Merge branch 'bmk/inets/inets59_integration2' into maint

9 files changed, 465 insertions, 301 deletions

diff --git a/lib/inets/src/inets_app/Makefile b/lib/inets/src/inets_app/Makefile
index d99e33b4ea..6da6a1d79f 100644
--- a/lib/inets/src/inets_app/Makefile
+++ b/lib/inets/src/inets_app/Makefile
@@ -46,7 +46,8 @@ MODULES = \
 	inets_service \
 	inets_app \
 	inets_sup \
-	inets_regexp
+	inets_regexp \
+	inets_trace
 
 INTERNAL_HRL_FILES = inets_internal.hrl
 EXTERNAL_HRL_FILES = ../../include/httpd.hrl \
diff --git a/lib/inets/src/inets_app/inets.app.src b/lib/inets/src/inets_app/inets.app.src
index 1db7ed2c30..4aea2ef3d7 100644
--- a/lib/inets/src/inets_app/inets.app.src
+++ b/lib/inets/src/inets_app/inets.app.src
@@ -18,14 +18,15 @@
 %% 
 
 {application,inets,
- [{description,"INETS  CXC 138 49"},
-  {vsn,"%VSN%"},
+ [{description, "INETS  CXC 138 49"},
+  {vsn, "%VSN%"},
   {modules,[
             inets,
             inets_sup,
             inets_app,
 	    inets_service,	                  
 	    inets_regexp,	                  
+	    inets_trace,	                  
 
             %% FTP
             ftp,
diff --git a/lib/inets/src/inets_app/inets.appup.src b/lib/inets/src/inets_app/inets.appup.src
index e80cb2a23b..c7029f7b31 100644
--- a/lib/inets/src/inets_app/inets.appup.src
+++ b/lib/inets/src/inets_app/inets.appup.src
@@ -18,65 +18,115 @@
 
 {"%VSN%",
  [
+  {"5.8.1", 
+   [
+    {load_module, http_uri,      soft_purge, soft_purge, []}, 
+    {load_module, httpc_response, soft_purge, soft_purge, [http_uri]}, 
+
+    {load_module, httpc,         soft_purge, soft_purge, 
+     [http_uri, httpc_manager]}, 
+    {update,      httpc_manager, soft, soft_purge, soft_purge, [http_uri]},
+
+    {load_module, inets_app, soft_purge, soft_purge, [inets_sup]}, 
+    {update,      inets_sup,     soft, soft_purge, soft_purge, []},
+
+    {load_module, httpd_conf, soft_purge, soft_purge, []}, 
+    {load_module, httpd_response, soft_purge, soft_purge, []}, 
+    {load_module, httpd_script_env, soft_purge, soft_purge, []}, 
+
+    {load_module, inets,         soft_purge, soft_purge, [inets_trace]},
+    {update,      httpc_handler, soft, soft_purge, soft_purge, []},
+    {update,      httpd_sup,     soft, soft_purge, soft_purge, []},
+    {add_module,  inets_trace}
+   ]
+  }, 
   {"5.8",
    [
+    {load_module, http_uri,      soft_purge, soft_purge, []}, 
+    {load_module, httpc_response, soft_purge, soft_purge, [http_uri]}, 
+
+    {load_module, httpc, soft_purge, soft_purge, 
+     [http_uri, httpc_manager]}, 
+
+    {load_module, inets_app, soft_purge, soft_purge, [inets_sup]}, 
+    {update,      inets_sup,     soft, soft_purge, soft_purge, []},
+
+    {load_module, inets, soft_purge, soft_purge, [inets_trace]},
+
+    {load_module, httpd_conf, soft_purge, soft_purge, []}, 
+    {load_module, httpd_response, soft_purge, soft_purge, []}, 
+    {load_module, httpd_script_env, soft_purge, soft_purge, []}, 
+
     {load_module, ftp, soft_purge, soft_purge, []}, 
     {update, httpc_handler, {advanced, upgrade_from_pre_5_8_1}, 
      soft_purge, soft_purge, []}, 
     {update, httpc_manager, {advanced, upgrade_from_pre_5_8_1}, 
-     soft_purge, soft_purge, [httpc_handler]}
+     soft_purge, soft_purge, [http_uri, httpc_handler]},
+    {update,      httpd_sup, soft, soft_purge, soft_purge, []},
+
+    {add_module,  inets_trace}
    ]
   }, 
   {"5.7.2", 
    [
     {restart_application, inets}
    ]
-  }, 
-  {"5.7.1", 
-   [
-    {restart_application, inets}
-   ]
-  }, 
-  {"5.7", 
+  }
+ ],
+ [
+  {"5.8.1",
    [
-    {restart_application, inets}
+    {load_module, http_uri,      soft_purge, soft_purge, []}, 
+    {load_module, httpc_response, soft_purge, soft_purge, [http_uri]}, 
+
+    {load_module, httpc,         soft_purge, soft_purge, 
+     [http_uri, httpc_manager]}, 
+    {update,      httpc_manager, soft, soft_purge, soft_purge, [http_uri]},
+
+    {load_module, inets_app, soft_purge, soft_purge, [inets_sup]}, 
+    {update,      inets_sup,     soft, soft_purge, soft_purge, []},
+
+    {load_module, httpd_conf, soft_purge, soft_purge, []}, 
+    {load_module, httpd_response, soft_purge, soft_purge, []}, 
+    {load_module, httpd_script_env, soft_purge, soft_purge, []}, 
+
+    {load_module, inets,         soft_purge, soft_purge, []},
+    {update,      httpc_handler, soft, soft_purge, soft_purge, []},
+    {update,      httpd_sup,     soft, soft_purge, soft_purge, []},
+    {remove,      {inets_trace, soft_purge, brutal_purge}}
    ]
   }, 
-  {"5.6", 
-   [
-    {restart_application, inets}
-   ]
-  } 
- ],
- [
   {"5.8",
    [
+    {load_module, http_uri,      soft_purge, soft_purge, []}, 
+    {load_module, httpc_response, soft_purge, soft_purge, [http_uri]}, 
+
+    {load_module, httpc,         soft_purge, soft_purge, 
+     [http_uri, httpc_manager]}, 
+
+    {load_module, inets_app, soft_purge, soft_purge, [inets_sup]}, 
+    {update,      inets_sup,     soft, soft_purge, soft_purge, []},
+
+    {load_module, inets, soft_purge, soft_purge, []},
+
+    {load_module, httpd_conf, soft_purge, soft_purge, []}, 
+    {load_module, httpd_response, soft_purge, soft_purge, []}, 
+    {load_module, httpd_script_env, soft_purge, soft_purge, []}, 
+
     {load_module, ftp, soft_purge, soft_purge, []}, 
     {update, httpc_handler, {advanced, upgrade_from_pre_5_8_1}, 
      soft_purge, soft_purge, []}, 
     {update, httpc_manager, {advanced, upgrade_from_pre_5_8_1}, 
-     soft_purge, soft_purge, [httpc_handler]}
+     soft_purge, soft_purge, [http_uri, httpc_handler]},
+    {update,      httpd_sup, soft, soft_purge, soft_purge, []},
+
+    {remove,      {inets_trace, soft_purge, brutal_purge}}
    ]
   }, 
   {"5.7.2", 
    [
     {restart_application, inets}
    ]
-  }, 
-  {"5.7.1", 
-   [
-    {restart_application, inets}
-   ]
-  }, 
-  {"5.7", 
-   [
-    {restart_application, inets}
-   ]
-  }, 
-  {"5.6", 
-   [
-    {restart_application, inets}
-   ]
   } 
  ]
 }.
diff --git a/lib/inets/src/inets_app/inets.erl b/lib/inets/src/inets_app/inets.erl
index 054468e445..8e79f8d456 100644
--- a/lib/inets/src/inets_app/inets.erl
+++ b/lib/inets/src/inets_app/inets.erl
@@ -28,7 +28,7 @@
 	 stop/0, stop/2, 
 	 services/0, services_info/0,
 	 service_names/0]).
--export([enable_trace/2, enable_trace/3, disable_trace/0, set_trace/1, 
+-export([enable_trace/2, enable_trace/3, disable_trace/0, set_trace/1,
 	 report_event/4]).
 -export([versions/0,
          print_version_info/0, print_version_info/1]).
@@ -409,47 +409,8 @@ service_names() ->
 %% Severity withing Limit) will be written to stdout using io:format.
 %%
 %%-----------------------------------------------------------------
-enable_trace(Level, Dest) ->
-    enable_trace(Level, Dest, all).
-
-enable_trace(Level, Dest, Service) ->
-    case valid_trace_service(Service) of
-	true ->
-	    enable_trace2(Level, Dest, Service);
-	false ->
-	    {error, {invalid_service, Service}}
-    end.
-
-enable_trace2(Level, File, Service) 
-  when is_list(File) ->
-    case file:open(File, [write]) of
-	{ok, Fd} ->
-	    HandleSpec = {fun handle_trace/2, {Service, Fd}},
-	    do_enable_trace(Level, process, HandleSpec);
-	Err ->
-	    Err
-    end;
-enable_trace2(Level, Port, _) when is_integer(Port) ->
-    do_enable_trace(Level, port, dbg:trace_port(ip, Port));
-enable_trace2(Level, io, Service) ->
-    HandleSpec = {fun handle_trace/2, {Service, standard_io}},
-    do_enable_trace(Level, process, HandleSpec);
-enable_trace2(Level, {Fun, _Data} = HandleSpec, _) when is_function(Fun) ->
-    do_enable_trace(Level, process, HandleSpec).
-
-do_enable_trace(Level, Type, HandleSpec) ->
-    case dbg:tracer(Type, HandleSpec) of
-	{ok, _} ->
-	    set_trace(Level),
-	    ok;
-	Error ->
-	    Error
-    end.    
-
-valid_trace_service(all) ->
-    true;
-valid_trace_service(Service) ->
-    lists:member(Service, [httpc, httpd, ftpc, tftp]).
+enable_trace(Level, Dest)          -> inets_trace:enable(Level, Dest).
+enable_trace(Level, Dest, Service) -> inets_trace:enable(Level, Dest, Service).
 
 
 %%-----------------------------------------------------------------
@@ -458,12 +419,7 @@ valid_trace_service(Service) ->
 %% Description:
 %% This function is used to stop tracing.
 %%-----------------------------------------------------------------
-disable_trace() ->
-    %% This is to make handle_trace/2 close the output file (if the
-    %% event gets there before dbg closes)
-    inets:report_event(100, "stop trace", stop_trace, [stop_trace]),  
-    dbg:stop().
-
+disable_trace() -> inets_trace:disable().
 
 
 %%-----------------------------------------------------------------
@@ -476,60 +432,7 @@ disable_trace() ->
 %% This function is used to change the trace level when tracing has
 %% already been started.
 %%-----------------------------------------------------------------
-set_trace(Level) ->
-    set_trace(Level, all).
-
-set_trace(Level, Service) ->
-    Pat = make_pattern(?MODULE, Service, Level),
-    change_pattern(Pat).
-
-make_pattern(Mod, Service, Level) 
-  when is_atom(Mod) andalso is_atom(Service) ->
-    case Level of
-        min ->
-            {Mod, Service, []};
-        max ->
-            Head = ['$1', '_', '_', '_'],
-            Body = [],
-            Cond = [],
-            {Mod, Service, [{Head, Cond, Body}]};
-        DetailLevel when is_integer(DetailLevel) ->
-            Head = ['$1', '_', '_', '_'],
-            Body = [],
-            Cond = [{ '=<', '$1', DetailLevel}],
-            {Mod, Service, [{Head, Cond, Body}]};
-        _ ->
-            exit({bad_level, Level})
-    end.
-
-change_pattern({Mod, Service, Pattern}) 
-  when is_atom(Mod) andalso is_atom(Service) ->
-    MFA = {Mod, report_event, 4},
-    case Pattern of
-        [] ->
-	    try
-		error_to_exit(ctp, dbg:ctp(MFA)),
-		error_to_exit(p,   dbg:p(all, clear))
-	    catch
-		exit:{Where, Reason} ->
-		    {error, {Where, Reason}}
-	    end;
-        List when is_list(List) ->
-	    try
-		error_to_exit(ctp, dbg:ctp(MFA)),
-		error_to_exit(tp,  dbg:tp(MFA, Pattern)),
-		error_to_exit(p,   dbg:p(all, [call, timestamp]))
-	    catch
-		exit:{Where, Reason} ->
-		    {error, {Where, Reason}}
-	    end
-    end,
-    ok.
-
-error_to_exit(_Where, {ok, _} = OK) ->
-    OK;
-error_to_exit(Where, {error, Reason}) ->
-    exit({Where, Reason}).
+set_trace(Level) -> inets_trace:set_level(Level).
 
 
 %%-----------------------------------------------------------------
@@ -546,164 +449,8 @@ error_to_exit(Where, {error, Reason}) ->
 %% put trace on this function.
 %%-----------------------------------------------------------------
 
-report_event(Severity, Label, Service, Content) 
-  when (is_integer(Severity) andalso 
-	(Severity >= 0) andalso (100 >= Severity)) andalso 
-       is_list(Label) andalso 
-       is_atom(Service) andalso 
-       is_list(Content) ->
-    hopefully_traced.
-
-
-%% ----------------------------------------------------------------------
-%% handle_trace(Event, Fd) -> Verbosity
-%%
-%% Parameters:
-%% Event -> The trace event (only megaco 'trace_ts' events are printed)
-%% Fd -> standard_io | file_descriptor() | trace_port()
-%%
-%% Description:
-%% This function is used to "receive" and print the trace events.
-%% Events are printed if:
-%%   - Verbosity is max
-%%   - Severity is =< Verbosity (e.g. Severity = 30, and Verbosity = 40)
-%% Events are not printed if:
-%%   - Verbosity is min
-%%   - Severity is > Verbosity
-%%-----------------------------------------------------------------
-
-handle_trace(_, closed_file = Fd) ->
-    Fd;
-handle_trace({trace_ts, _Who, call,
-              {?MODULE, report_event,
-               [_Sev, "stop trace", stop_trace, [stop_trace]]},
-              Timestamp},
-             {_, standard_io} = Fd) ->
-    (catch io:format(standard_io, "stop trace at ~s~n", [format_timestamp(Timestamp)])),
-    Fd;
-handle_trace({trace_ts, _Who, call,
-              {?MODULE, report_event,
-               [_Sev, "stop trace", stop_trace, [stop_trace]]},
-              Timestamp},
-             standard_io = Fd) ->
-    (catch io:format(Fd, "stop trace at ~s~n", [format_timestamp(Timestamp)])),
-    Fd;
-handle_trace({trace_ts, _Who, call,
-              {?MODULE, report_event,
-               [_Sev, "stop trace", stop_trace, [stop_trace]]},
-              Timestamp},
-             {_Service, Fd}) ->
-    (catch io:format(Fd, "stop trace at ~s~n", [format_timestamp(Timestamp)])),
-    (catch file:close(Fd)),
-    closed_file;
-handle_trace({trace_ts, _Who, call,
-              {?MODULE, report_event,
-               [_Sev, "stop trace", stop_trace, [stop_trace]]},
-              Timestamp},
-             Fd) ->
-    (catch io:format(Fd, "stop trace at ~s~n", [format_timestamp(Timestamp)])),
-    (catch file:close(Fd)),
-    closed_file;
-handle_trace({trace_ts, Who, call,
-              {?MODULE, report_event,
-               [Sev, Label, Service, Content]}, Timestamp},
-             Fd) ->
-    (catch print_inets_trace(Fd, Sev, Timestamp, Who, 
-			     Label, Service, Content)),
-    Fd;
-handle_trace(Event, Fd) ->
-    (catch print_trace(Fd, Event)),
-    Fd.
-
-
-print_inets_trace({Service, Fd}, 
-		  Sev, Timestamp, Who, Label, Service, Content) ->
-    do_print_inets_trace(Fd, Sev, Timestamp, Who, Label, Service, Content);
-print_inets_trace({ServiceA, Fd}, 
-		  Sev, Timestamp, Who, Label, ServiceB, Content) 
-  when (ServiceA =:= all) ->
-    do_print_inets_trace(Fd, Sev, Timestamp, Who, Label, ServiceB, Content);
-print_inets_trace({ServiceA, _Fd}, 
-		  _Sev, _Timestamp, _Who, _Label, ServiceB, _Content) 
-  when ServiceA =/= ServiceB ->
-    ok;
-print_inets_trace(Fd, Sev, Timestamp, Who, Label, Service, Content) ->
-    do_print_inets_trace(Fd, Sev, Timestamp, Who, Label, Service, Content).
-
-do_print_inets_trace(Fd, Sev, Timestamp, Who, Label, Service, Content) ->
-    Ts = format_timestamp(Timestamp),
-    io:format(Fd, "[inets ~w trace ~w ~w ~s] ~s "
-              "~n   Content: ~p"
-              "~n",
-              [Service, Sev, Who, Ts, Label, Content]).
-
-print_trace({_, Fd}, Event) ->
-    do_print_trace(Fd, Event);
-print_trace(Fd, Event) ->
-    do_print_trace(Fd, Event).
-
-do_print_trace(Fd, {trace, Who, What, Where}) ->
-    io:format(Fd, "[trace]"
-              "~n   Who:   ~p"
-              "~n   What:  ~p"
-              "~n   Where: ~p"
-              "~n", [Who, What, Where]);
-
-do_print_trace(Fd, {trace, Who, What, Where, Extra}) ->
-    io:format(Fd, "[trace]"
-              "~n   Who:   ~p"
-              "~n   What:  ~p"
-              "~n   Where: ~p"
-              "~n   Extra: ~p"
-              "~n", [Who, What, Where, Extra]);
-
-do_print_trace(Fd, {trace_ts, Who, What, Where, When}) ->
-    Ts = format_timestamp(When),
-    io:format(Fd, "[trace ~s]"
-              "~n   Who:   ~p"
-              "~n   What:  ~p"
-              "~n   Where: ~p"
-              "~n", [Ts, Who, What, Where]);
-
-do_print_trace(Fd, {trace_ts, Who, What, Where, Extra, When}) ->
-    Ts = format_timestamp(When),
-    io:format(Fd, "[trace ~s]"
-              "~n   Who:   ~p"
-              "~n   What:  ~p"
-              "~n   Where: ~p"
-              "~n   Extra: ~p"
-              "~n", [Ts, Who, What, Where, Extra]);
-
-do_print_trace(Fd, {seq_trace, What, Where}) ->
-    io:format(Fd, "[seq trace]"
-              "~n   What:       ~p"
-              "~n   Where:      ~p"
-              "~n", [What, Where]);
-
-do_print_trace(Fd, {seq_trace, What, Where, When}) ->
-    Ts = format_timestamp(When),
-    io:format(Fd, "[seq trace ~s]"
-              "~n   What:       ~p"
-              "~n   Where:      ~p"
-              "~n", [Ts, What, Where]);
-
-do_print_trace(Fd, {drop, Num}) ->
-    io:format(Fd, "[drop trace] ~p~n", [Num]);
-
-do_print_trace(Fd, Trace) ->
-    io:format(Fd, "[trace] "
-              "~n   ~p"
-              "~n", [Trace]).
-
-
-format_timestamp({_N1, _N2, N3} = Now) ->
-    {Date, Time}   = calendar:now_to_datetime(Now),
-    {YYYY,MM,DD}   = Date,
-    {Hour,Min,Sec} = Time,
-    FormatDate =
-        io_lib:format("~.4w:~.2.0w:~.2.0w ~.2.0w:~.2.0w:~.2.0w 4~w",
-                      [YYYY,MM,DD,Hour,Min,Sec,round(N3/1000)]),
-    lists:flatten(FormatDate).
+report_event(Severity, Label, Service, Content) ->
+    inets_trace:report_event(Severity, Label, Service, Content).
 
 
 %%--------------------------------------------------------------------
diff --git a/lib/inets/src/inets_app/inets.mk b/lib/inets/src/inets_app/inets.mk
index 194b4ca2b1..d24cc0aea3 100644
--- a/lib/inets/src/inets_app/inets.mk
+++ b/lib/inets/src/inets_app/inets.mk
@@ -41,8 +41,6 @@ INETS_APP_VSN_COMPILE_FLAGS = \
 	+'{parse_transform,sys_pre_attributes}' \
 	+'{attribute,insert,app_vsn,$(APP_VSN)}'
 
-INETS_FLAGS = -D'SERVER_SOFTWARE="$(APPLICATION)/$(VSN)"'
-
 INETS_ERL_COMPILE_FLAGS += \
 	-pa $(ERL_TOP)/lib/inets/ebin  \
 	$(INETS_APP_VSN_COMPILE_FLAGS) 
diff --git a/lib/inets/src/inets_app/inets_app.erl b/lib/inets/src/inets_app/inets_app.erl
index cae79a6767..77c39d85eb 100644
--- a/lib/inets/src/inets_app/inets_app.erl
+++ b/lib/inets/src/inets_app/inets_app.erl
@@ -24,7 +24,7 @@
 -export([start/2, stop/1]).
 
 start(_Type, _State) ->
-    supervisor:start_link({local, inets_sup}, inets_sup, []).
+    inets_sup:start_link().
 
 stop(_State) ->
     ok.
diff --git a/lib/inets/src/inets_app/inets_internal.hrl b/lib/inets/src/inets_app/inets_internal.hrl
index 55c3669e4a..e56af3b59d 100644
--- a/lib/inets/src/inets_app/inets_internal.hrl
+++ b/lib/inets/src/inets_app/inets_internal.hrl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %% 
-%% Copyright Ericsson AB 2005-2009. All Rights Reserved.
+%% Copyright Ericsson AB 2005-2011. 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
@@ -24,8 +24,8 @@
 %% Various trace macros
 
 -define(report(Severity, Label, Service, Content), 
-	inets:report_event(Severity, Label, Service, 
-			   [{module, ?MODULE}, {line, ?LINE} | Content])).
+	inets_trace:report_event(Severity, Label, Service, 
+				 [{module, ?MODULE}, {line, ?LINE} | Content])).
 -define(report_important(Label, Service, Content), 
 	?report(20, Label, Service, Content)).
 -define(report_verbose(Label, Service, Content),   
diff --git a/lib/inets/src/inets_app/inets_sup.erl b/lib/inets/src/inets_app/inets_sup.erl
index 20d5ef343e..0382362778 100644
--- a/lib/inets/src/inets_app/inets_sup.erl
+++ b/lib/inets/src/inets_app/inets_sup.erl
@@ -25,9 +25,19 @@
 
 -behaviour(supervisor).
 
+%% External API
+-export([start_link/0]).
+
+%% Supervisor callbacks
 -export([init/1]).
 
 %%%=========================================================================
+%%%  External functions
+%%%=========================================================================
+start_link() ->
+    supervisor:start_link({local, ?MODULE}, ?MODULE, []).
+
+%%%=========================================================================
 %%%  Supervisor callback
 %%%=========================================================================
 init([]) ->
diff --git a/lib/inets/src/inets_app/inets_trace.erl b/lib/inets/src/inets_app/inets_trace.erl
new file mode 100644
index 0000000000..8911f65897
--- /dev/null
+++ b/lib/inets/src/inets_app/inets_trace.erl
@@ -0,0 +1,357 @@
+%%
+%% %CopyrightBegin%
+%% 
+%% Copyright Ericsson AB 2011-2012. 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
+%% 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: Module for debug trace functions of the inets application
+%%----------------------------------------------------------------------
+
+-module(inets_trace).
+
+%% API
+-export([enable/2, enable/3, 
+	 disable/0, 
+	 set_level/1, set_level/2, 
+	 report_event/4]).
+
+
+%%====================================================================
+%% API
+%%====================================================================
+
+%%-----------------------------------------------------------------
+%% enable(Level, Destination) -> void()
+%% enable(Level, Destination, Service) -> void()
+%%
+%% Parameters:
+%% Level -> max | min | integer()
+%% Destination -> File | Port | io | HandlerSpec
+%% Service -> httpc | httpd | ftpc | tftp | all
+%% File -> string()
+%% Port -> integer()
+%% Verbosity -> true | false
+%% HandlerSpec = {function(), Data}
+%% Data = term()
+%%
+%% Description:
+%% This function is used to start tracing at level Level and send
+%% the result either to the file File, the port Port or to a 
+%% trace handler. 
+%% Note that it starts a tracer server.
+%% When Destination is the atom io (or the tuple {io, Verbosity}),
+%% all (printable) inets trace events (trace_ts events which has
+%% Severity withing Limit) will be written to stdout using io:format.
+%%
+%%-----------------------------------------------------------------
+enable(Level, Dest) ->
+    enable(Level, Dest, all).
+
+enable(Level, Dest, Service) ->
+    case valid_trace_service(Service) of
+	true ->
+	    enable2(Level, Dest, Service);
+	false ->
+	    {error, {invalid_service, Service}}
+    end.
+
+enable2(Level, File, Service) 
+  when is_list(File) ->
+    case file:open(File, [write]) of
+	{ok, Fd} ->
+	    HandleSpec = {fun handle_trace/2, {Service, Fd}},
+	    do_enable(Level, process, HandleSpec);
+	Err ->
+	    Err
+    end;
+enable2(Level, Port, _) when is_integer(Port) ->
+    do_enable(Level, port, dbg:trace_port(ip, Port));
+enable2(Level, io, Service) ->
+    HandleSpec = {fun handle_trace/2, {Service, standard_io}},
+    do_enable(Level, process, HandleSpec);
+enable2(Level, {Fun, _Data} = HandleSpec, _) when is_function(Fun) ->
+    do_enable(Level, process, HandleSpec).
+
+do_enable(Level, Type, HandleSpec) ->
+    case dbg:tracer(Type, HandleSpec) of
+	{ok, _} ->
+	    set_level(Level),
+	    ok;
+	Error ->
+	    Error
+    end.    
+
+valid_trace_service(all) ->
+    true;
+valid_trace_service(Service) ->
+    lists:member(Service, [httpc, httpd, ftpc, tftp]).
+
+
+%%-----------------------------------------------------------------
+%% disable() -> void()
+%%
+%% Description:
+%% This function is used to stop tracing.
+%%-----------------------------------------------------------------
+
+disable() ->
+    %% This is to make handle_trace/2 close the output file (if the
+    %% event gets there before dbg closes)
+    inets_trace:report_event(100, "stop trace", stop_trace, [stop_trace]),  
+    dbg:stop().
+
+
+
+%%-----------------------------------------------------------------
+%% set_level(Level) -> void()
+%%
+%% Parameters:
+%% Level -> max | min | integer()
+%%
+%% Description:
+%% This function is used to change the trace level when tracing has
+%% already been started.
+%%-----------------------------------------------------------------
+set_level(Level) ->
+    set_level(Level, all).
+
+set_level(Level, Service) ->
+    Pat = make_pattern(?MODULE, Service, Level),
+    change_pattern(Pat).
+
+make_pattern(Mod, Service, Level) 
+  when is_atom(Mod) andalso is_atom(Service) ->
+    case Level of
+        min ->
+            {Mod, Service, []};
+        max ->
+            Head = ['$1', '_', '_', '_'],
+            Body = [],
+            Cond = [],
+            {Mod, Service, [{Head, Cond, Body}]};
+        DetailLevel when is_integer(DetailLevel) ->
+            Head = ['$1', '_', '_', '_'],
+            Body = [],
+            Cond = [{ '=<', '$1', DetailLevel}],
+            {Mod, Service, [{Head, Cond, Body}]};
+        _ ->
+            exit({bad_level, Level})
+    end.
+
+change_pattern({Mod, Service, Pattern}) 
+  when is_atom(Mod) andalso is_atom(Service) ->
+    MFA = {Mod, report_event, 4},
+    case Pattern of
+        [] ->
+	    try
+		error_to_exit(ctp, dbg:ctp(MFA)),
+		error_to_exit(p,   dbg:p(all, clear))
+	    catch
+		exit:{Where, Reason} ->
+		    {error, {Where, Reason}}
+	    end;
+        List when is_list(List) ->
+	    try
+		error_to_exit(ctp, dbg:ctp(MFA)),
+		error_to_exit(tp,  dbg:tp(MFA, Pattern)),
+		error_to_exit(p,   dbg:p(all, [call, timestamp]))
+	    catch
+		exit:{Where, Reason} ->
+		    {error, {Where, Reason}}
+	    end
+    end.
+
+error_to_exit(_Where, {ok, _} = OK) ->
+    OK;
+error_to_exit(Where, {error, Reason}) ->
+    exit({Where, Reason}).
+
+
+%%-----------------------------------------------------------------
+%% report_event(Severity, Label, Service, Content)
+%%
+%% Parameters:
+%% Severity -> 0 =< integer() =< 100
+%% Label -> string()
+%% Service -> httpd | httpc | ftp | tftp
+%% Content -> [{tag, term()}]
+%%
+%% Description:
+%% This function is used to generate trace events, that is,  
+%% put trace on this function.
+%%-----------------------------------------------------------------
+
+report_event(Severity, Label, Service, Content) 
+  when (is_integer(Severity) andalso 
+	(Severity >= 0) andalso (100 >= Severity)) andalso 
+       is_list(Label) andalso 
+       is_atom(Service) andalso 
+       is_list(Content) ->
+    hopefully_traced.
+
+
+%% ----------------------------------------------------------------------
+%% handle_trace(Event, Fd) -> Verbosity
+%%
+%% Parameters:
+%% Event -> The trace event
+%% Fd -> standard_io | file_descriptor() | trace_port()
+%%
+%% Description:
+%% This function is used to "receive" and pretty print the trace events.
+%% Events are printed if:
+%%   - Verbosity is max
+%%   - Severity is =< Verbosity (e.g. Severity = 30, and Verbosity = 40)
+%% Events are not printed if:
+%%   - Verbosity is min
+%%   - Severity is > Verbosity
+%%-----------------------------------------------------------------
+
+handle_trace(_, closed_file = Fd) ->
+    Fd;
+handle_trace({trace_ts, _Who, call,
+              {?MODULE, report_event,
+               [_Sev, "stop trace", stop_trace, [stop_trace]]},
+              Timestamp},
+             {_, standard_io} = Fd) ->
+    (catch io:format(standard_io, "stop trace at ~s~n", [format_timestamp(Timestamp)])),
+    Fd;
+handle_trace({trace_ts, _Who, call,
+              {?MODULE, report_event,
+               [_Sev, "stop trace", stop_trace, [stop_trace]]},
+              Timestamp},
+             standard_io = Fd) ->
+    (catch io:format(Fd, "stop trace at ~s~n", [format_timestamp(Timestamp)])),
+    Fd;
+handle_trace({trace_ts, _Who, call,
+              {?MODULE, report_event,
+               [_Sev, "stop trace", stop_trace, [stop_trace]]},
+              Timestamp},
+             {_Service, Fd}) ->
+    (catch io:format(Fd, "stop trace at ~s~n", [format_timestamp(Timestamp)])),
+    (catch file:close(Fd)),
+    closed_file;
+handle_trace({trace_ts, _Who, call,
+              {?MODULE, report_event,
+               [_Sev, "stop trace", stop_trace, [stop_trace]]},
+              Timestamp},
+             Fd) ->
+    (catch io:format(Fd, "stop trace at ~s~n", [format_timestamp(Timestamp)])),
+    (catch file:close(Fd)),
+    closed_file;
+handle_trace({trace_ts, Who, call,
+              {?MODULE, report_event,
+               [Sev, Label, Service, Content]}, Timestamp},
+             Fd) ->
+    (catch print_inets_trace(Fd, Sev, Timestamp, Who, 
+			     Label, Service, Content)),
+    Fd;
+handle_trace(Event, Fd) ->
+    (catch print_trace(Fd, Event)),
+    Fd.
+
+
+print_inets_trace({Service, Fd}, 
+		  Sev, Timestamp, Who, Label, Service, Content) ->
+    do_print_inets_trace(Fd, Sev, Timestamp, Who, Label, Service, Content);
+print_inets_trace({ServiceA, Fd}, 
+		  Sev, Timestamp, Who, Label, ServiceB, Content) 
+  when (ServiceA =:= all) ->
+    do_print_inets_trace(Fd, Sev, Timestamp, Who, Label, ServiceB, Content);
+print_inets_trace({ServiceA, _Fd}, 
+		  _Sev, _Timestamp, _Who, _Label, ServiceB, _Content) 
+  when ServiceA =/= ServiceB ->
+    ok;
+print_inets_trace(Fd, Sev, Timestamp, Who, Label, Service, Content) ->
+    do_print_inets_trace(Fd, Sev, Timestamp, Who, Label, Service, Content).
+
+do_print_inets_trace(Fd, Sev, Timestamp, Who, Label, Service, Content) ->
+    Ts = format_timestamp(Timestamp),
+    io:format(Fd, "[inets ~w trace ~w ~w ~s] ~s "
+              "~n   Content: ~p"
+              "~n",
+              [Service, Sev, Who, Ts, Label, Content]).
+
+print_trace({_, Fd}, Event) ->
+    do_print_trace(Fd, Event);
+print_trace(Fd, Event) ->
+    do_print_trace(Fd, Event).
+
+do_print_trace(Fd, {trace, Who, What, Where}) ->
+    io:format(Fd, "[trace]"
+              "~n   Who:   ~p"
+              "~n   What:  ~p"
+              "~n   Where: ~p"
+              "~n", [Who, What, Where]);
+
+do_print_trace(Fd, {trace, Who, What, Where, Extra}) ->
+    io:format(Fd, "[trace]"
+              "~n   Who:   ~p"
+              "~n   What:  ~p"
+              "~n   Where: ~p"
+              "~n   Extra: ~p"
+              "~n", [Who, What, Where, Extra]);
+
+do_print_trace(Fd, {trace_ts, Who, What, Where, When}) ->
+    Ts = format_timestamp(When),
+    io:format(Fd, "[trace ~s]"
+              "~n   Who:   ~p"
+              "~n   What:  ~p"
+              "~n   Where: ~p"
+              "~n", [Ts, Who, What, Where]);
+
+do_print_trace(Fd, {trace_ts, Who, What, Where, Extra, When}) ->
+    Ts = format_timestamp(When),
+    io:format(Fd, "[trace ~s]"
+              "~n   Who:   ~p"
+              "~n   What:  ~p"
+              "~n   Where: ~p"
+              "~n   Extra: ~p"
+              "~n", [Ts, Who, What, Where, Extra]);
+
+do_print_trace(Fd, {seq_trace, What, Where}) ->
+    io:format(Fd, "[seq trace]"
+              "~n   What:       ~p"
+              "~n   Where:      ~p"
+              "~n", [What, Where]);
+
+do_print_trace(Fd, {seq_trace, What, Where, When}) ->
+    Ts = format_timestamp(When),
+    io:format(Fd, "[seq trace ~s]"
+              "~n   What:       ~p"
+              "~n   Where:      ~p"
+              "~n", [Ts, What, Where]);
+
+do_print_trace(Fd, {drop, Num}) ->
+    io:format(Fd, "[drop trace] ~p~n", [Num]);
+
+do_print_trace(Fd, Trace) ->
+    io:format(Fd, "[trace] "
+              "~n   ~p"
+              "~n", [Trace]).
+
+
+format_timestamp({_N1, _N2, N3} = Now) ->
+    {Date, Time}   = calendar:now_to_datetime(Now),
+    {YYYY,MM,DD}   = Date,
+    {Hour,Min,Sec} = Time,
+    FormatDate =
+        io_lib:format("~.4w:~.2.0w:~.2.0w ~.2.0w:~.2.0w:~.2.0w 4~w",
+                      [YYYY,MM,DD,Hour,Min,Sec,round(N3/1000)]),
+    lists:flatten(FormatDate).
+
+