===================================================================
RCS file: /cvs/mandoc/Attic/validate.c,v
retrieving revision 1.19
retrieving revision 1.28
diff -u -p -r1.19 -r1.28
--- mandoc/Attic/validate.c	2009/01/08 15:05:50	1.19
+++ mandoc/Attic/validate.c	2009/01/14 11:58:24	1.28
@@ -1,4 +1,4 @@
-/* $Id: validate.c,v 1.19 2009/01/08 15:05:50 kristaps Exp $ */
+/* $Id: validate.c,v 1.28 2009/01/14 11:58:24 kristaps Exp $ */
 /*
  * Copyright (c) 2008 Kristaps Dzonsons <kristaps@kth.se>
  *
@@ -27,115 +27,155 @@ typedef	int	(*v_post)(struct mdoc *);
 
 
 struct	valids {
-	v_pre	 pre;
+	v_pre	*pre;
 	v_post	*post;
 };
 
 
-static	int	pre_sh(struct mdoc *, struct mdoc_node *);
-static	int	post_headchild_err_ge1(struct mdoc *);
-static	int	post_headchild_err_le8(struct mdoc *);
-static	int	post_bodychild_warn_ge1(struct mdoc *);
+static	int	pre_display(struct mdoc *, struct mdoc_node *);
+static	int	pre_bd(struct mdoc *, struct mdoc_node *);
+static	int	pre_bl(struct mdoc *, struct mdoc_node *);
+static	int	pre_it(struct mdoc *, struct mdoc_node *);
+static	int	pre_prologue(struct mdoc *, struct mdoc_node *);
+static	int	pre_prologue(struct mdoc *, struct mdoc_node *);
+static	int	pre_prologue(struct mdoc *, struct mdoc_node *);
 
-static v_post	posts_sh[] = { post_headchild_err_ge1, 
-			post_bodychild_warn_ge1, 
-			post_headchild_err_le8, NULL };
+static	int	headchild_err_ge1(struct mdoc *);
+static	int	headchild_warn_ge1(struct mdoc *);
+static	int	headchild_err_eq0(struct mdoc *);
+static	int	elemchild_err_eq0(struct mdoc *);
+static	int	elemchild_err_ge1(struct mdoc *);
+static	int	elemchild_warn_eq0(struct mdoc *);
+static	int	bodychild_warn_ge1(struct mdoc *);
+static	int	bodychild_err_eq0(struct mdoc *);
+static	int	elemchild_warn_ge1(struct mdoc *);
+static	int	post_sh(struct mdoc *);
+static	int	post_bl(struct mdoc *);
+static	int	post_it(struct mdoc *);
 
+static	v_pre	pres_prologue[] = { pre_prologue, NULL };
+static	v_pre	pres_d1[] = { pre_display, NULL };
+static	v_pre	pres_bd[] = { pre_display, pre_bd, NULL };
+static	v_pre	pres_bl[] = { pre_bl, NULL };
+static	v_pre	pres_it[] = { pre_it, NULL };
 
+static	v_post	posts_bd[] = { headchild_err_eq0, bodychild_warn_ge1, NULL };
+static	v_post	posts_text[] = { elemchild_err_ge1, NULL };
+static	v_post	posts_wtext[] = { elemchild_warn_ge1, NULL };
+static	v_post	posts_notext[] = { elemchild_err_eq0, NULL };
+static	v_post	posts_wline[] = { headchild_warn_ge1, bodychild_err_eq0, NULL };
+static	v_post	posts_sh[] = { headchild_err_ge1, bodychild_warn_ge1, post_sh, NULL };
+static	v_post	posts_bl[] = { headchild_err_eq0, bodychild_warn_ge1, post_bl, NULL };
+static	v_post	posts_it[] = { post_it, NULL };
+static	v_post	posts_ss[] = { headchild_err_ge1, NULL };
+static	v_post	posts_pp[] = { elemchild_warn_eq0, NULL };
+static	v_post	posts_d1[] = { headchild_err_ge1, NULL };
+
+
 const	struct valids mdoc_valids[MDOC_MAX] = {
 	{ NULL, NULL }, /* \" */
-	{ NULL, NULL }, /* Dd */ /* TODO: pre: ordering, repetition */
-	{ NULL, NULL }, /* Dt */ /* TODO ... */
-	{ NULL, NULL }, /* Os */ /* TODO ... */
-	{ pre_sh, posts_sh }, /* Sh */ /* FIXME: preceding Pp. */
-	{ NULL, NULL }, /* Ss */ /* FIXME: preceding Pp. */
-	{ NULL, NULL }, /* Pp */ 
-	{ NULL, NULL }, /* D1 */
-	{ NULL, NULL }, /* Dl */
-	{ NULL, NULL }, /* Bd */ /* FIXME: preceding Pp. */
+	{ pres_prologue, posts_text }, /* Dd */
+	{ pres_prologue, NULL }, /* Dt */
+	{ pres_prologue, NULL }, /* Os */
+	/* FIXME: preceding Pp. */ 
+	/* FIXME: NAME section internal ordering. */
+	/* FIXME: can only be a child of root. */
+	{ NULL, posts_sh }, /* Sh */ 
+	/* FIXME: preceding Pp. */
+	/* FIXME: can only be a child of Sh. */
+	{ NULL, posts_ss }, /* Ss */ 
+	/* FIXME: proceeding... */
+	{ NULL, posts_pp }, /* Pp */ 
+	{ pres_d1, posts_d1 }, /* D1 */
+	{ pres_d1, posts_d1 }, /* Dl */
+	 /* FIXME: preceding Pp. */
+	{ pres_bd, posts_bd }, /* Bd */
 	{ NULL, NULL }, /* Ed */
-	{ NULL, NULL }, /* Bl */ /* FIXME: preceding Pp. */
+	/* FIXME: preceding Pp. */
+	{ pres_bl, posts_bl }, /* Bl */ 
 	{ NULL, NULL }, /* El */
-	{ NULL, NULL }, /* It */
-	{ NULL, NULL }, /* Ad */ 
-	{ NULL, NULL }, /* An */
+	{ pres_it, posts_it }, /* It */
+	{ NULL, posts_text }, /* Ad */ 
+	/* FIXME */
+	{ NULL, NULL }, /* An */ 
 	{ NULL, NULL }, /* Ar */
-	{ NULL, NULL }, /* Cd */
+
+	{ NULL, posts_text }, /* Cd */ /* FIXME: section 4 only. */
 	{ NULL, NULL }, /* Cm */
-	{ NULL, NULL }, /* Dv */ 
-	{ NULL, NULL }, /* Er */ 
-	{ NULL, NULL }, /* Ev */ 
-	{ NULL, NULL }, /* Ex */
-	{ NULL, NULL }, /* Fa */ 
-	{ NULL, NULL }, /* Fd */ 
+	{ NULL, posts_text }, /* Dv */ 
+	{ NULL, posts_text }, /* Er */ /* FIXME: section 2 only. */
+	{ NULL, posts_text }, /* Ev */ 
+	{ NULL, posts_notext }, /* Ex */ /* FIXME: sections 1,6,8 only. */ /* -std required */
+	{ NULL, posts_text }, /* Fa */ 
+	{ NULL, NULL }, /* Fd */ /* FIXME: SYNOPSIS section. */
 	{ NULL, NULL }, /* Fl */
-	{ NULL, NULL }, /* Fn */ 
+	{ NULL, posts_text }, /* Fn */ 
 	{ NULL, NULL }, /* Ft */ 
-	{ NULL, NULL }, /* Ic */ 
-	{ NULL, NULL }, /* In */ 
-	{ NULL, NULL }, /* Li */
-	{ NULL, NULL }, /* Nd */ 
-	{ NULL, NULL }, /* Nm */ 
-	{ NULL, NULL }, /* Op */
+	{ NULL, posts_text }, /* Ic */ 
+	{ NULL, posts_wtext }, /* In */ 
+	{ NULL, posts_text }, /* Li */
+	{ NULL, posts_wtext }, /* Nd */
+	{ NULL, NULL }, /* Nm */  /* FIXME: If name not set? */
+	{ NULL, posts_wline }, /* Op */
 	{ NULL, NULL }, /* Ot */
 	{ NULL, NULL }, /* Pa */
-	{ NULL, NULL }, /* Rv */
-	{ NULL, NULL }, /* St */
-	{ NULL, NULL }, /* Va */
-	{ NULL, NULL }, /* Vt */ 
-	{ NULL, NULL }, /* Xr */
-	{ NULL, NULL }, /* %A */
-	{ NULL, NULL }, /* %B */
-	{ NULL, NULL }, /* %D */
-	{ NULL, NULL }, /* %I */
-	{ NULL, NULL }, /* %J */
-	{ NULL, NULL }, /* %N */
-	{ NULL, NULL }, /* %O */
-	{ NULL, NULL }, /* %P */
-	{ NULL, NULL }, /* %R */
-	{ NULL, NULL }, /* %T */
-	{ NULL, NULL }, /* %V */
+	{ NULL, posts_notext }, /* Rv */ /* -std required */
+	{ NULL, posts_notext }, /* St */ /* arg required */
+	{ NULL, posts_text }, /* Va */
+	{ NULL, posts_text }, /* Vt */ 
+	{ NULL, NULL }, /* Xr */ /* FIXME */
+	{ NULL, posts_text }, /* %A */
+	{ NULL, posts_text }, /* %B */
+	{ NULL, posts_text }, /* %D */
+	{ NULL, posts_text }, /* %I */
+	{ NULL, posts_text }, /* %J */
+	{ NULL, posts_text }, /* %N */
+	{ NULL, posts_text }, /* %O */
+	{ NULL, posts_text }, /* %P */
+	{ NULL, posts_text }, /* %R */
+	{ NULL, posts_text }, /* %T */
+	{ NULL, posts_text }, /* %V */
 	{ NULL, NULL }, /* Ac */
 	{ NULL, NULL }, /* Ao */
-	{ NULL, NULL }, /* Aq */
+	{ NULL, posts_wline }, /* Aq */
 	{ NULL, NULL }, /* At */ /* FIXME */
 	{ NULL, NULL }, /* Bc */
 	{ NULL, NULL }, /* Bf */ 
 	{ NULL, NULL }, /* Bo */
-	{ NULL, NULL }, /* Bq */
+	{ NULL, posts_wline }, /* Bq */
 	{ NULL, NULL }, /* Bsx */
 	{ NULL, NULL }, /* Bx */
-	{ NULL, NULL }, /* Db */
+	{ NULL, NULL }, /* Db */ /* FIXME: boolean */
 	{ NULL, NULL }, /* Dc */
 	{ NULL, NULL }, /* Do */
-	{ NULL, NULL }, /* Dq */
+	{ NULL, posts_wline }, /* Dq */
 	{ NULL, NULL }, /* Ec */
 	{ NULL, NULL }, /* Ef */ /* -symbolic, etc. */
-	{ NULL, NULL }, /* Em */ 
+	{ NULL, posts_text }, /* Em */ 
 	{ NULL, NULL }, /* Eo */
 	{ NULL, NULL }, /* Fx */
-	{ NULL, NULL }, /* Ms */
-	{ NULL, NULL }, /* No */
-	{ NULL, NULL }, /* Ns */
+	{ NULL, posts_text }, /* Ms */ /* FIXME: which symbols? */
+	{ NULL, posts_notext }, /* No */
+	{ NULL, posts_notext }, /* Ns */
 	{ NULL, NULL }, /* Nx */
 	{ NULL, NULL }, /* Ox */
 	{ NULL, NULL }, /* Pc */
-	{ NULL, NULL }, /* Pf */ /* 2 or more arguments */
+	{ NULL, NULL }, /* Pf */ /* FIXME: 2 or more arguments */
 	{ NULL, NULL }, /* Po */
-	{ NULL, NULL }, /* Pq */ /* FIXME: ignore following Sh/Ss */
+	{ NULL, posts_wline }, /* Pq */ /* FIXME: ignore following Sh/Ss */
 	{ NULL, NULL }, /* Qc */
-	{ NULL, NULL }, /* Ql */
+	{ NULL, posts_wline }, /* Ql */
 	{ NULL, NULL }, /* Qo */
-	{ NULL, NULL }, /* Qq */
+	{ NULL, posts_wline }, /* Qq */
 	{ NULL, NULL }, /* Re */
 	{ NULL, NULL }, /* Rs */
 	{ NULL, NULL }, /* Sc */
 	{ NULL, NULL }, /* So */
-	{ NULL, NULL }, /* Sq */
-	{ NULL, NULL }, /* Sm */
-	{ NULL, NULL }, /* Sx */
-	{ NULL, NULL }, /* Sy */
-	{ NULL, NULL }, /* Tn */
+	{ NULL, posts_wline }, /* Sq */
+	{ NULL, NULL }, /* Sm */ /* FIXME: boolean */
+	{ NULL, posts_text }, /* Sx */
+	{ NULL, posts_text }, /* Sy */
+	{ NULL, posts_text }, /* Tn */
 	{ NULL, NULL }, /* Ux */
 	{ NULL, NULL }, /* Xc */
 	{ NULL, NULL }, /* Xo */
@@ -145,117 +185,510 @@ const	struct valids mdoc_valids[MDOC_MAX] = {
 	{ NULL, NULL }, /* Oc */
 	{ NULL, NULL }, /* Bk */
 	{ NULL, NULL }, /* Ek */
-	{ NULL, NULL }, /* Bt */
+	{ NULL, posts_notext }, /* Bt */
 	{ NULL, NULL }, /* Hf */
 	{ NULL, NULL }, /* Fr */
-	{ NULL, NULL }, /* Ud */
+	{ NULL, posts_notext }, /* Ud */
 };
 
 
 static int
-post_bodychild_warn_ge1(struct mdoc *mdoc)
+bodychild_err_eq0(struct mdoc *mdoc)
 {
 
 	if (MDOC_BODY != mdoc->last->type)
 		return(1);
+	if (NULL == mdoc->last->child)
+		return(1);
+	return(mdoc_warn(mdoc, WARN_ARGS_EQ0));
+}
+
+
+static int
+bodychild_warn_ge1(struct mdoc *mdoc)
+{
+
+	if (MDOC_BODY != mdoc->last->type)
+		return(1);
 	if (mdoc->last->child)
 		return(1);
+	return(mdoc_warn(mdoc, WARN_ARGS_GE1));
+}
 
+
+static int
+elemchild_warn_eq0(struct mdoc *mdoc)
+{
+
+	assert(MDOC_ELEM == mdoc->last->type);
+	if (NULL == mdoc->last->child)
+		return(1);
+	return(mdoc_pwarn(mdoc, mdoc->last->child->line,
+			mdoc->last->child->pos, WARN_ARGS_EQ0));
+}
+
+
+static int
+elemchild_warn_ge1(struct mdoc *mdoc)
+{
+
+	assert(MDOC_ELEM == mdoc->last->type);
+	if (mdoc->last->child)
+		return(1);
 	return(mdoc_warn(mdoc, WARN_ARGS_GE1));
 }
 
 
 static int
-post_headchild_err_ge1(struct mdoc *mdoc)
+elemchild_err_eq0(struct mdoc *mdoc)
 {
 
+	assert(MDOC_ELEM == mdoc->last->type);
+	if (NULL == mdoc->last->child)
+		return(1);
+	return(mdoc_err(mdoc, ERR_ARGS_EQ0));
+}
+
+
+static int
+elemchild_err_ge1(struct mdoc *mdoc)
+{
+
+	assert(MDOC_ELEM == mdoc->last->type);
+	if (mdoc->last->child)
+		return(1);
+	return(mdoc_err(mdoc, ERR_ARGS_GE1));
+}
+
+
+static int
+headchild_err_eq0(struct mdoc *mdoc)
+{
+
 	if (MDOC_HEAD != mdoc->last->type)
 		return(1);
+	if (NULL == mdoc->last->child)
+		return(1);
+	return(mdoc_perr(mdoc, mdoc->last->child->line,
+			mdoc->last->child->pos, ERR_ARGS_EQ0));
+}
+
+
+static int
+headchild_warn_ge1(struct mdoc *mdoc)
+{
+
+	if (MDOC_HEAD != mdoc->last->type)
+		return(1);
 	if (mdoc->last->child)
 		return(1);
+	return(mdoc_warn(mdoc, WARN_ARGS_GE1));
+}
+
+
+static int
+headchild_err_ge1(struct mdoc *mdoc)
+{
+
+	if (MDOC_HEAD != mdoc->last->type)
+		return(1);
+	if (mdoc->last->child)
+		return(1);
 	return(mdoc_err(mdoc, ERR_ARGS_GE1));
 }
 
 
 static int
-post_headchild_err_le8(struct mdoc *mdoc)
+pre_display(struct mdoc *mdoc, struct mdoc_node *node)
 {
-	int		  i;
 	struct mdoc_node *n;
 
-	if (MDOC_HEAD != mdoc->last->type)
+	if (MDOC_BLOCK != node->type)
 		return(1);
-	for (i = 0, n = mdoc->last->child; n; n = n->next, i++)
-		/* Do nothing. */ ;
-	if (i <= 8)
+
+	for (n = mdoc->last; n; n = n->parent) 
+		if (MDOC_BLOCK == n->type)
+			if (MDOC_Bd == n->tok)
+				break;
+	if (NULL == n)
 		return(1);
-	return(mdoc_err(mdoc, ERR_ARGS_LE8));
+	return(mdoc_verr(mdoc, node, ERR_SCOPE_NONEST));
 }
 
 
 static int
-pre_sh(struct mdoc *mdoc, struct mdoc_node *node)
+pre_bl(struct mdoc *mdoc, struct mdoc_node *node)
 {
+	int		 type, err;
+	struct mdoc_arg	*argv;
+	size_t		 i, argc;
 
+	if (MDOC_BLOCK != node->type)
+		return(1);
+	assert(MDOC_Bl == node->tok);
+
+	argv = NULL;
+	argc = node->data.block.argc; 
+
+	for (i = type = err = 0; i < argc; i++) {
+		argv = &node->data.block.argv[(int)i];
+		assert(argv);
+		switch (argv->arg) {
+		case (MDOC_Bullet):
+			/* FALLTHROUGH */
+		case (MDOC_Dash):
+			/* FALLTHROUGH */
+		case (MDOC_Enum):
+			/* FALLTHROUGH */
+		case (MDOC_Hyphen):
+			/* FALLTHROUGH */
+		case (MDOC_Item):
+			/* FALLTHROUGH */
+		case (MDOC_Tag):
+			/* FALLTHROUGH */
+		case (MDOC_Diag):
+			/* FALLTHROUGH */
+		case (MDOC_Hang):
+			/* FALLTHROUGH */
+		case (MDOC_Ohang):
+			/* FALLTHROUGH */
+		case (MDOC_Inset):
+			/* FALLTHROUGH */
+		case (MDOC_Column):
+			if (type)
+				err++;
+			type++;
+			break;
+		default:
+			break;
+		}
+	}
+	if (0 == type)
+		return(mdoc_err(mdoc, ERR_SYNTAX_ARGMISS));
+	if (0 == err)
+		return(1);
+	assert(argv);
+	return(mdoc_perr(mdoc, argv->line, 
+			argv->pos, ERR_SYNTAX_ARGBAD));
+}
+
+
+static int
+pre_bd(struct mdoc *mdoc, struct mdoc_node *node)
+{
+	int		 type, err;
+	struct mdoc_arg	*argv;
+	size_t		 i, argc;
+
+	if (MDOC_BLOCK != node->type)
+		return(1);
+	assert(MDOC_Bd == node->tok);
+
+	argv = NULL;
+	argc = node->data.block.argc;
+
+	for (err = i = type = 0; 0 == err && i < argc; i++) {
+		argv = &node->data.block.argv[(int)i];
+		assert(argv);
+		switch (argv->arg) {
+		case (MDOC_Ragged):
+			/* FALLTHROUGH */
+		case (MDOC_Unfilled):
+			/* FALLTHROUGH */
+		case (MDOC_Literal):
+			/* FALLTHROUGH */
+		case (MDOC_File):
+			if (type)
+				err++;
+			type++;
+			break;
+		default:
+			break;
+		}
+	}
+	if (0 == type)
+		return(mdoc_err(mdoc, ERR_SYNTAX_ARGMISS));
+	if (0 == err)
+		return(1);
+	assert(argv);
+	return(mdoc_perr(mdoc, argv->line, 
+			argv->pos, ERR_SYNTAX_ARGBAD));
+}
+
+
+static int
+pre_it(struct mdoc *mdoc, struct mdoc_node *node)
+{
+
+	if (MDOC_BLOCK != mdoc->last->type)
+		return(1);
+	assert(MDOC_It == mdoc->last->tok);
+
+	if (MDOC_BODY != mdoc->last->parent->type) 
+		return(mdoc_verr(mdoc, node, ERR_SYNTAX_PARENTBAD));
+	if (MDOC_Bl != mdoc->last->parent->tok)
+		return(mdoc_verr(mdoc, node, ERR_SYNTAX_PARENTBAD));
+
 	return(1);
 }
 
 
-int
-mdoc_valid_pre(struct mdoc *mdoc, struct mdoc_node *node)
+static int
+pre_prologue(struct mdoc *mdoc, struct mdoc_node *node)
 {
-	int		 t;
 
-	switch (node->type) {
-	case (MDOC_BODY):
-		t = mdoc->last->data.body.tok;
+	if (SEC_PROLOGUE != mdoc->sec_lastn)
+		return(mdoc_verr(mdoc, node, ERR_SEC_NPROLOGUE));
+	assert(MDOC_ELEM == node->type);
+
+	/* Check for ordering. */
+
+	switch (node->tok) {
+	case (MDOC_Os):
+		if (mdoc->meta.title[0] && mdoc->meta.date)
+			break;
+		return(mdoc_verr(mdoc, node, ERR_SEC_PROLOGUE_OO));
+	case (MDOC_Dt):
+		if (0 == mdoc->meta.title[0] && mdoc->meta.date)
+			break;
+		return(mdoc_verr(mdoc, node, ERR_SEC_PROLOGUE_OO));
+	case (MDOC_Dd):
+		if (0 == mdoc->meta.title[0] && 0 == mdoc->meta.date)
+			break;
+		return(mdoc_verr(mdoc, node, ERR_SEC_PROLOGUE_OO));
+	default:
+		abort();
+		/* NOTREACHED */
+	}
+
+	/* Check for repetition. */
+
+	switch (node->tok) {
+	case (MDOC_Os):
+		if (0 == mdoc->meta.os[0])
+			return(1);
 		break;
-	case (MDOC_ELEM):
-		t = mdoc->last->data.elem.tok;
+	case (MDOC_Dd):
+		if (0 == mdoc->meta.date)
+			return(1);
 		break;
-	case (MDOC_BLOCK):
-		t = mdoc->last->data.block.tok;
+	case (MDOC_Dt):
+		if (0 == mdoc->meta.title[0])
+			return(1);
 		break;
-	case (MDOC_HEAD):
-		t = mdoc->last->data.head.tok;
-		break;
 	default:
+		abort();
+		/* NOTREACHED */
+	}
+
+	return(mdoc_verr(mdoc, node, ERR_SEC_PROLOGUE_REP));
+}
+
+
+/* Warn if `Bl' type-specific syntax isn't reflected in items. */
+static int
+post_it(struct mdoc *mdoc)
+{
+	int		  type, sv;
+#define	TYPE_NONE	 (0)
+#define	TYPE_BODY	 (1)
+#define	TYPE_HEAD	 (2)
+	size_t		  i, argc;
+	struct mdoc_node *n;
+
+	if (MDOC_BLOCK != mdoc->last->type)
 		return(1);
+
+	assert(MDOC_It == mdoc->last->tok);
+
+	n = mdoc->last->parent;
+	assert(n);
+	assert(MDOC_Bl == n->tok);
+
+	n = n->parent;
+	assert(MDOC_BLOCK == n->type);
+	assert(MDOC_Bl == n->tok);
+
+	argc = n->data.block.argc;
+	type = TYPE_NONE;
+	
+	/* Some types require block-head, some not. */
+
+	for (i = 0; TYPE_NONE == type && i < argc; i++)
+		switch (n->data.block.argv[(int)i].arg) {
+		case (MDOC_Tag):
+			/* FALLTHROUGH */
+		case (MDOC_Diag):
+			/* FALLTHROUGH */
+		case (MDOC_Hang):
+			/* FALLTHROUGH */
+		case (MDOC_Ohang):
+			/* FALLTHROUGH */
+		case (MDOC_Inset):
+			type = TYPE_HEAD;
+			sv = n->data.block.argv[(int)i].arg;
+			break;
+		case (MDOC_Bullet):
+			/* FALLTHROUGH */
+		case (MDOC_Dash):
+			/* FALLTHROUGH */
+		case (MDOC_Enum):
+			/* FALLTHROUGH */
+		case (MDOC_Hyphen):
+			/* FALLTHROUGH */
+		case (MDOC_Item):
+			/* FALLTHROUGH */
+		case (MDOC_Column):
+			type = TYPE_BODY;
+			sv = n->data.block.argv[(int)i].arg;
+			break;
+		default:
+			break;
+		}
+
+	assert(TYPE_NONE != type);
+
+	if (TYPE_HEAD == type) {
+		if (NULL == (n = mdoc->last->data.block.head)) {
+			if ( ! mdoc_warn(mdoc, WARN_SYNTAX_EMPTYHEAD))
+				return(0);
+		} else if (NULL == n->child)
+			if ( ! mdoc_warn(mdoc, WARN_SYNTAX_EMPTYHEAD))
+				return(0);
+
+		if (NULL == (n = mdoc->last->data.block.body)) {
+			if ( ! mdoc_warn(mdoc, WARN_SYNTAX_EMPTYBODY))
+				return(0);
+		} else if (NULL == n->child)
+			if ( ! mdoc_warn(mdoc, WARN_SYNTAX_EMPTYBODY))
+				return(0);
+
+		return(1);
 	}
 
-	if (NULL == mdoc_valids[t].pre)
+	if (NULL == (n = mdoc->last->data.block.head)) {
+		if ( ! mdoc_warn(mdoc, WARN_SYNTAX_EMPTYHEAD))
+			return(0);
+	} else if (NULL == n->child)
+		if ( ! mdoc_warn(mdoc, WARN_SYNTAX_EMPTYHEAD))
+			return(0);
+
+	if ((n = mdoc->last->data.block.body) && n->child)
+		if ( ! mdoc_warn(mdoc, WARN_SYNTAX_NOBODY))
+			return(0);
+
+	if (MDOC_Column != sv) 
 		return(1);
-	return((*mdoc_valids[t].pre)(mdoc, node));
+
+	/* Make sure the number of columns is sane. */
+
+	sv = mdoc->last->parent->parent->data.block.argv->sz;
+	n = mdoc->last->data.block.head->child;
+
+	for (i = 0; n; n = n->next)
+		i++;
+
+	if (i == (size_t)sv)
+		return(1);
+	return(mdoc_err(mdoc, ERR_SYNTAX_ARGFORM));
+
+#undef	TYPE_NONE
+#undef	TYPE_BODY
+#undef	TYPE_HEAD
 }
 
 
-int
-mdoc_valid_post(struct mdoc *mdoc)
+/* Make sure that only `It' macros are our body-children. */
+static int
+post_bl(struct mdoc *mdoc)
 {
-	v_post		*p;
-	int		 t;
+	struct mdoc_node *n;
 
-	switch (mdoc->last->type) {
-	case (MDOC_BODY):
-		t = mdoc->last->data.body.tok;
+	if (MDOC_BODY != mdoc->last->type)
+		return(1);
+	assert(MDOC_Bl == mdoc->last->tok);
+
+	for (n = mdoc->last->child; n; n = n->next) {
+		if (MDOC_BLOCK == n->type) 
+			if (MDOC_It == n->tok)
+				continue;
 		break;
-	case (MDOC_ELEM):
-		t = mdoc->last->data.elem.tok;
-		break;
-	case (MDOC_BLOCK):
-		t = mdoc->last->data.block.tok;
-		break;
-	case (MDOC_HEAD):
-		t = mdoc->last->data.head.tok;
-		break;
-	default:
+	}
+	if (NULL == n)
 		return(1);
+	return(mdoc_verr(mdoc, n, ERR_SYNTAX_CHILDBAD));
+}
+
+
+/* Warn if conventional sections are out of order. */
+static int
+post_sh(struct mdoc *mdoc)
+{
+	enum mdoc_sec	  sec;
+	int		  i;
+	struct mdoc_node *n;
+	char		 *args[MDOC_LINEARG_MAX];
+
+	if (MDOC_HEAD != mdoc->last->type)
+		return(1);
+	
+	assert(MDOC_Sh == mdoc->last->tok);
+
+	n = mdoc->last->child;
+	assert(n);
+
+	for (i = 0; n && i < MDOC_LINEARG_MAX; n = n->next, i++) {
+		assert(MDOC_TEXT == n->type);
+		assert(NULL == n->child);
+		assert(n->data.text.string);
+		args[i] = n->data.text.string;
 	}
 
-	if (NULL == mdoc_valids[t].post)
+	sec = mdoc_atosec((size_t)i, (const char **)args);
+	if (SEC_CUSTOM == sec)
 		return(1);
+	if (sec > mdoc->sec_lastn)
+		return(1);
 
-	for (p = mdoc_valids[t].post; *p; p++)
+	if (sec == mdoc->sec_lastn)
+		return(mdoc_warn(mdoc, WARN_SEC_REP));
+	return(mdoc_warn(mdoc, WARN_SEC_OO));
+}
+
+
+int
+mdoc_valid_pre(struct mdoc *mdoc, struct mdoc_node *node)
+{
+	v_pre		*p;
+
+	/* TODO: character-escape checks. */
+
+	if (MDOC_TEXT == node->type)
+		return(1);
+	assert(MDOC_ROOT != node->type);
+
+	if (NULL == mdoc_valids[node->tok].pre)
+		return(1);
+	for (p = mdoc_valids[node->tok].pre; *p; p++)
+		if ( ! (*p)(mdoc, node)) 
+			return(0);
+	return(1);
+}
+
+
+int
+mdoc_valid_post(struct mdoc *mdoc)
+{
+	v_post		*p;
+
+	if (MDOC_TEXT == mdoc->last->type)
+		return(1);
+	if (MDOC_ROOT == mdoc->last->type)
+		return(1);
+
+	if (NULL == mdoc_valids[mdoc->last->tok].post)
+		return(1);
+	for (p = mdoc_valids[mdoc->last->tok].post; *p; p++)
 		if ( ! (*p)(mdoc)) 
 			return(0);