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authorErlang/OTP <[email protected]>2009-11-20 14:54:40 +0000
committerErlang/OTP <[email protected]>2009-11-20 14:54:40 +0000
commit84adefa331c4159d432d22840663c38f155cd4c1 (patch)
treebff9a9c66adda4df2106dfd0e5c053ab182a12bd /lib/stdlib/src/io.erl
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The R13B03 release.OTP_R13B03
Diffstat (limited to 'lib/stdlib/src/io.erl')
-rw-r--r--lib/stdlib/src/io.erl578
1 files changed, 578 insertions, 0 deletions
diff --git a/lib/stdlib/src/io.erl b/lib/stdlib/src/io.erl
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+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 1996-2009. 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]).
+
+
+%%-------------------------------------------------------------------------
+
+-type device() :: atom() | pid().
+-type prompt() :: atom() | string().
+
+%% 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}.
+
+%% Problem: the variables Other, Name and Args may collide with surrounding
+%% ones.
+%% Give extra args to macro, being the variables to use.
+-define(O_REQUEST(Io, Request),
+ case request(Io, Request) of
+ {error, Reason} ->
+ [Name | Args] = tuple_to_list(to_tuple(Request)),
+ erlang:error(conv_reason(Name, Reason), [Name, Io | Args]);
+ Other ->
+ Other
+ end).
+
+o_request(Io, Request, Func) ->
+ case request(Io, Request) of
+ {error, Reason} ->
+ [_Name | Args] = tuple_to_list(to_tuple(Request)),
+ {'EXIT',{undef,[_Current|Mfas]}} = (catch erlang:error(undef)),
+ MFA = {io, Func, [Io | Args]},
+ exit({conv_reason(Func, Reason),[MFA|Mfas]});
+% erlang:error(conv_reason(Name, Reason), [Name, Io | Args]);
+ 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().
+
+scan_erl_exprs(Prompt) ->
+ scan_erl_exprs(default_input(), Prompt, 1).
+
+-spec scan_erl_exprs(device(), prompt()) -> erl_scan:tokens_result().
+
+scan_erl_exprs(Io, Prompt) ->
+ scan_erl_exprs(Io, Prompt, 1).
+
+-spec scan_erl_exprs(device(), prompt(), line()) -> erl_scan:tokens_result().
+
+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().
+
+scan_erl_form(Prompt) ->
+ scan_erl_form(default_input(), Prompt, 1).
+
+-spec scan_erl_form(device(), prompt()) -> erl_scan:tokens_result().
+
+scan_erl_form(Io, Prompt) ->
+ scan_erl_form(Io, Prompt, 1).
+
+-spec scan_erl_form(device(), prompt(), line()) -> erl_scan:tokens_result().
+
+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()}.
+
+-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()}.
+
+-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.