Compile regular expressions that will be matched multiple times

1 files changed, 23 insertions, 7 deletions

diff --git a/src/rabbit_policy.erl b/src/rabbit_policy.erl
index 3ed0734b..3400a7d5 100644
--- a/src/rabbit_policy.erl
+++ b/src/rabbit_policy.erl
@@ -81,11 +81,12 @@ notify_clear(VHost, <<"policy">>, _Name) ->
 %%----------------------------------------------------------------------------
 
 list(VHost) ->
-    [[{<<"name">>, pget(key, P)} | pget(value, P)]
-     || P <- rabbit_runtime_parameters:list(VHost, <<"policy">>)].
+    lists:sort(fun sort_pred/2,
+               [[{<<"name">>, pget(key, P)} | pget(value, P)]
+                || P <- rabbit_runtime_parameters:list(VHost, <<"policy">>)]).
 
 update_policies(VHost) ->
-    Policies = list(VHost),
+    Policies = add_compile(list(VHost)),
     {Xs, Qs} = rabbit_misc:execute_mnesia_transaction(
                  fun() ->
                          {[update_exchange(X, Policies) ||
@@ -98,7 +99,7 @@ update_policies(VHost) ->
     ok.
 
 update_exchange(X = #exchange{name = XName, policy = OldPolicy}, Policies) ->
-    NewPolicy = match(XName, Policies),
+    NewPolicy = strip_compile(match(XName, Policies)),
     case NewPolicy of
         OldPolicy -> no_change;
         _         -> rabbit_exchange:update(
@@ -107,7 +108,7 @@ update_exchange(X = #exchange{name = XName, policy = OldPolicy}, Policies) ->
     end.
 
 update_queue(Q = #amqqueue{name = QName, policy = OldPolicy}, Policies) ->
-    NewPolicy = match(QName, Policies),
+    NewPolicy = strip_compile(match(QName, Policies)),
     case NewPolicy of
         OldPolicy -> no_change;
         _         -> rabbit_amqqueue:update(
@@ -123,19 +124,34 @@ notify({Q1 = #amqqueue{}, Q2 = #amqqueue{}}) ->
     rabbit_amqqueue:policy_changed(Q1, Q2).
 
 match(Name, Policies) ->
-    case lists:sort(fun sort_pred/2, [P || P <- Policies, matches(Name, P)]) of
+    case lists:filter(fun (P) -> matches(Name, P) end, Policies) of
         []               -> undefined;
         [Policy | _Rest] -> Policy
     end.
 
 matches(#resource{name = Name}, Policy) ->
     case re:run(binary_to_list(Name),
-                binary_to_list(pget(<<"pattern">>, Policy)),
+                pattern_pref(Policy),
                 [{capture, none}]) of
         nomatch -> false;
         match   -> true
     end.
 
+add_compile(Policies) ->
+    [ begin
+        {ok, MP} = re:compile(binary_to_list(pget(<<"pattern">>, Policy))),
+        [{<<"compiled">>, MP} | Policy]
+      end || Policy <- Policies ].
+
+strip_compile(undefined) -> undefined;
+strip_compile(Policy)    -> proplists:delete(<<"compiled">>, Policy).
+
+pattern_pref(Policy) ->
+    case pget(<<"compiled">>, Policy) of
+        undefined -> binary_to_list(pget(<<"pattern">>, Policy));
+        Compiled  -> Compiled
+    end.
+
 sort_pred(A, B) ->
     pget(<<"priority">>, A) >= pget(<<"priority">>, B).