it is the same as the last one. */
2528 	if (gc2.attr == tty->last_cell.attr &&
2529 	    gc2.fg == tty->last_cell.fg &&
2530 	    gc2.bg == tty->last_cell.bg &&
2531 	    gc2.us == tty->last_cell.us &&
2532 		gc2.link == tty->last_cell.link)
2533 		return;
2534 
2535 	/*
2536 	 * If no setab, try to use the reverse attribute as a best-effort for a
2537 	 * non-default background. This is a bit of a hack but it doesn't do
2538 	 * any serious harm and makes a couple of applications happier.
2539 	 */
2540 	if (!tty_term_has(tty->term, TTYC_SETAB)) {
2541 		if (gc2.attr & GRID_ATTR_REVERSE) {
2542 			if (gc2.fg != 7 && !COLOUR_DEFAULT(gc2.fg))
2543 				gc2.attr &= ~GRID_ATTR_REVERSE;
2544 		} else {
2545 			if (gc2.bg != 0 && !COLOUR_DEFAULT(gc2.bg))
2546 				gc2.attr |= GRID_ATTR_REVERSE;
2547 		}
2548 	}
2549 
2550 	/* Fix up the colours if necessary. */
2551 	tty_check_fg(tty, palette, &gc2);
2552 	tty_check_bg(tty, palette, &gc2);
2553 	tty_check_us(tty, palette, &gc2);
2554 
2555 	/*
2556 	 * If any bits are being cleared or the underline colour is now default,
2557 	 * reset everything.
2558 	 */
2559 	if ((tc->attr & ~gc2.attr) || (tc->us != gc2.us && gc2.us == 0))
2560 		tty_reset(tty);
2561 
2562 	/*
2563 	 * Set the colours. This may call tty_reset() (so it comes next) and
2564 	 * may add to (NOT remove) the desired attributes.
2565 	 */
2566 	tty_colours(tty, &gc2);
2567 
2568 	/* Filter out attribute bits already set. */
2569 	changed = gc2.attr & ~tc->attr;
2570 	tc->attr = gc2.attr;
2571 
2572 	/* Set the attributes. */
2573 	if (changed & GRID_ATTR_BRIGHT)
2574 		tty_putcode(tty, TTYC_BOLD);
2575 	if (changed & GRID_ATTR_DIM)
2576 		tty_putcode(tty, TTYC_DIM);
2577 	if (changed & GRID_ATTR_ITALICS)
2578 		tty_set_italics(tty);
2579 	if (changed & GRID_ATTR_ALL_UNDERSCORE) {
2580 		if ((changed & GRID_ATTR_UNDERSCORE) ||
2581 		    !tty_term_has(tty->term, TTYC_SMULX))
2582 			tty_putcode(tty, TTYC_SMUL);
2583 		else if (changed & GRID_ATTR_UNDERSCORE_2)
2584 			tty_putcode1(tty, TTYC_SMULX, 2);
2585 		else if (changed & GRID_ATTR_UNDERSCORE_3)
2586 			tty_putcode1(tty, TTYC_SMULX, 3);
2587 		else if (changed & GRID_ATTR_UNDERSCORE_4)
2588 			tty_putcode1(tty, TTYC_SMULX, 4);
2589 		else if (changed & GRID_ATTR_UNDERSCORE_5)
2590 			tty_putcode1(tty, TTYC_SMULX, 5);
2591 	}
2592 	if (changed & GRID_ATTR_BLINK)
2593 		tty_putcode(tty, TTYC_BLINK);
2594 	if (changed & GRID_ATTR_REVERSE) {
2595 		if (tty_term_has(tty->term, TTYC_REV))
2596 			tty_putcode(tty, TTYC_REV);
2597 		else if (tty_term_has(tty->term, TTYC_SMSO))
2598 			tty_putcode(tty, TTYC_SMSO);
2599 	}
2600 	if (changed & GRID_ATTR_HIDDEN)
2601 		tty_putcode(tty, TTYC_INVIS);
2602 	if (changed & GRID_ATTR_STRIKETHROUGH)
2603 		tty_putcode(tty, TTYC_SMXX);
2604 	if (changed & GRID_ATTR_OVERLINE)
2605 		tty_putcode(tty, TTYC_SMOL);
2606 	if ((changed & GRID_ATTR_CHARSET) && tty_acs_needed(tty))
2607 		tty_putcode(tty, TTYC_SMACS);
2608 
2609 	/* Set hyperlink if any. */
2610 	tty_hyperlink(tty, gc, hl);
2611 
2612 	memcpy(&tty->last_cell, &gc2, sizeof tty->last_cell);
2613 }
2614 
2615 static void
2616 tty_colours(struct tty *tty, const struct grid_cell *gc)
2617 {
2618 	struct grid_cell	*tc = &tty->cell;
2619 	int			 have_ax;
2620 
2621 	/* No changes? Nothing is necessary. */
2622 	if (gc->fg == tc->fg && gc->bg == tc->bg && gc->us == tc->us)
2623 		return;
2624 
2625 	/*
2626 	 * Is either the default colour? This is handled specially because the
2627 	 * best solution might be to reset both colours to default, in which
2628 	 * case if only one is default need to fall onward to set the other
2629 	 * colour.
2630 	 */
2631 	if (COLOUR_DEFAULT(gc->fg) || COLOUR_DEFAULT(gc->bg)) {
2632 		/*
2633 		 * If don't have AX but do have op, send sgr0 (op can't
2634 		 * actually be used because it is sometimes the same as sgr0
2635 		 * and sometimes isn't). This resets both colours to default.
2636 		 *
2637 		 * Otherwise, try to set the default colour only as needed.
2638 		 */
2639 		have_ax = tty_term_flag(tty->term, TTYC_AX);
2640 		if (!have_ax && tty_term_has(tty->term, TTYC_OP))
2641 			tty_reset(tty);
2642 		else {
2643 			if (COLOUR_DEFAULT(gc->fg) && !COLOUR_DEFAULT(tc->fg)) {
2644 				if (have_ax)
2645 					tty_puts(tty, "\033[39m");
2646 				else if (tc->fg != 7)
2647 					tty_putcode1(tty, TTYC_SETAF, 7);
2648 				tc->fg = gc->fg;
2649 			}
2650 			if (COLOUR_DEFAULT(gc->bg) && !COLOUR_DEFAULT(tc->bg)) {
2651 				if (have_ax)
2652 					tty_puts(tty, "\033[49m");
2653 				else if (tc->bg != 0)
2654 					tty_putcode1(tty, TTYC_SETAB, 0);
2655 				tc->bg = gc->bg;
2656 			}
2657 		}
2658 	}
2659 
2660 	/* Set the foreground colour. */
2661 	if (!COLOUR_DEFAULT(gc->fg) && gc->fg != tc->fg)
2662 		tty_colours_fg(tty, gc);
2663 
2664 	/*
2665 	 * Set the background colour. This must come after the foreground as
2666 	 * tty_colour_fg() can call tty_reset().
2667 	 */
2668 	if (!COLOUR_DEFAULT(gc->bg) && gc->bg != tc->bg)
2669 		tty_colours_bg(tty, gc);
2670 
2671 	/* Set the underscore colour. */
2672 	if (gc->us != tc->us)
2673 		tty_colours_us(tty, gc);
2674 }
2675 
2676 static void
2677 tty_check_fg(struct tty *tty, struct colour_palette *palette,
2678     struct grid_cell *gc)
2679 {
2680 	u_char	r, g, b;
2681 	u_int	colours;
2682 	int	c;
2683 
2684 	/*
2685 	 * Perform substitution if this pane has a palette. If the bright
2686 	 * attribute is set, use the bright entry in the palette by changing to
2687 	 * the aixterm colour.
2688 	 */
2689 	if (~gc->flags & GRID_FLAG_NOPALETTE) {
2690 		c = gc->fg;
2691 		if (c < 8 && gc->attr & GRID_ATTR_BRIGHT)
2692 			c += 90;
2693 		if ((c = colour_palette_get(palette, c)) != -1)
2694 			gc->fg = c;
2695 	}
2696 
2697 	/* Is this a 24-bit colour? */
2698 	if (gc->fg & COLOUR_FLAG_RGB) {
2699 		/* Not a 24-bit terminal? Translate to 256-colour palette. */
2700 		if (tty->term->flags & TERM_RGBCOLOURS)
2701 			return;
2702 		colour_split_rgb(gc->fg, &r, &g, &b);
2703 		gc->fg = colour_find_rgb(r, g, b);
2704 	}
2705 
2706 	/* How many colours does this terminal have? */
2707 	if (tty->term->flags & TERM_256COLOURS)
2708 		colours = 256;
2709 	else
2710 		colours = tty_term_number(tty->term, TTYC_COLORS);
2711 
2712 	/* Is this a 256-colour colour? */
2713 	if (gc->fg & COLOUR_FLAG_256) {
2714 		/* And not a 256 colour mode? */
2715 		if (colours < 256) {
2716 			gc->fg = colour_256to16(gc->fg);
2717 			if (gc->fg & 8) {
2718 				gc->fg &= 7;
2719 				if (colours >= 16)
2720 					gc->fg += 90;
2721 			}
2722 		}
2723 		return;
2724 	}
2725 
2726 	/* Is this an aixterm colour? */
2727 	if (gc->fg >= 90 && gc->fg <= 97 && colours < 16) {
2728 		gc->fg -= 90;
2729 		gc->attr |= GRID_ATTR_BRIGHT;
2730 	}
2731 }
2732 
2733 static void
2734 tty_check_bg(struct tty *tty, struct colour_palette *palette,
2735     struct grid_cell *gc)
2736 {
2737 	u_char	r, g, b;
2738 	u_int	colours;
2739 	int	c;
2740 
2741 	/* Perform substitution if this pane has a palette. */
2742 	if (~gc->flags & GRID_FLAG_NOPALETTE) {
2743 		if ((c = colour_palette_get(palette, gc->bg)) != -1)
2744 			gc->bg = c;
2745 	}
2746 
2747 	/* Is this a 24-bit colour? */
2748 	if (gc->bg & COLOUR_FLAG_RGB) {
2749 		/* Not a 24-bit terminal? Translate to 256-colour palette. */
2750 		if (tty->term->flags & TERM_RGBCOLOURS)
2751 			return;
2752 		colour_split_rgb(gc->bg, &r, &g, &b);
2753 		gc->bg = colour_find_rgb(r, g, b);
2754 	}
2755 
2756 	/* How many colours does this terminal have? */
2757 	if (tty->term->flags & TERM_256COLOURS)
2758 		colours = 256;
2759 	else
2760 		colours = tty_term_number(tty->term, TTYC_COLORS);
2761 
2762 	/* Is this a 256-colour colour? */
2763 	if (gc->bg & COLOUR_FLAG_256) {
2764 		/*
2765 		 * And not a 256 colour mode? Translate to 16-colour
2766 		 * palette. Bold background doesn't exist portably, so just
2767 		 * discard the bold bit if set.
2768 		 */
2769 		if (colours < 256) {
2770 			gc->bg = colour_256to16(gc->bg);
2771 			if (gc->bg & 8) {
2772 				gc->bg &= 7;
2773 				if (colours >= 16)
2774 					gc->bg += 90;
2775 			}
2776 		}
2777 		return;
2778 	}
2779 
2780 	/* Is this an aixterm colour? */
2781 	if (gc->bg >= 90 && gc->bg <= 97 && colours < 16)
2782 		gc->bg -= 90;
2783 }
2784 
2785 static void
2786 tty_check_us(__unused struct tty *tty, struct colour_palette *palette,
2787     struct grid_cell *gc)
2788 {
2789 	int	c;
2790 
2791 	/* Perform substitution if this pane has a palette. */
2792 	if (~gc->flags & GRID_FLAG_NOPALETTE) {
2793 		if ((c = colour_palette_get(palette, gc->us)) != -1)
2794 			gc->us = c;
2795 	}
2796 
2797 	/* Underscore colour is set as RGB so convert a 256 colour to RGB. */
2798 	if (gc->us & COLOUR_FLAG_256)
2799 		gc->us = colour_256toRGB (gc->us);
2800 }
2801 
2802 static void
2803 tty_colours_fg(struct tty *tty, const struct grid_cell *gc)
2804 {
2805 	struct grid_cell	*tc = &tty->cell;
2806 	char			 s[32];
2807 
2808 	/* Is this a 24-bit or 256-colour colour? */
2809 	if (gc->fg & COLOUR_FLAG_RGB || gc->fg & COLOUR_FLAG_256) {
2810 		if (tty_try_colour(tty, gc->fg, "38") == 0)
2811 			goto save;
2812 		/* Should not get here, already converted in tty_check_fg. */
2813 		return;
2814 	}
2815 
2816 	/* Is this an aixterm bright colour? */
2817 	if (gc->fg >= 90 && gc->fg <= 97) {
2818 		if (tty->term->flags & TERM_256COLOURS) {
2819 			xsnprintf(s, sizeof s, "\033[%dm", gc->fg);
2820 			tty_puts(tty, s);
2821 		} else
2822 			tty_putcode1(tty, TTYC_SETAF, gc->fg - 90 + 8);
2823 		goto save;
2824 	}
2825 
2826 	/* Otherwise set the foreground colour. */
2827 	tty_putcode1(tty, TTYC_SETAF, gc->fg);
2828 
2829 save:
2830 	/* Save the new values in the terminal current cell. */
2831 	tc->fg = gc->fg;
2832 }
2833 
2834 static void
2835 tty_colours_bg(struct tty *tty, const struct grid_cell *gc)
2836 {
2837 	struct grid_cell	*tc = &tty->cell;
2838 	char			 s[32];
2839 
2840 	/* Is this a 24-bit or 256-colour colour? */
2841 	if (gc->bg & COLOUR_FLAG_RGB || gc->bg & COLOUR_FLAG_256) {
2842 		if (tty_try_colour(tty, gc->bg, "48") == 0)
2843 			goto save;
2844 		/* Should not get here, already converted in tty_check_bg. */
2845 		return;
2846 	}
2847 
2848 	/* Is this an aixterm bright colour? */
2849 	if (gc->bg >= 90 && gc->bg <= 97) {
2850 		if (tty->term->flags & TERM_256COLOURS) {
2851 			xsnprintf(s, sizeof s, "\033[%dm", gc->bg + 10);
2852 			tty_puts(tty, s);
2853 		} else
2854 			tty_putcode1(tty, TTYC_SETAB, gc->bg - 90 + 8);
2855 		goto save;
2856 	}
2857 
2858 	/* Otherwise set the background colour. */
2859 	tty_putcode1(tty, TTYC_SETAB, gc->bg);
2860 
2861 save:
2862 	/* Save the new values in the terminal current cell. */
2863 	tc->bg = gc->bg;
2864 }
2865 
2866 static void
2867 tty_colours_us(struct tty *tty, const struct grid_cell *gc)
2868 {
2869 	struct grid_cell	*tc = &tty->cell;
2870 	u_int			 c;
2871 	u_char			 r, g, b;
2872 
2873 	/* Clear underline colour. */
2874 	if (gc->us == 0) {
2875 		tty_putcode(tty, TTYC_OL);
2876 		goto save;
2877 	}
2878 
2879 	/* Must be an RGB colour - this should never happen. */
2880 	if (~gc->us & COLOUR_FLAG_RGB)
2881 		return;
2882 
2883 	/*
2884 	 * Setulc and setal follows the ncurses(3) one argument "direct colour"
2885 	 * capability format. Calculate the colour value.
2886 	 */
2887 	colour_split_rgb(gc->us, &r, &g, &b);
2888 	c = (65536 * r) + (256 * g) + b;
2889 
2890 	/*
2891 	 * Write the colour. Only use setal if the RGB flag is set because the
2892 	 * non-RGB version may be wrong.
2893 	 */
2894 	if (tty_term_has(tty->term, TTYC_SETULC))
2895 		tty_putcode1(tty, TTYC_SETULC, c);
2896 	else if (tty_term_has(tty->term, TTYC_SETAL) &&
2897 	    tty_term_has(tty->term, TTYC_RGB))
2898 		tty_putcode1(tty, TTYC_SETAL, c);
2899 
2900 save:
2901 	/* Save the new values in the terminal current cell. */
2902 	tc->us = gc->us;
2903 }
2904 
2905 static int
2906 tty_try_colour(struct tty *tty, int colour, const char *type)
2907 {
2908 	u_char	r, g, b;
2909 
2910 	if (colour & COLOUR_FLAG_256) {
2911 		if (*type == '3' && tty_term_has(tty->term, TTYC_SETAF))
2912 			tty_putcode1(tty, TTYC_SETAF, colour & 0xff);
2913 		else if (tty_term_has(tty->term, TTYC_SETAB))
2914 			tty_putcode1(tty, TTYC_SETAB, colour & 0xff);
2915 		return (0);
2916 	}
2917 
2918 	if (colour & COLOUR_FLAG_RGB) {
2919 		colour_split_rgb(colour & 0xffffff, &r, &g, &b);
2920 		if (*type == '3' && tty_term_has(tty->term, TTYC_SETRGBF))
2921 			tty_putcode3(tty, TTYC_SETRGBF, r, g, b);
2922 		else if (tty_term_has(tty->term, TTYC_SETRGBB))
2923 			tty_putcode3(tty, TTYC_SETRGBB, r, g, b);
2924 		return (0);
2925 	}
2926 
2927 	return (-1);
2928 }
2929 
2930 static void
2931 tty_window_default_style(struct grid_cell *gc, struct window_pane *wp)
2932 {
2933 	memcpy(gc, &grid_default_cell, sizeof *gc);
2934 	gc->fg = wp->palette.fg;
2935 	gc->bg = wp->palette.bg;
2936 }
2937 
2938 void
2939 tty_default_colours(struct grid_cell *gc, struct window_pane *wp)
2940 {
2941 	struct options		*oo = wp->options;
2942 	struct format_tree	*ft;
2943 
2944 	memcpy(gc, &grid_default_cell, sizeof *gc);
2945 
2946 	if (wp->flags & PANE_STYLECHANGED) {
2947 		log_debug("%%%u: style changed", wp->id);
2948 		wp->flags &= ~PANE_STYLECHANGED;
2949 
2950 		ft = format_create(NULL, NULL, FORMAT_PANE|wp->id,
2951 		    FORMAT_NOJOBS);
2952 		format_defaults(ft, NULL, NULL, NULL, wp);
2953 		tty_window_default_style(&wp->cached_active_gc, wp);
2954 		style_add(&wp->cached_active_gc, oo, "window-active-style", ft);
2955 		tty_window_default_style(&wp->cached_gc, wp);
2956 		style_add(&wp->cached_gc, oo, "window-style", ft);
2957 		format_free(ft);
2958 	}
2959 
2960 	if (gc->fg == 8) {
2961 		if (wp == wp->window->active && wp->cached_active_gc.fg != 8)
2962 			gc->fg = wp->cached_active_gc.fg;
2963 		else
2964 			gc->fg = wp->cached_gc.fg;
2965 	}
2966 
2967 	if (gc->bg == 8) {
2968 		if (wp == wp->window->active && wp->cached_active_gc.bg != 8)
2969 			gc->bg = wp->cached_active_gc.bg;
2970 		else
2971 			gc->bg = wp->cached_gc.bg;
2972 	}
2973 }
2974 
2975 static void
2976 tty_default_attributes(struct tty *tty, const struct grid_cell *defaults,
2977     struct colour_palette *palette, u_int bg, struct hyperlinks *hl)
2978 {
2979 	struct grid_cell	gc;
2980 
2981 	memcpy(&gc, &grid_default_cell, sizeof gc);
2982 	gc.bg = bg;
2983 	tty_attributes(tty, &gc, defaults, palette, hl);
2984 }
2985 
2986 static void
2987 tty_clipboard_query_callback(__unused int fd, __unused short events, void *data)
2988 {
2989 	struct tty	*tty = data;
2990 	struct client	*c = tty->client;
2991 
2992 	c->flags &= ~CLIENT_CLIPBOARDBUFFER;
2993 	free(c->clipboard_panes);
2994 	c->clipboard_panes = NULL;
2995 	c->clipboard_npanes = 0;
2996 
2997 	tty->flags &= ~TTY_OSC52QUERY;
2998 }
2999 
3000 void
3001 tty_clipboard_query(struct tty *tty)
3002 {
3003 	struct timeval	 tv = { .tv_sec = TTY_QUERY_TIMEOUT };
3004 
3005 	if ((~tty->flags & TTY_STARTED) || (tty->flags & TTY_OSC52QUERY))
3006 		return;
3007 	tty_putcode_ptr2(tty, TTYC_MS, "", "?");
3008 
3009 	tty->flags |= TTY_OSC52QUERY;
3010 	evtimer_set(&tty->clipboard_timer, tty_clipboard_query_callback, tty);
3011 	evtimer_add(&tty->clipboard_timer, &tv);
3012 }
3013