xref: /netbsd-src/lib/libcurses/cr_put.c (revision d9158b13b5dfe46201430699a3f7a235ecf28df3)
1 /*
2  * Copyright (c) 1981, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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 #ifndef lint
35 /* from: static char sccsid[] = "@(#)cr_put.c	8.2 (Berkeley) 1/9/94"; */
36 static char *rcsid = "$Id: cr_put.c,v 1.7 1994/01/24 08:36:42 cgd Exp $";
37 #endif	/* not lint */
38 
39 #include <curses.h>
40 #include <string.h>
41 
42 #define	HARDTABS	8
43 
44 /*
45  * Terminal driving and line formatting routines.  Basic motion optimizations
46  * are done here as well as formatting lines (printing of control characters,
47  * line numbering and the like).
48  */
49 
50 /* Stub function for the users. */
51 int
52 mvcur(ly, lx, y, x)
53 	int ly, lx, y, x;
54 {
55 	return (__mvcur(ly, lx, y, x, 0));
56 }
57 
58 static void	fgoto __P((int));
59 static int	plod __P((int, int));
60 static void	plodput __P((int));
61 static int	tabcol __P((int, int));
62 
63 static int outcol, outline, destcol, destline;
64 
65 /*
66  * Sync the position of the output cursor.  Most work here is rounding for
67  * terminal boundaries getting the column position implied by wraparound or
68  * the lack thereof and rolling up the screen to get destline on the screen.
69  */
70 int
71 __mvcur(ly, lx, y, x, in_refresh)
72 	int ly, lx, y, x, in_refresh;
73 {
74 #ifdef DEBUG
75 	__CTRACE("mvcur: moving cursor from (%d, %d) to (%d, %d)\n",
76 	    ly, lx, y, x);
77 #endif
78 	destcol = x;
79 	destline = y;
80 	outcol = lx;
81 	outline = ly;
82 	fgoto(in_refresh);
83 	return (OK);
84 }
85 
86 static void
87 fgoto(in_refresh)
88 	int in_refresh;
89 {
90 	register int c, l;
91 	register char *cgp;
92 
93 	if (destcol >= COLS) {
94 		destline += destcol / COLS;
95 		destcol %= COLS;
96 	}
97 	if (outcol >= COLS) {
98 		l = (outcol + 1) / COLS;
99 		outline += l;
100 		outcol %= COLS;
101 		if (AM == 0) {
102 			while (l > 0) {
103 				if (__pfast)
104 					if (CR)
105 						tputs(CR, 0, __cputchar);
106 					else
107 						putchar('\r');
108 				if (NL)
109 					tputs(NL, 0, __cputchar);
110 				else
111 					putchar('\n');
112 				l--;
113 			}
114 			outcol = 0;
115 		}
116 		if (outline > LINES - 1) {
117 			destline -= outline - (LINES - 1);
118 			outline = LINES - 1;
119 		}
120 	}
121 	if (destline >= LINES) {
122 		l = destline;
123 		destline = LINES - 1;
124 		if (outline < LINES - 1) {
125 			c = destcol;
126 			if (__pfast == 0 && !CA)
127 				destcol = 0;
128 			fgoto(in_refresh);
129 			destcol = c;
130 		}
131 		while (l >= LINES) {
132 			/* The following linefeed (or simulation thereof) is
133 			 * supposed to scroll up the screen, since we are on
134 			 * the bottom line.  We make the assumption that
135 			 * linefeed will scroll.  If ns is in the capability
136 			 * list this won't work.  We should probably have an
137 			 * sc capability but sf will generally take the place
138 			 * if it works.
139 			 *
140 			 * Superbee glitch: in the middle of the screen have
141 			 * to use esc B (down) because linefeed screws up in
142 			 * "Efficient Paging" (what a joke) mode (which is
143 			 * essential in some SB's because CRLF mode puts
144 			 * garbage in at end of memory), but you must use
145 			 * linefeed to scroll since down arrow won't go past
146 			 * memory end. I turned this off after recieving Paul
147 			 * Eggert's Superbee description which wins better.
148 			 */
149 			if (NL /* && !XB */ && __pfast)
150 				tputs(NL, 0, __cputchar);
151 			else
152 				putchar('\n');
153 			l--;
154 			if (__pfast == 0)
155 				outcol = 0;
156 		}
157 	}
158 	if (destline < outline && !(CA || UP))
159 		destline = outline;
160 	if (CA) {
161 		cgp = tgoto(CM, destcol, destline);
162 
163 		/*
164 		 * Need this condition due to inconsistent behavior
165 		 * of backspace on the last column.
166 		 */
167 		if (outcol != COLS - 1 && plod(strlen(cgp), in_refresh) > 0)
168 			plod(0, in_refresh);
169 		else
170 			tputs(cgp, 0, __cputchar);
171 	} else
172 		plod(0, in_refresh);
173 	outline = destline;
174 	outcol = destcol;
175 }
176 /*
177  * Move (slowly) to destination.
178  * Hard thing here is using home cursor on really deficient terminals.
179  * Otherwise just use cursor motions, hacking use of tabs and overtabbing
180  * and backspace.
181  */
182 
183 static int plodcnt, plodflg;
184 
185 static void
186 plodput(c)
187 	int c;
188 {
189 	if (plodflg)
190 		--plodcnt;
191 	else
192 		putchar(c);
193 }
194 
195 static int
196 plod(cnt, in_refresh)
197 	int cnt, in_refresh;
198 {
199 	register int i, j, k, soutcol, soutline;
200 
201 	plodcnt = plodflg = cnt;
202 	soutcol = outcol;
203 	soutline = outline;
204 	/*
205 	 * Consider homing and moving down/right from there, vs. moving
206 	 * directly with local motions to the right spot.
207 	 */
208 	if (HO) {
209 		/*
210 		 * i is the cost to home and tab/space to the right to get to
211 		 * the proper column.  This assumes ND space costs 1 char.  So
212 		 * i + destcol is cost of motion with home.
213 		 */
214 		if (GT)
215 			i = (destcol / HARDTABS) + (destcol % HARDTABS);
216 		else
217 			i = destcol;
218 
219 		/* j is cost to move locally without homing. */
220 		if (destcol >= outcol) {	/* if motion is to the right */
221 			j = destcol / HARDTABS - outcol / HARDTABS;
222 			if (GT && j)
223 				j += destcol % HARDTABS;
224 			else
225 				j = destcol - outcol;
226 		} else
227 			/* leftward motion only works if we can backspace. */
228 			if (outcol - destcol <= i && (BS || BC))
229 				/* Cheaper to backspace. */
230 				i = j = outcol - destcol;
231 			else
232 				/* Impossibly expensive. */
233 				j = i + 1;
234 
235 		/* k is the absolute value of vertical distance. */
236 		k = outline - destline;
237 		if (k < 0)
238 			k = -k;
239 		j += k;
240 
241 		/* Decision.  We may not have a choice if no UP. */
242 		if (i + destline < j || (!UP && destline < outline)) {
243 			/*
244 			 * Cheaper to home.  Do it now and pretend it's a
245 			 * regular local motion.
246 			 */
247 			tputs(HO, 0, plodput);
248 			outcol = outline = 0;
249 		} else if (LL) {
250 			/*
251 			 * Quickly consider homing down and moving from there.
252 			 * Assume cost of LL is 2.
253 			 */
254 			k = (LINES - 1) - destline;
255 			if (i + k + 2 < j && (k <= 0 || UP)) {
256 				tputs(LL, 0, plodput);
257 				outcol = 0;
258 				outline = LINES - 1;
259 			}
260 		}
261 	} else
262 		/* No home and no up means it's impossible. */
263 		if (!UP && destline < outline)
264 			return (-1);
265 	if (GT)
266 		i = destcol % HARDTABS + destcol / HARDTABS;
267 	else
268 		i = destcol;
269 #ifdef notdef
270 	if (BT && outcol > destcol &&
271 	    (j = (((outcol+7) & ~7) - destcol - 1) >> 3)) {
272 		j *= (k = strlen(BT));
273 		if ((k += (destcol&7)) > 4)
274 			j += 8 - (destcol&7);
275 		else
276 			j += k;
277 	}
278 	else
279 #endif
280 		j = outcol - destcol;
281 
282 	/*
283 	 * If we will later need a \n which will turn into a \r\n by the
284 	 * system or the terminal, then don't bother to try to \r.
285 	 */
286 	if ((NONL || !__pfast) && outline < destline)
287 		goto dontcr;
288 
289 	/*
290 	 * If the terminal will do a \r\n and there isn't room for it, then
291 	 * we can't afford a \r.
292 	 */
293 	if (NC && outline >= destline)
294 		goto dontcr;
295 
296 	/*
297 	 * If it will be cheaper, or if we can't back up, then send a return
298 	 * preliminarily.
299 	 */
300 	if (j > i + 1 || outcol > destcol && !BS && !BC) {
301 		/*
302 		 * BUG: this doesn't take the (possibly long) length of CR
303 		 * into account.
304 		 */
305 		if (CR)
306 			tputs(CR, 0, plodput);
307 		else
308 			plodput('\r');
309 		if (NC) {
310 			if (NL)
311 				tputs(NL, 0, plodput);
312 			else
313 				plodput('\n');
314 			outline++;
315 		}
316 		outcol = 0;
317 	}
318 
319 dontcr:	while (outline < destline) {
320 		outline++;
321 		if (NL)
322 			tputs(NL, 0, plodput);
323 		else
324 			plodput('\n');
325 		if (plodcnt < 0)
326 			goto out;
327 		if (NONL || __pfast == 0)
328 			outcol = 0;
329 	}
330 	if (BT)
331 		k = strlen(BT);
332 	while (outcol > destcol) {
333 		if (plodcnt < 0)
334 			goto out;
335 #ifdef notdef
336 		if (BT && outcol - destcol > k + 4) {
337 			tputs(BT, 0, plodput);
338 			outcol--;
339 			outcol &= ~7;
340 			continue;
341 		}
342 #endif
343 		outcol--;
344 		if (BC)
345 			tputs(BC, 0, plodput);
346 		else
347 			plodput('\b');
348 	}
349 	while (outline > destline) {
350 		outline--;
351 		tputs(UP, 0, plodput);
352 		if (plodcnt < 0)
353 			goto out;
354 	}
355 	if (GT && destcol - outcol > 1) {
356 		for (;;) {
357 			i = tabcol(outcol, HARDTABS);
358 			if (i > destcol)
359 				break;
360 			if (TA)
361 				tputs(TA, 0, plodput);
362 			else
363 				plodput('\t');
364 			outcol = i;
365 		}
366 		if (destcol - outcol > 4 && i < COLS && (BC || BS)) {
367 			if (TA)
368 				tputs(TA, 0, plodput);
369 			else
370 				plodput('\t');
371 			outcol = i;
372 			while (outcol > destcol) {
373 				outcol--;
374 				if (BC)
375 					tputs(BC, 0, plodput);
376 				else
377 					plodput('\b');
378 			}
379 		}
380 	}
381 	while (outcol < destcol) {
382 		/*
383 		 * Move one char to the right.  We don't use ND space because
384 		 * it's better to just print the char we are moving over.
385 		 */
386 		if (in_refresh)
387 			if (plodflg)	/* Avoid a complex calculation. */
388 				plodcnt--;
389 			else {
390 				i = curscr->lines[outline]->line[outcol].ch;
391 				if ((curscr->lines[outline]->line[outcol].attr
392 				     & __STANDOUT) ==
393 				    (curscr->flags & __WSTANDOUT))
394 					putchar(i);
395 				else
396 					goto nondes;
397 			}
398 		else
399 nondes:			if (ND)
400 				tputs(ND, 0, plodput);
401 			else
402 				plodput(' ');
403 		outcol++;
404 		if (plodcnt < 0)
405 			goto out;
406 	}
407 
408 out:	if (plodflg) {
409 		outcol = soutcol;
410 		outline = soutline;
411 	}
412 	return (plodcnt);
413 }
414 
415 /*
416  * Return the column number that results from being in column col and
417  * hitting a tab, where tabs are set every ts columns.  Work right for
418  * the case where col > COLS, even if ts does not divide COLS.
419  */
420 static int
421 tabcol(col, ts)
422 	int col, ts;
423 {
424 	int offset;
425 
426 	if (col >= COLS) {
427 		offset = COLS * (col / COLS);
428 		col -= offset;
429 	} else
430 		offset = 0;
431 	return (col + ts - (col % ts) + offset);
432 }
433