#!/usr/bin/env escript
%% -*- erlang -*-
%%! -pa ebin
-record(state, {run_hooks = dict:new(),
run_fold_hooks = dict:new(),
hooked_funs = dict:new(),
mfas = dict:new(),
specs = dict:new(),
module :: module(),
file :: filename:filename()}).
main([Dir]) ->
State =
filelib:fold_files(
Dir, ".+\.[eh]rl\$", false,
fun(FileIn, Res) ->
case get_forms(FileIn) of
{ok, Forms} ->
Tree = erl_syntax:form_list(Forms),
Mod = list_to_atom(filename:rootname(filename:basename(FileIn))),
Acc0 = analyze_form(Tree, Res#state{module = Mod, file = FileIn}),
erl_syntax_lib:fold(
fun(Form, Acc) ->
case erl_syntax:type(Form) of
application ->
case erl_syntax_lib:analyze_application(Form) of
{ejabberd_hooks, {run, N}}
when N == 2; N == 3 ->
analyze_run_hook(Form, Acc);
{ejabberd_hooks, {run_fold, N}}
when N == 3; N == 4 ->
analyze_run_fold_hook(Form, Acc);
{ejabberd_hooks, {add, N}}
when N == 4; N == 5 ->
analyze_run_fun(Form, Acc);
{gen_iq_handler, {add_iq_handler, 6}} ->
analyze_iq_handler(Form, Acc);
_ ->
Acc
end;
attribute ->
case catch erl_syntax_lib:analyze_attribute(Form) of
{spec, _} ->
analyze_type_spec(Form, Acc);
_ ->
Acc
end;
_ ->
Acc
end
end, Acc0, Tree);
_Err ->
Res
end
end, #state{}),
report_orphaned_funs(State),
RunDeps = build_deps(State#state.run_hooks, State#state.hooked_funs),
RunFoldDeps = build_deps(State#state.run_fold_hooks, State#state.hooked_funs),
emit_module(RunDeps, RunFoldDeps, State#state.specs, Dir, hooks_type_test).
analyze_form(_Form, State) ->
%% case catch erl_syntax_lib:analyze_forms(Form) of
%% Props when is_list(Props) ->
%% M = State#state.module,
%% MFAs = lists:foldl(
%% fun({F, A}, Acc) ->
%% dict:append({M, F}, A, Acc)
%% end, State#state.mfas,
%% proplists:get_value(functions, Props, [])),
%% State#state{mfas = MFAs};
%% _ ->
%% State
%% end.
State.
analyze_run_hook(Form, State) ->
[Hook|Tail] = erl_syntax:application_arguments(Form),
case atom_value(Hook, State) of
undefined ->
State;
HookName ->
Args = case Tail of
[_Host, Args0] -> Args0;
[Args0] ->
Args0
end,
Arity = erl_syntax:list_length(Args),
Hooks = dict:store({HookName, Arity},
{State#state.file, erl_syntax:get_pos(Hook)},
State#state.run_hooks),
State#state{run_hooks = Hooks}
end.
analyze_run_fold_hook(Form, State) ->
[Hook|Tail] = erl_syntax:application_arguments(Form),
case atom_value(Hook, State) of
undefined ->
State;
HookName ->
Args = case Tail of
[_Host, _Val, Args0] -> Args0;
[_Val, Args0] -> Args0
end,
Arity = erl_syntax:list_length(Args) + 1,
Hooks = dict:store({HookName, Arity},
{State#state.file, erl_syntax:get_pos(Form)},
State#state.run_fold_hooks),
State#state{run_fold_hooks = Hooks}
end.
analyze_run_fun(Form, State) ->
[Hook|Tail] = erl_syntax:application_arguments(Form),
case atom_value(Hook, State) of
undefined ->
State;
HookName ->
{Module, Fun, Seq} = case Tail of
[_Host, M, F, S] ->
{M, F, S};
[M, F, S] ->
{M, F, S}
end,
ModName = module_name(Module, State),
FunName = atom_value(Fun, State),
if ModName /= undefined, FunName /= undefined ->
Funs = dict:append(
HookName,
{ModName, FunName, integer_value(Seq, State),
{State#state.file, erl_syntax:get_pos(Form)}},
State#state.hooked_funs),
State#state{hooked_funs = Funs};
true ->
State
end
end.
analyze_iq_handler(Form, State) ->
[_Component, _Host, _NS, Module, Function, _IQDisc] =
erl_syntax:application_arguments(Form),
Mod = module_name(Module, State),
Fun = atom_value(Function, State),
if Mod /= undefined, Fun /= undefined ->
code:ensure_loaded(Mod),
case erlang:function_exported(Mod, Fun, 1) of
false ->
log("~s:~p: Error: function ~s:~s/1 is registered "
"as iq handler, but is not exported~n",
[State#state.file, erl_syntax:get_pos(Form),
Mod, Fun]);
true ->
ok
end;
true ->
ok
end,
State.
analyze_type_spec(Form, State) ->
case catch erl_syntax:revert(Form) of
{attribute, _, spec, {{F, A}, _}} ->
Specs = dict:store({State#state.module, F, A},
{Form, State#state.file},
State#state.specs),
State#state{specs = Specs};
_ ->
State
end.
build_deps(Hooks, Hooked) ->
dict:fold(
fun({Hook, Arity}, {_File, _LineNo} = Meta, Deps) ->
case dict:find(Hook, Hooked) of
{ok, Funs} ->
ExportedFuns =
lists:flatmap(
fun({M, F, Seq, {FunFile, FunLineNo} = FunMeta}) ->
code:ensure_loaded(M),
case erlang:function_exported(M, F, Arity) of
false ->
log("~s:~p: Error: function ~s:~s/~p "
"is hooked on ~s/~p, but is not "
"exported~n",
[FunFile, FunLineNo, M, F,
Arity, Hook, Arity]),
[];
true ->
[{{M, F, Arity}, Seq, FunMeta}]
end
end, Funs),
dict:append_list({Hook, Arity, Meta}, ExportedFuns, Deps);
error ->
%% log("~s:~p: Warning: hook ~p/~p is unused~n",
%% [_File, _LineNo, Hook, Arity]),
dict:append_list({Hook, Arity, Meta}, [], Deps)
end
end, dict:new(), Hooks).
report_orphaned_funs(State) ->
dict:map(
fun(Hook, Funs) ->
lists:foreach(
fun({M, F, _, {File, Line}}) ->
case get_fun_arities(M, F, State) of
[] ->
log("~s:~p: Error: function ~s:~s is "
"hooked on hook ~s, but is not exported~n",
[File, Line, M, F, Hook]);
Arities ->
case lists:any(
fun(Arity) ->
dict:is_key({Hook, Arity},
State#state.run_hooks) orelse
dict:is_key({Hook, Arity},
State#state.run_fold_hooks);
(_) ->
false
end, Arities) of
false ->
Arity = hd(Arities),
log("~s:~p: Error: function ~s:~s/~p is hooked"
" on non-existent hook ~s/~p~n",
[File, Line, M, F, Arity, Hook, Arity]);
true ->
ok
end
end
end, Funs)
end, State#state.hooked_funs).
get_fun_arities(Mod, Fun, _State) ->
proplists:get_all_values(Fun, Mod:module_info(exports)).
module_name(Form, State) ->
try
Name = erl_syntax:macro_name(Form),
'MODULE' = erl_syntax:variable_name(Name),
State#state.module
catch _:_ ->
atom_value(Form, State)
end.
atom_value(Form, State) ->
case erl_syntax:type(Form) of
atom ->
erl_syntax:atom_value(Form);
_ ->
log("~s:~p: Warning: not an atom: ~s~n",
[State#state.file,
erl_syntax:get_pos(Form),
erl_prettypr:format(Form)]),
undefined
end.
integer_value(Form, State) ->
case erl_syntax:type(Form) of
integer ->
erl_syntax:integer_value(Form);
_ ->
log("~s:~p: Warning: not an integer: ~s~n",
[State#state.file,
erl_syntax:get_pos(Form),
erl_prettypr:format(Form)]),
0
end.
emit_module(RunDeps, RunFoldDeps, Specs, Dir, Module) ->
File = filename:join([Dir, Module]) ++ ".erl",
try
{ok, Fd} = file:open(File, [write]),
write(Fd, "-module(~s).~n~n", [Module]),
emit_export(Fd, RunDeps, "run hooks"),
emit_export(Fd, RunFoldDeps, "run_fold hooks"),
emit_run_hooks(Fd, RunDeps, Specs),
emit_run_fold_hooks(Fd, RunFoldDeps, Specs),
write(Fd, "bypass_stop({stop, Acc}) -> Acc;~n"
"bypass_stop(Acc) -> Acc.~n", []),
file:close(Fd),
log("Module written to file ~s~n", [File])
catch _:{badmatch, {error, Reason}} ->
log("writing to ~s failed: ~s", [File, file:format_error(Reason)])
end.
emit_run_hooks(Fd, Deps, Specs) ->
DepsList = lists:sort(dict:to_list(Deps)),
lists:foreach(
fun({{Hook, Arity, {File, LineNo}}, []}) ->
Args = lists:duplicate(Arity, "_"),
write(Fd, "%% called at ~s:~p~n", [File, LineNo]),
write(Fd, "~s(~s) -> ok.~n~n", [Hook, string:join(Args, ", ")]);
({{Hook, Arity, {File, LineNo}}, Funs}) ->
emit_specs(Fd, Funs, Specs),
write(Fd, "%% called at ~s:~p~n", [File, LineNo]),
Args = string:join(
[[N] || N <- lists:sublist(lists:seq($A, $Z), Arity)],
", "),
write(Fd, "~s(~s) ->~n ", [Hook, Args]),
Calls = [io_lib:format("~s:~s(~s)", [Mod, Fun, Args])
|| {{Mod, Fun, _}, _Seq, _} <- lists:keysort(2, Funs)],
write(Fd, "~s.~n~n", [string:join(Calls, ",\n ")])
end, DepsList).
emit_run_fold_hooks(Fd, Deps, Specs) ->
DepsList = lists:sort(dict:to_list(Deps)),
lists:foreach(
fun({{Hook, Arity, {File, LineNo}}, []}) ->
write(Fd, "%% called at ~s:~p~n", [File, LineNo]),
Args = ["Acc"|lists:duplicate(Arity - 1, "_")],
write(Fd, "~s(~s) -> Acc.~n~n", [Hook, string:join(Args, ", ")]);
({{Hook, Arity, {File, LineNo}}, Funs}) ->
emit_specs(Fd, Funs, Specs),
write(Fd, "%% called at ~s:~p~n", [File, LineNo]),
Args = [[N] || N <- lists:sublist(lists:seq($A, $Z), Arity - 1)],
write(Fd, "~s(~s) ->", [Hook, string:join(["Acc"|Args], ", ")]),
FunsCascade = make_funs_cascade(
lists:reverse(lists:keysort(2, Funs)),
1, Args),
write(Fd, "~s.~n~n", [FunsCascade])
end, DepsList).
make_funs_cascade([{{Mod, Fun, _}, _Seq, _}|Funs], N, Args) ->
io_lib:format("~n~sbypass_stop(~s:~s(~s))",
[lists:duplicate(N, " "),
Mod, Fun, string:join([make_funs_cascade(Funs, N+1, Args)|Args], ", ")]);
make_funs_cascade([], _N, _Args) ->
"Acc".
emit_export(Fd, Deps, Comment) ->
DepsList = lists:sort(dict:to_list(Deps)),
Exports = lists:map(
fun({{Hook, Arity, _}, _}) ->
io_lib:format("~s/~p", [Hook, Arity])
end, DepsList),
write(Fd, "%% ~s~n-export([~s]).~n~n",
[Comment, string:join(Exports, ",\n ")]).
emit_specs(Fd, Funs, Specs) ->
lists:foreach(
fun({{M, _, _} = MFA, _, _}) ->
case dict:find(MFA, Specs) of
{ok, {Form, _File}} ->
Lines = string:tokens(erl_syntax:get_ann(Form), "\n"),
lists:foreach(
fun("%" ++ _) ->
ok;
("-spec" ++ Spec) ->
write(Fd, "%% -spec ~p:~s~n",
[M, string:strip(Spec, left)]);
(Line) ->
write(Fd, "%% ~s~n", [Line])
end, Lines);
error ->
ok
end
end, lists:keysort(2, Funs)).
get_forms(Path) ->
case file:open(Path, [read]) of
{ok, Fd} ->
parse(Path, Fd, 1, []);
Err ->
Err
end.
parse(Path, Fd, Line, Acc) ->
{ok, Pos} = file:position(Fd, cur),
case epp_dodger:parse_form(Fd, Line) of
{ok, Form, NewLine} ->
{ok, NewPos} = file:position(Fd, cur),
{ok, RawForm} = file:pread(Fd, Pos, NewPos - Pos),
file:position(Fd, {bof, NewPos}),
AnnForm = erl_syntax:set_ann(Form, RawForm),
parse(Path, Fd, NewLine, [AnnForm|Acc]);
{eof, _} ->
{ok, NewPos} = file:position(Fd, cur),
if NewPos > Pos ->
{ok, RawForm} = file:pread(Fd, Pos, NewPos - Pos),
Form = erl_syntax:text(""),
AnnForm = erl_syntax:set_ann(Form, RawForm),
{ok, lists:reverse([AnnForm|Acc])};
true ->
{ok, lists:reverse(Acc)}
end;
{error, {_, _, ErrDesc}, LineNo} = Err ->
log("~s:~p: Error: ~s~n",
[Path, LineNo, erl_parse:format_error(ErrDesc)]),
Err
end.
log(Format, Args) ->
io:format(standard_io, Format, Args).
write(Fd, Format, Args) ->
file:write(Fd, io_lib:format(Format, Args)).
