xref: /openbsd-src/usr.bin/tmux/tty.c (revision ff0e7be1ebbcc809ea8ad2b6dafe215824da9e46)
1 /* $OpenBSD: tty.c,v 1.430 2023/04/25 09:31:50 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 void	tty_set_italics(struct tty *);
38 static int	tty_try_colour(struct tty *, int, const char *);
39 static void	tty_force_cursor_colour(struct tty *, int);
40 static void	tty_cursor_pane(struct tty *, const struct tty_ctx *, u_int,
41 		    u_int);
42 static void	tty_cursor_pane_unless_wrap(struct tty *,
43 		    const struct tty_ctx *, u_int, u_int);
44 static void	tty_invalidate(struct tty *);
45 static void	tty_colours(struct tty *, const struct grid_cell *);
46 static void	tty_check_fg(struct tty *, struct colour_palette *,
47     		    struct grid_cell *);
48 static void	tty_check_bg(struct tty *, struct colour_palette *,
49     		    struct grid_cell *);
50 static void	tty_check_us(struct tty *, struct colour_palette *,
51     		    struct grid_cell *);
52 static void	tty_colours_fg(struct tty *, const struct grid_cell *);
53 static void	tty_colours_bg(struct tty *, const struct grid_cell *);
54 static void	tty_colours_us(struct tty *, const struct grid_cell *);
55 
56 static void	tty_region_pane(struct tty *, const struct tty_ctx *, u_int,
57 		    u_int);
58 static void	tty_region(struct tty *, u_int, u_int);
59 static void	tty_margin_pane(struct tty *, const struct tty_ctx *);
60 static void	tty_margin(struct tty *, u_int, u_int);
61 static int	tty_large_region(struct tty *, const struct tty_ctx *);
62 static int	tty_fake_bce(const struct tty *, const struct grid_cell *,
63 		    u_int);
64 static void	tty_redraw_region(struct tty *, const struct tty_ctx *);
65 static void	tty_emulate_repeat(struct tty *, enum tty_code_code,
66 		    enum tty_code_code, u_int);
67 static void	tty_repeat_space(struct tty *, u_int);
68 static void	tty_draw_pane(struct tty *, const struct tty_ctx *, u_int);
69 static void	tty_default_attributes(struct tty *, const struct grid_cell *,
70 		    struct colour_palette *, u_int, struct hyperlinks *);
71 static int	tty_check_overlay(struct tty *, u_int, u_int);
72 static void	tty_check_overlay_range(struct tty *, u_int, u_int, u_int,
73 		    struct overlay_ranges *);
74 
75 #define tty_use_margin(tty) \
76 	(tty->term->flags & TERM_DECSLRM)
77 #define tty_full_width(tty, ctx) \
78 	((ctx)->xoff == 0 && (ctx)->sx >= (tty)->sx)
79 
80 #define TTY_BLOCK_INTERVAL (100000 /* 100 milliseconds */)
81 #define TTY_BLOCK_START(tty) (1 + ((tty)->sx * (tty)->sy) * 8)
82 #define TTY_BLOCK_STOP(tty) (1 + ((tty)->sx * (tty)->sy) / 8)
83 
84 #define TTY_QUERY_TIMEOUT 5
85 
86 void
87 tty_create_log(void)
88 {
89 	char	name[64];
90 
91 	xsnprintf(name, sizeof name, "tmux-out-%ld.log", (long)getpid());
92 
93 	tty_log_fd = open(name, O_WRONLY|O_CREAT|O_TRUNC, 0644);
94 	if (tty_log_fd != -1 && fcntl(tty_log_fd, F_SETFD, FD_CLOEXEC) == -1)
95 		fatal("fcntl failed");
96 }
97 
98 int
99 tty_init(struct tty *tty, struct client *c)
100 {
101 	if (!isatty(c->fd))
102 		return (-1);
103 
104 	memset(tty, 0, sizeof *tty);
105 	tty->client = c;
106 
107 	tty->cstyle = SCREEN_CURSOR_DEFAULT;
108 	tty->ccolour = -1;
109 	tty->fg = tty->bg = -1;
110 
111 	if (tcgetattr(c->fd, &tty->tio) != 0)
112 		return (-1);
113 	return (0);
114 }
115 
116 void
117 tty_resize(struct tty *tty)
118 {
119 	struct client	*c = tty->client;
120 	struct winsize	 ws;
121 	u_int		 sx, sy, xpixel, ypixel;
122 
123 	if (ioctl(c->fd, TIOCGWINSZ, &ws) != -1) {
124 		sx = ws.ws_col;
125 		if (sx == 0) {
126 			sx = 80;
127 			xpixel = 0;
128 		} else
129 			xpixel = ws.ws_xpixel / sx;
130 		sy = ws.ws_row;
131 		if (sy == 0) {
132 			sy = 24;
133 			ypixel = 0;
134 		} else
135 			ypixel = ws.ws_ypixel / sy;
136 	} else {
137 		sx = 80;
138 		sy = 24;
139 		xpixel = 0;
140 		ypixel = 0;
141 	}
142 	log_debug("%s: %s now %ux%u (%ux%u)", __func__, c->name, sx, sy,
143 	    xpixel, ypixel);
144 	tty_set_size(tty, sx, sy, xpixel, ypixel);
145 	tty_invalidate(tty);
146 }
147 
148 void
149 tty_set_size(struct tty *tty, u_int sx, u_int sy, u_int xpixel, u_int ypixel)
150 {
151 	tty->sx = sx;
152 	tty->sy = sy;
153 	tty->xpixel = xpixel;
154 	tty->ypixel = ypixel;
155 }
156 
157 static void
158 tty_read_callback(__unused int fd, __unused short events, void *data)
159 {
160 	struct tty	*tty = data;
161 	struct client	*c = tty->client;
162 	const char	*name = c->name;
163 	size_t		 size = EVBUFFER_LENGTH(tty->in);
164 	int		 nread;
165 
166 	nread = evbuffer_read(tty->in, c->fd, -1);
167 	if (nread == 0 || nread == -1) {
168 		if (nread == 0)
169 			log_debug("%s: read closed", name);
170 		else
171 			log_debug("%s: read error: %s", name, strerror(errno));
172 		event_del(&tty->event_in);
173 		server_client_lost(tty->client);
174 		return;
175 	}
176 	log_debug("%s: read %d bytes (already %zu)", name, nread, size);
177 
178 	while (tty_keys_next(tty))
179 		;
180 }
181 
182 static void
183 tty_timer_callback(__unused int fd, __unused short events, void *data)
184 {
185 	struct tty	*tty = data;
186 	struct client	*c = tty->client;
187 	struct timeval	 tv = { .tv_usec = TTY_BLOCK_INTERVAL };
188 
189 	log_debug("%s: %zu discarded", c->name, tty->discarded);
190 
191 	c->flags |= CLIENT_ALLREDRAWFLAGS;
192 	c->discarded += tty->discarded;
193 
194 	if (tty->discarded < TTY_BLOCK_STOP(tty)) {
195 		tty->flags &= ~TTY_BLOCK;
196 		tty_invalidate(tty);
197 		return;
198 	}
199 	tty->discarded = 0;
200 	evtimer_add(&tty->timer, &tv);
201 }
202 
203 static int
204 tty_block_maybe(struct tty *tty)
205 {
206 	struct client	*c = tty->client;
207 	size_t		 size = EVBUFFER_LENGTH(tty->out);
208 	struct timeval	 tv = { .tv_usec = TTY_BLOCK_INTERVAL };
209 
210 	if (size == 0)
211 		tty->flags &= ~TTY_NOBLOCK;
212 	else if (tty->flags & TTY_NOBLOCK)
213 		return (0);
214 
215 	if (size < TTY_BLOCK_START(tty))
216 		return (0);
217 
218 	if (tty->flags & TTY_BLOCK)
219 		return (1);
220 	tty->flags |= TTY_BLOCK;
221 
222 	log_debug("%s: can't keep up, %zu discarded", c->name, size);
223 
224 	evbuffer_drain(tty->out, size);
225 	c->discarded += size;
226 
227 	tty->discarded = 0;
228 	evtimer_add(&tty->timer, &tv);
229 	return (1);
230 }
231 
232 static void
233 tty_write_callback(__unused int fd, __unused short events, void *data)
234 {
235 	struct tty	*tty = data;
236 	struct client	*c = tty->client;
237 	size_t		 size = EVBUFFER_LENGTH(tty->out);
238 	int		 nwrite;
239 
240 	nwrite = evbuffer_write(tty->out, c->fd);
241 	if (nwrite == -1)
242 		return;
243 	log_debug("%s: wrote %d bytes (of %zu)", c->name, nwrite, size);
244 
245 	if (c->redraw > 0) {
246 		if ((size_t)nwrite >= c->redraw)
247 			c->redraw = 0;
248 		else
249 			c->redraw -= nwrite;
250 		log_debug("%s: waiting for redraw, %zu bytes left", c->name,
251 		    c->redraw);
252 	} else if (tty_block_maybe(tty))
253 		return;
254 
255 	if (EVBUFFER_LENGTH(tty->out) != 0)
256 		event_add(&tty->event_out, NULL);
257 }
258 
259 int
260 tty_open(struct tty *tty, char **cause)
261 {
262 	struct client	*c = tty->client;
263 
264 	tty->term = tty_term_create(tty, c->term_name, c->term_caps,
265 	    c->term_ncaps, &c->term_features, cause);
266 	if (tty->term == NULL) {
267 		tty_close(tty);
268 		return (-1);
269 	}
270 	tty->flags |= TTY_OPENED;
271 
272 	tty->flags &= ~(TTY_NOCURSOR|TTY_FREEZE|TTY_BLOCK|TTY_TIMER);
273 
274 	event_set(&tty->event_in, c->fd, EV_PERSIST|EV_READ,
275 	    tty_read_callback, tty);
276 	tty->in = evbuffer_new();
277 	if (tty->in == NULL)
278 		fatal("out of memory");
279 
280 	event_set(&tty->event_out, c->fd, EV_WRITE, tty_write_callback, tty);
281 	tty->out = evbuffer_new();
282 	if (tty->out == NULL)
283 		fatal("out of memory");
284 
285 	evtimer_set(&tty->timer, tty_timer_callback, tty);
286 
287 	tty_start_tty(tty);
288 	tty_keys_build(tty);
289 
290 	return (0);
291 }
292 
293 static void
294 tty_start_timer_callback(__unused int fd, __unused short events, void *data)
295 {
296 	struct tty	*tty = data;
297 	struct client	*c = tty->client;
298 
299 	log_debug("%s: start timer fired", c->name);
300 	if ((tty->flags & (TTY_HAVEDA|TTY_HAVEDA2|TTY_HAVEXDA)) == 0)
301 		tty_update_features(tty);
302 	tty->flags |= TTY_ALL_REQUEST_FLAGS;
303 }
304 
305 void
306 tty_start_tty(struct tty *tty)
307 {
308 	struct client	*c = tty->client;
309 	struct termios	 tio;
310 	struct timeval	 tv = { .tv_sec = TTY_QUERY_TIMEOUT };
311 
312 	setblocking(c->fd, 0);
313 	event_add(&tty->event_in, NULL);
314 
315 	memcpy(&tio, &tty->tio, sizeof tio);
316 	tio.c_iflag &= ~(IXON|IXOFF|ICRNL|INLCR|IGNCR|IMAXBEL|ISTRIP);
317 	tio.c_iflag |= IGNBRK;
318 	tio.c_oflag &= ~(OPOST|ONLCR|OCRNL|ONLRET);
319 	tio.c_lflag &= ~(IEXTEN|ICANON|ECHO|ECHOE|ECHONL|ECHOCTL|ECHOPRT|
320 	    ECHOKE|ISIG);
321 	tio.c_cc[VMIN] = 1;
322 	tio.c_cc[VTIME] = 0;
323 	if (tcsetattr(c->fd, TCSANOW, &tio) == 0)
324 		tcflush(c->fd, TCOFLUSH);
325 
326 	tty_putcode(tty, TTYC_SMCUP);
327 
328 	tty_putcode(tty, TTYC_SMKX);
329 	tty_putcode(tty, TTYC_CLEAR);
330 
331 	if (tty_acs_needed(tty)) {
332 		log_debug("%s: using capabilities for ACS", c->name);
333 		tty_putcode(tty, TTYC_ENACS);
334 	} else
335 		log_debug("%s: using UTF-8 for ACS", c->name);
336 
337 	tty_putcode(tty, TTYC_CNORM);
338 	if (tty_term_has(tty->term, TTYC_KMOUS)) {
339 		tty_puts(tty, "\033[?1000l\033[?1002l\033[?1003l");
340 		tty_puts(tty, "\033[?1006l\033[?1005l");
341 	}
342 	if (tty_term_has(tty->term, TTYC_ENBP))
343 		tty_putcode(tty, TTYC_ENBP);
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->term->flags & TTY_HAVEDA)
367 			tty_puts(tty, "\033[c");
368 		if (~tty->flags & TTY_HAVEDA2)
369 			tty_puts(tty, "\033[>c");
370 		if (~tty->flags & TTY_HAVEXDA)
371 			tty_puts(tty, "\033[>q");
372 		if (~tty->flags & TTY_HAVEFG)
373 			tty_puts(tty, "\033]10;?\033\\");
374 		if (~tty->flags & TTY_HAVEBG)
375 			tty_puts(tty, "\033]11;?\033\\");
376 	} else
377 		tty->flags |= TTY_ALL_REQUEST_FLAGS;
378 }
379 
380 void
381 tty_stop_tty(struct tty *tty)
382 {
383 	struct client	*c = tty->client;
384 	struct winsize	 ws;
385 
386 	if (!(tty->flags & TTY_STARTED))
387 		return;
388 	tty->flags &= ~TTY_STARTED;
389 
390 	evtimer_del(&tty->start_timer);
391 
392 	event_del(&tty->timer);
393 	tty->flags &= ~TTY_BLOCK;
394 
395 	event_del(&tty->event_in);
396 	event_del(&tty->event_out);
397 
398 	/*
399 	 * Be flexible about error handling and try not kill the server just
400 	 * because the fd is invalid. Things like ssh -t can easily leave us
401 	 * with a dead tty.
402 	 */
403 	if (ioctl(c->fd, TIOCGWINSZ, &ws) == -1)
404 		return;
405 	if (tcsetattr(c->fd, TCSANOW, &tty->tio) == -1)
406 		return;
407 
408 	tty_raw(tty, tty_term_string_ii(tty->term, TTYC_CSR, 0, ws.ws_row - 1));
409 	if (tty_acs_needed(tty))
410 		tty_raw(tty, tty_term_string(tty->term, TTYC_RMACS));
411 	tty_raw(tty, tty_term_string(tty->term, TTYC_SGR0));
412 	tty_raw(tty, tty_term_string(tty->term, TTYC_RMKX));
413 	tty_raw(tty, tty_term_string(tty->term, TTYC_CLEAR));
414 	if (tty->cstyle != SCREEN_CURSOR_DEFAULT) {
415 		if (tty_term_has(tty->term, TTYC_SE))
416 			tty_raw(tty, tty_term_string(tty->term, TTYC_SE));
417 		else if (tty_term_has(tty->term, TTYC_SS))
418 			tty_raw(tty, tty_term_string_i(tty->term, TTYC_SS, 0));
419 	}
420 	if (tty->ccolour != -1)
421 		tty_raw(tty, tty_term_string(tty->term, TTYC_CR));
422 
423 	tty_raw(tty, tty_term_string(tty->term, TTYC_CNORM));
424 	if (tty_term_has(tty->term, TTYC_KMOUS)) {
425 		tty_raw(tty, "\033[?1000l\033[?1002l\033[?1003l");
426 		tty_raw(tty, "\033[?1006l\033[?1005l");
427 	}
428 	if (tty_term_has(tty->term, TTYC_DSBP))
429 		tty_raw(tty, tty_term_string(tty->term, TTYC_DSBP));
430 
431 	if (tty->term->flags & TERM_VT100LIKE)
432 		tty_raw(tty, "\033[?7727l");
433 	tty_raw(tty, tty_term_string(tty->term, TTYC_DSFCS));
434 	tty_raw(tty, tty_term_string(tty->term, TTYC_DSEKS));
435 
436 	if (tty_use_margin(tty))
437 		tty_raw(tty, tty_term_string(tty->term, TTYC_DSMG));
438 	tty_raw(tty, tty_term_string(tty->term, TTYC_RMCUP));
439 
440 	setblocking(c->fd, 1);
441 }
442 
443 void
444 tty_close(struct tty *tty)
445 {
446 	if (event_initialized(&tty->key_timer))
447 		evtimer_del(&tty->key_timer);
448 	tty_stop_tty(tty);
449 
450 	if (tty->flags & TTY_OPENED) {
451 		evbuffer_free(tty->in);
452 		event_del(&tty->event_in);
453 		evbuffer_free(tty->out);
454 		event_del(&tty->event_out);
455 
456 		tty_term_free(tty->term);
457 		tty_keys_free(tty);
458 
459 		tty->flags &= ~TTY_OPENED;
460 	}
461 }
462 
463 void
464 tty_free(struct tty *tty)
465 {
466 	tty_close(tty);
467 }
468 
469 void
470 tty_update_features(struct tty *tty)
471 {
472 	struct client	*c = tty->client;
473 
474 	if (tty_apply_features(tty->term, c->term_features))
475 		tty_term_apply_overrides(tty->term);
476 
477 	if (tty_use_margin(tty))
478 		tty_putcode(tty, TTYC_ENMG);
479 	if (options_get_number(global_options, "extended-keys"))
480 		tty_puts(tty, tty_term_string(tty->term, TTYC_ENEKS));
481 	if (options_get_number(global_options, "focus-events"))
482 		tty_puts(tty, tty_term_string(tty->term, TTYC_ENFCS));
483 	if (tty->term->flags & TERM_VT100LIKE)
484 		tty_puts(tty, "\033[?7727h");
485 
486 	tty_invalidate(tty);
487 }
488 
489 void
490 tty_raw(struct tty *tty, const char *s)
491 {
492 	struct client	*c = tty->client;
493 	ssize_t		 n, slen;
494 	u_int		 i;
495 
496 	slen = strlen(s);
497 	for (i = 0; i < 5; i++) {
498 		n = write(c->fd, s, slen);
499 		if (n >= 0) {
500 			s += n;
501 			slen -= n;
502 			if (slen == 0)
503 				break;
504 		} else if (n == -1 && errno != EAGAIN)
505 			break;
506 		usleep(100);
507 	}
508 }
509 
510 void
511 tty_putcode(struct tty *tty, enum tty_code_code code)
512 {
513 	tty_puts(tty, tty_term_string(tty->term, code));
514 }
515 
516 void
517 tty_putcode_i(struct tty *tty, enum tty_code_code code, int a)
518 {
519 	if (a < 0)
520 		return;
521 	tty_puts(tty, tty_term_string_i(tty->term, code, a));
522 }
523 
524 void
525 tty_putcode_ii(struct tty *tty, enum tty_code_code code, int a, int b)
526 {
527 	if (a < 0 || b < 0)
528 		return;
529 	tty_puts(tty, tty_term_string_ii(tty->term, code, a, b));
530 }
531 
532 void
533 tty_putcode_iii(struct tty *tty, enum tty_code_code code, int a, int b, int c)
534 {
535 	if (a < 0 || b < 0 || c < 0)
536 		return;
537 	tty_puts(tty, tty_term_string_iii(tty->term, code, a, b, c));
538 }
539 
540 void
541 tty_putcode_s(struct tty *tty, enum tty_code_code code, const char *a)
542 {
543 	if (a != NULL)
544 		tty_puts(tty, tty_term_string_s(tty->term, code, a));
545 }
546 
547 void
548 tty_putcode_ss(struct tty *tty, enum tty_code_code code, const char *a,
549     const char *b)
550 {
551 	if (a != NULL && b != NULL)
552 		tty_puts(tty, tty_term_string_ss(tty->term, code, a, b));
553 }
554 
555 static void
556 tty_add(struct tty *tty, const char *buf, size_t len)
557 {
558 	struct client	*c = tty->client;
559 
560 	if (tty->flags & TTY_BLOCK) {
561 		tty->discarded += len;
562 		return;
563 	}
564 
565 	evbuffer_add(tty->out, buf, len);
566 	log_debug("%s: %.*s", c->name, (int)len, buf);
567 	c->written += len;
568 
569 	if (tty_log_fd != -1)
570 		write(tty_log_fd, buf, len);
571 	if (tty->flags & TTY_STARTED)
572 		event_add(&tty->event_out, NULL);
573 }
574 
575 void
576 tty_puts(struct tty *tty, const char *s)
577 {
578 	if (*s != '\0')
579 		tty_add(tty, s, strlen(s));
580 }
581 
582 void
583 tty_putc(struct tty *tty, u_char ch)
584 {
585 	const char	*acs;
586 
587 	if ((tty->term->flags & TERM_NOAM) &&
588 	    ch >= 0x20 && ch != 0x7f &&
589 	    tty->cy == tty->sy - 1 &&
590 	    tty->cx + 1 >= tty->sx)
591 		return;
592 
593 	if (tty->cell.attr & GRID_ATTR_CHARSET) {
594 		acs = tty_acs_get(tty, ch);
595 		if (acs != NULL)
596 			tty_add(tty, acs, strlen(acs));
597 		else
598 			tty_add(tty, &ch, 1);
599 	} else
600 		tty_add(tty, &ch, 1);
601 
602 	if (ch >= 0x20 && ch != 0x7f) {
603 		if (tty->cx >= tty->sx) {
604 			tty->cx = 1;
605 			if (tty->cy != tty->rlower)
606 				tty->cy++;
607 
608 			/*
609 			 * On !am terminals, force the cursor position to where
610 			 * we think it should be after a line wrap - this means
611 			 * it works on sensible terminals as well.
612 			 */
613 			if (tty->term->flags & TERM_NOAM)
614 				tty_putcode_ii(tty, TTYC_CUP, tty->cy, tty->cx);
615 		} else
616 			tty->cx++;
617 	}
618 }
619 
620 void
621 tty_putn(struct tty *tty, const void *buf, size_t len, u_int width)
622 {
623 	if ((tty->term->flags & TERM_NOAM) &&
624 	    tty->cy == tty->sy - 1 &&
625 	    tty->cx + len >= tty->sx)
626 		len = tty->sx - tty->cx - 1;
627 
628 	tty_add(tty, buf, len);
629 	if (tty->cx + width > tty->sx) {
630 		tty->cx = (tty->cx + width) - tty->sx;
631 		if (tty->cx <= tty->sx)
632 			tty->cy++;
633 		else
634 			tty->cx = tty->cy = UINT_MAX;
635 	} else
636 		tty->cx += width;
637 }
638 
639 static void
640 tty_set_italics(struct tty *tty)
641 {
642 	const char	*s;
643 
644 	if (tty_term_has(tty->term, TTYC_SITM)) {
645 		s = options_get_string(global_options, "default-terminal");
646 		if (strcmp(s, "screen") != 0 && strncmp(s, "screen-", 7) != 0) {
647 			tty_putcode(tty, TTYC_SITM);
648 			return;
649 		}
650 	}
651 	tty_putcode(tty, TTYC_SMSO);
652 }
653 
654 void
655 tty_set_title(struct tty *tty, const char *title)
656 {
657 	if (!tty_term_has(tty->term, TTYC_TSL) ||
658 	    !tty_term_has(tty->term, TTYC_FSL))
659 		return;
660 
661 	tty_putcode(tty, TTYC_TSL);
662 	tty_puts(tty, title);
663 	tty_putcode(tty, TTYC_FSL);
664 }
665 
666 void
667 tty_set_path(struct tty *tty, const char *title)
668 {
669 	if (!tty_term_has(tty->term, TTYC_SWD) ||
670 	    !tty_term_has(tty->term, TTYC_FSL))
671 		return;
672 
673 	tty_putcode(tty, TTYC_SWD);
674 	tty_puts(tty, title);
675 	tty_putcode(tty, TTYC_FSL);
676 }
677 
678 static void
679 tty_force_cursor_colour(struct tty *tty, int c)
680 {
681 	u_char	r, g, b;
682 	char	s[13];
683 
684 	if (c != -1)
685 		c = colour_force_rgb(c);
686 	if (c == tty->ccolour)
687 		return;
688 	if (c == -1)
689 		tty_putcode(tty, TTYC_CR);
690 	else {
691 		colour_split_rgb(c, &r, &g, &b);
692 		xsnprintf(s, sizeof s, "rgb:%02hhx/%02hhx/%02hhx", r, g, b);
693 		tty_putcode_s(tty, TTYC_CS, s);
694 	}
695 	tty->ccolour = c;
696 }
697 
698 static int
699 tty_update_cursor(struct tty *tty, int mode, struct screen *s)
700 {
701 	enum screen_cursor_style	cstyle;
702 	int				ccolour, changed, cmode = mode;
703 
704 	/* Set cursor colour if changed. */
705 	if (s != NULL) {
706 		ccolour = s->ccolour;
707 		if (s->ccolour == -1)
708 			ccolour = s->default_ccolour;
709 		tty_force_cursor_colour(tty, ccolour);
710 	}
711 
712 	/* If cursor is off, set as invisible. */
713 	if (~cmode & MODE_CURSOR) {
714 		if (tty->mode & MODE_CURSOR)
715 			tty_putcode(tty, TTYC_CIVIS);
716 		return (cmode);
717 	}
718 
719 	/* Check if blinking or very visible flag changed or style changed. */
720 	if (s == NULL)
721 		cstyle = tty->cstyle;
722 	else {
723 		cstyle = s->cstyle;
724 		if (cstyle == SCREEN_CURSOR_DEFAULT) {
725 			if (~cmode & MODE_CURSOR_BLINKING_SET) {
726 				if (s->default_mode & MODE_CURSOR_BLINKING)
727 					cmode |= MODE_CURSOR_BLINKING;
728 				else
729 					cmode &= ~MODE_CURSOR_BLINKING;
730 			}
731 			cstyle = s->default_cstyle;
732 		}
733 	}
734 
735 	/* If nothing changed, do nothing. */
736 	changed = cmode ^ tty->mode;
737 	if ((changed & CURSOR_MODES) == 0 && cstyle == tty->cstyle)
738 		return (cmode);
739 
740 	/*
741 	 * Set cursor style. If an explicit style has been set with DECSCUSR,
742 	 * set it if supported, otherwise send cvvis for blinking styles.
743 	 *
744 	 * If no style, has been set (SCREEN_CURSOR_DEFAULT), then send cvvis
745 	 * if either the blinking or very visible flags are set.
746 	 */
747 	tty_putcode(tty, TTYC_CNORM);
748 	switch (cstyle) {
749 	case SCREEN_CURSOR_DEFAULT:
750 		if (tty->cstyle != SCREEN_CURSOR_DEFAULT) {
751 			if (tty_term_has(tty->term, TTYC_SE))
752 				tty_putcode(tty, TTYC_SE);
753 			else
754 				tty_putcode_i(tty, TTYC_SS, 0);
755 		}
756 		if (cmode & (MODE_CURSOR_BLINKING|MODE_CURSOR_VERY_VISIBLE))
757 			tty_putcode(tty, TTYC_CVVIS);
758 		break;
759 	case SCREEN_CURSOR_BLOCK:
760 		if (tty_term_has(tty->term, TTYC_SS)) {
761 			if (cmode & MODE_CURSOR_BLINKING)
762 				tty_putcode_i(tty, TTYC_SS, 1);
763 			else
764 				tty_putcode_i(tty, TTYC_SS, 2);
765 		} else if (cmode & MODE_CURSOR_BLINKING)
766 			tty_putcode(tty, TTYC_CVVIS);
767 		break;
768 	case SCREEN_CURSOR_UNDERLINE:
769 		if (tty_term_has(tty->term, TTYC_SS)) {
770 			if (cmode & MODE_CURSOR_BLINKING)
771 				tty_putcode_i(tty, TTYC_SS, 3);
772 			else
773 				tty_putcode_i(tty, TTYC_SS, 4);
774 		} else if (cmode & MODE_CURSOR_BLINKING)
775 			tty_putcode(tty, TTYC_CVVIS);
776 		break;
777 	case SCREEN_CURSOR_BAR:
778 		if (tty_term_has(tty->term, TTYC_SS)) {
779 			if (cmode & MODE_CURSOR_BLINKING)
780 				tty_putcode_i(tty, TTYC_SS, 5);
781 			else
782 				tty_putcode_i(tty, TTYC_SS, 6);
783 		} else if (cmode & MODE_CURSOR_BLINKING)
784 			tty_putcode(tty, TTYC_CVVIS);
785 		break;
786 	}
787 	tty->cstyle = cstyle;
788 	return (cmode);
789  }
790 
791 void
792 tty_update_mode(struct tty *tty, int mode, struct screen *s)
793 {
794 	struct tty_term	*term = tty->term;
795 	struct client	*c = tty->client;
796 	int		 changed;
797 
798 	if (tty->flags & TTY_NOCURSOR)
799 		mode &= ~MODE_CURSOR;
800 
801 	if (tty_update_cursor(tty, mode, s) & MODE_CURSOR_BLINKING)
802 		mode |= MODE_CURSOR_BLINKING;
803 	else
804 		mode &= ~MODE_CURSOR_BLINKING;
805 
806 	changed = mode ^ tty->mode;
807 	if (log_get_level() != 0 && changed != 0) {
808 		log_debug("%s: current mode %s", c->name,
809 		    screen_mode_to_string(tty->mode));
810 		log_debug("%s: setting mode %s", c->name,
811 		    screen_mode_to_string(mode));
812 	}
813 
814 	if ((changed & ALL_MOUSE_MODES) && tty_term_has(term, TTYC_KMOUS)) {
815 		/*
816 		 * If the mouse modes have changed, clear then all and apply
817 		 * again. There are differences in how terminals track the
818 		 * various bits.
819 		 */
820 		tty_puts(tty, "\033[?1006l\033[?1000l\033[?1002l\033[?1003l");
821 		if (mode & ALL_MOUSE_MODES)
822 			tty_puts(tty, "\033[?1006h");
823 		if (mode & MODE_MOUSE_ALL)
824 			tty_puts(tty, "\033[?1000h\033[?1002h\033[?1003h");
825 		else if (mode & MODE_MOUSE_BUTTON)
826 			tty_puts(tty, "\033[?1000h\033[?1002h");
827 		else if (mode & MODE_MOUSE_STANDARD)
828 			tty_puts(tty, "\033[?1000h");
829 	}
830 	tty->mode = mode;
831 }
832 
833 static void
834 tty_emulate_repeat(struct tty *tty, enum tty_code_code code,
835     enum tty_code_code code1, u_int n)
836 {
837 	if (tty_term_has(tty->term, code))
838 		tty_putcode_i(tty, code, n);
839 	else {
840 		while (n-- > 0)
841 			tty_putcode(tty, code1);
842 	}
843 }
844 
845 static void
846 tty_repeat_space(struct tty *tty, u_int n)
847 {
848 	static char s[500];
849 
850 	if (*s != ' ')
851 		memset(s, ' ', sizeof s);
852 
853 	while (n > sizeof s) {
854 		tty_putn(tty, s, sizeof s, sizeof s);
855 		n -= sizeof s;
856 	}
857 	if (n != 0)
858 		tty_putn(tty, s, n, n);
859 }
860 
861 /* Is this window bigger than the terminal? */
862 int
863 tty_window_bigger(struct tty *tty)
864 {
865 	struct client	*c = tty->client;
866 	struct window	*w = c->session->curw->window;
867 
868 	return (tty->sx < w->sx || tty->sy - status_line_size(c) < w->sy);
869 }
870 
871 /* What offset should this window be drawn at? */
872 int
873 tty_window_offset(struct tty *tty, u_int *ox, u_int *oy, u_int *sx, u_int *sy)
874 {
875 	*ox = tty->oox;
876 	*oy = tty->ooy;
877 	*sx = tty->osx;
878 	*sy = tty->osy;
879 
880 	return (tty->oflag);
881 }
882 
883 /* What offset should this window be drawn at? */
884 static int
885 tty_window_offset1(struct tty *tty, u_int *ox, u_int *oy, u_int *sx, u_int *sy)
886 {
887 	struct client		*c = tty->client;
888 	struct window		*w = c->session->curw->window;
889 	struct window_pane	*wp = server_client_get_pane(c);
890 	u_int			 cx, cy, lines;
891 
892 	lines = status_line_size(c);
893 
894 	if (tty->sx >= w->sx && tty->sy - lines >= w->sy) {
895 		*ox = 0;
896 		*oy = 0;
897 		*sx = w->sx;
898 		*sy = w->sy;
899 
900 		c->pan_window = NULL;
901 		return (0);
902 	}
903 
904 	*sx = tty->sx;
905 	*sy = tty->sy - lines;
906 
907 	if (c->pan_window == w) {
908 		if (*sx >= w->sx)
909 			c->pan_ox = 0;
910 		else if (c->pan_ox + *sx > w->sx)
911 			c->pan_ox = w->sx - *sx;
912 		*ox = c->pan_ox;
913 		if (*sy >= w->sy)
914 			c->pan_oy = 0;
915 		else if (c->pan_oy + *sy > w->sy)
916 			c->pan_oy = w->sy - *sy;
917 		*oy = c->pan_oy;
918 		return (1);
919 	}
920 
921 	if (~wp->screen->mode & MODE_CURSOR) {
922 		*ox = 0;
923 		*oy = 0;
924 	} else {
925 		cx = wp->xoff + wp->screen->cx;
926 		cy = wp->yoff + wp->screen->cy;
927 
928 		if (cx < *sx)
929 			*ox = 0;
930 		else if (cx > w->sx - *sx)
931 			*ox = w->sx - *sx;
932 		else
933 			*ox = cx - *sx / 2;
934 
935 		if (cy < *sy)
936 			*oy = 0;
937 		else if (cy > w->sy - *sy)
938 			*oy = w->sy - *sy;
939 		else
940 			*oy = cy - *sy / 2;
941 	}
942 
943 	c->pan_window = NULL;
944 	return (1);
945 }
946 
947 /* Update stored offsets for a window and redraw if necessary. */
948 void
949 tty_update_window_offset(struct window *w)
950 {
951 	struct client	*c;
952 
953 	TAILQ_FOREACH(c, &clients, entry) {
954 		if (c->session != NULL &&
955 		    c->session->curw != NULL &&
956 		    c->session->curw->window == w)
957 			tty_update_client_offset(c);
958 	}
959 }
960 
961 /* Update stored offsets for a client and redraw if necessary. */
962 void
963 tty_update_client_offset(struct client *c)
964 {
965 	u_int	ox, oy, sx, sy;
966 
967 	if (~c->flags & CLIENT_TERMINAL)
968 		return;
969 
970 	c->tty.oflag = tty_window_offset1(&c->tty, &ox, &oy, &sx, &sy);
971 	if (ox == c->tty.oox &&
972 	    oy == c->tty.ooy &&
973 	    sx == c->tty.osx &&
974 	    sy == c->tty.osy)
975 		return;
976 
977 	log_debug ("%s: %s offset has changed (%u,%u %ux%u -> %u,%u %ux%u)",
978 	    __func__, c->name, c->tty.oox, c->tty.ooy, c->tty.osx, c->tty.osy,
979 	    ox, oy, sx, sy);
980 
981 	c->tty.oox = ox;
982 	c->tty.ooy = oy;
983 	c->tty.osx = sx;
984 	c->tty.osy = sy;
985 
986 	c->flags |= (CLIENT_REDRAWWINDOW|CLIENT_REDRAWSTATUS);
987 }
988 
989 /*
990  * Is the region large enough to be worth redrawing once later rather than
991  * probably several times now? Currently yes if it is more than 50% of the
992  * pane.
993  */
994 static int
995 tty_large_region(__unused struct tty *tty, const struct tty_ctx *ctx)
996 {
997 	return (ctx->orlower - ctx->orupper >= ctx->sy / 2);
998 }
999 
1000 /*
1001  * Return if BCE is needed but the terminal doesn't have it - it'll need to be
1002  * emulated.
1003  */
1004 static int
1005 tty_fake_bce(const struct tty *tty, const struct grid_cell *gc, u_int bg)
1006 {
1007 	if (tty_term_flag(tty->term, TTYC_BCE))
1008 		return (0);
1009 	if (!COLOUR_DEFAULT(bg) || !COLOUR_DEFAULT(gc->bg))
1010 		return (1);
1011 	return (0);
1012 }
1013 
1014 /*
1015  * Redraw scroll region using data from screen (already updated). Used when
1016  * CSR not supported, or window is a pane that doesn't take up the full
1017  * width of the terminal.
1018  */
1019 static void
1020 tty_redraw_region(struct tty *tty, const struct tty_ctx *ctx)
1021 {
1022 	struct client		*c = tty->client;
1023 	u_int			 i;
1024 
1025 	/*
1026 	 * If region is large, schedule a redraw. In most cases this is likely
1027 	 * to be followed by some more scrolling.
1028 	 */
1029 	if (tty_large_region(tty, ctx)) {
1030 		log_debug("%s: %s large redraw", __func__, c->name);
1031 		ctx->redraw_cb(ctx);
1032 		return;
1033 	}
1034 
1035 	for (i = ctx->orupper; i <= ctx->orlower; i++)
1036 		tty_draw_pane(tty, ctx, i);
1037 }
1038 
1039 /* Is this position visible in the pane? */
1040 static int
1041 tty_is_visible(__unused struct tty *tty, const struct tty_ctx *ctx, u_int px,
1042     u_int py, u_int nx, u_int ny)
1043 {
1044 	u_int	xoff = ctx->rxoff + px, yoff = ctx->ryoff + py;
1045 
1046 	if (!ctx->bigger)
1047 		return (1);
1048 
1049 	if (xoff + nx <= ctx->wox || xoff >= ctx->wox + ctx->wsx ||
1050 	    yoff + ny <= ctx->woy || yoff >= ctx->woy + ctx->wsy)
1051 		return (0);
1052 	return (1);
1053 }
1054 
1055 /* Clamp line position to visible part of pane. */
1056 static int
1057 tty_clamp_line(struct tty *tty, const struct tty_ctx *ctx, u_int px, u_int py,
1058     u_int nx, u_int *i, u_int *x, u_int *rx, u_int *ry)
1059 {
1060 	u_int	xoff = ctx->rxoff + px;
1061 
1062 	if (!tty_is_visible(tty, ctx, px, py, nx, 1))
1063 		return (0);
1064 	*ry = ctx->yoff + py - ctx->woy;
1065 
1066 	if (xoff >= ctx->wox && xoff + nx <= ctx->wox + ctx->wsx) {
1067 		/* All visible. */
1068 		*i = 0;
1069 		*x = ctx->xoff + px - ctx->wox;
1070 		*rx = nx;
1071 	} else if (xoff < ctx->wox && xoff + nx > ctx->wox + ctx->wsx) {
1072 		/* Both left and right not visible. */
1073 		*i = ctx->wox;
1074 		*x = 0;
1075 		*rx = ctx->wsx;
1076 	} else if (xoff < ctx->wox) {
1077 		/* Left not visible. */
1078 		*i = ctx->wox - (ctx->xoff + px);
1079 		*x = 0;
1080 		*rx = nx - *i;
1081 	} else {
1082 		/* Right not visible. */
1083 		*i = 0;
1084 		*x = (ctx->xoff + px) - ctx->wox;
1085 		*rx = ctx->wsx - *x;
1086 	}
1087 	if (*rx > nx)
1088 		fatalx("%s: x too big, %u > %u", __func__, *rx, nx);
1089 
1090 	return (1);
1091 }
1092 
1093 /* Clear a line. */
1094 static void
1095 tty_clear_line(struct tty *tty, const struct grid_cell *defaults, u_int py,
1096     u_int px, u_int nx, u_int bg)
1097 {
1098 	struct client		*c = tty->client;
1099 	struct overlay_ranges	 r;
1100 	u_int			 i;
1101 
1102 	log_debug("%s: %s, %u at %u,%u", __func__, c->name, nx, px, py);
1103 
1104 	/* Nothing to clear. */
1105 	if (nx == 0)
1106 		return;
1107 
1108 	/* If genuine BCE is available, can try escape sequences. */
1109 	if (c->overlay_check == NULL && !tty_fake_bce(tty, defaults, bg)) {
1110 		/* Off the end of the line, use EL if available. */
1111 		if (px + nx >= tty->sx && tty_term_has(tty->term, TTYC_EL)) {
1112 			tty_cursor(tty, px, py);
1113 			tty_putcode(tty, TTYC_EL);
1114 			return;
1115 		}
1116 
1117 		/* At the start of the line. Use EL1. */
1118 		if (px == 0 && tty_term_has(tty->term, TTYC_EL1)) {
1119 			tty_cursor(tty, px + nx - 1, py);
1120 			tty_putcode(tty, TTYC_EL1);
1121 			return;
1122 		}
1123 
1124 		/* Section of line. Use ECH if possible. */
1125 		if (tty_term_has(tty->term, TTYC_ECH)) {
1126 			tty_cursor(tty, px, py);
1127 			tty_putcode_i(tty, TTYC_ECH, nx);
1128 			return;
1129 		}
1130 	}
1131 
1132 	/*
1133 	 * Couldn't use an escape sequence, use spaces. Clear only the visible
1134 	 * bit if there is an overlay.
1135 	 */
1136 	tty_check_overlay_range(tty, px, py, nx, &r);
1137 	for (i = 0; i < OVERLAY_MAX_RANGES; i++) {
1138 		if (r.nx[i] == 0)
1139 			continue;
1140 		tty_cursor(tty, r.px[i], py);
1141 		tty_repeat_space(tty, r.nx[i]);
1142 	}
1143 }
1144 
1145 /* Clear a line, adjusting to visible part of pane. */
1146 static void
1147 tty_clear_pane_line(struct tty *tty, const struct tty_ctx *ctx, u_int py,
1148     u_int px, u_int nx, u_int bg)
1149 {
1150 	struct client	*c = tty->client;
1151 	u_int		 i, x, rx, ry;
1152 
1153 	log_debug("%s: %s, %u at %u,%u", __func__, c->name, nx, px, py);
1154 
1155 	if (tty_clamp_line(tty, ctx, px, py, nx, &i, &x, &rx, &ry))
1156 		tty_clear_line(tty, &ctx->defaults, ry, x, rx, bg);
1157 }
1158 
1159 /* Clamp area position to visible part of pane. */
1160 static int
1161 tty_clamp_area(struct tty *tty, const struct tty_ctx *ctx, u_int px, u_int py,
1162     u_int nx, u_int ny, u_int *i, u_int *j, u_int *x, u_int *y, u_int *rx,
1163     u_int *ry)
1164 {
1165 	u_int	xoff = ctx->rxoff + px, yoff = ctx->ryoff + py;
1166 
1167 	if (!tty_is_visible(tty, ctx, px, py, nx, ny))
1168 		return (0);
1169 
1170 	if (xoff >= ctx->wox && xoff + nx <= ctx->wox + ctx->wsx) {
1171 		/* All visible. */
1172 		*i = 0;
1173 		*x = ctx->xoff + px - ctx->wox;
1174 		*rx = nx;
1175 	} else if (xoff < ctx->wox && xoff + nx > ctx->wox + ctx->wsx) {
1176 		/* Both left and right not visible. */
1177 		*i = ctx->wox;
1178 		*x = 0;
1179 		*rx = ctx->wsx;
1180 	} else if (xoff < ctx->wox) {
1181 		/* Left not visible. */
1182 		*i = ctx->wox - (ctx->xoff + px);
1183 		*x = 0;
1184 		*rx = nx - *i;
1185 	} else {
1186 		/* Right not visible. */
1187 		*i = 0;
1188 		*x = (ctx->xoff + px) - ctx->wox;
1189 		*rx = ctx->wsx - *x;
1190 	}
1191 	if (*rx > nx)
1192 		fatalx("%s: x too big, %u > %u", __func__, *rx, nx);
1193 
1194 	if (yoff >= ctx->woy && yoff + ny <= ctx->woy + ctx->wsy) {
1195 		/* All visible. */
1196 		*j = 0;
1197 		*y = ctx->yoff + py - ctx->woy;
1198 		*ry = ny;
1199 	} else if (yoff < ctx->woy && yoff + ny > ctx->woy + ctx->wsy) {
1200 		/* Both top and bottom not visible. */
1201 		*j = ctx->woy;
1202 		*y = 0;
1203 		*ry = ctx->wsy;
1204 	} else if (yoff < ctx->woy) {
1205 		/* Top not visible. */
1206 		*j = ctx->woy - (ctx->yoff + py);
1207 		*y = 0;
1208 		*ry = ny - *j;
1209 	} else {
1210 		/* Bottom not visible. */
1211 		*j = 0;
1212 		*y = (ctx->yoff + py) - ctx->woy;
1213 		*ry = ctx->wsy - *y;
1214 	}
1215 	if (*ry > ny)
1216 		fatalx("%s: y too big, %u > %u", __func__, *ry, ny);
1217 
1218 	return (1);
1219 }
1220 
1221 /* Clear an area, adjusting to visible part of pane. */
1222 static void
1223 tty_clear_area(struct tty *tty, const struct grid_cell *defaults, u_int py,
1224     u_int ny, u_int px, u_int nx, u_int bg)
1225 {
1226 	struct client	*c = tty->client;
1227 	u_int		 yy;
1228 	char		 tmp[64];
1229 
1230 	log_debug("%s: %s, %u,%u at %u,%u", __func__, c->name, nx, ny, px, py);
1231 
1232 	/* Nothing to clear. */
1233 	if (nx == 0 || ny == 0)
1234 		return;
1235 
1236 	/* If genuine BCE is available, can try escape sequences. */
1237 	if (c->overlay_check == NULL && !tty_fake_bce(tty, defaults, bg)) {
1238 		/* Use ED if clearing off the bottom of the terminal. */
1239 		if (px == 0 &&
1240 		    px + nx >= tty->sx &&
1241 		    py + ny >= tty->sy &&
1242 		    tty_term_has(tty->term, TTYC_ED)) {
1243 			tty_cursor(tty, 0, py);
1244 			tty_putcode(tty, TTYC_ED);
1245 			return;
1246 		}
1247 
1248 		/*
1249 		 * On VT420 compatible terminals we can use DECFRA if the
1250 		 * background colour isn't default (because it doesn't work
1251 		 * after SGR 0).
1252 		 */
1253 		if ((tty->term->flags & TERM_DECFRA) && !COLOUR_DEFAULT(bg)) {
1254 			xsnprintf(tmp, sizeof tmp, "\033[32;%u;%u;%u;%u$x",
1255 			    py + 1, px + 1, py + ny, px + nx);
1256 			tty_puts(tty, tmp);
1257 			return;
1258 		}
1259 
1260 		/* Full lines can be scrolled away to clear them. */
1261 		if (px == 0 &&
1262 		    px + nx >= tty->sx &&
1263 		    ny > 2 &&
1264 		    tty_term_has(tty->term, TTYC_CSR) &&
1265 		    tty_term_has(tty->term, TTYC_INDN)) {
1266 			tty_region(tty, py, py + ny - 1);
1267 			tty_margin_off(tty);
1268 			tty_putcode_i(tty, TTYC_INDN, ny);
1269 			return;
1270 		}
1271 
1272 		/*
1273 		 * If margins are supported, can just scroll the area off to
1274 		 * clear it.
1275 		 */
1276 		if (nx > 2 &&
1277 		    ny > 2 &&
1278 		    tty_term_has(tty->term, TTYC_CSR) &&
1279 		    tty_use_margin(tty) &&
1280 		    tty_term_has(tty->term, TTYC_INDN)) {
1281 			tty_region(tty, py, py + ny - 1);
1282 			tty_margin(tty, px, px + nx - 1);
1283 			tty_putcode_i(tty, TTYC_INDN, ny);
1284 			return;
1285 		}
1286 	}
1287 
1288 	/* Couldn't use an escape sequence, loop over the lines. */
1289 	for (yy = py; yy < py + ny; yy++)
1290 		tty_clear_line(tty, defaults, yy, px, nx, bg);
1291 }
1292 
1293 /* Clear an area in a pane. */
1294 static void
1295 tty_clear_pane_area(struct tty *tty, const struct tty_ctx *ctx, u_int py,
1296     u_int ny, u_int px, u_int nx, u_int bg)
1297 {
1298 	u_int	i, j, x, y, rx, ry;
1299 
1300 	if (tty_clamp_area(tty, ctx, px, py, nx, ny, &i, &j, &x, &y, &rx, &ry))
1301 		tty_clear_area(tty, &ctx->defaults, y, ry, x, rx, bg);
1302 }
1303 
1304 static void
1305 tty_draw_pane(struct tty *tty, const struct tty_ctx *ctx, u_int py)
1306 {
1307 	struct screen	*s = ctx->s;
1308 	u_int		 nx = ctx->sx, i, x, rx, ry;
1309 
1310 	log_debug("%s: %s %u %d", __func__, tty->client->name, py, ctx->bigger);
1311 
1312 	if (!ctx->bigger) {
1313 		tty_draw_line(tty, s, 0, py, nx, ctx->xoff, ctx->yoff + py,
1314 		    &ctx->defaults, ctx->palette);
1315 		return;
1316 	}
1317 	if (tty_clamp_line(tty, ctx, 0, py, nx, &i, &x, &rx, &ry)) {
1318 		tty_draw_line(tty, s, i, py, rx, x, ry, &ctx->defaults,
1319 		    ctx->palette);
1320 	}
1321 }
1322 
1323 static const struct grid_cell *
1324 tty_check_codeset(struct tty *tty, const struct grid_cell *gc)
1325 {
1326 	static struct grid_cell	new;
1327 	int			c;
1328 
1329 	/* Characters less than 0x7f are always fine, no matter what. */
1330 	if (gc->data.size == 1 && *gc->data.data < 0x7f)
1331 		return (gc);
1332 
1333 	/* UTF-8 terminal and a UTF-8 character - fine. */
1334 	if (tty->client->flags & CLIENT_UTF8)
1335 		return (gc);
1336 	memcpy(&new, gc, sizeof new);
1337 
1338 	/* See if this can be mapped to an ACS character. */
1339 	c = tty_acs_reverse_get(tty, gc->data.data, gc->data.size);
1340 	if (c != -1) {
1341 		utf8_set(&new.data, c);
1342 		new.attr |= GRID_ATTR_CHARSET;
1343 		return (&new);
1344 	}
1345 
1346 	/* Replace by the right number of underscores. */
1347 	new.data.size = gc->data.width;
1348 	if (new.data.size > UTF8_SIZE)
1349 		new.data.size = UTF8_SIZE;
1350 	memset(new.data.data, '_', new.data.size);
1351 	return (&new);
1352 }
1353 
1354 /*
1355  * Check if a single character is obstructed by the overlay and return a
1356  * boolean.
1357  */
1358 static int
1359 tty_check_overlay(struct tty *tty, u_int px, u_int py)
1360 {
1361 	struct overlay_ranges	r;
1362 
1363 	/*
1364 	 * A unit width range will always return nx[2] == 0 from a check, even
1365 	 * with multiple overlays, so it's sufficient to check just the first
1366 	 * two entries.
1367 	 */
1368 	tty_check_overlay_range(tty, px, py, 1, &r);
1369 	if (r.nx[0] + r.nx[1] == 0)
1370 		return (0);
1371 	return (1);
1372 }
1373 
1374 /* Return parts of the input range which are visible. */
1375 static void
1376 tty_check_overlay_range(struct tty *tty, u_int px, u_int py, u_int nx,
1377     struct overlay_ranges *r)
1378 {
1379 	struct client	*c = tty->client;
1380 
1381 	if (c->overlay_check == NULL) {
1382 		r->px[0] = px;
1383 		r->nx[0] = nx;
1384 		r->px[1] = 0;
1385 		r->nx[1] = 0;
1386 		r->px[2] = 0;
1387 		r->nx[2] = 0;
1388 		return;
1389 	}
1390 
1391 	c->overlay_check(c, c->overlay_data, px, py, nx, r);
1392 }
1393 
1394 void
1395 tty_draw_line(struct tty *tty, struct screen *s, u_int px, u_int py, u_int nx,
1396     u_int atx, u_int aty, const struct grid_cell *defaults,
1397     struct colour_palette *palette)
1398 {
1399 	struct grid		*gd = s->grid;
1400 	struct grid_cell	 gc, last;
1401 	const struct grid_cell	*gcp;
1402 	struct grid_line	*gl;
1403 	struct client		*c = tty->client;
1404 	struct overlay_ranges	 r;
1405 	u_int			 i, j, ux, sx, width, hidden, eux, nxx;
1406 	u_int			 cellsize;
1407 	int			 flags, cleared = 0, wrapped = 0;
1408 	char			 buf[512];
1409 	size_t			 len;
1410 
1411 	log_debug("%s: px=%u py=%u nx=%u atx=%u aty=%u", __func__,
1412 	    px, py, nx, atx, aty);
1413 	log_debug("%s: defaults: fg=%d, bg=%d", __func__, defaults->fg,
1414 	    defaults->bg);
1415 
1416 	/*
1417 	 * py is the line in the screen to draw.
1418 	 * px is the start x and nx is the width to draw.
1419 	 * atx,aty is the line on the terminal to draw it.
1420 	 */
1421 
1422 	flags = (tty->flags & TTY_NOCURSOR);
1423 	tty->flags |= TTY_NOCURSOR;
1424 	tty_update_mode(tty, tty->mode, s);
1425 
1426 	tty_region_off(tty);
1427 	tty_margin_off(tty);
1428 
1429 	/*
1430 	 * Clamp the width to cellsize - note this is not cellused, because
1431 	 * there may be empty background cells after it (from BCE).
1432 	 */
1433 	sx = screen_size_x(s);
1434 	if (nx > sx)
1435 		nx = sx;
1436 	cellsize = grid_get_line(gd, gd->hsize + py)->cellsize;
1437 	if (sx > cellsize)
1438 		sx = cellsize;
1439 	if (sx > tty->sx)
1440 		sx = tty->sx;
1441 	if (sx > nx)
1442 		sx = nx;
1443 	ux = 0;
1444 
1445 	if (py == 0)
1446 		gl = NULL;
1447 	else
1448 		gl = grid_get_line(gd, gd->hsize + py - 1);
1449 	if (gl == NULL ||
1450 	    (~gl->flags & GRID_LINE_WRAPPED) ||
1451 	    atx != 0 ||
1452 	    tty->cx < tty->sx ||
1453 	    nx < tty->sx) {
1454 		if (nx < tty->sx &&
1455 		    atx == 0 &&
1456 		    px + sx != nx &&
1457 		    tty_term_has(tty->term, TTYC_EL1) &&
1458 		    !tty_fake_bce(tty, defaults, 8) &&
1459 		    c->overlay_check == NULL) {
1460 			tty_default_attributes(tty, defaults, palette, 8,
1461 			    s->hyperlinks);
1462 			tty_cursor(tty, nx - 1, aty);
1463 			tty_putcode(tty, TTYC_EL1);
1464 			cleared = 1;
1465 		}
1466 	} else {
1467 		log_debug("%s: wrapped line %u", __func__, aty);
1468 		wrapped = 1;
1469 	}
1470 
1471 	memcpy(&last, &grid_default_cell, sizeof last);
1472 	len = 0;
1473 	width = 0;
1474 
1475 	for (i = 0; i < sx; i++) {
1476 		grid_view_get_cell(gd, px + i, py, &gc);
1477 		gcp = tty_check_codeset(tty, &gc);
1478 		if (len != 0 &&
1479 		    (!tty_check_overlay(tty, atx + ux + width, aty) ||
1480 		    (gcp->attr & GRID_ATTR_CHARSET) ||
1481 		    gcp->flags != last.flags ||
1482 		    gcp->attr != last.attr ||
1483 		    gcp->fg != last.fg ||
1484 		    gcp->bg != last.bg ||
1485 		    gcp->us != last.us ||
1486 		    gcp->link != last.link ||
1487 		    ux + width + gcp->data.width > nx ||
1488 		    (sizeof buf) - len < gcp->data.size)) {
1489 			tty_attributes(tty, &last, defaults, palette,
1490 			    s->hyperlinks);
1491 			if (last.flags & GRID_FLAG_CLEARED) {
1492 				log_debug("%s: %zu cleared", __func__, len);
1493 				tty_clear_line(tty, defaults, aty, atx + ux,
1494 				    width, last.bg);
1495 			} else {
1496 				if (!wrapped || atx != 0 || ux != 0)
1497 					tty_cursor(tty, atx + ux, aty);
1498 				tty_putn(tty, buf, len, width);
1499 			}
1500 			ux += width;
1501 
1502 			len = 0;
1503 			width = 0;
1504 			wrapped = 0;
1505 		}
1506 
1507 		if (gcp->flags & GRID_FLAG_SELECTED)
1508 			screen_select_cell(s, &last, gcp);
1509 		else
1510 			memcpy(&last, gcp, sizeof last);
1511 
1512 		tty_check_overlay_range(tty, atx + ux, aty, gcp->data.width,
1513 		    &r);
1514 		hidden = 0;
1515 		for (j = 0; j < OVERLAY_MAX_RANGES; j++)
1516 			hidden += r.nx[j];
1517 		hidden = gcp->data.width - hidden;
1518 		if (hidden != 0 && hidden == gcp->data.width) {
1519 			if (~gcp->flags & GRID_FLAG_PADDING)
1520 				ux += gcp->data.width;
1521 		} else if (hidden != 0 || ux + gcp->data.width > nx) {
1522 			if (~gcp->flags & GRID_FLAG_PADDING) {
1523 				tty_attributes(tty, &last, defaults, palette,
1524 				    s->hyperlinks);
1525 				for (j = 0; j < OVERLAY_MAX_RANGES; j++) {
1526 					if (r.nx[j] == 0)
1527 						continue;
1528 					/* Effective width drawn so far. */
1529 					eux = r.px[j] - atx;
1530 					if (eux < nx) {
1531 						tty_cursor(tty, r.px[j], aty);
1532 						nxx = nx - eux;
1533 						if (r.nx[j] > nxx)
1534 							r.nx[j] = nxx;
1535 						tty_repeat_space(tty, r.nx[j]);
1536 						ux = eux + r.nx[j];
1537 					}
1538 				}
1539 			}
1540 		} else if (gcp->attr & GRID_ATTR_CHARSET) {
1541 			tty_attributes(tty, &last, defaults, palette,
1542 			    s->hyperlinks);
1543 			tty_cursor(tty, atx + ux, aty);
1544 			for (j = 0; j < gcp->data.size; j++)
1545 				tty_putc(tty, gcp->data.data[j]);
1546 			ux += gcp->data.width;
1547 		} else if (~gcp->flags & GRID_FLAG_PADDING) {
1548 			memcpy(buf + len, gcp->data.data, gcp->data.size);
1549 			len += gcp->data.size;
1550 			width += gcp->data.width;
1551 		}
1552 	}
1553 	if (len != 0 && ((~last.flags & GRID_FLAG_CLEARED) || last.bg != 8)) {
1554 		tty_attributes(tty, &last, defaults, palette, s->hyperlinks);
1555 		if (last.flags & GRID_FLAG_CLEARED) {
1556 			log_debug("%s: %zu cleared (end)", __func__, len);
1557 			tty_clear_line(tty, defaults, aty, atx + ux, width,
1558 			    last.bg);
1559 		} else {
1560 			if (!wrapped || atx != 0 || ux != 0)
1561 				tty_cursor(tty, atx + ux, aty);
1562 			tty_putn(tty, buf, len, width);
1563 		}
1564 		ux += width;
1565 	}
1566 
1567 	if (!cleared && ux < nx) {
1568 		log_debug("%s: %u to end of line (%zu cleared)", __func__,
1569 		    nx - ux, len);
1570 		tty_default_attributes(tty, defaults, palette, 8,
1571 		    s->hyperlinks);
1572 		tty_clear_line(tty, defaults, aty, atx + ux, nx - ux, 8);
1573 	}
1574 
1575 	tty->flags = (tty->flags & ~TTY_NOCURSOR) | flags;
1576 	tty_update_mode(tty, tty->mode, s);
1577 }
1578 
1579 void
1580 tty_sync_start(struct tty *tty)
1581 {
1582 	if (tty->flags & TTY_BLOCK)
1583 		return;
1584 	if (tty->flags & TTY_SYNCING)
1585 		return;
1586 	tty->flags |= TTY_SYNCING;
1587 
1588 	if (tty_term_has(tty->term, TTYC_SYNC)) {
1589 		log_debug("%s sync start", tty->client->name);
1590 		tty_putcode_i(tty, TTYC_SYNC, 1);
1591 	}
1592 }
1593 
1594 void
1595 tty_sync_end(struct tty *tty)
1596 {
1597 	if (tty->flags & TTY_BLOCK)
1598 		return;
1599 	if (~tty->flags & TTY_SYNCING)
1600 		return;
1601 	tty->flags &= ~TTY_SYNCING;
1602 
1603 	if (tty_term_has(tty->term, TTYC_SYNC)) {
1604  		log_debug("%s sync end", tty->client->name);
1605 		tty_putcode_i(tty, TTYC_SYNC, 2);
1606 	}
1607 }
1608 
1609 static int
1610 tty_client_ready(const struct tty_ctx *ctx, struct client *c)
1611 {
1612 	if (c->session == NULL || c->tty.term == NULL)
1613 		return (0);
1614 	if (c->flags & CLIENT_SUSPENDED)
1615 		return (0);
1616 
1617 	/*
1618 	 * If invisible panes are allowed (used for passthrough), don't care if
1619 	 * redrawing or frozen.
1620 	 */
1621 	if (ctx->allow_invisible_panes)
1622 		return (1);
1623 
1624 	if (c->flags & CLIENT_REDRAWWINDOW)
1625 		return (0);
1626 	if (c->tty.flags & TTY_FREEZE)
1627 		return (0);
1628 	return (1);
1629 }
1630 
1631 void
1632 tty_write(void (*cmdfn)(struct tty *, const struct tty_ctx *),
1633     struct tty_ctx *ctx)
1634 {
1635 	struct client	*c;
1636 	int		 state;
1637 
1638 	if (ctx->set_client_cb == NULL)
1639 		return;
1640 	TAILQ_FOREACH(c, &clients, entry) {
1641 		if (tty_client_ready(ctx, c)) {
1642 			state = ctx->set_client_cb(ctx, c);
1643 			if (state == -1)
1644 				break;
1645 			if (state == 0)
1646 				continue;
1647 			cmdfn(&c->tty, ctx);
1648 		}
1649 	}
1650 }
1651 
1652 void
1653 tty_cmd_insertcharacter(struct tty *tty, const struct tty_ctx *ctx)
1654 {
1655 	struct client	*c = tty->client;
1656 
1657 	if (ctx->bigger ||
1658 	    !tty_full_width(tty, ctx) ||
1659 	    tty_fake_bce(tty, &ctx->defaults, ctx->bg) ||
1660 	    (!tty_term_has(tty->term, TTYC_ICH) &&
1661 	    !tty_term_has(tty->term, TTYC_ICH1)) ||
1662 	    c->overlay_check != NULL) {
1663 		tty_draw_pane(tty, ctx, ctx->ocy);
1664 		return;
1665 	}
1666 
1667 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1668 	    ctx->s->hyperlinks);
1669 
1670 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1671 
1672 	tty_emulate_repeat(tty, TTYC_ICH, TTYC_ICH1, ctx->num);
1673 }
1674 
1675 void
1676 tty_cmd_deletecharacter(struct tty *tty, const struct tty_ctx *ctx)
1677 {
1678 	struct client	*c = tty->client;
1679 
1680 	if (ctx->bigger ||
1681 	    !tty_full_width(tty, ctx) ||
1682 	    tty_fake_bce(tty, &ctx->defaults, ctx->bg) ||
1683 	    (!tty_term_has(tty->term, TTYC_DCH) &&
1684 	    !tty_term_has(tty->term, TTYC_DCH1)) ||
1685 	    c->overlay_check != NULL) {
1686 		tty_draw_pane(tty, ctx, ctx->ocy);
1687 		return;
1688 	}
1689 
1690 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1691 	    ctx->s->hyperlinks);
1692 
1693 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1694 
1695 	tty_emulate_repeat(tty, TTYC_DCH, TTYC_DCH1, ctx->num);
1696 }
1697 
1698 void
1699 tty_cmd_clearcharacter(struct tty *tty, const struct tty_ctx *ctx)
1700 {
1701 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1702 	    ctx->s->hyperlinks);
1703 
1704 	tty_clear_pane_line(tty, ctx, ctx->ocy, ctx->ocx, ctx->num, ctx->bg);
1705 }
1706 
1707 void
1708 tty_cmd_insertline(struct tty *tty, const struct tty_ctx *ctx)
1709 {
1710 	struct client	*c = tty->client;
1711 
1712 	if (ctx->bigger ||
1713 	    !tty_full_width(tty, ctx) ||
1714 	    tty_fake_bce(tty, &ctx->defaults, ctx->bg) ||
1715 	    !tty_term_has(tty->term, TTYC_CSR) ||
1716 	    !tty_term_has(tty->term, TTYC_IL1) ||
1717 	    ctx->sx == 1 ||
1718 	    ctx->sy == 1 ||
1719 	    c->overlay_check != NULL) {
1720 		tty_redraw_region(tty, ctx);
1721 		return;
1722 	}
1723 
1724 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1725 	    ctx->s->hyperlinks);
1726 
1727 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1728 	tty_margin_off(tty);
1729 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1730 
1731 	tty_emulate_repeat(tty, TTYC_IL, TTYC_IL1, ctx->num);
1732 	tty->cx = tty->cy = UINT_MAX;
1733 }
1734 
1735 void
1736 tty_cmd_deleteline(struct tty *tty, const struct tty_ctx *ctx)
1737 {
1738 	struct client	*c = tty->client;
1739 
1740 	if (ctx->bigger ||
1741 	    !tty_full_width(tty, ctx) ||
1742 	    tty_fake_bce(tty, &ctx->defaults, ctx->bg) ||
1743 	    !tty_term_has(tty->term, TTYC_CSR) ||
1744 	    !tty_term_has(tty->term, TTYC_DL1) ||
1745 	    ctx->sx == 1 ||
1746 	    ctx->sy == 1 ||
1747 	    c->overlay_check != NULL) {
1748 		tty_redraw_region(tty, ctx);
1749 		return;
1750 	}
1751 
1752 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1753 	    ctx->s->hyperlinks);
1754 
1755 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1756 	tty_margin_off(tty);
1757 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1758 
1759 	tty_emulate_repeat(tty, TTYC_DL, TTYC_DL1, ctx->num);
1760 	tty->cx = tty->cy = UINT_MAX;
1761 }
1762 
1763 void
1764 tty_cmd_clearline(struct tty *tty, const struct tty_ctx *ctx)
1765 {
1766 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1767 	    ctx->s->hyperlinks);
1768 
1769 	tty_clear_pane_line(tty, ctx, ctx->ocy, 0, ctx->sx, ctx->bg);
1770 }
1771 
1772 void
1773 tty_cmd_clearendofline(struct tty *tty, const struct tty_ctx *ctx)
1774 {
1775 	u_int	nx = ctx->sx - ctx->ocx;
1776 
1777 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1778 	    ctx->s->hyperlinks);
1779 
1780 	tty_clear_pane_line(tty, ctx, ctx->ocy, ctx->ocx, nx, ctx->bg);
1781 }
1782 
1783 void
1784 tty_cmd_clearstartofline(struct tty *tty, const struct tty_ctx *ctx)
1785 {
1786 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1787 	    ctx->s->hyperlinks);
1788 
1789 	tty_clear_pane_line(tty, ctx, ctx->ocy, 0, ctx->ocx + 1, ctx->bg);
1790 }
1791 
1792 void
1793 tty_cmd_reverseindex(struct tty *tty, const struct tty_ctx *ctx)
1794 {
1795 	struct client	*c = tty->client;
1796 
1797 	if (ctx->ocy != ctx->orupper)
1798 		return;
1799 
1800 	if (ctx->bigger ||
1801 	    (!tty_full_width(tty, ctx) && !tty_use_margin(tty)) ||
1802 	    tty_fake_bce(tty, &ctx->defaults, 8) ||
1803 	    !tty_term_has(tty->term, TTYC_CSR) ||
1804 	    (!tty_term_has(tty->term, TTYC_RI) &&
1805 	    !tty_term_has(tty->term, TTYC_RIN)) ||
1806 	    ctx->sx == 1 ||
1807 	    ctx->sy == 1 ||
1808 	    c->overlay_check != NULL) {
1809 		tty_redraw_region(tty, ctx);
1810 		return;
1811 	}
1812 
1813 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1814 	    ctx->s->hyperlinks);
1815 
1816 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1817 	tty_margin_pane(tty, ctx);
1818 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->orupper);
1819 
1820 	if (tty_term_has(tty->term, TTYC_RI))
1821 		tty_putcode(tty, TTYC_RI);
1822 	else
1823 		tty_putcode_i(tty, TTYC_RIN, 1);
1824 }
1825 
1826 void
1827 tty_cmd_linefeed(struct tty *tty, const struct tty_ctx *ctx)
1828 {
1829 	struct client	*c = tty->client;
1830 
1831 	if (ctx->ocy != ctx->orlower)
1832 		return;
1833 
1834 	if (ctx->bigger ||
1835 	    (!tty_full_width(tty, ctx) && !tty_use_margin(tty)) ||
1836 	    tty_fake_bce(tty, &ctx->defaults, 8) ||
1837 	    !tty_term_has(tty->term, TTYC_CSR) ||
1838 	    ctx->sx == 1 ||
1839 	    ctx->sy == 1 ||
1840 	    c->overlay_check != NULL) {
1841 		tty_redraw_region(tty, ctx);
1842 		return;
1843 	}
1844 
1845 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1846 	    ctx->s->hyperlinks);
1847 
1848 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1849 	tty_margin_pane(tty, ctx);
1850 
1851 	/*
1852 	 * If we want to wrap a pane while using margins, the cursor needs to
1853 	 * be exactly on the right of the region. If the cursor is entirely off
1854 	 * the edge - move it back to the right. Some terminals are funny about
1855 	 * this and insert extra spaces, so only use the right if margins are
1856 	 * enabled.
1857 	 */
1858 	if (ctx->xoff + ctx->ocx > tty->rright) {
1859 		if (!tty_use_margin(tty))
1860 			tty_cursor(tty, 0, ctx->yoff + ctx->ocy);
1861 		else
1862 			tty_cursor(tty, tty->rright, ctx->yoff + ctx->ocy);
1863 	} else
1864 		tty_cursor_pane(tty, ctx, ctx->ocx, ctx->ocy);
1865 
1866 	tty_putc(tty, '\n');
1867 }
1868 
1869 void
1870 tty_cmd_scrollup(struct tty *tty, const struct tty_ctx *ctx)
1871 {
1872 	struct client	*c = tty->client;
1873 	u_int		 i;
1874 
1875 	if (ctx->bigger ||
1876 	    (!tty_full_width(tty, ctx) && !tty_use_margin(tty)) ||
1877 	    tty_fake_bce(tty, &ctx->defaults, 8) ||
1878 	    !tty_term_has(tty->term, TTYC_CSR) ||
1879 	    ctx->sx == 1 ||
1880 	    ctx->sy == 1 ||
1881 	    c->overlay_check != NULL) {
1882 		tty_redraw_region(tty, ctx);
1883 		return;
1884 	}
1885 
1886 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1887 	    ctx->s->hyperlinks);
1888 
1889 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1890 	tty_margin_pane(tty, ctx);
1891 
1892 	if (ctx->num == 1 || !tty_term_has(tty->term, TTYC_INDN)) {
1893 		if (!tty_use_margin(tty))
1894 			tty_cursor(tty, 0, tty->rlower);
1895 		else
1896 			tty_cursor(tty, tty->rright, tty->rlower);
1897 		for (i = 0; i < ctx->num; i++)
1898 			tty_putc(tty, '\n');
1899 	} else {
1900 		if (tty->cy == UINT_MAX)
1901 			tty_cursor(tty, 0, 0);
1902 		else
1903 			tty_cursor(tty, 0, tty->cy);
1904 		tty_putcode_i(tty, TTYC_INDN, ctx->num);
1905 	}
1906 }
1907 
1908 void
1909 tty_cmd_scrolldown(struct tty *tty, const struct tty_ctx *ctx)
1910 {
1911 	u_int		 i;
1912 	struct client	*c = tty->client;
1913 
1914 	if (ctx->bigger ||
1915 	    (!tty_full_width(tty, ctx) && !tty_use_margin(tty)) ||
1916 	    tty_fake_bce(tty, &ctx->defaults, 8) ||
1917 	    !tty_term_has(tty->term, TTYC_CSR) ||
1918 	    (!tty_term_has(tty->term, TTYC_RI) &&
1919 	    !tty_term_has(tty->term, TTYC_RIN)) ||
1920 	    ctx->sx == 1 ||
1921 	    ctx->sy == 1 ||
1922 	    c->overlay_check != NULL) {
1923 		tty_redraw_region(tty, ctx);
1924 		return;
1925 	}
1926 
1927 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1928 	    ctx->s->hyperlinks);
1929 
1930 	tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
1931 	tty_margin_pane(tty, ctx);
1932 	tty_cursor_pane(tty, ctx, ctx->ocx, ctx->orupper);
1933 
1934 	if (tty_term_has(tty->term, TTYC_RIN))
1935 		tty_putcode_i(tty, TTYC_RIN, ctx->num);
1936 	else {
1937 		for (i = 0; i < ctx->num; i++)
1938 			tty_putcode(tty, TTYC_RI);
1939 	}
1940 }
1941 
1942 void
1943 tty_cmd_clearendofscreen(struct tty *tty, const struct tty_ctx *ctx)
1944 {
1945 	u_int	px, py, nx, ny;
1946 
1947 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1948 	    ctx->s->hyperlinks);
1949 
1950 	tty_region_pane(tty, ctx, 0, ctx->sy - 1);
1951 	tty_margin_off(tty);
1952 
1953 	px = 0;
1954 	nx = ctx->sx;
1955 	py = ctx->ocy + 1;
1956 	ny = ctx->sy - ctx->ocy - 1;
1957 
1958 	tty_clear_pane_area(tty, ctx, py, ny, px, nx, ctx->bg);
1959 
1960 	px = ctx->ocx;
1961 	nx = ctx->sx - ctx->ocx;
1962 	py = ctx->ocy;
1963 
1964 	tty_clear_pane_line(tty, ctx, py, px, nx, ctx->bg);
1965 }
1966 
1967 void
1968 tty_cmd_clearstartofscreen(struct tty *tty, const struct tty_ctx *ctx)
1969 {
1970 	u_int	px, py, nx, ny;
1971 
1972 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1973 	    ctx->s->hyperlinks);
1974 
1975 	tty_region_pane(tty, ctx, 0, ctx->sy - 1);
1976 	tty_margin_off(tty);
1977 
1978 	px = 0;
1979 	nx = ctx->sx;
1980 	py = 0;
1981 	ny = ctx->ocy;
1982 
1983 	tty_clear_pane_area(tty, ctx, py, ny, px, nx, ctx->bg);
1984 
1985 	px = 0;
1986 	nx = ctx->ocx + 1;
1987 	py = ctx->ocy;
1988 
1989 	tty_clear_pane_line(tty, ctx, py, px, nx, ctx->bg);
1990 }
1991 
1992 void
1993 tty_cmd_clearscreen(struct tty *tty, const struct tty_ctx *ctx)
1994 {
1995 	u_int	px, py, nx, ny;
1996 
1997 	tty_default_attributes(tty, &ctx->defaults, ctx->palette, ctx->bg,
1998 	    ctx->s->hyperlinks);
1999 
2000 	tty_region_pane(tty, ctx, 0, ctx->sy - 1);
2001 	tty_margin_off(tty);
2002 
2003 	px = 0;
2004 	nx = ctx->sx;
2005 	py = 0;
2006 	ny = ctx->sy;
2007 
2008 	tty_clear_pane_area(tty, ctx, py, ny, px, nx, ctx->bg);
2009 }
2010 
2011 void
2012 tty_cmd_alignmenttest(struct tty *tty, const struct tty_ctx *ctx)
2013 {
2014 	u_int	i, j;
2015 
2016 	if (ctx->bigger) {
2017 		ctx->redraw_cb(ctx);
2018 		return;
2019 	}
2020 
2021 	tty_attributes(tty, &grid_default_cell, &ctx->defaults, ctx->palette,
2022 	    ctx->s->hyperlinks);
2023 
2024 	tty_region_pane(tty, ctx, 0, ctx->sy - 1);
2025 	tty_margin_off(tty);
2026 
2027 	for (j = 0; j < ctx->sy; j++) {
2028 		tty_cursor_pane(tty, ctx, 0, j);
2029 		for (i = 0; i < ctx->sx; i++)
2030 			tty_putc(tty, 'E');
2031 	}
2032 }
2033 
2034 void
2035 tty_cmd_cell(struct tty *tty, const struct tty_ctx *ctx)
2036 {
2037 	const struct grid_cell	*gcp = ctx->cell;
2038 	struct screen		*s = ctx->s;
2039 	struct overlay_ranges	 r;
2040 	u_int			 px, py, i, vis = 0;
2041 
2042 	px = ctx->xoff + ctx->ocx - ctx->wox;
2043 	py = ctx->yoff + ctx->ocy - ctx->woy;
2044 	if (!tty_is_visible(tty, ctx, ctx->ocx, ctx->ocy, 1, 1) ||
2045 	    (gcp->data.width == 1 && !tty_check_overlay(tty, px, py)))
2046 		return;
2047 
2048 	/* Handle partially obstructed wide characters. */
2049 	if (gcp->data.width > 1) {
2050 		tty_check_overlay_range(tty, px, py, gcp->data.width, &r);
2051 		for (i = 0; i < OVERLAY_MAX_RANGES; i++)
2052 			vis += r.nx[i];
2053 		if (vis < gcp->data.width) {
2054 			tty_draw_line(tty, s, s->cx, s->cy, gcp->data.width,
2055 			    px, py, &ctx->defaults, ctx->palette);
2056 			return;
2057 		}
2058 	}
2059 
2060 	if (ctx->xoff + ctx->ocx - ctx->wox > tty->sx - 1 &&
2061 	    ctx->ocy == ctx->orlower &&
2062 	    tty_full_width(tty, ctx))
2063 		tty_region_pane(tty, ctx, ctx->orupper, ctx->orlower);
2064 
2065 	tty_margin_off(tty);
2066 	tty_cursor_pane_unless_wrap(tty, ctx, ctx->ocx, ctx->ocy);
2067 
2068 	tty_cell(tty, ctx->cell, &ctx->defaults, ctx->palette,
2069 	    ctx->s->hyperlinks);
2070 }
2071 
2072 void
2073 tty_cmd_cells(struct tty *tty, const struct tty_ctx *ctx)
2074 {
2075 	struct overlay_ranges	 r;
2076 	u_int			 i, px, py, cx;
2077 	char			*cp = ctx->ptr;
2078 
2079 	if (!tty_is_visible(tty, ctx, ctx->ocx, ctx->ocy, ctx->num, 1))
2080 		return;
2081 
2082 	if (ctx->bigger &&
2083 	    (ctx->xoff + ctx->ocx < ctx->wox ||
2084 	    ctx->xoff + ctx->ocx + ctx->num > ctx->wox + ctx->wsx)) {
2085 		if (!ctx->wrapped ||
2086 		    !tty_full_width(tty, ctx) ||
2087 		    (tty->term->flags & TERM_NOAM) ||
2088 		    ctx->xoff + ctx->ocx != 0 ||
2089 		    ctx->yoff + ctx->ocy != tty->cy + 1 ||
2090 		    tty->cx < tty->sx ||
2091 		    tty->cy == tty->rlower)
2092 			tty_draw_pane(tty, ctx, ctx->ocy);
2093 		else
2094 			ctx->redraw_cb(ctx);
2095 		return;
2096 	}
2097 
2098 	tty_margin_off(tty);
2099 	tty_cursor_pane_unless_wrap(tty, ctx, ctx->ocx, ctx->ocy);
2100 	tty_attributes(tty, ctx->cell, &ctx->defaults, ctx->palette, ctx->s->hyperlinks);
2101 
2102 	/* Get tty position from pane position for overlay check. */
2103 	px = ctx->xoff + ctx->ocx - ctx->wox;
2104 	py = ctx->yoff + ctx->ocy - ctx->woy;
2105 
2106 	tty_check_overlay_range(tty, px, py, ctx->num, &r);
2107 	for (i = 0; i < OVERLAY_MAX_RANGES; i++) {
2108 		if (r.nx[i] == 0)
2109 			continue;
2110 		/* Convert back to pane position for printing. */
2111 		cx = r.px[i] - ctx->xoff + ctx->wox;
2112 		tty_cursor_pane_unless_wrap(tty, ctx, cx, ctx->ocy);
2113 		tty_putn(tty, cp + r.px[i] - px, r.nx[i], r.nx[i]);
2114 	}
2115 }
2116 
2117 void
2118 tty_cmd_setselection(struct tty *tty, const struct tty_ctx *ctx)
2119 {
2120 	tty_set_selection(tty, ctx->ptr2, ctx->ptr, ctx->num);
2121 }
2122 
2123 void
2124 tty_set_selection(struct tty *tty, const char *flags, const char *buf,
2125     size_t len)
2126 {
2127 	char	*encoded;
2128 	size_t	 size;
2129 
2130 	if (~tty->flags & TTY_STARTED)
2131 		return;
2132 	if (!tty_term_has(tty->term, TTYC_MS))
2133 		return;
2134 
2135 	size = 4 * ((len + 2) / 3) + 1; /* storage for base64 */
2136 	encoded = xmalloc(size);
2137 
2138 	b64_ntop(buf, len, encoded, size);
2139 	tty->flags |= TTY_NOBLOCK;
2140 	tty_putcode_ss(tty, TTYC_MS, flags, encoded);
2141 
2142 	free(encoded);
2143 }
2144 
2145 void
2146 tty_cmd_rawstring(struct tty *tty, const struct tty_ctx *ctx)
2147 {
2148 	tty->flags |= TTY_NOBLOCK;
2149 	tty_add(tty, ctx->ptr, ctx->num);
2150 	tty_invalidate(tty);
2151 }
2152 
2153 void
2154 tty_cmd_syncstart(struct tty *tty, const struct tty_ctx *ctx)
2155 {
2156 	if (ctx->num == 0x11) {
2157 		/*
2158 		 * This is an overlay and a command that moves the cursor so
2159 		 * start synchronized updates.
2160 		 */
2161 		tty_sync_start(tty);
2162 	} else if (~ctx->num & 0x10) {
2163 		/*
2164 		 * This is a pane. If there is an overlay, always start;
2165 		 * otherwise, only if requested.
2166 		 */
2167 		if (ctx->num || tty->client->overlay_draw != NULL)
2168 			tty_sync_start(tty);
2169 	}
2170 }
2171 
2172 void
2173 tty_cell(struct tty *tty, const struct grid_cell *gc,
2174     const struct grid_cell *defaults, struct colour_palette *palette,
2175     struct hyperlinks *hl)
2176 {
2177 	const struct grid_cell	*gcp;
2178 
2179 	/* Skip last character if terminal is stupid. */
2180 	if ((tty->term->flags & TERM_NOAM) &&
2181 	    tty->cy == tty->sy - 1 &&
2182 	    tty->cx == tty->sx - 1)
2183 		return;
2184 
2185 	/* If this is a padding character, do nothing. */
2186 	if (gc->flags & GRID_FLAG_PADDING)
2187 		return;
2188 
2189 	/* Check the output codeset and apply attributes. */
2190 	gcp = tty_check_codeset(tty, gc);
2191 	tty_attributes(tty, gcp, defaults, palette, hl);
2192 
2193 	/* If it is a single character, write with putc to handle ACS. */
2194 	if (gcp->data.size == 1) {
2195 		tty_attributes(tty, gcp, defaults, palette, hl);
2196 		if (*gcp->data.data < 0x20 || *gcp->data.data == 0x7f)
2197 			return;
2198 		tty_putc(tty, *gcp->data.data);
2199 		return;
2200 	}
2201 
2202 	/* Write the data. */
2203 	tty_putn(tty, gcp->data.data, gcp->data.size, gcp->data.width);
2204 }
2205 
2206 void
2207 tty_reset(struct tty *tty)
2208 {
2209 	struct grid_cell	*gc = &tty->cell;
2210 
2211 	if (!grid_cells_equal(gc, &grid_default_cell)) {
2212 		if (gc->link != 0)
2213 			tty_putcode_ss(tty, TTYC_HLS, "", "");
2214 		if ((gc->attr & GRID_ATTR_CHARSET) && tty_acs_needed(tty))
2215 			tty_putcode(tty, TTYC_RMACS);
2216 		tty_putcode(tty, TTYC_SGR0);
2217 		memcpy(gc, &grid_default_cell, sizeof *gc);
2218 	}
2219 	memcpy(&tty->last_cell, &grid_default_cell, sizeof tty->last_cell);
2220 }
2221 
2222 static void
2223 tty_invalidate(struct tty *tty)
2224 {
2225 	memcpy(&tty->cell, &grid_default_cell, sizeof tty->cell);
2226 	memcpy(&tty->last_cell, &grid_default_cell, sizeof tty->last_cell);
2227 
2228 	tty->cx = tty->cy = UINT_MAX;
2229 	tty->rupper = tty->rleft = UINT_MAX;
2230 	tty->rlower = tty->rright = UINT_MAX;
2231 
2232 	if (tty->flags & TTY_STARTED) {
2233 		if (tty_use_margin(tty))
2234 			tty_putcode(tty, TTYC_ENMG);
2235 		tty_putcode(tty, TTYC_SGR0);
2236 
2237 		tty->mode = ALL_MODES;
2238 		tty_update_mode(tty, MODE_CURSOR, NULL);
2239 
2240 		tty_cursor(tty, 0, 0);
2241 		tty_region_off(tty);
2242 		tty_margin_off(tty);
2243 	} else
2244 		tty->mode = MODE_CURSOR;
2245 }
2246 
2247 /* Turn off margin. */
2248 void
2249 tty_region_off(struct tty *tty)
2250 {
2251 	tty_region(tty, 0, tty->sy - 1);
2252 }
2253 
2254 /* Set region inside pane. */
2255 static void
2256 tty_region_pane(struct tty *tty, const struct tty_ctx *ctx, u_int rupper,
2257     u_int rlower)
2258 {
2259 	tty_region(tty, ctx->yoff + rupper - ctx->woy,
2260 	    ctx->yoff + rlower - ctx->woy);
2261 }
2262 
2263 /* Set region at absolute position. */
2264 static void
2265 tty_region(struct tty *tty, u_int rupper, u_int rlower)
2266 {
2267 	if (tty->rlower == rlower && tty->rupper == rupper)
2268 		return;
2269 	if (!tty_term_has(tty->term, TTYC_CSR))
2270 		return;
2271 
2272 	tty->rupper = rupper;
2273 	tty->rlower = rlower;
2274 
2275 	/*
2276 	 * Some terminals (such as PuTTY) do not correctly reset the cursor to
2277 	 * 0,0 if it is beyond the last column (they do not reset their wrap
2278 	 * flag so further output causes a line feed). As a workaround, do an
2279 	 * explicit move to 0 first.
2280 	 */
2281 	if (tty->cx >= tty->sx) {
2282 		if (tty->cy == UINT_MAX)
2283 			tty_cursor(tty, 0, 0);
2284 		else
2285 			tty_cursor(tty, 0, tty->cy);
2286 	}
2287 
2288 	tty_putcode_ii(tty, TTYC_CSR, tty->rupper, tty->rlower);
2289 	tty->cx = tty->cy = UINT_MAX;
2290 }
2291 
2292 /* Turn off margin. */
2293 void
2294 tty_margin_off(struct tty *tty)
2295 {
2296 	tty_margin(tty, 0, tty->sx - 1);
2297 }
2298 
2299 /* Set margin inside pane. */
2300 static void
2301 tty_margin_pane(struct tty *tty, const struct tty_ctx *ctx)
2302 {
2303 	tty_margin(tty, ctx->xoff - ctx->wox,
2304 	    ctx->xoff + ctx->sx - 1 - ctx->wox);
2305 }
2306 
2307 /* Set margin at absolute position. */
2308 static void
2309 tty_margin(struct tty *tty, u_int rleft, u_int rright)
2310 {
2311 	if (!tty_use_margin(tty))
2312 		return;
2313 	if (tty->rleft == rleft && tty->rright == rright)
2314 		return;
2315 
2316 	tty_putcode_ii(tty, TTYC_CSR, tty->rupper, tty->rlower);
2317 
2318 	tty->rleft = rleft;
2319 	tty->rright = rright;
2320 
2321 	if (rleft == 0 && rright == tty->sx - 1)
2322 		tty_putcode(tty, TTYC_CLMG);
2323 	else
2324 		tty_putcode_ii(tty, TTYC_CMG, rleft, rright);
2325 	tty->cx = tty->cy = UINT_MAX;
2326 }
2327 
2328 /*
2329  * Move the cursor, unless it would wrap itself when the next character is
2330  * printed.
2331  */
2332 static void
2333 tty_cursor_pane_unless_wrap(struct tty *tty, const struct tty_ctx *ctx,
2334     u_int cx, u_int cy)
2335 {
2336 	if (!ctx->wrapped ||
2337 	    !tty_full_width(tty, ctx) ||
2338 	    (tty->term->flags & TERM_NOAM) ||
2339 	    ctx->xoff + cx != 0 ||
2340 	    ctx->yoff + cy != tty->cy + 1 ||
2341 	    tty->cx < tty->sx ||
2342 	    tty->cy == tty->rlower)
2343 		tty_cursor_pane(tty, ctx, cx, cy);
2344 	else
2345 		log_debug("%s: will wrap at %u,%u", __func__, tty->cx, tty->cy);
2346 }
2347 
2348 /* Move cursor inside pane. */
2349 static void
2350 tty_cursor_pane(struct tty *tty, const struct tty_ctx *ctx, u_int cx, u_int cy)
2351 {
2352 	tty_cursor(tty, ctx->xoff + cx - ctx->wox, ctx->yoff + cy - ctx->woy);
2353 }
2354 
2355 /* Move cursor to absolute position. */
2356 void
2357 tty_cursor(struct tty *tty, u_int cx, u_int cy)
2358 {
2359 	struct tty_term	*term = tty->term;
2360 	u_int		 thisx, thisy;
2361 	int		 change;
2362 
2363 	if (tty->flags & TTY_BLOCK)
2364 		return;
2365 
2366 	thisx = tty->cx;
2367 	thisy = tty->cy;
2368 
2369 	/*
2370 	 * If in the automargin space, and want to be there, do not move.
2371 	 * Otherwise, force the cursor to be in range (and complain).
2372 	 */
2373 	if (cx == thisx && cy == thisy && cx == tty->sx)
2374 		return;
2375 	if (cx > tty->sx - 1) {
2376 		log_debug("%s: x too big %u > %u", __func__, cx, tty->sx - 1);
2377 		cx = tty->sx - 1;
2378 	}
2379 
2380 	/* No change. */
2381 	if (cx == thisx && cy == thisy)
2382 		return;
2383 
2384 	/* Currently at the very end of the line - use absolute movement. */
2385 	if (thisx > tty->sx - 1)
2386 		goto absolute;
2387 
2388 	/* Move to home position (0, 0). */
2389 	if (cx == 0 && cy == 0 && tty_term_has(term, TTYC_HOME)) {
2390 		tty_putcode(tty, TTYC_HOME);
2391 		goto out;
2392 	}
2393 
2394 	/* Zero on the next line. */
2395 	if (cx == 0 && cy == thisy + 1 && thisy != tty->rlower &&
2396 	    (!tty_use_margin(tty) || tty->rleft == 0)) {
2397 		tty_putc(tty, '\r');
2398 		tty_putc(tty, '\n');
2399 		goto out;
2400 	}
2401 
2402 	/* Moving column or row. */
2403 	if (cy == thisy) {
2404 		/*
2405 		 * Moving column only, row staying the same.
2406 		 */
2407 
2408 		/* To left edge. */
2409 		if (cx == 0 && (!tty_use_margin(tty) || tty->rleft == 0)) {
2410 			tty_putc(tty, '\r');
2411 			goto out;
2412 		}
2413 
2414 		/* One to the left. */
2415 		if (cx == thisx - 1 && tty_term_has(term, TTYC_CUB1)) {
2416 			tty_putcode(tty, TTYC_CUB1);
2417 			goto out;
2418 		}
2419 
2420 		/* One to the right. */
2421 		if (cx == thisx + 1 && tty_term_has(term, TTYC_CUF1)) {
2422 			tty_putcode(tty, TTYC_CUF1);
2423 			goto out;
2424 		}
2425 
2426 		/* Calculate difference. */
2427 		change = thisx - cx;	/* +ve left, -ve right */
2428 
2429 		/*
2430 		 * Use HPA if change is larger than absolute, otherwise move
2431 		 * the cursor with CUB/CUF.
2432 		 */
2433 		if ((u_int) abs(change) > cx && tty_term_has(term, TTYC_HPA)) {
2434 			tty_putcode_i(tty, TTYC_HPA, cx);
2435 			goto out;
2436 		} else if (change > 0 &&
2437 		    tty_term_has(term, TTYC_CUB) &&
2438 		    !tty_use_margin(tty)) {
2439 			if (change == 2 && tty_term_has(term, TTYC_CUB1)) {
2440 				tty_putcode(tty, TTYC_CUB1);
2441 				tty_putcode(tty, TTYC_CUB1);
2442 				goto out;
2443 			}
2444 			tty_putcode_i(tty, TTYC_CUB, change);
2445 			goto out;
2446 		} else if (change < 0 &&
2447 		    tty_term_has(term, TTYC_CUF) &&
2448 		    !tty_use_margin(tty)) {
2449 			tty_putcode_i(tty, TTYC_CUF, -change);
2450 			goto out;
2451 		}
2452 	} else if (cx == thisx) {
2453 		/*
2454 		 * Moving row only, column staying the same.
2455 		 */
2456 
2457 		/* One above. */
2458 		if (thisy != tty->rupper &&
2459 		    cy == thisy - 1 && tty_term_has(term, TTYC_CUU1)) {
2460 			tty_putcode(tty, TTYC_CUU1);
2461 			goto out;
2462 		}
2463 
2464 		/* One below. */
2465 		if (thisy != tty->rlower &&
2466 		    cy == thisy + 1 && tty_term_has(term, TTYC_CUD1)) {
2467 			tty_putcode(tty, TTYC_CUD1);
2468 			goto out;
2469 		}
2470 
2471 		/* Calculate difference. */
2472 		change = thisy - cy;	/* +ve up, -ve down */
2473 
2474 		/*
2475 		 * Try to use VPA if change is larger than absolute or if this
2476 		 * change would cross the scroll region, otherwise use CUU/CUD.
2477 		 */
2478 		if ((u_int) abs(change) > cy ||
2479 		    (change < 0 && cy - change > tty->rlower) ||
2480 		    (change > 0 && cy - change < tty->rupper)) {
2481 			    if (tty_term_has(term, TTYC_VPA)) {
2482 				    tty_putcode_i(tty, TTYC_VPA, cy);
2483 				    goto out;
2484 			    }
2485 		} else if (change > 0 && tty_term_has(term, TTYC_CUU)) {
2486 			tty_putcode_i(tty, TTYC_CUU, change);
2487 			goto out;
2488 		} else if (change < 0 && tty_term_has(term, TTYC_CUD)) {
2489 			tty_putcode_i(tty, TTYC_CUD, -change);
2490 			goto out;
2491 		}
2492 	}
2493 
2494 absolute:
2495 	/* Absolute movement. */
2496 	tty_putcode_ii(tty, TTYC_CUP, cy, cx);
2497 
2498 out:
2499 	tty->cx = cx;
2500 	tty->cy = cy;
2501 }
2502 
2503 static void
2504 tty_hyperlink(struct tty *tty, const struct grid_cell *gc,
2505     struct hyperlinks *hl)
2506 {
2507 	const char	*uri, *id;
2508 
2509 	if (gc->link == tty->cell.link)
2510 		return;
2511 	tty->cell.link = gc->link;
2512 
2513 	if (hl == NULL)
2514 		return;
2515 
2516 	if (gc->link == 0 || !hyperlinks_get(hl, gc->link, &uri, NULL, &id))
2517 		tty_putcode_ss(tty, TTYC_HLS, "", "");
2518 	else
2519 		tty_putcode_ss(tty, TTYC_HLS, id, uri);
2520 }
2521 
2522 void
2523 tty_attributes(struct tty *tty, const struct grid_cell *gc,
2524     const struct grid_cell *defaults, struct colour_palette *palette,
2525     struct hyperlinks *hl)
2526 {
2527 	struct grid_cell	*tc = &tty->cell, gc2;
2528 	int			 changed;
2529 
2530 	/* Copy cell and update default colours. */
2531 	memcpy(&gc2, gc, sizeof gc2);
2532 	if (~gc->flags & GRID_FLAG_NOPALETTE) {
2533 		if (gc2.fg == 8)
2534 			gc2.fg = defaults->fg;
2535 		if (gc2.bg == 8)
2536 			gc2.bg = defaults->bg;
2537 	}
2538 
2539 	/* Ignore cell if it is the same as the last one. */
2540 	if (gc2.attr == tty->last_cell.attr &&
2541 	    gc2.fg == tty->last_cell.fg &&
2542 	    gc2.bg == tty->last_cell.bg &&
2543 	    gc2.us == tty->last_cell.us &&
2544 		gc2.link == tty->last_cell.link)
2545 		return;
2546 
2547 	/*
2548 	 * If no setab, try to use the reverse attribute as a best-effort for a
2549 	 * non-default background. This is a bit of a hack but it doesn't do
2550 	 * any serious harm and makes a couple of applications happier.
2551 	 */
2552 	if (!tty_term_has(tty->term, TTYC_SETAB)) {
2553 		if (gc2.attr & GRID_ATTR_REVERSE) {
2554 			if (gc2.fg != 7 && !COLOUR_DEFAULT(gc2.fg))
2555 				gc2.attr &= ~GRID_ATTR_REVERSE;
2556 		} else {
2557 			if (gc2.bg != 0 && !COLOUR_DEFAULT(gc2.bg))
2558 				gc2.attr |= GRID_ATTR_REVERSE;
2559 		}
2560 	}
2561 
2562 	/* Fix up the colours if necessary. */
2563 	tty_check_fg(tty, palette, &gc2);
2564 	tty_check_bg(tty, palette, &gc2);
2565 	tty_check_us(tty, palette, &gc2);
2566 
2567 	/*
2568 	 * If any bits are being cleared or the underline colour is now default,
2569 	 * reset everything.
2570 	 */
2571 	if ((tc->attr & ~gc2.attr) || (tc->us != gc2.us && gc2.us == 0))
2572 		tty_reset(tty);
2573 
2574 	/*
2575 	 * Set the colours. This may call tty_reset() (so it comes next) and
2576 	 * may add to (NOT remove) the desired attributes.
2577 	 */
2578 	tty_colours(tty, &gc2);
2579 
2580 	/* Filter out attribute bits already set. */
2581 	changed = gc2.attr & ~tc->attr;
2582 	tc->attr = gc2.attr;
2583 
2584 	/* Set the attributes. */
2585 	if (changed & GRID_ATTR_BRIGHT)
2586 		tty_putcode(tty, TTYC_BOLD);
2587 	if (changed & GRID_ATTR_DIM)
2588 		tty_putcode(tty, TTYC_DIM);
2589 	if (changed & GRID_ATTR_ITALICS)
2590 		tty_set_italics(tty);
2591 	if (changed & GRID_ATTR_ALL_UNDERSCORE) {
2592 		if ((changed & GRID_ATTR_UNDERSCORE) ||
2593 		    !tty_term_has(tty->term, TTYC_SMULX))
2594 			tty_putcode(tty, TTYC_SMUL);
2595 		else if (changed & GRID_ATTR_UNDERSCORE_2)
2596 			tty_putcode_i(tty, TTYC_SMULX, 2);
2597 		else if (changed & GRID_ATTR_UNDERSCORE_3)
2598 			tty_putcode_i(tty, TTYC_SMULX, 3);
2599 		else if (changed & GRID_ATTR_UNDERSCORE_4)
2600 			tty_putcode_i(tty, TTYC_SMULX, 4);
2601 		else if (changed & GRID_ATTR_UNDERSCORE_5)
2602 			tty_putcode_i(tty, TTYC_SMULX, 5);
2603 	}
2604 	if (changed & GRID_ATTR_BLINK)
2605 		tty_putcode(tty, TTYC_BLINK);
2606 	if (changed & GRID_ATTR_REVERSE) {
2607 		if (tty_term_has(tty->term, TTYC_REV))
2608 			tty_putcode(tty, TTYC_REV);
2609 		else if (tty_term_has(tty->term, TTYC_SMSO))
2610 			tty_putcode(tty, TTYC_SMSO);
2611 	}
2612 	if (changed & GRID_ATTR_HIDDEN)
2613 		tty_putcode(tty, TTYC_INVIS);
2614 	if (changed & GRID_ATTR_STRIKETHROUGH)
2615 		tty_putcode(tty, TTYC_SMXX);
2616 	if (changed & GRID_ATTR_OVERLINE)
2617 		tty_putcode(tty, TTYC_SMOL);
2618 	if ((changed & GRID_ATTR_CHARSET) && tty_acs_needed(tty))
2619 		tty_putcode(tty, TTYC_SMACS);
2620 
2621 	/* Set hyperlink if any. */
2622 	tty_hyperlink(tty, gc, hl);
2623 
2624 	memcpy(&tty->last_cell, &gc2, sizeof tty->last_cell);
2625 }
2626 
2627 static void
2628 tty_colours(struct tty *tty, const struct grid_cell *gc)
2629 {
2630 	struct grid_cell	*tc = &tty->cell;
2631 	int			 have_ax;
2632 
2633 	/* No changes? Nothing is necessary. */
2634 	if (gc->fg == tc->fg && gc->bg == tc->bg && gc->us == tc->us)
2635 		return;
2636 
2637 	/*
2638 	 * Is either the default colour? This is handled specially because the
2639 	 * best solution might be to reset both colours to default, in which
2640 	 * case if only one is default need to fall onward to set the other
2641 	 * colour.
2642 	 */
2643 	if (COLOUR_DEFAULT(gc->fg) || COLOUR_DEFAULT(gc->bg)) {
2644 		/*
2645 		 * If don't have AX but do have op, send sgr0 (op can't
2646 		 * actually be used because it is sometimes the same as sgr0
2647 		 * and sometimes isn't). This resets both colours to default.
2648 		 *
2649 		 * Otherwise, try to set the default colour only as needed.
2650 		 */
2651 		have_ax = tty_term_flag(tty->term, TTYC_AX);
2652 		if (!have_ax && tty_term_has(tty->term, TTYC_OP))
2653 			tty_reset(tty);
2654 		else {
2655 			if (COLOUR_DEFAULT(gc->fg) && !COLOUR_DEFAULT(tc->fg)) {
2656 				if (have_ax)
2657 					tty_puts(tty, "\033[39m");
2658 				else if (tc->fg != 7)
2659 					tty_putcode_i(tty, TTYC_SETAF, 7);
2660 				tc->fg = gc->fg;
2661 			}
2662 			if (COLOUR_DEFAULT(gc->bg) && !COLOUR_DEFAULT(tc->bg)) {
2663 				if (have_ax)
2664 					tty_puts(tty, "\033[49m");
2665 				else if (tc->bg != 0)
2666 					tty_putcode_i(tty, TTYC_SETAB, 0);
2667 				tc->bg = gc->bg;
2668 			}
2669 		}
2670 	}
2671 
2672 	/* Set the foreground colour. */
2673 	if (!COLOUR_DEFAULT(gc->fg) && gc->fg != tc->fg)
2674 		tty_colours_fg(tty, gc);
2675 
2676 	/*
2677 	 * Set the background colour. This must come after the foreground as
2678 	 * tty_colour_fg() can call tty_reset().
2679 	 */
2680 	if (!COLOUR_DEFAULT(gc->bg) && gc->bg != tc->bg)
2681 		tty_colours_bg(tty, gc);
2682 
2683 	/* Set the underscore colour. */
2684 	if (gc->us != tc->us)
2685 		tty_colours_us(tty, gc);
2686 }
2687 
2688 static void
2689 tty_check_fg(struct tty *tty, struct colour_palette *palette,
2690     struct grid_cell *gc)
2691 {
2692 	u_char	r, g, b;
2693 	u_int	colours;
2694 	int	c;
2695 
2696 	/*
2697 	 * Perform substitution if this pane has a palette. If the bright
2698 	 * attribute is set and Nobr is not present, use the bright entry in
2699 	 * the palette by changing to the aixterm colour
2700 	 */
2701 	if (~gc->flags & GRID_FLAG_NOPALETTE) {
2702 		c = gc->fg;
2703 		if (c < 8 &&
2704 		    gc->attr & GRID_ATTR_BRIGHT &&
2705 		    !tty_term_has(tty->term, TTYC_NOBR))
2706 			c += 90;
2707 		if ((c = colour_palette_get(palette, c)) != -1)
2708 			gc->fg = c;
2709 	}
2710 
2711 	/* Is this a 24-bit colour? */
2712 	if (gc->fg & COLOUR_FLAG_RGB) {
2713 		/* Not a 24-bit terminal? Translate to 256-colour palette. */
2714 		if (tty->term->flags & TERM_RGBCOLOURS)
2715 			return;
2716 		colour_split_rgb(gc->fg, &r, &g, &b);
2717 		gc->fg = colour_find_rgb(r, g, b);
2718 	}
2719 
2720 	/* How many colours does this terminal have? */
2721 	if (tty->term->flags & TERM_256COLOURS)
2722 		colours = 256;
2723 	else
2724 		colours = tty_term_number(tty->term, TTYC_COLORS);
2725 
2726 	/* Is this a 256-colour colour? */
2727 	if (gc->fg & COLOUR_FLAG_256) {
2728 		/* And not a 256 colour mode? */
2729 		if (colours < 256) {
2730 			gc->fg = colour_256to16(gc->fg);
2731 			if (gc->fg & 8) {
2732 				gc->fg &= 7;
2733 				if (colours >= 16)
2734 					gc->fg += 90;
2735 			}
2736 		}
2737 		return;
2738 	}
2739 
2740 	/* Is this an aixterm colour? */
2741 	if (gc->fg >= 90 && gc->fg <= 97 && colours < 16) {
2742 		gc->fg -= 90;
2743 		gc->attr |= GRID_ATTR_BRIGHT;
2744 	}
2745 }
2746 
2747 static void
2748 tty_check_bg(struct tty *tty, struct colour_palette *palette,
2749     struct grid_cell *gc)
2750 {
2751 	u_char	r, g, b;
2752 	u_int	colours;
2753 	int	c;
2754 
2755 	/* Perform substitution if this pane has a palette. */
2756 	if (~gc->flags & GRID_FLAG_NOPALETTE) {
2757 		if ((c = colour_palette_get(palette, gc->bg)) != -1)
2758 			gc->bg = c;
2759 	}
2760 
2761 	/* Is this a 24-bit colour? */
2762 	if (gc->bg & COLOUR_FLAG_RGB) {
2763 		/* Not a 24-bit terminal? Translate to 256-colour palette. */
2764 		if (tty->term->flags & TERM_RGBCOLOURS)
2765 			return;
2766 		colour_split_rgb(gc->bg, &r, &g, &b);
2767 		gc->bg = colour_find_rgb(r, g, b);
2768 	}
2769 
2770 	/* How many colours does this terminal have? */
2771 	if (tty->term->flags & TERM_256COLOURS)
2772 		colours = 256;
2773 	else
2774 		colours = tty_term_number(tty->term, TTYC_COLORS);
2775 
2776 	/* Is this a 256-colour colour? */
2777 	if (gc->bg & COLOUR_FLAG_256) {
2778 		/*
2779 		 * And not a 256 colour mode? Translate to 16-colour
2780 		 * palette. Bold background doesn't exist portably, so just
2781 		 * discard the bold bit if set.
2782 		 */
2783 		if (colours < 256) {
2784 			gc->bg = colour_256to16(gc->bg);
2785 			if (gc->bg & 8) {
2786 				gc->bg &= 7;
2787 				if (colours >= 16)
2788 					gc->bg += 90;
2789 			}
2790 		}
2791 		return;
2792 	}
2793 
2794 	/* Is this an aixterm colour? */
2795 	if (gc->bg >= 90 && gc->bg <= 97 && colours < 16)
2796 		gc->bg -= 90;
2797 }
2798 
2799 static void
2800 tty_check_us(__unused struct tty *tty, struct colour_palette *palette,
2801     struct grid_cell *gc)
2802 {
2803 	int	c;
2804 
2805 	/* Perform substitution if this pane has a palette. */
2806 	if (~gc->flags & GRID_FLAG_NOPALETTE) {
2807 		if ((c = colour_palette_get(palette, gc->us)) != -1)
2808 			gc->us = c;
2809 	}
2810 
2811 	/* Underscore colour is set as RGB so convert a 256 colour to RGB. */
2812 	if (gc->us & COLOUR_FLAG_256)
2813 		gc->us = colour_256toRGB (gc->us);
2814 }
2815 
2816 static void
2817 tty_colours_fg(struct tty *tty, const struct grid_cell *gc)
2818 {
2819 	struct grid_cell	*tc = &tty->cell;
2820 	char			 s[32];
2821 
2822 	/* Is this a 24-bit or 256-colour colour? */
2823 	if (gc->fg & COLOUR_FLAG_RGB || gc->fg & COLOUR_FLAG_256) {
2824 		if (tty_try_colour(tty, gc->fg, "38") == 0)
2825 			goto save;
2826 		/* Should not get here, already converted in tty_check_fg. */
2827 		return;
2828 	}
2829 
2830 	/* Is this an aixterm bright colour? */
2831 	if (gc->fg >= 90 && gc->fg <= 97) {
2832 		if (tty->term->flags & TERM_256COLOURS) {
2833 			xsnprintf(s, sizeof s, "\033[%dm", gc->fg);
2834 			tty_puts(tty, s);
2835 		} else
2836 			tty_putcode_i(tty, TTYC_SETAF, gc->fg - 90 + 8);
2837 		goto save;
2838 	}
2839 
2840 	/* Otherwise set the foreground colour. */
2841 	tty_putcode_i(tty, TTYC_SETAF, gc->fg);
2842 
2843 save:
2844 	/* Save the new values in the terminal current cell. */
2845 	tc->fg = gc->fg;
2846 }
2847 
2848 static void
2849 tty_colours_bg(struct tty *tty, const struct grid_cell *gc)
2850 {
2851 	struct grid_cell	*tc = &tty->cell;
2852 	char			 s[32];
2853 
2854 	/* Is this a 24-bit or 256-colour colour? */
2855 	if (gc->bg & COLOUR_FLAG_RGB || gc->bg & COLOUR_FLAG_256) {
2856 		if (tty_try_colour(tty, gc->bg, "48") == 0)
2857 			goto save;
2858 		/* Should not get here, already converted in tty_check_bg. */
2859 		return;
2860 	}
2861 
2862 	/* Is this an aixterm bright colour? */
2863 	if (gc->bg >= 90 && gc->bg <= 97) {
2864 		if (tty->term->flags & TERM_256COLOURS) {
2865 			xsnprintf(s, sizeof s, "\033[%dm", gc->bg + 10);
2866 			tty_puts(tty, s);
2867 		} else
2868 			tty_putcode_i(tty, TTYC_SETAB, gc->bg - 90 + 8);
2869 		goto save;
2870 	}
2871 
2872 	/* Otherwise set the background colour. */
2873 	tty_putcode_i(tty, TTYC_SETAB, gc->bg);
2874 
2875 save:
2876 	/* Save the new values in the terminal current cell. */
2877 	tc->bg = gc->bg;
2878 }
2879 
2880 static void
2881 tty_colours_us(struct tty *tty, const struct grid_cell *gc)
2882 {
2883 	struct grid_cell	*tc = &tty->cell;
2884 	u_int			 c;
2885 	u_char			 r, g, b;
2886 
2887 	/* Clear underline colour. */
2888 	if (gc->us == 0) {
2889 		tty_putcode(tty, TTYC_OL);
2890 		goto save;
2891 	}
2892 
2893 	/* Must be an RGB colour - this should never happen. */
2894 	if (~gc->us & COLOUR_FLAG_RGB)
2895 		return;
2896 
2897 	/*
2898 	 * Setulc and setal follows the ncurses(3) one argument "direct colour"
2899 	 * capability format. Calculate the colour value.
2900 	 */
2901 	colour_split_rgb(gc->us, &r, &g, &b);
2902 	c = (65536 * r) + (256 * g) + b;
2903 
2904 	/*
2905 	 * Write the colour. Only use setal if the RGB flag is set because the
2906 	 * non-RGB version may be wrong.
2907 	 */
2908 	if (tty_term_has(tty->term, TTYC_SETULC))
2909 		tty_putcode_i(tty, TTYC_SETULC, c);
2910 	else if (tty_term_has(tty->term, TTYC_SETAL) &&
2911 	    tty_term_has(tty->term, TTYC_RGB))
2912 		tty_putcode_i(tty, TTYC_SETAL, c);
2913 
2914 save:
2915 	/* Save the new values in the terminal current cell. */
2916 	tc->us = gc->us;
2917 }
2918 
2919 static int
2920 tty_try_colour(struct tty *tty, int colour, const char *type)
2921 {
2922 	u_char	r, g, b;
2923 
2924 	if (colour & COLOUR_FLAG_256) {
2925 		if (*type == '3' && tty_term_has(tty->term, TTYC_SETAF))
2926 			tty_putcode_i(tty, TTYC_SETAF, colour & 0xff);
2927 		else if (tty_term_has(tty->term, TTYC_SETAB))
2928 			tty_putcode_i(tty, TTYC_SETAB, colour & 0xff);
2929 		return (0);
2930 	}
2931 
2932 	if (colour & COLOUR_FLAG_RGB) {
2933 		colour_split_rgb(colour & 0xffffff, &r, &g, &b);
2934 		if (*type == '3' && tty_term_has(tty->term, TTYC_SETRGBF))
2935 			tty_putcode_iii(tty, TTYC_SETRGBF, r, g, b);
2936 		else if (tty_term_has(tty->term, TTYC_SETRGBB))
2937 			tty_putcode_iii(tty, TTYC_SETRGBB, r, g, b);
2938 		return (0);
2939 	}
2940 
2941 	return (-1);
2942 }
2943 
2944 static void
2945 tty_window_default_style(struct grid_cell *gc, struct window_pane *wp)
2946 {
2947 	memcpy(gc, &grid_default_cell, sizeof *gc);
2948 	gc->fg = wp->palette.fg;
2949 	gc->bg = wp->palette.bg;
2950 }
2951 
2952 void
2953 tty_default_colours(struct grid_cell *gc, struct window_pane *wp)
2954 {
2955 	struct options		*oo = wp->options;
2956 	struct format_tree	*ft;
2957 
2958 	memcpy(gc, &grid_default_cell, sizeof *gc);
2959 
2960 	if (wp->flags & PANE_STYLECHANGED) {
2961 		log_debug("%%%u: style changed", wp->id);
2962 		wp->flags &= ~PANE_STYLECHANGED;
2963 
2964 		ft = format_create(NULL, NULL, FORMAT_PANE|wp->id,
2965 		    FORMAT_NOJOBS);
2966 		format_defaults(ft, NULL, NULL, NULL, wp);
2967 		tty_window_default_style(&wp->cached_active_gc, wp);
2968 		style_add(&wp->cached_active_gc, oo, "window-active-style", ft);
2969 		tty_window_default_style(&wp->cached_gc, wp);
2970 		style_add(&wp->cached_gc, oo, "window-style", ft);
2971 		format_free(ft);
2972 	}
2973 
2974 	if (gc->fg == 8) {
2975 		if (wp == wp->window->active && wp->cached_active_gc.fg != 8)
2976 			gc->fg = wp->cached_active_gc.fg;
2977 		else
2978 			gc->fg = wp->cached_gc.fg;
2979 	}
2980 
2981 	if (gc->bg == 8) {
2982 		if (wp == wp->window->active && wp->cached_active_gc.bg != 8)
2983 			gc->bg = wp->cached_active_gc.bg;
2984 		else
2985 			gc->bg = wp->cached_gc.bg;
2986 	}
2987 }
2988 
2989 static void
2990 tty_default_attributes(struct tty *tty, const struct grid_cell *defaults,
2991     struct colour_palette *palette, u_int bg, struct hyperlinks *hl)
2992 {
2993 	struct grid_cell	gc;
2994 
2995 	memcpy(&gc, &grid_default_cell, sizeof gc);
2996 	gc.bg = bg;
2997 	tty_attributes(tty, &gc, defaults, palette, hl);
2998 }
2999 
3000 static void
3001 tty_clipboard_query_callback(__unused int fd, __unused short events, void *data)
3002 {
3003 	struct tty	*tty = data;
3004 	struct client	*c = tty->client;
3005 
3006 	c->flags &= ~CLIENT_CLIPBOARDBUFFER;
3007 	free(c->clipboard_panes);
3008 	c->clipboard_panes = NULL;
3009 	c->clipboard_npanes = 0;
3010 
3011 	tty->flags &= ~TTY_OSC52QUERY;
3012 }
3013 
3014 void
3015 tty_clipboard_query(struct tty *tty)
3016 {
3017 	struct timeval	 tv = { .tv_sec = TTY_QUERY_TIMEOUT };
3018 
3019 	if ((~tty->flags & TTY_STARTED) || (tty->flags & TTY_OSC52QUERY))
3020 		return;
3021 	tty_putcode_ss(tty, TTYC_MS, "", "?");
3022 
3023 	tty->flags |= TTY_OSC52QUERY;
3024 	evtimer_set(&tty->clipboard_timer, tty_clipboard_query_callback, tty);
3025 	evtimer_add(&tty->clipboard_timer, &tv);
3026 }
3027