%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2007-2010. 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%
-module(escript).
%% Useful functions that can be called from scripts.
-export([script_name/0, foldl/3]).
%% Internal API.
-export([start/0, start/1]).
-record(state, {file,
module,
forms_or_bin,
source,
n_errors,
mode,
exports_main,
has_records}).
script_name() ->
[ScriptName|_] = init:get_plain_arguments(),
ScriptName.
%% Apply Fun(Name, GetInfo, GetBin, Acc) for each file in the escript.
%%
%% Fun/2 must return a new accumulator which is passed to the next call.
%% The function returns the final value of the accumulator. Acc0 is
%% returned if the escript contain an empty archive.
%%
%% GetInfo/0 is a fun that returns a #file_info{} record for the file.
%% GetBin/0 is a fun that returns a the contents of the file as a binary.
%%
%% An escript may contain erlang code, beam code or an archive:
%%
%% archive - the Fun/2 will be applied for each file in the archive
%% beam - the Fun/2 will be applied once and GetInfo/0 returns the file
%% info for the (entire) escript file
%% erl - the Fun/2 will be applied once, GetInfo/0 returns the file
%% info for the (entire) escript file and the GetBin returns
%% the compiled beam code
%%-spec foldl(fun((string(),
%% fun(() -> #file_info()),
%% fun(() -> binary() -> term()),
%% term()) -> term()),
%% term(),
%% string()).
foldl(Fun, Acc0, File) when is_function(Fun, 4) ->
case parse_file(File, false) of
{text, _, Forms, _Mode} when is_list(Forms) ->
GetInfo = fun() -> file:read_file_info(File) end,
GetBin =
fun() ->
case compile:forms(Forms, [return_errors, debug_info]) of
{ok, _, BeamBin} ->
BeamBin;
{error, _Errors, _Warnings} ->
fatal("There were compilation errors.")
end
end,
try
{ok, Fun(".", GetInfo, GetBin, Acc0)}
catch
throw:Reason ->
{error, Reason}
end;
{beam, _, BeamBin, _Mode} when is_binary(BeamBin) ->
GetInfo = fun() -> file:read_file_info(File) end,
GetBin = fun() -> BeamBin end,
try
{ok, Fun(".", GetInfo, GetBin, Acc0)}
catch
throw:Reason ->
{error, Reason}
end;
{archive, _, ArchiveBin, _Mode} when is_binary(ArchiveBin) ->
ZipFun =
fun({Name, GetInfo, GetBin}, A) ->
A2 = Fun(Name, GetInfo, GetBin, A),
{true, false, A2}
end,
case prim_zip:open(ZipFun, Acc0, {File, ArchiveBin}) of
{ok, PrimZip, Res} ->
ok = prim_zip:close(PrimZip),
{ok, Res};
{error, bad_eocd} ->
{error, "Not an archive file"};
{error, Reason} ->
{error, Reason}
end
end.
%%
%% Internal API.
%%
start() ->
start([]).
start(EscriptOptions) ->
try
%% Commands run using -run or -s are run in a process
%% trap_exit set to false. Because this behaviour is
%% surprising for users of escript, make sure to reset
%% trap_exit to false.
process_flag(trap_exit, false),
case init:get_plain_arguments() of
[File|Args] ->
parse_and_run(File, Args, EscriptOptions);
[] ->
io:format("escript: Missing filename\n", []),
my_halt(127)
end
catch
throw:Str ->
io:format("escript: ~s\n", [Str]),
my_halt(127);
_:Reason ->
io:format("escript: Internal error: ~p\n", [Reason]),
io:format("~p\n", [erlang:get_stacktrace()]),
my_halt(127)
end.
parse_and_run(File, Args, Options) ->
CheckOnly = lists:member("s", Options),
{Source, Module, FormsOrBin, HasRecs, Mode} =
parse_file(File, CheckOnly),
Mode2 =
case lists:member("d", Options) of
true ->
debug;
false ->
case lists:member("c", Options) of
true ->
compile;
false ->
case lists:member("i", Options) of
true -> interpret;
false -> Mode
end
end
end,
if
is_list(FormsOrBin) ->
case Mode2 of
interpret ->
interpret(FormsOrBin, HasRecs, File, Args);
compile ->
case compile:forms(FormsOrBin, [report]) of
{ok, Module, BeamBin} ->
{module, Module} = code:load_binary(Module, File, BeamBin),
run(Module, Args);
_Other ->
fatal("There were compilation errors.")
end;
debug ->
case compile:forms(FormsOrBin, [report, debug_info]) of
{ok,Module,BeamBin} ->
{module, Module} = code:load_binary(Module, File, BeamBin),
debug(Module, {Module, File, File, BeamBin}, Args);
_Other ->
fatal("There were compilation errors.")
end
end;
is_binary(FormsOrBin) ->
case Source of
archive ->
{ok, FileInfo} = file:read_file_info(File),
case code:set_primary_archive(File, FormsOrBin, FileInfo) of
ok when CheckOnly ->
case code:load_file(Module) of
{module, _} ->
case erlang:function_exported(Module, main, 1) of
true ->
my_halt(0);
false ->
Text = lists:concat(["Function ", Module, ":main/1 is not exported"]),
fatal(Text)
end;
_ ->
Text = lists:concat(["Cannot load module ", Module, " from archive"]),
fatal(Text)
end;
ok ->
case Mode2 of
run -> run(Module, Args);
debug -> debug(Module, Module, Args)
end;
{error, bad_eocd} ->
fatal("Not an archive file");
{error, Reason} ->
fatal(Reason)
end;
beam ->
case Mode2 of
run ->
{module, Module} = code:load_binary(Module, File, FormsOrBin),
run(Module, Args);
debug ->
[Base | Rest] = lists:reverse(filename:split(File)),
Base2 = filename:basename(Base, code:objfile_extension()),
Rest2 =
case Rest of
["ebin" | Top] -> ["src" | Top];
_ -> Rest
end,
SrcFile = filename:join(lists:reverse([Base2 ++ ".erl" | Rest2])),
debug(Module, {Module, SrcFile, File, FormsOrBin}, Args)
end
end
end.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Parse script
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
parse_file(File, CheckOnly) ->
S = #state{file = File,
n_errors = 0,
mode = interpret,
exports_main = false,
has_records = false},
{ok, Fd} =
case file:open(File, [read]) of
{ok, Fd0} ->
{ok, Fd0};
{error, R} ->
fatal(lists:concat([file:format_error(R), ": '", File, "'"]))
end,
{HeaderSz, StartLine, ScriptType} = skip_header(Fd, 1),
#state{mode = Mode,
source = Source,
module = Module,
forms_or_bin = FormsOrBin,
has_records = HasRecs} =
case ScriptType of
archive ->
%% Archive file
ok = file:close(Fd),
parse_archive(S, File, HeaderSz);
beam ->
%% Beam file
ok = file:close(Fd),
parse_beam(S, File, HeaderSz, CheckOnly);
source ->
%% Source code
parse_source(S, File, Fd, StartLine, HeaderSz, CheckOnly)
end,
{Source, Module, FormsOrBin, HasRecs, Mode}.
%% Skip header and make a heuristic guess about the script type
skip_header(P, LineNo) ->
%% Skip shebang on first line
{ok, HeaderSz0} = file:position(P, cur),
Line1 = get_line(P),
case classify_line(Line1) of
shebang ->
find_first_body_line(P, LineNo);
archive ->
{HeaderSz0, LineNo, archive};
beam ->
{HeaderSz0, LineNo, beam};
_ ->
find_first_body_line(P, LineNo)
end.
find_first_body_line(P, LineNo) ->
{ok, HeaderSz1} = file:position(P, cur),
%% Look for special comment on second line
Line2 = get_line(P),
{ok, HeaderSz2} = file:position(P, cur),
case classify_line(Line2) of
emu_args ->
%% Skip special comment on second line
Line3 = get_line(P),
{HeaderSz2, LineNo + 2, guess_type(Line3)};
_ ->
%% Look for special comment on third line
Line3 = get_line(P),
{ok, HeaderSz3} = file:position(P, cur),
case classify_line(Line3) of
emu_args ->
%% Skip special comment on third line
Line4 = get_line(P),
{HeaderSz3, LineNo + 3, guess_type(Line4)};
_ ->
%% Just skip shebang on first line
{HeaderSz1, LineNo + 1, guess_type(Line2)}
end
end.
classify_line(Line) ->
case Line of
[$\#, $\! | _] ->
shebang;
[$P, $K | _] ->
archive;
[$F, $O, $R, $1 | _] ->
beam;
[$\%, $\%, $\! | _] ->
emu_args;
_ ->
undefined
end.
guess_type(Line) ->
case classify_line(Line) of
archive -> archive;
beam -> beam;
_ -> source
end.
get_line(P) ->
case io:get_line(P, '') of
eof ->
fatal("Premature end of file reached");
Line ->
Line
end.
parse_archive(S, File, HeaderSz) ->
case file:read_file(File) of
{ok, <<_FirstLine:HeaderSz/binary, Bin/binary>>} ->
Mod =
case init:get_argument(escript) of
{ok, [["main", M]]} ->
%% Use explicit module name
list_to_atom(M);
_ ->
%% Use escript name without extension as module name
RevBase = lists:reverse(filename:basename(File)),
RevBase2 =
case lists:dropwhile(fun(X) -> X =/= $. end, RevBase) of
[$. | Rest] -> Rest;
[] -> RevBase
end,
list_to_atom(lists:reverse(RevBase2))
end,
S#state{source = archive,
mode = run,
module = Mod,
forms_or_bin = Bin};
{ok, _} ->
fatal("Illegal archive format");
{error, Reason} ->
fatal(file:format_error(Reason))
end.
parse_beam(S, File, HeaderSz, CheckOnly) ->
{ok, <<_FirstLine:HeaderSz/binary, Bin/binary>>} =
file:read_file(File),
case beam_lib:chunks(Bin, [exports]) of
{ok, {Module, [{exports, Exports}]}} ->
case CheckOnly of
true ->
case lists:member({main, 1}, Exports) of
true ->
my_halt(0);
false ->
Text = lists:concat(["Function ", Module, ":main/1 is not exported"]),
fatal(Text)
end;
false ->
S#state{source = beam,
mode = run,
module = Module,
forms_or_bin = Bin}
end;
{error, beam_lib, Reason} when is_tuple(Reason) ->
fatal(element(1, Reason));
{error, beam_lib, Reason} ->
fatal(Reason)
end.
parse_source(S, File, Fd, StartLine, HeaderSz, CheckOnly) ->
{PreDefMacros, Module} = pre_def_macros(File),
IncludePath = [],
{ok, _} = file:position(Fd, {bof, HeaderSz}),
case epp:open(File, Fd, StartLine, IncludePath, PreDefMacros) of
{ok, Epp} ->
{ok, FileForm} = epp:parse_erl_form(Epp),
OptModRes = epp:parse_erl_form(Epp),
S2 = S#state{source = text, module = Module},
S3 =
case OptModRes of
{ok, {attribute,_, module, M} = Form} ->
epp_parse_file(Epp, S2#state{module = M}, [Form, FileForm]);
{ok, _} ->
ModForm = {attribute,1,module, Module},
epp_parse_file2(Epp, S2, [ModForm, FileForm], OptModRes);
{error, _} ->
epp_parse_file2(Epp, S2, [FileForm], OptModRes);
{eof,LastLine} ->
S#state{forms_or_bin = [FileForm, {eof,LastLine}]}
end,
ok = epp:close(Epp),
ok = file:close(Fd),
check_source(S3, CheckOnly);
{error, Reason} ->
io:format("escript: ~p\n", [Reason]),
fatal("Preprocessor error")
end.
check_source(S, CheckOnly) ->
case S of
#state{n_errors = Nerrs} when Nerrs =/= 0 ->
fatal("There were compilation errors.");
#state{exports_main = ExpMain,
forms_or_bin = [FileForm2, ModForm2 | Forms]} ->
%% Optionally add export of main/1
Forms2 =
case ExpMain of
false -> [{attribute,0,export, [{main,1}]} | Forms];
true -> Forms
end,
Forms3 = [FileForm2, ModForm2 | Forms2],
case CheckOnly of
true ->
%% Strong validation and halt
case compile:forms(Forms3, [report,strong_validation]) of
{ok,_} ->
my_halt(0);
_Other ->
fatal("There were compilation errors.")
end;
false ->
S#state{forms_or_bin = Forms3}
end
end.
pre_def_macros(File) ->
{MegaSecs, Secs, MicroSecs} = erlang:now(),
Replace = fun(Char) ->
case Char of
$\. -> $\_;
_ -> Char
end
end,
CleanBase = lists:map(Replace, filename:basename(File)),
ModuleStr =
CleanBase ++ "__" ++
"escript__" ++
integer_to_list(MegaSecs) ++ "__" ++
integer_to_list(Secs) ++ "__" ++
integer_to_list(MicroSecs),
Module = list_to_atom(ModuleStr),
PreDefMacros = [{'MODULE', Module, redefine},
{'MODULE_STRING', ModuleStr, redefine}],
{PreDefMacros, Module}.
epp_parse_file(Epp, S, Forms) ->
Parsed = epp:parse_erl_form(Epp),
epp_parse_file2(Epp, S, Forms, Parsed).
epp_parse_file2(Epp, S, Forms, Parsed) ->
%% io:format("~p\n", [Parsed]),
case Parsed of
{ok, Form} ->
case Form of
{attribute,_,record, _} ->
S2 = S#state{has_records = true},
epp_parse_file(Epp, S2, [Form | Forms]);
{attribute,Ln,mode,NewMode} ->
S2 = S#state{mode = NewMode},
if
NewMode =:= compile; NewMode =:= interpret; NewMode =:= debug ->
epp_parse_file(Epp, S2, [Form | Forms]);
true ->
Args = lists:flatten(io_lib:format("illegal mode attribute: ~p", [NewMode])),
io:format("~s:~w ~s\n", [S#state.file,Ln,Args]),
Error = {error,{Ln,erl_parse,Args}},
Nerrs= S#state.n_errors + 1,
epp_parse_file(Epp, S2#state{n_errors = Nerrs}, [Error | Forms])
end;
{attribute,_,export,Fs} ->
case lists:member({main,1}, Fs) of
false ->
epp_parse_file(Epp, S, [Form | Forms]);
true ->
epp_parse_file(Epp, S#state{exports_main = true}, [Form | Forms])
end;
_ ->
epp_parse_file(Epp, S, [Form | Forms])
end;
{error,{Ln,Mod,Args}} = Form ->
io:format("~s:~w: ~s\n",
[S#state.file,Ln,Mod:format_error(Args)]),
epp_parse_file(Epp, S#state{n_errors = S#state.n_errors + 1}, [Form | Forms]);
{eof,LastLine} ->
S#state{forms_or_bin = lists:reverse([{eof, LastLine} | Forms])}
end.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Evaluate script
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
debug(Module, AbsMod, Args) ->
case hidden_apply(debugger, debugger, start, []) of
{ok, _} ->
case hidden_apply(debugger, int, i, [AbsMod]) of
{module, _} ->
hidden_apply(debugger, debugger, auto_attach, [[init]]),
run(Module, Args);
error ->
Text = lists:concat(["Cannot load the code for ", Module, " into the debugger"]),
fatal(Text)
end;
_ ->
fatal("Cannot start the debugger")
end.
run(Module, Args) ->
try
Module:main(Args),
my_halt(0)
catch
Class:Reason ->
fatal(format_exception(Class, Reason))
end.
interpret(Forms, HasRecs, File, Args) ->
%% Basic validation before execution
case erl_lint:module(Forms) of
{ok,Ws} ->
report_warnings(Ws);
{error,Es,Ws} ->
report_errors(Es),
report_warnings(Ws),
fatal("There were compilation errors.")
end,
%% Optionally expand records
Forms2 =
case HasRecs of
false -> Forms;
true -> erl_expand_records:module(Forms, [])
end,
Dict = parse_to_dict(Forms2),
ArgsA = erl_parse:abstract(Args, 0),
Call = {call,0,{atom,0,main},[ArgsA]},
try
erl_eval:expr(Call,
erl_eval:new_bindings(),
{value,fun(I, J) -> code_handler(I, J, Dict, File) end}),
my_halt(0)
catch
Class:Reason ->
fatal(format_exception(Class, Reason))
end.
report_errors(Errors) ->
lists:foreach(fun ({{F,_L},Eds}) -> list_errors(F, Eds);
({F,Eds}) -> list_errors(F, Eds) end,
Errors).
list_errors(F, [{Line,Mod,E}|Es]) ->
io:fwrite("~s:~w: ~s\n", [F,Line,Mod:format_error(E)]),
list_errors(F, Es);
list_errors(F, [{Mod,E}|Es]) ->
io:fwrite("~s: ~s\n", [F,Mod:format_error(E)]),
list_errors(F, Es);
list_errors(_F, []) -> ok.
report_warnings(Ws0) ->
Ws1 = lists:flatmap(fun({{F,_L},Eds}) -> format_message(F, Eds);
({F,Eds}) -> format_message(F, Eds) end,
Ws0),
Ws = ordsets:from_list(Ws1),
lists:foreach(fun({_,Str}) -> io:put_chars(Str) end, Ws).
format_message(F, [{Line,Mod,E}|Es]) ->
M = {{F,Line},io_lib:format("~s:~w: Warning: ~s\n", [F,Line,Mod:format_error(E)])},
[M|format_message(F, Es)];
format_message(F, [{Mod,E}|Es]) ->
M = {none,io_lib:format("~s: Warning: ~s\n", [F,Mod:format_error(E)])},
[M|format_message(F, Es)];
format_message(_, []) -> [].
parse_to_dict(L) -> parse_to_dict(L, dict:new()).
parse_to_dict([{function,_,Name,Arity,Clauses}|T], Dict0) ->
Dict = dict:store({local, Name,Arity}, Clauses, Dict0),
parse_to_dict(T, Dict);
parse_to_dict([{attribute,_,import,{Mod,Funcs}}|T], Dict0) ->
Dict = lists:foldl(fun(I, D) ->
dict:store({remote,I}, Mod, D)
end, Dict0, Funcs),
parse_to_dict(T, Dict);
parse_to_dict([_|T], Dict) ->
parse_to_dict(T, Dict);
parse_to_dict([], Dict) ->
Dict.
code_handler(local, [file], _, File) ->
File;
code_handler(Name, Args, Dict, File) ->
%%io:format("code handler=~p~n",[{Name, Args}]),
Arity = length(Args),
case dict:find({local,Name,Arity}, Dict) of
{ok, Cs} ->
LF = {value,fun(I, J) -> code_handler(I, J, Dict, File) end},
case erl_eval:match_clause(Cs, Args,erl_eval:new_bindings(),LF) of
{Body, Bs} ->
eval_exprs(Body, Bs, LF, none, none);
nomatch ->
erlang:error({function_clause,[{local,Name,Args}]})
end;
error ->
case dict:find({remote,{Name,Arity}}, Dict) of
{ok, Mod} ->
%% io:format("Calling:~p~n",[{Mod,Name,Args}]),
apply(Mod, Name, Args);
error ->
io:format("Script does not export ~w/~w\n", [Name,Arity]),
my_halt(127)
end
end.
eval_exprs([E], Bs0, Lf, Ef, _RBs) ->
RBs1 = value,
erl_eval:expr(E, Bs0, Lf, Ef, RBs1);
eval_exprs([E|Es], Bs0, Lf, Ef, RBs) ->
RBs1 = none,
{value,_V,Bs} = erl_eval:expr(E, Bs0, Lf, Ef, RBs1),
eval_exprs(Es, Bs, Lf, Ef, RBs).
format_exception(Class, Reason) ->
PF = fun(Term, I) ->
io_lib:format("~." ++ integer_to_list(I) ++ "P", [Term, 50])
end,
StackTrace = erlang:get_stacktrace(),
StackFun = fun(M, _F, _A) -> (M =:= erl_eval) or (M =:= ?MODULE) end,
lib:format_exception(1, Class, Reason, StackTrace, StackFun, PF).
fatal(Str) ->
throw(Str).
my_halt(Reason) ->
case process_info(group_leader(), status) of
{_,waiting} ->
%% Now all output data is down in the driver.
%% Give the driver some extra time before halting.
receive after 1 -> ok end,
halt(Reason);
_ ->
%% Probably still processing I/O requests.
erlang:yield(),
my_halt(Reason)
end.
hidden_apply(App, M, F, Args) ->
try
apply(fun() -> M end(), F, Args)
catch
error:undef ->
case erlang:get_stacktrace() of
[{M,F,Args} | _] ->
Arity = length(Args),
Text = io_lib:format("Call to ~w:~w/~w in application ~w failed.\n",
[M, F, Arity, App]),
fatal(Text);
Stk ->
erlang:raise(error, undef, Stk)
end
end.
