1/*	$Id: term.c,v 1.274 2017/07/28 14:25:48 schwarze Exp $ */
2/*
3 * Copyright (c) 2008, 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
4 * Copyright (c) 2010-2017 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 AUTHORS DISCLAIM ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHORS 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#include "config.h"
19
20#include <sys/types.h>
21
22#include <assert.h>
23#include <ctype.h>
24#include <stdio.h>
25#include <stdlib.h>
26#include <string.h>
27
28#include "mandoc.h"
29#include "mandoc_aux.h"
30#include "out.h"
31#include "term.h"
32#include "main.h"
33
34static	size_t		 cond_width(const struct termp *, int, int *);
35static	void		 adjbuf(struct termp_col *, size_t);
36static	void		 bufferc(struct termp *, char);
37static	void		 encode(struct termp *, const char *, size_t);
38static	void		 encode1(struct termp *, int);
39static	void		 endline(struct termp *);
40
41
42void
43term_setcol(struct termp *p, size_t maxtcol)
44{
45	if (maxtcol > p->maxtcol) {
46		p->tcols = mandoc_recallocarray(p->tcols,
47		    p->maxtcol, maxtcol, sizeof(*p->tcols));
48		p->maxtcol = maxtcol;
49	}
50	p->lasttcol = maxtcol - 1;
51	p->tcol = p->tcols;
52}
53
54void
55term_free(struct termp *p)
56{
57	for (p->tcol = p->tcols; p->tcol < p->tcols + p->maxtcol; p->tcol++)
58		free(p->tcol->buf);
59	free(p->tcols);
60	free(p->fontq);
61	free(p);
62}
63
64void
65term_begin(struct termp *p, term_margin head,
66		term_margin foot, const struct roff_meta *arg)
67{
68
69	p->headf = head;
70	p->footf = foot;
71	p->argf = arg;
72	(*p->begin)(p);
73}
74
75void
76term_end(struct termp *p)
77{
78
79	(*p->end)(p);
80}
81
82/*
83 * Flush a chunk of text.  By default, break the output line each time
84 * the right margin is reached, and continue output on the next line
85 * at the same offset as the chunk itself.  By default, also break the
86 * output line at the end of the chunk.
87 * The following flags may be specified:
88 *
89 *  - TERMP_NOBREAK: Do not break the output line at the right margin,
90 *    but only at the max right margin.  Also, do not break the output
91 *    line at the end of the chunk, such that the next call can pad to
92 *    the next column.  However, if less than p->trailspace blanks,
93 *    which can be 0, 1, or 2, remain to the right margin, the line
94 *    will be broken.
95 *  - TERMP_BRTRSP: Consider trailing whitespace significant
96 *    when deciding whether the chunk fits or not.
97 *  - TERMP_BRIND: If the chunk does not fit and the output line has
98 *    to be broken, start the next line at the right margin instead
99 *    of at the offset.  Used together with TERMP_NOBREAK for the tags
100 *    in various kinds of tagged lists.
101 *  - TERMP_HANG: Do not break the output line at the right margin,
102 *    append the next chunk after it even if this one is too long.
103 *    To be used together with TERMP_NOBREAK.
104 *  - TERMP_NOPAD: Start writing at the current position,
105 *    do not pad with blank characters up to the offset.
106 */
107void
108term_flushln(struct termp *p)
109{
110	size_t		 vis;   /* current visual position on output */
111	size_t		 vbl;   /* number of blanks to prepend to output */
112	size_t		 vend;	/* end of word visual position on output */
113	size_t		 bp;    /* visual right border position */
114	size_t		 dv;    /* temporary for visual pos calculations */
115	size_t		 j;     /* temporary loop index for p->tcol->buf */
116	size_t		 jhy;	/* last hyph before overflow w/r/t j */
117	size_t		 maxvis; /* output position of visible boundary */
118	int		 ntab;	/* number of tabs to prepend */
119	int		 breakline; /* after this word */
120
121	vbl = (p->flags & TERMP_NOPAD) || p->tcol->offset < p->viscol ?
122	    0 : p->tcol->offset - p->viscol;
123	if (p->minbl && vbl < p->minbl)
124		vbl = p->minbl;
125	maxvis = p->tcol->rmargin > p->viscol + vbl ?
126	    p->tcol->rmargin - p->viscol - vbl : 0;
127	bp = !(p->flags & TERMP_NOBREAK) ? maxvis :
128	    p->maxrmargin > p->viscol + vbl ?
129	    p->maxrmargin - p->viscol - vbl : 0;
130	vis = vend = 0;
131
132	if ((p->flags & TERMP_MULTICOL) == 0)
133		p->tcol->col = 0;
134	while (p->tcol->col < p->tcol->lastcol) {
135
136		/*
137		 * Handle literal tab characters: collapse all
138		 * subsequent tabs into a single huge set of spaces.
139		 */
140
141		ntab = 0;
142		while (p->tcol->col < p->tcol->lastcol &&
143		    p->tcol->buf[p->tcol->col] == '\t') {
144			vend = term_tab_next(vis);
145			vbl += vend - vis;
146			vis = vend;
147			ntab++;
148			p->tcol->col++;
149		}
150
151		/*
152		 * Count up visible word characters.  Control sequences
153		 * (starting with the CSI) aren't counted.  A space
154		 * generates a non-printing word, which is valid (the
155		 * space is printed according to regular spacing rules).
156		 */
157
158		jhy = 0;
159		breakline = 0;
160		for (j = p->tcol->col; j < p->tcol->lastcol; j++) {
161			if (p->tcol->buf[j] == '\n') {
162				if ((p->flags & TERMP_BRIND) == 0)
163					breakline = 1;
164				continue;
165			}
166			if (p->tcol->buf[j] == ' ' || p->tcol->buf[j] == '\t')
167				break;
168
169			/* Back over the last printed character. */
170			if (p->tcol->buf[j] == '\b') {
171				assert(j);
172				vend -= (*p->width)(p, p->tcol->buf[j - 1]);
173				continue;
174			}
175
176			/* Regular word. */
177			/* Break at the hyphen point if we overrun. */
178			if (vend > vis && vend < bp &&
179			    (p->tcol->buf[j] == ASCII_HYPH||
180			     p->tcol->buf[j] == ASCII_BREAK))
181				jhy = j;
182
183			/*
184			 * Hyphenation now decided, put back a real
185			 * hyphen such that we get the correct width.
186			 */
187			if (p->tcol->buf[j] == ASCII_HYPH)
188				p->tcol->buf[j] = '-';
189
190			vend += (*p->width)(p, p->tcol->buf[j]);
191		}
192
193		/*
194		 * Find out whether we would exceed the right margin.
195		 * If so, break to the next line.
196		 */
197
198		if (vend > bp && jhy == 0 && vis > 0 &&
199		    (p->flags & TERMP_BRNEVER) == 0) {
200			if (p->flags & TERMP_MULTICOL)
201				return;
202
203			endline(p);
204			vend -= vis;
205
206			/* Use pending tabs on the new line. */
207
208			vbl = 0;
209			while (ntab--)
210				vbl = term_tab_next(vbl);
211
212			/* Re-establish indentation. */
213
214			if (p->flags & TERMP_BRIND)
215				vbl += p->tcol->rmargin;
216			else
217				vbl += p->tcol->offset;
218			maxvis = p->tcol->rmargin > vbl ?
219			    p->tcol->rmargin - vbl : 0;
220			bp = !(p->flags & TERMP_NOBREAK) ? maxvis :
221			    p->maxrmargin > vbl ?  p->maxrmargin - vbl : 0;
222		}
223
224		/*
225		 * Write out the rest of the word.
226		 */
227
228		for ( ; p->tcol->col < p->tcol->lastcol; p->tcol->col++) {
229			if (vend > bp && jhy > 0 && p->tcol->col > jhy)
230				break;
231			if (p->tcol->buf[p->tcol->col] == '\n')
232				continue;
233			if (p->tcol->buf[p->tcol->col] == '\t')
234				break;
235			if (p->tcol->buf[p->tcol->col] == ' ') {
236				j = p->tcol->col;
237				while (p->tcol->col < p->tcol->lastcol &&
238				    p->tcol->buf[p->tcol->col] == ' ')
239					p->tcol->col++;
240				dv = (p->tcol->col - j) * (*p->width)(p, ' ');
241				vbl += dv;
242				vend += dv;
243				break;
244			}
245			if (p->tcol->buf[p->tcol->col] == ASCII_NBRSP) {
246				vbl += (*p->width)(p, ' ');
247				continue;
248			}
249			if (p->tcol->buf[p->tcol->col] == ASCII_BREAK)
250				continue;
251
252			/*
253			 * Now we definitely know there will be
254			 * printable characters to output,
255			 * so write preceding white space now.
256			 */
257			if (vbl) {
258				(*p->advance)(p, vbl);
259				p->viscol += vbl;
260				vbl = 0;
261			}
262
263			(*p->letter)(p, p->tcol->buf[p->tcol->col]);
264			if (p->tcol->buf[p->tcol->col] == '\b')
265				p->viscol -= (*p->width)(p,
266				    p->tcol->buf[p->tcol->col - 1]);
267			else
268				p->viscol += (*p->width)(p,
269				    p->tcol->buf[p->tcol->col]);
270		}
271		vis = vend;
272
273		if (breakline == 0)
274			continue;
275
276		/* Explicitly requested output line break. */
277
278		if (p->flags & TERMP_MULTICOL)
279			return;
280
281		endline(p);
282		breakline = 0;
283		vis = vend = 0;
284
285		/* Re-establish indentation. */
286
287		vbl = p->tcol->offset;
288		maxvis = p->tcol->rmargin > vbl ?
289		    p->tcol->rmargin - vbl : 0;
290		bp = !(p->flags & TERMP_NOBREAK) ? maxvis :
291		    p->maxrmargin > vbl ?  p->maxrmargin - vbl : 0;
292	}
293
294	/*
295	 * If there was trailing white space, it was not printed;
296	 * so reset the cursor position accordingly.
297	 */
298
299	if (vis > vbl)
300		vis -= vbl;
301	else
302		vis = 0;
303
304	p->col = p->tcol->col = p->tcol->lastcol = 0;
305	p->minbl = p->trailspace;
306	p->flags &= ~(TERMP_BACKAFTER | TERMP_BACKBEFORE | TERMP_NOPAD);
307
308	if (p->flags & TERMP_MULTICOL)
309		return;
310
311	/* Trailing whitespace is significant in some columns. */
312
313	if (vis && vbl && (TERMP_BRTRSP & p->flags))
314		vis += vbl;
315
316	/* If the column was overrun, break the line. */
317	if ((p->flags & TERMP_NOBREAK) == 0 ||
318	    ((p->flags & TERMP_HANG) == 0 &&
319	     vis + p->trailspace * (*p->width)(p, ' ') > maxvis))
320		endline(p);
321}
322
323static void
324endline(struct termp *p)
325{
326	if ((p->flags & (TERMP_NEWMC | TERMP_ENDMC)) == TERMP_ENDMC) {
327		p->mc = NULL;
328		p->flags &= ~TERMP_ENDMC;
329	}
330	if (p->mc != NULL) {
331		if (p->viscol && p->maxrmargin >= p->viscol)
332			(*p->advance)(p, p->maxrmargin - p->viscol + 1);
333		p->flags |= TERMP_NOBUF | TERMP_NOSPACE;
334		term_word(p, p->mc);
335		p->flags &= ~(TERMP_NOBUF | TERMP_NEWMC);
336	}
337	p->viscol = 0;
338	p->minbl = 0;
339	(*p->endline)(p);
340}
341
342/*
343 * A newline only breaks an existing line; it won't assert vertical
344 * space.  All data in the output buffer is flushed prior to the newline
345 * assertion.
346 */
347void
348term_newln(struct termp *p)
349{
350
351	p->flags |= TERMP_NOSPACE;
352	if (p->tcol->lastcol || p->viscol)
353		term_flushln(p);
354}
355
356/*
357 * Asserts a vertical space (a full, empty line-break between lines).
358 * Note that if used twice, this will cause two blank spaces and so on.
359 * All data in the output buffer is flushed prior to the newline
360 * assertion.
361 */
362void
363term_vspace(struct termp *p)
364{
365
366	term_newln(p);
367	p->viscol = 0;
368	p->minbl = 0;
369	if (0 < p->skipvsp)
370		p->skipvsp--;
371	else
372		(*p->endline)(p);
373}
374
375/* Swap current and previous font; for \fP and .ft P */
376void
377term_fontlast(struct termp *p)
378{
379	enum termfont	 f;
380
381	f = p->fontl;
382	p->fontl = p->fontq[p->fonti];
383	p->fontq[p->fonti] = f;
384}
385
386/* Set font, save current, discard previous; for \f, .ft, .B etc. */
387void
388term_fontrepl(struct termp *p, enum termfont f)
389{
390
391	p->fontl = p->fontq[p->fonti];
392	p->fontq[p->fonti] = f;
393}
394
395/* Set font, save previous. */
396void
397term_fontpush(struct termp *p, enum termfont f)
398{
399
400	p->fontl = p->fontq[p->fonti];
401	if (++p->fonti == p->fontsz) {
402		p->fontsz += 8;
403		p->fontq = mandoc_reallocarray(p->fontq,
404		    p->fontsz, sizeof(*p->fontq));
405	}
406	p->fontq[p->fonti] = f;
407}
408
409/* Flush to make the saved pointer current again. */
410void
411term_fontpopq(struct termp *p, int i)
412{
413
414	assert(i >= 0);
415	if (p->fonti > i)
416		p->fonti = i;
417}
418
419/* Pop one font off the stack. */
420void
421term_fontpop(struct termp *p)
422{
423
424	assert(p->fonti);
425	p->fonti--;
426}
427
428/*
429 * Handle pwords, partial words, which may be either a single word or a
430 * phrase that cannot be broken down (such as a literal string).  This
431 * handles word styling.
432 */
433void
434term_word(struct termp *p, const char *word)
435{
436	struct roffsu	 su;
437	const char	 nbrsp[2] = { ASCII_NBRSP, 0 };
438	const char	*seq, *cp;
439	int		 sz, uc;
440	size_t		 csz, lsz, ssz;
441	enum mandoc_esc	 esc;
442
443	if ((p->flags & TERMP_NOBUF) == 0) {
444		if ((p->flags & TERMP_NOSPACE) == 0) {
445			if ((p->flags & TERMP_KEEP) == 0) {
446				bufferc(p, ' ');
447				if (p->flags & TERMP_SENTENCE)
448					bufferc(p, ' ');
449			} else
450				bufferc(p, ASCII_NBRSP);
451		}
452		if (p->flags & TERMP_PREKEEP)
453			p->flags |= TERMP_KEEP;
454		if (p->flags & TERMP_NONOSPACE)
455			p->flags |= TERMP_NOSPACE;
456		else
457			p->flags &= ~TERMP_NOSPACE;
458		p->flags &= ~(TERMP_SENTENCE | TERMP_NONEWLINE);
459		p->skipvsp = 0;
460	}
461
462	while ('\0' != *word) {
463		if ('\\' != *word) {
464			if (TERMP_NBRWORD & p->flags) {
465				if (' ' == *word) {
466					encode(p, nbrsp, 1);
467					word++;
468					continue;
469				}
470				ssz = strcspn(word, "\\ ");
471			} else
472				ssz = strcspn(word, "\\");
473			encode(p, word, ssz);
474			word += (int)ssz;
475			continue;
476		}
477
478		word++;
479		esc = mandoc_escape(&word, &seq, &sz);
480		if (ESCAPE_ERROR == esc)
481			continue;
482
483		switch (esc) {
484		case ESCAPE_UNICODE:
485			uc = mchars_num2uc(seq + 1, sz - 1);
486			break;
487		case ESCAPE_NUMBERED:
488			uc = mchars_num2char(seq, sz);
489			if (uc < 0)
490				continue;
491			break;
492		case ESCAPE_SPECIAL:
493			if (p->enc == TERMENC_ASCII) {
494				cp = mchars_spec2str(seq, sz, &ssz);
495				if (cp != NULL)
496					encode(p, cp, ssz);
497			} else {
498				uc = mchars_spec2cp(seq, sz);
499				if (uc > 0)
500					encode1(p, uc);
501			}
502			continue;
503		case ESCAPE_FONTBOLD:
504			term_fontrepl(p, TERMFONT_BOLD);
505			continue;
506		case ESCAPE_FONTITALIC:
507			term_fontrepl(p, TERMFONT_UNDER);
508			continue;
509		case ESCAPE_FONTBI:
510			term_fontrepl(p, TERMFONT_BI);
511			continue;
512		case ESCAPE_FONT:
513		case ESCAPE_FONTROMAN:
514			term_fontrepl(p, TERMFONT_NONE);
515			continue;
516		case ESCAPE_FONTPREV:
517			term_fontlast(p);
518			continue;
519		case ESCAPE_BREAK:
520			bufferc(p, '\n');
521			continue;
522		case ESCAPE_NOSPACE:
523			if (p->flags & TERMP_BACKAFTER)
524				p->flags &= ~TERMP_BACKAFTER;
525			else if (*word == '\0')
526				p->flags |= (TERMP_NOSPACE | TERMP_NONEWLINE);
527			continue;
528		case ESCAPE_HORIZ:
529			if (*seq == '|') {
530				seq++;
531				uc = -p->col;
532			} else
533				uc = 0;
534			if (a2roffsu(seq, &su, SCALE_EM) == NULL)
535				continue;
536			uc += term_hen(p, &su);
537			if (uc > 0)
538				while (uc-- > 0)
539					bufferc(p, ASCII_NBRSP);
540			else if (p->col > (size_t)(-uc))
541				p->col += uc;
542			else {
543				uc += p->col;
544				p->col = 0;
545				if (p->tcol->offset > (size_t)(-uc)) {
546					p->ti += uc;
547					p->tcol->offset += uc;
548				} else {
549					p->ti -= p->tcol->offset;
550					p->tcol->offset = 0;
551				}
552			}
553			continue;
554		case ESCAPE_HLINE:
555			if ((cp = a2roffsu(seq, &su, SCALE_EM)) == NULL)
556				continue;
557			uc = term_hen(p, &su);
558			if (uc <= 0) {
559				if (p->tcol->rmargin <= p->tcol->offset)
560					continue;
561				lsz = p->tcol->rmargin - p->tcol->offset;
562			} else
563				lsz = uc;
564			if (*cp == seq[-1])
565				uc = -1;
566			else if (*cp == '\\') {
567				seq = cp + 1;
568				esc = mandoc_escape(&seq, &cp, &sz);
569				switch (esc) {
570				case ESCAPE_UNICODE:
571					uc = mchars_num2uc(cp + 1, sz - 1);
572					break;
573				case ESCAPE_NUMBERED:
574					uc = mchars_num2char(cp, sz);
575					break;
576				case ESCAPE_SPECIAL:
577					uc = mchars_spec2cp(cp, sz);
578					break;
579				default:
580					uc = -1;
581					break;
582				}
583			} else
584				uc = *cp;
585			if (uc < 0x20 || (uc > 0x7E && uc < 0xA0))
586				uc = '_';
587			if (p->enc == TERMENC_ASCII) {
588				cp = ascii_uc2str(uc);
589				csz = term_strlen(p, cp);
590				ssz = strlen(cp);
591			} else
592				csz = (*p->width)(p, uc);
593			while (lsz >= csz) {
594				if (p->enc == TERMENC_ASCII)
595					encode(p, cp, ssz);
596				else
597					encode1(p, uc);
598				lsz -= csz;
599			}
600			continue;
601		case ESCAPE_SKIPCHAR:
602			p->flags |= TERMP_BACKAFTER;
603			continue;
604		case ESCAPE_OVERSTRIKE:
605			cp = seq + sz;
606			while (seq < cp) {
607				if (*seq == '\\') {
608					mandoc_escape(&seq, NULL, NULL);
609					continue;
610				}
611				encode1(p, *seq++);
612				if (seq < cp) {
613					if (p->flags & TERMP_BACKBEFORE)
614						p->flags |= TERMP_BACKAFTER;
615					else
616						p->flags |= TERMP_BACKBEFORE;
617				}
618			}
619			/* Trim trailing backspace/blank pair. */
620			if (p->tcol->lastcol > 2 &&
621			    (p->tcol->buf[p->tcol->lastcol - 1] == ' ' ||
622			     p->tcol->buf[p->tcol->lastcol - 1] == '\t'))
623				p->tcol->lastcol -= 2;
624			if (p->col > p->tcol->lastcol)
625				p->col = p->tcol->lastcol;
626			continue;
627		default:
628			continue;
629		}
630
631		/*
632		 * Common handling for Unicode and numbered
633		 * character escape sequences.
634		 */
635
636		if (p->enc == TERMENC_ASCII) {
637			cp = ascii_uc2str(uc);
638			encode(p, cp, strlen(cp));
639		} else {
640			if ((uc < 0x20 && uc != 0x09) ||
641			    (uc > 0x7E && uc < 0xA0))
642				uc = 0xFFFD;
643			encode1(p, uc);
644		}
645	}
646	p->flags &= ~TERMP_NBRWORD;
647}
648
649static void
650adjbuf(struct termp_col *c, size_t sz)
651{
652	if (c->maxcols == 0)
653		c->maxcols = 1024;
654	while (c->maxcols <= sz)
655		c->maxcols <<= 2;
656	c->buf = mandoc_reallocarray(c->buf, c->maxcols, sizeof(*c->buf));
657}
658
659static void
660bufferc(struct termp *p, char c)
661{
662	if (p->flags & TERMP_NOBUF) {
663		(*p->letter)(p, c);
664		return;
665	}
666	if (p->col + 1 >= p->tcol->maxcols)
667		adjbuf(p->tcol, p->col + 1);
668	if (p->tcol->lastcol <= p->col || (c != ' ' && c != ASCII_NBRSP))
669		p->tcol->buf[p->col] = c;
670	if (p->tcol->lastcol < ++p->col)
671		p->tcol->lastcol = p->col;
672}
673
674/*
675 * See encode().
676 * Do this for a single (probably unicode) value.
677 * Does not check for non-decorated glyphs.
678 */
679static void
680encode1(struct termp *p, int c)
681{
682	enum termfont	  f;
683
684	if (p->flags & TERMP_NOBUF) {
685		(*p->letter)(p, c);
686		return;
687	}
688
689	if (p->col + 7 >= p->tcol->maxcols)
690		adjbuf(p->tcol, p->col + 7);
691
692	f = (c == ASCII_HYPH || c > 127 || isgraph(c)) ?
693	    p->fontq[p->fonti] : TERMFONT_NONE;
694
695	if (p->flags & TERMP_BACKBEFORE) {
696		if (p->tcol->buf[p->col - 1] == ' ' ||
697		    p->tcol->buf[p->col - 1] == '\t')
698			p->col--;
699		else
700			p->tcol->buf[p->col++] = '\b';
701		p->flags &= ~TERMP_BACKBEFORE;
702	}
703	if (f == TERMFONT_UNDER || f == TERMFONT_BI) {
704		p->tcol->buf[p->col++] = '_';
705		p->tcol->buf[p->col++] = '\b';
706	}
707	if (f == TERMFONT_BOLD || f == TERMFONT_BI) {
708		if (c == ASCII_HYPH)
709			p->tcol->buf[p->col++] = '-';
710		else
711			p->tcol->buf[p->col++] = c;
712		p->tcol->buf[p->col++] = '\b';
713	}
714	if (p->tcol->lastcol <= p->col || (c != ' ' && c != ASCII_NBRSP))
715		p->tcol->buf[p->col] = c;
716	if (p->tcol->lastcol < ++p->col)
717		p->tcol->lastcol = p->col;
718	if (p->flags & TERMP_BACKAFTER) {
719		p->flags |= TERMP_BACKBEFORE;
720		p->flags &= ~TERMP_BACKAFTER;
721	}
722}
723
724static void
725encode(struct termp *p, const char *word, size_t sz)
726{
727	size_t		  i;
728
729	if (p->flags & TERMP_NOBUF) {
730		for (i = 0; i < sz; i++)
731			(*p->letter)(p, word[i]);
732		return;
733	}
734
735	if (p->col + 2 + (sz * 5) >= p->tcol->maxcols)
736		adjbuf(p->tcol, p->col + 2 + (sz * 5));
737
738	for (i = 0; i < sz; i++) {
739		if (ASCII_HYPH == word[i] ||
740		    isgraph((unsigned char)word[i]))
741			encode1(p, word[i]);
742		else {
743			if (p->tcol->lastcol <= p->col ||
744			    (word[i] != ' ' && word[i] != ASCII_NBRSP))
745				p->tcol->buf[p->col] = word[i];
746			p->col++;
747
748			/*
749			 * Postpone the effect of \z while handling
750			 * an overstrike sequence from ascii_uc2str().
751			 */
752
753			if (word[i] == '\b' &&
754			    (p->flags & TERMP_BACKBEFORE)) {
755				p->flags &= ~TERMP_BACKBEFORE;
756				p->flags |= TERMP_BACKAFTER;
757			}
758		}
759	}
760	if (p->tcol->lastcol < p->col)
761		p->tcol->lastcol = p->col;
762}
763
764void
765term_setwidth(struct termp *p, const char *wstr)
766{
767	struct roffsu	 su;
768	int		 iop, width;
769
770	iop = 0;
771	width = 0;
772	if (NULL != wstr) {
773		switch (*wstr) {
774		case '+':
775			iop = 1;
776			wstr++;
777			break;
778		case '-':
779			iop = -1;
780			wstr++;
781			break;
782		default:
783			break;
784		}
785		if (a2roffsu(wstr, &su, SCALE_MAX) != NULL)
786			width = term_hspan(p, &su);
787		else
788			iop = 0;
789	}
790	(*p->setwidth)(p, iop, width);
791}
792
793size_t
794term_len(const struct termp *p, size_t sz)
795{
796
797	return (*p->width)(p, ' ') * sz;
798}
799
800static size_t
801cond_width(const struct termp *p, int c, int *skip)
802{
803
804	if (*skip) {
805		(*skip) = 0;
806		return 0;
807	} else
808		return (*p->width)(p, c);
809}
810
811size_t
812term_strlen(const struct termp *p, const char *cp)
813{
814	size_t		 sz, rsz, i;
815	int		 ssz, skip, uc;
816	const char	*seq, *rhs;
817	enum mandoc_esc	 esc;
818	static const char rej[] = { '\\', ASCII_NBRSP, ASCII_HYPH,
819			ASCII_BREAK, '\0' };
820
821	/*
822	 * Account for escaped sequences within string length
823	 * calculations.  This follows the logic in term_word() as we
824	 * must calculate the width of produced strings.
825	 */
826
827	sz = 0;
828	skip = 0;
829	while ('\0' != *cp) {
830		rsz = strcspn(cp, rej);
831		for (i = 0; i < rsz; i++)
832			sz += cond_width(p, *cp++, &skip);
833
834		switch (*cp) {
835		case '\\':
836			cp++;
837			esc = mandoc_escape(&cp, &seq, &ssz);
838			if (ESCAPE_ERROR == esc)
839				continue;
840
841			rhs = NULL;
842
843			switch (esc) {
844			case ESCAPE_UNICODE:
845				uc = mchars_num2uc(seq + 1, ssz - 1);
846				break;
847			case ESCAPE_NUMBERED:
848				uc = mchars_num2char(seq, ssz);
849				if (uc < 0)
850					continue;
851				break;
852			case ESCAPE_SPECIAL:
853				if (p->enc == TERMENC_ASCII) {
854					rhs = mchars_spec2str(seq, ssz, &rsz);
855					if (rhs != NULL)
856						break;
857				} else {
858					uc = mchars_spec2cp(seq, ssz);
859					if (uc > 0)
860						sz += cond_width(p, uc, &skip);
861				}
862				continue;
863			case ESCAPE_SKIPCHAR:
864				skip = 1;
865				continue;
866			case ESCAPE_OVERSTRIKE:
867				rsz = 0;
868				rhs = seq + ssz;
869				while (seq < rhs) {
870					if (*seq == '\\') {
871						mandoc_escape(&seq, NULL, NULL);
872						continue;
873					}
874					i = (*p->width)(p, *seq++);
875					if (rsz < i)
876						rsz = i;
877				}
878				sz += rsz;
879				continue;
880			default:
881				continue;
882			}
883
884			/*
885			 * Common handling for Unicode and numbered
886			 * character escape sequences.
887			 */
888
889			if (rhs == NULL) {
890				if (p->enc == TERMENC_ASCII) {
891					rhs = ascii_uc2str(uc);
892					rsz = strlen(rhs);
893				} else {
894					if ((uc < 0x20 && uc != 0x09) ||
895					    (uc > 0x7E && uc < 0xA0))
896						uc = 0xFFFD;
897					sz += cond_width(p, uc, &skip);
898					continue;
899				}
900			}
901
902			if (skip) {
903				skip = 0;
904				break;
905			}
906
907			/*
908			 * Common handling for all escape sequences
909			 * printing more than one character.
910			 */
911
912			for (i = 0; i < rsz; i++)
913				sz += (*p->width)(p, *rhs++);
914			break;
915		case ASCII_NBRSP:
916			sz += cond_width(p, ' ', &skip);
917			cp++;
918			break;
919		case ASCII_HYPH:
920			sz += cond_width(p, '-', &skip);
921			cp++;
922			break;
923		default:
924			break;
925		}
926	}
927
928	return sz;
929}
930
931int
932term_vspan(const struct termp *p, const struct roffsu *su)
933{
934	double		 r;
935	int		 ri;
936
937	switch (su->unit) {
938	case SCALE_BU:
939		r = su->scale / 40.0;
940		break;
941	case SCALE_CM:
942		r = su->scale * 6.0 / 2.54;
943		break;
944	case SCALE_FS:
945		r = su->scale * 65536.0 / 40.0;
946		break;
947	case SCALE_IN:
948		r = su->scale * 6.0;
949		break;
950	case SCALE_MM:
951		r = su->scale * 0.006;
952		break;
953	case SCALE_PC:
954		r = su->scale;
955		break;
956	case SCALE_PT:
957		r = su->scale / 12.0;
958		break;
959	case SCALE_EN:
960	case SCALE_EM:
961		r = su->scale * 0.6;
962		break;
963	case SCALE_VS:
964		r = su->scale;
965		break;
966	default:
967		abort();
968	}
969	ri = r > 0.0 ? r + 0.4995 : r - 0.4995;
970	return ri < 66 ? ri : 1;
971}
972
973/*
974 * Convert a scaling width to basic units, rounding towards 0.
975 */
976int
977term_hspan(const struct termp *p, const struct roffsu *su)
978{
979
980	return (*p->hspan)(p, su);
981}
982
983/*
984 * Convert a scaling width to basic units, rounding to closest.
985 */
986int
987term_hen(const struct termp *p, const struct roffsu *su)
988{
989	int bu;
990
991	if ((bu = (*p->hspan)(p, su)) >= 0)
992		return (bu + 11) / 24;
993	else
994		return -((-bu + 11) / 24);
995}
996