%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1996-2018. 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(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,read/4]).
-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_exprs/4,
scan_erl_form/1,scan_erl_form/2,scan_erl_form/3,scan_erl_form/4,
parse_erl_exprs/1,parse_erl_exprs/2,parse_erl_exprs/3,
parse_erl_exprs/4,parse_erl_form/1,parse_erl_form/2,
parse_erl_form/3,parse_erl_form/4]).
-export([request/1,request/2,requests/1,requests/2]).
%% Implemented in native code
-export([printable_range/0]).
-export_type([device/0, format/0, server_no_data/0]).
%%-------------------------------------------------------------------------
-type device() :: atom() | pid().
-type prompt() :: atom() | unicode:chardata().
%% ErrorDescription is whatever the I/O-server sends.
-type server_no_data() :: {'error', ErrorDescription :: term()} | 'eof'.
-type location() :: erl_anno:location().
%%-------------------------------------------------------------------------
%%
%% 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.
%% Request what the user considers printable characters
-spec printable_range() -> 'unicode' | 'latin1'.
printable_range() ->
erlang:nif_error(undefined).
%% Put chars takes mixed *unicode* list from R13 onwards.
-spec put_chars(CharData) -> 'ok' when
CharData :: unicode:chardata().
put_chars(Chars) ->
put_chars(default_output(), Chars).
-spec put_chars(IoDevice, CharData) -> 'ok' when
IoDevice :: device(),
CharData :: unicode:chardata().
put_chars(Io, Chars) ->
put_chars(Io, unicode, Chars).
%% This function is here to make the erlang:raise in o_request actually raise to
%% a valid function.
-spec put_chars(IoDevice, Encoding, CharData) -> 'ok' when
IoDevice :: device(),
Encoding :: unicode,
CharData :: unicode:chardata().
put_chars(Io, Encoding, Chars) ->
o_request(Io, {put_chars,Encoding,Chars}, put_chars).
-spec nl() -> 'ok'.
nl() ->
nl(default_output()).
-spec nl(IoDevice) -> 'ok' when
IoDevice :: device().
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(IoDevice) -> {'ok', pos_integer()} | {'error', 'enotsup'} when
IoDevice :: device().
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(IoDevice) -> {'ok', pos_integer()} | {'error', 'enotsup'} when
IoDevice :: device().
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, Count) -> Data | server_no_data() when
Prompt :: prompt(),
Count :: non_neg_integer(),
Data :: string() | unicode:unicode_binary().
get_chars(Prompt, N) ->
get_chars(default_input(), Prompt, N).
-spec get_chars(IoDevice, Prompt, Count) -> Data | server_no_data() when
IoDevice :: device(),
Prompt :: prompt(),
Count :: non_neg_integer(),
Data :: string() | unicode:unicode_binary().
get_chars(Io, Prompt, N) when is_integer(N), N >= 0 ->
request(Io, {get_chars,unicode,Prompt,N}).
-spec get_line(Prompt) -> Data | server_no_data() when
Prompt :: prompt(),
Data :: string() | unicode:unicode_binary().
get_line(Prompt) ->
get_line(default_input(), Prompt).
-spec get_line(IoDevice, Prompt) -> Data | server_no_data() when
IoDevice :: device(),
Prompt :: prompt(),
Data :: string() | unicode:unicode_binary().
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()] | {'error', Reason} when
Reason :: term().
getopts() ->
getopts(default_input()).
-spec getopts(IoDevice) -> [opt_pair()] | {'error', Reason} when
IoDevice :: device(),
Reason :: term().
getopts(Io) ->
request(Io, getopts).
-type setopt() :: 'binary' | 'list' | opt_pair().
-spec setopts(Opts) -> 'ok' | {'error', Reason} when
Opts :: [setopt()],
Reason :: term().
setopts(Opts) ->
setopts(default_input(), Opts).
-spec setopts(IoDevice, Opts) -> 'ok' | {'error', Reason} when
IoDevice :: device(),
Opts :: [setopt()],
Reason :: term().
setopts(Io, Opts) ->
request(Io, {setopts, Opts}).
%% Writing and reading Erlang terms.
-spec write(Term) -> 'ok' when
Term :: term().
write(Term) ->
write(default_output(), Term).
-spec write(IoDevice, Term) -> 'ok' when
IoDevice :: device(),
Term :: term().
write(Io, Term) ->
o_request(Io, {write,Term}, write).
-spec read(Prompt) -> Result when
Prompt :: prompt(),
Result :: {'ok', Term :: term()}
| server_no_data()
| {'error', ErrorInfo},
ErrorInfo :: erl_scan:error_info() | erl_parse:error_info().
read(Prompt) ->
read(default_input(), Prompt).
-spec read(IoDevice, Prompt) -> Result when
IoDevice :: device(),
Prompt :: prompt(),
Result :: {'ok', Term :: term()}
| server_no_data()
| {'error', ErrorInfo},
ErrorInfo :: erl_scan:error_info() | erl_parse: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(IoDevice, Prompt, StartLocation) -> Result when
IoDevice :: device(),
Prompt :: prompt(),
StartLocation :: location(),
Result :: {'ok', Term :: term(), EndLocation :: location()}
| {'eof', EndLocation :: location()}
| server_no_data()
| {'error', ErrorInfo, ErrorLocation :: location()},
ErrorInfo :: erl_scan:error_info() | erl_parse:error_info().
read(Io, Prompt, Pos0) ->
read(Io, Prompt, Pos0, []).
-spec read(IoDevice, Prompt, StartLocation, Options) -> Result when
IoDevice :: device(),
Prompt :: prompt(),
StartLocation :: location(),
Options :: erl_scan:options(),
Result :: {'ok', Term :: term(), EndLocation :: location()}
| {'eof', EndLocation :: location()}
| server_no_data()
| {'error', ErrorInfo, ErrorLocation :: location()},
ErrorInfo :: erl_scan:error_info() | erl_parse:error_info().
read(Io, Prompt, Pos0, Options) ->
Args = [Pos0,Options],
case request(Io, {get_until,unicode,Prompt,erl_scan,tokens,Args}) of
{ok,Toks,EndLocation} ->
case erl_parse:parse_term(Toks) of
{ok,Term} -> {ok,Term,EndLocation};
{error,ErrorInfo} -> {error,ErrorInfo,EndLocation}
end;
{error,_E,_EndLocation} = Error ->
Error;
{eof,_EndLocation} = 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' when
Format :: format().
fwrite(Format) ->
format(Format).
-spec fwrite(Format, Data) -> 'ok' when
Format :: format(),
Data :: [term()].
fwrite(Format, Args) ->
format(Format, Args).
-spec fwrite(IoDevice, Format, Data) -> 'ok' when
IoDevice :: device(),
Format :: format(),
Data :: [term()].
fwrite(Io, Format, Args) ->
format(Io, Format, Args).
-spec fread(Prompt, Format) -> Result when
Prompt :: prompt(),
Format :: format(),
Result :: {'ok', Terms :: [term()]} | 'eof' | {'error', What :: term()}.
fread(Prompt, Format) ->
fread(default_input(), Prompt, Format).
-spec fread(IoDevice, Prompt, Format) -> Result when
IoDevice :: device(),
Prompt :: prompt(),
Format :: format(),
Result :: {'ok', Terms :: [term()]}
| {'error', {'fread', FreadError :: io_lib:fread_error()}}
| server_no_data().
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' when
Format :: format().
format(Format) ->
format(Format, []).
-spec format(Format, Data) -> 'ok' when
Format :: format(),
Data :: [term()].
format(Format, Args) ->
format(default_output(), Format, Args).
-spec format(IoDevice, Format, Data) -> 'ok' when
IoDevice :: device(),
Format :: format(),
Data :: [term()].
format(Io, Format, Args) ->
o_request(Io, {format,Format,Args}, format).
%% Scanning Erlang code.
-spec scan_erl_exprs(Prompt) -> Result when
Prompt :: prompt(),
Result :: erl_scan:tokens_result() | server_no_data().
scan_erl_exprs(Prompt) ->
scan_erl_exprs(default_input(), Prompt, 1).
-spec scan_erl_exprs(Device, Prompt) -> Result when
Device :: device(),
Prompt :: prompt(),
Result :: erl_scan:tokens_result() | server_no_data().
scan_erl_exprs(Io, Prompt) ->
scan_erl_exprs(Io, Prompt, 1).
-spec scan_erl_exprs(Device, Prompt, StartLocation) -> Result when
Device :: device(),
Prompt :: prompt(),
StartLocation :: location(),
Result :: erl_scan:tokens_result() | server_no_data().
scan_erl_exprs(Io, Prompt, Pos0) ->
scan_erl_exprs(Io, Prompt, Pos0, []).
-spec scan_erl_exprs(Device, Prompt, StartLocation, Options) -> Result when
Device :: device(),
Prompt :: prompt(),
StartLocation :: location(),
Options :: erl_scan:options(),
Result :: erl_scan:tokens_result() | server_no_data().
scan_erl_exprs(Io, Prompt, Pos0, Options) ->
request(Io, {get_until,unicode,Prompt,erl_scan,tokens,[Pos0,Options]}).
-spec scan_erl_form(Prompt) -> Result when
Prompt :: prompt(),
Result :: erl_scan:tokens_result() | server_no_data().
scan_erl_form(Prompt) ->
scan_erl_form(default_input(), Prompt, 1).
-spec scan_erl_form(IoDevice, Prompt) -> Result when
IoDevice :: device(),
Prompt :: prompt(),
Result :: erl_scan:tokens_result() | server_no_data().
scan_erl_form(Io, Prompt) ->
scan_erl_form(Io, Prompt, 1).
-spec scan_erl_form(IoDevice, Prompt, StartLocation) -> Result when
IoDevice :: device(),
Prompt :: prompt(),
StartLocation :: location(),
Result :: erl_scan:tokens_result() | server_no_data().
scan_erl_form(Io, Prompt, Pos0) ->
scan_erl_form(Io, Prompt, Pos0, []).
-spec scan_erl_form(IoDevice, Prompt, StartLocation, Options) -> Result when
IoDevice :: device(),
Prompt :: prompt(),
StartLocation :: location(),
Options :: erl_scan:options(),
Result :: erl_scan:tokens_result() | server_no_data().
scan_erl_form(Io, Prompt, Pos0, Options) ->
request(Io, {get_until,unicode,Prompt,erl_scan,tokens,[Pos0,Options]}).
%% Parsing Erlang code.
-type parse_ret() :: {'ok',
ExprList :: [erl_parse:abstract_expr()],
EndLocation :: location()}
| {'eof', EndLocation :: location()}
| {'error',
ErrorInfo :: erl_scan:error_info()
| erl_parse:error_info(),
ErrorLocation :: location()}
| server_no_data().
-spec parse_erl_exprs(Prompt) -> Result when
Prompt :: prompt(),
Result :: parse_ret().
parse_erl_exprs(Prompt) ->
parse_erl_exprs(default_input(), Prompt, 1).
-spec parse_erl_exprs(IoDevice, Prompt) -> Result when
IoDevice :: device(),
Prompt :: prompt(),
Result :: parse_ret().
parse_erl_exprs(Io, Prompt) ->
parse_erl_exprs(Io, Prompt, 1).
-spec parse_erl_exprs(IoDevice, Prompt, StartLocation) -> Result when
IoDevice :: device(),
Prompt :: prompt(),
StartLocation :: location(),
Result :: parse_ret().
parse_erl_exprs(Io, Prompt, Pos0) ->
parse_erl_exprs(Io, Prompt, Pos0, []).
-spec parse_erl_exprs(IoDevice, Prompt, StartLocation, Options) -> Result when
IoDevice :: device(),
Prompt :: prompt(),
StartLocation :: location(),
Options :: erl_scan:options(),
Result :: parse_ret().
parse_erl_exprs(Io, Prompt, Pos0, Options) ->
case request(Io, {get_until,unicode,Prompt,erl_scan,tokens,[Pos0,Options]}) 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 parse_form_ret() :: {'ok',
AbsForm :: erl_parse:abstract_form(),
EndLocation :: location()}
| {'eof', EndLocation :: location()}
| {'error',
ErrorInfo :: erl_scan:error_info()
| erl_parse:error_info(),
ErrorLocation :: location()}
| server_no_data().
-spec parse_erl_form(Prompt) -> Result when
Prompt :: prompt(),
Result :: parse_form_ret().
parse_erl_form(Prompt) ->
parse_erl_form(default_input(), Prompt, 1).
-spec parse_erl_form(IoDevice, Prompt) -> Result when
IoDevice :: device(),
Prompt :: prompt(),
Result :: parse_form_ret().
parse_erl_form(Io, Prompt) ->
parse_erl_form(Io, Prompt, 1).
-spec parse_erl_form(IoDevice, Prompt, StartLocation) -> Result when
IoDevice :: device(),
Prompt :: prompt(),
StartLocation :: location(),
Result :: parse_form_ret().
parse_erl_form(Io, Prompt, Pos0) ->
parse_erl_form(Io, Prompt, Pos0, []).
-spec parse_erl_form(IoDevice, Prompt, StartLocation, Options) -> Result when
IoDevice :: device(),
Prompt :: prompt(),
StartLocation :: location(),
Options :: erl_scan:options(),
Result :: parse_form_ret().
parse_erl_form(Io, Prompt, Pos0, Options) ->
Args = [Pos0, Options],
case request(Io, {get_until,unicode,Prompt,erl_scan,tokens,Args}) 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(),Mref,Converted},
receive
{io_reply, Mref, Reply} ->
erlang:demonitor(Mref, [flush]),
if
Convert ->
convert_binaries(Reply);
true ->
Reply
end;
{'DOWN', Mref, _, _, _} ->
receive
{'EXIT', Pid, _What} -> true
after 0 -> true
end,
{error,terminated}
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().
%% 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, Req0, MaybeConvert) ->
case net_kernel:dflag_unicode_io(Pid) of
true ->
%% The most common case. A modern i/o server.
{false,Req0};
false ->
%% Backward compatibility only. Unlikely to ever happen.
case tuple_to_list(Req0) of
[Op,_Enc] ->
{MaybeConvert,Op};
[Op,_Enc|T] ->
Req = list_to_tuple([Op|T]),
{MaybeConvert,Req}
end
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.
