Unify mdoc_deroff() and man_deroff() into a common function deroff().

No functional change except that for mdoc(7), it now skips leading
escape sequences just like it already did for man(7).
Escape sequences rarely occur in mdoc(7) code and if they do,
skipping them is an improvement in this context.
Minus 30 lines of code.

1 files changed, 46 insertions, 0 deletions

diff --git a/roff.c b/roff.c
index b3f5752a..ca0f85a4 100644
--- a/roff.c
+++ b/roff.c
@@ -1230,6 +1230,52 @@ roff_node_delete(struct roff_man *man, struct roff_node *n)
 	roff_node_free(n);
 }
 
+void
+deroff(char **dest, const struct roff_node *n)
+{
+	char	*cp;
+	size_t	 sz;
+
+	if (n->type != ROFFT_TEXT) {
+		for (n = n->child; n != NULL; n = n->next)
+			deroff(dest, n);
+		return;
+	}
+
+	/* Skip leading whitespace and escape sequences. */
+
+	cp = n->string;
+	while (*cp != '\0') {
+		if ('\\' == *cp) {
+			cp++;
+			mandoc_escape((const char **)&cp, NULL, NULL);
+		} else if (isspace((unsigned char)*cp))
+			cp++;
+		else
+			break;
+	}
+
+	/* Skip trailing whitespace. */
+
+	for (sz = strlen(cp); sz; sz--)
+		if ( ! isspace((unsigned char)cp[sz-1]))
+			break;
+
+	/* Skip empty strings. */
+
+	if (sz == 0)
+		return;
+
+	if (*dest == NULL) {
+		*dest = mandoc_strndup(cp, sz);
+		return;
+	}
+
+	mandoc_asprintf(&cp, "%s %*s", *dest, (int)sz, cp);
+	free(*dest);
+	*dest = cp;
+}
+
 /* --- main functions of the roff parser ---------------------------------- */
 
 /*