Some improvements to error handling from kristaps@:

* Make out-of-context .fi invocations not cause an error, but just a warning.
* Downgrade -man message about ignored empty paragraph to MANDOC_IGNPAR.
* Avoid syntax tree corruption when removing empty block macros.
Triggered by some reports from brad@.

5 files changed, 48 insertions, 42 deletions

diff --git a/usr.bin/mandoc/main.c b/usr.bin/mandoc/main.c
index 5165557e587..1d5d405501f 100644
--- a/usr.bin/mandoc/main.c
+++ b/usr.bin/mandoc/main.c
@@ -1,4 +1,4 @@
-/*	$Id: main.c,v 1.67 2011/01/16 01:11:50 schwarze Exp $ */
+/*	$Id: main.c,v 1.68 2011/01/16 19:27:25 schwarze Exp $ */
 /*
  * Copyright (c) 2008, 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2010 Ingo Schwarze <schwarze@openbsd.org>
@@ -143,6 +143,7 @@ static	const char * const	mandocerrs[MANDOCERR_MAX] = {
 	"list type must come first",
 	"tag lists require a width argument",
 	"missing font type",
+	"skipping end of block that is not open",
 
 	/* related to bad macro arguments */
 	"skipping argument",
diff --git a/usr.bin/mandoc/man_macro.c b/usr.bin/mandoc/man_macro.c
index a30b585b91a..413cbbd56ee 100644
--- a/usr.bin/mandoc/man_macro.c
+++ b/usr.bin/mandoc/man_macro.c
@@ -1,4 +1,4 @@
-/*	$Id: man_macro.c,v 1.26 2011/01/04 22:28:17 schwarze Exp $ */
+/*	$Id: man_macro.c,v 1.27 2011/01/16 19:27:25 schwarze Exp $ */
 /*
  * Copyright (c) 2008, 2009, 2010 Kristaps Dzonsons <kristaps@bsd.lv>
  *
@@ -103,19 +103,27 @@ rew_warn(struct man *m, struct man_node *n, enum mandocerr er)
  * will be used if an explicit block scope is being closed out.
  */
 int
-man_unscope(struct man *m, const struct man_node *n, 
+man_unscope(struct man *m, const struct man_node *to, 
 		enum mandocerr er)
 {
+	struct man_node	*n;
 
-	assert(n);
+	assert(to);
 
 	/* LINTED */
-	while (m->last != n) {
+	while (m->last != to) {
+		/*
+		 * Save the parent here, because we may delete the
+		 * m->last node in the post-validation phase and reset
+		 * it to m->last->parent, causing a step in the closing
+		 * out to be lost.
+		 */
+		n = m->last->parent;
 		if ( ! rew_warn(m, m->last, er))
 			return(0);
 		if ( ! man_valid_post(m))
 			return(0);
-		m->last = m->last->parent;
+		m->last = n;
 		assert(m->last);
 	}
 
diff --git a/usr.bin/mandoc/man_validate.c b/usr.bin/mandoc/man_validate.c
index 6da4350a1f0..77db6986725 100644
--- a/usr.bin/mandoc/man_validate.c
+++ b/usr.bin/mandoc/man_validate.c
@@ -1,4 +1,4 @@
-/*	$Id: man_validate.c,v 1.38 2011/01/04 22:28:17 schwarze Exp $ */
+/*	$Id: man_validate.c,v 1.39 2011/01/16 19:27:25 schwarze Exp $ */
 /*
  * Copyright (c) 2008, 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2010 Ingo Schwarze <schwarze@openbsd.org>
@@ -77,12 +77,12 @@ static	const struct man_valid man_valids[MAN_MAX] = {
 	{ pres_bline, posts_th }, /* TH */
 	{ pres_bline, posts_sec }, /* SH */
 	{ pres_bline, posts_sec }, /* SS */
-	{ pres_bline, posts_par }, /* TP */
+	{ pres_bline, NULL }, /* TP */
 	{ pres_bline, posts_par }, /* LP */
 	{ pres_bline, posts_par }, /* PP */
 	{ pres_bline, posts_par }, /* P */
-	{ pres_bline, posts_par }, /* IP */
-	{ pres_bline, posts_par }, /* HP */
+	{ pres_bline, NULL }, /* IP */
+	{ pres_bline, NULL }, /* HP */
 	{ NULL, NULL }, /* SM */
 	{ NULL, NULL }, /* SB */
 	{ NULL, NULL }, /* BI */
@@ -356,33 +356,22 @@ static int
 check_par(CHKARGS)
 {
 
-	if (MAN_BODY == n->type) 
-		switch (n->tok) {
-		case (MAN_IP):
-			/* FALLTHROUGH */
-		case (MAN_HP):
-			/* FALLTHROUGH */
-		case (MAN_TP):
-			/* Body-less lists are ok. */
-			break;
-		default:
-			if (0 == n->nchild)
-				man_nmsg(m, n, MANDOCERR_NOBODY);
-			break;
-		}
-	if (MAN_HEAD == n->type)
-		switch (n->tok) {
-		case (MAN_PP):
-			/* FALLTHROUGH */
-		case (MAN_P):
-			/* FALLTHROUGH */
-		case (MAN_LP):
-			if (n->nchild)
-				man_nmsg(m, n, MANDOCERR_ARGSLOST);
-			break;
-		default:
-			break;
-		}
+	switch (n->type) {
+	case (MAN_BLOCK):
+		if (0 == n->body->nchild)
+			man_node_delete(m, n);
+		break;
+	case (MAN_BODY):
+		if (0 == n->nchild)
+			man_nmsg(m, n, MANDOCERR_IGNPAR);
+		break;
+	case (MAN_HEAD):
+		if (n->nchild)
+			man_nmsg(m, n, MANDOCERR_ARGSLOST);
+		break;
+	default:
+		break;
+	}
 
 	return(1);
 }
@@ -486,7 +475,7 @@ post_fi(CHKARGS)
 {
 
 	if ( ! (MAN_LITERAL & m->flags))
-		man_nmsg(m, n, MANDOCERR_NOSCOPE);
+		man_nmsg(m, n, MANDOCERR_WNOSCOPE);
 
 	m->flags &= ~MAN_LITERAL;
 	return(1);
diff --git a/usr.bin/mandoc/mandoc.h b/usr.bin/mandoc/mandoc.h
index 55dc636cbc5..923b3f774a7 100644
--- a/usr.bin/mandoc/mandoc.h
+++ b/usr.bin/mandoc/mandoc.h
@@ -1,4 +1,4 @@
-/*	$Id: mandoc.h,v 1.30 2011/01/16 01:11:50 schwarze Exp $ */
+/*	$Id: mandoc.h,v 1.31 2011/01/16 19:27:25 schwarze Exp $ */
 /*
  * Copyright (c) 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
  *
@@ -80,6 +80,7 @@ enum	mandocerr {
 	MANDOCERR_LISTFIRST, /* list type must come first */
 	MANDOCERR_NOWIDTHARG, /* tag lists require a width argument */
 	MANDOCERR_FONTTYPE, /* missing font type */
+	MANDOCERR_WNOSCOPE, /* skipping end of block that is not open */
 
 	/* related to bad macro arguments */
 	MANDOCERR_IGNARGV, /* skipping argument */
diff --git a/usr.bin/mandoc/mdoc_macro.c b/usr.bin/mandoc/mdoc_macro.c
index 699ebbb92f6..a638ed9445c 100644
--- a/usr.bin/mandoc/mdoc_macro.c
+++ b/usr.bin/mandoc/mdoc_macro.c
@@ -1,4 +1,4 @@
-/*	$Id: mdoc_macro.c,v 1.62 2011/01/04 22:28:17 schwarze Exp $ */
+/*	$Id: mdoc_macro.c,v 1.63 2011/01/16 19:27:25 schwarze Exp $ */
 /*
  * Copyright (c) 2008, 2009, 2010 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2010 Ingo Schwarze <schwarze@openbsd.org>
@@ -248,17 +248,24 @@ lookup_raw(const char *p)
 static int
 rew_last(struct mdoc *mdoc, const struct mdoc_node *to)
 {
-	struct mdoc_node *n;
+	struct mdoc_node *n, *np;
 
 	assert(to);
 	mdoc->next = MDOC_NEXT_SIBLING;
 
 	/* LINTED */
 	while (mdoc->last != to) {
+		/*
+		 * Save the parent here, because we may delete the
+		 * m->last node in the post-validation phase and reset
+		 * it to m->last->parent, causing a step in the closing
+		 * out to be lost.
+		 */
+		np = mdoc->last->parent;
 		if ( ! mdoc_valid_post(mdoc))
 			return(0);
 		n = mdoc->last;
-		mdoc->last = mdoc->last->parent;
+		mdoc->last = np;
 		assert(mdoc->last);
 		mdoc->last->last = n;
 	}