xref: /freebsd/sys/dev/vt/vt_buf.c (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2009, 2013 The FreeBSD Foundation
5  *
6  * This software was developed by Ed Schouten under sponsorship from the
7  * FreeBSD Foundation.
8  *
9  * Portions of this software were developed by Oleksandr Rybalko
10  * under sponsorship from the FreeBSD Foundation.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/kernel.h>
37 #include <sys/lock.h>
38 #include <sys/malloc.h>
39 #include <sys/mutex.h>
40 #include <sys/reboot.h>
41 
42 #include <dev/vt/vt.h>
43 
44 static MALLOC_DEFINE(M_VTBUF, "vtbuf", "vt buffer");
45 
46 #define	VTBUF_LOCK(vb)		mtx_lock_spin(&(vb)->vb_lock)
47 #define	VTBUF_UNLOCK(vb)	mtx_unlock_spin(&(vb)->vb_lock)
48 
49 #define POS_INDEX(c, r) (((r) << 12) + (c))
50 #define	POS_COPY(d, s)	do {	\
51 	(d).tp_col = (s).tp_col;	\
52 	(d).tp_row = (s).tp_row;	\
53 } while (0)
54 
55 #ifndef SC_NO_CUTPASTE
56 static int vtbuf_htw(const struct vt_buf *vb, int row);
57 static int vtbuf_wth(const struct vt_buf *vb, int row);
58 static int vtbuf_in_this_range(int begin, int test, int end, int sz);
59 #endif
60 
61 /*
62  * line4
63  * line5 <--- curroffset (terminal output to that line)
64  * line0
65  * line1                  <--- roffset (history display from that point)
66  * line2
67  * line3
68  */
69 int
70 vthistory_seek(struct vt_buf *vb, int offset, int whence)
71 {
72 	int diff, top, bottom, roffset;
73 
74 	/* No scrolling if not enabled. */
75 	if ((vb->vb_flags & VBF_SCROLL) == 0) {
76 		if (vb->vb_roffset != vb->vb_curroffset) {
77 			vb->vb_roffset = vb->vb_curroffset;
78 			return (0xffff);
79 		}
80 		return (0); /* No changes */
81 	}
82 
83 	/* "top" may be a negative integer. */
84 	bottom = vb->vb_curroffset;
85 	top = (vb->vb_flags & VBF_HISTORY_FULL) ?
86 	    bottom + vb->vb_scr_size.tp_row - vb->vb_history_size :
87 	    0;
88 
89 	roffset = 0; /* Make gcc happy. */
90 	switch (whence) {
91 	case VHS_SET:
92 		if (offset < 0)
93 			offset = 0;
94 		roffset = top + offset;
95 		break;
96 	case VHS_CUR:
97 		/*
98 		 * Operate on copy of offset value, since it temporary
99 		 * can be bigger than amount of rows in buffer.
100 		 */
101 		roffset = vb->vb_roffset;
102 		if (roffset >= bottom + vb->vb_scr_size.tp_row)
103 			roffset -= vb->vb_history_size;
104 
105 		roffset += offset;
106 		roffset = MAX(roffset, top);
107 		roffset = MIN(roffset, bottom);
108 
109 		if (roffset < 0)
110 			roffset = vb->vb_history_size + roffset;
111 
112 		break;
113 	case VHS_END:
114 		/* Go to current offset. */
115 		roffset = vb->vb_curroffset;
116 		break;
117 	}
118 
119 	diff = vb->vb_roffset != roffset;
120 	vb->vb_roffset = roffset;
121 
122 	return (diff);
123 }
124 
125 void
126 vthistory_addlines(struct vt_buf *vb, int offset)
127 {
128 #ifndef SC_NO_CUTPASTE
129 	int cur, sz;
130 #endif
131 
132 	vb->vb_curroffset += offset;
133 	if (vb->vb_curroffset + vb->vb_scr_size.tp_row >= vb->vb_history_size) {
134 		vb->vb_flags |= VBF_HISTORY_FULL;
135 		vb->vb_curroffset %= vb->vb_history_size;
136 	}
137 	if ((vb->vb_flags & VBF_SCROLL) == 0) {
138 		vb->vb_roffset = vb->vb_curroffset;
139 	}
140 
141 #ifndef SC_NO_CUTPASTE
142 	sz = vb->vb_history_size;
143 	cur = vb->vb_roffset + vb->vb_scr_size.tp_row + sz - 1;
144 	if (vtbuf_in_this_range(cur, vb->vb_mark_start.tp_row, cur + offset, sz) ||
145 	    vtbuf_in_this_range(cur, vb->vb_mark_end.tp_row, cur + offset, sz)) {
146 		/* clear screen selection */
147 		vb->vb_mark_start.tp_row = vb->vb_mark_end.tp_row;
148 		vb->vb_mark_start.tp_col = vb->vb_mark_end.tp_col;
149 	}
150 #endif
151 }
152 
153 void
154 vthistory_getpos(const struct vt_buf *vb, unsigned int *offset)
155 {
156 
157 	*offset = vb->vb_roffset;
158 }
159 
160 #ifndef SC_NO_CUTPASTE	/* Only mouse support use it now. */
161 /* Translate history row to current view row number. */
162 static int
163 vtbuf_htw(const struct vt_buf *vb, int row)
164 {
165 
166 	/*
167 	 * total 1000 rows.
168 	 * History offset	roffset	winrow
169 	 *	205		200	((205 - 200 + 1000) % 1000) = 5
170 	 *	90		990	((90 - 990 + 1000) % 1000) = 100
171 	 */
172 	return ((row - vb->vb_roffset + vb->vb_history_size) %
173 	    vb->vb_history_size);
174 }
175 
176 /* Translate current view row number to history row. */
177 static int
178 vtbuf_wth(const struct vt_buf *vb, int row)
179 {
180 
181 	return ((vb->vb_roffset + row) % vb->vb_history_size);
182 }
183 
184 /*
185  * Test if an index in a circular buffer is within a range.
186  *
187  * begin - start index
188  * end - end index
189  * test - test index
190  * sz - size of circular buffer when it turns over
191  */
192 static int
193 vtbuf_in_this_range(int begin, int test, int end, int sz)
194 {
195 
196 	begin %= sz;
197 	end %= sz;
198 
199 	/* check for inversion */
200 	if (begin > end)
201 		return (test >= begin || test < end);
202 	else
203 		return (test >= begin && test < end);
204 }
205 #endif
206 
207 int
208 vtbuf_iscursor(const struct vt_buf *vb, int row, int col)
209 {
210 #ifndef SC_NO_CUTPASTE
211 	int sc, sr, sz, ec, er, tmp;
212 #endif
213 
214 	if ((vb->vb_flags & (VBF_CURSOR|VBF_SCROLL)) == VBF_CURSOR &&
215 	    (vb->vb_cursor.tp_row == row) && (vb->vb_cursor.tp_col == col))
216 		return (1);
217 
218 #ifndef SC_NO_CUTPASTE
219 	/* Mark cut/paste region. */
220 	if (vb->vb_mark_start.tp_col == vb->vb_mark_end.tp_col &&
221 	    vb->vb_mark_start.tp_row == vb->vb_mark_end.tp_row)
222 		return (0);
223 
224 	sc = vb->vb_mark_start.tp_col;
225 	sr = vb->vb_mark_start.tp_row;
226 	ec = vb->vb_mark_end.tp_col;
227 	er = vb->vb_mark_end.tp_row;
228 
229 	/*
230 	 * Information about if the selection was made bottom-top or
231 	 * top-bottom is lost due to modulo arithmetics and needs to
232 	 * be recovered:
233 	 */
234 	sz = vb->vb_history_size;
235 	tmp = (sz + er - sr) % sz;
236 	row = vtbuf_wth(vb, row);
237 
238 	/* Swap start and end if start > end */
239 	if ((2 * tmp) > sz || (tmp == 0 && sc > ec)) {
240 		tmp = sc; sc = ec; ec = tmp;
241 		tmp = sr; sr = er; er = tmp;
242 	}
243 
244 	if (vtbuf_in_this_range(POS_INDEX(sc, sr), POS_INDEX(col, row),
245 	    POS_INDEX(ec, er), POS_INDEX(0, sz)))
246 		return (1);
247 #endif
248 
249 	return (0);
250 }
251 
252 void
253 vtbuf_lock(struct vt_buf *vb)
254 {
255 
256 	VTBUF_LOCK(vb);
257 }
258 
259 void
260 vtbuf_unlock(struct vt_buf *vb)
261 {
262 
263 	VTBUF_UNLOCK(vb);
264 }
265 
266 void
267 vtbuf_dirty(struct vt_buf *vb, const term_rect_t *area)
268 {
269 
270 	if (vb->vb_dirtyrect.tr_begin.tp_row > area->tr_begin.tp_row)
271 		vb->vb_dirtyrect.tr_begin.tp_row = area->tr_begin.tp_row;
272 	if (vb->vb_dirtyrect.tr_begin.tp_col > area->tr_begin.tp_col)
273 		vb->vb_dirtyrect.tr_begin.tp_col = area->tr_begin.tp_col;
274 	if (vb->vb_dirtyrect.tr_end.tp_row < area->tr_end.tp_row)
275 		vb->vb_dirtyrect.tr_end.tp_row = area->tr_end.tp_row;
276 	if (vb->vb_dirtyrect.tr_end.tp_col < area->tr_end.tp_col)
277 		vb->vb_dirtyrect.tr_end.tp_col = area->tr_end.tp_col;
278 }
279 
280 static inline void
281 vtbuf_dirty_cell(struct vt_buf *vb, const term_pos_t *p)
282 {
283 	term_rect_t area;
284 
285 	area.tr_begin = *p;
286 	area.tr_end.tp_row = p->tp_row + 1;
287 	area.tr_end.tp_col = p->tp_col + 1;
288 	vtbuf_dirty(vb, &area);
289 }
290 
291 static void
292 vtbuf_make_undirty(struct vt_buf *vb)
293 {
294 
295 	vb->vb_dirtyrect.tr_begin = vb->vb_scr_size;
296 	vb->vb_dirtyrect.tr_end.tp_row = vb->vb_dirtyrect.tr_end.tp_col = 0;
297 }
298 
299 void
300 vtbuf_undirty(struct vt_buf *vb, term_rect_t *r)
301 {
302 
303 	*r = vb->vb_dirtyrect;
304 	vtbuf_make_undirty(vb);
305 }
306 
307 void
308 vtbuf_copy(struct vt_buf *vb, const term_rect_t *r, const term_pos_t *p2)
309 {
310 	const term_pos_t *p1 = &r->tr_begin;
311 	term_rect_t area;
312 	unsigned int rows, cols;
313 	int pr, rdiff;
314 
315 	KASSERT(r->tr_begin.tp_row < vb->vb_scr_size.tp_row,
316 	    ("vtbuf_copy begin.tp_row %d must be less than screen width %d",
317 		r->tr_begin.tp_row, vb->vb_scr_size.tp_row));
318 	KASSERT(r->tr_begin.tp_col < vb->vb_scr_size.tp_col,
319 	    ("vtbuf_copy begin.tp_col %d must be less than screen height %d",
320 		r->tr_begin.tp_col, vb->vb_scr_size.tp_col));
321 
322 	KASSERT(r->tr_end.tp_row <= vb->vb_scr_size.tp_row,
323 	    ("vtbuf_copy end.tp_row %d must be less than screen width %d",
324 		r->tr_end.tp_row, vb->vb_scr_size.tp_row));
325 	KASSERT(r->tr_end.tp_col <= vb->vb_scr_size.tp_col,
326 	    ("vtbuf_copy end.tp_col %d must be less than screen height %d",
327 		r->tr_end.tp_col, vb->vb_scr_size.tp_col));
328 
329 	KASSERT(p2->tp_row < vb->vb_scr_size.tp_row,
330 	    ("vtbuf_copy tp_row %d must be less than screen width %d",
331 		p2->tp_row, vb->vb_scr_size.tp_row));
332 	KASSERT(p2->tp_col < vb->vb_scr_size.tp_col,
333 	    ("vtbuf_copy tp_col %d must be less than screen height %d",
334 		p2->tp_col, vb->vb_scr_size.tp_col));
335 
336 	rows = r->tr_end.tp_row - r->tr_begin.tp_row;
337 	rdiff = r->tr_begin.tp_row - p2->tp_row;
338 	cols = r->tr_end.tp_col - r->tr_begin.tp_col;
339 	if (r->tr_begin.tp_row > p2->tp_row && r->tr_begin.tp_col == 0 &&
340 	    r->tr_end.tp_col == vb->vb_scr_size.tp_col && /* Full row. */
341 	    (rows + rdiff) == vb->vb_scr_size.tp_row && /* Whole screen. */
342 	    rdiff > 0) { /* Only forward direction. Do not eat history. */
343 		vthistory_addlines(vb, rdiff);
344 	} else if (p2->tp_row < p1->tp_row) {
345 		/* Handle overlapping copies of line segments. */
346 		/* Move data up. */
347 		for (pr = 0; pr < rows; pr++)
348 			memmove(
349 			    &VTBUF_FIELD(vb, p2->tp_row + pr, p2->tp_col),
350 			    &VTBUF_FIELD(vb, p1->tp_row + pr, p1->tp_col),
351 			    cols * sizeof(term_char_t));
352 	} else {
353 		/* Move data down. */
354 		for (pr = rows - 1; pr >= 0; pr--)
355 			memmove(
356 			    &VTBUF_FIELD(vb, p2->tp_row + pr, p2->tp_col),
357 			    &VTBUF_FIELD(vb, p1->tp_row + pr, p1->tp_col),
358 			    cols * sizeof(term_char_t));
359 	}
360 
361 	area.tr_begin = *p2;
362 	area.tr_end.tp_row = MIN(p2->tp_row + rows, vb->vb_scr_size.tp_row);
363 	area.tr_end.tp_col = MIN(p2->tp_col + cols, vb->vb_scr_size.tp_col);
364 	vtbuf_dirty(vb, &area);
365 }
366 
367 static void
368 vtbuf_do_fill(struct vt_buf *vb, const term_rect_t *r, term_char_t c)
369 {
370 	unsigned int pr, pc;
371 	term_char_t *row;
372 
373 	for (pr = r->tr_begin.tp_row; pr < r->tr_end.tp_row; pr++) {
374 		row = vb->vb_rows[(vb->vb_curroffset + pr) %
375 		    VTBUF_MAX_HEIGHT(vb)];
376 		for (pc = r->tr_begin.tp_col; pc < r->tr_end.tp_col; pc++) {
377 			row[pc] = c;
378 		}
379 	}
380 }
381 
382 void
383 vtbuf_fill(struct vt_buf *vb, const term_rect_t *r, term_char_t c)
384 {
385 
386 	KASSERT(r->tr_begin.tp_row < vb->vb_scr_size.tp_row,
387 	    ("vtbuf_fill begin.tp_row %d must be < screen height %d",
388 		r->tr_begin.tp_row, vb->vb_scr_size.tp_row));
389 	KASSERT(r->tr_begin.tp_col < vb->vb_scr_size.tp_col,
390 	    ("vtbuf_fill begin.tp_col %d must be < screen width %d",
391 		r->tr_begin.tp_col, vb->vb_scr_size.tp_col));
392 
393 	KASSERT(r->tr_end.tp_row <= vb->vb_scr_size.tp_row,
394 	    ("vtbuf_fill end.tp_row %d must be <= screen height %d",
395 		r->tr_end.tp_row, vb->vb_scr_size.tp_row));
396 	KASSERT(r->tr_end.tp_col <= vb->vb_scr_size.tp_col,
397 	    ("vtbuf_fill end.tp_col %d must be <= screen width %d",
398 		r->tr_end.tp_col, vb->vb_scr_size.tp_col));
399 
400 	vtbuf_do_fill(vb, r, c);
401 	vtbuf_dirty(vb, r);
402 }
403 
404 static void
405 vtbuf_init_rows(struct vt_buf *vb)
406 {
407 	int r;
408 
409 	vb->vb_history_size = MAX(vb->vb_history_size, vb->vb_scr_size.tp_row);
410 
411 	for (r = 0; r < vb->vb_history_size; r++)
412 		vb->vb_rows[r] = &vb->vb_buffer[r * vb->vb_scr_size.tp_col];
413 }
414 
415 static void
416 vtbuf_do_clearhistory(struct vt_buf *vb)
417 {
418 	term_rect_t rect;
419 	const teken_attr_t *a;
420 	term_char_t ch;
421 
422 	a = teken_get_curattr(&vb->vb_terminal->tm_emulator);
423 	ch = TCOLOR_FG(a->ta_fgcolor) | TCOLOR_BG(a->ta_bgcolor);
424 
425 	rect.tr_begin.tp_row = rect.tr_begin.tp_col = 0;
426 	rect.tr_end.tp_col = vb->vb_scr_size.tp_col;
427 	rect.tr_end.tp_row = vb->vb_history_size;
428 
429 	vtbuf_do_fill(vb, &rect, VTBUF_SPACE_CHAR(ch));
430 }
431 
432 static void
433 vtbuf_reset_scrollback(struct vt_buf *vb)
434 {
435 	vb->vb_roffset = 0;
436 	vb->vb_curroffset = 0;
437 	vb->vb_mark_start.tp_row = 0;
438 	vb->vb_mark_start.tp_col = 0;
439 	vb->vb_mark_end.tp_row = 0;
440 	vb->vb_mark_end.tp_col = 0;
441 }
442 
443 void
444 vtbuf_init_early(struct vt_buf *vb)
445 {
446 	vb->vb_flags |= VBF_CURSOR;
447 	vtbuf_reset_scrollback(vb);
448 	vtbuf_init_rows(vb);
449 	vtbuf_do_clearhistory(vb);
450 	vtbuf_make_undirty(vb);
451 	if ((vb->vb_flags & VBF_MTX_INIT) == 0) {
452 		mtx_init(&vb->vb_lock, "vtbuf", NULL, MTX_SPIN);
453 		vb->vb_flags |= VBF_MTX_INIT;
454 	}
455 }
456 
457 void
458 vtbuf_init(struct vt_buf *vb, const term_pos_t *p)
459 {
460 	int sz;
461 
462 	vb->vb_scr_size = *p;
463 	vb->vb_history_size = VBF_DEFAULT_HISTORY_SIZE;
464 
465 	if ((vb->vb_flags & VBF_STATIC) == 0) {
466 		sz = vb->vb_history_size * p->tp_col * sizeof(term_char_t);
467 		vb->vb_buffer = malloc(sz, M_VTBUF, M_WAITOK | M_ZERO);
468 
469 		sz = vb->vb_history_size * sizeof(term_char_t *);
470 		vb->vb_rows = malloc(sz, M_VTBUF, M_WAITOK | M_ZERO);
471 	}
472 
473 	vtbuf_init_early(vb);
474 }
475 
476 void
477 vtbuf_clearhistory(struct vt_buf *vb)
478 {
479 	VTBUF_LOCK(vb);
480 	vtbuf_do_clearhistory(vb);
481 	vtbuf_reset_scrollback(vb);
482 	vb->vb_flags &= ~VBF_HISTORY_FULL;
483 	VTBUF_UNLOCK(vb);
484 }
485 
486 void
487 vtbuf_sethistory_size(struct vt_buf *vb, unsigned int size)
488 {
489 	term_pos_t p;
490 
491 	/* With same size */
492 	p.tp_row = vb->vb_scr_size.tp_row;
493 	p.tp_col = vb->vb_scr_size.tp_col;
494 	vtbuf_grow(vb, &p, size);
495 }
496 
497 void
498 vtbuf_grow(struct vt_buf *vb, const term_pos_t *p, unsigned int history_size)
499 {
500 	term_char_t *old, *new, **rows, **oldrows, **copyrows, *row, *oldrow;
501 	unsigned int w, h, c, r, old_history_size;
502 	size_t bufsize, rowssize;
503 	int history_full;
504 	const teken_attr_t *a;
505 	term_char_t ch;
506 
507 	a = teken_get_curattr(&vb->vb_terminal->tm_emulator);
508 	ch = TCOLOR_FG(a->ta_fgcolor) | TCOLOR_BG(a->ta_bgcolor);
509 
510 	history_size = MAX(history_size, p->tp_row);
511 
512 	/* Allocate new buffer. */
513 	bufsize = history_size * p->tp_col * sizeof(term_char_t);
514 	new = malloc(bufsize, M_VTBUF, M_WAITOK | M_ZERO);
515 	rowssize = history_size * sizeof(term_pos_t *);
516 	rows = malloc(rowssize, M_VTBUF, M_WAITOK | M_ZERO);
517 
518 	/* Toggle it. */
519 	VTBUF_LOCK(vb);
520 	old = vb->vb_flags & VBF_STATIC ? NULL : vb->vb_buffer;
521 	oldrows = vb->vb_flags & VBF_STATIC ? NULL : vb->vb_rows;
522 	copyrows = vb->vb_rows;
523 
524 	w = vb->vb_scr_size.tp_col;
525 	h = vb->vb_scr_size.tp_row;
526 	old_history_size = vb->vb_history_size;
527 	history_full = vb->vb_flags & VBF_HISTORY_FULL ||
528 	    vb->vb_curroffset + h >= history_size;
529 
530 	vb->vb_history_size = history_size;
531 	vb->vb_buffer = new;
532 	vb->vb_rows = rows;
533 	vb->vb_flags &= ~VBF_STATIC;
534 	vb->vb_scr_size = *p;
535 	vtbuf_init_rows(vb);
536 
537 	/*
538 	 * Copy rows to the new buffer. The first row in the history
539 	 * is back to index 0, ie. the new buffer doesn't cycle.
540 	 */
541 	if (history_size > old_history_size) {
542 		for (r = 0; r < old_history_size; r++) {
543 			row = rows[r];
544 
545 			/* Compute the corresponding row in the old buffer. */
546 			if (history_full)
547 				/*
548 				 * The buffer is full, the "top" row is
549 				 * the one just after the viewable area
550 				 * (curroffset + viewable height) in the
551 				 * cycling buffer. The corresponding row
552 				 * is computed from this top row.
553 				 */
554 				oldrow = copyrows[
555 				    (vb->vb_curroffset + h + r) %
556 				    old_history_size];
557 			else
558 				/*
559 				 * The buffer is not full, therefore,
560 				 * we didn't cycle already. The
561 				 * corresponding rows are the same in
562 				 * both buffers.
563 				 */
564 				oldrow = copyrows[r];
565 
566 			memmove(row, oldrow,
567 			    MIN(p->tp_col, w) * sizeof(term_char_t));
568 
569 			/*
570 			 * XXX VTBUF_SPACE_CHAR(TERMINAL_NORM_ATTR) will
571 			 * extended lines of kernel text using the wrong
572 			 * background color.
573 			 */
574 			for (c = MIN(p->tp_col, w); c < p->tp_col; c++) {
575 				row[c] = VTBUF_SPACE_CHAR(ch);
576 			}
577 		}
578 
579 		/* Fill remaining rows. */
580 		for (r = old_history_size; r < history_size; r++) {
581 			row = rows[r];
582 			for (c = MIN(p->tp_col, w); c < p->tp_col; c++) {
583 				row[c] = VTBUF_SPACE_CHAR(ch);
584 			}
585 		}
586 
587 		vb->vb_flags &= ~VBF_HISTORY_FULL;
588 
589 		/*
590 		 * If the screen is already filled (there are non-visible lines
591 		 * above the current viewable area), adjust curroffset to the
592 		 * new viewable area.
593 		 *
594 		 * If the old buffer was full, set curroffset to the
595 		 * <h>th most recent line of history in the new, non-cycled
596 		 * buffer. Otherwise, it didn't cycle, so the old curroffset
597 		 * is the same in the new buffer.
598 		 */
599 		if (history_full)
600 			vb->vb_curroffset = old_history_size - h;
601 	} else {
602 		/*
603 		 * (old_history_size - history_size) lines of history are
604 		 * dropped.
605 		 */
606 		for (r = 0; r < history_size; r++) {
607 			row = rows[r];
608 
609 			/*
610 			 * Compute the corresponding row in the old buffer.
611 			 *
612 			 * See the equivalent if{} block above for an
613 			 * explanation.
614 			 */
615 			if (history_full)
616 				oldrow = copyrows[
617 				    (vb->vb_curroffset + h + r +
618 				     (old_history_size - history_size)) %
619 				    old_history_size];
620 			else
621 				oldrow = copyrows[r];
622 
623 			memmove(row, oldrow,
624 			    MIN(p->tp_col, w) * sizeof(term_char_t));
625 
626 			/*
627 			 * XXX VTBUF_SPACE_CHAR(TERMINAL_NORM_ATTR) will
628 			 * extended lines of kernel text using the wrong
629 			 * background color.
630 			 */
631 			for (c = MIN(p->tp_col, w); c < p->tp_col; c++) {
632 				row[c] = VTBUF_SPACE_CHAR(ch);
633 			}
634 		}
635 
636 		if (history_full) {
637 			vb->vb_curroffset = history_size - h;
638 			vb->vb_flags |= VBF_HISTORY_FULL;
639 		}
640 	}
641 
642 	vb->vb_roffset = vb->vb_curroffset;
643 
644 	/* Adjust cursor position. */
645 	if (vb->vb_cursor.tp_col > p->tp_col - 1)
646 		/*
647 		 * Move cursor to the last column, in case its previous
648 		 * position is outside of the new screen area.
649 		 */
650 		vb->vb_cursor.tp_col = p->tp_col - 1;
651 
652 	if (vb->vb_curroffset > 0 || vb->vb_cursor.tp_row > p->tp_row - 1)
653 		/* Move cursor to the last line on the screen. */
654 		vb->vb_cursor.tp_row = p->tp_row - 1;
655 
656 	VTBUF_UNLOCK(vb);
657 
658 	/* Deallocate old buffer. */
659 	free(old, M_VTBUF);
660 	free(oldrows, M_VTBUF);
661 }
662 
663 void
664 vtbuf_putchar(struct vt_buf *vb, const term_pos_t *p, term_char_t c)
665 {
666 	term_char_t *row;
667 
668 	KASSERT(p->tp_row < vb->vb_scr_size.tp_row,
669 	    ("vtbuf_putchar tp_row %d must be less than screen width %d",
670 		p->tp_row, vb->vb_scr_size.tp_row));
671 	KASSERT(p->tp_col < vb->vb_scr_size.tp_col,
672 	    ("vtbuf_putchar tp_col %d must be less than screen height %d",
673 		p->tp_col, vb->vb_scr_size.tp_col));
674 
675 	row = vb->vb_rows[(vb->vb_curroffset + p->tp_row) %
676 	    VTBUF_MAX_HEIGHT(vb)];
677 	if (row[p->tp_col] != c) {
678 		row[p->tp_col] = c;
679 		vtbuf_dirty_cell(vb, p);
680 	}
681 }
682 
683 void
684 vtbuf_cursor_position(struct vt_buf *vb, const term_pos_t *p)
685 {
686 	if (vb->vb_flags & VBF_CURSOR) {
687 		vtbuf_dirty_cell(vb, &vb->vb_cursor);
688 		vb->vb_cursor = *p;
689 		vtbuf_dirty_cell(vb, &vb->vb_cursor);
690 	} else {
691 		vb->vb_cursor = *p;
692 	}
693 }
694 
695 #ifndef SC_NO_CUTPASTE
696 static void
697 vtbuf_flush_mark(struct vt_buf *vb)
698 {
699 	term_rect_t area;
700 	int s, e;
701 
702 	/* Notify renderer to update marked region. */
703 	if ((vb->vb_mark_start.tp_col != vb->vb_mark_end.tp_col) ||
704 	    (vb->vb_mark_start.tp_row != vb->vb_mark_end.tp_row)) {
705 		s = vtbuf_htw(vb, vb->vb_mark_start.tp_row);
706 		e = vtbuf_htw(vb, vb->vb_mark_end.tp_row);
707 
708 		area.tr_begin.tp_col = 0;
709 		area.tr_begin.tp_row = MIN(s, e);
710 
711 		area.tr_end.tp_col = vb->vb_scr_size.tp_col;
712 		area.tr_end.tp_row = MAX(s, e) + 1;
713 
714 		VTBUF_LOCK(vb);
715 		vtbuf_dirty(vb, &area);
716 		VTBUF_UNLOCK(vb);
717 	}
718 }
719 
720 int
721 vtbuf_get_marked_len(struct vt_buf *vb)
722 {
723 	int ei, si, sz;
724 	term_pos_t s, e;
725 
726 	/* Swap according to window coordinates. */
727 	if (POS_INDEX(vtbuf_htw(vb, vb->vb_mark_start.tp_row),
728 	    vb->vb_mark_start.tp_col) >
729 	    POS_INDEX(vtbuf_htw(vb, vb->vb_mark_end.tp_row),
730 	    vb->vb_mark_end.tp_col)) {
731 		POS_COPY(e, vb->vb_mark_start);
732 		POS_COPY(s, vb->vb_mark_end);
733 	} else {
734 		POS_COPY(s, vb->vb_mark_start);
735 		POS_COPY(e, vb->vb_mark_end);
736 	}
737 
738 	si = s.tp_row * vb->vb_scr_size.tp_col + s.tp_col;
739 	ei = e.tp_row * vb->vb_scr_size.tp_col + e.tp_col;
740 
741 	/* Number symbols and number of rows to inject \r */
742 	sz = ei - si + (1 + e.tp_row - s.tp_row);
743 
744 	return (sz * sizeof(term_char_t));
745 }
746 
747 static bool
748 tchar_is_word_separator(term_char_t ch)
749 {
750 	/* List of unicode word separator characters: */
751 	switch (TCHAR_CHARACTER(ch)) {
752 	case 0x0020: /* SPACE */
753 	case 0x180E: /* MONGOLIAN VOWEL SEPARATOR */
754 	case 0x2002: /* EN SPACE (nut) */
755 	case 0x2003: /* EM SPACE (mutton) */
756 	case 0x2004: /* THREE-PER-EM SPACE (thick space) */
757 	case 0x2005: /* FOUR-PER-EM SPACE (mid space) */
758 	case 0x2006: /* SIX-PER-EM SPACE */
759 	case 0x2008: /* PUNCTUATION SPACE */
760 	case 0x2009: /* THIN SPACE */
761 	case 0x200A: /* HAIR SPACE */
762 	case 0x200B: /* ZERO WIDTH SPACE */
763 	case 0x3000: /* IDEOGRAPHIC SPACE */
764 		return (true);
765 	default:
766 		return (false);
767 	}
768 }
769 
770 void
771 vtbuf_extract_marked(struct vt_buf *vb, term_char_t *buf, int sz, int mark)
772 {
773 	int i, j, r, c, cs, ce;
774 	term_pos_t s, e;
775 
776 	/* Swap according to window coordinates. */
777 	if (POS_INDEX(vtbuf_htw(vb, vb->vb_mark_start.tp_row),
778 	    vb->vb_mark_start.tp_col) >
779 	    POS_INDEX(vtbuf_htw(vb, vb->vb_mark_end.tp_row),
780 	    vb->vb_mark_end.tp_col)) {
781 		POS_COPY(e, vb->vb_mark_start);
782 		POS_COPY(s, vb->vb_mark_end);
783 	} else {
784 		POS_COPY(s, vb->vb_mark_start);
785 		POS_COPY(e, vb->vb_mark_end);
786 	}
787 
788 	i = 0;
789 	for (r = s.tp_row; r <= e.tp_row; r++) {
790 		cs = (r == s.tp_row)?s.tp_col:0;
791 		ce = (r == e.tp_row)?e.tp_col:vb->vb_scr_size.tp_col;
792 
793 		/* Copy characters from terminal window. */
794 		j = i;
795 		for (c = cs; c < ce; c++)
796 			buf[i++] = vb->vb_rows[r][c];
797 
798 		/* For all rows, but the last one. */
799 		if (r != e.tp_row || mark == VTB_MARK_ROW) {
800 			/* Trim trailing word separators, if any. */
801 			for (; i != j; i--) {
802 				if (!tchar_is_word_separator(buf[i - 1]))
803 					break;
804 			}
805 			/* Add newline character as expected by TTY. */
806 			buf[i++] = '\r';
807 		}
808 	}
809 	/* Zero rest of expected buffer size, if any. */
810 	while ((i * sizeof(buf[0])) < sz)
811 		buf[i++] = '\0';
812 
813 	MPASS((i * sizeof(buf[0])) == sz);
814 }
815 
816 int
817 vtbuf_set_mark(struct vt_buf *vb, int type, int col, int row)
818 {
819 	term_char_t *r;
820 	int i;
821 
822 	switch (type) {
823 	case VTB_MARK_END:	/* B1 UP */
824 		if (vb->vb_mark_last != VTB_MARK_MOVE)
825 			return (0);
826 		/* FALLTHROUGH */
827 	case VTB_MARK_MOVE:
828 	case VTB_MARK_EXTEND:
829 		vtbuf_flush_mark(vb); /* Clean old mark. */
830 		vb->vb_mark_end.tp_col = col;
831 		vb->vb_mark_end.tp_row = vtbuf_wth(vb, row);
832 		break;
833 	case VTB_MARK_START:
834 		vtbuf_flush_mark(vb); /* Clean old mark. */
835 		vb->vb_mark_start.tp_col = col;
836 		vb->vb_mark_start.tp_row = vtbuf_wth(vb, row);
837 		/* Start again, so clear end point. */
838 		vb->vb_mark_end.tp_col = col;
839 		vb->vb_mark_end.tp_row = vtbuf_wth(vb, row);
840 		break;
841 	case VTB_MARK_WORD:
842 		vtbuf_flush_mark(vb); /* Clean old mark. */
843 		vb->vb_mark_start.tp_row = vb->vb_mark_end.tp_row =
844 		    vtbuf_wth(vb, row);
845 		r = vb->vb_rows[vb->vb_mark_start.tp_row];
846 		for (i = col; i >= 0; i --) {
847 			if (tchar_is_word_separator(r[i])) {
848 				vb->vb_mark_start.tp_col = i + 1;
849 				break;
850 			}
851 		}
852 		/* No space - word extends to beginning of line. */
853 		if (i == -1)
854 			vb->vb_mark_start.tp_col = 0;
855 		for (i = col; i < vb->vb_scr_size.tp_col; i++) {
856 			if (tchar_is_word_separator(r[i])) {
857 				vb->vb_mark_end.tp_col = i;
858 				break;
859 			}
860 		}
861 		/* No space - word extends to end of line. */
862 		if (i == vb->vb_scr_size.tp_col)
863 			vb->vb_mark_end.tp_col = i;
864 
865 		if (vb->vb_mark_start.tp_col > vb->vb_mark_end.tp_col)
866 			vb->vb_mark_start.tp_col = vb->vb_mark_end.tp_col;
867 		break;
868 	case VTB_MARK_ROW:
869 		vtbuf_flush_mark(vb); /* Clean old mark. */
870 		vb->vb_mark_start.tp_col = 0;
871 		vb->vb_mark_end.tp_col = vb->vb_scr_size.tp_col;
872 		vb->vb_mark_start.tp_row = vb->vb_mark_end.tp_row =
873 		    vtbuf_wth(vb, row);
874 		break;
875 	case VTB_MARK_NONE:
876 		vb->vb_mark_last = type;
877 		/* FALLTHROUGH */
878 	default:
879 		/* panic? */
880 		return (0);
881 	}
882 
883 	vb->vb_mark_last = type;
884 	/* Draw new marked region. */
885 	vtbuf_flush_mark(vb);
886 	return (1);
887 }
888 #endif
889 
890 void
891 vtbuf_cursor_visibility(struct vt_buf *vb, int yes)
892 {
893 	int oflags, nflags;
894 
895 	oflags = vb->vb_flags;
896 	if (yes)
897 		vb->vb_flags |= VBF_CURSOR;
898 	else
899 		vb->vb_flags &= ~VBF_CURSOR;
900 	nflags = vb->vb_flags;
901 
902 	if (oflags != nflags)
903 		vtbuf_dirty_cell(vb, &vb->vb_cursor);
904 }
905 
906 void
907 vtbuf_scroll_mode(struct vt_buf *vb, int yes)
908 {
909 	int oflags, nflags;
910 
911 	VTBUF_LOCK(vb);
912 	oflags = vb->vb_flags;
913 	if (yes)
914 		vb->vb_flags |= VBF_SCROLL;
915 	else
916 		vb->vb_flags &= ~VBF_SCROLL;
917 	nflags = vb->vb_flags;
918 
919 	if (oflags != nflags)
920 		vtbuf_dirty_cell(vb, &vb->vb_cursor);
921 	VTBUF_UNLOCK(vb);
922 }
923