Merge pull request #28 from stritzinger/otp-21-stacktrace-compatibility

Add compatibility for OTP 21+ stack traces

src/cluster_info.erl

@@ -44,6 +44,8 @@
 %% Really useful but ugly hack.
 -export([capture_io/2]).
 
+-include("stacktrace.hrl").
+
 -type dump_option() :: {'modules', [atom()]}.
 -type dump_return() :: 'ok' | 'error'.
 -type filename()    :: string().
@@ -125,9 +127,9 @@ dump_node(Node, Path, Opts) when is_atom(Node), is_list(Path) ->
     MRef = monitor(process, Remote),
     try
         ok = collect_remote_info(Remote, FH)
-    catch X:Y ->
+    catch ?_exception_(X, Y, StackToken) ->
         io:format("Error: ~P ~P at ~p\n",
-            [X, 20, Y, 20, erlang:get_stacktrace()]),
+            [X, 20, Y, 20, ?_get_stacktrace_(StackToken)]),
         error
     after
         demonitor(MRef, [flush]),
@@ -272,9 +274,9 @@ dump_local_info(CPid, Opts) ->
                                           [Name, node()]),
                           format_noescape(CPid, "<pre>\n", []),
                           Fun(CPid)
-                      catch X:Y ->
+                      catch ?_exception_(X, Y, StackToken) ->
                               format(CPid, "Error in ~p: ~p ~p at ~p\n",
-                                     [Name, X, Y, erlang:get_stacktrace()])
+                                     [Name, X, Y, ?_get_stacktrace_(StackToken)])
                       after
                           format_noescape(CPid, "</pre>\n", []),
                           format_noescape(CPid, "\n",[])

src/cluster_info_basic.erl

@@ -35,6 +35,8 @@
          loaded_modules/1, memory_hogs/2, non_zero_mailboxes/1, port_info/1,
          registered_names/1, time_and_date/1, timer_status/1]).
 
+-include("stacktrace.hrl").
+
 -ifdef(TEST).
 -include_lib("eunit/include/eunit.hrl").
 -endif.
@@ -84,9 +86,9 @@ application_info(C) ->
          cluster_info:format(C, " ~p\n\n", [application:get_all_key(App)]),
          cluster_info:format(C, " Application:get_all_env(~p):\n", [App]),
          cluster_info:format(C, " ~p\n\n", [application:get_all_env(App)])
-     catch X:Y ->
+     catch ?_exception_(X, Y, StackToken) ->
              cluster_info:format(C, "Error for ~p: ~p ~p at ~p\n",
-                                 [App, X, Y, erlang:get_stacktrace()])
+                                 [App, X, Y, ?_get_stacktrace_(StackToken)])
      end || App <- lists:sort([A || {A, _, _} <- application:which_applications()])].
 
 capture_ets_i(C) ->
@@ -174,9 +176,9 @@ loaded_modules(C) ->
     [try
          cluster_info:format(C, " Module ~p:\n", [Mod]),
          cluster_info:format(C, " ~p\n\n", [Mod:module_info()])
-     catch X:Y ->
+     catch ?_exception_(X, Y, StackToken) ->
              cluster_info:format(C, "Error for ~p: ~p ~p at ~p\n",
-                                 [Mod, X, Y, erlang:get_stacktrace()])
+                                 [Mod, X, Y, ?_get_stacktrace_(StackToken)])
      end || Mod <- lists:sort([M || {M, _} <- code:all_loaded()])].
 
 memory_hogs(C, Num) ->

src/stacktrace.hrl

@@ -0,0 +1,33 @@
+%% Originating from Quviq AB
+%% Fix to make Erlang programs compile on both OTP20 and OTP21.
+%%
+%% Get the stack trace in a way that is backwards compatible. Luckily
+%% OTP_RELEASE was introduced in the same version as the new preferred way of
+%% getting the stack trace. A _catch_/2 macro is provided for consistency in
+%% cases where the stack trace is not needed.
+%%
+%% Example use:
+%%    try f(...)
+%%    catch
+%%         ?_exception_(_, Reason, StackToken) ->
+%%             case Reason of
+%%                 {fail, Error} -> ok;
+%%                 _             -> {'EXIT', Reason, ?_get_stacktrace_(StackToken)}
+%%             end
+%%     end,
+
+-ifdef(OTP_RELEASE). %% This implies 21 or higher
+-define(_exception_(Class, Reason, StackToken), Class:Reason:StackToken).
+-define(_get_stacktrace_(StackToken), StackToken).
+-define(_current_stacktrace_(),
+        try
+            exit('$get_stacktrace')
+        catch
+            exit:'$get_stacktrace':__GetCurrentStackTrace ->
+                __GetCurrentStackTrace
+        end).
+-else.
+-define(_exception_(Class, Reason, _), Class:Reason).
+-define(_get_stacktrace_(_), erlang:get_stacktrace()).
+-define(_current_stacktrace_(), erlang:get_stacktrace()).
+-endif.