xref: /freebsd/sys/dev/vt/vt_buf.c (revision d15f2551b25f79ddcbe289faa95e655100b952da)
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 #define	VTBUF_LOCK_OWNED(vb)	mtx_owned(&(vb)->vb_lock)
49 
50 #define POS_INDEX(c, r) (((r) << 12) + (c))
51 #define	POS_COPY(d, s)	do {	\
52 	(d).tp_col = (s).tp_col;	\
53 	(d).tp_row = (s).tp_row;	\
54 } while (0)
55 
56 #ifndef SC_NO_CUTPASTE
57 static int vtbuf_htw(const struct vt_buf *vb, int row);
58 static int vtbuf_wth(const struct vt_buf *vb, int row);
59 static int vtbuf_in_this_range(int begin, int test, int end, int sz);
60 #endif
61 
62 /*
63  * line4
64  * line5 <--- curroffset (terminal output to that line)
65  * line0
66  * line1                  <--- roffset (history display from that point)
67  * line2
68  * line3
69  */
70 int
71 vthistory_seek(struct vt_buf *vb, int offset, int whence)
72 {
73 	int diff, top, bottom, roffset;
74 
75 	/* No scrolling if not enabled. */
76 	if ((vb->vb_flags & VBF_SCROLL) == 0) {
77 		if (vb->vb_roffset != vb->vb_curroffset) {
78 			vb->vb_roffset = vb->vb_curroffset;
79 			return (0xffff);
80 		}
81 		return (0); /* No changes */
82 	}
83 
84 	/* "top" may be a negative integer. */
85 	bottom = vb->vb_curroffset;
86 	top = (vb->vb_flags & VBF_HISTORY_FULL) ?
87 	    bottom + vb->vb_scr_size.tp_row - vb->vb_history_size :
88 	    0;
89 
90 	roffset = 0; /* Make gcc happy. */
91 	switch (whence) {
92 	case VHS_SET:
93 		if (offset < 0)
94 			offset = 0;
95 		roffset = top + offset;
96 		break;
97 	case VHS_CUR:
98 		/*
99 		 * Operate on copy of offset value, since it temporary
100 		 * can be bigger than amount of rows in buffer.
101 		 */
102 		roffset = vb->vb_roffset;
103 		if (roffset >= bottom + vb->vb_scr_size.tp_row)
104 			roffset -= vb->vb_history_size;
105 
106 		roffset += offset;
107 		roffset = MAX(roffset, top);
108 		roffset = MIN(roffset, bottom);
109 
110 		if (roffset < 0)
111 			roffset = vb->vb_history_size + roffset;
112 
113 		break;
114 	case VHS_END:
115 		/* Go to current offset. */
116 		roffset = vb->vb_curroffset;
117 		break;
118 	}
119 
120 	diff = vb->vb_roffset != roffset;
121 	vb->vb_roffset = roffset;
122 
123 	return (diff);
124 }
125 
126 void
127 vthistory_addlines(struct vt_buf *vb, int offset)
128 {
129 #ifndef SC_NO_CUTPASTE
130 	int cur, sz;
131 #endif
132 
133 	vb->vb_curroffset += offset;
134 	if (vb->vb_curroffset + vb->vb_scr_size.tp_row >= vb->vb_history_size) {
135 		vb->vb_flags |= VBF_HISTORY_FULL;
136 		vb->vb_curroffset %= vb->vb_history_size;
137 	}
138 	if ((vb->vb_flags & VBF_SCROLL) == 0) {
139 		vb->vb_roffset = vb->vb_curroffset;
140 	}
141 
142 #ifndef SC_NO_CUTPASTE
143 	sz = vb->vb_history_size;
144 	cur = vb->vb_roffset + vb->vb_scr_size.tp_row + sz - 1;
145 	if (vtbuf_in_this_range(cur, vb->vb_mark_start.tp_row, cur + offset, sz) ||
146 	    vtbuf_in_this_range(cur, vb->vb_mark_end.tp_row, cur + offset, sz)) {
147 		/* clear screen selection */
148 		vb->vb_mark_start.tp_row = vb->vb_mark_end.tp_row;
149 		vb->vb_mark_start.tp_col = vb->vb_mark_end.tp_col;
150 	}
151 #endif
152 }
153 
154 void
155 vthistory_getpos(const struct vt_buf *vb, unsigned int *offset)
156 {
157 
158 	*offset = vb->vb_roffset;
159 }
160 
161 #ifndef SC_NO_CUTPASTE	/* Only mouse support use it now. */
162 /* Translate history row to current view row number. */
163 static int
164 vtbuf_htw(const struct vt_buf *vb, int row)
165 {
166 
167 	/*
168 	 * total 1000 rows.
169 	 * History offset	roffset	winrow
170 	 *	205		200	((205 - 200 + 1000) % 1000) = 5
171 	 *	90		990	((90 - 990 + 1000) % 1000) = 100
172 	 */
173 	return ((row - vb->vb_roffset + vb->vb_history_size) %
174 	    vb->vb_history_size);
175 }
176 
177 /* Translate current view row number to history row. */
178 static int
179 vtbuf_wth(const struct vt_buf *vb, int row)
180 {
181 
182 	return ((vb->vb_roffset + row) % vb->vb_history_size);
183 }
184 
185 /*
186  * Test if an index in a circular buffer is within a range.
187  *
188  * begin - start index
189  * end - end index
190  * test - test index
191  * sz - size of circular buffer when it turns over
192  */
193 static int
194 vtbuf_in_this_range(int begin, int test, int end, int sz)
195 {
196 
197 	begin %= sz;
198 	end %= sz;
199 
200 	/* check for inversion */
201 	if (begin > end)
202 		return (test >= begin || test < end);
203 	else
204 		return (test >= begin && test < end);
205 }
206 
207 void
208 vtbuf_unmark(struct vt_buf *vb)
209 {
210 
211 	vtbuf_set_mark(vb, VTB_MARK_START, 0, 0);
212 }
213 
214 void
215 vtbuf_unmark_on_cross(struct vt_buf *vb, int target_begin, int target_end)
216 {
217 	int hsz, mb, me, tb, te;
218 
219 	tb = vtbuf_wth(vb, target_begin);
220 	te = vtbuf_wth(vb, target_end);
221 	mb = vb->vb_mark_start.tp_row;
222 	me = vb->vb_mark_end.tp_row;
223 	hsz = vb->vb_history_size;
224 
225 	/*
226 	 * Test intersection with vtbuf_in_this_range due to use of
227 	 * the circular buffer.
228 	 */
229 	if (vtbuf_in_this_range(tb, mb, te, hsz) ||
230 	    vtbuf_in_this_range(tb, me, te, hsz) ||
231 	    vtbuf_in_this_range(mb, tb, me, hsz) ||
232 	    vtbuf_in_this_range(mb, te, me, hsz)) {
233 		vtbuf_unmark(vb);
234 	}
235 }
236 #endif
237 
238 int
239 vtbuf_iscursor(const struct vt_buf *vb, int row, int col)
240 {
241 #ifndef SC_NO_CUTPASTE
242 	int sc, sr, sz, ec, er, tmp;
243 #endif
244 
245 	if ((vb->vb_flags & (VBF_CURSOR|VBF_SCROLL)) == VBF_CURSOR &&
246 	    (vb->vb_cursor.tp_row == row) && (vb->vb_cursor.tp_col == col))
247 		return (1);
248 
249 #ifndef SC_NO_CUTPASTE
250 	/* Mark cut/paste region. */
251 	if (vb->vb_mark_start.tp_col == vb->vb_mark_end.tp_col &&
252 	    vb->vb_mark_start.tp_row == vb->vb_mark_end.tp_row)
253 		return (0);
254 
255 	sc = vb->vb_mark_start.tp_col;
256 	sr = vb->vb_mark_start.tp_row;
257 	ec = vb->vb_mark_end.tp_col;
258 	er = vb->vb_mark_end.tp_row;
259 
260 	/*
261 	 * Information about if the selection was made bottom-top or
262 	 * top-bottom is lost due to modulo arithmetics and needs to
263 	 * be recovered:
264 	 */
265 	sz = vb->vb_history_size;
266 	tmp = (sz + er - sr) % sz;
267 	row = vtbuf_wth(vb, row);
268 
269 	/* Swap start and end if start > end */
270 	if ((2 * tmp) > sz || (tmp == 0 && sc > ec)) {
271 		tmp = sc; sc = ec; ec = tmp;
272 		tmp = sr; sr = er; er = tmp;
273 	}
274 
275 	if (vtbuf_in_this_range(POS_INDEX(sc, sr), POS_INDEX(col, row),
276 	    POS_INDEX(ec, er), POS_INDEX(0, sz)))
277 		return (1);
278 #endif
279 
280 	return (0);
281 }
282 
283 void
284 vtbuf_lock(struct vt_buf *vb)
285 {
286 
287 	VTBUF_LOCK(vb);
288 }
289 
290 void
291 vtbuf_unlock(struct vt_buf *vb)
292 {
293 
294 	VTBUF_UNLOCK(vb);
295 }
296 
297 void
298 vtbuf_dirty(struct vt_buf *vb, const term_rect_t *area)
299 {
300 
301 	if (vb->vb_dirtyrect.tr_begin.tp_row > area->tr_begin.tp_row)
302 		vb->vb_dirtyrect.tr_begin.tp_row = area->tr_begin.tp_row;
303 	if (vb->vb_dirtyrect.tr_begin.tp_col > area->tr_begin.tp_col)
304 		vb->vb_dirtyrect.tr_begin.tp_col = area->tr_begin.tp_col;
305 	if (vb->vb_dirtyrect.tr_end.tp_row < area->tr_end.tp_row)
306 		vb->vb_dirtyrect.tr_end.tp_row = area->tr_end.tp_row;
307 	if (vb->vb_dirtyrect.tr_end.tp_col < area->tr_end.tp_col)
308 		vb->vb_dirtyrect.tr_end.tp_col = area->tr_end.tp_col;
309 }
310 
311 static inline void
312 vtbuf_dirty_cell(struct vt_buf *vb, const term_pos_t *p)
313 {
314 	term_rect_t area;
315 
316 	area.tr_begin = *p;
317 	area.tr_end.tp_row = p->tp_row + 1;
318 	area.tr_end.tp_col = p->tp_col + 1;
319 	vtbuf_dirty(vb, &area);
320 }
321 
322 static void
323 vtbuf_make_undirty(struct vt_buf *vb)
324 {
325 
326 	vb->vb_dirtyrect.tr_begin = vb->vb_scr_size;
327 	vb->vb_dirtyrect.tr_end.tp_row = vb->vb_dirtyrect.tr_end.tp_col = 0;
328 }
329 
330 void
331 vtbuf_undirty(struct vt_buf *vb, term_rect_t *r)
332 {
333 
334 	*r = vb->vb_dirtyrect;
335 	vtbuf_make_undirty(vb);
336 }
337 
338 void
339 vtbuf_copy(struct vt_buf *vb, const term_rect_t *r, const term_pos_t *p2)
340 {
341 	const term_pos_t *p1 = &r->tr_begin;
342 	term_rect_t area;
343 	unsigned int rows, cols;
344 	int pr, rdiff;
345 
346 	KASSERT(r->tr_begin.tp_row < vb->vb_scr_size.tp_row,
347 	    ("vtbuf_copy begin.tp_row %d must be less than screen width %d",
348 		r->tr_begin.tp_row, vb->vb_scr_size.tp_row));
349 	KASSERT(r->tr_begin.tp_col < vb->vb_scr_size.tp_col,
350 	    ("vtbuf_copy begin.tp_col %d must be less than screen height %d",
351 		r->tr_begin.tp_col, vb->vb_scr_size.tp_col));
352 
353 	KASSERT(r->tr_end.tp_row <= vb->vb_scr_size.tp_row,
354 	    ("vtbuf_copy end.tp_row %d must be less than screen width %d",
355 		r->tr_end.tp_row, vb->vb_scr_size.tp_row));
356 	KASSERT(r->tr_end.tp_col <= vb->vb_scr_size.tp_col,
357 	    ("vtbuf_copy end.tp_col %d must be less than screen height %d",
358 		r->tr_end.tp_col, vb->vb_scr_size.tp_col));
359 
360 	KASSERT(p2->tp_row < vb->vb_scr_size.tp_row,
361 	    ("vtbuf_copy tp_row %d must be less than screen width %d",
362 		p2->tp_row, vb->vb_scr_size.tp_row));
363 	KASSERT(p2->tp_col < vb->vb_scr_size.tp_col,
364 	    ("vtbuf_copy tp_col %d must be less than screen height %d",
365 		p2->tp_col, vb->vb_scr_size.tp_col));
366 
367 	rows = r->tr_end.tp_row - r->tr_begin.tp_row;
368 	rdiff = r->tr_begin.tp_row - p2->tp_row;
369 	cols = r->tr_end.tp_col - r->tr_begin.tp_col;
370 	if (r->tr_begin.tp_row > p2->tp_row && r->tr_begin.tp_col == 0 &&
371 	    r->tr_end.tp_col == vb->vb_scr_size.tp_col && /* Full row. */
372 	    (rows + rdiff) == vb->vb_scr_size.tp_row && /* Whole screen. */
373 	    rdiff > 0) { /* Only forward direction. Do not eat history. */
374 		vthistory_addlines(vb, rdiff);
375 	} else if (p2->tp_row < p1->tp_row) {
376 		/* Handle overlapping copies of line segments. */
377 		/* Move data up. */
378 		for (pr = 0; pr < rows; pr++)
379 			memmove(
380 			    &VTBUF_FIELD(vb, p2->tp_row + pr, p2->tp_col),
381 			    &VTBUF_FIELD(vb, p1->tp_row + pr, p1->tp_col),
382 			    cols * sizeof(term_char_t));
383 	} else {
384 		/* Move data down. */
385 		for (pr = rows - 1; pr >= 0; pr--)
386 			memmove(
387 			    &VTBUF_FIELD(vb, p2->tp_row + pr, p2->tp_col),
388 			    &VTBUF_FIELD(vb, p1->tp_row + pr, p1->tp_col),
389 			    cols * sizeof(term_char_t));
390 	}
391 
392 	area.tr_begin = *p2;
393 	area.tr_end.tp_row = MIN(p2->tp_row + rows, vb->vb_scr_size.tp_row);
394 	area.tr_end.tp_col = MIN(p2->tp_col + cols, vb->vb_scr_size.tp_col);
395 	vtbuf_dirty(vb, &area);
396 }
397 
398 static void
399 vtbuf_do_fill(struct vt_buf *vb, const term_rect_t *r, term_char_t c)
400 {
401 	unsigned int pr, pc;
402 	term_char_t *row;
403 
404 	for (pr = r->tr_begin.tp_row; pr < r->tr_end.tp_row; pr++) {
405 		row = vb->vb_rows[(vb->vb_curroffset + pr) %
406 		    VTBUF_MAX_HEIGHT(vb)];
407 		for (pc = r->tr_begin.tp_col; pc < r->tr_end.tp_col; pc++) {
408 			row[pc] = c;
409 		}
410 	}
411 }
412 
413 void
414 vtbuf_fill(struct vt_buf *vb, const term_rect_t *r, term_char_t c)
415 {
416 
417 	KASSERT(r->tr_begin.tp_row < vb->vb_scr_size.tp_row,
418 	    ("vtbuf_fill begin.tp_row %d must be < screen height %d",
419 		r->tr_begin.tp_row, vb->vb_scr_size.tp_row));
420 	KASSERT(r->tr_begin.tp_col < vb->vb_scr_size.tp_col,
421 	    ("vtbuf_fill begin.tp_col %d must be < screen width %d",
422 		r->tr_begin.tp_col, vb->vb_scr_size.tp_col));
423 
424 	KASSERT(r->tr_end.tp_row <= vb->vb_scr_size.tp_row,
425 	    ("vtbuf_fill end.tp_row %d must be <= screen height %d",
426 		r->tr_end.tp_row, vb->vb_scr_size.tp_row));
427 	KASSERT(r->tr_end.tp_col <= vb->vb_scr_size.tp_col,
428 	    ("vtbuf_fill end.tp_col %d must be <= screen width %d",
429 		r->tr_end.tp_col, vb->vb_scr_size.tp_col));
430 
431 	vtbuf_do_fill(vb, r, c);
432 	vtbuf_dirty(vb, r);
433 }
434 
435 static void
436 vtbuf_init_rows(struct vt_buf *vb)
437 {
438 	int r;
439 
440 	vb->vb_history_size = MAX(vb->vb_history_size, vb->vb_scr_size.tp_row);
441 
442 	for (r = 0; r < vb->vb_history_size; r++)
443 		vb->vb_rows[r] = &vb->vb_buffer[r * vb->vb_scr_size.tp_col];
444 }
445 
446 static void
447 vtbuf_do_clearhistory(struct vt_buf *vb)
448 {
449 	term_rect_t rect;
450 	const teken_attr_t *a;
451 	term_char_t ch;
452 
453 	a = teken_get_curattr(&vb->vb_terminal->tm_emulator);
454 	ch = TCOLOR_FG(a->ta_fgcolor) | TCOLOR_BG(a->ta_bgcolor);
455 
456 	rect.tr_begin.tp_row = rect.tr_begin.tp_col = 0;
457 	rect.tr_end.tp_col = vb->vb_scr_size.tp_col;
458 	rect.tr_end.tp_row = vb->vb_history_size;
459 
460 	vtbuf_do_fill(vb, &rect, VTBUF_SPACE_CHAR(ch));
461 }
462 
463 static void
464 vtbuf_reset_scrollback(struct vt_buf *vb)
465 {
466 	vb->vb_roffset = 0;
467 	vb->vb_curroffset = 0;
468 	vb->vb_mark_start.tp_row = 0;
469 	vb->vb_mark_start.tp_col = 0;
470 	vb->vb_mark_end.tp_row = 0;
471 	vb->vb_mark_end.tp_col = 0;
472 }
473 
474 void
475 vtbuf_init_early(struct vt_buf *vb)
476 {
477 	vb->vb_flags |= VBF_CURSOR;
478 	vtbuf_reset_scrollback(vb);
479 	vtbuf_init_rows(vb);
480 	vtbuf_do_clearhistory(vb);
481 	vtbuf_make_undirty(vb);
482 	if ((vb->vb_flags & VBF_MTX_INIT) == 0) {
483 		mtx_init(&vb->vb_lock, "vtbuf", NULL, MTX_SPIN);
484 		vb->vb_flags |= VBF_MTX_INIT;
485 	}
486 }
487 
488 void
489 vtbuf_init(struct vt_buf *vb, const term_pos_t *p)
490 {
491 	int sz;
492 
493 	vb->vb_scr_size = *p;
494 	vb->vb_history_size = VBF_DEFAULT_HISTORY_SIZE;
495 
496 	if ((vb->vb_flags & VBF_STATIC) == 0) {
497 		sz = vb->vb_history_size * p->tp_col * sizeof(term_char_t);
498 		vb->vb_buffer = malloc(sz, M_VTBUF, M_WAITOK | M_ZERO);
499 
500 		sz = vb->vb_history_size * sizeof(term_char_t *);
501 		vb->vb_rows = malloc(sz, M_VTBUF, M_WAITOK | M_ZERO);
502 	}
503 
504 	vtbuf_init_early(vb);
505 }
506 
507 void
508 vtbuf_clearhistory(struct vt_buf *vb)
509 {
510 	VTBUF_LOCK(vb);
511 	vtbuf_do_clearhistory(vb);
512 	vtbuf_reset_scrollback(vb);
513 	vb->vb_flags &= ~VBF_HISTORY_FULL;
514 	VTBUF_UNLOCK(vb);
515 }
516 
517 void
518 vtbuf_sethistory_size(struct vt_buf *vb, unsigned int size)
519 {
520 	term_pos_t p;
521 
522 	/* With same size */
523 	p.tp_row = vb->vb_scr_size.tp_row;
524 	p.tp_col = vb->vb_scr_size.tp_col;
525 	vtbuf_grow(vb, &p, size);
526 }
527 
528 void
529 vtbuf_grow(struct vt_buf *vb, const term_pos_t *p, unsigned int history_size)
530 {
531 	term_char_t *old, *new, **rows, **oldrows, **copyrows, *row, *oldrow;
532 	unsigned int w, h, c, r, old_history_size;
533 	int history_full;
534 	const teken_attr_t *a;
535 	term_char_t ch;
536 
537 	a = teken_get_curattr(&vb->vb_terminal->tm_emulator);
538 	ch = TCOLOR_FG(a->ta_fgcolor) | TCOLOR_BG(a->ta_bgcolor);
539 
540 	history_size = MAX(history_size, p->tp_row);
541 
542 	/* Allocate new buffer. */
543 	new = mallocarray(history_size, p->tp_col * sizeof(term_char_t),
544 	    M_VTBUF, M_WAITOK | M_ZERO);
545 	rows = mallocarray(history_size, sizeof(term_pos_t *), M_VTBUF,
546 	    M_WAITOK | M_ZERO);
547 
548 	/* Toggle it. */
549 	VTBUF_LOCK(vb);
550 	old = vb->vb_flags & VBF_STATIC ? NULL : vb->vb_buffer;
551 	oldrows = vb->vb_flags & VBF_STATIC ? NULL : vb->vb_rows;
552 	copyrows = vb->vb_rows;
553 
554 	w = vb->vb_scr_size.tp_col;
555 	h = vb->vb_scr_size.tp_row;
556 	old_history_size = vb->vb_history_size;
557 	history_full = vb->vb_flags & VBF_HISTORY_FULL ||
558 	    vb->vb_curroffset + h >= history_size;
559 
560 	vb->vb_history_size = history_size;
561 	vb->vb_buffer = new;
562 	vb->vb_rows = rows;
563 	vb->vb_flags &= ~VBF_STATIC;
564 	vb->vb_scr_size = *p;
565 	vtbuf_init_rows(vb);
566 
567 	/*
568 	 * Copy rows to the new buffer. The first row in the history
569 	 * is back to index 0, ie. the new buffer doesn't cycle.
570 	 */
571 	if (history_size > old_history_size) {
572 		for (r = 0; r < old_history_size; r++) {
573 			row = rows[r];
574 
575 			/* Compute the corresponding row in the old buffer. */
576 			if (history_full)
577 				/*
578 				 * The buffer is full, the "top" row is
579 				 * the one just after the viewable area
580 				 * (curroffset + viewable height) in the
581 				 * cycling buffer. The corresponding row
582 				 * is computed from this top row.
583 				 */
584 				oldrow = copyrows[
585 				    (vb->vb_curroffset + h + r) %
586 				    old_history_size];
587 			else
588 				/*
589 				 * The buffer is not full, therefore,
590 				 * we didn't cycle already. The
591 				 * corresponding rows are the same in
592 				 * both buffers.
593 				 */
594 				oldrow = copyrows[r];
595 
596 			memmove(row, oldrow,
597 			    MIN(p->tp_col, w) * sizeof(term_char_t));
598 
599 			/*
600 			 * XXX VTBUF_SPACE_CHAR(TERMINAL_NORM_ATTR) will
601 			 * extended lines of kernel text using the wrong
602 			 * background color.
603 			 */
604 			for (c = MIN(p->tp_col, w); c < p->tp_col; c++) {
605 				row[c] = VTBUF_SPACE_CHAR(ch);
606 			}
607 		}
608 
609 		/* Fill remaining rows. */
610 		for (r = old_history_size; r < history_size; r++) {
611 			row = rows[r];
612 			for (c = MIN(p->tp_col, w); c < p->tp_col; c++) {
613 				row[c] = VTBUF_SPACE_CHAR(ch);
614 			}
615 		}
616 
617 		vb->vb_flags &= ~VBF_HISTORY_FULL;
618 
619 		/*
620 		 * If the screen is already filled (there are non-visible lines
621 		 * above the current viewable area), adjust curroffset to the
622 		 * new viewable area.
623 		 *
624 		 * If the old buffer was full, set curroffset to the
625 		 * <h>th most recent line of history in the new, non-cycled
626 		 * buffer. Otherwise, it didn't cycle, so the old curroffset
627 		 * is the same in the new buffer.
628 		 */
629 		if (history_full)
630 			vb->vb_curroffset = old_history_size - h;
631 	} else {
632 		/*
633 		 * (old_history_size - history_size) lines of history are
634 		 * dropped.
635 		 */
636 		for (r = 0; r < history_size; r++) {
637 			row = rows[r];
638 
639 			/*
640 			 * Compute the corresponding row in the old buffer.
641 			 *
642 			 * See the equivalent if{} block above for an
643 			 * explanation.
644 			 */
645 			if (history_full)
646 				oldrow = copyrows[
647 				    (vb->vb_curroffset + h + r +
648 				     (old_history_size - history_size)) %
649 				    old_history_size];
650 			else
651 				oldrow = copyrows[r];
652 
653 			memmove(row, oldrow,
654 			    MIN(p->tp_col, w) * sizeof(term_char_t));
655 
656 			/*
657 			 * XXX VTBUF_SPACE_CHAR(TERMINAL_NORM_ATTR) will
658 			 * extended lines of kernel text using the wrong
659 			 * background color.
660 			 */
661 			for (c = MIN(p->tp_col, w); c < p->tp_col; c++) {
662 				row[c] = VTBUF_SPACE_CHAR(ch);
663 			}
664 		}
665 
666 		if (history_full) {
667 			vb->vb_curroffset = history_size - h;
668 			vb->vb_flags |= VBF_HISTORY_FULL;
669 		}
670 	}
671 
672 	vb->vb_roffset = vb->vb_curroffset;
673 
674 	/* Adjust cursor position. */
675 	if (vb->vb_cursor.tp_col > p->tp_col - 1)
676 		/*
677 		 * Move cursor to the last column, in case its previous
678 		 * position is outside of the new screen area.
679 		 */
680 		vb->vb_cursor.tp_col = p->tp_col - 1;
681 
682 	if (vb->vb_curroffset > 0 || vb->vb_cursor.tp_row > p->tp_row - 1)
683 		/* Move cursor to the last line on the screen. */
684 		vb->vb_cursor.tp_row = p->tp_row - 1;
685 
686 	VTBUF_UNLOCK(vb);
687 
688 	/* Deallocate old buffer. */
689 	free(old, M_VTBUF);
690 	free(oldrows, M_VTBUF);
691 }
692 
693 void
694 vtbuf_putchar(struct vt_buf *vb, const term_pos_t *p, term_char_t c)
695 {
696 	term_char_t *row;
697 
698 	KASSERT(p->tp_row < vb->vb_scr_size.tp_row,
699 	    ("vtbuf_putchar tp_row %d must be less than screen width %d",
700 		p->tp_row, vb->vb_scr_size.tp_row));
701 	KASSERT(p->tp_col < vb->vb_scr_size.tp_col,
702 	    ("vtbuf_putchar tp_col %d must be less than screen height %d",
703 		p->tp_col, vb->vb_scr_size.tp_col));
704 
705 	row = vb->vb_rows[(vb->vb_curroffset + p->tp_row) %
706 	    VTBUF_MAX_HEIGHT(vb)];
707 	if (row[p->tp_col] != c) {
708 		row[p->tp_col] = c;
709 		vtbuf_dirty_cell(vb, p);
710 	}
711 }
712 
713 void
714 vtbuf_cursor_position(struct vt_buf *vb, const term_pos_t *p)
715 {
716 	if (vb->vb_flags & VBF_CURSOR) {
717 		vtbuf_dirty_cell(vb, &vb->vb_cursor);
718 		vb->vb_cursor = *p;
719 		vtbuf_dirty_cell(vb, &vb->vb_cursor);
720 	} else {
721 		vb->vb_cursor = *p;
722 	}
723 }
724 
725 #ifndef SC_NO_CUTPASTE
726 static void
727 vtbuf_flush_mark(struct vt_buf *vb)
728 {
729 	term_rect_t area;
730 	int s, e;
731 
732 	/* Notify renderer to update marked region. */
733 	if ((vb->vb_mark_start.tp_col != vb->vb_mark_end.tp_col) ||
734 	    (vb->vb_mark_start.tp_row != vb->vb_mark_end.tp_row)) {
735 		s = vtbuf_htw(vb, vb->vb_mark_start.tp_row);
736 		e = vtbuf_htw(vb, vb->vb_mark_end.tp_row);
737 
738 		area.tr_begin.tp_col = 0;
739 		area.tr_begin.tp_row = MIN(s, e);
740 
741 		area.tr_end.tp_col = vb->vb_scr_size.tp_col;
742 		area.tr_end.tp_row = MAX(s, e) + 1;
743 
744 		/*
745 		 * If the request originates from a keyboard, the vtbuf is
746 		 * locked by teken for the entire duration of the request.
747 		 * For all other sources, we avoid holding the spinlock for
748 		 * extended periods.
749 		 */
750 		if (VTBUF_LOCK_OWNED(vb)) {
751 			vtbuf_dirty(vb, &area);
752 		} else {
753 			VTBUF_LOCK(vb);
754 			vtbuf_dirty(vb, &area);
755 			VTBUF_UNLOCK(vb);
756 		}
757 	}
758 }
759 
760 int
761 vtbuf_get_marked_len(struct vt_buf *vb)
762 {
763 	int ei, si, sz;
764 	term_pos_t s, e;
765 
766 	/* Swap according to window coordinates. */
767 	if (POS_INDEX(vtbuf_htw(vb, vb->vb_mark_start.tp_row),
768 	    vb->vb_mark_start.tp_col) >
769 	    POS_INDEX(vtbuf_htw(vb, vb->vb_mark_end.tp_row),
770 	    vb->vb_mark_end.tp_col)) {
771 		POS_COPY(e, vb->vb_mark_start);
772 		POS_COPY(s, vb->vb_mark_end);
773 	} else {
774 		POS_COPY(s, vb->vb_mark_start);
775 		POS_COPY(e, vb->vb_mark_end);
776 	}
777 
778 	si = s.tp_row * vb->vb_scr_size.tp_col + s.tp_col;
779 	ei = e.tp_row * vb->vb_scr_size.tp_col + e.tp_col;
780 
781 	/* Number symbols and number of rows to inject \r */
782 	sz = ei - si + (1 + e.tp_row - s.tp_row);
783 
784 	return (sz * sizeof(term_char_t));
785 }
786 
787 static bool
788 tchar_is_word_separator(term_char_t ch)
789 {
790 	/* List of unicode word separator characters: */
791 	switch (TCHAR_CHARACTER(ch)) {
792 	case 0x0020: /* SPACE */
793 	case 0x180E: /* MONGOLIAN VOWEL SEPARATOR */
794 	case 0x2002: /* EN SPACE (nut) */
795 	case 0x2003: /* EM SPACE (mutton) */
796 	case 0x2004: /* THREE-PER-EM SPACE (thick space) */
797 	case 0x2005: /* FOUR-PER-EM SPACE (mid space) */
798 	case 0x2006: /* SIX-PER-EM SPACE */
799 	case 0x2008: /* PUNCTUATION SPACE */
800 	case 0x2009: /* THIN SPACE */
801 	case 0x200A: /* HAIR SPACE */
802 	case 0x200B: /* ZERO WIDTH SPACE */
803 	case 0x3000: /* IDEOGRAPHIC SPACE */
804 		return (true);
805 	default:
806 		return (false);
807 	}
808 }
809 
810 void
811 vtbuf_extract_marked(struct vt_buf *vb, term_char_t *buf, int sz, int mark)
812 {
813 	int i, j, r, c, cs, ce;
814 	term_pos_t s, e;
815 
816 	/* Swap according to window coordinates. */
817 	if (POS_INDEX(vtbuf_htw(vb, vb->vb_mark_start.tp_row),
818 	    vb->vb_mark_start.tp_col) >
819 	    POS_INDEX(vtbuf_htw(vb, vb->vb_mark_end.tp_row),
820 	    vb->vb_mark_end.tp_col)) {
821 		POS_COPY(e, vb->vb_mark_start);
822 		POS_COPY(s, vb->vb_mark_end);
823 	} else {
824 		POS_COPY(s, vb->vb_mark_start);
825 		POS_COPY(e, vb->vb_mark_end);
826 	}
827 
828 	i = 0;
829 	for (r = s.tp_row; r <= e.tp_row; r++) {
830 		cs = (r == s.tp_row)?s.tp_col:0;
831 		ce = (r == e.tp_row)?e.tp_col:vb->vb_scr_size.tp_col;
832 
833 		/* Copy characters from terminal window. */
834 		j = i;
835 		for (c = cs; c < ce; c++)
836 			buf[i++] = vb->vb_rows[r][c];
837 
838 		/* For all rows, but the last one. */
839 		if (r != e.tp_row || mark == VTB_MARK_ROW) {
840 			/* Trim trailing word separators, if any. */
841 			for (; i != j; i--) {
842 				if (!tchar_is_word_separator(buf[i - 1]))
843 					break;
844 			}
845 			/* Add newline character as expected by TTY. */
846 			buf[i++] = '\r';
847 		}
848 	}
849 	/* Zero rest of expected buffer size, if any. */
850 	while ((i * sizeof(buf[0])) < sz)
851 		buf[i++] = '\0';
852 
853 	MPASS((i * sizeof(buf[0])) == sz);
854 }
855 
856 int
857 vtbuf_set_mark(struct vt_buf *vb, int type, int col, int row)
858 {
859 	term_char_t *r;
860 	int i;
861 
862 	switch (type) {
863 	case VTB_MARK_END:	/* B1 UP */
864 		if (vb->vb_mark_last != VTB_MARK_MOVE)
865 			return (0);
866 		/* FALLTHROUGH */
867 	case VTB_MARK_MOVE:
868 	case VTB_MARK_EXTEND:
869 		vtbuf_flush_mark(vb); /* Clean old mark. */
870 		vb->vb_mark_end.tp_col = col;
871 		vb->vb_mark_end.tp_row = vtbuf_wth(vb, row);
872 		break;
873 	case VTB_MARK_START:
874 		vtbuf_flush_mark(vb); /* Clean old mark. */
875 		vb->vb_mark_start.tp_col = col;
876 		vb->vb_mark_start.tp_row = vtbuf_wth(vb, row);
877 		/* Start again, so clear end point. */
878 		vb->vb_mark_end.tp_col = col;
879 		vb->vb_mark_end.tp_row = vtbuf_wth(vb, row);
880 		break;
881 	case VTB_MARK_WORD:
882 		vtbuf_flush_mark(vb); /* Clean old mark. */
883 		vb->vb_mark_start.tp_row = vb->vb_mark_end.tp_row =
884 		    vtbuf_wth(vb, row);
885 		r = vb->vb_rows[vb->vb_mark_start.tp_row];
886 		for (i = col; i >= 0; i --) {
887 			if (tchar_is_word_separator(r[i])) {
888 				vb->vb_mark_start.tp_col = i + 1;
889 				break;
890 			}
891 		}
892 		/* No space - word extends to beginning of line. */
893 		if (i == -1)
894 			vb->vb_mark_start.tp_col = 0;
895 		for (i = col; i < vb->vb_scr_size.tp_col; i++) {
896 			if (tchar_is_word_separator(r[i])) {
897 				vb->vb_mark_end.tp_col = i;
898 				break;
899 			}
900 		}
901 		/* No space - word extends to end of line. */
902 		if (i == vb->vb_scr_size.tp_col)
903 			vb->vb_mark_end.tp_col = i;
904 
905 		if (vb->vb_mark_start.tp_col > vb->vb_mark_end.tp_col)
906 			vb->vb_mark_start.tp_col = vb->vb_mark_end.tp_col;
907 		break;
908 	case VTB_MARK_ROW:
909 		vtbuf_flush_mark(vb); /* Clean old mark. */
910 		vb->vb_mark_start.tp_col = 0;
911 		vb->vb_mark_end.tp_col = vb->vb_scr_size.tp_col;
912 		vb->vb_mark_start.tp_row = vb->vb_mark_end.tp_row =
913 		    vtbuf_wth(vb, row);
914 		break;
915 	case VTB_MARK_NONE:
916 		vb->vb_mark_last = type;
917 		/* FALLTHROUGH */
918 	default:
919 		/* panic? */
920 		return (0);
921 	}
922 
923 	vb->vb_mark_last = type;
924 	/* Draw new marked region. */
925 	vtbuf_flush_mark(vb);
926 	return (1);
927 }
928 #endif
929 
930 void
931 vtbuf_cursor_visibility(struct vt_buf *vb, int yes)
932 {
933 	int oflags, nflags;
934 
935 	oflags = vb->vb_flags;
936 	if (yes)
937 		vb->vb_flags |= VBF_CURSOR;
938 	else
939 		vb->vb_flags &= ~VBF_CURSOR;
940 	nflags = vb->vb_flags;
941 
942 	if (oflags != nflags)
943 		vtbuf_dirty_cell(vb, &vb->vb_cursor);
944 }
945 
946 void
947 vtbuf_scroll_mode(struct vt_buf *vb, int yes)
948 {
949 	int oflags, nflags;
950 
951 	VTBUF_LOCK(vb);
952 	oflags = vb->vb_flags;
953 	if (yes)
954 		vb->vb_flags |= VBF_SCROLL;
955 	else
956 		vb->vb_flags &= ~VBF_SCROLL;
957 	nflags = vb->vb_flags;
958 
959 	if (oflags != nflags)
960 		vtbuf_dirty_cell(vb, &vb->vb_cursor);
961 	VTBUF_UNLOCK(vb);
962 }
963