Merge branch 'anders/diameter/pool/OTP-12428' into maint

* anders/diameter/pool/OTP-12428:
  Fix SCTP match blunder in suites
  Be backwards compatible with diameter_sctp listener state
  Add gen_tcp testcase that fails sporadically
  Simplify transport suite
  Remove (ancient) dead code
  Don't orphan slave nodes in example suite
  Refresh example code
  Improve language consistency in diameter(1)
  Add pool suite to test transport_opt() pool_size
  Adapt tcp/sctp transport modules for pool_size > 1
  Add transport_opt() pool_size

1 files changed, 31 insertions, 0 deletions

diff --git a/lib/diameter/src/base/diameter_lib.erl b/lib/diameter/src/base/diameter_lib.erl
index b5f1ae3937..cd88619b66 100644
--- a/lib/diameter/src/base/diameter_lib.erl
+++ b/lib/diameter/src/base/diameter_lib.erl
@@ -31,6 +31,8 @@
          spawn_opts/2,
          wait/1,
          fold_tuple/3,
+         fold_n/3,
+         for_n/2,
          log/4]).
 
 %% ---------------------------------------------------------------------------
@@ -292,6 +294,35 @@ ft(Value, {Idx, T}) ->
     setelement(Idx, T, Value).
 
 %% ---------------------------------------------------------------------------
+%% # fold_n/3
+%% ---------------------------------------------------------------------------
+
+-spec fold_n(F, Acc0, N)
+   -> term()
+ when F    :: fun((non_neg_integer(), term()) -> term()),
+      Acc0 :: term(),
+      N    :: non_neg_integer().
+
+fold_n(F, Acc, N)
+  when is_integer(N), 0 < N ->
+    fold_n(F, F(N, Acc), N-1);
+
+fold_n(_, Acc, _) ->
+    Acc.
+
+%% ---------------------------------------------------------------------------
+%% # for_n/2
+%% ---------------------------------------------------------------------------
+
+-spec for_n(F, N)
+   -> non_neg_integer()
+ when F :: fun((non_neg_integer()) -> term()),
+      N :: non_neg_integer().
+
+for_n(F, N) ->
+    fold_n(fun(M,A) -> F(M), A+1 end, 0, N).
+
+%% ---------------------------------------------------------------------------
 %% # log/4
 %%
 %% Called to have something to trace on for happenings of interest.