[dragonfly.git] / usr.bin / window / wwupdate.c

/*	@(#)wwupdate.c	8.1 (Berkeley) 6/6/93	*/
/*	$NetBSD: wwupdate.c,v 1.6 2003/08/07 11:17:46 agc Exp $	*/

/*
 * Copyright (c) 1983, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Edward Wang at The University of California, Berkeley.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include "ww.h"
#include "tt.h"
#include "xx.h"

void
wwupdate1(int top, int bot)
{
	int i;
	int j;
	char *touched;
	struct ww_update *upd;
	char check_clreos = 0;
	int scan_top, scan_bot;

	wwnupdate++;
	{
		char *t1 = wwtouched + top, *t2 = wwtouched + bot;
		int n;

		while (!*t1++)
			if (t1 == t2)
				return;
		while (!*--t2)
			;
		scan_top = top = t1 - wwtouched - 1;
		scan_bot = bot = t2 - wwtouched + 1;
		if (scan_bot - scan_top > 1 &&
		    (tt.tt_clreos != 0 || tt.tt_clear != 0)) {
			int st = tt.tt_clreos != 0 ? scan_top : 0;

			/*
			 * t1 is one past the first touched row,
			 * t2 is on the last touched row.
			 */
			for (t1--, n = 1; t1 < t2;)
				if (*t1++)
					n++;
			/*
			 * If we can't clreos then we try for clearing
			 * the whole screen.
			 */
			if ((check_clreos = n * 10 > (wwnrow - st) * 9)) {
				scan_top = st;
				scan_bot = wwnrow;
			}
		}
	}
	if (tt.tt_clreol == 0 && !check_clreos)
		goto simple;
	for (i = scan_top, touched = &wwtouched[i], upd = &wwupd[i];
	     i < scan_bot;
	     i++, touched++, upd++) {
		int gain = 0;
		int best_gain = 0;
		int best_col = 0;
		union ww_char *ns, *os;

		if (wwinterrupt())
			return;
		if (!check_clreos && !*touched)
			continue;
		wwnupdscan++;
		j = wwncol;
		ns = &wwns[i][j];
		os = &wwos[i][j];
		while (--j >= 0) {
			/*
			 * The cost of clearing is:
			 *	ncol - nblank + X
			 * The cost of straight update is, more or less:
			 *	ncol - nsame
			 * We clear if  nblank - nsame > X
			 * X is the clreol overhead.
			 * So we make gain = nblank - nsame.
			 */
			if ((--ns)->c_w == (--os)->c_w)
				gain--;
			else
				best_gain--;
			if (ns->c_w == ' ')
				gain++;
			if (gain > best_gain) {
				best_col = j;
				best_gain = gain;
			}
		}
		upd->best_gain = best_gain;
		upd->best_col = best_col;
		upd->gain = gain;
	}
	if (check_clreos) {
		struct ww_update *u;
		int gain = 0;
		int best_gain = 0;
		int best_row = 0;
		int simple_gain = 0;
		char didit = 0;

		/*
		 * gain is the advantage of clearing all the lines.
		 * best_gain is the advantage of clearing to eos
		 * at best_row and u->best_col.
		 * simple_gain is the advantage of using only clreol.
		 * We use g > best_gain because u->best_col can be
		 * undefined when u->best_gain is 0 so we can't use it.
		 */
		for (j = scan_bot - 1, u = wwupd + j; j >= top; j--, u--) {
			int g = gain + u->best_gain;

			if (g > best_gain) {
				best_gain = g;
				best_row = j;
			}
			gain += u->gain;
			if (tt.tt_clreol != 0 && u->best_gain > 4)
				simple_gain += u->best_gain - 4;
		}
		if (tt.tt_clreos == 0) {
			if (gain > simple_gain && gain > 4) {
				xxclear();
				i = top = scan_top;
				bot = scan_bot;
				j = 0;
				didit = 1;
			}
		} else
			if (best_gain > simple_gain && best_gain > 4) {
				i = best_row;
				xxclreos(i, j = wwupd[i].best_col);
				bot = scan_bot;
				didit = 1;
			}
		if (didit) {
			wwnupdclreos++;
			wwnupdclreosline += wwnrow - i;
			u = wwupd + i;
			while (i < scan_bot) {
				union ww_char *os = &wwos[i][j];

				for (j = wwncol - j; --j >= 0;)
					os++->c_w = ' ';
				wwtouched[i++] |= WWU_TOUCHED;
				u++->best_gain = 0;
				j = 0;
			}
		} else
			wwnupdclreosmiss++;
	}
simple:
	for (i = top, touched = &wwtouched[i], upd = &wwupd[i]; i < bot;
	     i++, touched++, upd++) {
		union ww_char *os, *ns;
		char didit;

		if (!*touched)
			continue;
		*touched = 0;
		wwnupdline++;
		didit = 0;
		if (tt.tt_clreol != 0 && upd->best_gain > 4) {
			wwnupdclreol++;
			xxclreol(i, j = upd->best_col);
			for (os = &wwos[i][j], j = wwncol - j; --j >= 0;)
				os++->c_w = ' ';
			didit = 1;
		}
		ns = wwns[i];
		os = wwos[i];
		for (j = 0; j < wwncol;) {
			char *p, *q;
			char m;
			int c;
			int n;
			char buf[512];			/* > wwncol */
			union ww_char lastc;

			for (; j++ < wwncol && ns++->c_w == os++->c_w;)
				;
			if (j > wwncol)
				break;
			p = buf;
			m = ns[-1].c_m;
			c = j - 1;
			os[-1] = ns[-1];
			*p++ = ns[-1].c_c;
			n = 5;
			q = p;
			while (j < wwncol && ns->c_m == m) {
				*p++ = ns->c_c;
				if (ns->c_w == os->c_w) {
					if (--n <= 0)
						break;
					os++;
					ns++;
				} else {
					n = 5;
					q = p;
					lastc = *os;
					*os++ = *ns++;
				}
				j++;
			}
			n = q - buf;
			if (!wwwrap || i != wwnrow - 1 || c + n != wwncol)
				xxwrite(i, c, buf, n, m);
			else if (tt.tt_inschar || tt.tt_insspace) {
				if (n > 1) {
					q[-2] = q[-1];
					n--;
				} else
					c--;
				xxwrite(i, c, buf, n, m);
				c += n - 1;
				if (tt.tt_inschar)
					xxinschar(i, c, ns[-2].c_c,
						ns[-2].c_m);
				else {
					xxinsspace(i, c);
					xxwrite(i, c, &ns[-2].c_c, 1,
						ns[-2].c_m);
				}
			} else {
				if (--n)
					xxwrite(i, c, buf, n, m);
				os[-1] = lastc;
				*touched = WWU_TOUCHED;
			}
			didit = 1;
		}
		if (!didit)
			wwnupdmiss++;
	}
}
Commit	Line	Data
2c872e05	1	/* @(#)wwupdate.c 8.1 (Berkeley) 6/6/93 */
abecab39 SW	2	/* $NetBSD: wwupdate.c,v 1.6 2003/08/07 11:17:46 agc Exp $ */
abecab39 SW	3
984263bc MD	4	/*
	5	* Copyright (c) 1983, 1993
	6	* The Regents of the University of California. All rights reserved.
	7	*
	8	* This code is derived from software contributed to Berkeley by
	9	* Edward Wang at The University of California, Berkeley.
	10	*
	11	* Redistribution and use in source and binary forms, with or without
	12	* modification, are permitted provided that the following conditions
	13	* are met:
	14	* 1. Redistributions of source code must retain the above copyright
	15	* notice, this list of conditions and the following disclaimer.
	16	* 2. Redistributions in binary form must reproduce the above copyright
	17	* notice, this list of conditions and the following disclaimer in the
	18	* documentation and/or other materials provided with the distribution.
abecab39	19	* 3. Neither the name of the University nor the names of its contributors
984263bc MD	20	* may be used to endorse or promote products derived from this software
	21	* without specific prior written permission.
	22	*
	23	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	24	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	25	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	26	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	27	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	28	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	29	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	30	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	31	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	32	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	33	* SUCH DAMAGE.
	34	*/
	35
984263bc MD	36	#include "ww.h"
984263bc MD	37	#include "tt.h"
abecab39	38	#include "xx.h"
984263bc	39
abecab39 SW	40	void
abecab39 SW	41	wwupdate1(int top, int bot)
984263bc MD	42	{
984263bc MD	43	int i;
abecab39	44	int j;
984263bc MD	45	char *touched;
	46	struct ww_update *upd;
	47	char check_clreos = 0;
	48	int scan_top, scan_bot;
	49
	50	wwnupdate++;
	51	{
abecab39 SW	52	char t1 = wwtouched + top, t2 = wwtouched + bot;
abecab39 SW	53	int n;
984263bc MD	54
	55	while (!*t1++)
	56	if (t1 == t2)
	57	return;
	58	while (!*--t2)
	59	;
	60	scan_top = top = t1 - wwtouched - 1;
	61	scan_bot = bot = t2 - wwtouched + 1;
	62	if (scan_bot - scan_top > 1 &&
	63	(tt.tt_clreos != 0 \|\| tt.tt_clear != 0)) {
	64	int st = tt.tt_clreos != 0 ? scan_top : 0;
	65
	66	/*
	67	* t1 is one past the first touched row,
	68	* t2 is on the last touched row.
	69	*/
	70	for (t1--, n = 1; t1 < t2;)
	71	if (*t1++)
	72	n++;
	73	/*
	74	* If we can't clreos then we try for clearing
	75	* the whole screen.
	76	*/
abecab39	77	if ((check_clreos = n * 10 > (wwnrow - st) * 9)) {
984263bc MD	78	scan_top = st;
	79	scan_bot = wwnrow;
	80	}
	81	}
	82	}
	83	if (tt.tt_clreol == 0 && !check_clreos)
	84	goto simple;
	85	for (i = scan_top, touched = &wwtouched[i], upd = &wwupd[i];
	86	i < scan_bot;
	87	i++, touched++, upd++) {
abecab39 SW	88	int gain = 0;
	89	int best_gain = 0;
	90	int best_col = 0;
	91	union ww_char ns, os;
984263bc MD	92
	93	if (wwinterrupt())
	94	return;
	95	if (!check_clreos && !*touched)
	96	continue;
	97	wwnupdscan++;
	98	j = wwncol;
	99	ns = &wwns[i][j];
	100	os = &wwos[i][j];
	101	while (--j >= 0) {
	102	/*
	103	* The cost of clearing is:
	104	* ncol - nblank + X
	105	* The cost of straight update is, more or less:
	106	* ncol - nsame
	107	* We clear if nblank - nsame > X
	108	* X is the clreol overhead.
	109	* So we make gain = nblank - nsame.
	110	*/
	111	if ((--ns)->c_w == (--os)->c_w)
	112	gain--;
	113	else
	114	best_gain--;
	115	if (ns->c_w == ' ')
	116	gain++;
	117	if (gain > best_gain) {
	118	best_col = j;
	119	best_gain = gain;
	120	}
	121	}
	122	upd->best_gain = best_gain;
	123	upd->best_col = best_col;
	124	upd->gain = gain;
	125	}
	126	if (check_clreos) {
abecab39 SW	127	struct ww_update *u;
	128	int gain = 0;
	129	int best_gain = 0;
	130	int best_row = 0;
	131	int simple_gain = 0;
984263bc MD	132	char didit = 0;
	133
	134	/*
	135	* gain is the advantage of clearing all the lines.
	136	* best_gain is the advantage of clearing to eos
	137	* at best_row and u->best_col.
	138	* simple_gain is the advantage of using only clreol.
	139	* We use g > best_gain because u->best_col can be
	140	* undefined when u->best_gain is 0 so we can't use it.
	141	*/
	142	for (j = scan_bot - 1, u = wwupd + j; j >= top; j--, u--) {
abecab39	143	int g = gain + u->best_gain;
984263bc MD	144
	145	if (g > best_gain) {
	146	best_gain = g;
	147	best_row = j;
	148	}
	149	gain += u->gain;
	150	if (tt.tt_clreol != 0 && u->best_gain > 4)
	151	simple_gain += u->best_gain - 4;
	152	}
	153	if (tt.tt_clreos == 0) {
	154	if (gain > simple_gain && gain > 4) {
	155	xxclear();
	156	i = top = scan_top;
	157	bot = scan_bot;
	158	j = 0;
	159	didit = 1;
	160	}
	161	} else
	162	if (best_gain > simple_gain && best_gain > 4) {
	163	i = best_row;
	164	xxclreos(i, j = wwupd[i].best_col);
	165	bot = scan_bot;
	166	didit = 1;
	167	}
	168	if (didit) {
	169	wwnupdclreos++;
	170	wwnupdclreosline += wwnrow - i;
	171	u = wwupd + i;
	172	while (i < scan_bot) {
abecab39	173	union ww_char *os = &wwos[i][j];
984263bc MD	174
	175	for (j = wwncol - j; --j >= 0;)
	176	os++->c_w = ' ';
	177	wwtouched[i++] \|= WWU_TOUCHED;
	178	u++->best_gain = 0;
	179	j = 0;
	180	}
	181	} else
	182	wwnupdclreosmiss++;
	183	}
	184	simple:
	185	for (i = top, touched = &wwtouched[i], upd = &wwupd[i]; i < bot;
	186	i++, touched++, upd++) {
abecab39	187	union ww_char os, ns;
984263bc MD	188	char didit;
	189
	190	if (!*touched)
	191	continue;
	192	*touched = 0;
	193	wwnupdline++;
	194	didit = 0;
	195	if (tt.tt_clreol != 0 && upd->best_gain > 4) {
	196	wwnupdclreol++;
	197	xxclreol(i, j = upd->best_col);
	198	for (os = &wwos[i][j], j = wwncol - j; --j >= 0;)
	199	os++->c_w = ' ';
	200	didit = 1;
	201	}
	202	ns = wwns[i];
	203	os = wwos[i];
	204	for (j = 0; j < wwncol;) {
abecab39	205	char p, q;
984263bc MD	206	char m;
984263bc MD	207	int c;
abecab39	208	int n;
984263bc MD	209	char buf[512]; /* > wwncol */
	210	union ww_char lastc;
	211
	212	for (; j++ < wwncol && ns++->c_w == os++->c_w;)
	213	;
	214	if (j > wwncol)
	215	break;
	216	p = buf;
	217	m = ns[-1].c_m;
	218	c = j - 1;
	219	os[-1] = ns[-1];
	220	*p++ = ns[-1].c_c;
	221	n = 5;
	222	q = p;
	223	while (j < wwncol && ns->c_m == m) {
	224	*p++ = ns->c_c;
	225	if (ns->c_w == os->c_w) {
	226	if (--n <= 0)
	227	break;
	228	os++;
	229	ns++;
	230	} else {
	231	n = 5;
	232	q = p;
	233	lastc = *os;
	234	os++ = ns++;
	235	}
	236	j++;
	237	}
	238	n = q - buf;
	239	if (!wwwrap \|\| i != wwnrow - 1 \|\| c + n != wwncol)
	240	xxwrite(i, c, buf, n, m);
	241	else if (tt.tt_inschar \|\| tt.tt_insspace) {
	242	if (n > 1) {
	243	q[-2] = q[-1];
	244	n--;
	245	} else
	246	c--;
	247	xxwrite(i, c, buf, n, m);
	248	c += n - 1;
	249	if (tt.tt_inschar)
	250	xxinschar(i, c, ns[-2].c_c,
	251	ns[-2].c_m);
	252	else {
	253	xxinsspace(i, c);
	254	xxwrite(i, c, &ns[-2].c_c, 1,
	255	ns[-2].c_m);
	256	}
	257	} else {
	258	if (--n)
	259	xxwrite(i, c, buf, n, m);
	260	os[-1] = lastc;
	261	*touched = WWU_TOUCHED;
	262	}
	263	didit = 1;
	264	}
	265	if (!didit)
	266	wwnupdmiss++;
	267	}
	268	}