Improve statistics test cases

2 files changed, 80 insertions, 44 deletions

diff --git a/lib/diameter/src/base/diameter_stats.erl b/lib/diameter/src/base/diameter_stats.erl
index 8d4b456bd2..70727d068e 100644
--- a/lib/diameter/src/base/diameter_stats.erl
+++ b/lib/diameter/src/base/diameter_stats.erl
@@ -25,8 +25,8 @@
 
 -behaviour(gen_server).
 
--export([reg/1, reg/2,
-         incr/1, incr/3,
+-export([reg/2, reg/1,
+         incr/3, incr/1,
          read/1,
          flush/1]).
 
@@ -96,9 +96,10 @@ reg(Ref) ->
 %% ---------------------------------------------------------------------------
 
 -spec incr(counter(), ref(), integer())
-   -> integer().
+   -> integer() | false.
 
-incr(Ctr, Ref, N) ->
+incr(Ctr, Ref, N)
+  when is_integer(N) ->
     update_counter({Ctr, Ref}, N).
 
 incr(Ctr) ->
@@ -177,6 +178,9 @@ handle_call(state, _, State) ->
 handle_call(uptime, _, #state{id = Time} = State) ->
     {reply, diameter_lib:now_diff(Time), State};
 
+handle_call({incr, T}, _, State) ->
+    {reply, update_counter(T), State};
+
 handle_call({reg, Pid, Ref}, _From, State) ->
     B = ets:insert_new(?TABLE, {Pid, Ref}),
     B andalso erlang:monitor(process, Pid),
@@ -193,10 +197,6 @@ handle_call(Req, From, State) ->
 %% # handle_cast/2
 %% ----------------------------------------------------------
 
-handle_cast({incr, Rec}, State) ->
-    update_counter(Rec),
-    {noreply, State};
-
 handle_cast(Msg, State) ->
     ?UNEXPECTED([Msg]),
     {noreply, State}.
@@ -246,21 +246,22 @@ fold(Ref, L) ->
 
 %% update_counter/2
 %%
-%% From an arbitrary process. Cast to the server process to insert a
+%% From an arbitrary process. Call to the server process to insert a
 %% new element if the counter doesn't exists so that two processes
-%% don't do so simultaneously.
+%% don't insert simultaneously.
 
 update_counter(Key, N) ->
     try
         ets:update_counter(?TABLE, Key, N)
     catch
         error: badarg ->
-            cast({incr, {Key, N}})
+            call({incr, {Key, N}})
     end.
 
 %% update_counter/1
 %%
-%% From the server process.
+%% From the server process, when update_counter/2 failed due to a
+%% non-existent entry.
 
 update_counter({{_Ctr, Ref} = Key, N} = T) ->
     try
@@ -268,7 +269,7 @@ update_counter({{_Ctr, Ref} = Key, N} = T) ->
     catch
         error: badarg ->
             (not is_pid(Ref) orelse ets:member(?TABLE, Ref))
-                andalso insert(T)
+                andalso begin insert(T), N end
     end.
 
 insert(T) ->
@@ -280,11 +281,6 @@ lookup(Key) ->
 delete(Objs) ->
     lists:foreach(fun({K,_}) -> ets:delete(?TABLE, K) end, Objs).
 
-%% cast/1
-
-cast(Msg) ->
-    gen_server:cast(?SERVER, Msg).
-
 %% call/1
 
 call(Request) ->
diff --git a/lib/diameter/test/diameter_stats_SUITE.erl b/lib/diameter/test/diameter_stats_SUITE.erl
index e7807fd360..4a93d4f748 100644
--- a/lib/diameter/test/diameter_stats_SUITE.erl
+++ b/lib/diameter/test/diameter_stats_SUITE.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 2010-2011. All Rights Reserved.
+%% Copyright Ericsson AB 2010-2012. All Rights Reserved.
 %%
 %% The contents of this file are subject to the Erlang Public License,
 %% Version 1.1, (the "License"); you may not use this file except in
@@ -30,11 +30,12 @@
          end_per_suite/1]).
 
 %% testcases
--export([an/1,
-         twa/1]).
+-export([reg/1,
+         incr/1,
+         read/1,
+         flush/1]).
 
 -define(stat, diameter_stats).
--define(util, diameter_util).
 
 %% ===========================================================================
 
@@ -49,8 +50,10 @@ groups() ->
     [{all, [], tc()}].
 
 tc() ->
-    [an,
-     twa].
+    [reg,
+     incr,
+     read,
+     flush].
 
 init_per_suite(Config) ->
     ok = diameter:start(),
@@ -61,25 +64,62 @@ end_per_suite(_Config) ->
 
 %% ===========================================================================
 
-an(_) ->
-    Ref = {'_', make_ref()},
+reg(_) ->
+    Ref = '$1',
     true = ?stat:reg(Ref),
-    true = ?stat:reg(Ref),  %% duplicate
-    ok = ?stat:incr(x),
-    ok = ?stat:incr(x, Ref),
-    ok = ?stat:incr(y, 2),
-    ok = ?stat:incr(y, Ref),
-    %% Flushing a pid flushes even stats on the registered reference.
-    [{x,2},{y,3}] = lists:sort(?stat:flush()),
-    [] = ?stat:flush(Ref),
-    [] = ?stat:flush().
-
-twa(_) ->
+    false = ?stat:reg(Ref).  %% duplicate
+
+incr(_) ->    
+    Ref = '_',
+    Ctr = x,
+    false = ?stat:incr(Ctr),      %% not registered,
+    1 = ?stat:incr(Ctr, Ref, 1),  %% only pids need register
+    true = ?stat:reg(Ref),
+    spawn(fun() ->
+                  true = ?stat:reg(Ref),
+                  2 = ?stat:incr(Ctr, self(), 2)
+          end),
+    ok = fold(Ctr, Ref, 3),  %% folded
+    ?stat:flush([self(), Ref]).
+
+read(_) ->
+    Ref = make_ref(),
+    C1 = {a,b},
+    C2 = {b,a},
+    true = ?stat:reg(Ref),
+    1 = ?stat:incr(C1),
+    1 = ?stat:incr(C2),
+    2 = ?stat:incr(C1),
+    7 = ?stat:incr(C1, Ref, 7),
+    Self = self(),
+    [{Ref,  [{C1,7}]}, {Self, [{C1,2}, {C2,1}]}]
+        = lists:sort(?stat:read([self(), Ref, make_ref()])),
+    [] = ?stat:read([]),
+    [] = ?stat:read([make_ref()]),
+    ?stat:flush([self(), Ref, make_ref()]).
+
+flush(_) ->
     Ref = make_ref(),
-    ok = ?stat:incr(x, 8),
-    ok = ?stat:incr(x, Ref, 7),
-    %% Flushing a reference doesn't affect registered pids.
-    [{x,7}] = ?stat:flush(Ref),
-    [] = ?stat:flush(Ref),
-    [{x,8}] = ?stat:flush(),
-    [] = ?stat:flush().
+    Ctr = '_',
+    true = ?stat:reg(Ref),
+    1 = ?stat:incr(Ctr),
+    3 = ?stat:incr(Ctr, self(), 2),
+    2 = ?stat:incr(Ctr, Ref, 2),
+    Self = self(),
+    [{Self, [{Ctr, 3}]}] = ?stat:flush([self()]),
+    1 = ?stat:incr(Ctr),
+    [{Ref,  [{Ctr, 2}]}] = ?stat:flush([Ref]),
+    [{Self, [{Ctr, 1}]}] = ?stat:flush([self()]),
+    [] = ?stat:flush([self(), Ref]).
+
+%% ===========================================================================
+
+%% Keep incremented until a fold results in the specified value.
+fold(Ctr, Ref, N) ->
+    case ?stat:incr(Ctr, Ref, 0) of
+        N ->
+            ok;
+        M when M < N ->
+            erlang:yield(),
+            fold(Ctr, Ref, N)
+    end.