X-Git-Url: https://git.cameronkatri.com/mandoc.git/blobdiff_plain/571f65402c81aa8dc9d599fb5deab2af8cd3f1c0..27f8e84915215c0597fefa5f2ed7ce6e0e0cb824:/roff.c

diff --git a/roff.c b/roff.c
index 8ec71ad7..c42643cc 100644
--- a/roff.c
+++ b/roff.c
@@ -1,14 +1,15 @@
-/*	$Id: roff.c,v 1.85 2010/05/29 19:41:47 kristaps Exp $ */
+/*	$Id: roff.c,v 1.108 2010/12/21 01:46:44 schwarze Exp $ */
 /*
  * Copyright (c) 2010 Kristaps Dzonsons <kristaps@bsd.lv>
+ * Copyright (c) 2010 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.
  *
- * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * 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 AUTHOR BE LIABLE FOR
+ * 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
@@ -19,20 +20,32 @@
 #endif
 
 #include <assert.h>
+#include <errno.h>
 #include <ctype.h>
+#include <limits.h>
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>
 
 #include "mandoc.h"
 #include "roff.h"
+#include "libmandoc.h"
 
 #define	RSTACK_MAX	128
 
 #define	ROFF_CTL(c) \
 	('.' == (c) || '\'' == (c))
 
+#if 1
+#define	ROFF_DEBUG(fmt, args...) \
+	do { /* Nothing. */ } while (/*CONSTCOND*/ 0)
+#else
+#define	ROFF_DEBUG(fmt, args...) \
+	do { fprintf(stderr, fmt , ##args); } while (/*CONSTCOND*/ 0)
+#endif
+
 enum	rofft {
+	ROFF_ad,
 	ROFF_am,
 	ROFF_ami,
 	ROFF_am1,
@@ -41,13 +54,19 @@ enum	rofft {
 	ROFF_de1,
 	ROFF_ds,
 	ROFF_el,
+	ROFF_hy,
 	ROFF_ie,
 	ROFF_if,
 	ROFF_ig,
+	ROFF_ne,
+	ROFF_nh,
+	ROFF_nr,
 	ROFF_rm,
+	ROFF_so,
 	ROFF_tr,
 	ROFF_cblock,
-	ROFF_ccond,
+	ROFF_ccond, /* FIXME: remove this. */
+	ROFF_USERDEF,
 	ROFF_MAX
 };
 
@@ -56,12 +75,22 @@ enum	roffrule {
 	ROFFRULE_DENY
 };
 
+
+struct	roffstr {
+	char		*name; /* key of symbol */
+	char		*string; /* current value */
+	struct roffstr	*next; /* next in list */
+};
+
 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	roffnode {
@@ -69,6 +98,7 @@ struct	roffnode {
 	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 */
@@ -103,7 +133,20 @@ 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_line(ROFF_ARGS);
+static	enum rofferr	 roff_ds(ROFF_ARGS);
+static	enum roffrule	 roff_evalcond(const char *, int *);
+static	void		 roff_freestr(struct roff *);
+static	const char	*roff_getstrn(const struct roff *, 
+				const char *, size_t);
+static	enum rofferr	 roff_line_ignore(ROFF_ARGS);
+static	enum rofferr	 roff_line_error(ROFF_ARGS);
+static	enum rofferr	 roff_nr(ROFF_ARGS);
+static	int		 roff_res(struct roff *, 
+				char **, size_t *, int);
+static	void		 roff_setstr(struct roff *,
+				const char *, const char *, int);
+static	enum rofferr	 roff_so(ROFF_ARGS);
+static	enum rofferr	 roff_userdef(ROFF_ARGS);
 
 /* See roff_hash_find() */
 
@@ -114,31 +157,39 @@ static	enum rofferr	 roff_line(ROFF_ARGS);
 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_line, NULL, NULL, 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 },
-	{ "rm", roff_line, NULL, NULL, 0, NULL },
-	{ "tr", roff_line, 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 },
+	{ "rm", roff_line_error, NULL, NULL, 0, NULL },
+	{ "so", roff_so, NULL, NULL, 0, NULL },
+	{ "tr", roff_line_ignore, NULL, NULL, 0, NULL },
 	{ ".", roff_cblock, NULL, NULL, 0, NULL },
 	{ "\\}", roff_ccond, NULL, NULL, 0, NULL },
+	{ NULL, roff_userdef, NULL, NULL, 0, NULL },
 };
 
 static	void		 roff_free1(struct roff *);
-static	enum rofft	 roff_hash_find(const char *);
+static	enum rofft	 roff_hash_find(const char *, size_t);
 static	void		 roff_hash_init(void);
 static	void		 roffnode_cleanscope(struct roff *);
-static	int		 roffnode_push(struct roff *, 
-				enum rofft, int, int);
+static	void		 roffnode_push(struct roff *, enum rofft,
+				const char *, int, int);
 static	void		 roffnode_pop(struct roff *);
-static	enum rofft	 roff_parse(const char *, int *);
+static	enum rofft	 roff_parse(struct roff *, const char *, int *);
+static	int		 roff_parse_nat(const char *, unsigned int *);
 
 /* See roff_hash_find() */
 #define	ROFF_HASH(p)	(p[0] - ASCII_LO)
@@ -149,7 +200,7 @@ roff_hash_init(void)
 	struct roffmac	 *n;
 	int		  buc, i;
 
-	for (i = 0; i < (int)ROFF_MAX; i++) {
+	for (i = 0; i < (int)ROFF_USERDEF; i++) {
 		assert(roffs[i].name[0] >= ASCII_LO);
 		assert(roffs[i].name[0] <= ASCII_HI);
 
@@ -170,7 +221,7 @@ roff_hash_init(void)
  * the nil-terminated string name could be found.
  */
 static enum rofft
-roff_hash_find(const char *p)
+roff_hash_find(const char *p, size_t s)
 {
 	int		 buc;
 	struct roffmac	*n;
@@ -190,7 +241,7 @@ roff_hash_find(const char *p)
 	if (NULL == (n = hash[buc]))
 		return(ROFF_MAX);
 	for ( ; n; n = n->next)
-		if (0 == strcmp(n->name, p))
+		if (0 == strncmp(n->name, p, s) && '\0' == n->name[(int)s])
 			return((enum rofft)(n - roffs));
 
 	return(ROFF_MAX);
@@ -213,9 +264,10 @@ roffnode_pop(struct roff *r)
 		if (r->rstackpos > -1)
 			r->rstackpos--;
 
+	ROFF_DEBUG("roff: popping scope\n");
 	r->last = r->last->parent;
-	if (p->end)
-		free(p->end);
+	free(p->name);
+	free(p->end);
 	free(p);
 }
 
@@ -224,24 +276,22 @@ roffnode_pop(struct roff *r)
  * Push a roff node onto the instruction stack.  This must later be
  * removed with roffnode_pop().
  */
-static int
-roffnode_push(struct roff *r, enum rofft tok, int line, int col)
+static void
+roffnode_push(struct roff *r, enum rofft tok, const char *name,
+		int line, int col)
 {
 	struct roffnode	*p;
 
-	if (NULL == (p = calloc(1, sizeof(struct roffnode)))) {
-		(*r->msg)(MANDOCERR_MEM, r->data, line, col, NULL);
-		return(0);
-	}
-
+	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;
 
 	r->last = p;
-	return(1);
 }
 
 
@@ -251,6 +301,7 @@ roff_free1(struct roff *r)
 
 	while (r->last)
 		roffnode_pop(r);
+	roff_freestr(r);
 }
 
 
@@ -272,15 +323,12 @@ roff_free(struct roff *r)
 
 
 struct roff *
-roff_alloc(const mandocmsg msg, void *data)
+roff_alloc(struct regset *regs, void *data, const mandocmsg msg)
 {
 	struct roff	*r;
 
-	if (NULL == (r = calloc(1, sizeof(struct roff)))) {
-		(*msg)(MANDOCERR_MEM, data, 0, 0, NULL);
-		return(0);
-	}
-
+	r = mandoc_calloc(1, sizeof(struct roff));
+	r->regs = regs;
 	r->msg = msg;
 	r->data = data;
 	r->rstackpos = -1;
@@ -290,13 +338,120 @@ roff_alloc(const mandocmsg msg, void *data)
 }
 
 
+/*
+ * 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;
+
+	/* Search for a leading backslash and save a pointer to it. */
+
+	cp = *bufp + pos;
+	while (NULL != (cp = strchr(cp, '\\'))) {
+		stesc = cp++;
+
+		/*
+		 * 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.
+		 */
+
+		if ('\0' == *cp)
+			return(1);
+		if ('*' != *cp++)
+			continue;
+
+		/*
+		 * The third character decides the length
+		 * of the name of the string.
+		 * Save a pointer to the name.
+		 */
+
+		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;
+		}
+
+		/*
+		 * Retrieve the replacement string; if it is
+		 * undefined, resume searching for escapes.
+		 */
+
+		res = roff_getstrn(r, stnam, (size_t)i);
+
+		if (NULL == res) {
+			cp -= maxl ? 1 : 0;
+			continue;
+		}
+
+		/* Replace the escape sequence by the string. */
+
+		ROFF_DEBUG("roff: splicing reserved: [%.*s]\n", i, st);
+
+		nsz = *szp + strlen(res) + 1;
+		n = mandoc_malloc(nsz);
+
+		strlcpy(n, *bufp, (size_t)(stesc - *bufp + 1));
+		strlcat(n, res, nsz);
+		strlcat(n, cp + (maxl ? 0 : 1), nsz);
+
+		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)
+roff_parseln(struct roff *r, int ln, char **bufp, 
+		size_t *szp, int pos, int *offs)
 {
 	enum rofft	 t;
 	int		 ppos;
 
+	/*
+	 * Run the reserved-word filter only if we have some reserved
+	 * words to fill in.
+	 */
+
+	if (r->first_string && ! roff_res(r, bufp, szp, pos))
+		return(ROFF_REPARSE);
+
 	/*
 	 * 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
@@ -306,8 +461,11 @@ roff_parseln(struct roff *r, int ln,
 	if (r->last && ! ROFF_CTL((*bufp)[pos])) {
 		t = r->last->tok;
 		assert(roffs[t].text);
+		ROFF_DEBUG("roff: intercept scoped text: %s, [%s]\n", 
+				roffs[t].name, &(*bufp)[pos]);
 		return((*roffs[t].text)
-				(r, t, bufp, szp, ln, pos, pos, offs));
+				(r, t, bufp, szp, 
+				 ln, pos, pos, offs));
 	} else if ( ! ROFF_CTL((*bufp)[pos]))
 		return(ROFF_CONT);
 
@@ -319,8 +477,11 @@ roff_parseln(struct roff *r, int ln,
 	if (r->last) {
 		t = r->last->tok;
 		assert(roffs[t].sub);
+		ROFF_DEBUG("roff: intercept scoped context: %s, [%s]\n", 
+				roffs[t].name, &(*bufp)[pos]);
 		return((*roffs[t].sub)
-				(r, t, bufp, szp, ln, pos, pos, offs));
+				(r, t, bufp, szp, 
+				 ln, pos, pos, offs));
 	}
 
 	/*
@@ -330,12 +491,17 @@ roff_parseln(struct roff *r, int ln,
 	 */
 
 	ppos = pos;
-	if (ROFF_MAX == (t = roff_parse(*bufp, &pos)))
+	if (ROFF_MAX == (t = roff_parse(r, *bufp, &pos)))
 		return(ROFF_CONT);
 
+	ROFF_DEBUG("roff: intercept new-scope: [%s], [%s]\n", 
+			ROFF_USERDEF == t ? r->current_string : roffs[t].name, 
+			&(*bufp)[pos]);
+
 	assert(roffs[t].proc);
 	return((*roffs[t].proc)
-			(r, t, bufp, szp, ln, ppos, pos, offs));
+			(r, t, bufp, szp, 
+			 ln, ppos, pos, offs));
 }
 
 
@@ -355,35 +521,28 @@ roff_endparse(struct roff *r)
  * form of ".foo xxx" in the usual way.
  */
 static enum rofft
-roff_parse(const char *buf, int *pos)
+roff_parse(struct roff *r, const char *buf, int *pos)
 {
-	int		 j;
-	char		 mac[5];
+	const char	*mac;
+	size_t		 maclen;
 	enum rofft	 t;
 
 	assert(ROFF_CTL(buf[*pos]));
 	(*pos)++;
 
-	while (buf[*pos] && (' ' == buf[*pos] || '\t' == buf[*pos]))
+	while (' ' == buf[*pos] || '\t' == buf[*pos])
 		(*pos)++;
 
 	if ('\0' == buf[*pos])
 		return(ROFF_MAX);
 
-	for (j = 0; j < 4; j++, (*pos)++)
-		if ('\0' == (mac[j] = buf[*pos]))
-			break;
-		else if (' ' == buf[*pos] || (j && '\\' == buf[*pos]))
-			break;
-
-	if (j == 4 || j < 1)
-		return(ROFF_MAX);
-
-	mac[j] = '\0';
+	mac = buf + *pos;
+	maclen = strcspn(mac, " \\\t\0");
 
-	if (ROFF_MAX == (t = roff_hash_find(mac)))
-		return(t);
+	t = (r->current_string = roff_getstrn(r, mac, maclen))
+	    ? ROFF_USERDEF : roff_hash_find(mac, maclen);
 
+	*pos += maclen;
 	while (buf[*pos] && ' ' == buf[*pos])
 		(*pos)++;
 
@@ -391,6 +550,26 @@ roff_parse(const char *buf, int *pos)
 }
 
 
+static int
+roff_parse_nat(const char *buf, unsigned int *res)
+{
+	char		*ep;
+	long		 lval;
+
+	errno = 0;
+	lval = strtol(buf, &ep, 10);
+	if (buf[0] == '\0' || *ep != '\0')
+		return(0);
+	if ((errno == ERANGE && 
+			(lval == LONG_MAX || lval == LONG_MIN)) ||
+			(lval > INT_MAX || lval < 0))
+		return(0);
+
+	*res = (unsigned int)lval;
+	return(1);
+}
+
+
 /* ARGSUSED */
 static enum rofferr
 roff_cblock(ROFF_ARGS)
@@ -415,11 +594,10 @@ roff_cblock(ROFF_ARGS)
 	case (ROFF_am1):
 		/* FALLTHROUGH */
 	case (ROFF_de):
+		/* ROFF_de1 is remapped to ROFF_de in roff_block(). */
 		/* FALLTHROUGH */
 	case (ROFF_dei):
 		/* FALLTHROUGH */
-	case (ROFF_de1):
-		/* FALLTHROUGH */
 	case (ROFF_ig):
 		break;
 	default:
@@ -497,26 +675,55 @@ roff_block(ROFF_ARGS)
 {
 	int		sv;
 	size_t		sz;
+	char		*name;
+
+	name = NULL;
+
+	if (ROFF_ig != tok) {
+		if ('\0' == (*bufp)[pos]) {
+			(*r->msg)(MANDOCERR_NOARGS, r->data, ln, ppos, NULL);
+			return(ROFF_IGN);
+		}
+
+		/*
+		 * 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);
 
-	if (ROFF_ig != tok && '\0' == (*bufp)[pos]) {
-		if ( ! (*r->msg)(MANDOCERR_NOARGS, r->data, ln, ppos, NULL))
-			return(ROFF_ERR);
-		return(ROFF_IGN);
-	} else if (ROFF_ig != tok) {
 		while ((*bufp)[pos] && ' ' != (*bufp)[pos])
 			pos++;
+
 		while (' ' == (*bufp)[pos])
-			pos++;
+			(*bufp)[pos++] = '\0';
 	}
 
-	if ( ! roffnode_push(r, tok, ln, ppos))
-		return(ROFF_ERR);
+	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.
+	 */
+
+	if (ROFF_de == tok)
+		roff_setstr(r, name, "", 0);
 
 	if ('\0' == (*bufp)[pos])
 		return(ROFF_IGN);
 
+	/* If present, process the custom end-of-line marker. */
+
 	sv = pos;
-	while ((*bufp)[pos] && ' ' != (*bufp)[pos] && 
+	while ((*bufp)[pos] &&
+			' ' != (*bufp)[pos] && 
 			'\t' != (*bufp)[pos])
 		pos++;
 
@@ -532,19 +739,13 @@ roff_block(ROFF_ARGS)
 	if (1 == sz && '.' == (*bufp)[sv])
 		return(ROFF_IGN);
 
-	r->last->end = malloc(sz + 1);
-
-	if (NULL == r->last->end) {
-		(*r->msg)(MANDOCERR_MEM, r->data, ln, pos, NULL);
-		return(ROFF_ERR);
-	}
+	r->last->end = mandoc_malloc(sz + 1);
 
 	memcpy(r->last->end, *bufp + sv, sz);
 	r->last->end[(int)sz] = '\0';
 
 	if ((*bufp)[pos])
-		if ( ! (*r->msg)(MANDOCERR_ARGSLOST, r->data, ln, pos, NULL))
-			return(ROFF_ERR);
+		(*r->msg)(MANDOCERR_ARGSLOST, r->data, ln, pos, NULL);
 
 	return(ROFF_IGN);
 }
@@ -582,7 +783,7 @@ roff_block_sub(ROFF_ARGS)
 			roffnode_pop(r);
 			roffnode_cleanscope(r);
 
-			if (ROFF_MAX != roff_parse(*bufp, &pos))
+			if (ROFF_MAX != roff_parse(r, *bufp, &pos))
 				return(ROFF_RERUN);
 			return(ROFF_IGN);
 		}
@@ -594,15 +795,21 @@ roff_block_sub(ROFF_ARGS)
 	 */
 
 	ppos = pos;
-	t = roff_parse(*bufp, &pos);
+	t = roff_parse(r, *bufp, &pos);
 
-	/* If we're not a comment-end, then throw it away. */
-	if (ROFF_cblock != t)
+	/*
+	 * 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));
+	return((*roffs[t].proc)(r, t, bufp, szp, 
+				ln, ppos, pos, offs));
 }
 
 
@@ -611,6 +818,9 @@ static enum rofferr
 roff_block_text(ROFF_ARGS)
 {
 
+	if (ROFF_de == tok)
+		roff_setstr(r, r->last->name, *bufp + pos, 1);
+
 	return(ROFF_IGN);
 }
 
@@ -625,10 +835,20 @@ roff_cond_sub(ROFF_ARGS)
 	ppos = pos;
 	rr = r->last->rule;
 
-	roff_cond_text(r, tok, bufp, szp, ln, ppos, pos, offs);
+	/* 
+	 * Clean out scope.  If we've closed ourselves, then don't
+	 * continue. 
+	 */
 
-	if (ROFF_MAX == (t = roff_parse(*bufp, &pos)))
+	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
@@ -641,8 +861,8 @@ roff_cond_sub(ROFF_ARGS)
 				return(ROFF_IGN);
 
 	assert(roffs[t].proc);
-	return((*roffs[t].proc)
-			(r, t, bufp, szp, ln, ppos, pos, offs));
+	return((*roffs[t].proc)(r, t, bufp, szp, 
+				ln, ppos, pos, offs));
 }
 
 
@@ -660,28 +880,69 @@ roff_cond_text(ROFF_ARGS)
 	 * 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);
 	}
 
-	if (ep > st && '\\' != *(ep - 1)) {
-		ep = '\0';
+	if (ep == st || (ep > st && '\\' != *(ep - 1)))
 		roffnode_pop(r);
-	}
 
 	roffnode_cleanscope(r);
 	return(ROFFRULE_DENY == rr ? ROFF_IGN : ROFF_CONT);
 }
 
 
+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)
+{
+
+	return(ROFF_IGN);
+}
+
+/* ARGSUSED */
+static enum rofferr
+roff_line_error(ROFF_ARGS)
+{
+
+	(*r->msg)(MANDOCERR_REQUEST, r->data, ln, ppos, roffs[tok].name);
+	return(ROFF_IGN);
+}
+
 /* ARGSUSED */
 static enum rofferr
 roff_cond(ROFF_ARGS)
 {
-	int		 cpos;  /* position of the condition */
 	int		 sv;
+	enum roffrule	 rule;
 
 	/* Stack overflow! */
 
@@ -690,20 +951,22 @@ roff_cond(ROFF_ARGS)
 		return(ROFF_ERR);
 	}
 
-	cpos = pos;
+	/* First, evaluate the conditional. */
 
-	if (ROFF_if == tok || ROFF_ie == tok) {
-		/*
-		 * Read ahead past the conditional.  FIXME: this does
-		 * not work, as conditionals don't end on whitespace,
-		 * but are parsed according to a formal grammar.  It's
-		 * good enough for now, however.
-		 */
-		while ((*bufp)[pos] && ' ' != (*bufp)[pos])
-			pos++;
-	}
+	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);
 
 	sv = pos;
+
 	while (' ' == (*bufp)[pos])
 		pos++;
 
@@ -713,30 +976,19 @@ roff_cond(ROFF_ARGS)
 	 * really doing anything.  Warn about this.  It's probably
 	 * wrong.
 	 */
+
 	if ('\0' == (*bufp)[pos] && sv != pos) {
-		if ( ! (*r->msg)(MANDOCERR_NOARGS, r->data, ln, ppos, NULL))
-			return(ROFF_ERR);
+		(*r->msg)(MANDOCERR_NOARGS, r->data, ln, ppos, NULL);
 		return(ROFF_IGN);
 	}
 
-	if ( ! roffnode_push(r, tok, ln, ppos))
-		return(ROFF_ERR);
+	roffnode_push(r, tok, NULL, ln, ppos);
 
-	/* XXX: Implement more conditionals. */
+	r->last->rule = rule;
+
+	ROFF_DEBUG("roff: cond: %s -> %s\n", roffs[tok].name, 
+			ROFFRULE_ALLOW == rule ?  "allow" : "deny");
 
-	if (ROFF_if == tok || ROFF_ie == tok)
-		r->last->rule = 'n' == (*bufp)[cpos] ?
-		    ROFFRULE_ALLOW : ROFFRULE_DENY;
-	else 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)
-			r->last->rule = ROFFRULE_DENY;
-		else
-			r->last->rule = r->rstack[r->rstackpos];
-	}
 	if (ROFF_ie == tok) {
 		/*
 		 * An if-else will put the NEGATION of the current
@@ -748,15 +1000,31 @@ roff_cond(ROFF_ARGS)
 		else
 			r->rstack[r->rstackpos] = ROFFRULE_DENY;
 	}
-	if (r->last->parent && ROFFRULE_DENY == r->last->parent->rule)
+
+	/* 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;
+		ROFF_DEBUG("roff: cond override: %s -> deny\n",
+				roffs[tok].name);
+	}
+
+	/*
+	 * 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.
+	 */
 
 	r->last->endspan = 1;
 
 	if ('\\' == (*bufp)[pos] && '{' == (*bufp)[pos + 1]) {
 		r->last->endspan = -1;
 		pos += 2;
-	} 
+		ROFF_DEBUG("roff: cond-scope: %s, multi-line\n", 
+				roffs[tok].name);
+	} else
+		ROFF_DEBUG("roff: cond-scope: %s, one-line\n", 
+				roffs[tok].name);
 
 	/*
 	 * If there are no arguments on the line, the next-line scope is
@@ -775,8 +1043,300 @@ roff_cond(ROFF_ARGS)
 
 /* ARGSUSED */
 static enum rofferr
-roff_line(ROFF_ARGS)
+roff_ds(ROFF_ARGS)
 {
+	char		*name, *string;
 
+	/*
+	 * 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.
+	 */
+
+	name = *bufp + pos;
+	if ('\0' == *name)
+		return(ROFF_IGN);
+
+	string = name;
+	/* Read until end of name. */
+	while (*string && ' ' != *string)
+		string++;
+
+	/* Nil-terminate name. */
+	if (*string)
+		*(string++) = '\0';
+	
+	/* Read past spaces. */
+	while (*string && ' ' == *string)
+		string++;
+
+	/* Read passed initial double-quote. */
+	if (*string && '"' == *string)
+		string++;
+
+	/* The rest is the value. */
+	roff_setstr(r, name, string, 0);
 	return(ROFF_IGN);
 }
+
+
+/* ARGSUSED */
+static enum rofferr
+roff_nr(ROFF_ARGS)
+{
+	const char	*key, *val;
+	struct reg	*rg;
+
+	key = &(*bufp)[pos];
+	rg = r->regs->regs;
+
+	/* Parse register request. */
+	while ((*bufp)[pos] && ' ' != (*bufp)[pos])
+		pos++;
+
+	/*
+	 * Set our nil terminator.  Because this line is going to be
+	 * ignored anyway, we can munge it as we please.
+	 */
+	if ((*bufp)[pos])
+		(*bufp)[pos++] = '\0';
+
+	/* Skip whitespace to register token. */
+	while ((*bufp)[pos] && ' ' == (*bufp)[pos])
+		pos++;
+
+	val = &(*bufp)[pos];
+
+	/* Process register token. */
+
+	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;
+
+		ROFF_DEBUG("roff: register nS: %u\n", 
+				rg[(int)REG_nS].v.u);
+	} else
+		ROFF_DEBUG("roff: ignoring register: %s\n", key);
+
+	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, quoted, pairs;
+
+	/*
+	 * Collect pointers to macro argument strings
+	 * and null-terminate them.
+	 */
+	cp = *bufp + pos;
+	for (i = 0; i < 9; i++) {
+		/* Quoting can only start with a new word. */
+		if ('"' == *cp) {
+			quoted = 1;
+			cp++;
+		} else
+			quoted = 0;
+		arg[i] = cp;
+		for (pairs = 0; '\0' != *cp; cp++) {
+			/* Unquoted arguments end at blanks. */
+			if (0 == quoted) {
+				if (' ' == *cp)
+					break;
+				continue;
+			}
+			/* After pairs of quotes, move left. */
+			if (pairs)
+				cp[-pairs] = cp[0];
+			/* Pairs of quotes do not end words, ... */
+			if ('"' == cp[0] && '"' == cp[1]) {
+				pairs++;
+				cp++;
+				continue;
+			}
+			/* ... but solitary quotes do. */
+			if ('"' != *cp)
+				continue;
+			if (pairs)
+				cp[-pairs] = '\0';
+			*cp = ' ';
+			break;
+		}
+		/* Last argument; the remaining ones are empty strings. */
+		if ('\0' == *cp)
+			continue;
+		/* Null-terminate argument and move to the next one. */
+		*cp++ = '\0';
+		while (' ' == *cp)
+			cp++;
+	}
+
+	/*
+	 * 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;
+		}
+
+		*szp = strlen(n1) - 3 + strlen(arg[i]) + 1;
+		n2 = mandoc_malloc(*szp);
+
+		strlcpy(n2, n1, (size_t)(cp - n1 + 1));
+		strlcat(n2, arg[i], *szp);
+		strlcat(n2, cp + 3, *szp);
+
+		cp = n2 + (cp - n1);
+		free(n1);
+		n1 = n2;
+	}
+
+	/*
+	 * Replace the macro invocation
+	 * by the expanded macro.
+	 */
+	free(*bufp);
+	*bufp = n1;
+	if (0 == *szp)
+		*szp = strlen(*bufp) + 1;
+
+	return(*szp > 1 && '\n' == (*bufp)[(int)*szp - 2] ?
+	   ROFF_REPARSE : ROFF_APPEND);
+}
+
+/*
+ * 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;
+
+	/* 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;
+	}
+
+	if (NULL == string)
+		return;
+
+	/*
+	 * 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;
+
+	/* 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)
+{
+	const struct roffstr *n;
+
+	n = r->first_string;
+	while (n && (strncmp(name, n->name, len) || '\0' != n->name[(int)len]))
+		n = n->next;
+
+	return(n ? n->string : NULL);
+}
+
+
+static void
+roff_freestr(struct roff *r)
+{
+	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;
+}