If a .Bd block has no arguments at all, drop the block and only keep

its contents.  Removing a gratuitious difference to groff output
found after a related bug report from krw@.

8 files changed, 37 insertions, 10 deletions

diff --git a/regress/usr.bin/mandoc/mdoc/Bd/badargs.in b/regress/usr.bin/mandoc/mdoc/Bd/badargs.in
index 4b06a528776..0d8b3f4d647 100644
--- a/regress/usr.bin/mandoc/mdoc/Bd/badargs.in
+++ b/regress/usr.bin/mandoc/mdoc/Bd/badargs.in
@@ -1,4 +1,4 @@
-.Dd July 5, 2014
+.Dd October 27, 2015
 .Dt BD-BADARGS 1
 .Os OpenBSD
 .Sh NAME
@@ -44,3 +44,8 @@ missing -file argument:
 ragged
 offset indent
 .Ed
+no argument whatsoever:
+.Bd
+no
+argument
+.Ed
diff --git a/regress/usr.bin/mandoc/mdoc/Bd/badargs.out_ascii b/regress/usr.bin/mandoc/mdoc/Bd/badargs.out_ascii
index 8cfd38e5f58..1a123a6cafa 100644
--- a/regress/usr.bin/mandoc/mdoc/Bd/badargs.out_ascii
+++ b/regress/usr.bin/mandoc/mdoc/Bd/badargs.out_ascii
@@ -25,5 +25,6 @@ DDEESSCCRRIIPPTTIIOONN
      missing -file argument:
 
            ragged offset indent
+     no argument whatsoever: no argument
 
-OpenBSD                          July 5, 2014                          OpenBSD
+OpenBSD                        October 27, 2015                        OpenBSD
diff --git a/regress/usr.bin/mandoc/mdoc/Bd/badargs.out_lint b/regress/usr.bin/mandoc/mdoc/Bd/badargs.out_lint
index 554577d4062..10c9cb021dd 100644
--- a/regress/usr.bin/mandoc/mdoc/Bd/badargs.out_lint
+++ b/regress/usr.bin/mandoc/mdoc/Bd/badargs.out_lint
@@ -1,11 +1,12 @@
-mandoc: badargs.in:9:13: WARNING: empty argument, using 0n: Bd -offset
 mandoc: badargs.in:12:2: ERROR: skipping all arguments: Ed tail argument
+mandoc: badargs.in:19:16: ERROR: skipping excess arguments: Bd ... -bogus
+mandoc: badargs.in:9:13: WARNING: empty argument, using 0n: Bd -offset
 mandoc: badargs.in:14:34: WARNING: duplicate argument: Bd -compact
 mandoc: badargs.in:14:43: WARNING: duplicate argument: Bd -offset 6n
 mandoc: badargs.in:19:2: WARNING: missing display type, using -ragged: Bd
-mandoc: badargs.in:19:16: ERROR: skipping excess arguments: Bd ... -bogus
 mandoc: badargs.in:24:2: WARNING: skipping duplicate display type: Bd -unfilled
 mandoc: badargs.in:28:2: WARNING: skipping duplicate display type: Bd -ragged
 mandoc: badargs.in:33:2: ERROR: NOT IMPLEMENTED: Bd -file
 mandoc: badargs.in:38:2: ERROR: NOT IMPLEMENTED: Bd -file
 mandoc: badargs.in:43:2: ERROR: NOT IMPLEMENTED: Bd -file
+mandoc: badargs.in:48:2: ERROR: skipping display without arguments: Bd
diff --git a/usr.bin/mandoc/mandoc.1 b/usr.bin/mandoc/mandoc.1
index 39a66a81283..3500983b2e4 100644
--- a/usr.bin/mandoc/mandoc.1
+++ b/usr.bin/mandoc/mandoc.1
@@ -1,4 +1,4 @@
-.\"	$OpenBSD: mandoc.1,v 1.86 2015/09/26 17:12:45 jmc Exp $
+.\"	$OpenBSD: mandoc.1,v 1.87 2015/10/30 19:03:36 schwarze Exp $
 .\"
 .\" Copyright (c) 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
 .\" Copyright (c) 2012, 2014, 2015 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: September 26 2015 $
+.Dd $Mdocdate: October 30 2015 $
 .Dt MANDOC 1
 .Os
 .Sh NAME
@@ -1600,6 +1600,13 @@ By requesting the inclusion of a sensitive file, a malicious document
 might otherwise trick a privileged user into inadvertently displaying
 the file on the screen, revealing the file content to bystanders.
 The argument is ignored including the file name following it.
+.It Sy "skipping display without arguments"
+.Pq mdoc
+A
+.Ic \&Bd
+block macro does not have any arguments.
+The block is discarded, and the block content is displayed in
+whatever mode was active before the block.
 .It Sy "missing list type, using -item"
 .Pq mdoc
 A
diff --git a/usr.bin/mandoc/mandoc.h b/usr.bin/mandoc/mandoc.h
index 25490fd8ebd..0aecdb0ce4d 100644
--- a/usr.bin/mandoc/mandoc.h
+++ b/usr.bin/mandoc/mandoc.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mandoc.h,v 1.148 2015/10/13 22:57:49 schwarze Exp $ */
+/*	$OpenBSD: mandoc.h,v 1.149 2015/10/30 19:03:36 schwarze Exp $ */
 /*
  * Copyright (c) 2010, 2011, 2014 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2010-2015 Ingo Schwarze <schwarze@openbsd.org>
@@ -172,6 +172,7 @@ enum	mandocerr {
 	/* related to request and macro arguments */
 	MANDOCERR_NAMESC, /* escaped character not allowed in a name: name */
 	MANDOCERR_BD_FILE, /* NOT IMPLEMENTED: Bd -file */
+	MANDOCERR_BD_NOARG, /* skipping display without arguments: Bd */
 	MANDOCERR_BL_NOTYPE, /* missing list type, using -item: Bl */
 	MANDOCERR_NM_NONAME, /* missing manual name, using "": Nm */
 	MANDOCERR_OS_UNAME, /* uname(3) system call failed, using UNKNOWN */
diff --git a/usr.bin/mandoc/mdoc.c b/usr.bin/mandoc/mdoc.c
index 0a84263dcb5..56ae0c9acd5 100644
--- a/usr.bin/mandoc/mdoc.c
+++ b/usr.bin/mandoc/mdoc.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mdoc.c,v 1.144 2015/10/20 02:00:49 schwarze Exp $ */
+/*	$OpenBSD: mdoc.c,v 1.145 2015/10/30 19:03:36 schwarze Exp $ */
 /*
  * Copyright (c) 2008, 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2010, 2012-2015 Ingo Schwarze <schwarze@openbsd.org>
@@ -203,6 +203,7 @@ mdoc_node_relink(struct roff_man *mdoc, struct roff_node *p)
 {
 
 	roff_node_unlink(mdoc, p);
+	p->prev = p->next = NULL;
 	roff_node_append(mdoc, p);
 }
 
diff --git a/usr.bin/mandoc/mdoc_validate.c b/usr.bin/mandoc/mdoc_validate.c
index b5f8fcebdb0..5c65594b432 100644
--- a/usr.bin/mandoc/mdoc_validate.c
+++ b/usr.bin/mandoc/mdoc_validate.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mdoc_validate.c,v 1.215 2015/10/21 23:49:05 schwarze Exp $ */
+/*	$OpenBSD: mdoc_validate.c,v 1.216 2015/10/30 19:03:36 schwarze Exp $ */
 /*
  * Copyright (c) 2008-2012 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2010-2015 Ingo Schwarze <schwarze@openbsd.org>
@@ -886,6 +886,16 @@ post_display(POST_ARGS)
 		break;
 	case ROFFT_BLOCK:
 		if (n->tok == MDOC_Bd) {
+			if (n->args == NULL) {
+				mandoc_msg(MANDOCERR_BD_NOARG,
+				    mdoc->parse, n->line, n->pos, "Bd");
+				mdoc->next = ROFF_NEXT_SIBLING;
+				while (n->body->child != NULL)
+					mdoc_node_relink(mdoc,
+					    n->body->child);
+				roff_node_delete(mdoc, n);
+				break;
+			}
 			post_bd(mdoc);
 			post_prevpar(mdoc);
 		}
diff --git a/usr.bin/mandoc/read.c b/usr.bin/mandoc/read.c
index 830c73ef2c6..c5c7da6f65b 100644
--- a/usr.bin/mandoc/read.c
+++ b/usr.bin/mandoc/read.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: read.c,v 1.119 2015/10/13 22:57:49 schwarze Exp $ */
+/*	$OpenBSD: read.c,v 1.120 2015/10/30 19:03:36 schwarze Exp $ */
 /*
  * Copyright (c) 2008, 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2010-2015 Ingo Schwarze <schwarze@openbsd.org>
@@ -210,6 +210,7 @@ static	const char * const	mandocerrs[MANDOCERR_MAX] = {
 	/* related to request and macro arguments */
 	"escaped character not allowed in a name",
 	"NOT IMPLEMENTED: Bd -file",
+	"skipping display without arguments",
 	"missing list type, using -item",
 	"missing manual name, using \"\"",
 	"uname(3) system call failed, using UNKNOWN",