%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1996-2011. 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(io).
-export([put_chars/1,put_chars/2,nl/0,nl/1,
get_chars/2,get_chars/3,get_line/1,get_line/2,
get_password/0, get_password/1,
setopts/1, setopts/2, getopts/0, getopts/1]).
-export([write/1,write/2,read/1,read/2,read/3]).
-export([columns/0,columns/1,rows/0,rows/1]).
-export([fwrite/1,fwrite/2,fwrite/3,fread/2,fread/3,
format/1,format/2,format/3]).
-export([scan_erl_exprs/1,scan_erl_exprs/2,scan_erl_exprs/3,
scan_erl_form/1,scan_erl_form/2,scan_erl_form/3,
parse_erl_exprs/1,parse_erl_exprs/2,parse_erl_exprs/3,
parse_erl_form/1,parse_erl_form/2,parse_erl_form/3]).
-export([request/1,request/2,requests/1,requests/2]).
-export_type([device/0, format/0]).
%%-------------------------------------------------------------------------
-type device() :: atom() | pid().
-type prompt() :: atom() | string().
-type error_description() :: term(). % Whatever the io-server sends.
-type request_error() :: {'error',error_description()}.
%% XXX: Some uses of line() in this file may need to read erl_scan:location()
-type line() :: pos_integer().
%%-------------------------------------------------------------------------
%%
%% User interface.
%%
%% Writing and reading characters.
to_tuple(T) when is_tuple(T) -> T;
to_tuple(T) -> {T}.
o_request(Io, Request, Func) ->
case request(Io, Request) of
{error, Reason} ->
[_Name | Args] = tuple_to_list(to_tuple(Request)),
{'EXIT',{get_stacktrace,[_Current|Mfas]}} = (catch erlang:error(get_stacktrace)),
erlang:raise(error, conv_reason(Func, Reason), [{io, Func, [Io | Args]}|Mfas]);
Other ->
Other
end.
%% Put chars takes mixed *unicode* list from R13 onwards.
-spec put_chars(iodata()) -> 'ok'.
put_chars(Chars) ->
put_chars(default_output(), Chars).
-spec put_chars(device(), iodata()) -> 'ok'.
put_chars(Io, Chars) ->
o_request(Io, {put_chars,unicode,Chars}, put_chars).
-spec nl() -> 'ok'.
nl() ->
nl(default_output()).
-spec nl(device()) -> 'ok'.
nl(Io) ->
% o_request(Io, {put_chars,io_lib:nl()}).
o_request(Io, nl, nl).
-spec columns() -> {'ok', pos_integer()} | {'error', 'enotsup'}.
columns() ->
columns(default_output()).
-spec columns(device()) -> {'ok', pos_integer()} | {'error', 'enotsup'}.
columns(Io) ->
case request(Io, {get_geometry,columns}) of
N when is_integer(N), N > 0 ->
{ok,N};
_ ->
{error,enotsup}
end.
-spec rows() -> {'ok', pos_integer()} | {'error', 'enotsup'}.
rows() ->
rows(default_output()).
-spec rows(device()) -> {'ok', pos_integer()} | {'error', 'enotsup'}.
rows(Io) ->
case request(Io,{get_geometry,rows}) of
N when is_integer(N), N > 0 ->
{ok,N};
_ ->
{error,enotsup}
end.
-spec get_chars(prompt(), non_neg_integer()) -> iodata() | 'eof'.
get_chars(Prompt, N) ->
get_chars(default_input(), Prompt, N).
-spec get_chars(device(), prompt(), non_neg_integer()) -> iodata() | 'eof'.
get_chars(Io, Prompt, N) when is_integer(N), N >= 0 ->
request(Io, {get_chars,unicode,Prompt,N}).
-spec get_line(prompt()) -> iodata() | 'eof' | {'error', term()}.
get_line(Prompt) ->
get_line(default_input(), Prompt).
-spec get_line(device(), prompt()) -> iodata() | 'eof' | {'error', term()}.
get_line(Io, Prompt) ->
request(Io, {get_line,unicode,Prompt}).
get_password() ->
get_password(default_input()).
get_password(Io) ->
request(Io, {get_password,unicode}).
-type encoding() :: 'latin1' | 'unicode' | 'utf8' | 'utf16' | 'utf32'
| {'utf16', 'big' | 'little'} | {'utf32','big' | 'little'}.
-type expand_fun() :: fun((term()) -> {'yes'|'no', string(), [string(), ...]}).
-type opt_pair() :: {'binary', boolean()}
| {'echo', boolean()}
| {'expand_fun', expand_fun()}
| {'encoding', encoding()}.
-spec getopts() -> [opt_pair()].
getopts() ->
getopts(default_input()).
-spec getopts(device()) -> [opt_pair()].
getopts(Io) ->
request(Io, getopts).
-type setopt() :: 'binary' | 'list' | opt_pair().
-spec setopts([setopt()]) -> 'ok' | {'error', term()}.
setopts(Opts) ->
setopts(default_input(), Opts).
-spec setopts(device(), [setopt()]) -> 'ok' | {'error', term()}.
setopts(Io, Opts) ->
request(Io, {setopts, Opts}).
%% Writing and reading Erlang terms.
-spec write(term()) -> 'ok'.
write(Term) ->
write(default_output(), Term).
-spec write(device(), term()) -> 'ok'.
write(Io, Term) ->
o_request(Io, {write,Term}, write).
-spec read(prompt()) ->
{'ok', term()} | 'eof' | {'error', erl_scan:error_info()}.
% Read does not use get_until as erl_scan does not work with unicode
% XXX:PaN fixme?
read(Prompt) ->
read(default_input(), Prompt).
-spec read(device(), prompt()) ->
{'ok', term()} | 'eof' | {'error', erl_scan:error_info()}.
read(Io, Prompt) ->
case request(Io, {get_until,unicode,Prompt,erl_scan,tokens,[1]}) of
{ok,Toks,_EndLine} ->
erl_parse:parse_term(Toks);
% {error, Reason} when atom(Reason) ->
% erlang:error(conv_reason(read, Reason), [Io, Prompt]);
{error,E,_EndLine} ->
{error,E};
{eof,_EndLine} ->
eof;
Other ->
Other
end.
-spec read(device(), prompt(), line()) ->
{'ok', term(), line()} | {'eof', line()} |
{'error', erl_scan:error_info(), line()}.
read(Io, Prompt, StartLine) when is_integer(StartLine) ->
case request(Io, {get_until,unicode,Prompt,erl_scan,tokens,[StartLine]}) of
{ok,Toks,EndLine} ->
case erl_parse:parse_term(Toks) of
{ok,Term} -> {ok,Term,EndLine};
{error,ErrorInfo} -> {error,ErrorInfo,EndLine}
end;
{error,_E,_EndLine} = Error ->
Error;
{eof,_EndLine} = Eof ->
Eof;
Other ->
Other
end.
%% Formatted writing and reading.
conv_reason(_, arguments) -> badarg;
conv_reason(_, terminated) -> terminated;
conv_reason(_, {no_translation,_,_}) -> no_translation;
conv_reason(_, _Reason) -> badarg.
-type format() :: atom() | string() | binary().
-spec fwrite(format()) -> 'ok'.
fwrite(Format) ->
format(Format).
-spec fwrite(format(), [term()]) -> 'ok'.
fwrite(Format, Args) ->
format(Format, Args).
-spec fwrite(device(), format(), [term()]) -> 'ok'.
fwrite(Io, Format, Args) ->
format(Io, Format, Args).
-spec fread(prompt(), format()) -> {'ok', [term()]} | 'eof' | {'error',term()}.
fread(Prompt, Format) ->
fread(default_input(), Prompt, Format).
-spec fread(device(), prompt(), format()) ->
{'ok', [term()]} | 'eof' | {'error',term()}.
fread(Io, Prompt, Format) ->
case request(Io, {fread,Prompt,Format}) of
% {error, Reason} when atom(Reason) ->
% erlang:error(conv_reason(fread, Reason), [Io, Prompt, Format]);
Other ->
Other
end.
-spec format(format()) -> 'ok'.
format(Format) ->
format(Format, []).
-spec format(format(), [term()]) -> 'ok'.
format(Format, Args) ->
format(default_output(), Format, Args).
-spec format(device(), format(), [term()]) -> 'ok'.
format(Io, Format, Args) ->
o_request(Io, {format,Format,Args}, format).
%% Scanning Erlang code.
-spec scan_erl_exprs(prompt()) -> erl_scan:tokens_result() | request_error().
scan_erl_exprs(Prompt) ->
scan_erl_exprs(default_input(), Prompt, 1).
-spec scan_erl_exprs(device(), prompt()) -> erl_scan:tokens_result() | request_error().
scan_erl_exprs(Io, Prompt) ->
scan_erl_exprs(Io, Prompt, 1).
-spec scan_erl_exprs(device(), prompt(), line()) -> erl_scan:tokens_result() | request_error().
scan_erl_exprs(Io, Prompt, Pos0) ->
request(Io, {get_until,unicode,Prompt,erl_scan,tokens,[Pos0]}).
-spec scan_erl_form(prompt()) -> erl_scan:tokens_result() | request_error().
scan_erl_form(Prompt) ->
scan_erl_form(default_input(), Prompt, 1).
-spec scan_erl_form(device(), prompt()) -> erl_scan:tokens_result() | request_error().
scan_erl_form(Io, Prompt) ->
scan_erl_form(Io, Prompt, 1).
-spec scan_erl_form(device(), prompt(), line()) -> erl_scan:tokens_result() | request_error().
scan_erl_form(Io, Prompt, Pos0) ->
request(Io, {get_until,unicode,Prompt,erl_scan,tokens,[Pos0]}).
%% Parsing Erlang code.
-type erl_parse_expr_list() :: [_]. %% XXX: should be imported from erl_parse
-type parse_ret() :: {'ok', erl_parse_expr_list(), line()}
| {'eof', line()}
| {'error', erl_scan:error_info(), line()}
| request_error().
-spec parse_erl_exprs(prompt()) -> parse_ret().
parse_erl_exprs(Prompt) ->
parse_erl_exprs(default_input(), Prompt, 1).
-spec parse_erl_exprs(device(), prompt()) -> parse_ret().
parse_erl_exprs(Io, Prompt) ->
parse_erl_exprs(Io, Prompt, 1).
-spec parse_erl_exprs(device(), prompt(), line()) -> parse_ret().
parse_erl_exprs(Io, Prompt, Pos0) ->
case request(Io, {get_until,unicode,Prompt,erl_scan,tokens,[Pos0]}) of
{ok,Toks,EndPos} ->
case erl_parse:parse_exprs(Toks) of
{ok,Exprs} -> {ok,Exprs,EndPos};
{error,E} -> {error,E,EndPos}
end;
Other ->
Other
end.
-type erl_parse_absform() :: _. %% XXX: should be imported from erl_parse
-type parse_form_ret() :: {'ok', erl_parse_absform(), line()}
| {'eof', line()}
| {'error', erl_scan:error_info(), line()}
| request_error().
-spec parse_erl_form(prompt()) -> parse_form_ret().
parse_erl_form(Prompt) ->
parse_erl_form(default_input(), Prompt, 1).
-spec parse_erl_form(device(), prompt()) -> parse_form_ret().
parse_erl_form(Io, Prompt) ->
parse_erl_form(Io, Prompt, 1).
-spec parse_erl_form(device(), prompt(), line()) -> parse_form_ret().
parse_erl_form(Io, Prompt, Pos0) ->
case request(Io, {get_until,unicode,Prompt,erl_scan,tokens,[Pos0]}) of
{ok,Toks,EndPos} ->
case erl_parse:parse_form(Toks) of
{ok,Exprs} -> {ok,Exprs,EndPos};
{error,E} -> {error,E,EndPos}
end;
Other ->
Other
end.
%% Miscellaneous functions.
request(Request) ->
request(default_output(), Request).
request(standard_io, Request) ->
request(group_leader(), Request);
request(Pid, Request) when is_pid(Pid) ->
execute_request(Pid, io_request(Pid, Request));
request(Name, Request) when is_atom(Name) ->
case whereis(Name) of
undefined ->
{error, arguments};
Pid ->
request(Pid, Request)
end.
execute_request(Pid, {Convert,Converted}) ->
Mref = erlang:monitor(process, Pid),
Pid ! {io_request,self(),Pid,Converted},
if
Convert ->
convert_binaries(wait_io_mon_reply(Pid, Mref));
true ->
wait_io_mon_reply(Pid, Mref)
end.
requests(Requests) -> %Requests as atomic action
requests(default_output(), Requests).
requests(standard_io, Requests) -> %Requests as atomic action
requests(group_leader(), Requests);
requests(Pid, Requests) when is_pid(Pid) ->
{Convert, Converted} = io_requests(Pid, Requests),
execute_request(Pid,{Convert,{requests,Converted}});
requests(Name, Requests) when is_atom(Name) ->
case whereis(Name) of
undefined ->
{error, arguments};
Pid ->
requests(Pid, Requests)
end.
default_input() ->
group_leader().
default_output() ->
group_leader().
wait_io_mon_reply(From, Mref) ->
receive
{io_reply, From, Reply} ->
erlang:demonitor(Mref),
receive
{'DOWN', Mref, _, _, _} -> true
after 0 -> true
end,
Reply;
{'EXIT', From, _What} ->
receive
{'DOWN', Mref, _, _, _} -> true
after 0 -> true
end,
{error,terminated};
{'DOWN', Mref, _, _, _} ->
receive
{'EXIT', From, _What} -> true
after 0 -> true
end,
{error,terminated}
end.
%% io_requests(Requests)
%% Transform requests into correct i/o server messages. Only handle the
%% one we KNOW must be changed, others, including incorrect ones, are
%% passed straight through. Perform a flatten on the request list.
io_requests(Pid, Rs) ->
io_requests(Pid, Rs, [], []).
io_requests(Pid, [{requests,Rs1}|Rs], Cont, Tail) ->
io_requests(Pid, Rs1, [Rs|Cont], Tail);
io_requests(Pid, [R], [], _Tail) ->
{Conv,Request} = io_request(Pid, R),
{Conv,[Request]};
io_requests(Pid, [R|Rs], Cont, Tail) ->
{_,Request} = io_request(Pid, R),
{Conv,Requests} = io_requests(Pid, Rs, Cont, Tail),
{Conv,[Request|Requests]};
io_requests(Pid, [], [Rs|Cont], Tail) ->
io_requests(Pid, Rs, Cont, Tail);
io_requests(_Pid, [], [], _Tail) ->
{false,[]}.
bc_req(Pid,{Op,Enc,Param},MaybeConvert) ->
case net_kernel:dflag_unicode_io(Pid) of
true ->
{false,{Op,Enc,Param}};
false ->
{MaybeConvert,{Op,Param}}
end;
bc_req(Pid,{Op,Enc,P,F},MaybeConvert) ->
case net_kernel:dflag_unicode_io(Pid) of
true ->
{false,{Op,Enc,P,F}};
false ->
{MaybeConvert,{Op,P,F}}
end;
bc_req(Pid, {Op,Enc,M,F,A},MaybeConvert) ->
case net_kernel:dflag_unicode_io(Pid) of
true ->
{false,{Op,Enc,M,F,A}};
false ->
{MaybeConvert,{Op,M,F,A}}
end;
bc_req(Pid, {Op,Enc,P,M,F,A},MaybeConvert) ->
case net_kernel:dflag_unicode_io(Pid) of
true ->
{false,{Op,Enc,P,M,F,A}};
false ->
{MaybeConvert,{Op,P,M,F,A}}
end;
bc_req(Pid,{Op,Enc},MaybeConvert) ->
case net_kernel:dflag_unicode_io(Pid) of
true ->
{false,{Op, Enc}};
false ->
{MaybeConvert,Op}
end.
io_request(Pid, {write,Term}) ->
bc_req(Pid,{put_chars,unicode,io_lib,write,[Term]},false);
io_request(Pid, {format,Format,Args}) ->
bc_req(Pid,{put_chars,unicode,io_lib,format,[Format,Args]},false);
io_request(Pid, {fwrite,Format,Args}) ->
bc_req(Pid,{put_chars,unicode,io_lib,fwrite,[Format,Args]},false);
io_request(Pid, nl) ->
bc_req(Pid,{put_chars,unicode,io_lib:nl()},false);
io_request(Pid, {put_chars,Enc,Chars}=Request0)
when is_list(Chars), node(Pid) =:= node() ->
%% Convert to binary data if the I/O server is guaranteed to be new
Request =
case catch unicode:characters_to_binary(Chars,Enc) of
Binary when is_binary(Binary) ->
{put_chars,Enc,Binary};
_ ->
Request0
end,
{false,Request};
io_request(Pid, {put_chars,Enc,Chars}=Request0)
when is_list(Chars) ->
case net_kernel:dflag_unicode_io(Pid) of
true ->
case catch unicode:characters_to_binary(Chars,Enc,unicode) of
Binary when is_binary(Binary) ->
{false,{put_chars,unicode,Binary}};
_ ->
{false,Request0}
end;
false ->
%% Convert back to old style put_chars message...
case catch unicode:characters_to_binary(Chars,Enc,latin1) of
Binary when is_binary(Binary) ->
{false,{put_chars,Binary}};
_ ->
{false,{put_chars,Chars}}
end
end;
io_request(Pid, {fread,Prompt,Format}) ->
bc_req(Pid,{get_until,unicode,Prompt,io_lib,fread,[Format]},true);
io_request(Pid, {get_until,Enc,Prompt,M,F,A}) ->
bc_req(Pid,{get_until,Enc,Prompt,M,F,A},true);
io_request(Pid, {get_chars,Enc,Prompt,N}) ->
bc_req(Pid,{get_chars,Enc,Prompt,N},true);
io_request(Pid, {get_line,Enc,Prompt}) ->
bc_req(Pid,{get_line,Enc,Prompt},true);
io_request(Pid, {get_password,Enc}) ->
bc_req(Pid,{get_password, Enc},true);
io_request(_Pid, R) -> %Pass this straight through
{false,R}.
convert_binaries(Bin) when is_binary(Bin) ->
unicode:characters_to_binary(Bin,latin1,unicode);
convert_binaries(Else) ->
Else.
