support negative horizontal widths in man(7);

minus twenty lines of code in spite of enhanced functionality

7 files changed, 93 insertions, 129 deletions

diff --git a/man_term.c b/man_term.c
index 03456b2b..4652cd18 100644
--- a/man_term.c
+++ b/man_term.c
@@ -37,7 +37,7 @@
 struct	mtermp {
 	int		  fl;
 #define	MANT_LITERAL	 (1 << 0)
-	size_t		  lmargin[MAXMARGINS]; /* margins (incl. visible page) */
+	int		  lmargin[MAXMARGINS]; /* margins (incl. vis. page) */
 	int		  lmargincur; /* index of current margin */
 	int		  lmarginsz; /* actual number of nested margins */
 	size_t		  offset; /* default offset to visible page */
@@ -56,8 +56,6 @@ struct	termact {
 #define	MAN_NOTEXT	 (1 << 0) /* Never has text children. */
 };
 
-static	int		  a2width(const struct termp *, const char *);
-
 static	void		  print_man_nodelist(DECL_ARGS);
 static	void		  print_man_node(DECL_ARGS);
 static	void		  print_man_head(struct termp *, const void *);
@@ -183,17 +181,6 @@ terminal_man(void *arg, const struct man *man)
 	}
 }
 
-static int
-a2width(const struct termp *p, const char *cp)
-{
-	struct roffsu	 su;
-
-	if ( ! a2roffsu(cp, &su, SCALE_EN))
-		return(-1);
-
-	return((int)term_hspan(p, &su));
-}
-
 /*
  * Printing leading vertical space before a block.
  * This is used for the paragraph macros.
@@ -412,9 +399,10 @@ pre_ft(DECL_ARGS)
 static int
 pre_in(DECL_ARGS)
 {
-	int		 len, less;
-	size_t		 v;
+	struct roffsu	 su;
 	const char	*cp;
+	size_t		 v;
+	int		 less;
 
 	term_newln(p);
 
@@ -433,10 +421,10 @@ pre_in(DECL_ARGS)
 	else
 		cp--;
 
-	if ((len = a2width(p, ++cp)) < 0)
+	if ( ! a2roffsu(++cp, &su, SCALE_EN))
 		return(0);
 
-	v = (size_t)len;
+	v = term_hspan(p, &su);
 
 	if (less < 0)
 		p->offset -= p->offset > v ? v : p->offset;
@@ -452,9 +440,7 @@ static int
 pre_sp(DECL_ARGS)
 {
 	struct roffsu	 su;
-	char		*s;
-	size_t		 i, len;
-	int		 neg;
+	int		 i, len;
 
 	if ((NULL == n->prev && n->parent)) {
 		switch (n->parent->tok) {
@@ -474,31 +460,20 @@ pre_sp(DECL_ARGS)
 		}
 	}
 
-	neg = 0;
-	switch (n->tok) {
-	case MAN_br:
+	if (n->tok == MAN_br)
 		len = 0;
-		break;
-	default:
-		if (NULL == n->child) {
-			len = 1;
-			break;
-		}
-		s = n->child->string;
-		if ('-' == *s) {
-			neg = 1;
-			s++;
-		}
-		if ( ! a2roffsu(s, &su, SCALE_VS))
+	else if (n->child == NULL)
+		len = 1;
+	else {
+		if ( ! a2roffsu(n->child->string, &su, SCALE_VS))
 			su.scale = 1.0;
 		len = term_vspan(p, &su);
-		break;
 	}
 
-	if (0 == len)
+	if (len == 0)
 		term_newln(p);
-	else if (neg)
-		p->skipvsp += len;
+	else if (len < 0)
+		p->skipvsp -= len;
 	else
 		for (i = 0; i < len; i++)
 			term_vspace(p);
@@ -509,9 +484,9 @@ pre_sp(DECL_ARGS)
 static int
 pre_HP(DECL_ARGS)
 {
-	size_t			 len, one;
-	int			 ival;
+	struct roffsu		 su;
 	const struct man_node	*nn;
+	int			 len;
 
 	switch (n->type) {
 	case MAN_BLOCK:
@@ -528,24 +503,20 @@ pre_HP(DECL_ARGS)
 		p->trailspace = 2;
 	}
 
-	len = mt->lmargin[mt->lmargincur];
-	ival = -1;
-
 	/* Calculate offset. */
 
-	if (NULL != (nn = n->parent->head->child))
-		if ((ival = a2width(p, nn->string)) >= 0)
-			len = (size_t)ival;
-
-	one = term_len(p, 1);
-	if (len < one)
-		len = one;
+	if ((nn = n->parent->head->child) != NULL &&
+	    a2roffsu(nn->string, &su, SCALE_EN)) {
+		len = term_hspan(p, &su);
+		mt->lmargin[mt->lmargincur] = len;
+	} else
+		len = mt->lmargin[mt->lmargincur];
 
 	p->offset = mt->offset;
-	p->rmargin = mt->offset + len;
-
-	if (ival >= 0)
-		mt->lmargin[mt->lmargincur] = (size_t)ival;
+	if (len > 0 || (size_t)(-len) < mt->offset)
+		p->rmargin = mt->offset + len;
+	else
+		p->rmargin = 0;
 
 	return(1);
 }
@@ -587,9 +558,9 @@ pre_PP(DECL_ARGS)
 static int
 pre_IP(DECL_ARGS)
 {
+	struct roffsu		 su;
 	const struct man_node	*nn;
-	size_t			 len;
-	int			 savelit, ival;
+	int			 len, savelit;
 
 	switch (n->type) {
 	case MAN_BODY:
@@ -606,28 +577,22 @@ pre_IP(DECL_ARGS)
 		return(1);
 	}
 
-	len = mt->lmargin[mt->lmargincur];
-	ival = -1;
-
 	/* Calculate the offset from the optional second argument. */
-	if (NULL != (nn = n->parent->head->child))
-		if (NULL != (nn = nn->next))
-			if ((ival = a2width(p, nn->string)) >= 0)
-				len = (size_t)ival;
+	if ((nn = n->parent->head->child) != NULL &&
+	    (nn = nn->next) != NULL &&
+	    a2roffsu(nn->string, &su, SCALE_EN)) {
+		len = term_hspan(p, &su);
+		mt->lmargin[mt->lmargincur] = len;
+		if (len < 0 && (size_t)(-len) > mt->offset)
+			len = -mt->offset;
+	} else
+		len = mt->lmargin[mt->lmargincur];
 
 	switch (n->type) {
 	case MAN_HEAD:
-		/* Handle zero-width lengths. */
-		if (0 == len)
-			len = term_len(p, 1);
-
 		p->offset = mt->offset;
 		p->rmargin = mt->offset + len;
 
-		/* Set the saved left-margin. */
-		if (ival >= 0)
-			mt->lmargin[mt->lmargincur] = (size_t)ival;
-
 		savelit = MANT_LITERAL & mt->fl;
 		mt->fl &= ~MANT_LITERAL;
 
@@ -672,9 +637,9 @@ post_IP(DECL_ARGS)
 static int
 pre_TP(DECL_ARGS)
 {
+	struct roffsu		 su;
 	const struct man_node	*nn;
-	size_t			 len;
-	int			 savelit, ival;
+	int			 len, savelit;
 
 	switch (n->type) {
 	case MAN_HEAD:
@@ -691,22 +656,20 @@ pre_TP(DECL_ARGS)
 		return(1);
 	}
 
-	len = (size_t)mt->lmargin[mt->lmargincur];
-	ival = -1;
-
 	/* Calculate offset. */
 
-	if (NULL != (nn = n->parent->head->child))
-		if (nn->string && 0 == (MAN_LINE & nn->flags))
-			if ((ival = a2width(p, nn->string)) >= 0)
-				len = (size_t)ival;
+	if ((nn = n->parent->head->child) != NULL &&
+	    nn->string != NULL && ! (MAN_LINE & nn->flags) &&
+	    a2roffsu(nn->string, &su, SCALE_EN)) {
+		len = term_hspan(p, &su);
+		mt->lmargin[mt->lmargincur] = len;
+		if (len < 0 && (size_t)(-len) > mt->offset)
+			len = -mt->offset;
+	} else
+		len = mt->lmargin[mt->lmargincur];
 
 	switch (n->type) {
 	case MAN_HEAD:
-		/* Handle zero-length properly. */
-		if (0 == len)
-			len = term_len(p, 1);
-
 		p->offset = mt->offset;
 		p->rmargin = mt->offset + len;
 
@@ -725,9 +688,6 @@ pre_TP(DECL_ARGS)
 
 		if (savelit)
 			mt->fl |= MANT_LITERAL;
-		if (ival >= 0)
-			mt->lmargin[mt->lmargincur] = (size_t)ival;
-
 		return(0);
 	case MAN_BODY:
 		p->offset = mt->offset + len;
@@ -872,8 +832,8 @@ post_SH(DECL_ARGS)
 static int
 pre_RS(DECL_ARGS)
 {
-	int		 ival;
-	size_t		 sz;
+	struct roffsu	 su;
+	int		 len;
 
 	switch (n->type) {
 	case MAN_BLOCK:
@@ -885,13 +845,16 @@ pre_RS(DECL_ARGS)
 		break;
 	}
 
-	sz = term_len(p, p->defindent);
-
-	if (NULL != (n = n->parent->head->child))
-		if ((ival = a2width(p, n->string)) >= 0)
-			sz = (size_t)ival;
+	if ((n = n->parent->head->child) != NULL &&
+	    a2roffsu(n->string, &su, SCALE_EN))
+		len = term_hspan(p, &su);
+	else
+		len = term_len(p, p->defindent);
 
-	mt->offset += sz;
+	if (len > 0 || (size_t)(-len) < mt->offset)
+		mt->offset += len;
+	else
+		mt->offset = 0;
 	p->offset = mt->offset;
 	p->rmargin = p->maxrmargin;
 
@@ -905,8 +868,8 @@ pre_RS(DECL_ARGS)
 static void
 post_RS(DECL_ARGS)
 {
-	int		 ival;
-	size_t		 sz;
+	struct roffsu	 su;
+	int		 len;
 
 	switch (n->type) {
 	case MAN_BLOCK:
@@ -918,13 +881,16 @@ post_RS(DECL_ARGS)
 		break;
 	}
 
-	sz = term_len(p, p->defindent);
-
-	if (NULL != (n = n->parent->head->child))
-		if ((ival = a2width(p, n->string)) >= 0)
-			sz = (size_t)ival;
+	if ((n = n->parent->head->child) != NULL &&
+	    a2roffsu(n->string, &su, SCALE_EN))
+		len = term_hspan(p, &su);
+	else
+		len = term_len(p, p->defindent);
 
-	mt->offset = mt->offset < sz ?  0 : mt->offset - sz;
+	if (len < 0 || (size_t)len < mt->offset)
+		mt->offset -= len;
+	else
+		mt->offset = 0;
 	p->offset = mt->offset;
 
 	if (--mt->lmarginsz < MAXMARGINS)
diff --git a/mdoc_html.c b/mdoc_html.c
index 402ee1ad..885565e3 100644
--- a/mdoc_html.c
+++ b/mdoc_html.c
@@ -282,7 +282,8 @@ a2width(const char *p, struct roffsu *su)
 	if (a2roffsu(p, su, SCALE_MAX) < 2) {
 		su->unit = SCALE_EN;
 		su->scale = html_strlen(p);
-	}
+	} else if (su->scale < 0.0)
+		su->scale = 0.0;
 }
 
 /*
@@ -1566,9 +1567,12 @@ mdoc_sp_pre(MDOC_ARGS)
 	SCALE_VS_INIT(&su, 1);
 
 	if (MDOC_sp == n->tok) {
-		if (NULL != (n = n->child))
+		if (NULL != (n = n->child)) {
 			if ( ! a2roffsu(n->string, &su, SCALE_VS))
 				su.scale = 1.0;
+			else if (su.scale < 0.0)
+				su.scale = 0.0;
+		}
 	} else
 		su.scale = 0.0;
 
diff --git a/mdoc_man.c b/mdoc_man.c
index 6995f872..f6ee541d 100644
--- a/mdoc_man.c
+++ b/mdoc_man.c
@@ -435,6 +435,8 @@ print_offs(const char *v, int keywords)
 	else if (keywords && !strcmp(v, "indent-two"))
 		sz = 12;
 	else if (a2roffsu(v, &su, SCALE_EN) > 1) {
+		if (su.scale < 0.0)
+			su.scale = 0.0;
 		if (SCALE_EN == su.unit)
 			sz = su.scale;
 		else {
@@ -482,6 +484,8 @@ print_width(const char *v, const struct mdoc_node *child, size_t defsz)
 	if (NULL == v)
 		sz = defsz;
 	else if (a2roffsu(v, &su, SCALE_MAX) > 1) {
+		if (su.scale < 0.0)
+			su.scale = 0.0;
 		if (SCALE_EN == su.unit)
 			sz = su.scale;
 		else {
diff --git a/mdoc_term.c b/mdoc_term.c
index 4a8ddb86..d8004b9a 100644
--- a/mdoc_term.c
+++ b/mdoc_term.c
@@ -533,7 +533,8 @@ a2width(const struct termp *p, const char *v)
 	if (a2roffsu(v, &su, SCALE_MAX) < 2) {
 		SCALE_HS_INIT(&su, term_strlen(p, v));
 		su.scale /= term_strlen(p, "0");
-	}
+	} else if (su.scale < 0.0)
+		su.scale = 0.0;
 
 	return(term_hspan(p, &su));
 }
diff --git a/out.c b/out.c
index f5d36fb1..b0024d3f 100644
--- a/out.c
+++ b/out.c
@@ -94,9 +94,6 @@ a2roffsu(const char *src, struct roffsu *dst, enum roffscale def)
 		break;
 	}
 
-	/* FIXME: do this in the caller. */
-	if (dst->scale < 0.0)
-		dst->scale = 0.0;
 	return(*endptr == '\0' ? 2 : 1);
 }
 
diff --git a/term.c b/term.c
index 78dd69f1..ee9f31f3 100644
--- a/term.c
+++ b/term.c
@@ -101,7 +101,6 @@ term_flushln(struct termp *p)
 	size_t		 j;     /* temporary loop index for p->buf */
 	size_t		 jhy;	/* last hyph before overflow w/r/t j */
 	size_t		 maxvis; /* output position of visible boundary */
-	size_t		 rmargin; /* the rightmost of the two margins */
 
 	/*
 	 * First, establish the maximum columns of "visible" content.
@@ -114,8 +113,7 @@ term_flushln(struct termp *p)
 	 * is negative, it gets sign extended.  Subtracting that
 	 * very large size_t effectively adds a small number to dv.
 	 */
-	rmargin = p->rmargin > p->offset ? p->rmargin : p->offset;
-	dv = p->rmargin - p->offset;
+	dv = p->rmargin > p->offset ? p->rmargin - p->offset : 0;
 	maxvis = (int)dv > p->overstep ? dv - (size_t)p->overstep : 0;
 
 	if (p->flags & TERMP_NOBREAK) {
@@ -193,8 +191,9 @@ term_flushln(struct termp *p)
 			(*p->endline)(p);
 			p->viscol = 0;
 			if (TERMP_BRIND & p->flags) {
-				vbl = rmargin;
-				vend += rmargin - p->offset;
+				vbl = p->rmargin;
+				vend += p->rmargin;
+				vend -= p->offset;
 			} else
 				vbl = p->offset;
 
@@ -770,7 +769,7 @@ term_strlen(const struct termp *p, const char *cp)
 	return(sz);
 }
 
-size_t
+int
 term_vspan(const struct termp *p, const struct roffsu *su)
 {
 	double		 r;
@@ -809,19 +808,14 @@ term_vspan(const struct termp *p, const struct roffsu *su)
 		abort();
 		/* NOTREACHED */
 	}
-
-	if (r < 0.0)
-		r = 0.0;
-	return((size_t)(r + 0.4995));
+	return(r > 0.0 ? r + 0.4995 : r - 0.4995);
 }
 
-size_t
+int
 term_hspan(const struct termp *p, const struct roffsu *su)
 {
 	double		 v;
 
 	v = (*p->hspan)(p, su);
-	if (v < 0.0)
-		v = 0.0;
-	return((size_t)(v + 0.0005));
+	return(v > 0.0 ? v + 0.0005 : v - 0.0005);
 }
diff --git a/term.h b/term.h
index 40f2bcf9..f9170f0c 100644
--- a/term.h
+++ b/term.h
@@ -121,10 +121,8 @@ void		  term_begin(struct termp *, term_margin,
 void		  term_end(struct termp *);
 
 void		  term_setwidth(struct termp *, const char *);
-size_t		  term_hspan(const struct termp *,
-			const struct roffsu *);
-size_t		  term_vspan(const struct termp *,
-			const struct roffsu *);
+int		  term_hspan(const struct termp *, const struct roffsu *);
+int		  term_vspan(const struct termp *, const struct roffsu *);
 size_t		  term_strlen(const struct termp *, const char *);
 size_t		  term_len(const struct termp *, size_t);