From 7ccb36d3308ef57d340e663f0cabd24663f4f62a Mon Sep 17 00:00:00 2001
From: Ondrej Zajicek <santiago@crfreenet.org>
Date: Wed, 2 Oct 2013 14:57:29 +0200
Subject: [PATCH] Implements C.len operator for clist and eclist types.

Thanks to Sergey Popovich for the original patch.
---
 doc/bird.sgml    | 2 ++
 filter/filter.c  | 4 +++-
 filter/test.conf | 5 +++--
 nest/attrs.h     | 3 +++
 4 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/doc/bird.sgml b/doc/bird.sgml
index f43eb4bf..050acf33 100644
--- a/doc/bird.sgml
+++ b/doc/bird.sgml
@@ -1077,6 +1077,8 @@ incompatible with each other (that is to prevent you from shooting in the foot).
 	  no literals of this type. There are three special operators on
 	  clists:
 
+	  <cf><m/C/.len</cf> returns the length of clist <m/C/.
+
           <cf>add(<m/C/,<m/P/)</cf> adds pair (or quad) <m/P/ to clist
 	  <m/C/ and returns the result.  If item <m/P/ is already in
 	  clist <m/C/, it does nothing. <m/P/ may also be a clist,
diff --git a/filter/filter.c b/filter/filter.c
index 50e3f403..b01933f7 100644
--- a/filter/filter.c
+++ b/filter/filter.c
@@ -1067,7 +1067,9 @@ interpret(struct f_inst *what)
     switch(v1.type) {
     case T_PREFIX: res.val.i = v1.val.px.len; break;
     case T_PATH:   res.val.i = as_path_getlen(v1.val.ad); break;
-    default: runtime( "Prefix or path expected" );
+    case T_CLIST:  res.val.i = int_set_get_size(v1.val.ad); break;
+    case T_ECLIST: res.val.i = ec_set_get_size(v1.val.ad); break;
+    default: runtime( "Prefix, path, clist or eclist expected" );
     }
     break;
   case P('c','p'):	/* Convert prefix to ... */
diff --git a/filter/test.conf b/filter/test.conf
index b8f706cb..03b09c30 100644
--- a/filter/test.conf
+++ b/filter/test.conf
@@ -142,10 +142,10 @@ eclist el2;
 	l = add( l, (3,5) );
 	l2 = filter( l, [(3,*)] );
 	l = delete( l, [(3,2..4)] );
-	print "Community list (1,2) (3,1) (3,5) ", l;
+	print "Community list (1,2) (3,1) (3,5) ", l, " len: ", l.len;
 	l = add( l, (3,2) );
 	l = add( l, (4,5) );
-	print "Community list (1,2) (3,1) (3,2) (3,5) (4,5) ", l;
+	print "Community list (1,2) (3,1) (3,2) (3,5) (4,5) ", l, " len: ", l.len;
 	print "Should be true: ", l ~ [(*,2)], " ", l ~ [(*,5)], " ", l ~ [(*, one)];
 	print "Should be false: ", l ~ [(*,3)], " ", l ~ [(*,(one+6))], " ", l ~ [(*, (one+one+one))];
 	l = delete( l, [(*,(one+onef(3)))] );
@@ -168,6 +168,7 @@ eclist el2;
 	el = add(el, (ro, 11.21.31.41.mask(16), 200));
 	print "EC list (rt, 10, 20) (ro, 10.20.30.40, 100) (ro, 11.21.0.0, 200):";
 	print el;
+	print "EC len: ", el.len;
 	el = delete(el, (rt, 10, 20));
 	el = delete(el, (rt, 10, 30));
 	el = add(el, (unknown 2, ten, 1));
diff --git a/nest/attrs.h b/nest/attrs.h
index 44a23e18..a0dae221 100644
--- a/nest/attrs.h
+++ b/nest/attrs.h
@@ -69,6 +69,9 @@ int as_path_match(struct adata *path, struct f_path_mask *mask);
 static inline int int_set_get_size(struct adata *list)
 { return list->length / 4; }
 
+static inline int ec_set_get_size(struct adata *list)
+{ return list->length / 8; }
+
 static inline u32 *int_set_get_data(struct adata *list)
 { return (u32 *) list->data; }