+#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_am,
+ ROFF_ami,
+ ROFF_am1,
+ ROFF_de,
+ ROFF_dei,
+ ROFF_de1,
+ ROFF_ds,
+ ROFF_el,
+ ROFF_ie,
+ ROFF_if,
+ ROFF_ig,
+ ROFF_rm,
+ ROFF_tr,
+ ROFF_cblock,
+ ROFF_ccond, /* FIXME: remove this. */
+ ROFF_nr,
+ ROFF_MAX
+};
+
+enum roffrule {
+ ROFFRULE_ALLOW,
+ 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;
+};
+
+struct roffnode {
+ enum rofft tok; /* type of node */
+ struct roffnode *parent; /* up one in stack */
+ int line; /* parse line */
+ int col; /* parse col */
+ 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 */ \
+ 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 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 const char *roff_getstrn(const struct roff *,
+ const char *, size_t);
+static enum rofferr roff_line(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 *);
+static char *roff_strdup(const char *);
+
+/* 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] = {
+ { "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 },
+ { "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 },
+ { ".", roff_cblock, NULL, NULL, 0, NULL },
+ { "\\}", roff_ccond, NULL, NULL, 0, NULL },
+ { "nr", roff_nr, NULL, NULL, 0, NULL },
+};
+
+static void roff_free1(struct roff *);
+static enum rofft roff_hash_find(const char *);
+static void roff_hash_init(void);
+static void roffnode_cleanscope(struct roff *);
+static void roffnode_push(struct roff *,
+ enum rofft, int, int);
+static void roffnode_pop(struct roff *);
+static enum rofft roff_parse(const char *, int *);
+static int roff_parse_nat(const char *, unsigned int *);
+
+/* See roff_hash_find() */
+#define ROFF_HASH(p) (p[0] - ASCII_LO)
+
+static void
+roff_hash_init(void)
+{
+ struct roffmac *n;
+ int buc, i;
+
+ for (i = 0; i < (int)ROFF_MAX; 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
+roff_hash_find(const char *p)
+{
+ 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.
+ */
+
+ if (p[0] < ASCII_LO || p[0] > ASCII_HI)
+ return(ROFF_MAX);
+
+ buc = ROFF_HASH(p);
+
+ if (NULL == (n = hash[buc]))
+ return(ROFF_MAX);
+ for ( ; n; n = n->next)
+ if (0 == strcmp(n->name, p))
+ return((enum rofft)(n - roffs));
+
+ return(ROFF_MAX);
+}
+
+
+/*
+ * Pop the current node off of the stack of roff instructions currently
+ * pending.
+ */
+static void
+roffnode_pop(struct roff *r)
+{
+ struct roffnode *p;
+
+ assert(r->last);
+ p = r->last;
+
+ if (ROFF_el == p->tok)
+ 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);
+}
+
+
+/*
+ * 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, int line, int col)
+{
+ struct roffnode *p;
+
+ p = mandoc_calloc(1, sizeof(struct roffnode));
+ p->tok = tok;
+ p->parent = r->last;
+ p->line = line;
+ p->col = col;
+ p->rule = p->parent ? p->parent->rule : ROFFRULE_DENY;
+
+ r->last = p;
+}
+
+
+static void
+roff_free1(struct roff *r)
+{
+
+ while (r->last)
+ roffnode_pop(r);
+ roff_freestr(r);
+}
+
+
+void
+roff_reset(struct roff *r)
+{
+
+ roff_free1(r);
+}
+
+
+void
+roff_free(struct roff *r)
+{
+
+ roff_free1(r);
+ free(r);
+}
+
+
+struct roff *
+roff_alloc(struct regset *regs, void *data, const mandocmsg msg)
+{
+ struct roff *r;
+
+ r = mandoc_calloc(1, sizeof(struct roff));
+ r->regs = regs;
+ r->msg = msg;
+ r->data = data;
+ r->rstackpos = -1;
+
+ roff_hash_init();
+ 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.
+ */
+static int
+roff_res(struct roff *r, char **bufp, size_t *szp, int pos)
+{
+ const char *cp, *cpp, *st, *res;
+ int i, maxl;
+ size_t nsz;
+ char *n;
+
+ /* LINTED */
+ for (cp = &(*bufp)[pos]; (cpp = strstr(cp, "\\*")); cp++) {
+ cp = cpp + 2;
+ switch (*cp) {
+ case ('('):
+ cp++;
+ maxl = 2;
+ break;
+ case ('['):
+ cp++;
+ maxl = 0;
+ break;
+ default:
+ maxl = 1;
+ break;
+ }
+
+ st = cp;
+
+ for (i = 0; 0 == maxl || i < maxl; i++, cp++) {
+ if ('\0' == *cp)
+ return(1); /* Error. */
+ if (0 == maxl && ']' == *cp)
+ break;
+ }
+
+ res = roff_getstrn(r, st, (size_t)i);
+
+ if (NULL == res) {
+ cp -= maxl ? 1 : 0;
+ continue;
+ }
+
+ ROFF_DEBUG("roff: splicing reserved: [%.*s]\n", i, st);
+
+ nsz = *szp + strlen(res) + 1;
+ n = mandoc_malloc(nsz);
+
+ *n = '\0';
+
+ strlcat(n, *bufp, (size_t)(cpp - *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)
+{
+ 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_RERUN);
+
+ /*
+ * 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.
+ */
+
+ 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));
+ } else if ( ! ROFF_CTL((*bufp)[pos]))
+ return(ROFF_CONT);
+
+ /*
+ * If a scope is open, go to the child handler for that macro,
+ * as it may want to preprocess before doing anything with it.
+ */
+
+ 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));
+ }
+
+ /*
+ * 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(*bufp, &pos)))
+ return(ROFF_CONT);
+
+ ROFF_DEBUG("roff: intercept new-scope: %s, [%s]\n",
+ roffs[t].name, &(*bufp)[pos]);
+ assert(roffs[t].proc);
+ return((*roffs[t].proc)
+ (r, t, bufp, szp,
+ ln, ppos, pos, offs));
+}
+
+
+int
+roff_endparse(struct roff *r)
+{
+
+ if (NULL == r->last)
+ return(1);
+ return((*r->msg)(MANDOCERR_SCOPEEXIT, r->data, r->last->line,
+ r->last->col, NULL));
+}
+
+
+/*
+ * 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)
+{
+ int j;
+ char mac[5];
+ enum rofft t;
+
+ assert(ROFF_CTL(buf[*pos]));
+ (*pos)++;
+
+ while (buf[*pos] && (' ' == 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';
+
+ if (ROFF_MAX == (t = roff_hash_find(mac)))
+ return(t);
+
+ while (buf[*pos] && ' ' == buf[*pos])
+ (*pos)++;
+
+ return(t);
+}
+
+
+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)
+{
+
+ /*
+ * 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) {
+ if ( ! (*r->msg)(MANDOCERR_NOSCOPE, r->data, ln, ppos, NULL))
+ return(ROFF_ERR);
+ return(ROFF_IGN);
+ }
+
+ switch (r->last->tok) {
+ case (ROFF_am):
+ /* FALLTHROUGH */
+ case (ROFF_ami):
+ /* FALLTHROUGH */
+ case (ROFF_am1):
+ /* FALLTHROUGH */
+ case (ROFF_de):
+ /* FALLTHROUGH */
+ case (ROFF_dei):
+ /* FALLTHROUGH */
+ case (ROFF_de1):
+ /* FALLTHROUGH */
+ case (ROFF_ig):
+ break;
+ default:
+ if ( ! (*r->msg)(MANDOCERR_NOSCOPE, r->data, ln, ppos, NULL))
+ return(ROFF_ERR);
+ return(ROFF_IGN);
+ }
+
+ if ((*bufp)[pos])
+ if ( ! (*r->msg)(MANDOCERR_ARGSLOST, r->data, ln, pos, NULL))
+ return(ROFF_ERR);
+
+ 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
+roff_ccond(ROFF_ARGS)
+{
+
+ if (NULL == r->last) {
+ if ( ! (*r->msg)(MANDOCERR_NOSCOPE, r->data, ln, ppos, NULL))
+ return(ROFF_ERR);
+ return(ROFF_IGN);
+ }
+
+ switch (r->last->tok) {
+ case (ROFF_el):
+ /* FALLTHROUGH */
+ case (ROFF_ie):
+ /* FALLTHROUGH */
+ case (ROFF_if):
+ break;
+ default:
+ if ( ! (*r->msg)(MANDOCERR_NOSCOPE, r->data, ln, ppos, NULL))
+ return(ROFF_ERR);
+ return(ROFF_IGN);
+ }
+
+ if (r->last->endspan > -1) {
+ if ( ! (*r->msg)(MANDOCERR_NOSCOPE, r->data, ln, ppos, NULL))
+ return(ROFF_ERR);
+ return(ROFF_IGN);
+ }
+
+ if ((*bufp)[pos])
+ if ( ! (*r->msg)(MANDOCERR_ARGSLOST, r->data, ln, pos, NULL))
+ return(ROFF_ERR);
+
+ roffnode_pop(r);
+ roffnode_cleanscope(r);
+ return(ROFF_IGN);
+}
+
+
+/* ARGSUSED */
+static enum rofferr
+roff_block(ROFF_ARGS)
+{
+ int sv;
+ size_t sz;
+
+ 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++;
+ }
+
+ roffnode_push(r, tok, ln, ppos);
+
+ if ('\0' == (*bufp)[pos])
+ return(ROFF_IGN);
+
+ 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.
+ */
+
+ assert(pos > sv);
+ sz = (size_t)(pos - sv);
+
+ if (1 == sz && '.' == (*bufp)[sv])
+ return(ROFF_IGN);
+
+ 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);
+
+ return(ROFF_IGN);
+}
+
+
+/* ARGSUSED */
+static enum rofferr
+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) {
+ i = pos + 1;
+ while (' ' == (*bufp)[i] || '\t' == (*bufp)[i])
+ i++;
+
+ 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(*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.
+ */
+
+ ppos = pos;
+ t = roff_parse(*bufp, &pos);
+
+ /* If we're not a comment-end, then throw it away. */
+ if (ROFF_cblock != t)
+ 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)
+{
+
+ return(ROFF_IGN);
+}
+
+
+/* ARGSUSED */
+static enum rofferr
+roff_cond_sub(ROFF_ARGS)
+{
+ enum rofft t;
+ enum roffrule rr;
+
+ ppos = pos;
+ rr = r->last->rule;
+
+ /*
+ * Clean out scope. If we've closed ourselves, then don't
+ * continue.
+ */
+
+ roffnode_cleanscope(r);
+
+ if (ROFF_MAX == (t = roff_parse(*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 enum rofferr
+roff_cond_text(ROFF_ARGS)
+{
+ char *ep, *st;
+ enum roffrule rr;
+
+ rr = r->last->rule;
+
+ /*
+ * 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);
+ }
+
+ 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(ROFF_ARGS)
+{
+
+ return(ROFF_IGN);
+}
+
+
+/* ARGSUSED */
+static enum rofferr
+roff_cond(ROFF_ARGS)
+{
+ int sv;
+ enum roffrule rule;
+
+ /* Stack overflow! */
+
+ if (ROFF_ie == tok && r->rstackpos == RSTACK_MAX - 1) {
+ (*r->msg)(MANDOCERR_MEM, r->data, ln, ppos, NULL);
+ return(ROFF_ERR);
+ }
+
+ /* First, evaluate the conditional. */
+
+ 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++;
+
+ /*
+ * 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) {
+ if ((*r->msg)(MANDOCERR_NOARGS, r->data, ln, ppos, NULL))
+ return(ROFF_IGN);
+ return(ROFF_ERR);
+ }
+
+ roffnode_push(r, tok, ln, ppos);
+
+ r->last->rule = rule;
+
+ ROFF_DEBUG("roff: cond: %s -> %s\n", roffs[tok].name,
+ ROFFRULE_ALLOW == rule ? "allow" : "deny");
+
+ 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;
+ 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
+ * 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.
+ */
+
+ 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);
+ 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);
+}
+
+
+static char *
+roff_strdup(const char *name)
+{
+ char *namecopy, *sv;
+
+ /*
+ * This isn't a nice simple mandoc_strdup() because we must
+ * handle roff's stupid double-escape rule.
+ */
+ sv = namecopy = mandoc_malloc(strlen(name) + 1);
+ while (*name) {
+ if ('\\' == *name && '\\' == *(name + 1))
+ name++;
+ *namecopy++ = *name++;
+ }
+
+ *namecopy = '\0';
+ return(sv);
+}
+
+
+static void
+roff_setstr(struct roff *r, const char *name, const char *string)
+{
+ struct roffstr *n;
+ char *namecopy;
+
+ n = r->first_string;
+ while (n && strcmp(name, n->name))
+ n = n->next;
+
+ if (NULL == n) {
+ namecopy = mandoc_strdup(name);
+ n = mandoc_malloc(sizeof(struct roffstr));
+ n->name = namecopy;
+ n->next = r->first_string;
+ r->first_string = n;
+ } else
+ free(n->string);
+
+ /* Don't use mandoc_strdup: clean out double-escapes. */
+ n->string = string ? roff_strdup(string) : NULL;
+ ROFF_DEBUG("roff: new symbol: [%s] = [%s]\n", name, n->string);
+}
+
+
+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;
+}