aboutsummaryrefslogblamecommitdiffstats
path: root/lib/test_server/src/test_server_sup.erl
blob: 4a7804a482c761664210c4e0b1b5d445bf54f577 (plain) (tree)
1
2
3
4
5
6
7
8
9
10
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496

                   


                                                        




                                                                      
  



                                                                         
  






                                                                      
                                                                                  











                                                                       
                                        




                                                                

                                                               

                          


                                  
                                


                                                                       


























































































































































































































































































































































































































































                                                                                 

                                              








                                                           
                                                       











                                                                       



















































































































                                                                                          
%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1998-2010. 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%
%%

%%%-------------------------------------------------------------------
%%% Purpose: Test server support functions.
%%%-------------------------------------------------------------------
-module(test_server_sup).
-export([timetrap/2, timetrap/3, timetrap_cancel/1, capture_get/1, messages_get/1,
	 timecall/3, call_crash/5, app_test/2, check_new_crash_dumps/0,
	 cleanup_crash_dumps/0, crash_dump_dir/0, tar_crash_dumps/0,
	 get_username/0, get_os_family/0, 
	 hostatom/0, hostatom/1, hoststr/0, hoststr/1,
	 framework_call/2,framework_call/3,
	 format_loc/1, package_str/1, package_atom/1,
	 call_trace/1]).
-include("test_server_internal.hrl").
-define(crash_dump_tar,"crash_dumps.tar.gz").
-define(src_listing_ext, ".src.html").

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% timetrap(Timeout,Scale,Pid) -> Handle
%% Handle = term()
%%
%% Creates a time trap, that will kill the given process if the 
%% trap is not cancelled with timetrap_cancel/1, within Timeout
%% milliseconds.
%% Scale says if the time should be scaled up to compensate for
%% delays during the test (e.g. if cover is running).

timetrap(Timeout0, Pid) ->
    timetrap(Timeout0, true, Pid).

timetrap(Timeout0, Scale, Pid) ->
    process_flag(priority, max),
    Timeout = if not Scale -> Timeout0;
		 true -> test_server:timetrap_scale_factor() * Timeout0
	      end,
    receive
    after trunc(Timeout) ->
	    Line = test_server:get_loc(Pid),
	    Mon = erlang:monitor(process, Pid),
	    Trap = 
		case get(test_server_init_or_end_conf) of
		    undefined ->
			{timetrap_timeout,trunc(Timeout),Line};
		    InitOrEnd ->
			{timetrap_timeout,trunc(Timeout),Line,InitOrEnd}
		end,
	    exit(Pid,Trap),
	    receive
		{'DOWN', Mon, process, Pid, _} ->
		    ok
	    after 10000 ->
		    %% Pid is probably trapping exits, hit it harder...
		    catch error_logger:warning_msg("Testcase process ~p not "
						   "responding to timetrap "
						   "timeout:~n"
						   "  ~p.~n"
						   "Killing testcase...~n",
						   [Pid, Trap]),
		    exit(Pid, kill)
	    end
    end.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% timetrap_cancel(Handle) -> ok
%% Handle = term()
%%
%% Cancels a time trap.

timetrap_cancel(Handle) ->
    unlink(Handle),
    MonRef = erlang:monitor(process, Handle),
    exit(Handle, kill),
    receive {'DOWN',MonRef,_,_,_} -> ok after 2000 -> ok end.

capture_get(Msgs) ->
    receive
	{captured,Msg} ->
	    capture_get([Msg|Msgs])
    after 0 ->
	    lists:reverse(Msgs)
    end.


messages_get(Msgs) ->
    receive
	Msg ->
	    messages_get([Msg|Msgs])
    after 0 ->
	    lists:reverse(Msgs)
    end.


timecall(M, F, A) ->
    Befor = erlang:now(),
    Val = apply(M, F, A),
    After = erlang:now(),
    Elapsed =
        (element(1,After)*1000000+element(2,After)+element(3,After)/1000000)-
        (element(1,Befor)*1000000+element(2,Befor)+element(3,Befor)/1000000),
    {Elapsed, Val}.



call_crash(Time,Crash,M,F,A) ->
    OldTrapExit = process_flag(trap_exit,true),
    Pid = spawn_link(M,F,A),
    Answer =
	receive
	    {'EXIT',Crash} ->
		ok;
	    {'EXIT',Pid,Crash} ->
		ok;
	    {'EXIT',_Reason} when Crash==any ->
		ok;
	    {'EXIT',Pid,_Reason} when Crash==any ->
		ok;
	    {'EXIT',Reason} ->
		test_server:format(12, "Wrong crash reason. Wanted ~p, got ~p.",
		      [Crash, Reason]),
		exit({wrong_crash_reason,Reason});
	    {'EXIT',Pid,Reason} ->
		test_server:format(12, "Wrong crash reason. Wanted ~p, got ~p.",
		      [Crash, Reason]),
		exit({wrong_crash_reason,Reason});
	    {'EXIT',OtherPid,Reason} when OldTrapExit == false ->
		exit({'EXIT',OtherPid,Reason})
	after do_trunc(Time) ->
		exit(call_crash_timeout)
	end,
    process_flag(trap_exit,OldTrapExit),
    Answer.

do_trunc(infinity) -> infinity;
do_trunc(T) -> trunc(T).


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% app_test/2
%%
%% Checks one applications .app file for obvious errors.
%% Checks..
%% * .. required fields
%% * .. that all modules specified actually exists
%% * .. that all requires applications exists
%% * .. that no module included in the application has export_all
%% * .. that all modules in the ebin/ dir is included
%%      (This only produce a warning, as all modules does not
%%       have to be included (If the `pedantic' option isn't used))
app_test(Application, Mode) ->
    case is_app(Application) of
	{ok, AppFile} ->
	    do_app_tests(AppFile, Application, Mode);
	Error ->
	    test_server:fail(Error)
    end.

is_app(Application) ->
    case file:consult(filename:join([code:lib_dir(Application),"ebin",
		   atom_to_list(Application)++".app"])) of
	{ok, [{application, Application, AppFile}] } ->
	    {ok, AppFile};
	_ ->
	    test_server:format(minor,
			       "Application (.app) file not found, "
			       "or it has very bad syntax.~n"),
	    {error, not_an_application}
    end.


do_app_tests(AppFile, AppName, Mode) ->
    DictList=
	[
	 {missing_fields, []},
	 {missing_mods, []},
	 {superfluous_mods_in_ebin, []},
	 {export_all_mods, []},
	 {missing_apps, []}
	],
    fill_dictionary(DictList),

    %% An appfile must (?) have some fields..
    check_fields([description, modules, registered, applications], AppFile),

    %% Check for missing and extra modules.
    {value, {modules, Mods}}=lists:keysearch(modules, 1, AppFile),
    EBinList=lists:sort(get_ebin_modnames(AppName)),
    {Missing, Extra} = common(lists:sort(Mods), EBinList),
    put(superfluous_mods_in_ebin, Extra),
    put(missing_mods, Missing),

    %% Check that no modules in the application has export_all.
    app_check_export_all(Mods),

    %% Check that all specified applications exists.
    {value, {applications, Apps}}=
	lists:keysearch(applications, 1, AppFile),
    check_apps(Apps),

    A=check_dict(missing_fields, "Inconsistent app file, "
	       "missing fields"),
    B=check_dict(missing_mods, "Inconsistent app file, "
	       "missing modules"),
    C=check_dict_tolerant(superfluous_mods_in_ebin, "Inconsistent app file, "
	       "Modules not included in app file.", Mode),
    D=check_dict(export_all_mods, "Inconsistent app file, "
	       "Modules have `export_all'."),
    E=check_dict(missing_apps, "Inconsistent app file, "
	       "missing applications."),

    erase_dictionary(DictList),
    case A+B+C+D+E of
	5 ->
	    ok;
	_ ->
	    test_server:fail()
    end.

app_check_export_all([]) ->
    ok;
app_check_export_all([Mod|Mods]) ->
    case catch apply(Mod, module_info, [compile]) of
	{'EXIT', {undef,_}} ->
	    app_check_export_all(Mods);
	COpts ->
	    case lists:keysearch(options, 1, COpts) of
		false ->
		    app_check_export_all(Mods);
		{value, {options, List}} ->
		    case lists:member(export_all, List) of
			true ->
			    put(export_all_mods, [Mod|get(export_all_mods)]),
			    app_check_export_all(Mods);
			false ->
			    app_check_export_all(Mods)
		    end
	    end
    end.

%% Given two sorted lists, L1 and L2, returns {NotInL2, NotInL1},
%% NotInL2 is the elements of L1 which don't occurr in L2,
%% NotInL1 is the elements of L2 which don't ocurr in L1.

common(L1, L2) ->
    common(L1, L2, [], []).

common([X|Rest1], [X|Rest2], A1, A2) ->
    common(Rest1, Rest2, A1, A2);
common([X|Rest1], [Y|Rest2], A1, A2) when X < Y ->
    common(Rest1, [Y|Rest2], [X|A1], A2);
common([X|Rest1], [Y|Rest2], A1, A2) ->
    common([X|Rest1], Rest2, A1, [Y|A2]);
common([], L, A1, A2) ->
    {A1, L++A2};
common(L, [], A1, A2) ->
    {L++A1, A2}.

check_apps([]) ->
    ok;
check_apps([App|Apps]) ->
    case is_app(App) of
	{ok, _AppFile} ->
	    ok;
	{error, _} ->
	    put(missing_apps, [App|get(missing_apps)])
    end,
    check_apps(Apps).

check_fields([], _AppFile) ->
    ok;
check_fields([L|Ls], AppFile) ->
    check_field(L, AppFile),
    check_fields(Ls, AppFile).

check_field(FieldName, AppFile) ->
    case lists:keymember(FieldName, 1, AppFile) of
	true ->
	    ok;
	false ->
	    put(missing_fields, [FieldName|get(missing_fields)]),
	    ok
    end.

check_dict(Dict, Reason) ->
    case get(Dict) of
	[] ->
	    1;                         % All ok.
	List ->
	    io:format("** ~s (~s) ->~n~p~n",[Reason, Dict, List]),
	    0
    end.

check_dict_tolerant(Dict, Reason, Mode) ->
    case get(Dict) of
	[] ->
	    1;                         % All ok.
	List ->
	    io:format("** ~s (~s) ->~n~p~n",[Reason, Dict, List]),
	    case Mode of
		pedantic ->
		    0;
		_ ->
		    1
	    end
    end.

get_ebin_modnames(AppName) ->
    Wc=filename:join([code:lib_dir(AppName),"ebin",
		      "*"++code:objfile_extension()]),
    TheFun=fun(X, Acc) ->
		   [list_to_atom(filename:rootname(
				   filename:basename(X)))|Acc] end,
    _Files=lists:foldl(TheFun, [], filelib:wildcard(Wc)).

%%
%% This function removes any erl_crash_dump* files found in the
%% test server directory. Done only once when the test server
%% is started.
%%
cleanup_crash_dumps() ->
    Dir = crash_dump_dir(),
    Dumps = filelib:wildcard(filename:join(Dir, "erl_crash_dump*")),
    delete_files(Dumps).

crash_dump_dir() ->
    filename:dirname(code:which(?MODULE)).

tar_crash_dumps() ->
    Dir = crash_dump_dir(),
    case filelib:wildcard(filename:join(Dir, "erl_crash_dump*")) of
	[] -> {error,no_crash_dumps};
	Dumps ->
	    TarFileName = filename:join(Dir,?crash_dump_tar),
	    {ok,Tar} = erl_tar:open(TarFileName,[write,compressed]),
	    lists:foreach(
	      fun(File) -> 
		      ok = erl_tar:add(Tar,File,filename:basename(File),[])
	      end,
	      Dumps),
	    ok = erl_tar:close(Tar),
	    delete_files(Dumps),
	    {ok,TarFileName}
    end.


check_new_crash_dumps() ->
    Dir = crash_dump_dir(),
    Dumps = filelib:wildcard(filename:join(Dir, "erl_crash_dump*")),
    case length(Dumps) of
	0 ->
	    ok;
	Num ->
	    test_server_ctrl:format(minor,
				    "Found ~p crash dumps:~n", [Num]),
	    append_files_to_logfile(Dumps),
	    delete_files(Dumps)
    end.

append_files_to_logfile([]) -> ok;
append_files_to_logfile([File|Files]) ->
    NodeName=from($., File),
    test_server_ctrl:format(minor, "Crash dump from node ~p:~n",[NodeName]),
    Fd=get(test_server_minor_fd),
    case file:read_file(File) of
	{ok, Bin} ->
	    case file:write(Fd, Bin) of
		ok ->
		    ok;
		{error,Error} ->
		    %% Write failed. The following io:format/3 will probably also
		    %% fail, but in that case it will throw an exception so that
		    %% we will be aware of the problem.
		    io:format(Fd, "Unable to write the crash dump "
			      "to this file: ~p~n", [file:format_error(Error)])
	    end;
	_Error ->
	    io:format(Fd, "Failed to read: ~s\n", [File])
    end,
    append_files_to_logfile(Files).

delete_files([]) -> ok;
delete_files([File|Files]) ->
    io:format("Deleting file: ~s~n", [File]),
    case file:delete(File) of
	{error, _} ->
	    case file:rename(File, File++".old") of
		{error, Error} ->
		    io:format("Could neither delete nor rename file "
			      "~s: ~s.~n", [File, Error]);
		_ ->
		    ok
	    end;
	_ ->
	    ok
    end,
    delete_files(Files).


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% erase_dictionary(Vars) -> ok
%% Vars = [atom(),...]
%%
%% Takes a list of dictionary keys, KeyVals, erases
%% each key and returns ok.
erase_dictionary([{Var, _Val}|Vars]) ->
    erase(Var),
    erase_dictionary(Vars);
erase_dictionary([]) ->
    ok.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% fill_dictionary(KeyVals) -> void()
%% KeyVals = [{atom(),term()},...]
%%
%% Takes each Key-Value pair, and inserts it in the process dictionary.
fill_dictionary([{Var,Val}|Vars]) ->
    put(Var,Val),
    fill_dictionary(Vars);
fill_dictionary([]) ->
    [].



%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% get_username() -> UserName
%%
%% Returns the current user
get_username() ->
    getenv_any(["USER","USERNAME"]).
    
getenv_any([Key|Rest]) ->
    case catch os:getenv(Key) of
	String when is_list(String) -> String;
	false -> getenv_any(Rest)
    end;
getenv_any([]) -> "".


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% get_os_family() -> OsFamily
%%
%% Returns the OS family
get_os_family() ->
    case os:type() of
	{OsFamily,_OsName} -> OsFamily;
	OsFamily -> OsFamily
    end.


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% hostatom()/hostatom(Node) -> Host; atom()
%% hoststr() | hoststr(Node) -> Host; string()
%%
%% Returns the OS family
hostatom() ->
    hostatom(node()).
hostatom(Node) ->
    list_to_atom(hoststr(Node)).
hoststr() ->
    hoststr(node()).
hoststr(Node) when is_atom(Node) ->
    hoststr(atom_to_list(Node));
hoststr(Node) when is_list(Node) ->
    from($@, Node).
    
from(H, [H | T]) -> T;
from(H, [_ | T]) -> from(H, T);
from(_H, []) -> [].


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% framework_call(Callback,Func,Args,DefaultReturn) -> Return | DefaultReturn
%% 
%% Calls the given Func in Callback
framework_call(Func,Args) ->
    framework_call(Func,Args,ok).
framework_call(Func,Args,DefaultReturn) ->
    CB = os:getenv("TEST_SERVER_FRAMEWORK"),
    framework_call(CB,Func,Args,DefaultReturn).
framework_call(FW,_Func,_Args,DefaultReturn)  
  when FW =:= false; FW =:= "undefined" ->
    DefaultReturn;
framework_call(Callback,Func,Args,DefaultReturn) ->
    Mod = list_to_atom(Callback),
    case code:is_loaded(Mod) of
	false -> code:load_file(Mod);
	_ -> ok
    end,
    case erlang:function_exported(Mod,Func,length(Args)) of
	true ->
	    put(test_server_loc, {Mod,Func,framework}),
	    EH = fun(Reason) -> exit({fw_error,{Mod,Func,Reason}}) end,
	    try apply(Mod,Func,Args) of
		Result ->
		    Result
	    catch
		exit:Why ->
		    EH(Why);
		error:Why ->
		    EH({Why,erlang:get_stacktrace()});
		throw:Why ->
		    EH(Why)
	    end;
	false ->
	    DefaultReturn
    end.


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% format_loc(Loc) -> string()
%% 
%% Formats the printout of the line of code read from 
%% process dictionary (test_server_loc). Adds link to 
%% correct line in source code.
format_loc([{Mod,Func,Line}]) ->
    [format_loc1({Mod,Func,Line})];
format_loc([{Mod,Func,Line}|Rest]) ->
    ["[",format_loc1({Mod,Func,Line}),",\n"|format_loc1(Rest)];
format_loc([{Mod,LineOrFunc}]) ->
    format_loc({Mod,LineOrFunc});
format_loc({Mod,Func}) when is_atom(Func) -> 
    io_lib:format("{~s,~w}",[package_str(Mod),Func]);
format_loc({Mod,Line}) when is_integer(Line) -> 
    %% ?line macro is used
    ModStr = package_str(Mod),
    case lists:reverse(ModStr) of
	[$E,$T,$I,$U,$S,$_|_]  ->
	    io_lib:format("{~s,<a href=\"~s~s#~w\">~w</a>}",
			  [ModStr,downcase(ModStr),?src_listing_ext,
			   round_to_10(Line),Line]);
	_ ->
	    io_lib:format("{~s,~w}",[ModStr,Line])
    end;
format_loc(Loc) ->
    io_lib:format("~p",[Loc]).    

format_loc1([{Mod,Func,Line}]) ->
    ["              ",format_loc1({Mod,Func,Line}),"]"];
format_loc1([{Mod,Func,Line}|Rest]) ->
    ["              ",format_loc1({Mod,Func,Line}),",\n"|format_loc1(Rest)];
format_loc1({Mod,Func,Line}) ->
    ModStr = package_str(Mod),
    case lists:reverse(ModStr) of
	[$E,$T,$I,$U,$S,$_|_]  ->
	    io_lib:format("{~s,~w,<a href=\"~s~s#~w\">~w</a>}",
			  [ModStr,Func,downcase(ModStr),?src_listing_ext,
			   round_to_10(Line),Line]);
	_ ->
	    io_lib:format("{~s,~w,~w}",[ModStr,Func,Line])
    end.

round_to_10(N) when (N rem 10) == 0 ->
    N;
round_to_10(N) ->
    trunc(N/10)*10.

downcase(S) -> downcase(S, []).
downcase([Uc|Rest], Result) when $A =< Uc, Uc =< $Z ->
    downcase(Rest, [Uc-$A+$a|Result]);
downcase([C|Rest], Result) ->
    downcase(Rest, [C|Result]);
downcase([], Result) ->
    lists:reverse(Result).

package_str(Mod) when is_atom(Mod) ->
    atom_to_list(Mod);
package_str(Mod) when is_list(Mod), is_atom(hd(Mod)) ->
    %% convert [s1,s2] -> "s1.s2"
    [_|M] = lists:flatten(["."++atom_to_list(S) || S <- Mod]),
    M;
package_str(Mod) when is_list(Mod) ->
    Mod.

package_atom(Mod) when is_atom(Mod) ->
    Mod;
package_atom(Mod) when is_list(Mod), is_atom(hd(Mod)) ->
    list_to_atom(package_str(Mod));
package_atom(Mod) when is_list(Mod) ->
    list_to_atom(Mod).

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% call_trace(TraceSpecFile) -> ok
%%
%% Read terms on format {m,Mod} | {f,Mod,Func}
%% from TraceSpecFile and enable call trace for
%% specified functions.
call_trace(TraceSpec) ->
    case catch try_call_trace(TraceSpec) of
	{'EXIT',Reason} ->
	    erlang:display(Reason),
	    exit(Reason);
	Ok ->
	    Ok
    end.    

try_call_trace(TraceSpec) ->
    case file:consult(TraceSpec) of
	{ok,Terms} ->
	    dbg:tracer(),
	    %% dbg:p(self(), [p, m, sos, call]),
	    dbg:p(self(), [sos, call]),
	    lists:foreach(fun({m,M}) ->
				  case dbg:tpl(M,[{'_',[],[{return_trace}]}]) of
				      {error,What} -> exit({error,{tracing_failed,What}});
				      _ -> ok
				  end;			  
			     ({f,M,F}) ->
				  case dbg:tpl(M,F,[{'_',[],[{return_trace}]}]) of
				      {error,What} -> exit({error,{tracing_failed,What}});
				      _ -> ok
				  end;			  
			     (Huh) ->
				  exit({error,{unrecognized_trace_term,Huh}})
			  end, Terms),
	    ok;
	{_,Error} ->
	    exit({error,{tracing_failed,TraceSpec,Error}})
    end.