%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1999-2013. All Rights Reserved.
%%
%% Licensed under the Apache License, Version 2.0 (the "License");
%% you may not use this file except in compliance with the License.
%% You may obtain a copy of the License at
%%
%% http://www.apache.org/licenses/LICENSE-2.0
%%
%% Unless required by applicable law or agreed to in writing, software
%% distributed under the License is distributed on an "AS IS" BASIS,
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%% See the License for the specific language governing permissions and
%% limitations under the License.
%%
%% %CopyrightEnd%
%%
-module(erts_debug).
%% Low-level debugging support. EXPERIMENTAL!
-export([size/1,df/1,df/2,df/3,ic/1]).
%% This module contains the following *experimental* BIFs:
%% disassemble/1
%% breakpoint/2
%% same/2
%% flat_size/1
%%% BIFs
-export([breakpoint/2, disassemble/1, display/1, dist_ext_to_term/2,
dump_monitors/1, dump_links/1, flat_size/1,
get_internal_state/1, instructions/0, lock_counters/1,
map_info/1, same/2, set_internal_state/2,
size_shared/1, copy_shared/1]).
-spec breakpoint(MFA, Flag) -> non_neg_integer() when
MFA :: {Module :: module(),
Function :: atom(),
Arity :: arity() | '_'},
Flag :: boolean().
breakpoint(_, _) ->
erlang:nif_error(undef).
-spec disassemble(What) -> false | undef | Result when
What :: MFA | Address,
Result :: {Address, Code, MFA},
MFA :: mfa(),
Address :: non_neg_integer(),
Code :: binary().
disassemble(_) ->
erlang:nif_error(undef).
-spec display(Term) -> string() when
Term :: term().
display(_) ->
erlang:nif_error(undef).
-spec dist_ext_to_term(Tuple, Binary) -> term() when
Tuple :: tuple(),
Binary :: binary().
dist_ext_to_term(_, _) ->
erlang:nif_error(undef).
-spec dump_monitors(Id) -> true when
Id :: pid() | atom().
dump_monitors(_) ->
erlang:nif_error(undef).
-spec dump_links(Id) -> true when
Id :: pid() | port() | atom().
dump_links(_) ->
erlang:nif_error(undef).
-spec flat_size(Term) -> non_neg_integer() when
Term :: term().
flat_size(_) ->
erlang:nif_error(undef).
-spec size_shared(Term) -> non_neg_integer() when
Term :: term().
size_shared(_) ->
erlang:nif_error(undef).
-spec copy_shared(Term) -> term() when
Term :: term().
copy_shared(_) ->
erlang:nif_error(undef).
-spec get_internal_state(W) -> term() when
W :: reds_left | node_and_dist_references | monitoring_nodes
| next_pid | 'DbTable_words' | check_io_debug
| process_info_args | processes | processes_bif_info
| max_atom_out_cache_index | nbalance | available_internal_state
| force_heap_frags | memory
| {process_status, pid()}
| {link_list, pid() | port() | node()}
| {monitor_list, pid() | node()}
| {channel_number, non_neg_integer()}
| {have_pending_exit, pid() | port() | atom()}
| {binary_info, binary()}
| {term_to_binary_no_funs, term()}
| {dist_port, port()}
| {atom_out_cache_index, atom()}
| {fake_scheduler_bindings,
default_bind | spread | processor_spread | thread_spread
| thread_no_node_processor_spread | no_node_processor_spread
| no_node_thread_spread | no_spread | unbound}
| {reader_groups_map, non_neg_integer()}.
get_internal_state(_) ->
erlang:nif_error(undef).
-spec instructions() -> [string()].
instructions() ->
erlang:nif_error(undef).
-spec ic(F) -> Result when
F :: function(),
Result :: term().
ic(F) when is_function(F) ->
Is0 = erlang:system_info(instruction_counts),
R = F(),
Is1 = erlang:system_info(instruction_counts),
Is = lists:keysort(2,[{I,C1 - C0}||{{I,C1},{I,C0}} <- lists:zip(Is1,Is0)]),
_ = [io:format("~12w ~w~n", [C,I])||{I,C}<-Is],
io:format("Total: ~w~n",[lists:sum([C||{_I,C}<-Is])]),
R.
-spec lock_counters(info) -> term();
(clear) -> ok;
({copy_save, boolean()}) -> boolean();
({process_locks, boolean()}) -> boolean().
lock_counters(_) ->
erlang:nif_error(undef).
-spec same(Term1, Term2) -> boolean() when
Term1 :: term(),
Term2 :: term().
same(_, _) ->
erlang:nif_error(undef).
-spec set_internal_state(available_internal_state, boolean()) -> boolean();
(reds_left, non_neg_integer()) -> true;
(block, non_neg_integer()) -> true;
(sleep, non_neg_integer()) -> true;
(block_scheduler, non_neg_integer()) -> true;
(next_pid, non_neg_integer()) -> false | integer();
(force_gc, pid() | atom()) -> boolean();
(send_fake_exit_signal, {pid() | port(), pid(), term()}) -> dead | message | unaffected | exit;
(colliding_names, {atom(), non_neg_integer()}) ->
[atom()];
(binary_loop_limit, default) -> -1;
(binary_loop_limit, non_neg_integer()) -> non_neg_integer();
(re_loop_limit, default) -> -1;
(re_loop_limit, non_neg_integer()) -> non_neg_integer();
(unicode_loop_limit, default) -> -1;
(unicode_loop_limit, non_neg_integer()) -> non_neg_integer();
(hipe_test_reschedule_suspend, term()) -> nil();
(hipe_test_reschedule_resume, pid() | port()) -> boolean();
(test_long_gc_sleep, non_neg_integer()) -> true;
(kill_dist_connection, port()) -> boolean();
(not_running_optimization, boolean()) -> boolean();
(wait, deallocations) -> ok.
set_internal_state(_, _) ->
erlang:nif_error(undef).
%%% End of BIFs
%% size(Term)
%% Returns the size of Term in actual heap words. Shared subterms are
%% counted once. Example: If A = [a,b], B =[A,A] then size(B) returns 8,
%% while flat_size(B) returns 12.
-spec size(term()) -> non_neg_integer().
-record(s, {seen, maps}).
size(Term) ->
{Sum,_} = size(Term, #s{seen=gb_trees:empty(),maps=[]}, 0),
Sum.
size([H|T]=Term, Seen0, Sum0) ->
case remember_term(Term, Seen0) of
seen -> {Sum0,Seen0};
Seen1 ->
{Sum,Seen} = size(H, Seen1, Sum0+2),
size(T, Seen, Sum)
end;
size(Tuple, Seen0, Sum0) when is_tuple(Tuple) ->
case remember_term(Tuple, Seen0) of
seen -> {Sum0,Seen0};
Seen ->
Sum = Sum0 + 1 + tuple_size(Tuple),
tuple_size(1, tuple_size(Tuple), Tuple, Seen, Sum)
end;
size(Map, Seen0, Sum) when is_map(Map) ->
case remember_term(Map, Seen0) of
seen -> {Sum,Seen0};
Seen -> map_size(Map, Seen, Sum)
end;
size(Fun, Seen0, Sum) when is_function(Fun) ->
case remember_term(Fun, Seen0) of
seen -> {Sum,Seen0};
Seen -> fun_size(Fun, Seen, Sum)
end;
size(Term, Seen0, Sum) ->
case erts_debug:flat_size(Term) of
0 -> {Sum,Seen0};
Sz ->
case remember_term(Term, Seen0) of
seen -> {Sum,Seen0};
Seen -> {Sum+Sz,Seen}
end
end.
tuple_size(I, Sz, _, Seen, Sum) when I > Sz ->
{Sum,Seen};
tuple_size(I, Sz, Tuple, Seen0, Sum0) ->
{Sum,Seen} = size(element(I, Tuple), Seen0, Sum0),
tuple_size(I+1, Sz, Tuple, Seen, Sum).
map_size(Map,Seen0,Sum0) ->
%% Danger:
%% The internal nodes from erts_internal:map_hashmap_children/1
%% is not allowed to leak anywhere. They are only allowed in
%% containers (cons cells and tuples, not maps), in gc and
%% in erts_debug:same/2
case erts_internal:map_type(Map) of
flatmap ->
Kt = erts_internal:map_to_tuple_keys(Map),
Vs = maps:values(Map),
{Sum1,Seen1} = size(Kt,Seen0,Sum0),
fold_size(Vs,Seen1,Sum1+length(Vs)+3);
hashmap ->
Cs = erts_internal:map_hashmap_children(Map),
fold_size(Cs,Seen0,Sum0+length(Cs)+2);
hashmap_node ->
Cs = erts_internal:map_hashmap_children(Map),
fold_size(Cs,Seen0,Sum0+length(Cs)+1)
end.
fun_size(Fun, Seen, Sum) ->
case erlang:fun_info(Fun, type) of
{type,external} ->
{Sum + erts_debug:flat_size(Fun),Seen};
{type,local} ->
Sz = erts_debug:flat_size(fun() -> ok end),
{env,Env} = erlang:fun_info(Fun, env),
fold_size(Env, Seen, Sum+Sz+length(Env))
end.
fold_size([H|T], Seen0, Sum0) ->
{Sum,Seen} = size(H, Seen0, Sum0),
fold_size(T, Seen, Sum);
fold_size([], Seen, Sum) -> {Sum,Seen}.
remember_term(Term, #s{maps=Ms}=S) when is_map(Term) ->
case is_term_seen(Term, Ms) of
false -> S#s{maps=[Term|Ms]};
true -> seen
end;
remember_term(Term, #s{seen=T}=S) ->
case gb_trees:lookup(Term,T) of
none -> S#s{seen=gb_trees:insert(Term,[Term],T)};
{value,Terms} ->
case is_term_seen(Term, Terms) of
false -> S#s{seen=gb_trees:update(Term,[Term|Terms],T)};
true -> seen
end
end.
-spec is_term_seen(term(), [term()]) -> boolean().
is_term_seen(Term, [H|T]) ->
case erts_debug:same(Term, H) of
true -> true;
false -> is_term_seen(Term, T)
end;
is_term_seen(_, []) -> false.
%% df(Mod) -- Disassemble Mod to file Mod.dis.
%% df(Mod, Func) -- Disassemble Mod:Func/Any to file Mod_Func.dis.
%% df(Mod, Func, Arity) -- Disassemble Mod:Func/Arity to file Mod_Func_Arity.dis.
-type df_ret() :: 'ok' | {'error', {'badopen', module()}} | {'undef', module()}.
-spec df(module()) -> df_ret().
df(Mod) when is_atom(Mod) ->
try Mod:module_info(functions) of
Fs0 when is_list(Fs0) ->
Name = lists:concat([Mod, ".dis"]),
Fs = [{Mod,Func,Arity} || {Func,Arity} <- Fs0],
dff(Name, Fs)
catch _:_ -> {undef,Mod}
end.
-spec df(module(), atom()) -> df_ret().
df(Mod, Func) when is_atom(Mod), is_atom(Func) ->
try Mod:module_info(functions) of
Fs0 when is_list(Fs0) ->
Name = lists:concat([Mod, "_", Func, ".dis"]),
Fs = [{Mod,Func1,Arity} || {Func1,Arity} <- Fs0, Func1 =:= Func],
dff(Name, Fs)
catch _:_ -> {undef,Mod}
end.
-spec df(module(), atom(), arity()) -> df_ret().
df(Mod, Func, Arity) when is_atom(Mod), is_atom(Func) ->
try Mod:module_info(functions) of
Fs0 when is_list(Fs0) ->
Name = lists:concat([Mod, "_", Func, "_", Arity, ".dis"]),
Fs = [{Mod,Func1,Arity1} || {Func1,Arity1} <- Fs0,
Func1 =:= Func, Arity1 =:= Arity],
dff(Name, Fs)
catch _:_ -> {undef,Mod}
end.
dff(File, Fs) when is_pid(File), is_list(Fs) ->
lists:foreach(fun(Mfa) ->
disassemble_function(File, Mfa),
io:nl(File)
end, Fs);
dff(Name, Fs) when is_list(Name) ->
case file:open(Name, [write]) of
{ok,F} ->
try
dff(F, Fs)
after
_ = file:close(F)
end;
{error,Reason} ->
{error,{badopen,Reason}}
end.
disassemble_function(File, {_,_,_}=MFA) ->
cont_dis(File, erts_debug:disassemble(MFA), MFA).
cont_dis(_, false, _) -> ok;
cont_dis(File, {Addr,Str,MFA}, MFA) ->
io:put_chars(File, binary_to_list(Str)),
cont_dis(File, erts_debug:disassemble(Addr), MFA);
cont_dis(_, {_,_,_}, _) -> ok.
-spec map_info(Map) -> list() when
Map :: map().
map_info(_) ->
erlang:nif_error(undef).
