Rudimentary implementation of the e, x, and z table layout modifiers

to equalize, maximize, and ignore the width of columns.
Does not yet take vertical rulers into account,
and does not do line breaks within table cells.
Considerably improves the lftp(1) manual; issue noticed by sthen@.

7 files changed, 99 insertions, 19 deletions

diff --git a/mandoc.h b/mandoc.h
index 9762f8eb..e7eefc07 100644
--- a/mandoc.h
+++ b/mandoc.h
@@ -1,4 +1,4 @@
-/*	$Id: mandoc.h,v 1.162 2014/10/12 19:31:41 schwarze Exp $ */
+/*	$Id: mandoc.h,v 1.163 2014/10/14 02:16:06 schwarze Exp $ */
 /*
  * Copyright (c) 2010, 2011, 2014 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2010-2014 Ingo Schwarze <schwarze@openbsd.org>
@@ -246,6 +246,7 @@ struct	tbl_cell {
 #define	TBL_CELL_EQUAL	 (1 << 4) /* e, E */
 #define	TBL_CELL_UP	 (1 << 5) /* u, U */
 #define	TBL_CELL_WIGN	 (1 << 6) /* z, Z */
+#define	TBL_CELL_WMAX	 (1 << 7) /* x, X */
 	struct tbl_head	 *head;
 };
 
diff --git a/out.c b/out.c
index 783a04c5..93cc9658 100644
--- a/out.c
+++ b/out.c
@@ -1,7 +1,7 @@
-/*	$Id: out.c,v 1.51 2014/08/12 19:28:16 schwarze Exp $ */
+/*	$Id: out.c,v 1.52 2014/10/14 02:16:06 schwarze Exp $ */
 /*
  * Copyright (c) 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
- * Copyright (c) 2011 Ingo Schwarze <schwarze@openbsd.org>
+ * Copyright (c) 2011, 2014 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
@@ -139,11 +139,14 @@ a2roffsu(const char *src, struct roffsu *dst, enum roffscale def)
  * used for the actual width calculations.
  */
 void
-tblcalc(struct rofftbl *tbl, const struct tbl_span *sp)
+tblcalc(struct rofftbl *tbl, const struct tbl_span *sp,
+	size_t totalwidth)
 {
 	const struct tbl_dat	*dp;
 	struct roffcol		*col;
+	size_t			 ewidth, xwidth;
 	int			 spans;
+	int			 icol, maxcol, necol, nxcol;
 
 	/*
 	 * Allocate the master column specifiers.  These will hold the
@@ -155,7 +158,7 @@ tblcalc(struct rofftbl *tbl, const struct tbl_span *sp)
 	tbl->cols = mandoc_calloc((size_t)sp->opts->cols,
 	    sizeof(struct roffcol));
 
-	for ( ; sp; sp = sp->next) {
+	for (maxcol = 0; sp; sp = sp->next) {
 		if (TBL_SPAN_DATA != sp->pos)
 			continue;
 		spans = 1;
@@ -170,11 +173,72 @@ tblcalc(struct rofftbl *tbl, const struct tbl_span *sp)
 			spans = dp->spans;
 			if (1 < spans)
 				continue;
-			assert(dp->layout);
-			col = &tbl->cols[dp->layout->head->ident];
+			icol = dp->layout->head->ident;
+			if (maxcol < icol)
+				maxcol = icol;
+			col = tbl->cols + icol;
+			col->flags |= dp->layout->flags;
+			if (dp->layout->flags & TBL_CELL_WIGN)
+				continue;
 			tblcalc_data(tbl, col, sp->opts, dp);
 		}
 	}
+
+	/*
+	 * Count columns to equalize and columns to maximize.
+	 * Find maximum width of the columns to equalize.
+	 * Find total width of the columns *not* to maximize.
+	 */
+
+	necol = nxcol = 0;
+	ewidth = xwidth = 0;
+	for (icol = 0; icol <= maxcol; icol++) {
+		col = tbl->cols + icol;
+		if (col->flags & TBL_CELL_EQUAL) {
+			necol++;
+			if (ewidth < col->width)
+				ewidth = col->width;
+		}
+		if (col->flags & TBL_CELL_WMAX)
+			nxcol++;
+		else
+			xwidth += col->width;
+	}
+
+	/*
+	 * Equalize columns, if requested for any of them.
+	 * Update total width of the columns not to maximize.
+	 */
+
+	if (necol) {
+		for (icol = 0; icol <= maxcol; icol++) {
+			col = tbl->cols + icol;
+			if ( ! (col->flags & TBL_CELL_EQUAL))
+				continue;
+			if (col->width == ewidth)
+				continue;
+			if (nxcol && totalwidth)
+				xwidth += ewidth - col->width;
+			col->width = ewidth;
+		}
+	}
+
+	/*
+	 * If there are any columns to maximize, find the total
+	 * available width, deducting 3n margins between columns.
+	 * Distribute the available width evenly.
+	 */
+
+	if (nxcol && totalwidth) {
+		xwidth = totalwidth - 3*maxcol - xwidth;
+		for (icol = 0; icol <= maxcol; icol++) {
+			col = tbl->cols + icol;
+			if ( ! (col->flags & TBL_CELL_WMAX))
+				continue;
+			col->width = xwidth / nxcol--;
+			xwidth -= col->width;
+		}
+	}
 }
 
 static void
diff --git a/out.h b/out.h
index a1133ede..de38ec17 100644
--- a/out.h
+++ b/out.h
@@ -1,4 +1,4 @@
-/*	$Id: out.h,v 1.23 2014/08/12 19:28:03 schwarze Exp $ */
+/*	$Id: out.h,v 1.24 2014/10/14 02:16:06 schwarze Exp $ */
 /*
  * Copyright (c) 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
  *
@@ -34,6 +34,7 @@ enum	roffscale {
 struct	roffcol {
 	size_t		 width; /* width of cell */
 	size_t		 decimal; /* decimal position in cell */
+	int		 flags; /* layout flags, see tbl_cell */
 };
 
 struct	roffsu {
@@ -64,7 +65,8 @@ __BEGIN_DECLS
 	while (/* CONSTCOND */ 0)
 
 int		  a2roffsu(const char *, struct roffsu *, enum roffscale);
-void		  tblcalc(struct rofftbl *tbl, const struct tbl_span *);
+void		  tblcalc(struct rofftbl *tbl,
+			const struct tbl_span *, size_t);
 
 __END_DECLS
 
diff --git a/tbl.7 b/tbl.7
index 49ccecde..4073290c 100644
--- a/tbl.7
+++ b/tbl.7
@@ -1,4 +1,4 @@
-.\"	$Id: tbl.7,v 1.19 2014/10/13 23:31:46 schwarze Exp $
+.\"	$Id: tbl.7,v 1.20 2014/10/14 02:16:06 schwarze Exp $
 .\"
 .\" Copyright (c) 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
 .\" Copyright (c) 2014 Ingo Schwarze <schwarze@openbsd.org>
@@ -15,7 +15,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: October 13 2014 $
+.Dd $Mdocdate: October 14 2014 $
 .Dt TBL 7
 .Os
 .Sh NAME
@@ -248,6 +248,11 @@ The following case-insensitive modifier keys are available:
 .Bl -tag -width 2n
 .It Cm b
 Use a bold font for the contents of this column.
+.It Cm e
+Make this column wider to match the maximum width
+of any other column also having the
+.Cm e
+modifier.
 .It Cm f
 The next character selects the font to use for this column.
 See the
@@ -255,16 +260,21 @@ See the
 manual for supported one-character font names.
 .It Cm i
 Use an italic font for the contents of this column.
+.It Cm x
+After determining the width of all other columns, distribute the
+rest of the line length among all columns having the
+.Cm x
+modifier.
+.It Cm z
+Do not use this cell for determining the width of this column.
 .El
 .Pp
 The modifiers
 .Cm d ,
-.Cm e ,
-.Cm r ,
 .Cm t ,
 .Cm u ,
 and
-.Cm z
+.Cm w
 are ignored by
 .Xr mandoc 1 .
 .Pp
diff --git a/tbl_html.c b/tbl_html.c
index 2a93de63..1de1bb8b 100644
--- a/tbl_html.c
+++ b/tbl_html.c
@@ -1,4 +1,4 @@
-/*	$Id: tbl_html.c,v 1.12 2014/08/10 23:54:41 schwarze Exp $ */
+/*	$Id: tbl_html.c,v 1.13 2014/10/14 02:16:06 schwarze Exp $ */
 /*
  * Copyright (c) 2011 Kristaps Dzonsons <kristaps@bsd.lv>
  *
@@ -57,7 +57,7 @@ html_tblopen(struct html *h, const struct tbl_span *sp)
 	if (TBL_SPAN_FIRST & sp->flags) {
 		h->tbl.len = html_tbl_len;
 		h->tbl.slen = html_tbl_strlen;
-		tblcalc(&h->tbl, sp);
+		tblcalc(&h->tbl, sp, 0);
 	}
 
 	assert(NULL == h->tblt);
diff --git a/tbl_layout.c b/tbl_layout.c
index 3d27ee1a..71078a9d 100644
--- a/tbl_layout.c
+++ b/tbl_layout.c
@@ -1,4 +1,4 @@
-/*	$Id: tbl_layout.c,v 1.28 2014/10/07 14:07:03 schwarze Exp $ */
+/*	$Id: tbl_layout.c,v 1.29 2014/10/14 02:16:06 schwarze Exp $ */
 /*
  * Copyright (c) 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2012, 2014 Ingo Schwarze <schwarze@openbsd.org>
@@ -168,6 +168,9 @@ mod:
 		goto mod;
 	case 'w':  /* XXX for now, ignore minimal column width */
 		goto mod;
+	case 'x':
+		cp->flags |= TBL_CELL_WMAX;
+		goto mod;
 	case 'f':
 		break;
 	case 'r':
diff --git a/tbl_term.c b/tbl_term.c
index 32fd1a78..6a733506 100644
--- a/tbl_term.c
+++ b/tbl_term.c
@@ -1,4 +1,4 @@
-/*	$Id: tbl_term.c,v 1.29 2014/10/13 23:31:46 schwarze Exp $ */
+/*	$Id: tbl_term.c,v 1.30 2014/10/14 02:16:06 schwarze Exp $ */
 /*
  * Copyright (c) 2009, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2011, 2012, 2014 Ingo Schwarze <schwarze@openbsd.org>
@@ -91,7 +91,7 @@ term_tbl(struct termp *tp, const struct tbl_span *sp)
 		tp->tbl.slen = term_tbl_strlen;
 		tp->tbl.arg = tp;
 
-		tblcalc(&tp->tbl, sp);
+		tblcalc(&tp->tbl, sp, rmargin - tp->offset);
 	}
 
 	/* Horizontal frame at the start of boxed tables. */