xref: /titanic_51/usr/src/cmd/mandoc/term.c (revision 25c28e83beb90e7c80452a7c818c5e6f73a07dc8)
1 /*	$Id: term.c,v 1.214 2013/12/25 00:39:31 schwarze Exp $ */
2 /*
3  * Copyright (c) 2008, 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
4  * Copyright (c) 2010, 2011, 2012, 2013 Ingo Schwarze <schwarze@openbsd.org>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 #ifdef HAVE_CONFIG_H
19 #include "config.h"
20 #endif
21 
22 #include <sys/types.h>
23 
24 #include <assert.h>
25 #include <ctype.h>
26 #include <stdint.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 
31 #include "mandoc.h"
32 #include "out.h"
33 #include "term.h"
34 #include "main.h"
35 
36 static	size_t		 cond_width(const struct termp *, int, int *);
37 static	void		 adjbuf(struct termp *p, size_t);
38 static	void		 bufferc(struct termp *, char);
39 static	void		 encode(struct termp *, const char *, size_t);
40 static	void		 encode1(struct termp *, int);
41 
42 void
43 term_free(struct termp *p)
44 {
45 
46 	if (p->buf)
47 		free(p->buf);
48 	if (p->symtab)
49 		mchars_free(p->symtab);
50 
51 	free(p);
52 }
53 
54 
55 void
56 term_begin(struct termp *p, term_margin head,
57 		term_margin foot, const void *arg)
58 {
59 
60 	p->headf = head;
61 	p->footf = foot;
62 	p->argf = arg;
63 	(*p->begin)(p);
64 }
65 
66 
67 void
68 term_end(struct termp *p)
69 {
70 
71 	(*p->end)(p);
72 }
73 
74 /*
75  * Flush a line of text.  A "line" is loosely defined as being something
76  * that should be followed by a newline, regardless of whether it's
77  * broken apart by newlines getting there.  A line can also be a
78  * fragment of a columnar list (`Bl -tag' or `Bl -column'), which does
79  * not have a trailing newline.
80  *
81  * The following flags may be specified:
82  *
83  *  - TERMP_NOBREAK: this is the most important and is used when making
84  *    columns.  In short: don't print a newline and instead expect the
85  *    next call to do the padding up to the start of the next column.
86  *    p->trailspace may be set to 0, 1, or 2, depending on how many
87  *    space characters are required at the end of the column.
88  *
89  *  - TERMP_DANGLE: don't newline when TERMP_NOBREAK is specified and
90  *    the line is overrun, and don't pad-right if it's underrun.
91  *
92  *  - TERMP_HANG: like TERMP_DANGLE, but doesn't newline when
93  *    overrunning, instead save the position and continue at that point
94  *    when the next invocation.
95  *
96  *  In-line line breaking:
97  *
98  *  If TERMP_NOBREAK is specified and the line overruns the right
99  *  margin, it will break and pad-right to the right margin after
100  *  writing.  If maxrmargin is violated, it will break and continue
101  *  writing from the right-margin, which will lead to the above scenario
102  *  upon exit.  Otherwise, the line will break at the right margin.
103  */
104 void
105 term_flushln(struct termp *p)
106 {
107 	size_t		 i;     /* current input position in p->buf */
108 	int		 ntab;	/* number of tabs to prepend */
109 	size_t		 vis;   /* current visual position on output */
110 	size_t		 vbl;   /* number of blanks to prepend to output */
111 	size_t		 vend;	/* end of word visual position on output */
112 	size_t		 bp;    /* visual right border position */
113 	size_t		 dv;    /* temporary for visual pos calculations */
114 	size_t		 j;     /* temporary loop index for p->buf */
115 	size_t		 jhy;	/* last hyph before overflow w/r/t j */
116 	size_t		 maxvis; /* output position of visible boundary */
117 	size_t		 mmax; /* used in calculating bp */
118 
119 	/*
120 	 * First, establish the maximum columns of "visible" content.
121 	 * This is usually the difference between the right-margin and
122 	 * an indentation, but can be, for tagged lists or columns, a
123 	 * small set of values.
124 	 *
125 	 * The following unsigned-signed subtractions look strange,
126 	 * but they are actually correct.  If the int p->overstep
127 	 * is negative, it gets sign extended.  Subtracting that
128 	 * very large size_t effectively adds a small number to dv.
129 	 */
130 	assert  (p->rmargin >= p->offset);
131 	dv     = p->rmargin - p->offset;
132 	maxvis = (int)dv > p->overstep ? dv - (size_t)p->overstep : 0;
133 	dv     = p->maxrmargin - p->offset;
134 	mmax   = (int)dv > p->overstep ? dv - (size_t)p->overstep : 0;
135 
136 	bp = TERMP_NOBREAK & p->flags ? mmax : maxvis;
137 
138 	/*
139 	 * Calculate the required amount of padding.
140 	 */
141 	vbl = p->offset + p->overstep > p->viscol ?
142 	      p->offset + p->overstep - p->viscol : 0;
143 
144 	vis = vend = 0;
145 	i = 0;
146 
147 	while (i < p->col) {
148 		/*
149 		 * Handle literal tab characters: collapse all
150 		 * subsequent tabs into a single huge set of spaces.
151 		 */
152 		ntab = 0;
153 		while (i < p->col && '\t' == p->buf[i]) {
154 			vend = (vis / p->tabwidth + 1) * p->tabwidth;
155 			vbl += vend - vis;
156 			vis = vend;
157 			ntab++;
158 			i++;
159 		}
160 
161 		/*
162 		 * Count up visible word characters.  Control sequences
163 		 * (starting with the CSI) aren't counted.  A space
164 		 * generates a non-printing word, which is valid (the
165 		 * space is printed according to regular spacing rules).
166 		 */
167 
168 		for (j = i, jhy = 0; j < p->col; j++) {
169 			if (' ' == p->buf[j] || '\t' == p->buf[j])
170 				break;
171 
172 			/* Back over the the last printed character. */
173 			if (8 == p->buf[j]) {
174 				assert(j);
175 				vend -= (*p->width)(p, p->buf[j - 1]);
176 				continue;
177 			}
178 
179 			/* Regular word. */
180 			/* Break at the hyphen point if we overrun. */
181 			if (vend > vis && vend < bp &&
182 					ASCII_HYPH == p->buf[j])
183 				jhy = j;
184 
185 			vend += (*p->width)(p, p->buf[j]);
186 		}
187 
188 		/*
189 		 * Find out whether we would exceed the right margin.
190 		 * If so, break to the next line.
191 		 */
192 		if (vend > bp && 0 == jhy && vis > 0) {
193 			vend -= vis;
194 			(*p->endline)(p);
195 			p->viscol = 0;
196 			if (TERMP_NOBREAK & p->flags) {
197 				vbl = p->rmargin;
198 				vend += p->rmargin - p->offset;
199 			} else
200 				vbl = p->offset;
201 
202 			/* use pending tabs on the new line */
203 
204 			if (0 < ntab)
205 				vbl += ntab * p->tabwidth;
206 
207 			/*
208 			 * Remove the p->overstep width.
209 			 * Again, if p->overstep is negative,
210 			 * sign extension does the right thing.
211 			 */
212 
213 			bp += (size_t)p->overstep;
214 			p->overstep = 0;
215 		}
216 
217 		/* Write out the [remaining] word. */
218 		for ( ; i < p->col; i++) {
219 			if (vend > bp && jhy > 0 && i > jhy)
220 				break;
221 			if ('\t' == p->buf[i])
222 				break;
223 			if (' ' == p->buf[i]) {
224 				j = i;
225 				while (' ' == p->buf[i])
226 					i++;
227 				dv = (i - j) * (*p->width)(p, ' ');
228 				vbl += dv;
229 				vend += dv;
230 				break;
231 			}
232 			if (ASCII_NBRSP == p->buf[i]) {
233 				vbl += (*p->width)(p, ' ');
234 				continue;
235 			}
236 
237 			/*
238 			 * Now we definitely know there will be
239 			 * printable characters to output,
240 			 * so write preceding white space now.
241 			 */
242 			if (vbl) {
243 				(*p->advance)(p, vbl);
244 				p->viscol += vbl;
245 				vbl = 0;
246 			}
247 
248 			if (ASCII_HYPH == p->buf[i]) {
249 				(*p->letter)(p, '-');
250 				p->viscol += (*p->width)(p, '-');
251 				continue;
252 			}
253 
254 			(*p->letter)(p, p->buf[i]);
255 			if (8 == p->buf[i])
256 				p->viscol -= (*p->width)(p, p->buf[i-1]);
257 			else
258 				p->viscol += (*p->width)(p, p->buf[i]);
259 		}
260 		vis = vend;
261 	}
262 
263 	/*
264 	 * If there was trailing white space, it was not printed;
265 	 * so reset the cursor position accordingly.
266 	 */
267 	if (vis)
268 		vis -= vbl;
269 
270 	p->col = 0;
271 	p->overstep = 0;
272 
273 	if ( ! (TERMP_NOBREAK & p->flags)) {
274 		p->viscol = 0;
275 		(*p->endline)(p);
276 		return;
277 	}
278 
279 	if (TERMP_HANG & p->flags) {
280 		p->overstep = (int)(vis - maxvis +
281 				p->trailspace * (*p->width)(p, ' '));
282 
283 		/*
284 		 * If we have overstepped the margin, temporarily move
285 		 * it to the right and flag the rest of the line to be
286 		 * shorter.
287 		 * If there is a request to keep the columns together,
288 		 * allow negative overstep when the column is not full.
289 		 */
290 		if (p->trailspace && p->overstep < 0)
291 			p->overstep = 0;
292 		return;
293 
294 	} else if (TERMP_DANGLE & p->flags)
295 		return;
296 
297 	/* If the column was overrun, break the line. */
298 	if (maxvis < vis + p->trailspace * (*p->width)(p, ' ')) {
299 		(*p->endline)(p);
300 		p->viscol = 0;
301 	}
302 }
303 
304 
305 /*
306  * A newline only breaks an existing line; it won't assert vertical
307  * space.  All data in the output buffer is flushed prior to the newline
308  * assertion.
309  */
310 void
311 term_newln(struct termp *p)
312 {
313 
314 	p->flags |= TERMP_NOSPACE;
315 	if (p->col || p->viscol)
316 		term_flushln(p);
317 }
318 
319 
320 /*
321  * Asserts a vertical space (a full, empty line-break between lines).
322  * Note that if used twice, this will cause two blank spaces and so on.
323  * All data in the output buffer is flushed prior to the newline
324  * assertion.
325  */
326 void
327 term_vspace(struct termp *p)
328 {
329 
330 	term_newln(p);
331 	p->viscol = 0;
332 	if (0 < p->skipvsp)
333 		p->skipvsp--;
334 	else
335 		(*p->endline)(p);
336 }
337 
338 void
339 term_fontlast(struct termp *p)
340 {
341 	enum termfont	 f;
342 
343 	f = p->fontl;
344 	p->fontl = p->fontq[p->fonti];
345 	p->fontq[p->fonti] = f;
346 }
347 
348 
349 void
350 term_fontrepl(struct termp *p, enum termfont f)
351 {
352 
353 	p->fontl = p->fontq[p->fonti];
354 	p->fontq[p->fonti] = f;
355 }
356 
357 
358 void
359 term_fontpush(struct termp *p, enum termfont f)
360 {
361 
362 	assert(p->fonti + 1 < 10);
363 	p->fontl = p->fontq[p->fonti];
364 	p->fontq[++p->fonti] = f;
365 }
366 
367 
368 const void *
369 term_fontq(struct termp *p)
370 {
371 
372 	return(&p->fontq[p->fonti]);
373 }
374 
375 
376 enum termfont
377 term_fonttop(struct termp *p)
378 {
379 
380 	return(p->fontq[p->fonti]);
381 }
382 
383 
384 void
385 term_fontpopq(struct termp *p, const void *key)
386 {
387 
388 	while (p->fonti >= 0 && key < (void *)(p->fontq + p->fonti))
389 		p->fonti--;
390 	assert(p->fonti >= 0);
391 }
392 
393 
394 void
395 term_fontpop(struct termp *p)
396 {
397 
398 	assert(p->fonti);
399 	p->fonti--;
400 }
401 
402 /*
403  * Handle pwords, partial words, which may be either a single word or a
404  * phrase that cannot be broken down (such as a literal string).  This
405  * handles word styling.
406  */
407 void
408 term_word(struct termp *p, const char *word)
409 {
410 	const char	 nbrsp[2] = { ASCII_NBRSP, 0 };
411 	const char	*seq, *cp;
412 	char		 c;
413 	int		 sz, uc;
414 	size_t		 ssz;
415 	enum mandoc_esc	 esc;
416 
417 	if ( ! (TERMP_NOSPACE & p->flags)) {
418 		if ( ! (TERMP_KEEP & p->flags)) {
419 			bufferc(p, ' ');
420 			if (TERMP_SENTENCE & p->flags)
421 				bufferc(p, ' ');
422 		} else
423 			bufferc(p, ASCII_NBRSP);
424 	}
425 	if (TERMP_PREKEEP & p->flags)
426 		p->flags |= TERMP_KEEP;
427 
428 	if ( ! (p->flags & TERMP_NONOSPACE))
429 		p->flags &= ~TERMP_NOSPACE;
430 	else
431 		p->flags |= TERMP_NOSPACE;
432 
433 	p->flags &= ~TERMP_SENTENCE;
434 
435 	while ('\0' != *word) {
436 		if ('\\' != *word) {
437 			if (TERMP_SKIPCHAR & p->flags) {
438 				p->flags &= ~TERMP_SKIPCHAR;
439 				word++;
440 				continue;
441 			}
442 			if (TERMP_NBRWORD & p->flags) {
443 				if (' ' == *word) {
444 					encode(p, nbrsp, 1);
445 					word++;
446 					continue;
447 				}
448 				ssz = strcspn(word, "\\ ");
449 			} else
450 				ssz = strcspn(word, "\\");
451 			encode(p, word, ssz);
452 			word += (int)ssz;
453 			continue;
454 		}
455 
456 		word++;
457 		esc = mandoc_escape(&word, &seq, &sz);
458 		if (ESCAPE_ERROR == esc)
459 			break;
460 
461 		if (TERMENC_ASCII != p->enc)
462 			switch (esc) {
463 			case (ESCAPE_UNICODE):
464 				uc = mchars_num2uc(seq + 1, sz - 1);
465 				if ('\0' == uc)
466 					break;
467 				encode1(p, uc);
468 				continue;
469 			case (ESCAPE_SPECIAL):
470 				uc = mchars_spec2cp(p->symtab, seq, sz);
471 				if (uc <= 0)
472 					break;
473 				encode1(p, uc);
474 				continue;
475 			default:
476 				break;
477 			}
478 
479 		switch (esc) {
480 		case (ESCAPE_UNICODE):
481 			encode1(p, '?');
482 			break;
483 		case (ESCAPE_NUMBERED):
484 			c = mchars_num2char(seq, sz);
485 			if ('\0' != c)
486 				encode(p, &c, 1);
487 			break;
488 		case (ESCAPE_SPECIAL):
489 			cp = mchars_spec2str(p->symtab, seq, sz, &ssz);
490 			if (NULL != cp)
491 				encode(p, cp, ssz);
492 			else if (1 == ssz)
493 				encode(p, seq, sz);
494 			break;
495 		case (ESCAPE_FONTBOLD):
496 			term_fontrepl(p, TERMFONT_BOLD);
497 			break;
498 		case (ESCAPE_FONTITALIC):
499 			term_fontrepl(p, TERMFONT_UNDER);
500 			break;
501 		case (ESCAPE_FONTBI):
502 			term_fontrepl(p, TERMFONT_BI);
503 			break;
504 		case (ESCAPE_FONT):
505 			/* FALLTHROUGH */
506 		case (ESCAPE_FONTROMAN):
507 			term_fontrepl(p, TERMFONT_NONE);
508 			break;
509 		case (ESCAPE_FONTPREV):
510 			term_fontlast(p);
511 			break;
512 		case (ESCAPE_NOSPACE):
513 			if (TERMP_SKIPCHAR & p->flags)
514 				p->flags &= ~TERMP_SKIPCHAR;
515 			else if ('\0' == *word)
516 				p->flags |= TERMP_NOSPACE;
517 			break;
518 		case (ESCAPE_SKIPCHAR):
519 			p->flags |= TERMP_SKIPCHAR;
520 			break;
521 		default:
522 			break;
523 		}
524 	}
525 	p->flags &= ~TERMP_NBRWORD;
526 }
527 
528 static void
529 adjbuf(struct termp *p, size_t sz)
530 {
531 
532 	if (0 == p->maxcols)
533 		p->maxcols = 1024;
534 	while (sz >= p->maxcols)
535 		p->maxcols <<= 2;
536 
537 	p->buf = mandoc_realloc(p->buf, sizeof(int) * p->maxcols);
538 }
539 
540 static void
541 bufferc(struct termp *p, char c)
542 {
543 
544 	if (p->col + 1 >= p->maxcols)
545 		adjbuf(p, p->col + 1);
546 
547 	p->buf[p->col++] = c;
548 }
549 
550 /*
551  * See encode().
552  * Do this for a single (probably unicode) value.
553  * Does not check for non-decorated glyphs.
554  */
555 static void
556 encode1(struct termp *p, int c)
557 {
558 	enum termfont	  f;
559 
560 	if (TERMP_SKIPCHAR & p->flags) {
561 		p->flags &= ~TERMP_SKIPCHAR;
562 		return;
563 	}
564 
565 	if (p->col + 6 >= p->maxcols)
566 		adjbuf(p, p->col + 6);
567 
568 	f = term_fonttop(p);
569 
570 	if (TERMFONT_UNDER == f || TERMFONT_BI == f) {
571 		p->buf[p->col++] = '_';
572 		p->buf[p->col++] = 8;
573 	}
574 	if (TERMFONT_BOLD == f || TERMFONT_BI == f) {
575 		if (ASCII_HYPH == c)
576 			p->buf[p->col++] = '-';
577 		else
578 			p->buf[p->col++] = c;
579 		p->buf[p->col++] = 8;
580 	}
581 	p->buf[p->col++] = c;
582 }
583 
584 static void
585 encode(struct termp *p, const char *word, size_t sz)
586 {
587 	size_t		  i;
588 
589 	if (TERMP_SKIPCHAR & p->flags) {
590 		p->flags &= ~TERMP_SKIPCHAR;
591 		return;
592 	}
593 
594 	/*
595 	 * Encode and buffer a string of characters.  If the current
596 	 * font mode is unset, buffer directly, else encode then buffer
597 	 * character by character.
598 	 */
599 
600 	if (TERMFONT_NONE == term_fonttop(p)) {
601 		if (p->col + sz >= p->maxcols)
602 			adjbuf(p, p->col + sz);
603 		for (i = 0; i < sz; i++)
604 			p->buf[p->col++] = word[i];
605 		return;
606 	}
607 
608 	/* Pre-buffer, assuming worst-case. */
609 
610 	if (p->col + 1 + (sz * 5) >= p->maxcols)
611 		adjbuf(p, p->col + 1 + (sz * 5));
612 
613 	for (i = 0; i < sz; i++) {
614 		if (ASCII_HYPH == word[i] ||
615 		    isgraph((unsigned char)word[i]))
616 			encode1(p, word[i]);
617 		else
618 			p->buf[p->col++] = word[i];
619 	}
620 }
621 
622 size_t
623 term_len(const struct termp *p, size_t sz)
624 {
625 
626 	return((*p->width)(p, ' ') * sz);
627 }
628 
629 static size_t
630 cond_width(const struct termp *p, int c, int *skip)
631 {
632 
633 	if (*skip) {
634 		(*skip) = 0;
635 		return(0);
636 	} else
637 		return((*p->width)(p, c));
638 }
639 
640 size_t
641 term_strlen(const struct termp *p, const char *cp)
642 {
643 	size_t		 sz, rsz, i;
644 	int		 ssz, skip, c;
645 	const char	*seq, *rhs;
646 	enum mandoc_esc	 esc;
647 	static const char rej[] = { '\\', ASCII_HYPH, ASCII_NBRSP, '\0' };
648 
649 	/*
650 	 * Account for escaped sequences within string length
651 	 * calculations.  This follows the logic in term_word() as we
652 	 * must calculate the width of produced strings.
653 	 */
654 
655 	sz = 0;
656 	skip = 0;
657 	while ('\0' != *cp) {
658 		rsz = strcspn(cp, rej);
659 		for (i = 0; i < rsz; i++)
660 			sz += cond_width(p, *cp++, &skip);
661 
662 		c = 0;
663 		switch (*cp) {
664 		case ('\\'):
665 			cp++;
666 			esc = mandoc_escape(&cp, &seq, &ssz);
667 			if (ESCAPE_ERROR == esc)
668 				return(sz);
669 
670 			if (TERMENC_ASCII != p->enc)
671 				switch (esc) {
672 				case (ESCAPE_UNICODE):
673 					c = mchars_num2uc
674 						(seq + 1, ssz - 1);
675 					if ('\0' == c)
676 						break;
677 					sz += cond_width(p, c, &skip);
678 					continue;
679 				case (ESCAPE_SPECIAL):
680 					c = mchars_spec2cp
681 						(p->symtab, seq, ssz);
682 					if (c <= 0)
683 						break;
684 					sz += cond_width(p, c, &skip);
685 					continue;
686 				default:
687 					break;
688 				}
689 
690 			rhs = NULL;
691 
692 			switch (esc) {
693 			case (ESCAPE_UNICODE):
694 				sz += cond_width(p, '?', &skip);
695 				break;
696 			case (ESCAPE_NUMBERED):
697 				c = mchars_num2char(seq, ssz);
698 				if ('\0' != c)
699 					sz += cond_width(p, c, &skip);
700 				break;
701 			case (ESCAPE_SPECIAL):
702 				rhs = mchars_spec2str
703 					(p->symtab, seq, ssz, &rsz);
704 
705 				if (ssz != 1 || rhs)
706 					break;
707 
708 				rhs = seq;
709 				rsz = ssz;
710 				break;
711 			case (ESCAPE_SKIPCHAR):
712 				skip = 1;
713 				break;
714 			default:
715 				break;
716 			}
717 
718 			if (NULL == rhs)
719 				break;
720 
721 			if (skip) {
722 				skip = 0;
723 				break;
724 			}
725 
726 			for (i = 0; i < rsz; i++)
727 				sz += (*p->width)(p, *rhs++);
728 			break;
729 		case (ASCII_NBRSP):
730 			sz += cond_width(p, ' ', &skip);
731 			cp++;
732 			break;
733 		case (ASCII_HYPH):
734 			sz += cond_width(p, '-', &skip);
735 			cp++;
736 			break;
737 		default:
738 			break;
739 		}
740 	}
741 
742 	return(sz);
743 }
744 
745 /* ARGSUSED */
746 size_t
747 term_vspan(const struct termp *p, const struct roffsu *su)
748 {
749 	double		 r;
750 
751 	switch (su->unit) {
752 	case (SCALE_CM):
753 		r = su->scale * 2;
754 		break;
755 	case (SCALE_IN):
756 		r = su->scale * 6;
757 		break;
758 	case (SCALE_PC):
759 		r = su->scale;
760 		break;
761 	case (SCALE_PT):
762 		r = su->scale / 8;
763 		break;
764 	case (SCALE_MM):
765 		r = su->scale / 1000;
766 		break;
767 	case (SCALE_VS):
768 		r = su->scale;
769 		break;
770 	default:
771 		r = su->scale - 1;
772 		break;
773 	}
774 
775 	if (r < 0.0)
776 		r = 0.0;
777 	return(/* LINTED */(size_t)
778 			r);
779 }
780 
781 size_t
782 term_hspan(const struct termp *p, const struct roffsu *su)
783 {
784 	double		 v;
785 
786 	v = ((*p->hspan)(p, su));
787 	if (v < 0.0)
788 		v = 0.0;
789 	return((size_t) /* LINTED */
790 			v);
791 }
792