Return to mdoc_macro.c CVS log

Up to [local] / src / usr.bin / mandoc

Support .It .Xo.
The trick is to not switch from the .It header to the body at EOL, but,
in case an explicit block macro follows, at the end of the block.

/*	$Id: mdoc_macro.c,v 1.29 2010/02/26 12:12:24 schwarze Exp $ */
/*
 * Copyright (c) 2008, 2009 Kristaps Dzonsons <kristaps@kth.se>
 *
 * 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 <assert.h>
#include <ctype.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <time.h>

#include "libmdoc.h"

#define	REWIND_REWIND	(1 << 0)
#define	REWIND_NOHALT	(1 << 1)
#define	REWIND_HALT	(1 << 2)

static	int	  ctx_synopsis(MACRO_PROT_ARGS);
static	int	  obsolete(MACRO_PROT_ARGS);
static	int	  blk_part_exp(MACRO_PROT_ARGS);
static	int	  in_line_eoln(MACRO_PROT_ARGS);
static	int	  in_line_argn(MACRO_PROT_ARGS);
static	int	  in_line(MACRO_PROT_ARGS);
static	int	  blk_full(MACRO_PROT_ARGS);
static	int	  blk_exp_close(MACRO_PROT_ARGS);
static	int	  blk_part_imp(MACRO_PROT_ARGS);

static	int	  phrase(struct mdoc *, int, int, char *);
static	int	  rew_dohalt(int, enum mdoc_type, 
			const struct mdoc_node *);
static	int	  rew_alt(int);
static	int	  rew_dobreak(int, const struct mdoc_node *);
static	int	  rew_elem(struct mdoc *, int);
static	int	  rew_sub(enum mdoc_type, struct mdoc *, 
			int, int, int);
static	int	  rew_last(struct mdoc *, 
			const struct mdoc_node *);
static	int	  append_delims(struct mdoc *, int, int *, char *);
static	int	  lookup(int, const char *);
static	int	  lookup_raw(const char *);
static	int	  swarn(struct mdoc *, enum mdoc_type, int, int, 
			const struct mdoc_node *);

/* Central table of library: who gets parsed how. */

const	struct mdoc_macro __mdoc_macros[MDOC_MAX] = {
	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Ap */
	{ in_line_eoln, MDOC_PROLOGUE }, /* Dd */
	{ in_line_eoln, MDOC_PROLOGUE }, /* Dt */
	{ in_line_eoln, MDOC_PROLOGUE }, /* Os */
	{ blk_full, 0 }, /* Sh */
	{ blk_full, 0 }, /* Ss */ 
	{ in_line_eoln, 0 }, /* Pp */ 
	{ blk_part_imp, MDOC_PARSED }, /* D1 */
	{ blk_part_imp, MDOC_PARSED }, /* Dl */
	{ blk_full, MDOC_EXPLICIT }, /* Bd */
	{ blk_exp_close, MDOC_EXPLICIT }, /* Ed */
	{ blk_full, MDOC_EXPLICIT }, /* Bl */
	{ blk_exp_close, MDOC_EXPLICIT }, /* El */
	{ blk_full, MDOC_PARSED }, /* It */
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Ad */ 
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* An */
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Ar */
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Cd */
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Cm */
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Dv */ 
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Er */ 
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Ev */ 
	{ in_line_eoln, 0 }, /* Ex */
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Fa */ 
	{ in_line_eoln, 0 }, /* Fd */ 
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Fl */
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Fn */ 
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Ft */ 
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Ic */ 
	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* In */
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Li */
	{ blk_full, 0 }, /* Nd */ 
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Nm */ 
	{ blk_part_imp, MDOC_CALLABLE | MDOC_PARSED }, /* Op */
	{ obsolete, 0 }, /* Ot */
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Pa */
	{ in_line_eoln, 0 }, /* Rv */
	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* St */ 
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Va */
	{ ctx_synopsis, MDOC_CALLABLE | MDOC_PARSED }, /* Vt */ 
	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Xr */
	{ in_line_eoln, 0 }, /* %A */
	{ in_line_eoln, 0 }, /* %B */
	{ in_line_eoln, 0 }, /* %D */
	{ in_line_eoln, 0 }, /* %I */
	{ in_line_eoln, 0 }, /* %J */
	{ in_line_eoln, 0 }, /* %N */
	{ in_line_eoln, 0 }, /* %O */
	{ in_line_eoln, 0 }, /* %P */
	{ in_line_eoln, 0 }, /* %R */
	{ in_line_eoln, 0 }, /* %T */
	{ in_line_eoln, 0 }, /* %V */
	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Ac */
	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* Ao */
	{ blk_part_imp, MDOC_CALLABLE | MDOC_PARSED }, /* Aq */
	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* At */
	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Bc */
	{ blk_full, MDOC_EXPLICIT }, /* Bf */ 
	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* Bo */
	{ blk_part_imp, MDOC_CALLABLE | MDOC_PARSED }, /* Bq */
	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Bsx */
	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Bx */
	{ in_line_eoln, 0 }, /* Db */
	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Dc */
	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* Do */
	{ blk_part_imp, MDOC_CALLABLE | MDOC_PARSED }, /* Dq */
	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Ec */
	{ blk_exp_close, MDOC_EXPLICIT }, /* Ef */
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Em */ 
	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* Eo */
	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Fx */
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Ms */
	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* No */
	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Ns */
	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Nx */
	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Ox */
	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Pc */
	{ in_line_argn, MDOC_PARSED | MDOC_IGNDELIM }, /* Pf */
	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* Po */
	{ blk_part_imp, MDOC_CALLABLE | MDOC_PARSED }, /* Pq */
	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Qc */
	{ blk_part_imp, MDOC_CALLABLE | MDOC_PARSED }, /* Ql */
	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* Qo */
	{ blk_part_imp, MDOC_CALLABLE | MDOC_PARSED }, /* Qq */
	{ blk_exp_close, MDOC_EXPLICIT }, /* Re */
	{ blk_full, MDOC_EXPLICIT }, /* Rs */
	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Sc */
	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* So */
	{ blk_part_imp, MDOC_CALLABLE | MDOC_PARSED }, /* Sq */
	{ in_line_eoln, 0 }, /* Sm */
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Sx */
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Sy */
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Tn */
	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Ux */
	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Xc */
	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* Xo */
	{ blk_full, MDOC_EXPLICIT | MDOC_CALLABLE }, /* Fo */ 
	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Fc */ 
	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* Oo */
	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Oc */
	{ blk_full, MDOC_EXPLICIT }, /* Bk */
	{ blk_exp_close, MDOC_EXPLICIT }, /* Ek */
	{ in_line_eoln, 0 }, /* Bt */
	{ in_line_eoln, 0 }, /* Hf */
	{ obsolete, 0 }, /* Fr */
	{ in_line_eoln, 0 }, /* Ud */
	{ in_line_eoln, 0 }, /* Lb */
	{ in_line_eoln, 0 }, /* Lp */ 
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Lk */ 
	{ in_line, MDOC_CALLABLE | MDOC_PARSED }, /* Mt */ 
	{ blk_part_imp, MDOC_CALLABLE | MDOC_PARSED }, /* Brq */
	{ blk_part_exp, MDOC_CALLABLE | MDOC_PARSED | MDOC_EXPLICIT }, /* Bro */
	{ blk_exp_close, MDOC_EXPLICIT | MDOC_CALLABLE | MDOC_PARSED }, /* Brc */
	{ in_line_eoln, 0 }, /* %C */
	{ obsolete, 0 }, /* Es */
	{ obsolete, 0 }, /* En */
	{ in_line_argn, MDOC_CALLABLE | MDOC_PARSED }, /* Dx */
	{ in_line_eoln, 0 }, /* %Q */
	{ in_line_eoln, 0 }, /* br */
	{ in_line_eoln, 0 }, /* sp */
	{ in_line_eoln, 0 }, /* %U */
};

const	struct mdoc_macro * const mdoc_macros = __mdoc_macros;


static int
swarn(struct mdoc *mdoc, enum mdoc_type type, 
		int line, int pos, const struct mdoc_node *p)
{
	const char	*n, *t, *tt;

	n = t = "<root>";
	tt = "block";

	switch (type) {
	case (MDOC_BODY):
		tt = "multi-line";
		break;
	case (MDOC_HEAD):
		tt = "line";
		break;
	default:
		break;
	}

	switch (p->type) {
	case (MDOC_BLOCK):
		n = mdoc_macronames[p->tok];
		t = "block";
		break;
	case (MDOC_BODY):
		n = mdoc_macronames[p->tok];
		t = "multi-line";
		break;
	case (MDOC_HEAD):
		n = mdoc_macronames[p->tok];
		t = "line";
		break;
	default:
		break;
	}

	if ( ! (MDOC_IGN_SCOPE & mdoc->pflags))
		return(mdoc_verr(mdoc, line, pos, 
				"%s scope breaks %s scope of %s", 
				tt, t, n));
	return(mdoc_vwarn(mdoc, line, pos, 
				"%s scope breaks %s scope of %s", 
				tt, t, n));
}


/*
 * This is called at the end of parsing.  It must traverse up the tree,
 * closing out open [implicit] scopes.  Obviously, open explicit scopes
 * are errors.
 */
int
mdoc_macroend(struct mdoc *m)
{
	struct mdoc_node *n;

	/* Scan for open explicit scopes. */

	n = MDOC_VALID & m->last->flags ?  m->last->parent : m->last;

	for ( ; n; n = n->parent) {
		if (MDOC_BLOCK != n->type)
			continue;
		if ( ! (MDOC_EXPLICIT & mdoc_macros[n->tok].flags))
			continue;
		return(mdoc_nerr(m, n, EOPEN));
	}

	/* Rewind to the first. */

	return(rew_last(m, m->first));
}


/*
 * Look up a macro from within a subsequent context.
 */
static int
lookup(int from, const char *p)
{
	/* FIXME: make -diag lists be un-PARSED. */

	if ( ! (MDOC_PARSED & mdoc_macros[from].flags))
		return(MDOC_MAX);
	return(lookup_raw(p));
}


/*
 * Lookup a macro following the initial line macro.
 */
static int
lookup_raw(const char *p)
{
	int		 res;

	if (MDOC_MAX == (res = mdoc_hash_find(p)))
		return(MDOC_MAX);
	if (MDOC_CALLABLE & mdoc_macros[res].flags)
		return(res);
	return(MDOC_MAX);
}


static int
rew_last(struct mdoc *mdoc, const struct mdoc_node *to)
{

	assert(to);
	mdoc->next = MDOC_NEXT_SIBLING;

	/* LINTED */
	while (mdoc->last != to) {
		if ( ! mdoc_valid_post(mdoc))
			return(0);
		if ( ! mdoc_action_post(mdoc))
			return(0);
		mdoc->last = mdoc->last->parent;
		assert(mdoc->last);
	}

	if ( ! mdoc_valid_post(mdoc))
		return(0);
	return(mdoc_action_post(mdoc));
}


/*
 * Return the opening macro of a closing one, e.g., `Ec' has `Eo' as its
 * matching pair.
 */
static int
rew_alt(int tok)
{
	switch (tok) {
	case (MDOC_Ac):
		return(MDOC_Ao);
	case (MDOC_Bc):
		return(MDOC_Bo);
	case (MDOC_Brc):
		return(MDOC_Bro);
	case (MDOC_Dc):
		return(MDOC_Do);
	case (MDOC_Ec):
		return(MDOC_Eo);
	case (MDOC_Ed):
		return(MDOC_Bd);
	case (MDOC_Ef):
		return(MDOC_Bf);
	case (MDOC_Ek):
		return(MDOC_Bk);
	case (MDOC_El):
		return(MDOC_Bl);
	case (MDOC_Fc):
		return(MDOC_Fo);
	case (MDOC_Oc):
		return(MDOC_Oo);
	case (MDOC_Pc):
		return(MDOC_Po);
	case (MDOC_Qc):
		return(MDOC_Qo);
	case (MDOC_Re):
		return(MDOC_Rs);
	case (MDOC_Sc):
		return(MDOC_So);
	case (MDOC_Xc):
		return(MDOC_Xo);
	default:
		break;
	}
	abort();
	/* NOTREACHED */
}


/* 
 * Rewind rules.  This indicates whether to stop rewinding
 * (REWIND_HALT) without touching our current scope, stop rewinding and
 * close our current scope (REWIND_REWIND), or continue (REWIND_NOHALT).
 * The scope-closing and so on occurs in the various rew_* routines.
 */
static int 
rew_dohalt(int tok, enum mdoc_type type, const struct mdoc_node *p)
{

	if (MDOC_ROOT == p->type)
		return(REWIND_HALT);
	if (MDOC_VALID & p->flags)
		return(REWIND_NOHALT);

	switch (tok) {
	case (MDOC_Aq):
		/* FALLTHROUGH */
	case (MDOC_Bq):
		/* FALLTHROUGH */
	case (MDOC_Brq):
		/* FALLTHROUGH */
	case (MDOC_D1):
		/* FALLTHROUGH */
	case (MDOC_Dl):
		/* FALLTHROUGH */
	case (MDOC_Dq):
		/* FALLTHROUGH */
	case (MDOC_Op):
		/* FALLTHROUGH */
	case (MDOC_Pq):
		/* FALLTHROUGH */
	case (MDOC_Ql):
		/* FALLTHROUGH */
	case (MDOC_Qq):
		/* FALLTHROUGH */
	case (MDOC_Sq):
		/* FALLTHROUGH */
	case (MDOC_Vt):
		assert(MDOC_TAIL != type);
		if (type == p->type && tok == p->tok)
			return(REWIND_REWIND);
		break;
	case (MDOC_It):
		assert(MDOC_TAIL != type);
		if (type == p->type && tok == p->tok)
			return(REWIND_REWIND);
		if (MDOC_BODY == p->type && MDOC_Bl == p->tok)
			return(REWIND_HALT);
		break;
	case (MDOC_Sh):
		if (type == p->type && tok == p->tok)
			return(REWIND_REWIND);
		break;
	case (MDOC_Nd):
		/* FALLTHROUGH */
	case (MDOC_Ss):
		assert(MDOC_TAIL != type);
		if (type == p->type && tok == p->tok)
			return(REWIND_REWIND);
		if (MDOC_BODY == p->type && MDOC_Sh == p->tok)
			return(REWIND_HALT);
		break;
	case (MDOC_Ao):
		/* FALLTHROUGH */
	case (MDOC_Bd):
		/* FALLTHROUGH */
	case (MDOC_Bf):
		/* FALLTHROUGH */
	case (MDOC_Bk):
		/* FALLTHROUGH */
	case (MDOC_Bl):
		/* FALLTHROUGH */
	case (MDOC_Bo):
		/* FALLTHROUGH */
	case (MDOC_Bro):
		/* FALLTHROUGH */
	case (MDOC_Do):
		/* FALLTHROUGH */
	case (MDOC_Eo):
		/* FALLTHROUGH */
	case (MDOC_Fo):
		/* FALLTHROUGH */
	case (MDOC_Oo):
		/* FALLTHROUGH */
	case (MDOC_Po):
		/* FALLTHROUGH */
	case (MDOC_Qo):
		/* FALLTHROUGH */
	case (MDOC_Rs):
		/* FALLTHROUGH */
	case (MDOC_So):
		/* FALLTHROUGH */
	case (MDOC_Xo):
		if (type == p->type && tok == p->tok)
			return(REWIND_REWIND);
		break;
	/* Multi-line explicit scope close. */
	case (MDOC_Ac):
		/* FALLTHROUGH */
	case (MDOC_Bc):
		/* FALLTHROUGH */
	case (MDOC_Brc):
		/* FALLTHROUGH */
	case (MDOC_Dc):
		/* FALLTHROUGH */
	case (MDOC_Ec):
		/* FALLTHROUGH */
	case (MDOC_Ed):
		/* FALLTHROUGH */
	case (MDOC_Ek):
		/* FALLTHROUGH */
	case (MDOC_El):
		/* FALLTHROUGH */
	case (MDOC_Fc):
		/* FALLTHROUGH */
	case (MDOC_Ef):
		/* FALLTHROUGH */
	case (MDOC_Oc):
		/* FALLTHROUGH */
	case (MDOC_Pc):
		/* FALLTHROUGH */
	case (MDOC_Qc):
		/* FALLTHROUGH */
	case (MDOC_Re):
		/* FALLTHROUGH */
	case (MDOC_Sc):
		/* FALLTHROUGH */
	case (MDOC_Xc):
		if (type == p->type && rew_alt(tok) == p->tok)
			return(REWIND_REWIND);
		break;
	default:
		abort();
		/* NOTREACHED */
	}

	return(REWIND_NOHALT);
}


/*
 * See if we can break an encountered scope (the rew_dohalt has returned
 * REWIND_NOHALT). 
 */
static int
rew_dobreak(int tok, const struct mdoc_node *p)
{

	assert(MDOC_ROOT != p->type);
	if (MDOC_ELEM == p->type)
		return(1);
	if (MDOC_TEXT == p->type)
		return(1);
	if (MDOC_VALID & p->flags)
		return(1);

	switch (tok) {
	case (MDOC_It):
		return(MDOC_It == p->tok);
	case (MDOC_Nd):
		return(MDOC_Nd == p->tok);
	case (MDOC_Ss):
		return(MDOC_Ss == p->tok);
	case (MDOC_Sh):
		if (MDOC_Nd == p->tok)
			return(1);
		if (MDOC_Ss == p->tok)
			return(1);
		return(MDOC_Sh == p->tok);
	case (MDOC_El):
		if (MDOC_It == p->tok)
			return(1);
		break;
	case (MDOC_Oc):
		/* XXX - experimental! */
		if (MDOC_Op == p->tok)
			return(1);
		break;
	default:
		break;
	}

	if (MDOC_EXPLICIT & mdoc_macros[tok].flags) 
		return(p->tok == rew_alt(tok));
	else if (MDOC_BLOCK == p->type)
		return(1);

	return(tok == p->tok);
}


static int
rew_elem(struct mdoc *mdoc, int tok)
{
	struct mdoc_node *n;

	n = mdoc->last;
	if (MDOC_ELEM != n->type)
		n = n->parent;
	assert(MDOC_ELEM == n->type);
	assert(tok == n->tok);

	return(rew_last(mdoc, n));
}


static int
rew_sub(enum mdoc_type t, struct mdoc *m, 
		int tok, int line, int ppos)
{
	struct mdoc_node *n;
	int		  c;

	/* LINTED */
	for (n = m->last; n; n = n->parent) {
		c = rew_dohalt(tok, t, n);
		if (REWIND_HALT == c) {
			if (MDOC_BLOCK != t)
				return(1);
			if ( ! (MDOC_EXPLICIT & mdoc_macros[tok].flags))
				return(1);
			return(mdoc_perr(m, line, ppos, ENOCTX));
		}
		if (REWIND_REWIND == c)
			break;
		else if (rew_dobreak(tok, n))
			continue;
		if ( ! swarn(m, t, line, ppos, n))
			return(0);
	}

	assert(n);
	if ( ! rew_last(m, n))
		return(0);

	/*
	 * The current block extends an enclosing block beyond a line break.
	 * Now that the current block ends, close the enclosing block, too.
	 */
	if ((n = n->pending) != NULL) {
		assert(MDOC_HEAD == n->type);
		if ( ! rew_last(m, n))
			return(0);
		if ( ! mdoc_body_alloc(m, n->line, n->pos, n->tok))
			return(0);
	}
	return(1);
}


static int
append_delims(struct mdoc *mdoc, int line, int *pos, char *buf)
{
	int		 c, lastarg;
	char		*p;

	if (0 == buf[*pos])
		return(1);

	for (;;) {
		lastarg = *pos;
		c = mdoc_zargs(mdoc, line, pos, buf, ARGS_NOWARN, &p);
		assert(ARGS_PHRASE != c);

		if (ARGS_ERROR == c)
			return(0);
		else if (ARGS_EOLN == c)
			break;
		assert(mdoc_isdelim(p));
		if ( ! mdoc_word_alloc(mdoc, line, lastarg, p))
			return(0);
	}

	return(1);
}


/*
 * Close out block partial/full explicit.  
 */
static int
blk_exp_close(MACRO_PROT_ARGS)
{
	int	 	 j, c, lastarg, maxargs, flushed;
	char		*p;

	switch (tok) {
	case (MDOC_Ec):
		maxargs = 1;
		break;
	default:
		maxargs = 0;
		break;
	}

	if ( ! (MDOC_CALLABLE & mdoc_macros[tok].flags)) {
		if (buf[*pos]) 
			if ( ! mdoc_pwarn(m, line, ppos, ENOLINE))
				return(0);

		if ( ! rew_sub(MDOC_BODY, m, tok, line, ppos))
			return(0);
		return(rew_sub(MDOC_BLOCK, m, tok, line, ppos));
	}

	if ( ! rew_sub(MDOC_BODY, m, tok, line, ppos))
		return(0);

	if (maxargs > 0) 
		if ( ! mdoc_tail_alloc(m, line, ppos, rew_alt(tok)))
			return(0);

	for (flushed = j = 0; ; j++) {
		lastarg = *pos;

		if (j == maxargs && ! flushed) {
			if ( ! rew_sub(MDOC_BLOCK, m, tok, line, ppos))
				return(0);
			flushed = 1;
		}

		c = mdoc_args(m, line, pos, buf, tok, &p);

		if (ARGS_ERROR == c)
			return(0);
		if (ARGS_PUNCT == c)
			break;
		if (ARGS_EOLN == c)
			break;

		if (MDOC_MAX != (c = lookup(tok, p))) {
			if ( ! flushed) {
				if ( ! rew_sub(MDOC_BLOCK, m, tok, line, ppos))
					return(0);
				flushed = 1;
			}
			if ( ! mdoc_macro(m, c, line, lastarg, pos, buf))
				return(0);
			break;
		} 

		if ( ! mdoc_word_alloc(m, line, lastarg, p))
			return(0);
	}

	if ( ! flushed && ! rew_sub(MDOC_BLOCK, m, tok, line, ppos))
		return(0);

	if (ppos > 1)
		return(1);
	return(append_delims(m, line, pos, buf));
}


static int
in_line(MACRO_PROT_ARGS)
{
	int		  la, lastpunct, c, w, cnt, d, nc;
	struct mdoc_arg	 *arg;
	char		 *p;

	/*
	 * Whether we allow ignored elements (those without content,
	 * usually because of reserved words) to squeak by.
	 */
	switch (tok) {
	case (MDOC_An):
		/* FALLTHROUGH */
	case (MDOC_Ar):
		/* FALLTHROUGH */
	case (MDOC_Fl):
		/* FALLTHROUGH */
	case (MDOC_Lk):
		/* FALLTHROUGH */
	case (MDOC_Nm):
		/* FALLTHROUGH */
	case (MDOC_Pa):
		nc = 1;
		break;
	default:
		nc = 0;
		break;
	}

	for (arg = NULL;; ) {
		la = *pos;
		c = mdoc_argv(m, line, tok, &arg, pos, buf);

		if (ARGV_WORD == c) {
			*pos = la;
			break;
		} 
		if (ARGV_EOLN == c)
			break;
		if (ARGV_ARG == c)
			continue;

		mdoc_argv_free(arg);
		return(0);
	}

	for (cnt = 0, lastpunct = 1;; ) {
		la = *pos;
		w = mdoc_args(m, line, pos, buf, tok, &p);

		if (ARGS_ERROR == w)
			return(0);
		if (ARGS_EOLN == w)
			break;
		if (ARGS_PUNCT == w)
			break;

		/* Quoted words shouldn't be looked-up. */

		c = ARGS_QWORD == w ? MDOC_MAX : lookup(tok, p);

		/* 
		 * In this case, we've located a submacro and must
		 * execute it.  Close out scope, if open.  If no
		 * elements have been generated, either create one (nc)
		 * or raise a warning.
		 */

		if (MDOC_MAX != c) {
			if (0 == lastpunct && ! rew_elem(m, tok))
				return(0);
			if (nc && 0 == cnt) {
				if ( ! mdoc_elem_alloc(m, line, ppos, tok, arg))
					return(0);
				if ( ! rew_last(m, m->last))
					return(0);
			} else if ( ! nc && 0 == cnt) {
				mdoc_argv_free(arg);
				if ( ! mdoc_pwarn(m, line, ppos, EIGNE))
					return(0);
			}
			c = mdoc_macro(m, c, line, la, pos, buf);
			if (0 == c)
				return(0);
			if (ppos > 1)
				return(1);
			return(append_delims(m, line, pos, buf));
		} 

		/* 
		 * Non-quote-enclosed punctuation.  Set up our scope, if
		 * a word; rewind the scope, if a delimiter; then append
		 * the word. 
		 */

		d = mdoc_isdelim(p);

		if (ARGS_QWORD != w && d) {
			if (0 == lastpunct && ! rew_elem(m, tok))
				return(0);
			lastpunct = 1;
		} else if (lastpunct) {
			if ( ! mdoc_elem_alloc(m, line, ppos, tok, arg))
				return(0);
			lastpunct = 0;
		}

		if ( ! d)
			cnt++;
		if ( ! mdoc_word_alloc(m, line, la, p))
			return(0);

		/*
		 * `Fl' macros have their scope re-opened with each new
		 * word so that the `-' can be added to each one without
		 * having to parse out spaces.
		 */
		if (0 == lastpunct && MDOC_Fl == tok) {
			if ( ! rew_elem(m, tok))
				return(0);
			lastpunct = 1;
		}
	}

	if (0 == lastpunct && ! rew_elem(m, tok))
		return(0);

	/*
	 * If no elements have been collected and we're allowed to have
	 * empties (nc), open a scope and close it out.  Otherwise,
	 * raise a warning.
	 *
	 */
	if (nc && 0 == cnt) {
		if ( ! mdoc_elem_alloc(m, line, ppos, tok, arg))
			return(0);
		if ( ! rew_last(m, m->last))
			return(0);
	} else if ( ! nc && 0 == cnt) {
		mdoc_argv_free(arg);
		if ( ! mdoc_pwarn(m, line, ppos, EIGNE))
			return(0);
	}

	if (ppos > 1)
		return(1);
	return(append_delims(m, line, pos, buf));
}


static int
blk_full(MACRO_PROT_ARGS)
{
	int		  c, lastarg, reopen, dohead;
	struct mdoc_arg	 *arg;
	struct mdoc_node *head, *n;
	char		 *p;

	/* 
	 * Whether to process a block-head section.  If this is
	 * non-zero, then a head will be opened for all line arguments.
	 * If not, then the head will always be empty and only a body
	 * will be opened, which will stay open at the eoln.
	 */

	switch (tok) {
	case (MDOC_Nd):
		dohead = 0;
		break;
	default:
		dohead = 1;
		break;
	}

	if ( ! (MDOC_EXPLICIT & mdoc_macros[tok].flags)) {
		if ( ! rew_sub(MDOC_BODY, m, tok, line, ppos))
			return(0);
		if ( ! rew_sub(MDOC_BLOCK, m, tok, line, ppos))
			return(0);
	}

	for (arg = NULL;; ) {
		lastarg = *pos;
		c = mdoc_argv(m, line, tok, &arg, pos, buf);

		if (ARGV_WORD == c) {
			*pos = lastarg;
			break;
		} 

		if (ARGV_EOLN == c)
			break;
		if (ARGV_ARG == c)
			continue;

		mdoc_argv_free(arg);
		return(0);
	}

	if ( ! mdoc_block_alloc(m, line, ppos, tok, arg))
		return(0);
	if ( ! mdoc_head_alloc(m, line, ppos, tok))
		return(0);
	head = m->last;

	if (0 == buf[*pos]) {
		if ( ! rew_sub(MDOC_HEAD, m, tok, line, ppos))
			return(0);
		if ( ! mdoc_body_alloc(m, line, ppos, tok))
			return(0);
		return(1);
	}

	/* Immediately close out head and enter body, if applicable. */

	if (0 == dohead) {
		if ( ! rew_sub(MDOC_HEAD, m, tok, line, ppos))
			return(0);
		if ( ! mdoc_body_alloc(m, line, ppos, tok))
			return(0);
	} 

	for (reopen = 0;; ) {
		lastarg = *pos;
		c = mdoc_args(m, line, pos, buf, tok, &p);

		if (ARGS_ERROR == c)
			return(0);
		if (ARGS_EOLN == c)
			break;
		if (ARGS_PHRASE == c) {
			assert(dohead);
			if (reopen && ! mdoc_head_alloc(m, line, ppos, tok))
				return(0);
			head = m->last;
			/*
			 * Phrases are self-contained macro phrases used
			 * in the columnar output of a macro. They need
			 * special handling.
			 */
			if ( ! phrase(m, line, lastarg, buf))
				return(0);
			if ( ! rew_sub(MDOC_HEAD, m, tok, line, ppos))
				return(0);

			reopen = 1;
			continue;
		}

		if (MDOC_MAX == (c = lookup(tok, p))) {
			if ( ! mdoc_word_alloc(m, line, lastarg, p))
				return(0);
			continue;
		} 

		if ( ! mdoc_macro(m, c, line, lastarg, pos, buf))
			return(0);
		break;
	}
	
	if (1 == ppos && ! append_delims(m, line, pos, buf))
		return(0);

	/* If the body's already open, then just return. */
	if (0 == dohead) 
		return(1);

	/*
	 * If there is an open sub-block requiring explicit close-out,
	 * postpone switching the current block from head to body
	 * until the rew_sub() call closing out that sub-block.
	 */
	for (n = m->last; n && n != head; n = n->parent) {
		if (MDOC_BLOCK == n->type &&
		    MDOC_EXPLICIT & mdoc_macros[n->tok].flags) {
			n->pending = head;
			return(1);
		}
	}

	if ( ! rew_sub(MDOC_HEAD, m, tok, line, ppos))
		return(0);
	if ( ! mdoc_body_alloc(m, line, ppos, tok))
		return(0);

	return(1);
}


static int
blk_part_imp(MACRO_PROT_ARGS)
{
	int		  la, c;
	char		 *p;
	struct mdoc_node *blk, *body, *n;

	/* If applicable, close out prior scopes. */

	if ( ! mdoc_block_alloc(m, line, ppos, tok, NULL))
		return(0);
	/* Saved for later close-out. */
	blk = m->last;
	if ( ! mdoc_head_alloc(m, line, ppos, tok))
		return(0);
	if ( ! rew_sub(MDOC_HEAD, m, tok, line, ppos))
		return(0);
	if ( ! mdoc_body_alloc(m, line, ppos, tok))
		return(0);
	/* Saved for later close-out. */
	body = m->last;

	/* Body argument processing. */

	for (;;) {
		la = *pos;
		c = mdoc_args(m, line, pos, buf, tok, &p);
		assert(ARGS_PHRASE != c);

		if (ARGS_ERROR == c)
			return(0);
		if (ARGS_PUNCT == c)
			break;
		if (ARGS_EOLN == c)
			break;

		if (MDOC_MAX == (c = lookup(tok, p))) {
			if ( ! mdoc_word_alloc(m, line, la, p))
				return(0);
			continue;
		} 

		if ( ! mdoc_macro(m, c, line, la, pos, buf))
			return(0);
		break;
	}

	/* 
	 * If we can't rewind to our body, then our scope has already
	 * been closed by another macro (like `Oc' closing `Op').  This
	 * is ugly behaviour nodding its head to OpenBSD's overwhelming
	 * crufty use of `Op' breakage--XXX, deprecate in time.
	 */
	for (n = m->last; n; n = n->parent)
		if (body == n)
			break;
	if (NULL == n && ! mdoc_nwarn(m, body, EIMPBRK))
		return(0);
	if (n && ! rew_last(m, body))
		return(0);

	/* Standard appending of delimiters. */

	if (1 == ppos && ! append_delims(m, line, pos, buf))
		return(0);

	/* Rewind scope, if applicable. */

	if (n && ! rew_last(m, blk))
		return(0);

	return(1);
}


static int
blk_part_exp(MACRO_PROT_ARGS)
{
	int		  la, flushed, j, c, maxargs;
	char		 *p;

	/* Number of head arguments.  Only `Eo' has these, */

	switch (tok) {
	case (MDOC_Eo):
		maxargs = 1;
		break;
	default:
		maxargs = 0;
		break;
	}

	/* Begin the block scope. */

	if ( ! mdoc_block_alloc(m, line, ppos, tok, NULL))
		return(0); 

	/* 
	 * If no head arguments, open and then close out a head, noting
	 * that we've flushed our terms.  `flushed' means that we've
	 * flushed out the head and the body is open.
	 */

	if (0 == maxargs) {
		if ( ! mdoc_head_alloc(m, line, ppos, tok))
			return(0);
		if ( ! rew_sub(MDOC_HEAD, m, tok, line, ppos))
			return(0);
		if ( ! mdoc_body_alloc(m, line, ppos, tok))
			return(0);
		flushed = 1;
	} else {
		if ( ! mdoc_head_alloc(m, line, ppos, tok))
			return(0);
		flushed = 0;
	}

	/* Process the head/head+body line arguments. */

	for (j = 0; ; j++) {
		la = *pos;
		if (j == maxargs && ! flushed) {
			if ( ! rew_sub(MDOC_HEAD, m, tok, line, ppos))
				return(0);
			flushed = 1;
			if ( ! mdoc_body_alloc(m, line, ppos, tok))
				return(0);
		}

		c = mdoc_args(m, line, pos, buf, tok, &p);
		assert(ARGS_PHRASE != c);

		if (ARGS_ERROR == c)
			return(0);
		if (ARGS_PUNCT == c)
			break;
		if (ARGS_EOLN == c)
			break;

		if (MDOC_MAX != (c = lookup(tok, p))) {
			if ( ! flushed) {
				if ( ! rew_sub(MDOC_HEAD, m, tok, line, ppos))
					return(0);
				flushed = 1;
				if ( ! mdoc_body_alloc(m, line, ppos, tok))
					return(0);
			}
			if ( ! mdoc_macro(m, c, line, la, pos, buf))
				return(0);
			break;
		}

		if ( ! flushed && mdoc_isdelim(p)) {
			if ( ! rew_sub(MDOC_HEAD, m, tok, line, ppos))
				return(0);
			flushed = 1;
			if ( ! mdoc_body_alloc(m, line, ppos, tok))
				return(0);
		}
	
		if ( ! mdoc_word_alloc(m, line, la, p))
			return(0);
	}

	/* Close the head and open the body, if applicable. */

	if ( ! flushed) {
		if ( ! rew_sub(MDOC_HEAD, m, tok, line, ppos))
			return(0);
		if ( ! mdoc_body_alloc(m, line, ppos, tok))
			return(0);
	}

	/* Standard appending of delimiters. */

	if (ppos > 1)
		return(1);
	return(append_delims(m, line, pos, buf));
}


static int
in_line_argn(MACRO_PROT_ARGS)
{
	int		  la, flushed, j, c, maxargs;
	struct mdoc_arg	 *arg;
	char		 *p;

	/* Fixed maximum arguments per macro, if applicable. */

	switch (tok) {
	case (MDOC_Ap):
		/* FALLTHROUGH */
	case (MDOC_No):
		/* FALLTHROUGH */
	case (MDOC_Ns):
		/* FALLTHROUGH */
	case (MDOC_Ux):
		maxargs = 0;
		break;
	case (MDOC_Xr):
		maxargs = 2;
		break;
	default:
		maxargs = 1;
		break;
	}

	/* Macro argument processing. */

	for (arg = NULL;; ) {
		la = *pos;
		c = mdoc_argv(m, line, tok, &arg, pos, buf);

		if (ARGV_WORD == c) {
			*pos = la;
			break;
		} 

		if (ARGV_EOLN == c)
			break;
		if (ARGV_ARG == c)
			continue;

		mdoc_argv_free(arg);
		return(0);
	}

	/* Open the element scope. */

	if ( ! mdoc_elem_alloc(m, line, ppos, tok, arg))
		return(0);

	/* Process element arguments. */

	for (flushed = j = 0; ; j++) {
		la = *pos;

		if (j == maxargs && ! flushed) {
			if ( ! rew_elem(m, tok))
				return(0);
			flushed = 1;
		}

		c = mdoc_args(m, line, pos, buf, tok, &p);

		if (ARGS_ERROR == c)
			return(0);
		if (ARGS_PUNCT == c)
			break;
		if (ARGS_EOLN == c)
			break;

		if (MDOC_MAX != (c = lookup(tok, p))) {
			if ( ! flushed && ! rew_elem(m, tok))
				return(0);
			flushed = 1;
			if ( ! mdoc_macro(m, c, line, la, pos, buf))
				return(0);
			break;
		}

		if ( ! (MDOC_IGNDELIM & mdoc_macros[tok].flags) &&
				! flushed && mdoc_isdelim(p)) {
			if ( ! rew_elem(m, tok))
				return(0);
			flushed = 1;
		}

		/* 
		 * XXX: this is a hack to work around groff's ugliness
		 * as regards `Xr' and extraneous arguments.  It should
		 * ideally be deprecated behaviour, but because this is
		 * code is no here, it's unlikely to be removed.
		 */
		if (MDOC_Xr == tok && j == maxargs) {
			if ( ! mdoc_elem_alloc(m, line, ppos, MDOC_Ns, NULL))
				return(0);
			if ( ! rew_elem(m, MDOC_Ns))
				return(0);
		}

		if ( ! mdoc_word_alloc(m, line, la, p))
			return(0);
	}

	/* Close out and append delimiters. */

	if ( ! flushed && ! rew_elem(m, tok))
		return(0);

	if (ppos > 1)
		return(1);
	return(append_delims(m, line, pos, buf));
}


static int
in_line_eoln(MACRO_PROT_ARGS)
{
	int		  c, w, la;
	struct mdoc_arg	 *arg;
	char		 *p;

	assert( ! (MDOC_PARSED & mdoc_macros[tok].flags));

	/* Parse macro arguments. */

	for (arg = NULL; ; ) {
		la = *pos;
		c = mdoc_argv(m, line, tok, &arg, pos, buf);

		if (ARGV_WORD == c) {
			*pos = la;
			break;
		}
		if (ARGV_EOLN == c) 
			break;
		if (ARGV_ARG == c)
			continue;

		mdoc_argv_free(arg);
		return(0);
	}

	/* Open element scope. */

	if ( ! mdoc_elem_alloc(m, line, ppos, tok, arg))
		return(0);

	/* Parse argument terms. */

	for (;;) {
		la = *pos;
		w = mdoc_args(m, line, pos, buf, tok, &p);

		if (ARGS_ERROR == w)
			return(0);
		if (ARGS_EOLN == w)
			break;

		c = ARGS_QWORD == w ? MDOC_MAX : lookup(tok, p);

		if (MDOC_MAX != c) {
			if ( ! rew_elem(m, tok))
				return(0);
			return(mdoc_macro(m, c, line, la, pos, buf));
		} 

		if ( ! mdoc_word_alloc(m, line, la, p))
			return(0);
	}

	/* Close out (no delimiters). */

	return(rew_elem(m, tok));
}


/* ARGSUSED */
static int
ctx_synopsis(MACRO_PROT_ARGS)
{

	/* If we're not in the SYNOPSIS, go straight to in-line. */
	if (SEC_SYNOPSIS != m->lastsec)
		return(in_line(m, tok, line, ppos, pos, buf));

	/* If we're a nested call, same place. */
	if (ppos > 1)
		return(in_line(m, tok, line, ppos, pos, buf));

	/*
	 * XXX: this will open a block scope; however, if later we end
	 * up formatting the block scope, then child nodes will inherit
	 * the formatting.  Be careful.
	 */

	return(blk_part_imp(m, tok, line, ppos, pos, buf));
}


/* ARGSUSED */
static int
obsolete(MACRO_PROT_ARGS)
{

	return(mdoc_pwarn(m, line, ppos, EOBS));
}


/*
 * Phrases occur within `Bl -column' entries, separated by `Ta' or tabs.
 * They're unusual because they're basically free-form text until a
 * macro is encountered.
 */
static int
phrase(struct mdoc *m, int line, int ppos, char *buf)
{
	int		  c, w, la, pos;
	char		 *p;

	for (pos = ppos; ; ) {
		la = pos;

		/* Note: no calling context! */
		w = mdoc_zargs(m, line, &pos, buf, 0, &p);

		if (ARGS_ERROR == w)
			return(0);
		if (ARGS_EOLN == w)
			break;

		c = ARGS_QWORD == w ? MDOC_MAX : lookup_raw(p);

		if (MDOC_MAX != c) {
			if ( ! mdoc_macro(m, c, line, la, &pos, buf))
				return(0);
			return(append_delims(m, line, &pos, buf));
		} 

		if ( ! mdoc_word_alloc(m, line, la, p))
			return(0);
	}

	return(1);
}