X-Git-Url: https://git.cameronkatri.com/mandoc.git/blobdiff_plain/e1d78876eec368e83465ee580da59a8cbe578000..91ab27befd54e154790aa66b308e8be09659b580:/roff.c

diff --git a/roff.c b/roff.c
index efcfcc50..7d76fb56 100644
--- a/roff.c
+++ b/roff.c
@@ -1,1286 +1,1444 @@
-/* $Id: roff.c,v 1.29 2008/12/01 16:14:34 kristaps Exp $ */
+/*	$Id: roff.c,v 1.125 2011/02/06 20:36:36 kristaps Exp $ */
 /*
- * Copyright (c) 2008 Kristaps Dzonsons <kristaps@kth.se>
+ * Copyright (c) 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
+ * Copyright (c) 2010, 2011 Ingo Schwarze <schwarze@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.
+ * 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.
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHORS DISCLAIM ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHORS 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.
  */
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
 #include <assert.h>
+#include <errno.h>
 #include <ctype.h>
-#include <err.h>
-#include <stdarg.h>
+#include <limits.h>
 #include <stdlib.h>
-#include <stdio.h>
 #include <string.h>
-#include <time.h>
-
-#include "libmdocml.h"
-#include "private.h"
-
-/* TODO: warn if Pp occurs before/after Sh etc. (see mdoc.samples). */
-
-/* TODO: warn about "X section only" macros. */
-
-/* TODO: warn about empty lists. */
-
-/* TODO: (warn) some sections need specific elements. */
-
-/* TODO: (warn) NAME section has particular order. */
-
-/* TODO: unify empty-content tags a la <br />. */
-
-/* TODO: macros with a set number of arguments? */
-
-#define	ROFF_MAXARG	  32
+#include <stdio.h>
 
-enum	roffd { 
-	ROFF_ENTER = 0, 
-	ROFF_EXIT 
+#include "mandoc.h"
+#include "roff.h"
+#include "libroff.h"
+#include "libmandoc.h"
+
+#define	RSTACK_MAX	128
+
+#define	ROFF_CTL(c) \
+	('.' == (c) || '\'' == (c))
+
+enum	rofft {
+	ROFF_ad,
+	ROFF_am,
+	ROFF_ami,
+	ROFF_am1,
+	ROFF_de,
+	ROFF_dei,
+	ROFF_de1,
+	ROFF_ds,
+	ROFF_el,
+	ROFF_hy,
+	ROFF_ie,
+	ROFF_if,
+	ROFF_ig,
+	ROFF_it,
+	ROFF_ne,
+	ROFF_nh,
+	ROFF_nr,
+	ROFF_ns,
+	ROFF_ps,
+	ROFF_rm,
+	ROFF_so,
+	ROFF_ta,
+	ROFF_tr,
+	ROFF_TS,
+	ROFF_TE,
+	ROFF_T_,
+	ROFF_EQ,
+	ROFF_EN,
+	ROFF_cblock,
+	ROFF_ccond, /* FIXME: remove this. */
+	ROFF_USERDEF,
+	ROFF_MAX
 };
 
-enum	rofftype { 
-	ROFF_COMMENT, 
-	ROFF_TEXT, 
-	ROFF_LAYOUT,
-	ROFF_SPECIAL
+enum	roffrule {
+	ROFFRULE_ALLOW,
+	ROFFRULE_DENY
 };
 
-#define	ROFFCALL_ARGS \
-	int tok, struct rofftree *tree, \
-	char *argv[], enum roffd type
-
-struct	rofftree;
-
-struct	rofftok {
-	int		(*cb)(ROFFCALL_ARGS);	/* Callback. */
-	const int	 *args;			/* Args (or NULL). */
-	const int	 *parents;
-	const int	 *children;
-	int		  ctx;
-	enum rofftype	  type;			/* Type of macro. */
-	int		  flags;
-#define	ROFF_PARSED	 (1 << 0)		/* "Parsed". */
-#define	ROFF_CALLABLE	 (1 << 1)		/* "Callable". */
-#define	ROFF_SHALLOW	 (1 << 2)		/* Nesting block. */
-#define	ROFF_LSCOPE	 (1 << 3)
+struct	roffstr {
+	char		*name; /* key of symbol */
+	char		*string; /* current value */
+	struct roffstr	*next; /* next in list */
 };
 
-struct	roffarg {
-	int		  flags;
-#define	ROFF_VALUE	 (1 << 0)		/* Has a value. */
+struct	roff {
+	struct roffnode	*last; /* leaf of stack */
+	mandocmsg	 msg; /* err/warn/fatal messages */
+	void		*data; /* privdata for messages */
+	enum roffrule	 rstack[RSTACK_MAX]; /* stack of !`ie' rules */
+	int		 rstackpos; /* position in rstack */
+	struct regset	*regs; /* read/writable registers */
+	struct roffstr	*first_string; /* user-defined strings & macros */
+	const char	*current_string; /* value of last called user macro */
+	struct tbl_node	*first_tbl; /* first table parsed */
+	struct tbl_node	*last_tbl; /* last table parsed */
+	struct tbl_node	*tbl; /* current table being parsed */
+	struct eqn_node	*last_eqn; /* last equation parsed */
+	struct eqn_node	*first_eqn; /* first equation parsed */
+	struct eqn_node	*eqn; /* current equation being parsed */
 };
 
 struct	roffnode {
-	int		  tok;			/* Token id. */
-	struct roffnode	 *parent;		/* Parent (or NULL). */
+	enum rofft	 tok; /* type of node */
+	struct roffnode	*parent; /* up one in stack */
+	int		 line; /* parse line */
+	int		 col; /* parse col */
+	char		*name; /* node name, e.g. macro name */
+	char		*end; /* end-rules: custom token */
+	int		 endspan; /* end-rules: next-line or infty */
+	enum roffrule	 rule; /* current evaluation rule */
 };
 
-struct	rofftree {
-	struct roffnode	 *last;			/* Last parsed node. */
-	char		 *cur;
-
-	time_t		  date;			/* `Dd' results. */
-	char		  os[64];		/* `Os' results. */
-	char		  title[64];		/* `Dt' results. */
-	char		  section[64];		/* `Dt' results. */
-	char		  volume[64];		/* `Dt' results. */
-
-	int		  state;
-#define	ROFF_PRELUDE	 (1 << 1)		/* In roff prelude. */
-#define	ROFF_PRELUDE_Os	 (1 << 2)		/* `Os' is parsed. */
-#define	ROFF_PRELUDE_Dt	 (1 << 3)		/* `Dt' is parsed. */
-#define	ROFF_PRELUDE_Dd	 (1 << 4)		/* `Dd' is parsed. */
-#define	ROFF_BODY	 (1 << 5)		/* In roff body. */
-
-	struct roffcb	  cb;
-	void		 *arg;
+#define	ROFF_ARGS	 struct roff *r, /* parse ctx */ \
+			 enum rofft tok, /* tok of macro */ \
+		 	 char **bufp, /* input buffer */ \
+			 size_t *szp, /* size of input buffer */ \
+			 int ln, /* parse line */ \
+			 int ppos, /* original pos in buffer */ \
+			 int pos, /* current pos in buffer */ \
+			 int *offs /* reset offset of buffer data */
+
+typedef	enum rofferr (*roffproc)(ROFF_ARGS);
+
+struct	roffmac {
+	const char	*name; /* macro name */
+	roffproc	 proc; /* process new macro */
+	roffproc	 text; /* process as child text of macro */
+	roffproc	 sub; /* process as child of macro */
+	int		 flags;
+#define	ROFFMAC_STRUCT	(1 << 0) /* always interpret */
+	struct roffmac	*next;
 };
 
-static	int		  roff_Dd(ROFFCALL_ARGS);
-static	int		  roff_Dt(ROFFCALL_ARGS);
-static	int		  roff_Os(ROFFCALL_ARGS);
-
-static	int		  roff_layout(ROFFCALL_ARGS);
-static	int		  roff_text(ROFFCALL_ARGS);
-static	int		  roff_noop(ROFFCALL_ARGS);
-static	int		  roff_depr(ROFFCALL_ARGS);
-
-static	struct roffnode	 *roffnode_new(int, struct rofftree *);
-static	void		  roffnode_free(struct rofftree *);
-
-static	void		  roff_warn(const struct rofftree *, 
-				const char *, char *, ...);
-static	void		  roff_err(const struct rofftree *, 
-				const char *, char *, ...);
-
-static	int		  roffscan(int, const int *);
-static	int		  rofffindtok(const char *);
-static	int		  rofffindarg(const char *);
-static	int		  rofffindcallable(const char *);
-static	int		  roffargs(const struct rofftree *,
-				int, char *, char **);
-static	int		  roffargok(int, int);
-static	int		  roffnextopt(const struct rofftree *,
-				int, char ***, char **);
-static	int		  roffparseopts(struct rofftree *, int, 
-				char ***, int *, char **);
-static	int 		  roffparse(struct rofftree *, char *);
-static	int		  textparse(const struct rofftree *, char *);
-
-
-static	const int roffarg_An[] = { ROFF_Split, ROFF_Nosplit, 
-	ROFF_ARGMAX };
-static	const int roffarg_Bd[] = { ROFF_Ragged, ROFF_Unfilled, 
-	ROFF_Literal, ROFF_File, ROFF_Offset, ROFF_Filled,
-	ROFF_Compact, ROFF_ARGMAX };
-static	const int roffarg_Bk[] = { ROFF_Words, ROFF_ARGMAX };
-static	const int roffarg_Ex[] = { ROFF_Std, ROFF_ARGMAX };
-static	const int roffarg_Rv[] = { ROFF_Std, ROFF_ARGMAX };
-static 	const int roffarg_Bl[] = { ROFF_Bullet, ROFF_Dash, 
-	ROFF_Hyphen, ROFF_Item, ROFF_Enum, ROFF_Tag, ROFF_Diag, 
-	ROFF_Hang, ROFF_Ohang, ROFF_Inset, ROFF_Column, ROFF_Offset, 
-	ROFF_Width, ROFF_Compact, ROFF_ARGMAX };
-static 	const int roffarg_St[] = {
-	ROFF_p1003_1_88, ROFF_p1003_1_90, ROFF_p1003_1_96,
-	ROFF_p1003_1_2001, ROFF_p1003_1_2004, ROFF_p1003_1,
-	ROFF_p1003_1b, ROFF_p1003_1b_93, ROFF_p1003_1c_95,
-	ROFF_p1003_1g_2000, ROFF_p1003_2_92, ROFF_p1387_2_95,
-	ROFF_p1003_2, ROFF_p1387_2, ROFF_isoC_90, ROFF_isoC_amd1,
-	ROFF_isoC_tcor1, ROFF_isoC_tcor2, ROFF_isoC_99, ROFF_ansiC,
-	ROFF_ansiC_89, ROFF_ansiC_99, ROFF_ieee754, ROFF_iso8802_3,
-	ROFF_xpg3, ROFF_xpg4, ROFF_xpg4_2, ROFF_xpg4_3, ROFF_xbd5,
-	ROFF_xcu5, ROFF_xsh5, ROFF_xns5, ROFF_xns5_2d2_0,
-	ROFF_xcurses4_2, ROFF_susv2, ROFF_susv3, ROFF_svid4,
-	ROFF_ARGMAX };
-
-static	const int roffchild_Bl[] = { ROFF_It, ROFF_El, ROFF_MAX };
-static	const int roffchild_Fo[] = { ROFF_Fa, ROFF_Fc, ROFF_MAX };
-static	const int roffchild_Rs[] = { ROFF_Re, ROFF__A, ROFF__B,
-	ROFF__D, ROFF__I, ROFF__J, ROFF__N, ROFF__O, ROFF__P,
-	ROFF__R, ROFF__T, ROFF__V, ROFF_MAX };
-
-static	const int roffparent_El[] = { ROFF_Bl, ROFF_It, ROFF_MAX };
-static	const int roffparent_Fc[] = { ROFF_Fo, ROFF_Fa, ROFF_MAX };
-static	const int roffparent_Oc[] = { ROFF_Oo, ROFF_MAX };
-static	const int roffparent_It[] = { ROFF_Bl, ROFF_It, ROFF_MAX };
-static	const int roffparent_Re[] = { ROFF_Rs, ROFF_MAX };
-
-/* Table of all known tokens. */
-static	const struct rofftok tokens[ROFF_MAX] = {
-	{   roff_noop, NULL, NULL, NULL, 0, ROFF_COMMENT, 0 }, /* \" */
-	{     roff_Dd, NULL, NULL, NULL, 0, ROFF_TEXT, 0 }, /* Dd */
-	{     roff_Dt, NULL, NULL, NULL, 0, ROFF_TEXT, 0 }, /* Dt */
-	{     roff_Os, NULL, NULL, NULL, 0, ROFF_TEXT, 0 }, /* Os */
-	{ roff_layout, NULL, NULL, NULL, ROFF_Sh, ROFF_LAYOUT, 0 }, /* Sh */
-	{ roff_layout, NULL, NULL, NULL, ROFF_Ss, ROFF_LAYOUT, 0 }, /* Ss */ 
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, 0 }, /* Pp */ /* XXX 0 args */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_LSCOPE }, /* D1 */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_LSCOPE }, /* Dl */
-	{ roff_layout, roffarg_Bd, NULL, NULL, 0, ROFF_LAYOUT, 0 }, 	/* Bd */
-	{   roff_noop, NULL, NULL, NULL, ROFF_Bd, ROFF_LAYOUT, 0 }, /* Ed */
-	{ roff_layout, roffarg_Bl, NULL, roffchild_Bl, 0, ROFF_LAYOUT, 0 }, /* Bl */
-	{   roff_noop, NULL, roffparent_El, NULL, ROFF_Bl, ROFF_LAYOUT, 0 }, /* El */
-	{ roff_layout, NULL, roffparent_It, NULL, ROFF_It, ROFF_LAYOUT, ROFF_PARSED | ROFF_SHALLOW }, /* It */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Ad */ /* FIXME */
-	{   roff_text, roffarg_An, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED }, /* An */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Ar */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, 0 }, /* Cd */ /* XXX man.4 only */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Cm */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Dv */ /* XXX needs arg */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Er */ /* XXX needs arg */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Ev */ /* XXX needs arg */
-	{   roff_text, roffarg_Ex, NULL, NULL, 0, ROFF_TEXT, 0 }, /* Ex */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Fa */ /* XXX needs arg */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, 0 }, /* Fd */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Fl */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Fn */ /* XXX needs arg */ /* FIXME */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED }, /* Ft */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Ic */ /* XXX needs arg */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, 0 }, /* In */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Li */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, 0 }, /* Nd */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Nm */ /* FIXME */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE | ROFF_LSCOPE }, /* Op */
-	{   roff_depr, NULL, NULL, NULL, 0, ROFF_TEXT, 0 }, /* Ot */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Pa */
-	{   roff_text, roffarg_Rv, NULL, NULL, 0, ROFF_TEXT, 0 }, /* Rv */
-	{   roff_text, roffarg_St, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* St */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Va */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Vt */ /* XXX needs arg */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Xr */ /* XXX needs arg */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED }, /* %A */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE}, /* %B */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, 0 }, /* %D */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE}, /* %I */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE}, /* %J */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, 0 }, /* %N */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, 0 }, /* %O */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, 0 }, /* %P */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, 0 }, /* %R */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED }, /* %T */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, 0 }, /* %V */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Ac */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Ao */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE | ROFF_LSCOPE }, /* Aq */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, 0 }, /* At */ /* XXX at most 2 args */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Bc */
-	{ roff_layout, NULL, NULL, NULL, 0, ROFF_LAYOUT, 0 }, /* Bf */ /* FIXME */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Bo */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE | ROFF_LSCOPE }, /* Bq */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED }, /* Bsx */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED }, /* Bx */
-	{        NULL, NULL, NULL, NULL, 0, ROFF_SPECIAL, 0 },	/* Db */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Dc */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Do */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE | ROFF_LSCOPE }, /* Dq */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Ec */
-	{   roff_noop, NULL, NULL, NULL, ROFF_Bf, ROFF_LAYOUT, 0 }, /* Ef */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Em */ /* XXX needs arg */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Eo */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED }, /* Fx */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED }, /* Ms */
-	{   NULL, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* No */
-	{        NULL, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Ns */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED }, /* Nx */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED }, /* Ox */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Pc */
-	{        NULL, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED }, /* Pf */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Po */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE | ROFF_LSCOPE }, /* Pq */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Qc */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Ql */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Qo */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE | ROFF_LSCOPE }, /* Qq */
-	{   roff_noop, NULL, roffparent_Re, NULL, ROFF_Rs, ROFF_LAYOUT, 0 }, /* Re */
-	{ roff_layout, NULL, NULL, roffchild_Rs, 0, ROFF_LAYOUT, 0 },	/* Rs */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Sc */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* So */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE | ROFF_LSCOPE }, /* Sq */
-	{        NULL, NULL, NULL, NULL, 0, ROFF_SPECIAL, 0 }, /* Sm */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Sx */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Sy */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Tn */
-	{   roff_text, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED }, /* Ux */
-	{   NULL, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Xc */
-	{   NULL, NULL, NULL, NULL, 0, ROFF_TEXT, ROFF_PARSED | ROFF_CALLABLE }, /* Xo */
-	{ roff_layout, NULL, NULL, roffchild_Fo, 0, ROFF_LAYOUT, 0 }, /* Fo */
-	{   roff_noop, NULL, roffparent_Fc, NULL, ROFF_Fo, ROFF_LAYOUT, 0 }, /* Fc */
-	{ roff_layout, NULL, NULL, NULL, 0, ROFF_LAYOUT, 0 }, /* Oo */
-	{   roff_noop, NULL, roffparent_Oc, NULL, ROFF_Oo, ROFF_LAYOUT, 0 }, /* Oc */
-	{ roff_layout, roffarg_Bk, NULL, NULL, 0, ROFF_LAYOUT, 0 }, /* Bk */
-	{   roff_noop, NULL, NULL, NULL, ROFF_Bk, ROFF_LAYOUT, 0 }, /* Ek */
-	{        NULL, NULL, NULL, NULL, 0, ROFF_TEXT, 0 }, /* Bt */
-	{        NULL, NULL, NULL, NULL, 0, ROFF_TEXT, 0 }, /* Hf */
-	{   roff_depr, NULL, NULL, NULL, 0, ROFF_TEXT, 0 }, /* Fr */
-	{        NULL, NULL, NULL, NULL, 0, ROFF_TEXT, 0 }, /* Ud */
-	};
-
-/* Table of all known token arguments. */
-static	const int tokenargs[ROFF_ARGMAX] = {
-	0,		0,		0,		0,
-	0,		ROFF_VALUE,	ROFF_VALUE,	0,
-	0,		0,		0,		0,
-	0,		0,		0,		0,
-	0,		0,		ROFF_VALUE,	0,
-	0,		0,		0,		0,
-	0,		0,		0,		0,
-	0,		0,		0,		0,
-	0,		0,		0,		0,
-	0,		0,		0,		0,
-	0,		0,		0,		0,
-	0,		0,		0,		0,
-	0,		0,		0,		0,
-	0,		0,		0,		0,
-	0,		0,		0,		0,
-	};
-
-const	char *const toknamesp[ROFF_MAX] = {		 
-	"\\\"",		"Dd",		"Dt",		"Os",
-	"Sh",		"Ss",		"Pp",		"D1",
-	"Dl",		"Bd",		"Ed",		"Bl",
-	"El",		"It",		"Ad",		"An",
-	"Ar",		"Cd",		"Cm",		"Dv",
-	"Er",		"Ev",		"Ex",		"Fa",
-	"Fd",		"Fl",		"Fn",		"Ft",
-	"Ic",		"In",		"Li",		"Nd",
-	"Nm",		"Op",		"Ot",		"Pa",
-	"Rv",		"St",		"Va",		"Vt",
-	/* LINTED */
-	"Xr",		"\%A",		"\%B",		"\%D",
-	/* LINTED */
-	"\%I",		"\%J",		"\%N",		"\%O",
-	/* LINTED */
-	"\%P",		"\%R",		"\%T",		"\%V",
-	"Ac",		"Ao",		"Aq",		"At",
-	"Bc",		"Bf",		"Bo",		"Bq",
-	"Bsx",		"Bx",		"Db",		"Dc",
-	"Do",		"Dq",		"Ec",		"Ef",
-	"Em",		"Eo",		"Fx",		"Ms",
-	"No",		"Ns",		"Nx",		"Ox",
-	"Pc",		"Pf",		"Po",		"Pq",
-	"Qc",		"Ql",		"Qo",		"Qq",
-	"Re",		"Rs",		"Sc",		"So",
-	"Sq",		"Sm",		"Sx",		"Sy",
-	"Tn",		"Ux",		"Xc",		"Xo",
-	"Fo",		"Fc",		"Oo",		"Oc",
-	"Bk",		"Ek",		"Bt",		"Hf",
-	"Fr",		"Ud",
-	};
-
-const	char *const tokargnamesp[ROFF_ARGMAX] = {		 
-	"split",		"nosplit",		"ragged",
-	"unfilled",		"literal",		"file",		 
-	"offset",		"bullet",		"dash",		 
-	"hyphen",		"item",			"enum",		 
-	"tag",			"diag",			"hang",		 
-	"ohang",		"inset",		"column",	 
-	"width",		"compact",		"std",	 
-	"p1003.1-88",		"p1003.1-90",		"p1003.1-96",
-	"p1003.1-2001",		"p1003.1-2004",		"p1003.1",
-	"p1003.1b",		"p1003.1b-93",		"p1003.1c-95",
-	"p1003.1g-2000",	"p1003.2-92",		"p1387.2-95",
-	"p1003.2",		"p1387.2",		"isoC-90",
-	"isoC-amd1",		"isoC-tcor1",		"isoC-tcor2",
-	"isoC-99",		"ansiC",		"ansiC-89",
-	"ansiC-99",		"ieee754",		"iso8802-3",
-	"xpg3",			"xpg4",			"xpg4.2",
-	"xpg4.3",		"xbd5",			"xcu5",
-	"xsh5",			"xns5",			"xns5.2d2.0",
-	"xcurses4.2",		"susv2",		"susv3",
-	"svid4",		"filled",		"words",
-	};
-
-const	char *const *toknames = toknamesp;
-const	char *const *tokargnames = tokargnamesp;
-
-
-int
-roff_free(struct rofftree *tree, int flush)
-{
-	int		 error, t;
-	struct roffnode	*n;
+static	enum rofferr	 roff_block(ROFF_ARGS);
+static	enum rofferr	 roff_block_text(ROFF_ARGS);
+static	enum rofferr	 roff_block_sub(ROFF_ARGS);
+static	enum rofferr	 roff_cblock(ROFF_ARGS);
+static	enum rofferr	 roff_ccond(ROFF_ARGS);
+static	enum rofferr	 roff_cond(ROFF_ARGS);
+static	enum rofferr	 roff_cond_text(ROFF_ARGS);
+static	enum rofferr	 roff_cond_sub(ROFF_ARGS);
+static	enum rofferr	 roff_ds(ROFF_ARGS);
+static	enum roffrule	 roff_evalcond(const char *, int *);
+static	void		 roff_freestr(struct roff *);
+static	char		*roff_getname(struct roff *, char **, int, int);
+static	const char	*roff_getstrn(const struct roff *, 
+				const char *, size_t);
+static	enum rofferr	 roff_line_ignore(ROFF_ARGS);
+static	enum rofferr	 roff_nr(ROFF_ARGS);
+static	int		 roff_res(struct roff *, 
+				char **, size_t *, int);
+static	enum rofferr	 roff_rm(ROFF_ARGS);
+static	void		 roff_setstr(struct roff *,
+				const char *, const char *, int);
+static	enum rofferr	 roff_so(ROFF_ARGS);
+static	enum rofferr	 roff_TE(ROFF_ARGS);
+static	enum rofferr	 roff_TS(ROFF_ARGS);
+static	enum rofferr	 roff_EQ(ROFF_ARGS);
+static	enum rofferr	 roff_EN(ROFF_ARGS);
+static	enum rofferr	 roff_T_(ROFF_ARGS);
+static	enum rofferr	 roff_userdef(ROFF_ARGS);
+
+/* See roff_hash_find() */
+
+#define	ASCII_HI	 126
+#define	ASCII_LO	 33
+#define	HASHWIDTH	(ASCII_HI - ASCII_LO + 1)
+
+static	struct roffmac	*hash[HASHWIDTH];
+
+static	struct roffmac	 roffs[ROFF_MAX] = {
+	{ "ad", roff_line_ignore, NULL, NULL, 0, NULL },
+	{ "am", roff_block, roff_block_text, roff_block_sub, 0, NULL },
+	{ "ami", roff_block, roff_block_text, roff_block_sub, 0, NULL },
+	{ "am1", roff_block, roff_block_text, roff_block_sub, 0, NULL },
+	{ "de", roff_block, roff_block_text, roff_block_sub, 0, NULL },
+	{ "dei", roff_block, roff_block_text, roff_block_sub, 0, NULL },
+	{ "de1", roff_block, roff_block_text, roff_block_sub, 0, NULL },
+	{ "ds", roff_ds, NULL, NULL, 0, NULL },
+	{ "el", roff_cond, roff_cond_text, roff_cond_sub, ROFFMAC_STRUCT, NULL },
+	{ "hy", roff_line_ignore, NULL, NULL, 0, NULL },
+	{ "ie", roff_cond, roff_cond_text, roff_cond_sub, ROFFMAC_STRUCT, NULL },
+	{ "if", roff_cond, roff_cond_text, roff_cond_sub, ROFFMAC_STRUCT, NULL },
+	{ "ig", roff_block, roff_block_text, roff_block_sub, 0, NULL },
+	{ "it", roff_line_ignore, NULL, NULL, 0, NULL },
+	{ "ne", roff_line_ignore, NULL, NULL, 0, NULL },
+	{ "nh", roff_line_ignore, NULL, NULL, 0, NULL },
+	{ "nr", roff_nr, NULL, NULL, 0, NULL },
+	{ "ns", roff_line_ignore, NULL, NULL, 0, NULL },
+	{ "ps", roff_line_ignore, NULL, NULL, 0, NULL },
+	{ "rm", roff_rm, NULL, NULL, 0, NULL },
+	{ "so", roff_so, NULL, NULL, 0, NULL },
+	{ "ta", roff_line_ignore, NULL, NULL, 0, NULL },
+	{ "tr", roff_line_ignore, NULL, NULL, 0, NULL },
+	{ "TS", roff_TS, NULL, NULL, 0, NULL },
+	{ "TE", roff_TE, NULL, NULL, 0, NULL },
+	{ "T&", roff_T_, NULL, NULL, 0, NULL },
+	{ "EQ", roff_EQ, NULL, NULL, 0, NULL },
+	{ "EN", roff_EN, NULL, NULL, 0, NULL },
+	{ ".", roff_cblock, NULL, NULL, 0, NULL },
+	{ "\\}", roff_ccond, NULL, NULL, 0, NULL },
+	{ NULL, roff_userdef, NULL, NULL, 0, NULL },
+};
 
-	error = 0;
+static	void		 roff_free1(struct roff *);
+static	enum rofft	 roff_hash_find(const char *, size_t);
+static	void		 roff_hash_init(void);
+static	void		 roffnode_cleanscope(struct roff *);
+static	void		 roffnode_push(struct roff *, enum rofft,
+				const char *, int, int);
+static	void		 roffnode_pop(struct roff *);
+static	enum rofft	 roff_parse(struct roff *, const char *, int *);
+static	int		 roff_parse_nat(const char *, unsigned int *);
 
-	if ( ! flush)
-		goto end;
+/* See roff_hash_find() */
+#define	ROFF_HASH(p)	(p[0] - ASCII_LO)
 
-	error = 1;
+static void
+roff_hash_init(void)
+{
+	struct roffmac	 *n;
+	int		  buc, i;
 
-	if (ROFF_PRELUDE & tree->state) {
-		roff_err(tree, NULL, "prelude never finished");
-		goto end;
-	} 
+	for (i = 0; i < (int)ROFF_USERDEF; i++) {
+		assert(roffs[i].name[0] >= ASCII_LO);
+		assert(roffs[i].name[0] <= ASCII_HI);
 
-	for (n = tree->last; n; n = n->parent) {
-		if (0 != tokens[n->tok].ctx) 
-			continue;
-		roff_err(tree, NULL, "closing explicit scope `%s'", 
-				toknames[n->tok]);
-		goto end;
-	}
+		buc = ROFF_HASH(roffs[i].name);
 
-	while (tree->last) {
-		t = tree->last->tok;
-		if ( ! (*tokens[t].cb)(t, tree, NULL, ROFF_EXIT))
-			goto end;
+		if (NULL != (n = hash[buc])) {
+			for ( ; n->next; n = n->next)
+				/* Do nothing. */ ;
+			n->next = &roffs[i];
+		} else
+			hash[buc] = &roffs[i];
 	}
-
-	error = 0;
-
-end:
-
-	while (tree->last) 
-		roffnode_free(tree);
-
-	free(tree);
-
-	return(error ? 0 : 1);
 }
 
 
-struct rofftree *
-roff_alloc(const struct roffcb *cb, void *args)
+/*
+ * Look up a roff token by its name.  Returns ROFF_MAX if no macro by
+ * the nil-terminated string name could be found.
+ */
+static enum rofft
+roff_hash_find(const char *p, size_t s)
 {
-	struct rofftree	*tree;
+	int		 buc;
+	struct roffmac	*n;
 
-	assert(args);
-	assert(cb);
+	/*
+	 * libroff has an extremely simple hashtable, for the time
+	 * being, which simply keys on the first character, which must
+	 * be printable, then walks a chain.  It works well enough until
+	 * optimised.
+	 */
 
-	if (NULL == (tree = calloc(1, sizeof(struct rofftree))))
-		err(1, "calloc");
+	if (p[0] < ASCII_LO || p[0] > ASCII_HI)
+		return(ROFF_MAX);
 
-	tree->state = ROFF_PRELUDE;
-	tree->arg = args;
+	buc = ROFF_HASH(p);
 
-	(void)memcpy(&tree->cb, cb, sizeof(struct roffcb));
+	if (NULL == (n = hash[buc]))
+		return(ROFF_MAX);
+	for ( ; n; n = n->next)
+		if (0 == strncmp(n->name, p, s) && '\0' == n->name[(int)s])
+			return((enum rofft)(n - roffs));
 
-	return(tree);
+	return(ROFF_MAX);
 }
 
 
-int
-roff_engine(struct rofftree *tree, char *buf)
+/*
+ * Pop the current node off of the stack of roff instructions currently
+ * pending.
+ */
+static void
+roffnode_pop(struct roff *r)
 {
+	struct roffnode	*p;
 
-	tree->cur = buf;
-	assert(buf);
+	assert(r->last);
+	p = r->last; 
 
-	if (0 == *buf) {
-		roff_err(tree, buf, "blank line");
-		return(0);
-	} else if ('.' != *buf)
-		return(textparse(tree, buf));
+	if (ROFF_el == p->tok)
+		if (r->rstackpos > -1)
+			r->rstackpos--;
 
-	return(roffparse(tree, buf));
+	r->last = r->last->parent;
+	free(p->name);
+	free(p->end);
+	free(p);
 }
 
 
-static int
-textparse(const struct rofftree *tree, char *buf)
+/*
+ * Push a roff node onto the instruction stack.  This must later be
+ * removed with roffnode_pop().
+ */
+static void
+roffnode_push(struct roff *r, enum rofft tok, const char *name,
+		int line, int col)
 {
+	struct roffnode	*p;
+
+	p = mandoc_calloc(1, sizeof(struct roffnode));
+	p->tok = tok;
+	if (name)
+		p->name = mandoc_strdup(name);
+	p->parent = r->last;
+	p->line = line;
+	p->col = col;
+	p->rule = p->parent ? p->parent->rule : ROFFRULE_DENY;
 
-	return((*tree->cb.roffdata)(tree->arg, 1, buf));
+	r->last = p;
 }
 
 
-static int
-roffargs(const struct rofftree *tree, 
-		int tok, char *buf, char **argv)
+static void
+roff_free1(struct roff *r)
 {
-	int		 i;
-	char		*p;
-
-	assert(tok >= 0 && tok < ROFF_MAX);
-	assert('.' == *buf);
-
-	p = buf;
-
-	/* LINTED */
-	for (i = 0; *buf && i < ROFF_MAXARG; i++) {
-		if ('\"' == *buf) {
-			argv[i] = ++buf;
-			while (*buf && '\"' != *buf)
-				buf++;
-			if (0 == *buf) {
-				roff_err(tree, argv[i], "unclosed "
-						"quote in argument "
-						"list for `%s'", 
-						toknames[tok]);
-				return(0);
-			}
-		} else { 
-			argv[i] = buf++;
-			while (*buf && ! isspace(*buf))
-				buf++;
-			if (0 == *buf)
-				continue;
-		}
-		*buf++ = 0;
-		while (*buf && isspace(*buf))
-			buf++;
+	struct tbl_node	*t;
+	struct eqn_node	*e;
+
+	while (NULL != (t = r->first_tbl)) {
+		r->first_tbl = t->next;
+		tbl_free(t);
 	}
-	
-	assert(i > 0);
-	if (ROFF_MAXARG == i && *buf) {
-		roff_err(tree, p, "too many arguments for `%s'", toknames
-				[tok]);
-		return(0);
+
+	r->first_tbl = r->last_tbl = r->tbl = NULL;
+
+	while (NULL != (e = r->first_eqn)) {
+		r->first_eqn = e->next;
+		eqn_free(e);
 	}
 
-	argv[i] = NULL;
-	return(1);
-}
+	r->first_eqn = r->last_eqn = r->eqn = NULL;
 
+	while (r->last)
+		roffnode_pop(r);
 
-static int
-roffscan(int tok, const int *tokv)
-{
+	roff_freestr(r);
+}
 
-	if (NULL == tokv)
-		return(1);
 
-	for ( ; ROFF_MAX != *tokv; tokv++) 
-		if (tok == *tokv)
-			return(1);
+void
+roff_reset(struct roff *r)
+{
 
-	return(0);
+	roff_free1(r);
 }
 
 
-static int
-roffparse(struct rofftree *tree, char *buf)
+void
+roff_free(struct roff *r)
 {
-	int		  tok, t;
-	struct roffnode	 *n;
-	char		 *argv[ROFF_MAXARG];
-	char		**argvp;
 
-	if (0 != *buf && 0 != *(buf + 1) && 0 != *(buf + 2))
-		if (0 == strncmp(buf, ".\\\"", 3))
-			return(1);
-
-	if (ROFF_MAX == (tok = rofffindtok(buf + 1))) {
-		roff_err(tree, buf + 1, "bogus line macro");
-		return(0);
-	} else if (NULL == tokens[tok].cb) {
-		roff_err(tree, buf + 1, "unsupported macro `%s'", 
-				toknames[tok]);
-		return(0);
-	}
+	roff_free1(r);
+	free(r);
+}
 
-	assert(ROFF___ != tok);
-	if ( ! roffargs(tree, tok, buf, argv)) 
-		return(0);
 
-	argvp = (char **)argv;
+struct roff *
+roff_alloc(struct regset *regs, void *data, const mandocmsg msg)
+{
+	struct roff	*r;
 
-	/* 
-	 * Prelude macros break some assumptions, so branch now. 
-	 */
+	r = mandoc_calloc(1, sizeof(struct roff));
+	r->regs = regs;
+	r->msg = msg;
+	r->data = data;
+	r->rstackpos = -1;
 	
-	if (ROFF_PRELUDE & tree->state) {
-		assert(NULL == tree->last);
-		return((*tokens[tok].cb)(tok, tree, argvp, ROFF_ENTER));
-	} 
-
-	assert(ROFF_BODY & tree->state);
+	roff_hash_init();
+	return(r);
+}
 
-	/* 
-	 * First check that our possible parents and parent's possible
-	 * children are satisfied.  
-	 */
 
-	if (tree->last && ! roffscan
-			(tree->last->tok, tokens[tok].parents)) {
-		roff_err(tree, *argvp, "`%s' has invalid parent `%s'",
-				toknames[tok], 
-				toknames[tree->last->tok]);
-		return(0);
-	} 
+/*
+ * Pre-filter each and every line for reserved words (one beginning with
+ * `\*', e.g., `\*(ab').  These must be handled before the actual line
+ * is processed. 
+ */
+static int
+roff_res(struct roff *r, char **bufp, size_t *szp, int pos)
+{
+	const char	*stesc;	/* start of an escape sequence ('\\') */
+	const char	*stnam;	/* start of the name, after "[(*" */
+	const char	*cp;	/* end of the name, e.g. before ']' */
+	const char	*res;	/* the string to be substituted */
+	int		 i, maxl;
+	size_t		 nsz;
+	char		*n;
 
-	if (tree->last && ! roffscan
-			(tok, tokens[tree->last->tok].children)) {
-		roff_err(tree, *argvp, "`%s' is invalid child of `%s'",
-				toknames[tok],
-				toknames[tree->last->tok]);
-		return(0);
-	}
+	/* Search for a leading backslash and save a pointer to it. */
 
-	/*
-	 * Branch if we're not a layout token.
-	 */
+	cp = *bufp + pos;
+	while (NULL != (cp = strchr(cp, '\\'))) {
+		stesc = cp++;
 
-	if (ROFF_LAYOUT != tokens[tok].type)
-		return((*tokens[tok].cb)(tok, tree, argvp, ROFF_ENTER));
-	if (0 == tokens[tok].ctx)
-		return((*tokens[tok].cb)(tok, tree, argvp, ROFF_ENTER));
+		/*
+		 * The second character must be an asterisk.
+		 * If it isn't, skip it anyway:  It is escaped,
+		 * so it can't start another escape sequence.
+		 */
 
-	/*
-	 * First consider implicit-end tags, like as follows:
-	 *	.Sh SECTION 1
-	 *	.Sh SECTION 2
-	 * In this, we want to close the scope of the NAME section.  If
-	 * there's an intermediary implicit-end tag, such as
-	 *	.Sh SECTION 1
-	 *	.Ss Subsection 1
-	 *	.Sh SECTION 2
-	 * then it must be closed as well.
-	 */
+		if ('\0' == *cp)
+			return(1);
+		if ('*' != *cp++)
+			continue;
 
-	if (tok == tokens[tok].ctx) {
-		/* 
-		 * First search up to the point where we must close.
-		 * If one doesn't exist, then we can open a new scope.
+		/*
+		 * The third character decides the length
+		 * of the name of the string.
+		 * Save a pointer to the name.
 		 */
 
-		for (n = tree->last; n; n = n->parent) {
-			assert(0 == tokens[n->tok].ctx ||
-					n->tok == tokens[n->tok].ctx);
-			if (n->tok == tok)
-				break;
-			if (ROFF_SHALLOW & tokens[tok].flags) {
-				n = NULL;
+		switch (*cp) {
+		case ('\0'):
+			return(1);
+		case ('('):
+			cp++;
+			maxl = 2;
+			break;
+		case ('['):
+			cp++;
+			maxl = 0;
+			break;
+		default:
+			maxl = 1;
+			break;
+		}
+		stnam = cp;
+
+		/* Advance to the end of the name. */
+
+		for (i = 0; 0 == maxl || i < maxl; i++, cp++) {
+			if ('\0' == *cp)
+				return(1); /* Error. */
+			if (0 == maxl && ']' == *cp)
 				break;
-			}
-			if (tokens[n->tok].ctx == n->tok)
-				continue;
-			roff_err(tree, *argv, "`%s' breaks `%s' scope",
-					toknames[tok], toknames[n->tok]);
-			return(0);
 		}
 
 		/*
-		 * Create a new scope, as no previous one exists to
-		 * close out.
+		 * Retrieve the replacement string; if it is
+		 * undefined, resume searching for escapes.
 		 */
 
-		if (NULL == n)
-			return((*tokens[tok].cb)(tok, tree, argvp, ROFF_ENTER));
+		res = roff_getstrn(r, stnam, (size_t)i);
 
-		/* 
-		 * Close out all intermediary scoped blocks, then hang
-		 * the current scope from our predecessor's parent.
-		 */
+		if (NULL == res) {
+			cp -= maxl ? 1 : 0;
+			continue;
+		}
+
+		/* Replace the escape sequence by the string. */
+
+		nsz = *szp + strlen(res) + 1;
+		n = mandoc_malloc(nsz);
 
-		do {
-			t = tree->last->tok;
-			if ( ! (*tokens[t].cb)(t, tree, NULL, ROFF_EXIT))
-				return(0);
-		} while (t != tok);
+		strlcpy(n, *bufp, (size_t)(stesc - *bufp + 1));
+		strlcat(n, res, nsz);
+		strlcat(n, cp + (maxl ? 0 : 1), nsz);
 
-		return((*tokens[tok].cb)(tok, tree, argvp, ROFF_ENTER));
+		free(*bufp);
+
+		*bufp = n;
+		*szp = nsz;
+		return(0);
 	}
 
+	return(1);
+}
+
+
+enum rofferr
+roff_parseln(struct roff *r, int ln, char **bufp, 
+		size_t *szp, int pos, int *offs)
+{
+	enum rofft	 t;
+	enum rofferr	 e;
+	int		 ppos;
+
 	/*
-	 * Now consider explicit-end tags, where we want to close back
-	 * to a specific tag.  Example:
-	 * 	.Bl
-	 * 	.It Item.
-	 * 	.El
-	 * In this, the `El' tag closes out the scope of `Bl'.
+	 * Run the reserved-word filter only if we have some reserved
+	 * words to fill in.
 	 */
 
-	assert(tok != tokens[tok].ctx && 0 != tokens[tok].ctx);
+	if (r->first_string && ! roff_res(r, bufp, szp, pos))
+		return(ROFF_REPARSE);
 
-	for (n = tree->last; n; n = n->parent)
-		if (n->tok != tokens[tok].ctx) {
-			if (n->tok == tokens[n->tok].ctx)
-				continue;
-			roff_err(tree, *argv, "`%s' breaks `%s' scope",
-					toknames[tok], toknames[n->tok]);
-			return(0);
-		} else
-			break;
+	/*
+	 * First, if a scope is open and we're not a macro, pass the
+	 * text through the macro's filter.  If a scope isn't open and
+	 * we're not a macro, just let it through.
+	 * Finally, if there's an equation scope open, divert it into it
+	 * no matter our state.
+	 */
 
+	if (r->last && ! ROFF_CTL((*bufp)[pos])) {
+		t = r->last->tok;
+		assert(roffs[t].text);
+		e = (*roffs[t].text)
+			(r, t, bufp, szp, ln, pos, pos, offs);
+		assert(ROFF_IGN == e || ROFF_CONT == e);
+		if (ROFF_CONT != e)
+			return(e);
+		if (r->eqn)
+			return(eqn_read(&r->eqn, ln, *bufp, *offs));
+		if (r->tbl)
+			return(tbl_read(r->tbl, ln, *bufp, *offs));
+		return(ROFF_CONT);
+	} else if ( ! ROFF_CTL((*bufp)[pos])) {
+		if (r->eqn)
+			return(eqn_read(&r->eqn, ln, *bufp, *offs));
+		if (r->tbl)
+			return(tbl_read(r->tbl, ln, *bufp, *offs));
+		return(ROFF_CONT);
+	} else if (r->eqn)
+		return(eqn_read(&r->eqn, ln, *bufp, *offs));
 
-	if (NULL == n) {
-		roff_err(tree, *argv, "`%s' has no starting tag `%s'",
-				toknames[tok], 
-				toknames[tokens[tok].ctx]);
-		return(0);
+	/*
+	 * If a scope is open, go to the child handler for that macro,
+	 * as it may want to preprocess before doing anything with it.
+	 * Don't do so if an equation is open.
+	 */
+
+	if (r->last) {
+		t = r->last->tok;
+		assert(roffs[t].sub);
+		return((*roffs[t].sub)
+				(r, t, bufp, szp, 
+				 ln, pos, pos, offs));
 	}
 
-	/* LINTED */
-	do {
-		t = tree->last->tok;
-		if ( ! (*tokens[t].cb)(t, tree, NULL, ROFF_EXIT))
-			return(0);
-	} while (t != tokens[tok].ctx);
+	/*
+	 * Lastly, as we've no scope open, try to look up and execute
+	 * the new macro.  If no macro is found, simply return and let
+	 * the compilers handle it.
+	 */
+
+	ppos = pos;
+	if (ROFF_MAX == (t = roff_parse(r, *bufp, &pos)))
+		return(ROFF_CONT);
 
-	return(1);
+	assert(roffs[t].proc);
+	return((*roffs[t].proc)
+			(r, t, bufp, szp, 
+			 ln, ppos, pos, offs));
 }
 
 
-static int
-rofffindarg(const char *name)
+void
+roff_endparse(struct roff *r)
 {
-	size_t		 i;
 
-	/* FIXME: use a table, this is slow but ok for now. */
+	if (r->last)
+		(*r->msg)(MANDOCERR_SCOPEEXIT, r->data,
+				r->last->line, r->last->col, NULL);
 
-	/* LINTED */
-	for (i = 0; i < ROFF_ARGMAX; i++)
-		/* LINTED */
-		if (0 == strcmp(name, tokargnames[i]))
-			return((int)i);
-	
-	return(ROFF_ARGMAX);
+	if (r->eqn) {
+		(*r->msg)(MANDOCERR_SCOPEEXIT, r->data, 
+				r->eqn->line, r->eqn->pos, NULL);
+		eqn_end(r->eqn);
+		r->eqn = NULL;
+	}
+
+	if (r->tbl) {
+		(*r->msg)(MANDOCERR_SCOPEEXIT, r->data, 
+				r->tbl->line, r->tbl->pos, NULL);
+		tbl_end(r->tbl);
+		r->tbl = NULL;
+	}
 }
 
 
-static int
-rofffindtok(const char *buf)
+/*
+ * Parse a roff node's type from the input buffer.  This must be in the
+ * form of ".foo xxx" in the usual way.
+ */
+static enum rofft
+roff_parse(struct roff *r, const char *buf, int *pos)
 {
-	char		 token[4];
-	int		 i;
+	const char	*mac;
+	size_t		 maclen;
+	enum rofft	 t;
+
+	assert(ROFF_CTL(buf[*pos]));
+	(*pos)++;
 
-	for (i = 0; *buf && ! isspace(*buf) && i < 3; i++, buf++)
-		token[i] = *buf;
+	while (' ' == buf[*pos] || '\t' == buf[*pos])
+		(*pos)++;
 
-	if (i == 3) 
+	if ('\0' == buf[*pos])
 		return(ROFF_MAX);
 
-	token[i] = 0;
+	mac = buf + *pos;
+	maclen = strcspn(mac, " \\\t\0");
 
-	/* FIXME: use a table, this is slow but ok for now. */
+	t = (r->current_string = roff_getstrn(r, mac, maclen))
+	    ? ROFF_USERDEF : roff_hash_find(mac, maclen);
 
-	/* LINTED */
-	for (i = 0; i < ROFF_MAX; i++)
-		/* LINTED */
-		if (0 == strcmp(toknames[i], token))
-			return((int)i);
+	*pos += maclen;
+	while (buf[*pos] && ' ' == buf[*pos])
+		(*pos)++;
 
-	return(ROFF_MAX);
+	return(t);
 }
 
 
 static int
-roffispunct(const char *p)
+roff_parse_nat(const char *buf, unsigned int *res)
 {
+	char		*ep;
+	long		 lval;
 
-	if (0 == *p)
+	errno = 0;
+	lval = strtol(buf, &ep, 10);
+	if (buf[0] == '\0' || *ep != '\0')
 		return(0);
-	if (0 != *(p + 1))
+	if ((errno == ERANGE && 
+			(lval == LONG_MAX || lval == LONG_MIN)) ||
+			(lval > INT_MAX || lval < 0))
 		return(0);
 
-	switch (*p) {
-	case('{'):
-		/* FALLTHROUGH */
-	case('.'):
-		/* FALLTHROUGH */
-	case(','):
-		/* FALLTHROUGH */
-	case(';'):
-		/* FALLTHROUGH */
-	case(':'):
-		/* FALLTHROUGH */
-	case('?'):
-		/* FALLTHROUGH */
-	case('!'):
+	*res = (unsigned int)lval;
+	return(1);
+}
+
+
+/* ARGSUSED */
+static enum rofferr
+roff_cblock(ROFF_ARGS)
+{
+
+	/*
+	 * A block-close `..' should only be invoked as a child of an
+	 * ignore macro, otherwise raise a warning and just ignore it.
+	 */
+
+	if (NULL == r->last) {
+		(*r->msg)(MANDOCERR_NOSCOPE, r->data, ln, ppos, NULL);
+		return(ROFF_IGN);
+	}
+
+	switch (r->last->tok) {
+	case (ROFF_am):
 		/* FALLTHROUGH */
-	case('('):
+	case (ROFF_ami):
 		/* FALLTHROUGH */
-	case(')'):
+	case (ROFF_am1):
 		/* FALLTHROUGH */
-	case('['):
+	case (ROFF_de):
+		/* ROFF_de1 is remapped to ROFF_de in roff_block(). */
 		/* FALLTHROUGH */
-	case(']'):
+	case (ROFF_dei):
 		/* FALLTHROUGH */
-	case('}'):
-		return(1);
-	default:
+	case (ROFF_ig):
 		break;
+	default:
+		(*r->msg)(MANDOCERR_NOSCOPE, r->data, ln, ppos, NULL);
+		return(ROFF_IGN);
 	}
 
-	return(0);
+	if ((*bufp)[pos])
+		(*r->msg)(MANDOCERR_ARGSLOST, r->data, ln, pos, NULL);
+
+	roffnode_pop(r);
+	roffnode_cleanscope(r);
+	return(ROFF_IGN);
+
 }
 
 
-static int
-rofffindcallable(const char *name)
+static void
+roffnode_cleanscope(struct roff *r)
 {
-	int		 c;
 
-	if (ROFF_MAX == (c = rofffindtok(name)))
-		return(ROFF_MAX);
-	assert(c >= 0 && c < ROFF_MAX);
-	return(ROFF_CALLABLE & tokens[c].flags ? c : ROFF_MAX);
+	while (r->last) {
+		if (--r->last->endspan < 0)
+			break;
+		roffnode_pop(r);
+	}
 }
 
 
-static struct roffnode *
-roffnode_new(int tokid, struct rofftree *tree)
+/* ARGSUSED */
+static enum rofferr
+roff_ccond(ROFF_ARGS)
 {
-	struct roffnode	*p;
-	
-	if (NULL == (p = malloc(sizeof(struct roffnode))))
-		err(1, "malloc");
 
-	p->tok = tokid;
-	p->parent = tree->last;
-	tree->last = p;
+	if (NULL == r->last) {
+		(*r->msg)(MANDOCERR_NOSCOPE, r->data, ln, ppos, NULL);
+		return(ROFF_IGN);
+	}
+
+	switch (r->last->tok) {
+	case (ROFF_el):
+		/* FALLTHROUGH */
+	case (ROFF_ie):
+		/* FALLTHROUGH */
+	case (ROFF_if):
+		break;
+	default:
+		(*r->msg)(MANDOCERR_NOSCOPE, r->data, ln, ppos, NULL);
+		return(ROFF_IGN);
+	}
 
-	return(p);
+	if (r->last->endspan > -1) {
+		(*r->msg)(MANDOCERR_NOSCOPE, r->data, ln, ppos, NULL);
+		return(ROFF_IGN);
+	}
+
+	if ((*bufp)[pos])
+		(*r->msg)(MANDOCERR_ARGSLOST, r->data, ln, pos, NULL);
+
+	roffnode_pop(r);
+	roffnode_cleanscope(r);
+	return(ROFF_IGN);
 }
 
 
-static int
-roffargok(int tokid, int argid)
+/* ARGSUSED */
+static enum rofferr
+roff_block(ROFF_ARGS)
 {
-	const int	*c;
+	int		sv;
+	size_t		sz;
+	char		*name;
 
-	if (NULL == (c = tokens[tokid].args))
-		return(0);
+	name = NULL;
 
-	for ( ; ROFF_ARGMAX != *c; c++) 
-		if (argid == *c)
-			return(1);
+	if (ROFF_ig != tok) {
+		if ('\0' == (*bufp)[pos]) {
+			(*r->msg)(MANDOCERR_NOARGS, r->data, ln, ppos, NULL);
+			return(ROFF_IGN);
+		}
 
-	return(0);
-}
+		/*
+		 * Re-write `de1', since we don't really care about
+		 * groff's strange compatibility mode, into `de'.
+		 */
 
+		if (ROFF_de1 == tok)
+			tok = ROFF_de;
+		if (ROFF_de == tok)
+			name = *bufp + pos;
+		else
+			(*r->msg)(MANDOCERR_REQUEST, r->data, ln, ppos,
+			    roffs[tok].name);
 
-static void
-roffnode_free(struct rofftree *tree)
-{
-	struct roffnode	*p;
+		while ((*bufp)[pos] && ' ' != (*bufp)[pos])
+			pos++;
 
-	assert(tree->last);
+		while (' ' == (*bufp)[pos])
+			(*bufp)[pos++] = '\0';
+	}
 
-	p = tree->last;
-	tree->last = tree->last->parent;
-	free(p);
-}
+	roffnode_push(r, tok, name, ln, ppos);
 
+	/*
+	 * At the beginning of a `de' macro, clear the existing string
+	 * with the same name, if there is one.  New content will be
+	 * added from roff_block_text() in multiline mode.
+	 */
 
-static int
-roffnextopt(const struct rofftree *tree, int tok, 
-		char ***in, char **val)
-{
-	char		*arg, **argv;
-	int		 v;
-
-	*val = NULL;
-	argv = *in;
-	assert(argv);
-
-	if (NULL == (arg = *argv))
-		return(-1);
-	if ('-' != *arg)
-		return(-1);
-
-	if (ROFF_ARGMAX == (v = rofffindarg(arg + 1))) {
-		roff_warn(tree, arg, "argument-like parameter `%s' to "
-				"`%s'", &arg[1], toknames[tok]);
-		return(-1);
-	} 
-	
-	if ( ! roffargok(tok, v)) {
-		roff_warn(tree, arg, "invalid argument parameter `%s' to "
-				"`%s'", tokargnames[v], toknames[tok]);
-		return(-1);
-	} 
-	
-	if ( ! (ROFF_VALUE & tokenargs[v]))
-		return(v);
+	if (ROFF_de == tok)
+		roff_setstr(r, name, "", 0);
 
-	*in = ++argv;
+	if ('\0' == (*bufp)[pos])
+		return(ROFF_IGN);
 
-	if (NULL == *argv) {
-		roff_err(tree, arg, "empty value of `%s' for `%s'",
-				tokargnames[v], toknames[tok]);
-		return(ROFF_ARGMAX);
-	}
+	/* If present, process the custom end-of-line marker. */
 
-	return(v);
-}
+	sv = pos;
+	while ((*bufp)[pos] &&
+			' ' != (*bufp)[pos] && 
+			'\t' != (*bufp)[pos])
+		pos++;
 
+	/*
+	 * Note: groff does NOT like escape characters in the input.
+	 * Instead of detecting this, we're just going to let it fly and
+	 * to hell with it.
+	 */
 
-static int
-roffparseopts(struct rofftree *tree, int tok, 
-		char ***args, int *argc, char **argv)
-{
-	int		 i, c;
-	char		*v;
+	assert(pos > sv);
+	sz = (size_t)(pos - sv);
 
-	i = 0;
+	if (1 == sz && '.' == (*bufp)[sv])
+		return(ROFF_IGN);
 
-	while (-1 != (c = roffnextopt(tree, tok, args, &v))) {
-		if (ROFF_ARGMAX == c) 
-			return(0);
+	r->last->end = mandoc_malloc(sz + 1);
 
-		argc[i] = c;
-		argv[i] = v;
-		i++;
-		*args = *args + 1;
-	}
+	memcpy(r->last->end, *bufp + sv, sz);
+	r->last->end[(int)sz] = '\0';
 
-	argc[i] = ROFF_ARGMAX;
-	argv[i] = NULL;
-	return(1);
+	if ((*bufp)[pos])
+		(*r->msg)(MANDOCERR_ARGSLOST, r->data, ln, pos, NULL);
+
+	return(ROFF_IGN);
 }
 
 
 /* ARGSUSED */
-static	int
-roff_Dd(ROFFCALL_ARGS)
+static enum rofferr
+roff_block_sub(ROFF_ARGS)
 {
+	enum rofft	t;
+	int		i, j;
 
-	if (ROFF_BODY & tree->state) {
-		assert( ! (ROFF_PRELUDE & tree->state));
-		assert(ROFF_PRELUDE_Dd & tree->state);
-		return(roff_text(tok, tree, argv, type));
-	}
+	/*
+	 * First check whether a custom macro exists at this level.  If
+	 * it does, then check against it.  This is some of groff's
+	 * stranger behaviours.  If we encountered a custom end-scope
+	 * tag and that tag also happens to be a "real" macro, then we
+	 * need to try interpreting it again as a real macro.  If it's
+	 * not, then return ignore.  Else continue.
+	 */
 
-	assert(ROFF_PRELUDE & tree->state);
-	assert( ! (ROFF_BODY & tree->state));
+	if (r->last->end) {
+		i = pos + 1;
+		while (' ' == (*bufp)[i] || '\t' == (*bufp)[i])
+			i++;
 
-	if (ROFF_PRELUDE_Dd & tree->state) {
-		roff_err(tree, *argv, "repeated `Dd' in prelude");
-		return(0);
-	} else if (ROFF_PRELUDE_Dt & tree->state) {
-		roff_err(tree, *argv, "out-of-order `Dd' in prelude");
-		return(0);
+		for (j = 0; r->last->end[j]; j++, i++)
+			if ((*bufp)[i] != r->last->end[j])
+				break;
+
+		if ('\0' == r->last->end[j] && 
+				('\0' == (*bufp)[i] ||
+				 ' ' == (*bufp)[i] ||
+				 '\t' == (*bufp)[i])) {
+			roffnode_pop(r);
+			roffnode_cleanscope(r);
+
+			if (ROFF_MAX != roff_parse(r, *bufp, &pos))
+				return(ROFF_RERUN);
+			return(ROFF_IGN);
+		}
 	}
 
-	/* TODO: parse date. */
+	/*
+	 * If we have no custom end-query or lookup failed, then try
+	 * pulling it out of the hashtable.
+	 */
 
-	assert(NULL == tree->last);
-	tree->state |= ROFF_PRELUDE_Dd;
+	ppos = pos;
+	t = roff_parse(r, *bufp, &pos);
 
-	return(1);
+	/*
+	 * Macros other than block-end are only significant
+	 * in `de' blocks; elsewhere, simply throw them away.
+	 */
+	if (ROFF_cblock != t) {
+		if (ROFF_de == tok)
+			roff_setstr(r, r->last->name, *bufp + ppos, 1);
+		return(ROFF_IGN);
+	}
+
+	assert(roffs[t].proc);
+	return((*roffs[t].proc)(r, t, bufp, szp, 
+				ln, ppos, pos, offs));
 }
 
 
 /* ARGSUSED */
-static	int
-roff_Dt(ROFFCALL_ARGS)
+static enum rofferr
+roff_block_text(ROFF_ARGS)
 {
 
-	if (ROFF_BODY & tree->state) {
-		assert( ! (ROFF_PRELUDE & tree->state));
-		assert(ROFF_PRELUDE_Dt & tree->state);
-		return(roff_text(tok, tree, argv, type));
-	}
+	if (ROFF_de == tok)
+		roff_setstr(r, r->last->name, *bufp + pos, 1);
 
-	assert(ROFF_PRELUDE & tree->state);
-	assert( ! (ROFF_BODY & tree->state));
+	return(ROFF_IGN);
+}
 
-	if ( ! (ROFF_PRELUDE_Dd & tree->state)) {
-		roff_err(tree, *argv, "out-of-order `Dt' in prelude");
-		return(0);
-	} else if (ROFF_PRELUDE_Dt & tree->state) {
-		roff_err(tree, *argv, "repeated `Dt' in prelude");
-		return(0);
-	}
 
-	/* TODO: parse date. */
+/* ARGSUSED */
+static enum rofferr
+roff_cond_sub(ROFF_ARGS)
+{
+	enum rofft	 t;
+	enum roffrule	 rr;
 
-	assert(NULL == tree->last);
-	tree->state |= ROFF_PRELUDE_Dt;
+	ppos = pos;
+	rr = r->last->rule;
 
-	return(1);
+	/* 
+	 * Clean out scope.  If we've closed ourselves, then don't
+	 * continue. 
+	 */
+
+	roffnode_cleanscope(r);
+
+	if (ROFF_MAX == (t = roff_parse(r, *bufp, &pos))) {
+		if ('\\' == (*bufp)[pos] && '}' == (*bufp)[pos + 1])
+			return(roff_ccond
+				(r, ROFF_ccond, bufp, szp,
+				 ln, pos, pos + 2, offs));
+		return(ROFFRULE_DENY == rr ? ROFF_IGN : ROFF_CONT);
+	}
+
+	/*
+	 * A denied conditional must evaluate its children if and only
+	 * if they're either structurally required (such as loops and
+	 * conditionals) or a closing macro.
+	 */
+	if (ROFFRULE_DENY == rr)
+		if ( ! (ROFFMAC_STRUCT & roffs[t].flags))
+			if (ROFF_ccond != t)
+				return(ROFF_IGN);
+
+	assert(roffs[t].proc);
+	return((*roffs[t].proc)(r, t, bufp, szp, 
+				ln, ppos, pos, offs));
 }
 
 
 /* ARGSUSED */
-static	int
-roff_Os(ROFFCALL_ARGS)
+static enum rofferr
+roff_cond_text(ROFF_ARGS)
 {
+	char		*ep, *st;
+	enum roffrule	 rr;
 
-	if (ROFF_EXIT == type) {
-		return((*tree->cb.rofftail)(tree->arg));
-	} else if (ROFF_BODY & tree->state) {
-		assert( ! (ROFF_PRELUDE & tree->state));
-		assert(ROFF_PRELUDE_Os & tree->state);
-		return(roff_text(tok, tree, argv, type));
-	}
+	rr = r->last->rule;
 
-	assert(ROFF_PRELUDE & tree->state);
-	if ( ! (ROFF_PRELUDE_Dt & tree->state) ||
-			! (ROFF_PRELUDE_Dd & tree->state)) {
-		roff_err(tree, *argv, "out-of-order `Os' in prelude");
-		return(0);
+	/*
+	 * We display the value of the text if out current evaluation
+	 * scope permits us to do so.
+	 */
+
+	/* FIXME: use roff_ccond? */
+
+	st = &(*bufp)[pos];
+	if (NULL == (ep = strstr(st, "\\}"))) {
+		roffnode_cleanscope(r);
+		return(ROFFRULE_DENY == rr ? ROFF_IGN : ROFF_CONT);
 	}
 
-	/* TODO: extract OS. */
+	if (ep == st || (ep > st && '\\' != *(ep - 1)))
+		roffnode_pop(r);
 
-	tree->state |= ROFF_PRELUDE_Os;
-	tree->state &= ~ROFF_PRELUDE;
-	tree->state |= ROFF_BODY;
+	roffnode_cleanscope(r);
+	return(ROFFRULE_DENY == rr ? ROFF_IGN : ROFF_CONT);
+}
 
-	assert(NULL == tree->last);
 
-	return((*tree->cb.roffhead)(tree->arg));
+static enum roffrule
+roff_evalcond(const char *v, int *pos)
+{
+
+	switch (v[*pos]) {
+	case ('n'):
+		(*pos)++;
+		return(ROFFRULE_ALLOW);
+	case ('e'):
+		/* FALLTHROUGH */
+	case ('o'):
+		/* FALLTHROUGH */
+	case ('t'):
+		(*pos)++;
+		return(ROFFRULE_DENY);
+	default:
+		break;
+	}
+
+	while (v[*pos] && ' ' != v[*pos])
+		(*pos)++;
+	return(ROFFRULE_DENY);
 }
 
+/* ARGSUSED */
+static enum rofferr
+roff_line_ignore(ROFF_ARGS)
+{
+
+	if (ROFF_it == tok)
+		(*r->msg)(MANDOCERR_REQUEST, r->data, ln, ppos, "it");
+
+	return(ROFF_IGN);
+}
 
 /* ARGSUSED */
-static int
-roff_layout(ROFFCALL_ARGS) 
+static enum rofferr
+roff_cond(ROFF_ARGS)
 {
-	int		 i, c, argcp[ROFF_MAXARG];
-	char		*argvp[ROFF_MAXARG];
+	int		 sv;
+	enum roffrule	 rule;
 
-	if (ROFF_PRELUDE & tree->state) {
-		roff_err(tree, *argv, "bad `%s' in prelude", 
-				toknames[tok]);
-		return(0);
-	} else if (ROFF_EXIT == type) {
-		roffnode_free(tree);
-		return((*tree->cb.roffblkout)(tree->arg, tok));
-	} 
+	/* Stack overflow! */
 
-	assert( ! (ROFF_CALLABLE & tokens[tok].flags));
+	if (ROFF_ie == tok && r->rstackpos == RSTACK_MAX - 1) {
+		(*r->msg)(MANDOCERR_MEM, r->data, ln, ppos, NULL);
+		return(ROFF_ERR);
+	}
 
-	++argv;
+	/* First, evaluate the conditional. */
 
-	if ( ! roffparseopts(tree, tok, &argv, argcp, argvp))
-		return(0);
-	if (NULL == roffnode_new(tok, tree))
-		return(0);
+	if (ROFF_el == tok) {
+		/* 
+		 * An `.el' will get the value of the current rstack
+		 * entry set in prior `ie' calls or defaults to DENY.
+	 	 */
+		if (r->rstackpos < 0)
+			rule = ROFFRULE_DENY;
+		else
+			rule = r->rstack[r->rstackpos];
+	} else
+		rule = roff_evalcond(*bufp, &pos);
 
-	/*
-	 * Layouts have two parts: the layout body and header.  The
-	 * layout header is the trailing text of the line macro, while
-	 * the layout body is everything following until termination.
-	 */
+	sv = pos;
 
-	if ( ! (*tree->cb.roffblkin)(tree->arg, tok, argcp, argvp))
-		return(0);
-	if (NULL == *argv)
-		return(1);
-	if ( ! (*tree->cb.roffin)(tree->arg, tok, argcp, argvp))
-		return(0);
+	while (' ' == (*bufp)[pos])
+		pos++;
 
 	/*
-	 * If there are no parsable parts, then write remaining tokens
-	 * into the layout header and exit.
+	 * Roff is weird.  If we have just white-space after the
+	 * conditional, it's considered the BODY and we exit without
+	 * really doing anything.  Warn about this.  It's probably
+	 * wrong.
 	 */
 
-	if ( ! (ROFF_PARSED & tokens[tok].flags)) {
-		i = 0;
-		while (*argv) {
-			if ( ! (*tree->cb.roffdata)(tree->arg, i, *argv++))
-				return(0);
-			i = 1;
-		}
-		return((*tree->cb.roffout)(tree->arg, tok));
+	if ('\0' == (*bufp)[pos] && sv != pos) {
+		(*r->msg)(MANDOCERR_NOARGS, r->data, ln, ppos, NULL);
+		return(ROFF_IGN);
 	}
 
+	roffnode_push(r, tok, NULL, ln, ppos);
+
+	r->last->rule = rule;
+
+	if (ROFF_ie == tok) {
+		/*
+		 * An if-else will put the NEGATION of the current
+		 * evaluated conditional into the stack.
+		 */
+		r->rstackpos++;
+		if (ROFFRULE_DENY == r->last->rule)
+			r->rstack[r->rstackpos] = ROFFRULE_ALLOW;
+		else
+			r->rstack[r->rstackpos] = ROFFRULE_DENY;
+	}
+
+	/* If the parent has false as its rule, then so do we. */
+
+	if (r->last->parent && ROFFRULE_DENY == r->last->parent->rule)
+		r->last->rule = ROFFRULE_DENY;
+
 	/*
-	 * Parsable elements may be in the header (or be the header, for
-	 * that matter).  Follow the regular parsing rules for these.
+	 * Determine scope.  If we're invoked with "\{" trailing the
+	 * conditional, then we're in a multiline scope.  Else our scope
+	 * expires on the next line.
 	 */
 
-	i = 0;
-	while (*argv) {
-		if (ROFF_MAX == (c = rofffindcallable(*argv))) {
-			assert(tree->arg);
-			if ( ! (*tree->cb.roffdata)
-					(tree->arg, i, *argv++))
-				return(0);
-			i = 1;
-			continue;
-		}
+	r->last->endspan = 1;
 
-		if (NULL == tokens[c].cb) {
-			roff_err(tree, *argv, "unsupported macro `%s'",
-					toknames[c]);
-			return(0);
-		}
+	if ('\\' == (*bufp)[pos] && '{' == (*bufp)[pos + 1]) {
+		r->last->endspan = -1;
+		pos += 2;
+	} 
+
+	/*
+	 * If there are no arguments on the line, the next-line scope is
+	 * assumed.
+	 */
 
-		if ( ! (*tokens[c].cb)(c, tree, argv, ROFF_ENTER))
-			return(0);
+	if ('\0' == (*bufp)[pos])
+		return(ROFF_IGN);
 
-		break;
-	}
+	/* Otherwise re-run the roff parser after recalculating. */
+
+	*offs = pos;
+	return(ROFF_RERUN);
+}
 
-	/* 
-	 * If there's trailing punctuation in the header, then write it
-	 * out now.  Here we mimic the behaviour of a line-dominant text
-	 * macro.
-	 */
 
-	if (NULL == *argv)
-		return((*tree->cb.roffout)(tree->arg, tok));
+/* ARGSUSED */
+static enum rofferr
+roff_ds(ROFF_ARGS)
+{
+	char		*name, *string;
 
 	/*
-	 * Expensive.  Scan to the end of line then work backwards until
-	 * a token isn't punctuation.
+	 * A symbol is named by the first word following the macro
+	 * invocation up to a space.  Its value is anything after the
+	 * name's trailing whitespace and optional double-quote.  Thus,
+	 *
+	 *  [.ds foo "bar  "     ]
+	 *
+	 * will have `bar  "     ' as its value.
 	 */
 
-	i = 0;
-	while (argv[i])
-		i++;
+	string = *bufp + pos;
+	name = roff_getname(r, &string, ln, pos);
+	if ('\0' == *name)
+		return(ROFF_IGN);
+
+	/* Read past initial double-quote. */
+	if ('"' == *string)
+		string++;
+
+	/* The rest is the value. */
+	roff_setstr(r, name, string, 0);
+	return(ROFF_IGN);
+}
 
-	assert(i > 0);
-	if ( ! roffispunct(argv[--i]))
-		return((*tree->cb.roffout)(tree->arg, tok));
 
-	while (i >= 0 && roffispunct(argv[i]))
-		i--;
+/* ARGSUSED */
+static enum rofferr
+roff_nr(ROFF_ARGS)
+{
+	const char	*key;
+	char		*val;
+	struct reg	*rg;
+
+	val = *bufp + pos;
+	key = roff_getname(r, &val, ln, pos);
+	rg = r->regs->regs;
+
+	if (0 == strcmp(key, "nS")) {
+		rg[(int)REG_nS].set = 1;
+		if ( ! roff_parse_nat(val, &rg[(int)REG_nS].v.u))
+			rg[(int)REG_nS].v.u = 0;
+	}
 
-	assert(0 != i);
-	i++;
+	return(ROFF_IGN);
+}
+
+/* ARGSUSED */
+static enum rofferr
+roff_rm(ROFF_ARGS)
+{
+	const char	 *name;
+	char		 *cp;
+
+	cp = *bufp + pos;
+	while ('\0' != *cp) {
+		name = roff_getname(r, &cp, ln, cp - *bufp);
+		if ('\0' != *name)
+			roff_setstr(r, name, NULL, 0);
+	}
+	return(ROFF_IGN);
+}
+
+/* ARGSUSED */
+static enum rofferr
+roff_TE(ROFF_ARGS)
+{
 
-	/* LINTED */
-	while (argv[i])
-		if ( ! (*tree->cb.roffdata)(tree->arg, 0, argv[i++]))
-			return(0);
+	if (NULL == r->tbl)
+		(*r->msg)(MANDOCERR_NOSCOPE, r->data, ln, ppos, NULL);
+	else
+		tbl_end(r->tbl);
 
-	return((*tree->cb.roffout)(tree->arg, tok));
+	r->tbl = NULL;
+	return(ROFF_IGN);
 }
 
+/* ARGSUSED */
+static enum rofferr
+roff_T_(ROFF_ARGS)
+{
+
+	if (NULL == r->tbl)
+		(*r->msg)(MANDOCERR_NOSCOPE, r->data, ln, ppos, NULL);
+	else
+		tbl_restart(ppos, ln, r->tbl);
+
+	return(ROFF_IGN);
+}
 
 /* ARGSUSED */
-static int
-roff_text(ROFFCALL_ARGS) 
+static enum rofferr
+roff_EQ(ROFF_ARGS)
 {
-	int		 i, j, first, c, argcp[ROFF_MAXARG];
-	char		*argvp[ROFF_MAXARG];
+	struct eqn_node	*e;
 
-	if (ROFF_PRELUDE & tree->state) {
-		roff_err(tree, *argv, "`%s' disallowed in prelude", 
-				toknames[tok]);
-		return(0);
+	assert(NULL == r->eqn);
+	e = eqn_alloc(ppos, ln);
+
+	if (r->last_eqn)
+		r->last_eqn->next = e;
+	else
+		r->first_eqn = r->last_eqn = e;
+
+	r->eqn = r->last_eqn = e;
+	return(ROFF_IGN);
+}
+
+/* ARGSUSED */
+static enum rofferr
+roff_EN(ROFF_ARGS)
+{
+
+	(*r->msg)(MANDOCERR_NOSCOPE, r->data, ln, ppos, NULL);
+	return(ROFF_IGN);
+}
+
+/* ARGSUSED */
+static enum rofferr
+roff_TS(ROFF_ARGS)
+{
+	struct tbl_node	*t;
+
+	if (r->tbl) {
+		(*r->msg)(MANDOCERR_SCOPEBROKEN, r->data, ln, ppos, NULL);
+		tbl_end(r->tbl);
 	}
 
-	first = (*argv == tree->cur);
-	argv++;
+	t = tbl_alloc(ppos, ln, r->data, r->msg);
 
-	if ( ! roffparseopts(tree, tok, &argv, argcp, argvp))
-		return(0);
-	if ( ! (*tree->cb.roffin)(tree->arg, tok, argcp, argvp))
-		return(0);
-	if (NULL == *argv)
-		return((*tree->cb.roffout)(tree->arg, tok));
-
-	if ( ! (ROFF_PARSED & tokens[tok].flags)) {
-		i = 0;
-		while (*argv) {
-			if ( ! (*tree->cb.roffdata)(tree->arg, i, *argv++))
-				return(0);
-			i = 1;
-		}
-		return((*tree->cb.roffout)(tree->arg, tok));
+	if (r->last_tbl)
+		r->last_tbl->next = t;
+	else
+		r->first_tbl = r->last_tbl = t;
+
+	r->tbl = r->last_tbl = t;
+	return(ROFF_IGN);
+}
+
+/* ARGSUSED */
+static enum rofferr
+roff_so(ROFF_ARGS)
+{
+	char *name;
+
+	(*r->msg)(MANDOCERR_SO, r->data, ln, ppos, NULL);
+
+	/*
+	 * Handle `so'.  Be EXTREMELY careful, as we shouldn't be
+	 * opening anything that's not in our cwd or anything beneath
+	 * it.  Thus, explicitly disallow traversing up the file-system
+	 * or using absolute paths.
+	 */
+
+	name = *bufp + pos;
+	if ('/' == *name || strstr(name, "../") || strstr(name, "/..")) {
+		(*r->msg)(MANDOCERR_SOPATH, r->data, ln, pos, NULL);
+		return(ROFF_ERR);
 	}
 
+	*offs = pos;
+	return(ROFF_SO);
+}
+
+/* ARGSUSED */
+static enum rofferr
+roff_userdef(ROFF_ARGS)
+{
+	const char	 *arg[9];
+	char		 *cp, *n1, *n2;
+	int		  i;
+
 	/*
-	 * Deal with punctuation.  Ugly.  Work ahead until we encounter
-	 * terminating punctuation.  If we encounter it and all
-	 * subsequent tokens are punctuation, then stop processing (the
-	 * line-dominant macro will print these tokens after closure).
+	 * Collect pointers to macro argument strings
+	 * and null-terminate them.
 	 */
+	cp = *bufp + pos;
+	for (i = 0; i < 9; i++)
+		arg[i] = '\0' == *cp ? "" :
+		    mandoc_getarg(&cp, r->msg, r->data, ln, &pos);
 
-	i = 0;
-	while (*argv) {
-		if (ROFF_MAX == (c = rofffindcallable(*argv))) {
-			if ( ! roffispunct(*argv)) {
-				if ( ! (*tree->cb.roffdata)
-						(tree->arg, i, *argv++))
-					return(0);
-				i = 1;
-				continue;
-			}
-
-			/* See if only punctuation remains. */
-
-			i = 1;
-			for (j = 0; argv[j]; j++)
-				if ( ! roffispunct(argv[j]))
-					break;
-
-			if (argv[j]) {
-				if ( ! (*tree->cb.roffdata)
-						(tree->arg, 0, *argv++))
-					return(0);
-				continue;
-			}
-
-			/*  Only punctuation remains. */
-
-			if ( ! (*tree->cb.roffout)(tree->arg, tok))
-				return(0);
-			break;
+	/*
+	 * Expand macro arguments.
+	 */
+	*szp = 0;
+	n1 = cp = mandoc_strdup(r->current_string);
+	while (NULL != (cp = strstr(cp, "\\$"))) {
+		i = cp[2] - '1';
+		if (0 > i || 8 < i) {
+			/* Not an argument invocation. */
+			cp += 2;
+			continue;
 		}
 
-		/*
-		 * A sub-command has been found.  Execute it and
-		 * discontinue parsing for arguments.  If we're
-		 * line-scoped, then close out after it returns; if we
-		 * aren't, then close out before.
-		 */
+		*szp = strlen(n1) - 3 + strlen(arg[i]) + 1;
+		n2 = mandoc_malloc(*szp);
 
-		if (NULL == tokens[c].cb) {
-			roff_err(tree, *argv, "unsupported macro `%s'",
-					toknames[c]);
-			return(0);
-		} 
-		
-		if ( ! (ROFF_LSCOPE & tokens[tok].flags))
-			if ( ! (*tree->cb.roffout)(tree->arg, tok))
-				return(0);
-		
-		if ( ! (*tokens[c].cb)(c, tree, argv, ROFF_ENTER))
-			return(0);
-
-		if (ROFF_LSCOPE & tokens[tok].flags)
-			if ( ! (*tree->cb.roffout)(tree->arg, tok))
-				return(0);
+		strlcpy(n2, n1, (size_t)(cp - n1 + 1));
+		strlcat(n2, arg[i], *szp);
+		strlcat(n2, cp + 3, *szp);
 
-		break;
+		cp = n2 + (cp - n1);
+		free(n1);
+		n1 = n2;
 	}
 
-	if (NULL == *argv)
-		return((*tree->cb.roffout)(tree->arg, tok));
-	if ( ! first)
-		return(1);
-
 	/*
-	 * We're the line-dominant macro.  Check if there's remaining
-	 * punctuation.  If there is, then flush it out before exiting.
+	 * Replace the macro invocation
+	 * by the expanded macro.
 	 */
+	free(*bufp);
+	*bufp = n1;
+	if (0 == *szp)
+		*szp = strlen(*bufp) + 1;
 
-	i = 0;
-	while (argv[i])
-		i++;
+	return(*szp > 1 && '\n' == (*bufp)[(int)*szp - 2] ?
+	   ROFF_REPARSE : ROFF_APPEND);
+}
 
-	assert(i > 0);
-	if ( ! roffispunct(argv[--i]))
-		return(1);
+static char *
+roff_getname(struct roff *r, char **cpp, int ln, int pos)
+{
+	char	 *name, *cp;
 
-	while (i >= 0 && roffispunct(argv[i]))
-		i--;
+	name = *cpp;
+	if ('\0' == *name)
+		return(name);
 
-	assert(0 != i);
-	i++;
+	/* Read until end of name. */
+	for (cp = name; '\0' != *cp && ' ' != *cp; cp++) {
+		if ('\\' != *cp)
+			continue;
+		cp++;
+		if ('\\' == *cp)
+			continue;
+		(*r->msg)(MANDOCERR_NAMESC, r->data, ln, pos, NULL);
+		*cp = '\0';
+		name = cp;
+	}
 
-	/* LINTED */
-	while (argv[i])
-		if ( ! (*tree->cb.roffdata)(tree->arg, 0, argv[i++]))
-			return(0);
+	/* Nil-terminate name. */
+	if ('\0' != *cp)
+		*(cp++) = '\0';
 
-	return(1);
-}
+	/* Read past spaces. */
+	while (' ' == *cp)
+		cp++;
 
+	*cpp = cp;
+	return(name);
+}
 
-/* ARGSUSED */
-static int
-roff_noop(ROFFCALL_ARGS)
+/*
+ * Store *string into the user-defined string called *name.
+ * In multiline mode, append to an existing entry and append '\n';
+ * else replace the existing entry, if there is one.
+ * To clear an existing entry, call with (*r, *name, NULL, 0).
+ */
+static void
+roff_setstr(struct roff *r, const char *name, const char *string,
+	int multiline)
 {
+	struct roffstr	 *n;
+	char		 *c;
+	size_t		  oldch, newch;
 
-	return(1);
-}
+	/* Search for an existing string with the same name. */
+	n = r->first_string;
+	while (n && strcmp(name, n->name))
+		n = n->next;
 
+	if (NULL == n) {
+		/* Create a new string table entry. */
+		n = mandoc_malloc(sizeof(struct roffstr));
+		n->name = mandoc_strdup(name);
+		n->string = NULL;
+		n->next = r->first_string;
+		r->first_string = n;
+	} else if (0 == multiline) {
+		/* In multiline mode, append; else replace. */
+		free(n->string);
+		n->string = NULL;
+	}
 
-/* ARGSUSED */
-static int
-roff_depr(ROFFCALL_ARGS)
-{
+	if (NULL == string)
+		return;
 
-	roff_err(tree, *argv, "`%s' is deprecated", toknames[tok]);
-	return(0);
-}
+	/*
+	 * One additional byte for the '\n' in multiline mode,
+	 * and one for the terminating '\0'.
+	 */
+	newch = strlen(string) + (multiline ? 2 : 1);
+	if (NULL == n->string) {
+		n->string = mandoc_malloc(newch);
+		*n->string = '\0';
+		oldch = 0;
+	} else {
+		oldch = strlen(n->string);
+		n->string = mandoc_realloc(n->string, oldch + newch);
+	}
 
+	/* Skip existing content in the destination buffer. */
+	c = n->string + oldch;
 
-static void
-roff_warn(const struct rofftree *tree, const char *pos, char *fmt, ...)
+	/* Append new content to the destination buffer. */
+	while (*string) {
+		/*
+		 * Rudimentary roff copy mode:
+		 * Handle escaped backslashes.
+		 */
+		if ('\\' == *string && '\\' == *(string + 1))
+			string++;
+		*c++ = *string++;
+	}
+
+	/* Append terminating bytes. */
+	if (multiline)
+		*c++ = '\n';
+	*c = '\0';
+}
+
+static const char *
+roff_getstrn(const struct roff *r, const char *name, size_t len)
 {
-	va_list		 ap;
-	char		 buf[128];
+	const struct roffstr *n;
 
-	va_start(ap, fmt);
-	(void)vsnprintf(buf, sizeof(buf), fmt, ap);
-	va_end(ap);
+	n = r->first_string;
+	while (n && (strncmp(name, n->name, len) || '\0' != n->name[(int)len]))
+		n = n->next;
 
-	(*tree->cb.roffmsg)(tree->arg, 
-			ROFF_WARN, tree->cur, pos, buf);
+	return(n ? n->string : NULL);
 }
 
-
 static void
-roff_err(const struct rofftree *tree, const char *pos, char *fmt, ...)
+roff_freestr(struct roff *r)
 {
-	va_list		 ap;
-	char		 buf[128];
+	struct roffstr	 *n, *nn;
+
+	for (n = r->first_string; n; n = nn) {
+		free(n->name);
+		free(n->string);
+		nn = n->next;
+		free(n);
+	}
+
+	r->first_string = NULL;
+}
 
-	va_start(ap, fmt);
-	(void)vsnprintf(buf, sizeof(buf), fmt, ap);
-	va_end(ap);
+const struct tbl_span *
+roff_span(const struct roff *r)
+{
+	
+	return(r->tbl ? tbl_span(r->tbl) : NULL);
+}
 
-	(*tree->cb.roffmsg)(tree->arg, 
-			ROFF_ERROR, tree->cur, pos, buf);
+const struct eqn *
+roff_eqn(const struct roff *r)
+{
+	
+	return(r->last_eqn ? &r->last_eqn->eqn : NULL);
 }