Support for badly nested blocks, written around the time of

the Rostock mandoc hackathon and tested and polished since,
supporting constructs like:

.Ao Bo    Ac    Bc        (exp breaking exp)
.Aq Bo    eol   Bc        (imp breaking exp)
.Ao Bq    Ac    eol       (exp breaking imp)
.Ao Bo So Bc    Ac  Sc    (double break, inner before outer)
.Ao Bo So Ac    Bc  Sc    (double break, outer before inner)
.Ao Bo    Ac So Bc  Sc    (broken breaker)
.Ao Bo So Bc Do Ac  Sc Dc (broken double breaker)

There are still two known issues which are tricky:

1) Breaking two identical explicit blocks (Ao Bo Bo Ac or Aq Bo Bo eol)
fails outright, triggering a bogus syntax error.
2) Breaking a block by two identical explicit blocks (Ao Ao Bo Ac Ac Bc
or Ao Ao Bq Ac Ac eol) still has a minor rendering error left:
"<ao1 <ao2 [bo ac2> ac1> bc]>" should not have the final ">".

We can fix these later in the tree, let's not grow this diff too large.

"get it in" kristaps@

1 files changed, 18 insertions, 0 deletions

diff --git a/mdoc.c b/mdoc.c
index 59c54b83..5fc9ed95 100644
--- a/mdoc.c
+++ b/mdoc.c
@@ -332,6 +332,8 @@ node_append(struct mdoc *mdoc, struct mdoc_node *p)
 		p->parent->tail = p;
 		break;
 	case (MDOC_BODY):
+		if (p->end)
+			break;
 		assert(MDOC_BLOCK == p->parent->type);
 		p->parent->body = p;
 		break;
@@ -436,6 +438,22 @@ mdoc_body_alloc(struct mdoc *m, int line, int pos, enum mdoct tok)
 
 
 int
+mdoc_endbody_alloc(struct mdoc *m, int line, int pos, enum mdoct tok,
+		struct mdoc_node *body, enum mdoc_endbody end)
+{
+	struct mdoc_node *p;
+
+	p = node_alloc(m, line, pos, tok, MDOC_BODY);
+	p->pending = body;
+	p->end = end;
+	if ( ! node_append(m, p))
+		return(0);
+	m->next = MDOC_NEXT_SIBLING;
+	return(1);
+}
+
+
+int
 mdoc_block_alloc(struct mdoc *m, int line, int pos, 
 		enum mdoct tok, struct mdoc_arg *args)
 {