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-rw-r--r--lib/debugger/src/dbg_istk.erl245
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diff --git a/lib/debugger/src/dbg_istk.erl b/lib/debugger/src/dbg_istk.erl
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+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 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
+%% 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_istk).
+-export([init/0,delayed_to_external/0,from_external/1,
+ push/3,pop/0,pop/1,stack_level/0,
+ delayed_stacktrace/0,delayed_stacktrace/2,
+ bindings/1,stack_frame/2,backtrace/2,
+ in_use_p/2]).
+
+-include("dbg_ieval.hrl").
+
+-define(STACK, ?MODULE).
+
+-record(e,
+ {level, %Level
+ mfa, %{Mod,Func,Args|Arity}|{Fun,Args}
+ line, %Line called from
+ bindings,
+ lc %Last call (true|false)
+ }).
+
+init() ->
+ init([]).
+
+delayed_to_external() ->
+ Stack = get(?STACK),
+ fun() -> {stack,term_to_binary(Stack)} end.
+
+from_external({stack,Stk}) ->
+ put(?STACK, binary_to_term(Stk)).
+
+init(Stack) ->
+ put(?STACK, Stack).
+
+%% We keep track of a call stack that is used for
+%% 1) saving stack frames that can be inspected from an Attached
+%% Process GUI (using dbg_icmd:get(Meta, stack_frame, {Dir, SP})
+%% 2) generate an approximation of regular stacktrace -- sent to
+%% Debugged when it should raise an exception or evaluate a
+%% function (since it might possible raise an exception)
+%%
+%% How to push depends on the "Stack Trace" option (value saved in
+%% process dictionary item 'trace_stack').
+%% all - everything is pushed
+%% no_tail - tail recursive push
+%% false - nothing is pushed
+%% Whenever a function returns, the corresponding call frame is popped.
+
+push(Bs, #ieval{level=Le,module=Mod,function=Name,
+ arguments=As,line=Li}=Ieval, Lc) ->
+ Entry = #e{level=Le,mfa={Mod,Name,As},line=Li,bindings=Bs,lc=Lc},
+ case get(trace_stack) of
+ false ->
+ Ieval#ieval{level=Le+1};
+ no_tail when Lc ->
+ Ieval;
+ _ -> % all | no_tail when Lc =:= false
+ put(?STACK, [Entry|get(?STACK)]),
+ Ieval#ieval{level=Le+1}
+ end.
+
+pop() ->
+ case get(trace_stack) of
+ false -> ignore;
+ _ -> % all ¦ no_tail
+ case get(?STACK) of
+ [_Entry|Entries] ->
+ put(?STACK, Entries);
+ [] ->
+ ignore
+ end
+ end.
+
+pop(Le) ->
+ case get(trace_stack) of
+ false -> ignore;
+ _ -> % all | no_tail
+ put(?STACK, pop(Le, get(?STACK)))
+ end.
+
+pop(Level, [#e{level=Le}|Stack]) when Level =< Le ->
+ pop(Level, Stack);
+pop(_Level, Stack) ->
+ Stack.
+
+%% stack_level() -> Le
+%% stack_level(Stack) -> Le
+%% Top call level
+stack_level() ->
+ stack_level(get(?STACK)).
+
+stack_level([]) -> 1;
+stack_level([#e{level=Le}|_]) -> Le.
+
+%% delayed_stacktrace() -> CreateStacktraceFun
+%% delayed_stacktrace(ArgFlag, #ieval{}) -> CreateStacktraceFun
+%% ArgFlag = no_args | include_args
+%% CreateStacktraceFun = fun(NumberOfEntries)
+%%
+%% Return a fun that can convert the internal stack format to
+%% an imitation of the regular stacktrace.
+
+delayed_stacktrace() ->
+ Stack0 = get(?STACK),
+ fun(NumEntries) ->
+ Stack = stacktrace(NumEntries, Stack0, []),
+ [finalize(ArityOnly) || {ArityOnly,_} <- Stack]
+ end.
+
+delayed_stacktrace(include_args, Ieval) ->
+ #ieval{module=Mod,function=Name,arguments=As,line=Li} = Ieval,
+ Stack0 = [#e{mfa={Mod,Name,As},line=Li}|get(?STACK)],
+ fun(NumEntries) ->
+ case stacktrace(NumEntries, Stack0, []) of
+ [] ->
+ [];
+ [{_,WithArgs}|Stack] ->
+ [finalize(WithArgs) |
+ [finalize(ArityOnly) || {ArityOnly,_} <- Stack]]
+ end
+ end;
+delayed_stacktrace(no_args, Ieval) ->
+ #ieval{module=Mod,function=Name,arguments=As,line=Li} = Ieval,
+ Stack0 = [#e{mfa={Mod,Name,As},line=Li}|get(?STACK)],
+ fun(NumEntries) ->
+ Stack = stacktrace(NumEntries, Stack0, []),
+ [finalize(ArityOnly) || {ArityOnly,_} <- Stack]
+ end.
+
+stacktrace(N, [#e{lc=true}|T], Acc) ->
+ stacktrace(N, T, Acc);
+stacktrace(N, [E|T], []) ->
+ stacktrace(N-1, T, [normalize(E)]);
+stacktrace(N, [E|T], [{P,_}|_]=Acc) when N > 0 ->
+ case normalize(E) of
+ {P,_} ->
+ stacktrace(N, T, Acc);
+ New ->
+ stacktrace(N-1, T, [New|Acc])
+ end;
+stacktrace(_, _, Acc) ->
+ lists:reverse(Acc).
+
+normalize(#e{mfa={M,Fun,As},line=Li}) when is_function(Fun) ->
+ Loc = {M,Li},
+ {{Fun,length(As),Loc},{Fun,As,Loc}};
+normalize(#e{mfa={M,F,As},line=Li}) ->
+ Loc = {M,Li},
+ {{M,F,length(As),Loc},{M,F,As,Loc}}.
+
+finalize({M,F,A,Loc}) -> {M,F,A,line(Loc)};
+finalize({Fun,A,Loc}) -> {Fun,A,line(Loc)}.
+
+line({Mod,Line}) when Line > 0 ->
+ [{file,atom_to_list(Mod)++".erl"},{line,Line}];
+line(_) -> [].
+
+%% bindings(SP) -> Bs
+%% SP = Le % stack pointer
+%% Return the bindings for the specified call level
+bindings(SP) ->
+ bindings(SP, get(?STACK)).
+
+bindings(SP, [#e{level=SP,bindings=Bs}|_]) ->
+ Bs;
+bindings(SP, [_Entry|Entries]) ->
+ bindings(SP, Entries);
+bindings(_SP, []) ->
+ erl_eval:new_bindings().
+
+%% stack_frame(Dir, SP) -> {Le, Where, Bs} | top | bottom
+%% Dir = up | down
+%% Where = {Cm, Li}
+%% Cm = Module | undefined % module
+%% Li = int() | -1 % line number
+%% Bs = bindings()
+%% Return stack frame info one step up/down from given stack pointer
+%% up = to lower call levels
+%% down = to higher call levels
+stack_frame(up, SP) ->
+ stack_frame(SP, up, get(?STACK));
+stack_frame(down, SP) ->
+ stack_frame(SP, down, lists:reverse(get(?STACK))).
+
+stack_frame(SP, up, [#e{level=Le,mfa={Cm,_,_},line=Li,bindings=Bs}|_])
+ when Le < SP ->
+ {Le,{Cm,Li},Bs};
+stack_frame(SP, down, [#e{level=Le,mfa={Cm,_,_},line=Li,bindings=Bs}|_])
+ when Le > SP ->
+ {Le,{Cm,Li},Bs};
+stack_frame(SP, Dir, [#e{level=SP}|Stack]) ->
+ case Stack of
+ [#e{level=Le,mfa={Cm,_,_},line=Li,bindings=Bs}|_] ->
+ {Le,{Cm,Li},Bs};
+ [] when Dir =:= up ->
+ top;
+ [] when Dir =:= down ->
+ bottom
+ end;
+stack_frame(SP, Dir, [_Entry|Stack]) ->
+ stack_frame(SP, Dir, Stack).
+
+%% backtrace(HowMany) -> Backtrace
+%% HowMany = all | int()
+%% Backtrace = {Le, MFA}
+%% Return all/the last N called functions, in reversed call order
+backtrace(HowMany, Ieval) ->
+ #ieval{level=Level,module=Mod,function=Name,arguments=As} = Ieval,
+ Stack0 = [#e{level=Level,mfa={Mod,Name,As}}|get(?STACK)],
+ Stack = case HowMany of
+ all -> Stack0;
+ N -> lists:sublist(Stack0, N)
+ end,
+ [{Le,MFA} || #e{level=Le,mfa=MFA} <- Stack].
+
+%%--------------------------------------------------------------------
+%% in_use_p(Mod, Cm) -> boolean()
+%% Mod = Cm = atom()
+%% Returns true if Mod is found on the stack, otherwise false.
+%%--------------------------------------------------------------------
+in_use_p(Mod, Mod) -> true;
+in_use_p(Mod, _Cm) ->
+ case get(trace_stack) of
+ false -> true;
+ _ -> % all | no_tail
+ lists:any(fun(#e{mfa={M,_,_}}) when M =:= Mod -> true;
+ (_) -> false
+ end, get(?STACK))
+ end.
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-02 06:42:34 +0000