- Account for the fact that concat and pick-first-value both use lisp-style

  lists, which end in a nil.

diff --git a/common/tree.c b/common/tree.c
index 7ad5b5d919323cdcc794a43c5b133500f3176251..55bc6b464858de7da926ffb33d3443c6526b1f61 100644 (file)
--- a/common/tree.c
+++ b/common/tree.c
@@ -22,7 +22,7 @@
 
 #ifndef lint
 static char copyright[] =
-"$Id: tree.c,v 1.50 1999/09/22 17:27:01 mellon Exp $ Copyright (c) 1995, 1996, 1997, 1998 The Internet Software Consortium.  All rights reserved.\n";
+"$Id: tree.c,v 1.51 1999/09/24 19:04:30 mellon Exp $ Copyright (c) 1995, 1996, 1997, 1998 The Internet Software Consortium.  All rights reserved.\n";
 #endif /* not lint */
 
 #include "dhcpd.h"
@@ -1912,6 +1912,8 @@ int write_expression (file, expr, col, indent)
              concat_again:
                col = write_expression (file, e -> data.concat [0],
                                        col, scol);
+               if (!e -> data.concat [1])
+                       goto no_concat_cdr;
                col = token_print_indent (file, col, scol, "", " ", ",");
                if (e -> data.concat [1] -> op == expr_concat) {
                        e = e -> data.concat [1];
@@ -1919,6 +1921,7 @@ int write_expression (file, expr, col, indent)
                }
                col = write_expression (file, e -> data.concat [1],
                                        col, scol);
+             no_concat_cdr:
                col = token_print_indent (file, col, indent, "", "", ")");
                break;
 
@@ -2121,6 +2124,14 @@ int write_expression (file, expr, col, indent)
                col = write_expression (file,
                                        e -> data.pick_first_value.car,
                                        col, scol);
+               /* We're being very lisp-like right now - instead of
+                   representing this expression as (first middle . last) we're
+                   representing it as (first middle last), which means that the
+                   tail cdr is always nil.  Apologies to non-wisp-lizards - may
+                   this obscure way of describing the problem motivate you to
+                   learn more about the one true computing language. */
+               if (!e -> data.pick_first_value.cdr)
+                       goto no_pick_cdr;
                col = token_print_indent (file, col, scol, "", " ",
                                          ",");
                if (e -> data.pick_first_value.cdr -> op ==
@@ -2131,6 +2142,7 @@ int write_expression (file, expr, col, indent)
                col = write_expression (file,
                                        e -> data.pick_first_value.cdr,
                                        col, scol);
+             no_pick_cdr:
                col = token_print_indent (file, col, indent, "", "",
                                          ")");
                break;