implement so-called absolute horizontal motion: \h'|...',

used for example by zoem(1)

5 files changed, 17 insertions, 6 deletions

diff --git a/regress/roff/esc/h.in b/regress/roff/esc/h.in
index 56e4275c..8fa23e7b 100644
--- a/regress/roff/esc/h.in
+++ b/regress/roff/esc/h.in
@@ -9,6 +9,8 @@ simple: >\h'0'<
 .br
 rounding: >\h'0.16i'<
 .br
+absolute: >\h'|12n'<
+.br
 escape only: >\h'\w'\&'M'<
 .br
 escape at the end: >\h'0+\w'\&''<
diff --git a/regress/roff/esc/h.out_ascii b/regress/roff/esc/h.out_ascii
index ae378a45..ddfac195 100644
--- a/regress/roff/esc/h.out_ascii
+++ b/regress/roff/esc/h.out_ascii
@@ -6,6 +6,7 @@ NNAAMMEE
 DDEESSCCRRIIPPTTIIOONN
      simple: ><
      rounding: >  <
+     absolute: > <
      escape only: ><
      escape at the end: ><
      escape at the beginning: ><
diff --git a/regress/roff/esc/h.out_lint b/regress/roff/esc/h.out_lint
index b7facfb1..23ff9ce8 100644
--- a/regress/roff/esc/h.out_lint
+++ b/regress/roff/esc/h.out_lint
@@ -1,2 +1,2 @@
-mandoc: h.in:20:21: WARNING: invalid escape sequence: \h-
+mandoc: h.in:22:21: WARNING: invalid escape sequence: \h-
 mandoc: h.in:1:5: STYLE: Mdocdate missing: Dd May
diff --git a/roff.7 b/roff.7
index 1445b525..ab3a4b44 100644
--- a/roff.7
+++ b/roff.7
@@ -1,4 +1,4 @@
-.\"	$Id: roff.7,v 1.92 2017/06/14 22:51:25 schwarze Exp $
+.\"	$Id: roff.7,v 1.93 2017/06/14 23:24:17 schwarze Exp $
 .\"
 .\" Copyright (c) 2010, 2011, 2012 Kristaps Dzonsons <kristaps@bsd.lv>
 .\" Copyright (c) 2010,2011,2013-2015,2017 Ingo Schwarze <schwarze@openbsd.org>
@@ -1956,8 +1956,11 @@ and
 .Ss \eH\(aq Ns Oo +|- Oc Ns Ar number Ns \(aq
 Set the height of the current font; ignored by
 .Xr mandoc 1 .
-.Ss \eh\(aq Ns Ar width Ns \(aq
-Horizontal motion relative to the current position.
+.Ss \eh\(aq Ns Oo Cm \&| Oc Ns Ar width Ns \(aq
+Horizontal motion.
+If the vertical bar is given, the motion is relative to the current
+indentation.
+Otherwise, it is relative to the current position.
 The default scaling unit is
 .Cm m .
 .Ss \ek[ Ns Ar name ]
diff --git a/term.c b/term.c
index 71fd73d5..595390b6 100644
--- a/term.c
+++ b/term.c
@@ -1,4 +1,4 @@
-/*	$Id: term.c,v 1.272 2017/06/14 18:23:37 schwarze Exp $ */
+/*	$Id: term.c,v 1.273 2017/06/14 23:24:18 schwarze Exp $ */
 /*
  * Copyright (c) 2008, 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2010-2017 Ingo Schwarze <schwarze@openbsd.org>
@@ -526,9 +526,14 @@ term_word(struct termp *p, const char *word)
 				p->flags |= (TERMP_NOSPACE | TERMP_NONEWLINE);
 			continue;
 		case ESCAPE_HORIZ:
+			if (*seq == '|') {
+				seq++;
+				uc = -p->col;
+			} else
+				uc = 0;
 			if (a2roffsu(seq, &su, SCALE_EM) == NULL)
 				continue;
-			uc = term_hen(p, &su);
+			uc += term_hen(p, &su);
 			if (uc > 0)
 				while (uc-- > 0)
 					bufferc(p, ASCII_NBRSP);