support the highly surprising escape sequence \# (line continuation

with comment); used for example by gropdf(1)

diff --git a/share/man/man7/roff.7 b/share/man/man7/roff.7
index 6a7849e..b2edb41 100644 (file)
--- a/share/man/man7/roff.7
+++ b/share/man/man7/roff.7
@@ -1,4 +1,4 @@
-.\"    $OpenBSD: roff.7,v 1.79 2018/08/16 14:01:35 schwarze Exp $
+.\"    $OpenBSD: roff.7,v 1.80 2018/08/18 21:36:53 schwarze Exp $
 .\"
 .\" Copyright (c) 2010, 2011, 2012 Kristaps Dzonsons <kristaps@bsd.lv>
 .\" Copyright (c) 2010-2018 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: August 16 2018 $
+.Dd $Mdocdate: August 18 2018 $
 .Dt ROFF 7
 .Os
 .Sh NAME
@@ -1817,6 +1817,12 @@ is an unpaddable space-sized non-breaking space character; see
 .Ss \e\(dq
 The rest of the input line is treated as
 .Sx Comments .
+.Ss \e#
+Line continuation with comment.
+Discard the rest of the physical input line and continue the logical
+input line on the next physical input line, joining the text on
+both lines together as if it were on a single input line.
+This is a groff extension.
 .Ss \e%
 Hyphenation allowed at this point of the word; ignored by
 .Xr mandoc 1 .

diff --git a/usr.bin/mandoc/roff.c b/usr.bin/mandoc/roff.c
index 364c6b1..1e8b65e 100644 (file)
--- a/usr.bin/mandoc/roff.c
+++ b/usr.bin/mandoc/roff.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: roff.c,v 1.205 2018/08/18 02:03:41 schwarze Exp $ */
+/*     $OpenBSD: roff.c,v 1.206 2018/08/18 21:36:53 schwarze Exp $ */
 /*
  * Copyright (c) 2008-2012, 2014 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2010-2015, 2017, 2018 Ingo Schwarze <schwarze@openbsd.org>
@@ -1203,7 +1203,14 @@ roff_res(struct roff *r, struct buf *buf, int ln, int pos)
                        r->man->next = ROFF_NEXT_SIBLING;
                }
 
-               /* Discard comments. */
+               /* Line continuation with comment. */
+
+               if (stesc[1] == '#') {
+                       *stesc = '\0';
+                       return ROFF_APPEND;
+               }
+
+               /* Discard normal comments. */
 
                while (stesc > start && stesc[-1] == ' ')
                        stesc--;