libman documents require `TH' and at least one node.

libman requirements documented in man.7 STRUCTURE section.
Added STRUCTURE section to mdoc.7, too.

5 files changed, 56 insertions, 6 deletions

diff --git a/libman.h b/libman.h
index 8d3761ef..375f3dff 100644
--- a/libman.h
+++ b/libman.h
@@ -45,7 +45,9 @@ enum	merr {
 	WDATE,
 	WLNSCOPE,
 	WTSPACE,
-	WTQUOTE
+	WTQUOTE,
+	WNODATA,
+	WNOTITLE
 };
 
 __BEGIN_DECLS
diff --git a/man.7 b/man.7
index 01031d02..88401417 100644
--- a/man.7
+++ b/man.7
@@ -97,7 +97,7 @@ Characters may alternatively be escaped by a slash-asterisk,
 .Sq \e* ,
 with the same combinations as described above.  This form is deprecated.  
 .\" SECTION
-.Sh STRUCTURE
+.Sh SYNTAX
 Macros are one to three three characters in length and begin with a
 control character ,
 .Sq \&. ,
@@ -155,7 +155,20 @@ The
 .Sq \&.TP
 macro is similar, but does not need an empty argument line to trigger
 the behaviour.
-.\" PARAGRAPH
+.\" SECTION
+.Sh STRUCTURE
+Each
+.Nm
+document must contain contains at least the
+.Sq \&.TH
+macro describing the document's section and title.  It may occur
+anywhere in the document, although conventionally, it appears as the
+first macro.
+.Pp
+Beyond the 
+.Sq \&.TH ,
+at least one macro or text node must appear in the document.
+.\" SECTION
 .Sh MACROS
 This section contains a complete list of all 
 .Nm
diff --git a/man.c b/man.c
index 803c9ca4..45ce4872 100644
--- a/man.c
+++ b/man.c
@@ -466,6 +466,12 @@ man_err(struct man *m, int line, int pos,
 	case (WTQUOTE):
 		p = "unterminated quotation";
 		break;
+	case (WNODATA):
+		p = "document has no data";
+		break;
+	case (WNOTITLE):
+		p = "document has no title/section";
+		break;
 	}
 	assert(p);
 
diff --git a/man_validate.c b/man_validate.c
index 77ca142e..e9a65510 100644
--- a/man_validate.c
+++ b/man_validate.c
@@ -38,6 +38,7 @@ static	int	  check_le1(POSTARGS);
 static	int	  check_le2(POSTARGS);
 static	int	  check_le5(POSTARGS);
 static	int	  check_text(POSTARGS);
+static	int	  check_root(POSTARGS);
 
 static	v_post	  posts_le1[] = { check_le1, NULL };
 static	v_post	  posts_le2[] = { check_le2, NULL };
@@ -85,8 +86,7 @@ man_valid_post(struct man *m)
 	case (MAN_TEXT): 
 		return(check_text(m, m->last));
 	case (MAN_ROOT):
-		/* FIXME: validate that TH has been invoked! */
-		return(1);
+		return(check_root(m, m->last));
 	default:
 		break;
 	}
@@ -102,6 +102,19 @@ man_valid_post(struct man *m)
 
 
 static int
+check_root(POSTARGS) 
+{
+	
+	if (NULL == m->first->child)
+		return(man_nerr(m, n, WNODATA));
+	if (NULL == m->meta.title)
+		return(man_nerr(m, n, WNOTITLE));
+
+	return(1);
+}
+
+
+static int
 check_text(POSTARGS) 
 {
 	const char	*p;
diff --git a/mdoc.7 b/mdoc.7
index 52585e69..f27b31bc 100644
--- a/mdoc.7
+++ b/mdoc.7
@@ -278,7 +278,23 @@ In-lines have \(>=0 scoped arguments.
 
 \&.Yy \(lB\-arg \(lBval...\(rB\(rB arg0 arg1 argN
 .Ed
-.\"
+.\" SECTION
+.Sh STRUCTURE
+Each
+.Nm
+document must begin with the document prologue, containing, in order, 
+.Sq \&.Dd ,
+.Sq \&.Dt ,
+and
+.Sq \&.Os .
+.Pp
+Following these, the document body must begin with the NAME section
+containing at least one 
+.Sq \&.Nm
+followed by a
+.Sq \&.Nd
+macro.
+.\" SECTION
 .Sh MACROS
 This section contains a complete list of all 
 .Nm