===================================================================
RCS file: /cvs/mandoc/term.c,v
retrieving revision 1.248
retrieving revision 1.261
diff -u -p -r1.248 -r1.261
--- mandoc/term.c	2015/04/29 18:35:00	1.248
+++ mandoc/term.c	2017/06/01 19:05:37	1.261
@@ -1,7 +1,7 @@
-/*	$Id: term.c,v 1.248 2015/04/29 18:35:00 schwarze Exp $ */
+/*	$Id: term.c,v 1.261 2017/06/01 19:05:37 schwarze Exp $ */
 /*
  * Copyright (c) 2008, 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
- * Copyright (c) 2010-2015 Ingo Schwarze <schwarze@openbsd.org>
+ * Copyright (c) 2010-2017 Ingo Schwarze <schwarze@openbsd.org>
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -78,6 +78,8 @@ term_end(struct termp *p)
  *    the next column.  However, if less than p->trailspace blanks,
  *    which can be 0, 1, or 2, remain to the right margin, the line
  *    will be broken.
+ *  - TERMP_BRTRSP: Consider trailing whitespace significant
+ *    when deciding whether the chunk fits or not.
  *  - TERMP_BRIND: If the chunk does not fit and the output line has
  *    to be broken, start the next line at the right margin instead
  *    of at the offset.  Used together with TERMP_NOBREAK for the tags
@@ -139,8 +141,8 @@ term_flushln(struct termp *p)
 		 * subsequent tabs into a single huge set of spaces.
 		 */
 		ntab = 0;
-		while (i < p->col && '\t' == p->buf[i]) {
-			vend = (vis / p->tabwidth + 1) * p->tabwidth;
+		while (i < p->col && p->buf[i] == '\t') {
+			vend = term_tab_next(vis);
 			vbl += vend - vis;
 			vis = vend;
 			ntab++;
@@ -158,7 +160,7 @@ term_flushln(struct termp *p)
 			if (' ' == p->buf[j] || '\t' == p->buf[j])
 				break;
 
-			/* Back over the the last printed character. */
+			/* Back over the last printed character. */
 			if (8 == p->buf[j]) {
 				assert(j);
 				vend -= (*p->width)(p, p->buf[j - 1]);
@@ -190,18 +192,21 @@ term_flushln(struct termp *p)
 			vend -= vis;
 			(*p->endline)(p);
 			p->viscol = 0;
-			if (TERMP_BRIND & p->flags) {
-				vbl = p->rmargin;
-				vend += p->rmargin;
-				vend -= p->offset;
-			} else
-				vbl = p->offset;
 
-			/* use pending tabs on the new line */
+			/* Use pending tabs on the new line. */
 
-			if (0 < ntab)
-				vbl += ntab * p->tabwidth;
+			vbl = 0;
+			while (ntab--)
+				vbl = term_tab_next(vbl);
 
+			/* Re-establish indentation. */
+
+			if (p->flags & TERMP_BRIND) {
+				vbl += p->rmargin;
+				vend += p->rmargin - p->offset;
+			} else
+				vbl += p->offset;
+
 			/*
 			 * Remove the p->overstep width.
 			 * Again, if p->overstep is negative,
@@ -291,6 +296,10 @@ term_flushln(struct termp *p)
 	} else if (TERMP_DANGLE & p->flags)
 		return;
 
+	/* Trailing whitespace is significant in some columns. */
+	if (vis && vbl && (TERMP_BRTRSP & p->flags))
+		vis += vbl;
+
 	/* If the column was overrun, break the line. */
 	if (maxvis < vis + p->trailspace * (*p->width)(p, ' ')) {
 		(*p->endline)(p);
@@ -359,7 +368,7 @@ term_fontpush(struct termp *p, enum termfont f)
 	if (++p->fonti == p->fontsz) {
 		p->fontsz += 8;
 		p->fontq = mandoc_reallocarray(p->fontq,
-		    p->fontsz, sizeof(enum termfont *));
+		    p->fontsz, sizeof(*p->fontq));
 	}
 	p->fontq[p->fonti] = f;
 }
@@ -391,6 +400,7 @@ term_fontpop(struct termp *p)
 void
 term_word(struct termp *p, const char *word)
 {
+	struct roffsu	 su;
 	const char	 nbrsp[2] = { ASCII_NBRSP, 0 };
 	const char	*seq, *cp;
 	int		 sz, uc;
@@ -448,12 +458,11 @@ term_word(struct termp *p, const char *word)
 			break;
 		case ESCAPE_SPECIAL:
 			if (p->enc == TERMENC_ASCII) {
-				cp = mchars_spec2str(p->symtab,
-				    seq, sz, &ssz);
+				cp = mchars_spec2str(seq, sz, &ssz);
 				if (cp != NULL)
 					encode(p, cp, ssz);
 			} else {
-				uc = mchars_spec2cp(p->symtab, seq, sz);
+				uc = mchars_spec2cp(seq, sz);
 				if (uc > 0)
 					encode1(p, uc);
 			}
@@ -468,7 +477,6 @@ term_word(struct termp *p, const char *word)
 			term_fontrepl(p, TERMFONT_BI);
 			continue;
 		case ESCAPE_FONT:
-			/* FALLTHROUGH */
 		case ESCAPE_FONTROMAN:
 			term_fontrepl(p, TERMFONT_NONE);
 			continue;
@@ -481,6 +489,27 @@ term_word(struct termp *p, const char *word)
 			else if (*word == '\0')
 				p->flags |= (TERMP_NOSPACE | TERMP_NONEWLINE);
 			continue;
+		case ESCAPE_HORIZ:
+			if (a2roffsu(seq, &su, SCALE_EM) == 0)
+				continue;
+			uc = term_hspan(p, &su) / 24;
+			if (uc > 0)
+				while (uc-- > 0)
+					bufferc(p, ASCII_NBRSP);
+			else if (p->col > (size_t)(-uc))
+				p->col += uc;
+			else {
+				uc += p->col;
+				p->col = 0;
+				if (p->offset > (size_t)(-uc)) {
+					p->ti += uc;
+					p->offset += uc;
+				} else {
+					p->ti -= p->offset;
+					p->offset = 0;
+				}
+			}
+			continue;
 		case ESCAPE_SKIPCHAR:
 			p->flags |= TERMP_BACKAFTER;
 			continue;
@@ -499,6 +528,11 @@ term_word(struct termp *p, const char *word)
 						p->flags |= TERMP_BACKBEFORE;
 				}
 			}
+			/* Trim trailing backspace/blank pair. */
+			if (p->col > 2 &&
+			    (p->buf[p->col - 1] == ' ' ||
+			     p->buf[p->col - 1] == '\t'))
+				p->col -= 2;
 			continue;
 		default:
 			continue;
@@ -557,11 +591,14 @@ encode1(struct termp *p, int c)
 	if (p->col + 7 >= p->maxcols)
 		adjbuf(p, p->col + 7);
 
-	f = (c == ASCII_HYPH || isgraph(c)) ?
+	f = (c == ASCII_HYPH || c > 127 || isgraph(c)) ?
 	    p->fontq[p->fonti] : TERMFONT_NONE;
 
 	if (p->flags & TERMP_BACKBEFORE) {
-		p->buf[p->col++] = 8;
+		if (p->buf[p->col - 1] == ' ' || p->buf[p->col - 1] == '\t')
+			p->col--;
+		else
+			p->buf[p->col++] = 8;
 		p->flags &= ~TERMP_BACKBEFORE;
 	}
 	if (TERMFONT_UNDER == f || TERMFONT_BI == f) {
@@ -594,8 +631,20 @@ encode(struct termp *p, const char *word, size_t sz)
 		if (ASCII_HYPH == word[i] ||
 		    isgraph((unsigned char)word[i]))
 			encode1(p, word[i]);
-		else
+		else {
 			p->buf[p->col++] = word[i];
+
+			/*
+			 * Postpone the effect of \z while handling
+			 * an overstrike sequence from ascii_uc2str().
+			 */
+
+			if (word[i] == '\b' &&
+			    (p->flags & TERMP_BACKBEFORE)) {
+				p->flags &= ~TERMP_BACKBEFORE;
+				p->flags |= TERMP_BACKAFTER;
+			}
+		}
 	}
 }
 
@@ -632,7 +681,7 @@ size_t
 term_len(const struct termp *p, size_t sz)
 {
 
-	return((*p->width)(p, ' ') * sz);
+	return (*p->width)(p, ' ') * sz;
 }
 
 static size_t
@@ -641,9 +690,9 @@ cond_width(const struct termp *p, int c, int *skip)
 
 	if (*skip) {
 		(*skip) = 0;
-		return(0);
+		return 0;
 	} else
-		return((*p->width)(p, c));
+		return (*p->width)(p, c);
 }
 
 size_t
@@ -689,13 +738,11 @@ term_strlen(const struct termp *p, const char *cp)
 				break;
 			case ESCAPE_SPECIAL:
 				if (p->enc == TERMENC_ASCII) {
-					rhs = mchars_spec2str(p->symtab,
-					    seq, ssz, &rsz);
+					rhs = mchars_spec2str(seq, ssz, &rsz);
 					if (rhs != NULL)
 						break;
 				} else {
-					uc = mchars_spec2cp(p->symtab,
-					    seq, ssz);
+					uc = mchars_spec2cp(seq, ssz);
 					if (uc > 0)
 						sz += cond_width(p, uc, &skip);
 				}
@@ -759,15 +806,13 @@ term_strlen(const struct termp *p, const char *cp)
 		case ASCII_HYPH:
 			sz += cond_width(p, '-', &skip);
 			cp++;
-			/* FALLTHROUGH */
-		case ASCII_BREAK:
 			break;
 		default:
 			break;
 		}
 	}
 
-	return(sz);
+	return sz;
 }
 
 int
@@ -799,7 +844,6 @@ term_vspan(const struct termp *p, const struct roffsu 
 		r = su->scale / 12.0;
 		break;
 	case SCALE_EN:
-		/* FALLTHROUGH */
 	case SCALE_EM:
 		r = su->scale * 0.6;
 		break;
@@ -808,10 +852,9 @@ term_vspan(const struct termp *p, const struct roffsu 
 		break;
 	default:
 		abort();
-		/* NOTREACHED */
 	}
 	ri = r > 0.0 ? r + 0.4995 : r - 0.4995;
-	return(ri < 66 ? ri : 1);
+	return ri < 66 ? ri : 1;
 }
 
 /*
@@ -821,5 +864,5 @@ int
 term_hspan(const struct termp *p, const struct roffsu *su)
 {
 
-	return((*p->hspan)(p, su));
+	return (*p->hspan)(p, su);
 }