Added man validator, renamed mdoc validator.

1 files changed, 1396 insertions, 0 deletions

diff --git a/mdoc_validate.c b/mdoc_validate.c
new file mode 100644
index 00000000..ca2230a9
--- /dev/null
+++ b/mdoc_validate.c
@@ -0,0 +1,1396 @@
+/* $Id: mdoc_validate.c,v 1.1 2009/03/25 15:17:49 kristaps Exp $ */
+/*
+ * Copyright (c) 2008, 2009 Kristaps Dzonsons <kristaps@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the
+ * above copyright notice and this permission notice appear in all
+ * copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
+ * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
+ * AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
+ * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
+ * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+#include <sys/types.h>
+
+#include <assert.h>
+#include <ctype.h>
+#include <stdarg.h>
+#include <stdlib.h>
+
+#include "libmdoc.h"
+
+/* FIXME: .Bl -diag can't have non-text children in HEAD. */
+/* TODO: ignoring Pp (it's superfluous in some invocations). */
+
+/*
+ * Pre- and post-validate macros as they're parsed.  Pre-validation
+ * occurs when the macro has been detected and its arguments parsed.
+ * Post-validation occurs when all child macros have also been parsed.
+ * In the ELEMENT case, this is simply the parameters of the macro; in
+ * the BLOCK case, this is the HEAD, BODY, TAIL and so on.
+ */
+
+#define	PRE_ARGS	struct mdoc *mdoc, const struct mdoc_node *n
+#define	POST_ARGS	struct mdoc *mdoc
+
+enum	merr {
+	EESCAPE,
+	EPRINT,
+	ENODATA,
+	ENOPROLOGUE,
+	ELINE,
+	EATT,
+	ENAME,
+	ELISTTYPE,
+	EDISPTYPE,
+	EMULTIDISP,
+	EMULTILIST,
+	EARGREP,
+	EBOOL,
+	ENESTDISP
+};
+
+enum	mwarn {
+	WESCAPE,
+	WWRONGMSEC,
+	WSECOOO,
+	WSECREP,
+	WBADSTAND,
+	WNAMESECINC,
+	WNOMULTILINE,
+	WMULTILINE,
+	WLINE,
+	WNOLINE,
+	WPROLOOO,
+	WPROLREP,
+	WARGVAL,
+	WBADSEC,
+	WBADMSEC
+};
+
+typedef	int	(*v_pre)(PRE_ARGS);
+typedef	int	(*v_post)(POST_ARGS);
+
+struct	valids {
+	v_pre	*pre;
+	v_post	*post;
+};
+
+/* Utility checks. */
+
+static	int	pwarn(struct mdoc *, int, int, enum mwarn);
+static	int	perr(struct mdoc *, int, int, enum merr);
+static	int	check_parent(PRE_ARGS, int, enum mdoc_type);
+static	int	check_msec(PRE_ARGS, ...);
+static	int	check_sec(PRE_ARGS, ...);
+static	int	check_stdarg(PRE_ARGS);
+static	int	check_text(struct mdoc *, int, int, const char *);
+static	int	check_argv(struct mdoc *, 
+			const struct mdoc_node *,
+			const struct mdoc_argv *);
+static	int	check_args(struct mdoc *, 
+			const struct mdoc_node *);
+static	int	err_child_lt(struct mdoc *, const char *, int);
+static	int	warn_child_lt(struct mdoc *, const char *, int);
+static	int	err_child_gt(struct mdoc *, const char *, int);
+static	int	warn_child_gt(struct mdoc *, const char *, int);
+static	int	err_child_eq(struct mdoc *, const char *, int);
+static	int	warn_child_eq(struct mdoc *, const char *, int);
+static	inline int count_child(struct mdoc *);
+static	inline int warn_count(struct mdoc *, const char *, 
+			int, const char *, int);
+static	inline int err_count(struct mdoc *, const char *, 
+			int, const char *, int);
+static	int	pre_an(PRE_ARGS);
+static	int	pre_bd(PRE_ARGS);
+static	int	pre_bl(PRE_ARGS);
+static	int	pre_cd(PRE_ARGS);
+static	int	pre_dd(PRE_ARGS);
+static	int	pre_display(PRE_ARGS);
+static	int	pre_dt(PRE_ARGS);
+static	int	pre_er(PRE_ARGS);
+static	int	pre_ex(PRE_ARGS);
+static	int	pre_fd(PRE_ARGS);
+static	int	pre_it(PRE_ARGS);
+static	int	pre_lb(PRE_ARGS);
+static	int	pre_os(PRE_ARGS);
+static	int	pre_prologue(PRE_ARGS);
+static	int	pre_rv(PRE_ARGS);
+static	int	pre_sh(PRE_ARGS);
+static	int	pre_ss(PRE_ARGS);
+static	int	herr_ge1(POST_ARGS);
+static	int	hwarn_le1(POST_ARGS);
+static	int	herr_eq0(POST_ARGS);
+static	int	eerr_eq0(POST_ARGS);
+static	int	eerr_le2(POST_ARGS);
+static	int	eerr_eq1(POST_ARGS);
+static	int	eerr_ge1(POST_ARGS);
+static	int	ewarn_eq0(POST_ARGS);
+static	int	ewarn_eq1(POST_ARGS);
+static	int	bwarn_ge1(POST_ARGS);
+static	int	hwarn_eq1(POST_ARGS);
+static	int	ewarn_ge1(POST_ARGS);
+static	int	ebool(POST_ARGS);
+
+static	int	post_an(POST_ARGS);
+static	int	post_args(POST_ARGS);
+static	int	post_at(POST_ARGS);
+static	int	post_bf(POST_ARGS);
+static	int	post_bl(POST_ARGS);
+static	int	post_it(POST_ARGS);
+static	int	post_nm(POST_ARGS);
+static	int	post_root(POST_ARGS);
+static	int	post_sh(POST_ARGS);
+static	int	post_sh_body(POST_ARGS);
+static	int	post_sh_head(POST_ARGS);
+static	int	post_st(POST_ARGS);
+
+#define	mwarn(m, t) nwarn((m), (m)->last, (t))
+#define	merr(m, t) nerr((m), (m)->last, (t))
+#define	nwarn(m, n, t) pwarn((m), (n)->line, (n)->pos, (t))
+#define	nerr(m, n, t) perr((m), (n)->line, (n)->pos, (t))
+
+static	v_pre	pres_an[] = { pre_an, NULL };
+static	v_pre	pres_bd[] = { pre_display, pre_bd, NULL };
+static	v_pre	pres_bl[] = { pre_bl, NULL };
+static	v_pre	pres_cd[] = { pre_cd, NULL };
+static	v_pre	pres_dd[] = { pre_prologue, pre_dd, NULL };
+static	v_pre	pres_d1[] = { pre_display, NULL };
+static	v_pre	pres_dt[] = { pre_prologue, pre_dt, NULL };
+static	v_pre	pres_er[] = { pre_er, NULL };
+static	v_pre	pres_ex[] = { pre_ex, NULL };
+static	v_pre	pres_fd[] = { pre_fd, NULL };
+static	v_pre	pres_it[] = { pre_it, NULL };
+static	v_pre	pres_lb[] = { pre_lb, NULL };
+static	v_pre	pres_os[] = { pre_prologue, pre_os, NULL };
+static	v_pre	pres_rv[] = { pre_rv, NULL };
+static	v_pre	pres_sh[] = { pre_sh, NULL };
+static	v_pre	pres_ss[] = { pre_ss, NULL };
+static	v_post	posts_bool[] = { eerr_eq1, ebool, NULL };
+static	v_post	posts_bd[] = { herr_eq0, bwarn_ge1, NULL };
+static	v_post	posts_text[] = { eerr_ge1, NULL };
+static	v_post	posts_wtext[] = { ewarn_ge1, NULL };
+static	v_post	posts_notext[] = { eerr_eq0, NULL };
+static	v_post	posts_wline[] = { bwarn_ge1, herr_eq0, NULL };
+static	v_post	posts_sh[] = { herr_ge1, bwarn_ge1, post_sh, NULL };
+static	v_post	posts_bl[] = { herr_eq0, bwarn_ge1, post_bl, NULL };
+static	v_post	posts_it[] = { post_it, NULL };
+static	v_post	posts_in[] = { ewarn_eq1, NULL };
+static	v_post	posts_ss[] = { herr_ge1, NULL };
+static	v_post	posts_pf[] = { eerr_eq1, NULL };
+static	v_post	posts_lb[] = { eerr_eq1, NULL };
+static	v_post	posts_st[] = { eerr_eq1, post_st, NULL };
+static	v_post	posts_pp[] = { ewarn_eq0, NULL };
+static	v_post	posts_ex[] = { eerr_eq0, post_args, NULL };
+static	v_post	posts_rv[] = { eerr_eq0, post_args, NULL };
+static	v_post	posts_an[] = { post_an, NULL };
+static	v_post	posts_at[] = { post_at, NULL };
+static	v_post	posts_xr[] = { eerr_ge1, eerr_le2, NULL };
+static	v_post	posts_nm[] = { post_nm, NULL };
+static	v_post	posts_bf[] = { hwarn_le1, post_bf, NULL };
+static	v_post	posts_fo[] = { hwarn_eq1, bwarn_ge1, NULL };
+
+const	struct valids mdoc_valids[MDOC_MAX] = {
+	{ NULL, NULL }, 			/* \" */
+	{ pres_dd, posts_text },		/* Dd */
+	{ pres_dt, NULL },			/* Dt */
+	{ pres_os, NULL },			/* Os */
+	{ pres_sh, posts_sh },			/* Sh */ 
+	{ pres_ss, posts_ss },			/* Ss */ 
+	{ NULL, posts_pp },			/* Pp */ 
+	{ pres_d1, posts_wline },		/* D1 */
+	{ pres_d1, posts_wline },		/* Dl */
+	{ pres_bd, posts_bd },			/* Bd */
+	{ NULL, NULL },				/* Ed */
+	{ pres_bl, posts_bl },			/* Bl */ 
+	{ NULL, NULL },				/* El */
+	{ pres_it, posts_it },			/* It */
+	{ NULL, posts_text },			/* Ad */ 
+	{ pres_an, posts_an },			/* An */ 
+	{ NULL, NULL },				/* Ar */
+	{ pres_cd, posts_text },		/* Cd */ 
+	{ NULL, NULL },				/* Cm */
+	{ NULL, NULL },				/* Dv */ 
+	{ pres_er, posts_text },		/* Er */ 
+	{ NULL, NULL },				/* Ev */ 
+	{ pres_ex, posts_ex },			/* Ex */ 
+	{ NULL, NULL },				/* Fa */ 
+	{ pres_fd, posts_wtext },		/* Fd */
+	{ NULL, NULL },				/* Fl */
+	{ NULL, posts_text },			/* Fn */ 
+	{ NULL, posts_wtext },			/* Ft */ 
+	{ NULL, posts_text },			/* Ic */ 
+	{ NULL, posts_in },			/* In */ 
+	{ NULL, NULL },				/* Li */
+	{ NULL, posts_wtext },			/* Nd */
+	{ NULL, posts_nm },			/* Nm */
+	{ NULL, posts_wline },			/* Op */
+	{ NULL, NULL },				/* Ot */
+	{ NULL, NULL },				/* Pa */
+	{ pres_rv, posts_rv },			/* Rv */
+	{ NULL, posts_st },			/* St */ 
+	{ NULL, NULL },				/* Va */
+	{ NULL, posts_text },			/* Vt */ 
+	{ NULL, posts_xr },			/* Xr */ 
+	{ 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, posts_wline },			/* Aq */
+	{ NULL, posts_at },			/* At */ 
+	{ NULL, NULL },				/* Bc */
+	{ NULL, posts_bf },			/* Bf */
+	{ NULL, NULL },				/* Bo */
+	{ NULL, posts_wline },			/* Bq */
+	{ NULL, NULL },				/* Bsx */
+	{ NULL, NULL },				/* Bx */
+	{ NULL, posts_bool },			/* Db */
+	{ NULL, NULL },				/* Dc */
+	{ NULL, NULL },				/* Do */
+	{ NULL, posts_wline },			/* Dq */
+	{ NULL, NULL },				/* Ec */
+	{ NULL, NULL },				/* Ef */ 
+	{ NULL, NULL },				/* Em */ 
+	{ NULL, NULL },				/* Eo */
+	{ NULL, NULL },				/* Fx */
+	{ NULL, posts_text },			/* Ms */ 
+	{ NULL, posts_notext },			/* No */
+	{ NULL, posts_notext },			/* Ns */
+	{ NULL, NULL },				/* Nx */
+	{ NULL, NULL },				/* Ox */
+	{ NULL, NULL },				/* Pc */
+	{ NULL, posts_pf },			/* Pf */
+	{ NULL, NULL },				/* Po */
+	{ NULL, posts_wline },			/* Pq */
+	{ NULL, NULL },				/* Qc */
+	{ NULL, posts_wline },			/* Ql */
+	{ NULL, NULL },				/* Qo */
+	{ NULL, posts_wline },			/* Qq */
+	{ NULL, NULL },				/* Re */
+	{ NULL, posts_wline },			/* Rs */
+	{ NULL, NULL },				/* Sc */
+	{ NULL, NULL },				/* So */
+	{ NULL, posts_wline },			/* Sq */
+	{ NULL, posts_bool },			/* Sm */ 
+	{ NULL, posts_text },			/* Sx */
+	{ NULL, posts_text },			/* Sy */
+	{ NULL, posts_text },			/* Tn */
+	{ NULL, NULL },				/* Ux */
+	{ NULL, NULL },				/* Xc */
+	{ NULL, NULL },				/* Xo */
+	{ NULL, posts_fo },			/* Fo */ 
+	{ NULL, NULL },				/* Fc */ 
+	{ NULL, NULL },				/* Oo */
+	{ NULL, NULL },				/* Oc */
+	{ NULL, posts_wline },			/* Bk */
+	{ NULL, NULL },				/* Ek */
+	{ NULL, posts_notext },			/* Bt */
+	{ NULL, NULL },				/* Hf */
+	{ NULL, NULL },				/* Fr */
+	{ NULL, posts_notext },			/* Ud */
+	{ pres_lb, posts_lb },			/* Lb */
+	{ NULL, NULL },				/* Ap */
+	{ NULL, posts_pp },			/* Lp */ 
+	{ NULL, posts_text },			/* Lk */ 
+	{ NULL, posts_text },			/* Mt */ 
+	{ NULL, posts_wline },			/* Brq */ 
+	{ NULL, NULL },				/* Bro */ 
+	{ NULL, NULL },				/* Brc */ 
+	{ NULL, posts_text },			/* %C */
+	{ NULL, NULL },				/* Es */
+	{ NULL, NULL },				/* En */
+	{ NULL, NULL },				/* Dx */
+	{ NULL, posts_text },			/* %Q */
+};
+
+
+int
+mdoc_valid_pre(struct mdoc *mdoc, 
+		const struct mdoc_node *n)
+{
+	v_pre		*p;
+	int		 line, pos;
+	const char	*tp;
+
+	if (MDOC_TEXT == n->type) {
+		tp = n->string;
+		line = n->line;
+		pos = n->pos;
+		return(check_text(mdoc, line, pos, tp));
+	}
+
+	if ( ! check_args(mdoc, n))
+		return(0);
+	if (NULL == mdoc_valids[n->tok].pre)
+		return(1);
+	for (p = mdoc_valids[n->tok].pre; *p; p++)
+		if ( ! (*p)(mdoc, n)) 
+			return(0);
+	return(1);
+}
+
+
+int
+mdoc_valid_post(struct mdoc *mdoc)
+{
+	v_post		*p;
+
+	/*
+	 * This check occurs after the macro's children have been filled
+	 * in: postfix validation.  Since this happens when we're
+	 * rewinding the scope tree, it's possible to have multiple
+	 * invocations (as by design, for now), we set bit MDOC_VALID to
+	 * indicate that we've validated.
+	 */
+
+	if (MDOC_VALID & mdoc->last->flags)
+		return(1);
+	mdoc->last->flags |= MDOC_VALID;
+
+	if (MDOC_TEXT == mdoc->last->type)
+		return(1);
+	if (MDOC_ROOT == mdoc->last->type)
+		return(post_root(mdoc));
+
+	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);
+
+	return(1);
+}
+
+
+static int
+perr(struct mdoc *m, int line, int pos, enum merr type)
+{
+	char		 *p;
+	
+	p = NULL;
+	switch (type) {
+	case (EESCAPE):
+		p = "invalid escape sequence";
+		break;
+	case (EPRINT):
+		p = "invalid character";
+		break;
+	case (ENESTDISP):
+		p = "displays may not be nested";
+		break;
+	case (EBOOL):
+		p = "expected boolean value";
+		break;
+	case (EARGREP):
+		p = "argument repeated";
+		break;
+	case (EMULTIDISP):
+		p = "multiple display types specified";
+		break;
+	case (EMULTILIST):
+		p = "multiple list types specified";
+		break;
+	case (ELISTTYPE):
+		p = "missing list type";
+		break;
+	case (EDISPTYPE):
+		p = "missing display type";
+		break;
+	case (ELINE):
+		p = "expected line arguments";
+		break;
+	case (ENOPROLOGUE):
+		p = "document has no prologue";
+		break;
+	case (ENODATA):
+		p = "document has no data";
+		break;
+	case (EATT):
+		p = "expected valid AT&T symbol";
+		break;
+	case (ENAME):
+		p = "default name not yet set";
+		break;
+	}
+	assert(p);
+	return(mdoc_perr(m, line, pos, p));
+}
+
+
+static int
+pwarn(struct mdoc *m, int line, int pos, enum mwarn type)
+{
+	char		 *p;
+	enum mdoc_warn	  c;
+
+	c = WARN_SYNTAX;
+	p = NULL;
+	switch (type) {
+	case (WBADMSEC):
+		p = "inappropriate manual section";
+		c = WARN_COMPAT;
+		break;
+	case (WBADSEC):
+		p = "inappropriate document section";
+		c = WARN_COMPAT;
+		break;
+	case (WARGVAL):
+		p = "argument value suggested";
+		c = WARN_COMPAT;
+		break;
+	case (WPROLREP):
+		p = "prologue macros repeated";
+		c = WARN_COMPAT;
+		break;
+	case (WPROLOOO):
+		p = "prologue macros out-of-order";
+		c = WARN_COMPAT;
+		break;
+	case (WESCAPE):
+		p = "invalid escape sequence";
+		break;
+	case (WNOLINE):
+		p = "suggested no line arguments";
+		break;
+	case (WLINE):
+		p = "suggested line arguments";
+		break;
+	case (WMULTILINE):
+		p = "suggested multi-line arguments";
+		break;
+	case (WNOMULTILINE):
+		p = "suggested no multi-line arguments";
+		break;
+	case (WWRONGMSEC):
+		p = "document section in wrong manual section";
+		c = WARN_COMPAT;
+		break;
+	case (WSECOOO):
+		p = "document section out of conventional order";
+		break;
+	case (WSECREP):
+		p = "document section repeated";
+		break;
+	case (WBADSTAND):
+		p = "unknown standard";
+		break;
+	case (WNAMESECINC):
+		p = "NAME section contents incomplete/badly-ordered";
+		break;
+	}
+	assert(p);
+	return(mdoc_pwarn(m, line, pos, c, p));
+}
+
+
+
+static inline int
+warn_count(struct mdoc *m, const char *k, 
+		int want, const char *v, int has)
+{
+
+	return(mdoc_warn(m, WARN_SYNTAX, 
+		"suggests %s %s %d (has %d)", v, k, want, has));
+}
+
+
+static inline int
+err_count(struct mdoc *m, const char *k,
+		int want, const char *v, int has)
+{
+
+	return(mdoc_err(m, 
+		"requires %s %s %d (has %d)", v, k, want, has));
+}
+
+
+static inline int
+count_child(struct mdoc *mdoc)
+{
+	int		  i;
+	struct mdoc_node *n;
+
+	for (i = 0, n = mdoc->last->child; n; n = n->next, i++)
+		/* Do nothing */ ;
+
+	return(i);
+}
+
+
+/*
+ * Build these up with macros because they're basically the same check
+ * for different inequalities.  Yes, this could be done with functions,
+ * but this is reasonable for now.
+ */
+
+#define CHECK_CHILD_DEFN(lvl, name, ineq) 			\
+static int 							\
+lvl##_child_##name(struct mdoc *mdoc, const char *p, int sz) 	\
+{ 								\
+	int i; 							\
+	if ((i = count_child(mdoc)) ineq sz) 			\
+		return(1); 					\
+	return(lvl##_count(mdoc, #ineq, sz, p, i)); 		\
+}
+
+#define CHECK_BODY_DEFN(name, lvl, func, num) 			\
+static int 							\
+b##lvl##_##name(POST_ARGS) 					\
+{ 								\
+	if (MDOC_BODY != mdoc->last->type) 			\
+		return(1); 					\
+	return(func(mdoc, "multi-line arguments", (num))); 	\
+}
+
+#define CHECK_ELEM_DEFN(name, lvl, func, num) 			\
+static int							\
+e##lvl##_##name(POST_ARGS) 					\
+{ 								\
+	assert(MDOC_ELEM == mdoc->last->type); 			\
+	return(func(mdoc, "line arguments", (num))); 		\
+}
+
+#define CHECK_HEAD_DEFN(name, lvl, func, num)			\
+static int 							\
+h##lvl##_##name(POST_ARGS) 					\
+{ 								\
+	if (MDOC_HEAD != mdoc->last->type) 			\
+		return(1); 					\
+	return(func(mdoc, "line arguments", (num)));	 	\
+}
+
+
+CHECK_CHILD_DEFN(warn, gt, >)			/* warn_child_gt() */
+CHECK_CHILD_DEFN(err, gt, >)			/* err_child_gt() */
+CHECK_CHILD_DEFN(warn, eq, ==)			/* warn_child_eq() */
+CHECK_CHILD_DEFN(err, eq, ==)			/* err_child_eq() */
+CHECK_CHILD_DEFN(err, lt, <)			/* err_child_lt() */
+CHECK_CHILD_DEFN(warn, lt, <)			/* warn_child_lt() */
+CHECK_BODY_DEFN(ge1, warn, warn_child_gt, 0)	/* bwarn_ge1() */
+CHECK_ELEM_DEFN(eq1, warn, warn_child_eq, 1)	/* ewarn_eq1() */
+CHECK_ELEM_DEFN(eq0, warn, warn_child_eq, 0)	/* ewarn_eq0() */
+CHECK_ELEM_DEFN(ge1, warn, warn_child_gt, 0)	/* ewarn_gt1() */
+CHECK_ELEM_DEFN(eq1, err, err_child_eq, 1)	/* eerr_eq1() */
+CHECK_ELEM_DEFN(le2, err, err_child_lt, 3)	/* eerr_le2() */
+CHECK_ELEM_DEFN(eq0, err, err_child_eq, 0)	/* eerr_eq0() */
+CHECK_ELEM_DEFN(ge1, err, err_child_gt, 0)	/* eerr_ge1() */
+CHECK_HEAD_DEFN(eq0, err, err_child_eq, 0)	/* herr_eq0() */
+CHECK_HEAD_DEFN(le1, warn, warn_child_lt, 2)	/* hwarn_le1() */
+CHECK_HEAD_DEFN(ge1, err, err_child_gt, 0)	/* herr_ge1() */
+CHECK_HEAD_DEFN(eq1, warn, warn_child_eq, 1)	/* hwarn_eq1() */
+
+
+static int
+check_stdarg(PRE_ARGS)
+{
+
+	if (n->args && 1 == n->args->argc)
+		if (MDOC_Std == n->args->argv[0].arg)
+			return(1);
+	return(nwarn(mdoc, n, WARGVAL));
+}
+
+
+static int
+check_sec(PRE_ARGS, ...)
+{
+	enum mdoc_sec	 sec;
+	va_list		 ap;
+
+	va_start(ap, n);
+
+	for (;;) {
+		/* LINTED */
+		sec = (enum mdoc_sec)va_arg(ap, int);
+		if (SEC_CUSTOM == sec)
+			break;
+		if (sec != mdoc->lastsec)
+			continue;
+		va_end(ap);
+		return(1);
+	}
+
+	va_end(ap);
+	return(nwarn(mdoc, n, WBADSEC));
+}
+
+
+static int
+check_msec(PRE_ARGS, ...)
+{
+	va_list		 ap;
+	int		 msec;
+
+	va_start(ap, n);
+	for (;;) {
+		/* LINTED */
+		if (0 == (msec = va_arg(ap, int)))
+			break;
+		if (msec != mdoc->meta.msec)
+			continue;
+		va_end(ap);
+		return(1);
+	}
+
+	va_end(ap);
+	return(nwarn(mdoc, n, WBADMSEC));
+}
+
+
+static int
+check_args(struct mdoc *m, const struct mdoc_node *n)
+{
+	int		 i;
+
+	if (NULL == n->args)
+		return(1);
+
+	assert(n->args->argc);
+	for (i = 0; i < (int)n->args->argc; i++)
+		if ( ! check_argv(m, n, &n->args->argv[i]))
+			return(0);
+
+	return(1);
+}
+
+
+static int
+check_argv(struct mdoc *m, const struct mdoc_node *n, 
+		const struct mdoc_argv *v)
+{
+	int		 i;
+
+	for (i = 0; i < (int)v->sz; i++)
+		if ( ! check_text(m, v->line, v->pos, v->value[i]))
+			return(0);
+
+	if (MDOC_Std == v->arg) {
+		/* `Nm' name must be set. */
+		if (v->sz || m->meta.name)
+			return(1);
+		return(nerr(m, n, ENAME));
+	}
+
+	return(1);
+}
+
+
+static int
+check_text(struct mdoc *mdoc, int line, int pos, const char *p)
+{
+	size_t		 c;
+
+	/* FIXME: indicate deprecated escapes \*(xx and \*x. */
+
+	for ( ; *p; p++) {
+		if ('\t' == *p) {
+			if ( ! (MDOC_LITERAL & mdoc->flags))
+				return(perr(mdoc, line, pos, EPRINT));
+		} else if ( ! isprint((u_char)*p))
+			return(perr(mdoc, line, pos, EPRINT));
+
+		if ('\\' != *p)
+			continue;
+
+		c = mdoc_isescape(p);
+		if (c) {
+			p += (int)c - 1;
+			continue;
+		}
+		if ( ! (MDOC_IGN_ESCAPE & mdoc->pflags))
+			return(perr(mdoc, line, pos, EESCAPE));
+		if ( ! pwarn(mdoc, line, pos, WESCAPE))
+			return(0);
+	}
+
+	return(1);
+}
+
+
+
+
+static int
+check_parent(PRE_ARGS, int tok, enum mdoc_type t)
+{
+
+	assert(n->parent);
+	if ((MDOC_ROOT == t || tok == n->parent->tok) &&
+			(t == n->parent->type))
+		return(1);
+
+	return(mdoc_nerr(mdoc, n, "require parent %s",
+		MDOC_ROOT == t ? "<root>" : mdoc_macronames[tok]));
+}
+
+
+
+static int
+pre_display(PRE_ARGS)
+{
+	struct mdoc_node *node;
+
+	/* Display elements (`Bd', `D1'...) cannot be nested. */
+
+	if (MDOC_BLOCK != n->type)
+		return(1);
+
+	/* LINTED */
+	for (node = mdoc->last->parent; node; node = node->parent) 
+		if (MDOC_BLOCK == node->type)
+			if (MDOC_Bd == node->tok)
+				break;
+	if (NULL == node)
+		return(1);
+
+	return(nerr(mdoc, n, ENESTDISP));
+}
+
+
+static int
+pre_bl(PRE_ARGS)
+{
+	int		 i, type, width, offset;
+
+	if (MDOC_BLOCK != n->type)
+		return(1);
+	if (NULL == n->args)
+		return(nerr(mdoc, n, ELISTTYPE));
+
+	/* Make sure that only one type of list is specified.  */
+
+	type = offset = width = -1;
+
+	/* LINTED */
+	for (i = 0; i < (int)n->args->argc; i++)
+		switch (n->args->argv[i].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 (-1 == type) {
+				type = n->args->argv[i].arg;
+				break;
+			}
+			return(nerr(mdoc, n, EMULTILIST));
+		case (MDOC_Width):
+			if (-1 == width) {
+				width = n->args->argv[i].arg;
+				break;
+			}
+			return(nerr(mdoc, n, EARGREP));
+		case (MDOC_Offset):
+			if (-1 == offset) {
+				offset = n->args->argv[i].arg;
+				break;
+			}
+			return(nerr(mdoc, n, EARGREP));
+		default:
+			break;
+		}
+
+	if (-1 == type)
+		return(nerr(mdoc, n, ELISTTYPE));
+
+	switch (type) {
+	case (MDOC_Column):
+		/* FALLTHROUGH */
+	case (MDOC_Diag):
+		/* FALLTHROUGH */
+	case (MDOC_Inset):
+		/* FALLTHROUGH */
+	case (MDOC_Item):
+		if (-1 == width)
+			break;
+		return(mdoc_nwarn(mdoc, n, WARN_SYNTAX,
+				"superfluous %s argument",
+				mdoc_argnames[MDOC_Width]));
+	case (MDOC_Tag):
+		if (-1 != width)
+			break;
+		return(mdoc_nwarn(mdoc, n, WARN_SYNTAX, 
+				"suggest %s argument", 
+				mdoc_argnames[MDOC_Width]));
+	default:
+		break;
+	}
+
+	return(1);
+}
+
+
+static int
+pre_bd(PRE_ARGS)
+{
+	int		 i, type, err;
+
+	if (MDOC_BLOCK != n->type)
+		return(1);
+	if (NULL == n->args) 
+		return(nerr(mdoc, n, EDISPTYPE));
+
+	/* Make sure that only one type of display is specified.  */
+
+	/* LINTED */
+	for (i = 0, err = type = 0; ! err && 
+			i < (int)n->args->argc; i++)
+		switch (n->args->argv[i].arg) {
+		case (MDOC_Ragged):
+			/* FALLTHROUGH */
+		case (MDOC_Unfilled):
+			/* FALLTHROUGH */
+		case (MDOC_Filled):
+			/* FALLTHROUGH */
+		case (MDOC_Literal):
+			/* FALLTHROUGH */
+		case (MDOC_File):
+			if (0 == type++) 
+				break;
+			return(nerr(mdoc, n, EMULTIDISP));
+		default:
+			break;
+		}
+
+	if (type)
+		return(1);
+	return(nerr(mdoc, n, EDISPTYPE));
+}
+
+
+static int
+pre_ss(PRE_ARGS)
+{
+
+	if (MDOC_BLOCK != n->type)
+		return(1);
+	return(check_parent(mdoc, n, MDOC_Sh, MDOC_BODY));
+}
+
+
+static int
+pre_sh(PRE_ARGS)
+{
+
+	if (MDOC_BLOCK != n->type)
+		return(1);
+	return(check_parent(mdoc, n, -1, MDOC_ROOT));
+}
+
+
+static int
+pre_it(PRE_ARGS)
+{
+
+	if (MDOC_BLOCK != n->type)
+		return(1);
+	return(check_parent(mdoc, n, MDOC_Bl, MDOC_BODY));
+}
+
+
+static int
+pre_an(PRE_ARGS)
+{
+
+	if (NULL == n->args || 1 == n->args->argc)
+		return(1);
+	return(mdoc_nerr(mdoc, n, "only one argument allowed"));
+}
+
+
+static int
+pre_lb(PRE_ARGS)
+{
+
+	return(check_sec(mdoc, n, SEC_LIBRARY, SEC_CUSTOM));
+}
+
+
+static int
+pre_rv(PRE_ARGS)
+{
+
+	if ( ! check_msec(mdoc, n, 2, 3, 0))
+		return(0);
+	return(check_stdarg(mdoc, n));
+}
+
+
+static int
+pre_ex(PRE_ARGS)
+{
+
+	if ( ! check_msec(mdoc, n, 1, 6, 8, 0))
+		return(0);
+	return(check_stdarg(mdoc, n));
+}
+
+
+static int
+pre_er(PRE_ARGS)
+{
+
+	return(check_msec(mdoc, n, 2, 0));
+}
+
+
+static int
+pre_cd(PRE_ARGS)
+{
+
+	return(check_msec(mdoc, n, 4, 0));
+}
+
+
+static int
+pre_prologue(PRE_ARGS)
+{
+
+	return(check_sec(mdoc, n, SEC_PROLOGUE, SEC_CUSTOM));
+}
+
+
+static int
+pre_dt(PRE_ARGS)
+{
+
+	if (0 == mdoc->meta.date || mdoc->meta.os)
+		if ( ! nwarn(mdoc, n, WPROLOOO))
+			return(0);
+	if (mdoc->meta.title)
+		if ( ! nwarn(mdoc, n, WPROLREP))
+			return(0);
+	return(1);
+}
+
+
+static int
+pre_os(PRE_ARGS)
+{
+
+	if (NULL == mdoc->meta.title || 0 == mdoc->meta.date)
+		if ( ! nwarn(mdoc, n, WPROLOOO))
+			return(0);
+	if (mdoc->meta.os)
+		if ( ! nwarn(mdoc, n, WPROLREP))
+			return(0);
+	return(1);
+}
+
+
+static int
+pre_dd(PRE_ARGS)
+{
+
+	if (mdoc->meta.title || mdoc->meta.os)
+		if ( ! nwarn(mdoc, n, WPROLOOO))
+			return(0);
+	if (mdoc->meta.date)
+		if ( ! nwarn(mdoc, n, WPROLREP))
+			return(0);
+	return(1);
+}
+
+
+static int
+post_bf(POST_ARGS)
+{
+	char		 *p;
+	struct mdoc_node *head;
+
+	if (MDOC_BLOCK != mdoc->last->type)
+		return(1);
+
+	head = mdoc->last->head;
+
+	if (NULL == mdoc->last->args) {
+		if (NULL == head->child || 
+				MDOC_TEXT != head->child->type)
+			return(mdoc_err(mdoc, "text argument expected"));
+
+		p = head->child->string;
+		if (xstrcmp(p, "Em"))
+			return(1);
+		else if (xstrcmp(p, "Li"))
+			return(1);
+		else if (xstrcmp(p, "Sm"))
+			return(1);
+		return(mdoc_nerr(mdoc, head->child, "invalid font"));
+	}
+
+	if (head->child)
+		return(mdoc_err(mdoc, "one argument expected"));
+
+	return(1);
+}
+
+
+static int
+post_nm(POST_ARGS)
+{
+
+	if (mdoc->last->child)
+		return(1);
+	if (mdoc->meta.name)
+		return(1);
+	return(merr(mdoc, ENAME));
+}
+
+
+static int
+post_at(POST_ARGS)
+{
+
+	if (NULL == mdoc->last->child)
+		return(1);
+	if (MDOC_TEXT != mdoc->last->child->type)
+		return(merr(mdoc, EATT));
+	if (mdoc_a2att(mdoc->last->child->string))
+		return(1);
+	return(merr(mdoc, EATT));
+}
+
+
+static int
+post_an(POST_ARGS)
+{
+
+	if (mdoc->last->args) {
+		if (NULL == mdoc->last->child)
+			return(1);
+		return(merr(mdoc, ELINE));
+	}
+
+	if (mdoc->last->child)
+		return(1);
+	return(merr(mdoc, ELINE));
+}
+
+
+static int
+post_args(POST_ARGS)
+{
+
+	if (mdoc->last->args)
+		return(1);
+	return(merr(mdoc, ELINE));
+}
+
+
+static int
+post_it(POST_ARGS)
+{
+	int		  type, i, cols;
+	struct mdoc_node *n, *c;
+
+	if (MDOC_BLOCK != mdoc->last->type)
+		return(1);
+
+	n = mdoc->last->parent->parent;
+	if (NULL == n->args)
+		return(merr(mdoc, ELISTTYPE));
+
+	/* Some types require block-head, some not. */
+
+	/* LINTED */
+	for (cols = type = -1, i = 0; -1 == type && 
+			i < (int)n->args->argc; i++)
+		switch (n->args->argv[i].arg) {
+		case (MDOC_Tag):
+			/* FALLTHROUGH */
+		case (MDOC_Diag):
+			/* FALLTHROUGH */
+		case (MDOC_Hang):
+			/* FALLTHROUGH */
+		case (MDOC_Ohang):
+			/* FALLTHROUGH */
+		case (MDOC_Inset):
+			/* FALLTHROUGH */
+		case (MDOC_Bullet):
+			/* FALLTHROUGH */
+		case (MDOC_Dash):
+			/* FALLTHROUGH */
+		case (MDOC_Enum):
+			/* FALLTHROUGH */
+		case (MDOC_Hyphen):
+			/* FALLTHROUGH */
+		case (MDOC_Item):
+			type = n->args->argv[i].arg;
+			break;
+		case (MDOC_Column):
+			type = n->args->argv[i].arg;
+			cols = (int)n->args->argv[i].sz;
+			break;
+		default:
+			break;
+		}
+
+	if (-1 == type)
+		return(merr(mdoc, ELISTTYPE));
+
+	switch (type) {
+	case (MDOC_Tag):
+		if (NULL == mdoc->last->head->child)
+			if ( ! mwarn(mdoc, WLINE))
+				return(0);
+		break;
+	case (MDOC_Hang):
+		/* FALLTHROUGH */
+	case (MDOC_Ohang):
+		/* FALLTHROUGH */
+	case (MDOC_Inset):
+		/* FALLTHROUGH */
+	case (MDOC_Diag):
+		if (NULL == mdoc->last->head->child)
+			if ( ! mwarn(mdoc, WLINE))
+				return(0);
+		if (NULL == mdoc->last->body->child)
+			if ( ! mwarn(mdoc, WMULTILINE))
+				return(0);
+		break;
+	case (MDOC_Bullet):
+		/* FALLTHROUGH */
+	case (MDOC_Dash):
+		/* FALLTHROUGH */
+	case (MDOC_Enum):
+		/* FALLTHROUGH */
+	case (MDOC_Hyphen):
+		/* FALLTHROUGH */
+	case (MDOC_Item):
+		if (mdoc->last->head->child)
+			if ( ! mwarn(mdoc, WNOLINE))
+				return(0);
+		if (NULL == mdoc->last->body->child)
+			if ( ! mwarn(mdoc, WMULTILINE))
+				return(0);
+		break;
+	case (MDOC_Column):
+		if (NULL == mdoc->last->head->child)
+			if ( ! mwarn(mdoc, WLINE))
+				return(0);
+		if (mdoc->last->body->child)
+			if ( ! mwarn(mdoc, WNOMULTILINE))
+				return(0);
+		c = mdoc->last->child;
+		for (i = 0; c && MDOC_HEAD == c->type; c = c->next)
+			i++;
+		if (i == cols)
+			break;
+		return(mdoc_err(mdoc, "column mismatch (have "
+					"%d, want %d)", i, cols));
+	default:
+		break;
+	}
+
+	return(1);
+}
+
+
+static int
+post_bl(POST_ARGS)
+{
+	struct mdoc_node	*n;
+
+	if (MDOC_BODY != mdoc->last->type)
+		return(1);
+	if (NULL == mdoc->last->child)
+		return(1);
+
+	/* LINTED */
+	for (n = mdoc->last->child; n; n = n->next) {
+		if (MDOC_BLOCK == n->type) 
+			if (MDOC_It == n->tok)
+				continue;
+		return(mdoc_nerr(mdoc, n, "bad child of parent %s",
+				mdoc_macronames[mdoc->last->tok]));
+	}
+
+	return(1);
+}
+
+
+static int
+ebool(struct mdoc *mdoc)
+{
+	struct mdoc_node *n;
+
+	/* LINTED */
+	for (n = mdoc->last->child; n; n = n->next) {
+		if (MDOC_TEXT != n->type)
+			break;
+		if (xstrcmp(n->string, "on"))
+			continue;
+		if (xstrcmp(n->string, "off"))
+			continue;
+		break;
+	}
+
+	if (NULL == n)
+		return(1);
+	return(nerr(mdoc, n, EBOOL));
+}
+
+
+static int
+post_root(POST_ARGS)
+{
+
+	if (NULL == mdoc->first->child)
+		return(merr(mdoc, ENODATA));
+	if (SEC_PROLOGUE == mdoc->lastnamed)
+		return(merr(mdoc, ENOPROLOGUE));
+
+	if (MDOC_BLOCK != mdoc->first->child->type)
+		return(merr(mdoc, ENODATA));
+	if (MDOC_Sh != mdoc->first->child->tok)
+		return(merr(mdoc, ENODATA));
+
+	return(1);
+}
+
+
+static int
+post_st(POST_ARGS)
+{
+
+	if (mdoc_a2st(mdoc->last->child->string))
+		return(1);
+	return(mwarn(mdoc, WBADSTAND));
+}
+
+
+static int
+post_sh(POST_ARGS)
+{
+
+	if (MDOC_HEAD == mdoc->last->type)
+		return(post_sh_head(mdoc));
+	if (MDOC_BODY == mdoc->last->type)
+		return(post_sh_body(mdoc));
+
+	return(1);
+}
+
+
+static int
+post_sh_body(POST_ARGS)
+{
+	struct mdoc_node *n;
+
+	if (SEC_NAME != mdoc->lastnamed)
+		return(1);
+
+	/*
+	 * Warn if the NAME section doesn't contain the `Nm' and `Nd'
+	 * macros (can have multiple `Nm' and one `Nd').  Note that the
+	 * children of the BODY declaration can also be "text".
+	 */
+
+	if (NULL == (n = mdoc->last->child))
+		return(mwarn(mdoc, WNAMESECINC));
+
+	for ( ; n && n->next; n = n->next) {
+		if (MDOC_ELEM == n->type && MDOC_Nm == n->tok)
+			continue;
+		if (MDOC_TEXT == n->type)
+			continue;
+		if ( ! mwarn(mdoc, WNAMESECINC))
+			return(0);
+	}
+
+	if (MDOC_ELEM == n->type && MDOC_Nd == n->tok)
+		return(1);
+	return(mwarn(mdoc, WNAMESECINC));
+}
+
+
+static int
+post_sh_head(POST_ARGS)
+{
+	char		  buf[64];
+	enum mdoc_sec	  sec;
+
+	/*
+	 * Process a new section.  Sections are either "named" or
+	 * "custom"; custom sections are user-defined, while named ones
+	 * usually follow a conventional order and may only appear in
+	 * certain manual sections.
+	 */
+
+	assert(MDOC_Sh == mdoc->last->tok);
+
+	(void)xstrlcpys(buf, mdoc->last->child, sizeof(buf));
+
+	sec = mdoc_atosec(buf);
+
+	/* The NAME section should always be first. */
+
+	if (SEC_BODY == mdoc->lastnamed && SEC_NAME != sec)
+		return(mwarn(mdoc, WSECOOO));
+	if (SEC_CUSTOM == sec)
+		return(1);
+
+	/* Check for repeated or out-of-order sections. */
+
+	if (sec == mdoc->lastnamed)
+		return(mwarn(mdoc, WSECREP));
+	if (sec < mdoc->lastnamed)
+		return(mwarn(mdoc, WSECOOO));
+
+	/* Check particular section/manual section conventions. */
+
+	switch (sec) {
+	case (SEC_LIBRARY):
+		switch (mdoc->meta.msec) {
+		case (2):
+			/* FALLTHROUGH */
+		case (3):
+			break;
+		default:
+			return(mwarn(mdoc, WWRONGMSEC));
+		}
+		break;
+	default:
+		break;
+	}
+
+	return(1);
+}
+
+
+static int
+pre_fd(PRE_ARGS)
+{
+
+	return(check_sec(mdoc, n, SEC_SYNOPSIS, SEC_CUSTOM));
+}