1 files changed, 118 insertions, 0 deletions
diff --git a/lib/debugger/src/dbg_debugged.erl b/lib/debugger/src/dbg_debugged.erl
new file mode 100644
index 0000000000..b56ebef14a
--- /dev/null
+++ b/lib/debugger/src/dbg_debugged.erl
@@ -0,0 +1,118 @@
+%%
+%% %CopyrightBegin%
+%% 
+%% Copyright Ericsson AB 1998-2009. 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
+%% compliance with the License. You should have received a copy of the
+%% Erlang Public License along with this software. If not, it can be
+%% retrieved online at http://www.erlang.org/.
+%% 
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and limitations
+%% under the License.
+%% 
+%% %CopyrightEnd%
+%%
+-module(dbg_debugged).
+
+%% External exports
+-export([eval/3]).
+
+%%====================================================================
+%% External exports
+%%====================================================================
+
+%%--------------------------------------------------------------------
+%% eval(Mod, Func, Args) -> Value
+%% Main entry point from external (non-interpreted) code.
+%% Called via the error handler.
+%%--------------------------------------------------------------------
+eval(Mod, Func, Args) ->
+    SaveStacktrace = erlang:get_stacktrace(),
+    Meta = dbg_ieval:eval(Mod, Func, Args),
+    Mref = erlang:monitor(process, Meta),
+    msg_loop(Meta, Mref, SaveStacktrace).
+
+%%====================================================================
+%% Internal functions
+%%====================================================================
+
+msg_loop(Meta, Mref, SaveStacktrace) ->
+    receive
+
+	%% Evaluated function has returned a value
+	{sys, Meta, {ready, Val}} ->
+	    demonitor(Mref),
+
+	    %% Restore original stacktrace and return the value
+	    try erlang:raise(throw, stack, SaveStacktrace)
+	    catch
+		throw:stack ->
+		    case Val of
+			{dbg_apply,M,F,A} ->
+			    apply(M, F, A);
+			_ ->
+			    Val
+		    end
+	    end;
+
+	%% Evaluated function raised an (uncaught) exception
+	{sys, Meta, {exception,{Class,Reason,Stacktrace}}} ->
+	    demonitor(Mref),
+
+	    %% ...raise the same exception
+	    erlang:error(erlang:raise(Class, Reason, Stacktrace), 
+			 [Class,Reason,Stacktrace]);
+
+	%% Meta is evaluating a receive, must be done within context
+	%% of real (=this) process
+	{sys, Meta, {'receive',Msg}} ->
+	    receive Msg -> Meta ! {self(), rec_acked} end,
+	    msg_loop(Meta, Mref, SaveStacktrace);
+
+	%% Meta needs something evaluated within context of real process
+	{sys, Meta, {command, Command, Stacktrace}} ->
+	    Reply = handle_command(Command, Stacktrace),
+	    Meta ! {sys, self(), Reply},
+	    msg_loop(Meta, Mref, SaveStacktrace);
+
+	%% Meta has terminated
+	%% Must be due to int:stop() (or -heaven forbid- a debugger bug)
+	{'DOWN', Mref, _, _, Reason} ->
+
+	    %% Restore original stacktrace and return a dummy value
+	    try erlang:raise(throw, stack, SaveStacktrace)
+	    catch
+		throw:stack ->
+		    {interpreter_terminated, Reason}
+	    end
+    end.
+
+handle_command(Command, Stacktrace) ->
+    try reply(Command)
+    catch Class:Reason ->
+	    Stacktrace2 = stacktrace_f(erlang:get_stacktrace()),
+	    {exception, {Class,Reason,Stacktrace2++Stacktrace}}
+    end.
+
+reply({apply,M,F,As}) ->
+    {value, erlang:apply(M,F,As)};
+reply({eval,Expr,Bs}) ->
+    erl_eval:expr(Expr, Bs). % {value, Value, Bs2}
+
+%% Demonitor and delete message from inbox
+%%
+demonitor(Mref) ->
+    erlang:demonitor(Mref),
+    receive {'DOWN',Mref,_,_,_} -> ok
+    after 0 -> ok
+    end.
+
+%% Fix stacktrace - keep all above call to this module.
+%%
+stacktrace_f([]) -> [];
+stacktrace_f([{?MODULE,_,_}|_]) -> [];
+stacktrace_f([F|S]) -> [F|stacktrace_f(S)].