BFD: Fix build when BFD is disabled

Move bfd_opts grammar inside BFD parser code to avoid dependences between
nest and BFD grammars, which breaks when BFD build is disabled.

Add dummy bfd_opts grammar rule, so protocols can use this nonterminal
even with BFD disabled.

Thanks to Yuri Honegger for the bugreport.

nest/config.Y

@@ -124,7 +124,6 @@ CF_KEYWORDS(BGP, PASSWORDS, DESCRIPTION)
 CF_KEYWORDS(RELOAD, IN, OUT, MRTDUMP, MESSAGES, RESTRICT, MEMORY, IGP_METRIC, CLASS, DSCP)
 CF_KEYWORDS(TIMEFORMAT, ISO, SHORT, LONG, ROUTE, PROTOCOL, BASE, LOG, S, MS, US)
 CF_KEYWORDS(GRACEFUL, RESTART, WAIT, MAX, AS)
-CF_KEYWORDS(MIN, IDLE, RX, TX, INTERVAL, MULTIPLIER, PASSIVE)
 CF_KEYWORDS(CHECK, LINK)
 CF_KEYWORDS(SORTED, TRIE, MIN, MAX, SETTLE, TIME, GC, THRESHOLD, PERIOD)
 CF_KEYWORDS(MPLS_LABEL, MPLS_POLICY, MPLS_CLASS)
@@ -602,51 +601,8 @@ password_item_end:
 };
 
 
-/* BFD options */
-
-bfd_item:
-   INTERVAL expr_us { this_bfd_opts->min_rx_int = this_bfd_opts->min_tx_int = $2; }
- | MIN RX INTERVAL expr_us { this_bfd_opts->min_rx_int = $4; }
- | MIN TX INTERVAL expr_us { this_bfd_opts->min_tx_int = $4; }
- | IDLE TX INTERVAL expr_us { this_bfd_opts->idle_tx_int = $4; }
- | MULTIPLIER expr { this_bfd_opts->multiplier = $2; }
- | PASSIVE bool { this_bfd_opts->passive = $2; this_bfd_opts->passive_set = 1; }
- | GRACEFUL { this_bfd_opts->mode = BGP_BFD_GRACEFUL; }
- | AUTHENTICATION bfd_auth_type { this_bfd_opts->auth_type = $2; }
- | password_list {}
- ;
-
-bfd_items:
-   /* empty */
- | bfd_items bfd_item ';'
- ;
-
-bfd_opts_start:
-{ reset_passwords(); } ;
-
-bfd_opts_end:
-{
-  this_bfd_opts->passwords = get_passwords();
-
-  if (!this_bfd_opts->auth_type != !this_bfd_opts->passwords)
-    cf_warn("Authentication and password options should be used together");
-
-  if (this_bfd_opts->passwords)
-  {
-    struct password_item *pass;
-    WALK_LIST(pass, *this_bfd_opts->passwords)
-    {
-      if (pass->alg)
-        cf_error("Password algorithm option not available in BFD protocol");
-
-      pass->alg = bfd_auth_type_to_hash_alg[this_bfd_opts->auth_type];
-    }
-  }
-};
-
-bfd_opts:
-   bfd_opts_start '{' bfd_items '}' bfd_opts_end
- ;
+/* BFD options - just dummy rule, rest in proto/bfd/config.Y */
+bfd_opts: '{' INVALID_TOKEN '}';
 
 
 /* Core commands */

proto/bfd/config.Y

@@ -183,6 +183,52 @@ bfd_neighbor: ipa bfd_neigh_iface bfd_neigh_local bfd_neigh_multihop
 };
 
 
+/* BFD options */
+
+bfd_item:
+   INTERVAL expr_us { this_bfd_opts->min_rx_int = this_bfd_opts->min_tx_int = $2; }
+ | MIN RX INTERVAL expr_us { this_bfd_opts->min_rx_int = $4; }
+ | MIN TX INTERVAL expr_us { this_bfd_opts->min_tx_int = $4; }
+ | IDLE TX INTERVAL expr_us { this_bfd_opts->idle_tx_int = $4; }
+ | MULTIPLIER expr { this_bfd_opts->multiplier = $2; }
+ | PASSIVE bool { this_bfd_opts->passive = $2; this_bfd_opts->passive_set = 1; }
+ | GRACEFUL { this_bfd_opts->mode = BGP_BFD_GRACEFUL; }
+ | AUTHENTICATION bfd_auth_type { this_bfd_opts->auth_type = $2; }
+ | password_list {}
+ ;
+
+bfd_items:
+   /* empty */
+ | bfd_items bfd_item ';'
+ ;
+
+bfd_opts_start:
+{ reset_passwords(); } ;
+
+bfd_opts_end:
+{
+  this_bfd_opts->passwords = get_passwords();
+
+  if (!this_bfd_opts->auth_type != !this_bfd_opts->passwords)
+    cf_warn("Authentication and password options should be used together");
+
+  if (this_bfd_opts->passwords)
+  {
+    struct password_item *pass;
+    WALK_LIST(pass, *this_bfd_opts->passwords)
+    {
+      if (pass->alg)
+        cf_error("Password algorithm option not available in BFD protocol");
+
+      pass->alg = bfd_auth_type_to_hash_alg[this_bfd_opts->auth_type];
+    }
+  }
+};
+
+bfd_opts:
+  '{' bfd_opts_start bfd_items '}' bfd_opts_end;
+
+
 CF_CLI_HELP(SHOW BFD, ..., [[Show information about BFD protocol]]);
 
 CF_CLI_HELP(SHOW BFD SESSIONS, ..., [[Show information about BFD sessions]]);