===================================================================
RCS file: /cvs/mandoc/eqn.c,v
retrieving revision 1.14
retrieving revision 1.16
diff -u -p -r1.14 -r1.16
--- mandoc/eqn.c	2011/07/21 11:57:56	1.14
+++ mandoc/eqn.c	2011/07/21 13:18:24	1.16
@@ -1,4 +1,4 @@
-/*	$Id: eqn.c,v 1.14 2011/07/21 11:57:56 kristaps Exp $ */
+/*	$Id: eqn.c,v 1.16 2011/07/21 13:18:24 kristaps Exp $ */
 /*
  * Copyright (c) 2011 Kristaps Dzonsons <kristaps@bsd.lv>
  *
@@ -37,6 +37,11 @@ struct	eqnpart {
 	int		(*fp)(struct eqn_node *);
 };
 
+struct	eqnmark {
+	const char	*name;
+	size_t		 sz;
+};
+
 enum	eqnpartt {
 	EQN_DEFINE = 0,
 	EQN_SET,
@@ -54,7 +59,8 @@ static	const char	*eqn_nexttok(struct eqn_node *, size
 static	const char	*eqn_nextrawtok(struct eqn_node *, size_t *);
 static	const char	*eqn_next(struct eqn_node *, 
 				char, size_t *, int);
-static	int		 eqn_box(struct eqn_node *, struct eqn_box *);
+static	int		 eqn_box(struct eqn_node *, 
+				struct eqn_box *, struct eqn_box **);
 
 static	const struct eqnpart eqnparts[EQN__MAX] = {
 	{ "define", 6, eqn_do_define }, /* EQN_DEFINE */
@@ -62,6 +68,18 @@ static	const struct eqnpart eqnparts[EQN__MAX] = {
 	{ "undef", 5, eqn_do_undef }, /* EQN_UNDEF */
 };
 
+static	const struct eqnmark eqnmarks[EQNMARK__MAX] = {
+	{ "", 0 }, /* EQNMARK_NONE */
+	{ "dot", 3 }, /* EQNMARK_DOT */
+	{ "dotdot", 6 }, /* EQNMARK_DOTDOT */
+	{ "hat", 3 }, /* EQNMARK_HAT */
+	{ "tilde", 5 }, /* EQNMARK_TILDE */
+	{ "vec", 3 }, /* EQNMARK_VEC */
+	{ "dyad", 4 }, /* EQNMARK_DYAD */
+	{ "bar", 3 }, /* EQNMARK_BAR */
+	{ "under", 5 }, /* EQNMARK_UNDER */
+};
+
 /* ARGSUSED */
 enum rofferr
 eqn_read(struct eqn_node **epp, int ln, 
@@ -119,7 +137,8 @@ eqn_alloc(int pos, int line, struct mparse *parse)
 enum rofferr
 eqn_end(struct eqn_node *ep)
 {
-	struct eqn_box	*root;
+	struct eqn_box	*root, *last;
+	int		 c;
 
 	ep->eqn.root = root = 
 		mandoc_calloc(1, sizeof(struct eqn_box));
@@ -129,21 +148,40 @@ eqn_end(struct eqn_node *ep)
 		return(ROFF_IGN);
 
 	/*
-	 * Validate the expression.
-	 * Use the grammar found in the literature.
+	 * Run the parser.
+	 * If we return before reaching the end of our input, our scope
+	 * is still open somewhere.
+	 * If we return alright but don't have a symmetric scoping, then
+	 * something's not right either.
+	 * Otherwise, return the equation.
 	 */
 
-	return(eqn_box(ep, root) < 0 ? ROFF_IGN : ROFF_EQN);
+	if (0 == (c = eqn_box(ep, root, &last))) {
+		if (last != root) {
+			EQN_MSG(MANDOCERR_EQNSCOPE, ep);
+			c = 0;
+		}
+	} else if (c > 0)
+		EQN_MSG(MANDOCERR_EQNNSCOPE, ep);
+
+	return(0 == c ? ROFF_EQN : ROFF_IGN);
 }
 
 static int
-eqn_box(struct eqn_node *ep, struct eqn_box *last)
+eqn_box(struct eqn_node *ep, struct eqn_box *last, struct eqn_box **sv)
 {
 	size_t		 sz;
 	const char	*start;
-	int		 i, nextc;
+	int		 c, i, nextc;
 	struct eqn_box	*bp;
 
+	/* 
+	 * Mark our last level of subexpression. 
+	 * Also mark whether that the next node should be a
+	 * subexpression node.
+	 */
+
+	*sv = last;
 	nextc = 1;
 again:
 	if (NULL == (start = eqn_nexttok(ep, &sz)))
@@ -160,19 +198,48 @@ again:
 		goto again;
 	} 
 
-	bp = mandoc_calloc(1, sizeof(struct eqn_box));
-	bp->type = EQN_TEXT;
+	for (i = 0; i < (int)EQNMARK__MAX; i++) {
+		if (eqnmarks[i].sz != sz)
+			continue;
+		if (strncmp(eqnmarks[i].name, start, sz))
+			continue;
+		last->mark = (enum eqn_markt)i;
+		goto again;
+	}
 
+	/* Exit this [hopefully] subexpression. */
+
+	if (sz == 1 && 0 == strncmp("}", start, 1)) 
+		return(1);
+
+	bp = mandoc_calloc(1, sizeof(struct eqn_box));
 	if (nextc)
 		last->child = bp;
 	else
 		last->next = bp;
 
+	last = bp;
+
+	/* 
+	 * See if we're to open a new subexpression.
+	 * If so, mark our node as such and descend.
+	 */
+
+	if (sz == 1 && 0 == strncmp("{", start, 1)) {
+		bp->type = EQN_SUBEXPR;
+		c = eqn_box(ep, bp, sv);
+
+		nextc = 0;
+		goto again;
+	}
+
+	/* A regular text node. */
+
+	bp->type = EQN_TEXT;
 	bp->text = mandoc_malloc(sz + 1);
 	*bp->text = '\0';
 	strlcat(bp->text, start, sz + 1);
 
-	last = bp;
 	nextc = 0;
 	goto again;
 }