[apple/shell_cmds.git] / window / wwupdate.c

/*	$NetBSD: wwupdate.c,v 1.4 1997/11/21 08:37:59 lukem 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. 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 <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)wwupdate.c	8.1 (Berkeley) 6/6/93";
#else
__RCSID("$NetBSD: wwupdate.c,v 1.4 1997/11/21 08:37:59 lukem Exp $");
#endif
#endif /* not lint */

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

void
wwupdate1(top, bot)
	int top, 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
44bd5ea7 A	1	/* $NetBSD: wwupdate.c,v 1.4 1997/11/21 08:37:59 lukem Exp $ */
	2
	3	/*
	4	* Copyright (c) 1983, 1993
	5	* The Regents of the University of California. All rights reserved.
	6	*
	7	* This code is derived from software contributed to Berkeley by
	8	* Edward Wang at The University of California, Berkeley.
	9	*
	10	* Redistribution and use in source and binary forms, with or without
	11	* modification, are permitted provided that the following conditions
	12	* are met:
	13	* 1. Redistributions of source code must retain the above copyright
	14	* notice, this list of conditions and the following disclaimer.
	15	* 2. Redistributions in binary form must reproduce the above copyright
	16	* notice, this list of conditions and the following disclaimer in the
	17	* documentation and/or other materials provided with the distribution.
	18	* 3. All advertising materials mentioning features or use of this software
	19	* must display the following acknowledgement:
	20	* This product includes software developed by the University of
	21	* California, Berkeley and its contributors.
	22	* 4. Neither the name of the University nor the names of its contributors
	23	* may be used to endorse or promote products derived from this software
	24	* without specific prior written permission.
	25	*
	26	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	27	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	28	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	29	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	30	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	31	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	32	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	33	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	34	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	35	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	36	* SUCH DAMAGE.
	37	*/
	38
	39	#include <sys/cdefs.h>
	40	#ifndef lint
	41	#if 0
	42	static char sccsid[] = "@(#)wwupdate.c 8.1 (Berkeley) 6/6/93";
	43	#else
	44	__RCSID("$NetBSD: wwupdate.c,v 1.4 1997/11/21 08:37:59 lukem Exp $");
	45	#endif
	46	#endif /* not lint */
	47
	48	#include "ww.h"
	49	#include "tt.h"
	50	#include "xx.h"
	51
	52	void
	53	wwupdate1(top, bot)
	54	int top, bot;
	55	{
	56	int i;
	57	int j;
	58	char *touched;
	59	struct ww_update *upd;
	60	char check_clreos = 0;
	61	int scan_top, scan_bot;
	62
	63	wwnupdate++;
	64	{
65	char t1 = wwtouched + top, t2 = wwtouched + bot;
66	int n;
67
68	while (!*t1++)
69	if (t1 == t2)
70	return;
71	while (!*--t2)
72	;
73	scan_top = top = t1 - wwtouched - 1;
74	scan_bot = bot = t2 - wwtouched + 1;
75	if (scan_bot - scan_top > 1 &&
76	(tt.tt_clreos != 0 \|\| tt.tt_clear != 0)) {
77	int st = tt.tt_clreos != 0 ? scan_top : 0;
78
79	/*
80	* t1 is one past the first touched row,
81	* t2 is on the last touched row.
82	*/
83	for (t1--, n = 1; t1 < t2;)
84	if (*t1++)
85	n++;
86	/*
87	* If we can't clreos then we try for clearing
88	* the whole screen.
89	*/
90	if ((check_clreos = n * 10 > (wwnrow - st) * 9)) {
91	scan_top = st;
92	scan_bot = wwnrow;
93	}
94	}
95	}
96	if (tt.tt_clreol == 0 && !check_clreos)
97	goto simple;
98	for (i = scan_top, touched = &wwtouched[i], upd = &wwupd[i];
99	i < scan_bot;
100	i++, touched++, upd++) {
101	int gain = 0;
102	int best_gain = 0;
103	int best_col = 0;
104	union ww_char ns, os;
105
106	if (wwinterrupt())
107	return;
108	if (!check_clreos && !*touched)
109	continue;
110	wwnupdscan++;
111	j = wwncol;
112	ns = &wwns[i][j];
113	os = &wwos[i][j];
114	while (--j >= 0) {
115	/*
116	* The cost of clearing is:
117	* ncol - nblank + X
118	* The cost of straight update is, more or less:
119	* ncol - nsame
120	* We clear if nblank - nsame > X
121	* X is the clreol overhead.
122	* So we make gain = nblank - nsame.
123	*/
124	if ((--ns)->c_w == (--os)->c_w)
125	gain--;
126	else
127	best_gain--;
128	if (ns->c_w == ' ')
129	gain++;
130	if (gain > best_gain) {
131	best_col = j;
132	best_gain = gain;
133	}
134	}
135	upd->best_gain = best_gain;
136	upd->best_col = best_col;
137	upd->gain = gain;
138	}
139	if (check_clreos) {
140	struct ww_update *u;
141	int gain = 0;
142	int best_gain = 0;
143	int best_row = 0;
144	int simple_gain = 0;
145	char didit = 0;
146
147	/*
148	* gain is the advantage of clearing all the lines.
149	* best_gain is the advantage of clearing to eos
150	* at best_row and u->best_col.
151	* simple_gain is the advantage of using only clreol.
152	* We use g > best_gain because u->best_col can be
153	* undefined when u->best_gain is 0 so we can't use it.
154	*/
155	for (j = scan_bot - 1, u = wwupd + j; j >= top; j--, u--) {
156	int g = gain + u->best_gain;
157
158	if (g > best_gain) {
159	best_gain = g;
160	best_row = j;
161	}
162	gain += u->gain;
163	if (tt.tt_clreol != 0 && u->best_gain > 4)
164	simple_gain += u->best_gain - 4;
165	}
166	if (tt.tt_clreos == 0) {
167	if (gain > simple_gain && gain > 4) {
168	xxclear();
169	i = top = scan_top;
170	bot = scan_bot;
171	j = 0;
172	didit = 1;
173	}
174	} else
175	if (best_gain > simple_gain && best_gain > 4) {
176	i = best_row;
177	xxclreos(i, j = wwupd[i].best_col);
178	bot = scan_bot;
179	didit = 1;
180	}
181	if (didit) {
182	wwnupdclreos++;
183	wwnupdclreosline += wwnrow - i;
184	u = wwupd + i;
185	while (i < scan_bot) {
186	union ww_char *os = &wwos[i][j];
187
188	for (j = wwncol - j; --j >= 0;)
189	os++->c_w = ' ';
190	wwtouched[i++] \|= WWU_TOUCHED;
191	u++->best_gain = 0;
192	j = 0;
193	}
194	} else
195	wwnupdclreosmiss++;
196	}
197	simple:
198	for (i = top, touched = &wwtouched[i], upd = &wwupd[i]; i < bot;
199	i++, touched++, upd++) {
200	union ww_char os, ns;
201	char didit;
202
203	if (!*touched)
204	continue;
205	*touched = 0;
206	wwnupdline++;
207	didit = 0;
208	if (tt.tt_clreol != 0 && upd->best_gain > 4) {
209	wwnupdclreol++;
210	xxclreol(i, j = upd->best_col);
211	for (os = &wwos[i][j], j = wwncol - j; --j >= 0;)
212	os++->c_w = ' ';
213	didit = 1;
214	}
215	ns = wwns[i];
216	os = wwos[i];
217	for (j = 0; j < wwncol;) {
218	char p, q;
219	char m;
220	int c;
221	int n;
222	char buf[512]; /* > wwncol */
223	union ww_char lastc;
224
225	for (; j++ < wwncol && ns++->c_w == os++->c_w;)
226	;
227	if (j > wwncol)
228	break;
229	p = buf;
230	m = ns[-1].c_m;
231	c = j - 1;
232	os[-1] = ns[-1];
233	*p++ = ns[-1].c_c;
234	n = 5;
235	q = p;
236	while (j < wwncol && ns->c_m == m) {
237	*p++ = ns->c_c;
238	if (ns->c_w == os->c_w) {
239	if (--n <= 0)
240	break;
241	os++;
242	ns++;
243	} else {
244	n = 5;
245	q = p;
246	lastc = *os;
247	os++ = ns++;
248	}
249	j++;
250	}
251	n = q - buf;
252	if (!wwwrap \|\| i != wwnrow - 1 \|\| c + n != wwncol)
253	xxwrite(i, c, buf, n, m);
254	else if (tt.tt_inschar \|\| tt.tt_insspace) {
255	if (n > 1) {
256	q[-2] = q[-1];
257	n--;
258	} else
259	c--;
260	xxwrite(i, c, buf, n, m);
261	c += n - 1;
262	if (tt.tt_inschar)
263	xxinschar(i, c, ns[-2].c_c,
264	ns[-2].c_m);
265	else {
266	xxinsspace(i, c);
267	xxwrite(i, c, &ns[-2].c_c, 1,
268	ns[-2].c_m);
269	}
270	} else {
271	if (--n)
272	xxwrite(i, c, buf, n, m);
273	os[-1] = lastc;
274	*touched = WWU_TOUCHED;
275	}
276	didit = 1;
277	}
278	if (!didit)
279	wwnupdmiss++;
280	}
281	}