Fix border condition in `tr' grokking arguments.

[mandoc.git] / roff.c

diff --git a/roff.c b/roff.c
index 3e2d2ce561d45c069bb645038251c9a311ff373f..ac75b2a8ba6f5110625479a5282c4448780e9b05 100644 (file)
--- a/roff.c
+++ b/roff.c
@@ -1,14 +1,15 @@
-/*     $Id: roff.c,v 1.67 2010/05/15 18:35:14 kristaps Exp $ */
+/*     $Id: roff.c,v 1.165 2011/07/28 14:53:22 kristaps Exp $ */

 /*
 /*

- * Copyright (c) 2010 Kristaps Dzonsons <kristaps@bsd.lv>
+ * 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.
  *
  *
  * 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
  * 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
  * 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


@@ -19,26 +20,90 @@
 #endif
 
 #include <assert.h>
 #endif
 
 #include <assert.h>

+#include <ctype.h>

 #include <stdlib.h>
 #include <string.h>
 
 #include "mandoc.h"
 #include <stdlib.h>
 #include <string.h>
 
 #include "mandoc.h"

-#include "roff.h"
+#include "libroff.h"
+#include "libmandoc.h"
+
+/* Maximum number of nested if-else conditionals. */
+#define        RSTACK_MAX      128

 
 enum   rofft {
 
 enum   rofft {

-       ROFF_de,
-       ROFF_dei,
+       ROFF_ad,

        ROFF_am,
        ROFF_ami,
        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_ig,

-       ROFF_close,
+       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,
+       ROFF_USERDEF,

        ROFF_MAX
 };
 
        ROFF_MAX
 };
 

+enum   roffrule {
+       ROFFRULE_ALLOW,
+       ROFFRULE_DENY
+};
+
+/*
+ * A single register entity.  If "set" is zero, the value of the
+ * register should be the default one, which is per-register.
+ * Registers are assumed to be unsigned ints for now.
+ */
+struct reg {
+       int               set; /* whether set or not */
+       unsigned int      u; /* unsigned integer */
+};
+
+struct roffstr {
+       char            *key; /* key of symbol */
+       size_t           keysz;
+       char            *val; /* current value */
+       size_t           valsz;
+       struct roffstr  *next; /* next in list */
+};
+

 struct roff {
 struct roff {

+       struct mparse   *parse; /* parse point */

        struct roffnode *last; /* leaf of stack */
        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 reg       regs[REG__MAX];
+       struct roffstr  *strtab; /* user-defined strings & macros */
+       struct roffstr  *chrtab; /* user-defined characters */
+       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 {
 };
 
 struct roffnode {


@@ -46,59 +111,183 @@ struct    roffnode {
        struct roffnode *parent; /* up one in stack */
        int              line; /* parse line */
        int              col; /* parse col */
        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 */

 };
 
 #define        ROFF_ARGS        struct roff *r, /* parse ctx */ \
 };
 
 #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 */ \
                         char **bufp, /* input buffer */ \
                         size_t *szp, /* size of input buffer */ \
                         int ln, /* parse line */ \

-                        int ppos /* current pos in buffer */
+                        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 */
 
 typedef        enum rofferr (*roffproc)(ROFF_ARGS);
 
 struct roffmac {
        const char      *name; /* macro name */

-       roffproc         sub; /* child of control black */
-       roffproc         new; /* root of stack (type = ROFF_MAX) */
+       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 enum rofferr     roff_ignore(ROFF_ARGS);
-static enum rofferr     roff_new_close(ROFF_ARGS);
-static enum rofferr     roff_new_ig(ROFF_ARGS);
-static enum rofferr     roff_sub_ig(ROFF_ARGS);
-
-const  struct roffmac   roffs[ROFF_MAX] = {
-       { "de", NULL, roff_ignore },
-       { "dei", NULL, roff_ignore },
-       { "am", NULL, roff_ignore },
-       { "ami", NULL, roff_ignore },
-       { "ig", roff_sub_ig, roff_new_ig },
-       { ".", NULL, roff_new_close },
+struct predef {
+       const char      *name; /* predefined input name */
+       const char      *str; /* replacement symbol */

 };
 
 };
 

-static void             roff_alloc1(struct roff *);
-static void             roff_free1(struct roff *);
-static enum rofft       roff_hash_find(const char *);
-static int              roffnode_push(struct roff *, 
-                               enum rofft, int, int);
+#define        PREDEF(__name, __str) \
+       { (__name), (__str) },
+
+static enum rofft       roffhash_find(const char *, size_t);
+static void             roffhash_init(void);
+static void             roffnode_cleanscope(struct roff *);

 static void             roffnode_pop(struct roff *);
 static void             roffnode_pop(struct roff *);

-static enum rofft       roff_parse(const char *, int *);
+static void             roffnode_push(struct roff *, enum rofft,
+                               const char *, int, int);
+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_free1(struct roff *);
+static void             roff_freestr(struct roffstr **);
+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 void             roff_openeqn(struct roff *, const char *, 
+                               int, int, const char *);
+static enum rofft       roff_parse(struct roff *, const char *, int *);
+static enum rofferr     roff_parsetext(char *);
+static void             roff_res(struct roff *, 
+                               char **, size_t *, int, int);
+static enum rofferr     roff_rm(ROFF_ARGS);
+static void             roff_setstr(struct roff *,
+                               const char *, const char *, int);
+static void             roff_setstrn(struct roffstr **, const char *, 
+                               size_t, const char *, size_t, int);
+static enum rofferr     roff_so(ROFF_ARGS);
+static enum rofferr     roff_tr(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 roffhash_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_tr, 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 },
+};

 
 

+/* Array of injected predefined strings. */
+#define        PREDEFS_MAX      38
+static const struct predef predefs[PREDEFS_MAX] = {
+#include "predefs.in"
+};
+
+/* See roffhash_find() */
+#define        ROFF_HASH(p)    (p[0] - ASCII_LO)
+
+static void
+roffhash_init(void)
+{
+       struct roffmac   *n;
+       int               buc, i;
+
+       for (i = 0; i < (int)ROFF_USERDEF; i++) {
+               assert(roffs[i].name[0] >= ASCII_LO);
+               assert(roffs[i].name[0] <= ASCII_HI);
+
+               buc = ROFF_HASH(roffs[i].name);
+
+               if (NULL != (n = hash[buc])) {
+                       for ( ; n->next; n = n->next)
+                               /* Do nothing. */ ;
+                       n->next = &roffs[i];
+               } else
+                       hash[buc] = &roffs[i];
+       }
+}

 
 /*
  * 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
 
 /*
  * 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)
+roffhash_find(const char *p, size_t s)

 {
 {

-       int              i;
+       int              buc;
+       struct roffmac  *n;
+
+       /*
+        * 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.
+        */

 
 

-       /* FIXME: make this be fast and efficient. */
+       if (p[0] < ASCII_LO || p[0] > ASCII_HI)
+               return(ROFF_MAX);

 
 

-       for (i = 0; i < (int)ROFF_MAX; i++)
-               if (0 == strcmp(roffs[i].name, p))
-                       return((enum rofft)i);
+       buc = ROFF_HASH(p);
+
+       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(ROFF_MAX);
 }
 
        return(ROFF_MAX);
 }


@@ -113,9 +302,12 @@ roffnode_pop(struct roff *r)
 {
        struct roffnode *p;
 
 {
        struct roffnode *p;
 

-       if (NULL == (p = r->last))
-               return;
-       r->last = p->parent;
+       assert(r->last);
+       p = r->last; 
+
+       r->last = r->last->parent;
+       free(p->name);
+       free(p->end);

        free(p);
 }
 
        free(p);
 }
 


@@ -124,49 +316,64 @@ roffnode_pop(struct roff *r)
  * Push a roff node onto the instruction stack.  This must later be
  * removed with roffnode_pop().
  */
  * 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;
 
 {
        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;
        p->tok = tok;

+       if (name)
+               p->name = mandoc_strdup(name);

        p->parent = r->last;
        p->line = line;
        p->col = col;
        p->parent = r->last;
        p->line = line;
        p->col = col;

+       p->rule = p->parent ? p->parent->rule : ROFFRULE_DENY;

 
        r->last = p;
 
        r->last = p;

-       return(1);

 }
 
 
 static void
 roff_free1(struct roff *r)
 {
 }
 
 
 static void
 roff_free1(struct roff *r)
 {

+       struct tbl_node *t;
+       struct eqn_node *e;

 
 

-       while (r->last)
-               roffnode_pop(r);
-}
+       while (NULL != (t = r->first_tbl)) {
+               r->first_tbl = t->next;
+               tbl_free(t);
+       }

 
 

+       r->first_tbl = r->last_tbl = r->tbl = NULL;

 
 

-static void
-roff_alloc1(struct roff *r)
-{
+       while (NULL != (e = r->first_eqn)) {
+               r->first_eqn = e->next;
+               eqn_free(e);
+       }

 
 

-       memset(r, 0, sizeof(struct roff));
+       r->first_eqn = r->last_eqn = r->eqn = NULL;
+
+       while (r->last)
+               roffnode_pop(r);
+
+       roff_freestr(&r->strtab);
+       roff_freestr(&r->chrtab);

 }
 
 
 void
 roff_reset(struct roff *r)
 {
 }
 
 
 void
 roff_reset(struct roff *r)
 {

+       int              i;

 
        roff_free1(r);
 
        roff_free1(r);

-       roff_alloc1(r);
+
+       memset(&r->regs, 0, sizeof(struct reg) * REG__MAX);
+
+       for (i = 0; i < PREDEFS_MAX; i++) 
+               roff_setstr(r, predefs[i].name, predefs[i].str, 0);

 }
 
 
 }
 
 


@@ -180,82 +387,314 @@ roff_free(struct roff *r)
 
 
 struct roff *
 
 
 struct roff *

-roff_alloc(const mandocmsg msg, void *data)
+roff_alloc(struct mparse *parse)

 {
        struct roff     *r;
 {
        struct roff     *r;

+       int              i;

 
 

-       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->parse = parse;
+       r->rstackpos = -1;
+       
+       roffhash_init();
+
+       for (i = 0; i < PREDEFS_MAX; i++) 
+               roff_setstr(r, predefs[i].name, predefs[i].str, 0);

 
 

-       r->msg = msg;
-       r->data = data;

        return(r);
 }
 
        return(r);
 }
 

+/*
+ * 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. 
+ * This also checks the syntax of regular escapes.
+ */
+static void
+roff_res(struct roff *r, char **bufp, size_t *szp, int ln, int pos)
+{
+       enum mandoc_esc  esc;
+       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;
+
+again:
+       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;
+
+               if ('*' != *cp) {
+                       res = cp;
+                       esc = mandoc_escape(&cp, NULL, NULL);
+                       if (ESCAPE_ERROR != esc)
+                               continue;
+                       cp = res;
+                       mandoc_msg
+                               (MANDOCERR_BADESCAPE, r->parse, 
+                                ln, (int)(stesc - *bufp), NULL);
+                       return;
+               }
+
+               cp++;
+
+               /*
+                * The third character decides the length
+                * of the name of the string.
+                * Save a pointer to the name.
+                */
+
+               switch (*cp) {
+               case ('\0'):
+                       return;
+               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) {
+                               mandoc_msg
+                                       (MANDOCERR_BADESCAPE, 
+                                        r->parse, ln, 
+                                        (int)(stesc - *bufp), NULL);
+                               return;
+                       }
+                       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) {
+                       mandoc_msg
+                               (MANDOCERR_BADESCAPE, r->parse, 
+                                ln, (int)(stesc - *bufp), NULL);
+                       res = "";
+               }
+
+               /* Replace the escape sequence by the string. */
+
+               pos = stesc - *bufp;
+
+               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;
+               goto again;
+       }
+}
+
+/*
+ * Process text streams: convert all breakable hyphens into ASCII_HYPH.
+ */
+static enum rofferr
+roff_parsetext(char *p)
+{
+       char             l, r;
+       size_t           sz;
+       const char      *start;
+       enum mandoc_esc  esc;
+
+       start = p;
+
+       while ('\0' != *p) {
+               sz = strcspn(p, "-\\");
+               p += sz;
+
+               if ('\0' == *p)
+                       break;
+
+               if ('\\' == *p) {
+                       /* Skip over escapes. */
+                       p++;
+                       esc = mandoc_escape
+                               ((const char **)&p, NULL, NULL);
+                       if (ESCAPE_ERROR == esc)
+                               break;
+                       continue;
+               } else if (p == start) {
+                       p++;
+                       continue;
+               }
+
+               l = *(p - 1);
+               r = *(p + 1);
+               if ('\\' != l &&
+                               '\t' != r && '\t' != l &&
+                               ' ' != r && ' ' != l &&
+                               '-' != r && '-' != l &&
+                               ! isdigit((unsigned char)l) &&
+                               ! isdigit((unsigned char)r))
+                       *p = ASCII_HYPH;
+               p++;
+       }
+
+       return(ROFF_CONT);
+}

 
 enum rofferr
 
 enum rofferr

-roff_parseln(struct roff *r, int ln, char **bufp, size_t *szp)
+roff_parseln(struct roff *r, int ln, char **bufp, 
+               size_t *szp, int pos, int *offs)

 {
        enum rofft       t;
 {
        enum rofft       t;

-       int              ppos;
+       enum rofferr     e;
+       int              ppos, ctl;

 
 

-       if (NULL != r->last) {
-               /*
-                * If there's a node on the stack, then jump directly
-                * into its processing function.
-                */
+       /*
+        * Run the reserved-word filter only if we have some reserved
+        * words to fill in.
+        */
+
+       roff_res(r, bufp, szp, ln, pos);
+
+       ppos = pos;
+       ctl = mandoc_getcontrol(*bufp, &pos);
+
+       /*
+        * 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 && ! ctl) {
+               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, pos, offs));
+               if (r->tbl)
+                       return(tbl_read(r->tbl, ln, *bufp, pos));
+               return(roff_parsetext(*bufp + pos));
+       } else if ( ! ctl) {
+               if (r->eqn)
+                       return(eqn_read(&r->eqn, ln, *bufp, pos, offs));
+               if (r->tbl)
+                       return(tbl_read(r->tbl, ln, *bufp, pos));
+               return(roff_parsetext(*bufp + pos));
+       } else if (r->eqn)
+               return(eqn_read(&r->eqn, ln, *bufp, ppos, offs));
+
+       /*
+        * 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);
                t = r->last->tok;
                assert(roffs[t].sub);

-               return((*roffs[t].sub)(r, bufp, szp, ln, 0));
-       } else if ('.' != (*bufp)[0] && NULL == r->last)
-               /* Return when in free text without a context. */
-               return(ROFF_CONT);
+               return((*roffs[t].sub)
+                               (r, t, bufp, szp, 
+                                ln, ppos, pos, offs));
+       }

 
 

-       /* There's nothing on the stack: make us anew. */
+       /*
+        * 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.
+        */

 
 

-       if (ROFF_MAX == (t = roff_parse(*bufp, &ppos)))
+       if (ROFF_MAX == (t = roff_parse(r, *bufp, &pos)))

                return(ROFF_CONT);
 
                return(ROFF_CONT);
 

-       assert(roffs[t].new);
-       return((*roffs[t].new)(r, bufp, szp, ln, ppos));
+       assert(roffs[t].proc);
+       return((*roffs[t].proc)
+                       (r, t, bufp, szp, 
+                        ln, ppos, pos, offs));

 }
 
 
 }
 
 

+void
+roff_endparse(struct roff *r)
+{
+
+       if (r->last)
+               mandoc_msg(MANDOCERR_SCOPEEXIT, r->parse,
+                               r->last->line, r->last->col, NULL);
+
+       if (r->eqn) {
+               mandoc_msg(MANDOCERR_SCOPEEXIT, r->parse, 
+                               r->eqn->eqn.ln, r->eqn->eqn.pos, NULL);
+               eqn_end(&r->eqn);
+       }
+
+       if (r->tbl) {
+               mandoc_msg(MANDOCERR_SCOPEEXIT, r->parse, 
+                               r->tbl->line, r->tbl->pos, NULL);
+               tbl_end(&r->tbl);
+       }
+}
+

 /*
  * 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
 /*
  * 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(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;
 
        enum rofft       t;
 

-       assert('.' == buf[0]);
-       *pos = 1;
-
-       while (buf[*pos] && (' ' == buf[*pos] || '\t' == buf[*pos]))
-               (*pos)++;
-
-       if ('\0' == buf[*pos])
+       if ('\0' == buf[*pos] || '"' == buf[*pos] || 
+                       '\t' == buf[*pos] || ' ' == buf[*pos])

                return(ROFF_MAX);
 
                return(ROFF_MAX);
 

-       for (j = 0; j < 4; j++, (*pos)++)
-               if ('\0' == (mac[j] = buf[*pos]))
-                       break;
-               else if (' ' == buf[*pos])
-                       break;
+       /*
+        * We stop the macro parse at an escape, tab, space, or nil.
+        * However, `\}' is also a valid macro, so make sure we don't
+        * clobber it by seeing the `\' as the end of token.
+        */

 
 

-       if (j == 4 || j < 1)
-               return(ROFF_MAX);
+       mac = buf + *pos;
+       maclen = strcspn(mac + 1, " \\\t\0") + 1;

 
 

-       mac[j] = '\0';
+       t = (r->current_string = roff_getstrn(r, mac, maclen))
+           ? ROFF_USERDEF : roffhash_find(mac, maclen);

 
 

-       if (ROFF_MAX == (t = roff_hash_find(mac)))
-               return(t);
+       *pos += (int)maclen;

 
        while (buf[*pos] && ' ' == buf[*pos])
                (*pos)++;
 
        while (buf[*pos] && ' ' == buf[*pos])
                (*pos)++;


@@ -263,66 +702,1030 @@ roff_parse(const char *buf, int *pos)
        return(t);
 }
 
        return(t);
 }
 

+/* 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) {
+               mandoc_msg(MANDOCERR_NOSCOPE, r->parse, ln, ppos, NULL);
+               return(ROFF_IGN);
+       }
+
+       switch (r->last->tok) {
+       case (ROFF_am):
+               /* FALLTHROUGH */
+       case (ROFF_ami):
+               /* FALLTHROUGH */
+       case (ROFF_am1):
+               /* FALLTHROUGH */
+       case (ROFF_de):
+               /* ROFF_de1 is remapped to ROFF_de in roff_block(). */
+               /* FALLTHROUGH */
+       case (ROFF_dei):
+               /* FALLTHROUGH */
+       case (ROFF_ig):
+               break;
+       default:
+               mandoc_msg(MANDOCERR_NOSCOPE, r->parse, ln, ppos, NULL);
+               return(ROFF_IGN);
+       }
+
+       if ((*bufp)[pos])
+               mandoc_msg(MANDOCERR_ARGSLOST, r->parse, ln, pos, NULL);
+
+       roffnode_pop(r);
+       roffnode_cleanscope(r);
+       return(ROFF_IGN);
+
+}
+
+
+static void
+roffnode_cleanscope(struct roff *r)
+{
+
+       while (r->last) {
+               if (--r->last->endspan < 0)
+                       break;
+               roffnode_pop(r);
+       }
+}
+

 
 /* ARGSUSED */
 static enum rofferr
 
 /* ARGSUSED */
 static enum rofferr

-roff_ignore(ROFF_ARGS)
+roff_ccond(ROFF_ARGS)

 {
 
 {
 

+       if (NULL == r->last) {
+               mandoc_msg(MANDOCERR_NOSCOPE, r->parse, ln, ppos, NULL);
+               return(ROFF_IGN);
+       }
+
+       switch (r->last->tok) {
+       case (ROFF_el):
+               /* FALLTHROUGH */
+       case (ROFF_ie):
+               /* FALLTHROUGH */
+       case (ROFF_if):
+               break;
+       default:
+               mandoc_msg(MANDOCERR_NOSCOPE, r->parse, ln, ppos, NULL);
+               return(ROFF_IGN);
+       }
+
+       if (r->last->endspan > -1) {
+               mandoc_msg(MANDOCERR_NOSCOPE, r->parse, ln, ppos, NULL);
+               return(ROFF_IGN);
+       }
+
+       if ((*bufp)[pos])
+               mandoc_msg(MANDOCERR_ARGSLOST, r->parse, ln, pos, NULL);
+
+       roffnode_pop(r);
+       roffnode_cleanscope(r);

        return(ROFF_IGN);
 }
 
 
 /* ARGSUSED */
 static enum rofferr
        return(ROFF_IGN);
 }
 
 
 /* ARGSUSED */
 static enum rofferr

-roff_sub_ig(ROFF_ARGS)
+roff_block(ROFF_ARGS)

 {
 {

-       enum rofft       t;
-       int              pos;
+       int             sv;
+       size_t          sz;
+       char            *name;
+
+       name = NULL;
+
+       if (ROFF_ig != tok) {
+               if ('\0' == (*bufp)[pos]) {
+                       mandoc_msg(MANDOCERR_NOARGS, r->parse, 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
+                       mandoc_msg(MANDOCERR_REQUEST, r->parse, ln, ppos,
+                           roffs[tok].name);

 
 

-       /* Ignore free-text lines. */
+               while ((*bufp)[pos] && ! isspace((unsigned char)(*bufp)[pos]))
+                       pos++;

 
 

-       if ('.' != (*bufp)[ppos])
+               while (isspace((unsigned char)(*bufp)[pos]))
+                       (*bufp)[pos++] = '\0';
+       }
+
+       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);
 
                return(ROFF_IGN);
 

-       /* Ignore macros unless it's a closing macro. */
+       /* If present, process the custom end-of-line marker. */
+
+       sv = pos;
+       while ((*bufp)[pos] && ! isspace((unsigned char)(*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.
+        */

 
 

-       t = roff_parse(*bufp, &pos);
-       if (ROFF_close != t)
+       assert(pos > sv);
+       sz = (size_t)(pos - sv);
+
+       if (1 == sz && '.' == (*bufp)[sv])

                return(ROFF_IGN);
 
                return(ROFF_IGN);
 

-       roffnode_pop(r);
+       r->last->end = mandoc_malloc(sz + 1);
+
+       memcpy(r->last->end, *bufp + sv, sz);
+       r->last->end[(int)sz] = '\0';
+
+       if ((*bufp)[pos])
+               mandoc_msg(MANDOCERR_ARGSLOST, r->parse, ln, pos, NULL);
+

        return(ROFF_IGN);
 }
 
 
 /* ARGSUSED */
 static enum rofferr
        return(ROFF_IGN);
 }
 
 
 /* ARGSUSED */
 static enum rofferr

-roff_new_close(ROFF_ARGS)
+roff_block_sub(ROFF_ARGS)

 {
 {

+       enum rofft      t;
+       int             i, j;
+
+       /*
+        * 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.
+        */
+
+       if (r->last->end) {
+               for (i = pos, 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);
+
+                       while (' ' == (*bufp)[i] || '\t' == (*bufp)[i])
+                               i++;
+
+                       pos = i;
+                       if (ROFF_MAX != roff_parse(r, *bufp, &pos))
+                               return(ROFF_RERUN);
+                       return(ROFF_IGN);
+               }
+       }
+
+       /*
+        * If we have no custom end-query or lookup failed, then try
+        * pulling it out of the hashtable.
+        */
+
+       t = roff_parse(r, *bufp, &pos);
+
+       /*
+        * 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 enum rofferr
+roff_block_text(ROFF_ARGS)
+{
+
+       if (ROFF_de == tok)
+               roff_setstr(r, r->last->name, *bufp + pos, 1);

 
 

-       if ( ! (*r->msg)(MANDOCERR_NOSCOPE, r->data, ln, ppos, NULL))
-               return(ROFF_ERR);

        return(ROFF_IGN);
 }
 
 
 /* ARGSUSED */
 static enum rofferr
        return(ROFF_IGN);
 }
 
 
 /* ARGSUSED */
 static enum rofferr

-roff_new_ig(ROFF_ARGS)
+roff_cond_sub(ROFF_ARGS)

 {
 {

+       enum rofft       t;
+       enum roffrule    rr;
+       char            *ep;
+
+       rr = r->last->rule;
+       roffnode_cleanscope(r);
+
+       /*
+        * If the macro is unknown, first check if it contains a closing
+        * delimiter `\}'.  If it does, close out our scope and return
+        * the currently-scoped rule (ignore or continue).  Else, drop
+        * into the currently-scoped rule.
+        */
+
+       if (ROFF_MAX == (t = roff_parse(r, *bufp, &pos))) {
+               ep = &(*bufp)[pos];
+               for ( ; NULL != (ep = strchr(ep, '\\')); ep++) {
+                       ep++;
+                       if ('}' != *ep)
+                               continue;
+
+                       /*
+                        * Make the \} go away.
+                        * This is a little haphazard, as it's not quite
+                        * clear how nroff does this.
+                        * If we're at the end of line, then just chop
+                        * off the \} and resize the buffer.
+                        * If we aren't, then conver it to spaces.
+                        */
+
+                       if ('\0' == *(ep + 1)) {
+                               *--ep = '\0';
+                               *szp -= 2;
+                       } else
+                               *(ep - 1) = *ep = ' ';
+
+                       roff_ccond(r, ROFF_ccond, bufp, szp, 
+                                       ln, pos, pos + 2, offs);
+                       break;
+               }
+               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));
+}

 
 

-       return(roffnode_push(r, ROFF_ig, ln, ppos) ? 
-                       ROFF_IGN : ROFF_ERR);
+/* ARGSUSED */
+static enum rofferr
+roff_cond_text(ROFF_ARGS)
+{
+       char            *ep;
+       enum roffrule    rr;
+
+       rr = r->last->rule;
+       roffnode_cleanscope(r);
+
+       ep = &(*bufp)[pos];
+       for ( ; NULL != (ep = strchr(ep, '\\')); ep++) {
+               ep++;
+               if ('}' != *ep)
+                       continue;
+               *ep = '&';
+               roff_ccond(r, ROFF_ccond, bufp, szp, 
+                               ln, pos, pos + 2, offs);
+       }
+       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)
+{
+
+       if (ROFF_it == tok)
+               mandoc_msg(MANDOCERR_REQUEST, r->parse, ln, ppos, "it");
+
+       return(ROFF_IGN);
+}
+
+/* ARGSUSED */
+static enum rofferr
+roff_cond(ROFF_ARGS)
+{
+       int              sv;
+       enum roffrule    rule;
+
+       /* 
+        * An `.el' has no conditional body: it will consume the value
+        * of the current rstack entry set in prior `ie' calls or
+        * defaults to DENY.  
+        *
+        * If we're not an `el', however, then evaluate the conditional.
+        */
+
+       rule = ROFF_el == tok ?
+               (r->rstackpos < 0 ? 
+                ROFFRULE_DENY : r->rstack[r->rstackpos--]) :
+               roff_evalcond(*bufp, &pos);
+
+       sv = pos;
+       while (' ' == (*bufp)[pos])
+               pos++;
+
+       /*
+        * 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 ('\0' == (*bufp)[pos] && sv != pos) {
+               mandoc_msg(MANDOCERR_NOARGS, r->parse, ln, ppos, NULL);
+               return(ROFF_IGN);
+       }
+
+       roffnode_push(r, tok, NULL, ln, ppos);
+
+       r->last->rule = rule;
+
+       /*
+        * An if-else will put the NEGATION of the current evaluated
+        * conditional into the stack of rules.
+        */
+
+       if (ROFF_ie == tok) {
+               if (r->rstackpos == RSTACK_MAX - 1) {
+                       mandoc_msg(MANDOCERR_MEM, 
+                               r->parse, ln, ppos, NULL);
+                       return(ROFF_ERR);
+               }
+               r->rstack[++r->rstackpos] = 
+                       ROFFRULE_DENY == r->last->rule ?
+                       ROFFRULE_ALLOW : 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;
+
+       /*
+        * 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;
+       } 
+
+       /*
+        * If there are no arguments on the line, the next-line scope is
+        * assumed.
+        */
+
+       if ('\0' == (*bufp)[pos])
+               return(ROFF_IGN);
+
+       /* Otherwise re-run the roff parser after recalculating. */
+
+       *offs = pos;
+       return(ROFF_RERUN);
+}
+
+
+/* ARGSUSED */
+static enum rofferr
+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.
+        */
+
+       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);
+}

 
 int
 
 int

-roff_endparse(struct roff *r)
+roff_regisset(const struct roff *r, enum regs reg)
+{
+
+       return(r->regs[(int)reg].set);
+}
+
+unsigned int
+roff_regget(const struct roff *r, enum regs reg)
+{
+
+       return(r->regs[(int)reg].u);
+}
+
+void
+roff_regunset(struct roff *r, enum regs reg)
+{
+
+       r->regs[(int)reg].set = 0;
+}
+
+/* ARGSUSED */
+static enum rofferr
+roff_nr(ROFF_ARGS)
+{
+       const char      *key;
+       char            *val;
+       int              iv;
+
+       val = *bufp + pos;
+       key = roff_getname(r, &val, ln, pos);
+
+       if (0 == strcmp(key, "nS")) {
+               r->regs[(int)REG_nS].set = 1;
+               if ((iv = mandoc_strntoi(val, strlen(val), 10)) >= 0)
+                       r->regs[(int)REG_nS].u = (unsigned)iv;
+               else
+                       r->regs[(int)REG_nS].u = 0u;
+       }
+
+       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, (int)(cp - *bufp));
+               if ('\0' != *name)
+                       roff_setstr(r, name, NULL, 0);
+       }
+       return(ROFF_IGN);
+}
+
+/* ARGSUSED */
+static enum rofferr
+roff_TE(ROFF_ARGS)
+{
+
+       if (NULL == r->tbl)
+               mandoc_msg(MANDOCERR_NOSCOPE, r->parse, ln, ppos, NULL);
+       else
+               tbl_end(&r->tbl);
+
+       return(ROFF_IGN);
+}
+
+/* ARGSUSED */
+static enum rofferr
+roff_T_(ROFF_ARGS)
+{
+
+       if (NULL == r->tbl)
+               mandoc_msg(MANDOCERR_NOSCOPE, r->parse, ln, ppos, NULL);
+       else
+               tbl_restart(ppos, ln, r->tbl);
+
+       return(ROFF_IGN);
+}
+
+#if 0
+static int
+roff_closeeqn(struct roff *r)
+{
+
+       return(r->eqn && ROFF_EQN == eqn_end(&r->eqn) ? 1 : 0);
+}
+#endif
+
+static void
+roff_openeqn(struct roff *r, const char *name, int line, 
+               int offs, const char *buf)
+{
+       struct eqn_node *e;
+       int              poff;
+
+       assert(NULL == r->eqn);
+       e = eqn_alloc(name, offs, line, r->parse);
+
+       if (r->last_eqn)
+               r->last_eqn->next = e;
+       else
+               r->first_eqn = r->last_eqn = e;
+
+       r->eqn = r->last_eqn = e;
+
+       if (buf) {
+               poff = 0;
+               eqn_read(&r->eqn, line, buf, offs, &poff);
+       }
+}
+
+/* ARGSUSED */
+static enum rofferr
+roff_EQ(ROFF_ARGS)
+{
+
+       roff_openeqn(r, *bufp + pos, ln, ppos, NULL);
+       return(ROFF_IGN);
+}
+
+/* ARGSUSED */
+static enum rofferr
+roff_EN(ROFF_ARGS)
+{
+
+       mandoc_msg(MANDOCERR_NOSCOPE, r->parse, ln, ppos, NULL);
+       return(ROFF_IGN);
+}
+
+/* ARGSUSED */
+static enum rofferr
+roff_TS(ROFF_ARGS)
+{
+       struct tbl_node *t;
+
+       if (r->tbl) {
+               mandoc_msg(MANDOCERR_SCOPEBROKEN, r->parse, ln, ppos, NULL);
+               tbl_end(&r->tbl);
+       }
+
+       t = tbl_alloc(ppos, ln, r->parse);
+
+       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_tr(ROFF_ARGS)
+{
+       const char      *p, *first, *second;
+       size_t           fsz, ssz;
+       enum mandoc_esc  esc;
+
+       p = *bufp + pos;
+
+       if ('\0' == *p) {
+               mandoc_msg(MANDOCERR_ARGCOUNT, r->parse, ln, ppos, NULL);
+               return(ROFF_IGN);
+       }
+
+       while ('\0' != *p) {
+               fsz = ssz = 1;
+
+               first = p++;
+               if ('\\' == *first) {
+                       esc = mandoc_escape(&p, NULL, NULL);
+                       if (ESCAPE_ERROR == esc) {
+                               mandoc_msg
+                                       (MANDOCERR_BADESCAPE, r->parse, 
+                                        ln, (int)(p - *bufp), NULL);
+                               return(ROFF_IGN);
+                       }
+                       fsz = (size_t)(p - first);
+               }
+
+               second = p++;
+               if ('\\' == *second) {
+                       esc = mandoc_escape(&p, NULL, NULL);
+                       if (ESCAPE_ERROR == esc) {
+                               mandoc_msg
+                                       (MANDOCERR_BADESCAPE, r->parse, 
+                                        ln, (int)(p - *bufp), NULL);
+                               return(ROFF_IGN);
+                       }
+                       ssz = (size_t)(p - second);
+               } else if ('\0' == *second) {
+                       mandoc_msg(MANDOCERR_ARGCOUNT, r->parse, 
+                                       ln, (int)(p - *bufp), NULL);
+                       second = " ";
+                       p--;
+               }
+
+               roff_setstrn(&r->chrtab, first, fsz, second, ssz, 0);
+       }
+
+       return(ROFF_IGN);
+}
+
+/* ARGSUSED */
+static enum rofferr
+roff_so(ROFF_ARGS)
+{
+       char *name;
+
+       mandoc_msg(MANDOCERR_SO, r->parse, 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, "/..")) {
+               mandoc_msg(MANDOCERR_SOPATH, r->parse, 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;
+
+       /*
+        * 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(r->parse, &cp, ln, &pos);
+
+       /*
+        * 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);
+}
+
+static char *
+roff_getname(struct roff *r, char **cpp, int ln, int pos)
+{
+       char     *name, *cp;
+
+       name = *cpp;
+       if ('\0' == *name)
+               return(name);
+
+       /* Read until end of name. */
+       for (cp = name; '\0' != *cp && ' ' != *cp; cp++) {
+               if ('\\' != *cp)
+                       continue;
+               cp++;
+               if ('\\' == *cp)
+                       continue;
+               mandoc_msg(MANDOCERR_NAMESC, r->parse, ln, pos, NULL);
+               *cp = '\0';
+               name = cp;
+       }
+
+       /* Nil-terminate name. */
+       if ('\0' != *cp)
+               *(cp++) = '\0';
+
+       /* Read past spaces. */
+       while (' ' == *cp)
+               cp++;
+
+       *cpp = cp;
+       return(name);
+}
+
+/*
+ * 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)

 {
 
 {
 

-       if (NULL == r->last)
-               return(1);
-       return((*r->msg)(MANDOCERR_SCOPEEXIT, r->data, 
-                               r->last->line, r->last->col, NULL));
+       roff_setstrn(&r->strtab, name, strlen(name), string,
+                       string ? strlen(string) : 0, multiline);
+}
+
+static void
+roff_setstrn(struct roffstr **r, const char *name, size_t namesz,
+               const char *string, size_t stringsz, int multiline)
+{
+       struct roffstr  *n;
+       char            *c;
+       int              i;
+       size_t           oldch, newch;
+
+       /* Search for an existing string with the same name. */
+       n = *r;
+
+       while (n && strcmp(name, n->key))
+               n = n->next;
+
+       if (NULL == n) {
+               /* Create a new string table entry. */
+               n = mandoc_malloc(sizeof(struct roffstr));
+               n->key = mandoc_strndup(name, namesz);
+               n->keysz = namesz;
+               n->val = NULL;
+               n->valsz = 0;
+               n->next = *r;
+               *r = n;
+       } else if (0 == multiline) {
+               /* In multiline mode, append; else replace. */
+               free(n->val);
+               n->val = NULL;
+               n->valsz = 0;
+       }
+
+       if (NULL == string)
+               return;
+
+       /*
+        * One additional byte for the '\n' in multiline mode,
+        * and one for the terminating '\0'.
+        */
+       newch = stringsz + (multiline ? 2u : 1u);
+
+       if (NULL == n->val) {
+               n->val = mandoc_malloc(newch);
+               *n->val = '\0';
+               oldch = 0;
+       } else {
+               oldch = n->valsz;
+               n->val = mandoc_realloc(n->val, oldch + newch);
+       }
+
+       /* Skip existing content in the destination buffer. */
+       c = n->val + (int)oldch;
+
+       /* Append new content to the destination buffer. */
+       i = 0;
+       while (i < (int)stringsz) {
+               /*
+                * Rudimentary roff copy mode:
+                * Handle escaped backslashes.
+                */
+               if ('\\' == string[i] && '\\' == string[i + 1])
+                       i++;
+               *c++ = string[i++];
+       }
+
+       /* Append terminating bytes. */
+       if (multiline)
+               *c++ = '\n';
+
+       *c = '\0';
+       n->valsz = (int)(c - n->val);
+}
+
+static const char *
+roff_getstrn(const struct roff *r, const char *name, size_t len)
+{
+       const struct roffstr *n;
+
+       for (n = r->strtab; n; n = n->next)
+               if (0 == strncmp(name, n->key, len) && 
+                               '\0' == n->key[(int)len])
+                       return(n->val);
+
+       return(NULL);
+}
+
+static void
+roff_freestr(struct roffstr **r)
+{
+       struct roffstr   *n, *nn;
+
+       for (n = *r; n; n = nn) {
+               free(n->key);
+               free(n->val);
+               nn = n->next;
+               free(n);
+       }
+
+       *r = NULL;
+}
+
+const struct tbl_span *
+roff_span(const struct roff *r)
+{
+       
+       return(r->tbl ? tbl_span(r->tbl) : NULL);
+}
+
+const struct eqn *
+roff_eqn(const struct roff *r)
+{
+       
+       return(r->last_eqn ? &r->last_eqn->eqn : NULL);
+}
+
+char
+roff_eqndelim(const struct roff *r)
+{
+
+       return('\0');
+}
+
+/*
+ * Duplicate an input string, making the appropriate character
+ * conversations (as stipulated by `tr') along the way.
+ * Returns a heap-allocated string with all the replacements made.
+ */
+char *
+roff_strdup(const struct roff *r, const char *p)
+{
+       const struct roffstr *cp;
+       char            *res;
+       const char      *pp;
+       size_t           ssz, sz;
+       enum mandoc_esc  esc;
+
+       if (NULL == r->chrtab)
+               return(mandoc_strdup(p));
+       else if ('\0' == *p)
+               return(mandoc_strdup(""));
+
+       /*
+        * Step through each character looking for term matches
+        * (remember that a `tr' can be invoked with an escape, which is
+        * a glyph but the escape is multi-character).
+        * We only do this if the character hash has been initialised
+        * and the string is >0 length.
+        */
+
+       res = NULL;
+       ssz = 0;
+
+       while ('\0' != *p) {
+               /* Search for term matches. */
+               for (cp = r->chrtab; cp; cp = cp->next)
+                       if (0 == strncmp(p, cp->key, cp->keysz))
+                               break;
+
+               if (NULL != cp) {
+                       /*
+                        * A match has been found.
+                        * Append the match to the array and move
+                        * forward by its keysize.
+                        */
+                       res = mandoc_realloc(res, ssz + cp->valsz + 1);
+                       memcpy(res + ssz, cp->val, cp->valsz);
+                       ssz += cp->valsz;
+                       p += (int)cp->keysz;
+                       continue;
+               }
+
+               if ('\\' == *p) {
+                       /*
+                        * Handle escapes carefully: we need to copy
+                        * over just the escape itself, or else we might
+                        * do replacements within the escape itself.
+                        * Make sure to pass along the bogus string.
+                        */
+                       pp = p++;
+                       esc = mandoc_escape(&p, NULL, NULL);
+                       if (ESCAPE_ERROR == esc) {
+                               sz = strlen(pp);
+                               res = mandoc_realloc(res, ssz + sz + 1);
+                               memcpy(res + ssz, pp, sz);
+                               break;
+                       }
+                       /* 
+                        * We bail out on bad escapes. 
+                        * No need to warn: we already did so when
+                        * roff_res() was called.
+                        */
+                       sz = (int)(p - pp);
+                       res = mandoc_realloc(res, ssz + sz + 1);
+                       memcpy(res + ssz, pp, sz);
+                       ssz += sz;
+                       continue;
+               }
+
+               /* Just append the charater. */
+               res = mandoc_realloc(res, ssz + 2);
+               res[ssz++] = *p++;
+       }
+
+       res[(int)ssz] = '\0';
+       return(res);

 }
 }