%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2000-2013. 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(file_io_server).
%% A simple file server for io to one file instance per server instance.
-export([format_error/1]).
-export([start/3, start_link/3]).
-export([count_and_find/3]).
-record(state, {handle,owner,mref,buf,read_mode,unic}).
-define(PRIM_FILE, prim_file).
-define(READ_SIZE_LIST, 128).
-define(READ_SIZE_BINARY, (8*1024)).
-define(eat_message(M, T), receive M -> M after T -> timeout end).
%%%-----------------------------------------------------------------
%%% Exported functions
format_error({_Line, ?MODULE, Reason}) ->
io_lib:format("~w", [Reason]);
format_error({_Line, Mod, Reason}) ->
Mod:format_error(Reason);
format_error(invalid_unicode) ->
io_lib:format("cannot translate from UTF-8", []);
format_error(ErrorId) ->
erl_posix_msg:message(ErrorId).
start(Owner, FileName, ModeList)
when is_pid(Owner), (is_list(FileName) orelse is_binary(FileName)), is_list(ModeList) ->
do_start(spawn, Owner, FileName, ModeList).
start_link(Owner, FileName, ModeList)
when is_pid(Owner), (is_list(FileName) orelse is_binary(FileName)), is_list(ModeList) ->
do_start(spawn_link, Owner, FileName, ModeList).
%%%-----------------------------------------------------------------
%%% Server starter, dispatcher and helpers
do_start(Spawn, Owner, FileName, ModeList) ->
Self = self(),
Ref = make_ref(),
Utag = erlang:dt_spread_tag(true),
Pid =
erlang:Spawn(
fun() ->
erlang:dt_restore_tag(Utag),
%% process_flag(trap_exit, true),
case parse_options(ModeList) of
{ReadMode, UnicodeMode, Opts} ->
case ?PRIM_FILE:open(FileName, Opts) of
{error, Reason} = Error ->
Self ! {Ref, Error},
exit(Reason);
{ok, Handle} ->
%% XXX must I handle R6 nodes here?
M = erlang:monitor(process, Owner),
Self ! {Ref, ok},
server_loop(
#state{handle = Handle,
owner = Owner,
mref = M,
buf = <<>>,
read_mode = ReadMode,
unic = UnicodeMode})
end;
{error,Reason1} = Error1 ->
Self ! {Ref, Error1},
exit(Reason1)
end
end),
erlang:dt_restore_tag(Utag),
Mref = erlang:monitor(process, Pid),
receive
{Ref, {error, _Reason} = Error} ->
erlang:demonitor(Mref, [flush]),
Error;
{Ref, ok} ->
erlang:demonitor(Mref),
receive
{'DOWN', Mref, _, _, Reason} ->
{error, Reason}
after 0 ->
{ok, Pid}
end;
{'DOWN', Mref, _, _, Reason} ->
{error, Reason}
end.
%%% Returns {ReadMode, UnicodeMode, RealOpts}
parse_options(List) ->
parse_options(expand_encoding(List), list, latin1, []).
parse_options([], list, Uni, Acc) ->
{list,Uni,[binary|lists:reverse(Acc)]};
parse_options([], binary, Uni, Acc) ->
{binary,Uni,lists:reverse(Acc)};
parse_options([{encoding, Encoding}|T], RMode, _, Acc) ->
case valid_enc(Encoding) of
{ok, ExpandedEnc} ->
parse_options(T, RMode, ExpandedEnc, Acc);
{error,_Reason} = Error ->
Error
end;
parse_options([binary|T], _, Uni, Acc) ->
parse_options(T, binary, Uni, [binary|Acc]);
parse_options([H|T], R, U, Acc) ->
parse_options(T, R, U, [H|Acc]).
expand_encoding([]) ->
[];
expand_encoding([latin1 | T]) ->
[{encoding,latin1} | expand_encoding(T)];
expand_encoding([unicode | T]) ->
[{encoding,unicode} | expand_encoding(T)];
expand_encoding([H|T]) ->
[H|expand_encoding(T)].
valid_enc(latin1) ->
{ok,latin1};
valid_enc(utf8) ->
{ok,unicode};
valid_enc(unicode) ->
{ok,unicode};
valid_enc(utf16) ->
{ok,{utf16,big}};
valid_enc({utf16,big}) ->
{ok,{utf16,big}};
valid_enc({utf16,little}) ->
{ok,{utf16,little}};
valid_enc(utf32) ->
{ok,{utf32,big}};
valid_enc({utf32,big}) ->
{ok,{utf32,big}};
valid_enc({utf32,little}) ->
{ok,{utf32,little}};
valid_enc(_Other) ->
{error,badarg}.
server_loop(#state{mref = Mref} = State) ->
receive
{file_request, From, ReplyAs, Request} when is_pid(From) ->
case file_request(Request, State) of
{reply, Reply, NewState} ->
_ = file_reply(From, ReplyAs, Reply),
server_loop(NewState);
{error, Reply, NewState} ->
%% error is the same as reply, except that
%% it breaks the io_request_loop further down
_ = file_reply(From, ReplyAs, Reply),
server_loop(NewState);
{stop, Reason, Reply, _NewState} ->
_ = file_reply(From, ReplyAs, Reply),
exit(Reason)
end;
{io_request, From, ReplyAs, Request} when is_pid(From) ->
case io_request(Request, State) of
{reply, Reply, NewState} ->
_ = io_reply(From, ReplyAs, Reply),
server_loop(NewState);
{error, Reply, NewState} ->
%% error is the same as reply, except that
%% it breaks the io_request_loop further down
_ = io_reply(From, ReplyAs, Reply),
server_loop(NewState);
{stop, Reason, Reply, _NewState} ->
_ = io_reply(From, ReplyAs, Reply),
exit(Reason)
end;
{'DOWN', Mref, _, _, Reason} ->
exit(Reason);
_ ->
server_loop(State)
end.
file_reply(From, ReplyAs, Reply) ->
From ! {file_reply, ReplyAs, Reply}.
io_reply(From, ReplyAs, Reply) ->
From ! {io_reply, ReplyAs, Reply}.
%%%-----------------------------------------------------------------
%%% file requests
file_request({advise,Offset,Length,Advise},
#state{handle=Handle}=State) ->
case ?PRIM_FILE:advise(Handle, Offset, Length, Advise) of
{error,_}=Reply ->
{stop,normal,Reply,State};
Reply ->
{reply,Reply,State}
end;
file_request({allocate, Offset, Length},
#state{handle = Handle} = State) ->
Reply = ?PRIM_FILE:allocate(Handle, Offset, Length),
{reply, Reply, State};
file_request({pread,At,Sz},
#state{handle=Handle,buf=Buf,read_mode=ReadMode}=State) ->
case position(Handle, At, Buf) of
{ok,_Offs} ->
case ?PRIM_FILE:read(Handle, Sz) of
{ok,Bin} when ReadMode =:= list ->
std_reply({ok,binary_to_list(Bin)}, State);
Reply ->
std_reply(Reply, State)
end;
Reply ->
std_reply(Reply, State)
end;
file_request({pwrite,At,Data},
#state{handle=Handle,buf=Buf}=State) ->
case position(Handle, At, Buf) of
{ok,_Offs} ->
std_reply(?PRIM_FILE:write(Handle, Data), State);
Reply ->
std_reply(Reply, State)
end;
file_request(datasync,
#state{handle=Handle}=State) ->
case ?PRIM_FILE:datasync(Handle) of
{error,_}=Reply ->
{stop,normal,Reply,State};
Reply ->
{reply,Reply,State}
end;
file_request(sync,
#state{handle=Handle}=State) ->
case ?PRIM_FILE:sync(Handle) of
{error,_}=Reply ->
{stop,normal,Reply,State};
Reply ->
{reply,Reply,State}
end;
file_request(close,
#state{handle=Handle}=State) ->
{stop,normal,?PRIM_FILE:close(Handle),State#state{buf= <<>>}};
file_request({position,At},
#state{handle=Handle,buf=Buf}=State) ->
std_reply(position(Handle, At, Buf), State);
file_request(truncate,
#state{handle=Handle}=State) ->
case ?PRIM_FILE:truncate(Handle) of
{error,_Reason}=Reply ->
{stop,normal,Reply,State#state{buf= <<>>}};
Reply ->
{reply,Reply,State}
end;
file_request(Unknown,
#state{}=State) ->
Reason = {request, Unknown},
{error,{error,Reason},State}.
std_reply({error,_}=Reply, State) ->
{error,Reply,State#state{buf= <<>>}};
std_reply(Reply, State) ->
{reply,Reply,State#state{buf= <<>>}}.
%%%-----------------------------------------------------------------
%%% I/O request
%% New protocol with encoding tags (R13)
io_request({put_chars, Enc, Chars},
#state{buf= <<>>}=State) ->
put_chars(Chars, Enc, State);
io_request({put_chars, Enc, Chars},
#state{handle=Handle,buf=Buf}=State) ->
case position(Handle, cur, Buf) of
{error,_}=Reply ->
{stop,normal,Reply,State#state{buf= <<>>}};
_ ->
put_chars(Chars, Enc, State#state{buf= <<>>})
end;
io_request({put_chars,Enc,Mod,Func,Args},
#state{}=State) ->
case catch apply(Mod, Func, Args) of
Chars when is_list(Chars); is_binary(Chars) ->
io_request({put_chars,Enc,Chars}, State);
_ ->
{error,{error,Func},State}
end;
io_request({get_until,Enc,_Prompt,Mod,Func,XtraArgs},
#state{}=State) ->
get_chars(io_lib, get_until, {Mod, Func, XtraArgs}, Enc, State);
io_request({get_chars,Enc,_Prompt,N},
#state{}=State) ->
get_chars(N, Enc, State);
io_request({get_line,OutEnc,_Prompt}, #state{buf=Buf, read_mode=Mode, unic=InEnc} = State0) ->
try
%% Minimize the encoding conversions
WorkEnc = case InEnc of
{_,_} -> OutEnc; %% utf16 or utf32
_ -> InEnc %% Byte oriented utf8 or latin1
end,
{Res, State} = get_line(start, convert_enc(Buf, InEnc, WorkEnc), WorkEnc, State0),
{reply, cast(Res, Mode, WorkEnc, OutEnc), State}
catch exit:ExError ->
{stop,ExError,{error,ExError},State0#state{buf= <<>>}}
end;
io_request({setopts, Opts},
#state{}=State) when is_list(Opts) ->
setopts(Opts, State);
io_request(getopts,
#state{}=State) ->
getopts(State);
%% BC with pre-R13 nodes
io_request({put_chars, Chars},#state{}=State) ->
io_request({put_chars, latin1, Chars},State);
io_request({put_chars,Mod,Func,Args}, #state{}=State) ->
io_request({put_chars,latin1,Mod,Func,Args}, State);
io_request({get_until,_Prompt,Mod,Func,XtraArgs}, #state{}=State) ->
io_request({get_until,latin1,_Prompt,Mod,Func,XtraArgs}, State);
io_request({get_chars,_Prompt,N}, #state{}=State) ->
io_request({get_chars,latin1,_Prompt,N}, State);
io_request({get_line,_Prompt}, #state{}=State) ->
io_request({get_line,latin1,_Prompt}, State);
io_request({requests,Requests},
#state{}=State) when is_list(Requests) ->
io_request_loop(Requests, {reply,ok,State});
io_request(Unknown,
#state{}=State) ->
Reason = {request,Unknown},
{error,{error,Reason},State}.
%% Process a list of requests as long as the results are ok.
io_request_loop([], Result) ->
Result;
io_request_loop([_Request|_Tail],
{stop,_Reason,_Reply,_State}=Result) ->
Result;
io_request_loop([_Request|_Tail],
{error,_Reply,_State}=Result) ->
Result;
io_request_loop([Request|Tail],
{reply,_Reply,State}) ->
io_request_loop(Tail, io_request(Request, State)).
%% I/O request put_chars
%%
put_chars(Chars, latin1, #state{handle=Handle, unic=latin1}=State) ->
case ?PRIM_FILE:write(Handle, Chars) of
{error,_}=Reply ->
{stop,normal,Reply,State};
Reply ->
{reply,Reply,State}
end;
put_chars(Chars, InEncoding, #state{handle=Handle, unic=OutEncoding}=State) ->
case unicode:characters_to_binary(Chars,InEncoding,OutEncoding) of
Bin when is_binary(Bin) ->
case ?PRIM_FILE:write(Handle, Bin) of
{error,_}=Reply ->
{stop,normal,Reply,State};
Reply ->
{reply,Reply,State}
end;
{error,_,_} ->
{stop,normal,{error,{no_translation, InEncoding, OutEncoding}},State}
end.
get_line(S, {<<>>, Cont}, OutEnc,
#state{handle=Handle, read_mode=Mode, unic=InEnc}=State) ->
case ?PRIM_FILE:read(Handle, read_size(Mode)) of
{ok,Bin} ->
get_line(S, convert_enc([Cont, Bin], InEnc, OutEnc), OutEnc, State);
eof ->
get_line(S, {eof, Cont}, OutEnc, State);
{error,Reason}=Error ->
{stop,Reason,Error,State}
end;
get_line(S0, {Buf, BCont}, OutEnc, #state{unic=InEnc}=State) ->
case io_lib:collect_line(S0, Buf, OutEnc, []) of
{stop, Result, Cont0} ->
%% Convert both buffers back to file InEnc encoding
{Cont, <<>>} = convert_enc(Cont0, OutEnc, InEnc),
{Result, State#state{buf=cast_binary([Cont, BCont])}};
S ->
get_line(S, {<<>>, BCont}, OutEnc, State)
end.
convert_enc(Bins, Enc, Enc) ->
{cast_binary(Bins), <<>>};
convert_enc(eof, _, _) ->
{<<>>, <<>>};
convert_enc(Bin, InEnc, OutEnc) ->
case unicode:characters_to_binary(Bin, InEnc, OutEnc) of
Res when is_binary(Res) ->
{Res, <<>>};
{incomplete, Res, Cont} ->
{Res, Cont};
{error, _, _} ->
exit({no_translation, InEnc, OutEnc})
end.
%%
%% Process the I/O request get_chars
%%
get_chars(0, Enc, #state{read_mode=ReadMode,unic=InEncoding}=State) ->
{reply,cast(<<>>, ReadMode,InEncoding, Enc),State};
get_chars(N, Enc, #state{buf=Buf,read_mode=ReadMode,unic=latin1}=State)
when is_integer(N), N > 0, N =< byte_size(Buf) ->
{B1,B2} = split_binary(Buf, N),
{reply,cast(B1, ReadMode,latin1,Enc),State#state{buf=B2}};
get_chars(N, Enc, #state{buf=Buf,read_mode=ReadMode,unic=latin1}=State)
when is_integer(N), N > 0, N =< byte_size(Buf) ->
{B1,B2} = split_binary(Buf, N),
{reply,cast(B1, ReadMode,latin1,Enc),State#state{buf=B2}};
get_chars(N, OutEnc,#state{handle=Handle,buf=Buf,read_mode=ReadMode,unic=latin1}=State)
when is_integer(N), N > 0 ->
BufSize = byte_size(Buf),
NeedSize = N-BufSize,
Size = erlang:max(NeedSize, ?READ_SIZE_BINARY),
case ?PRIM_FILE:read(Handle, Size) of
{ok, B} ->
if BufSize+byte_size(B) < N ->
std_reply(cat(Buf, B, ReadMode,latin1,OutEnc), State);
true ->
{B1,B2} = split_binary(B, NeedSize),
{reply,cat(Buf, B1, ReadMode, latin1,OutEnc),State#state{buf=B2}}
end;
eof when BufSize =:= 0 ->
{reply,eof,State};
eof ->
std_reply(cast(Buf, ReadMode,latin1,OutEnc), State);
{error,Reason}=Error ->
{stop,Reason,Error,State#state{buf= <<>>}}
end;
get_chars(N, OutEnc,#state{handle=Handle,buf=Buf,read_mode=ReadMode,unic=InEncoding}=State)
when is_integer(N), N > 0 ->
try
%% This is rather tricky, we need to count the actual number of characters
%% in the buffer first as unicode characters are not constant in length
{BufCount, SplitPos} = count_and_find(Buf,N,InEncoding),
case BufCount >= N of
true ->
{B1,B2} = case SplitPos of
none -> {Buf,<<>>};
_ ->split_binary(Buf,SplitPos)
end,
{reply,cast(B1, ReadMode,InEncoding,OutEnc),State#state{buf=B2}};
false ->
%% Need more, Try to read 4*needed in bytes...
NeedSize = (N - BufCount) * 4,
Size = erlang:max(NeedSize, ?READ_SIZE_BINARY),
case ?PRIM_FILE:read(Handle, Size) of
{ok, B} ->
NewBuf = list_to_binary([Buf,B]),
{NewCount,NewSplit} = count_and_find(NewBuf,N,InEncoding),
case NewCount >= N of
true ->
{B01,B02} = case NewSplit of
none -> {NewBuf,<<>>};
_ ->split_binary(NewBuf, NewSplit)
end,
{reply,cast(B01, ReadMode,InEncoding,OutEnc),
State#state{buf=B02}};
false ->
%% Reached end of file
std_reply(cast(NewBuf, ReadMode,InEncoding,OutEnc),
State#state{buf = <<>>})
end;
eof when BufCount =:= 0 ->
{reply,eof,State};
eof ->
std_reply(cast(Buf, ReadMode,InEncoding,OutEnc), State#state{buf = <<>>});
{error,Reason}=Error ->
{stop,Reason,Error,State#state{buf = <<>>}}
end
end
catch
exit:ExError ->
{stop,ExError,{error,ExError},State#state{buf= <<>>}}
end;
get_chars(_N, _, #state{}=State) ->
{error,{error,get_chars},State}.
get_chars(Mod, Func, XtraArg, OutEnc, #state{buf= <<>>}=State) ->
get_chars_empty(Mod, Func, XtraArg, start, OutEnc, State);
get_chars(Mod, Func, XtraArg, OutEnc, #state{buf=Buf}=State) ->
get_chars_apply(Mod, Func, XtraArg, start, OutEnc, State#state{buf= <<>>}, Buf).
get_chars_empty(Mod, Func, XtraArg, S, latin1,
#state{handle=Handle,read_mode=ReadMode, unic=latin1}=State) ->
case ?PRIM_FILE:read(Handle, read_size(ReadMode)) of
{ok,Bin} ->
get_chars_apply(Mod, Func, XtraArg, S, latin1, State, Bin);
eof ->
get_chars_apply(Mod, Func, XtraArg, S, latin1, State, eof);
{error,Reason}=Error ->
{stop,Reason,Error,State}
end;
get_chars_empty(Mod, Func, XtraArg, S, OutEnc,
#state{handle=Handle,read_mode=ReadMode}=State) ->
case ?PRIM_FILE:read(Handle, read_size(ReadMode)) of
{ok,Bin} ->
get_chars_apply(Mod, Func, XtraArg, S, OutEnc, State, Bin);
eof ->
get_chars_apply(Mod, Func, XtraArg, S, OutEnc, State, eof);
{error,Reason}=Error ->
{stop,Reason,Error,State}
end.
get_chars_notempty(Mod, Func, XtraArg, S, OutEnc,
#state{handle=Handle,read_mode=ReadMode,buf = B}=State) ->
case ?PRIM_FILE:read(Handle, read_size(ReadMode)) of
{ok,Bin} ->
get_chars_apply(Mod, Func, XtraArg, S, OutEnc, State, list_to_binary([B,Bin]));
eof ->
case B of
<<>> ->
get_chars_apply(Mod, Func, XtraArg, S, OutEnc, State, eof);
_ ->
{stop,invalid_unicode,invalid_unicode_error(Mod, Func, XtraArg, S),State}
end;
{error,Reason}=Error ->
{stop,Reason,Error,State}
end.
get_chars_apply(Mod, Func, XtraArg, S0, latin1,
#state{read_mode=ReadMode,unic=latin1}=State, Data0) ->
Data1 = case ReadMode of
list when is_binary(Data0) -> binary_to_list(Data0);
_ -> Data0
end,
case catch Mod:Func(S0, Data1, latin1, XtraArg) of
{stop,Result,Buf} ->
{reply,Result,State#state{buf=cast_binary(Buf)}};
{'EXIT',Reason} ->
{stop,Reason,{error,err_func(Mod, Func, XtraArg)},State};
S1 ->
get_chars_empty(Mod, Func, XtraArg, S1, latin1, State)
end;
get_chars_apply(Mod, Func, XtraArg, S0, OutEnc,
#state{read_mode=ReadMode,unic=InEnc}=State, Data0) ->
try
{Data1,NewBuff} = case ReadMode of
list when is_binary(Data0) ->
case unicode:characters_to_list(Data0,InEnc) of
{Tag,Decoded,Rest} when Decoded =/= [], Tag =:= error; Decoded =/= [], Tag =:= incomplete ->
{Decoded,erlang:iolist_to_binary(Rest)};
{error, [], _} ->
exit(invalid_unicode);
{incomplete, [], R} ->
{[],R};
List when is_list(List) ->
{List,<<>>}
end;
binary when is_binary(Data0) ->
case unicode:characters_to_binary(Data0,InEnc,OutEnc) of
{Tag2,Decoded2,Rest2} when Decoded2 =/= <<>>, Tag2 =:= error; Decoded2 =/= <<>>, Tag2 =:= incomplete ->
{Decoded2,erlang:iolist_to_binary(Rest2)};
{error, <<>>, _} ->
exit(invalid_unicode);
{incomplete, <<>>, R} ->
{<<>>,R};
Binary when is_binary(Binary) ->
{Binary,<<>>}
end;
_ -> %i.e. eof
{Data0,<<>>}
end,
case catch Mod:Func(S0, Data1, OutEnc, XtraArg) of
{stop,Result,Buf} ->
{reply,Result,State#state{buf = (if
is_binary(Buf) ->
list_to_binary([unicode:characters_to_binary(Buf,OutEnc,InEnc),NewBuff]);
is_list(Buf) ->
list_to_binary([unicode:characters_to_binary(Buf,unicode,InEnc),NewBuff]);
true ->
NewBuff
end)}};
{'EXIT',Reason} ->
{stop,Reason,{error,err_func(Mod, Func, XtraArg)},State};
S1 ->
get_chars_notempty(Mod, Func, XtraArg, S1, OutEnc, State#state{buf=NewBuff})
end
catch
exit:ExReason ->
{stop,ExReason,invalid_unicode_error(Mod, Func, XtraArg, S0),State};
error:ErrReason ->
{stop,ErrReason,{error,err_func(Mod, Func, XtraArg)},State}
end.
%% A hack that tries to inform the caller about the position where the
%% error occured.
invalid_unicode_error(Mod, Func, XtraArg, S) ->
try
{erl_scan,tokens,_Args} = XtraArg,
Location = erl_scan:continuation_location(S),
{error,{Location, ?MODULE, invalid_unicode},Location}
catch
_:_ ->
{error,err_func(Mod, Func, XtraArg)}
end.
%% Convert error code to make it look as before
err_func(io_lib, get_until, {_,F,_}) ->
F.
%% Process the I/O request setopts
%%
%% setopts
setopts(Opts0,State) ->
Opts = proplists:unfold(
proplists:substitute_negations(
[{list,binary}],
expand_encoding(Opts0))),
case check_valid_opts(Opts) of
true ->
do_setopts(Opts,State);
false ->
{error,{error,enotsup},State}
end.
check_valid_opts([]) ->
true;
check_valid_opts([{binary,_}|T]) ->
check_valid_opts(T);
check_valid_opts([{encoding,_Enc}|T]) ->
check_valid_opts(T);
check_valid_opts(_) ->
false.
do_setopts(Opts, State) ->
case valid_enc(proplists:get_value(encoding, Opts, State#state.unic)) of
{ok,NewUnic} ->
case proplists:get_value(binary, Opts) of
true ->
{reply,ok,State#state{read_mode=binary, unic=NewUnic}};
false ->
{reply,ok,State#state{read_mode=list, unic=NewUnic}};
undefined ->
{reply,ok,State#state{unic=NewUnic}}
end;
_ ->
{error,{error,badarg},State}
end.
getopts(#state{read_mode=RM, unic=Unic} = State) ->
Bin = {binary, RM =:= binary},
Uni = {encoding, Unic},
{reply,[Bin,Uni],State}.
%% Concatenate two binaries and convert the result to list or binary
cat(B1, B2, binary, latin1, latin1) ->
list_to_binary([B1,B2]);
cat(B1, B2, binary, InEncoding, OutEncoding) ->
case unicode:characters_to_binary([B1,B2],InEncoding,OutEncoding) of
Good when is_binary(Good) ->
Good;
_ ->
exit({no_translation,InEncoding,OutEncoding})
end;
%% Dialyzer finds this is never used...
%% cat(B1, B2, list, InEncoding, OutEncoding) when InEncoding =/= latin1 ->
%% % Catch i.e. unicode -> latin1 errors by using the outencoding although otherwise
%% % irrelevant for lists...
%% try
%% unicode:characters_to_list(unicode:characters_to_binary([B1,B2],InEncoding,OutEncoding),
%% OutEncoding)
%% catch
%% error:_ ->
%% exit({no_translation,InEncoding,OutEncoding})
%% end.
cat(B1, B2, list, latin1,_) ->
binary_to_list(B1)++binary_to_list(B2).
%% Cast binary to list or binary
cast(eof, _, _, _) ->
eof;
cast(B, binary, latin1, latin1) ->
B;
cast(B, binary, InEncoding, OutEncoding) ->
case unicode:characters_to_binary(B,InEncoding,OutEncoding) of
Good when is_binary(Good) ->
Good;
_ ->
exit({no_translation,InEncoding,OutEncoding})
end;
cast(B, list, latin1, _) ->
binary_to_list(B);
cast(B, list, InEncoding, OutEncoding) ->
try
unicode:characters_to_list(unicode:characters_to_binary(B,InEncoding,OutEncoding),
OutEncoding)
catch
error:_ ->
exit({no_translation,InEncoding,OutEncoding})
end.
%% Convert buffer to binary
cast_binary(Binary) when is_binary(Binary) ->
Binary;
cast_binary([<<>>|List]) ->
cast_binary(List);
cast_binary(List) when is_list(List) ->
list_to_binary(List);
cast_binary(_EOF) ->
<<>>.
%% Read size for different read modes
read_size(binary) ->
?READ_SIZE_BINARY;
read_size(list) ->
?READ_SIZE_LIST.
%% Utf utility
count_and_find(Bin,N,Encoding) ->
cafu(Bin,N,0,0,none,case Encoding of
unicode -> utf8;
Oth -> Oth
end).
cafu(<<>>,0,Count,ByteCount,_SavePos,_) ->
{Count,ByteCount};
cafu(<<>>,_N,Count,_ByteCount,SavePos,_) ->
{Count,SavePos};
cafu(<<_/utf8,Rest/binary>>, 0, Count, ByteCount, _SavePos, utf8) ->
cafu(Rest,-1,Count+1,0,ByteCount,utf8);
cafu(<<_/utf8,Rest/binary>>, N, Count, _ByteCount, SavePos, utf8) when N < 0 ->
cafu(Rest,-1,Count+1,0,SavePos,utf8);
cafu(<<_/utf8,Rest/binary>> = Whole, N, Count, ByteCount, SavePos, utf8) ->
Delta = byte_size(Whole) - byte_size(Rest),
cafu(Rest,N-1,Count+1,ByteCount+Delta,SavePos,utf8);
cafu(<<_/utf16-big,Rest/binary>>, 0, Count, ByteCount, _SavePos, {utf16,big}) ->
cafu(Rest,-1,Count+1,0,ByteCount,{utf16,big});
cafu(<<_/utf16-big,Rest/binary>>, N, Count, _ByteCount, SavePos, {utf16,big}) when N < 0 ->
cafu(Rest,-1,Count+1,0,SavePos,{utf16,big});
cafu(<<_/utf16-big,Rest/binary>> = Whole, N, Count, ByteCount, SavePos, {utf16,big}) ->
Delta = byte_size(Whole) - byte_size(Rest),
cafu(Rest,N-1,Count+1,ByteCount+Delta,SavePos,{utf16,big});
cafu(<<_/utf16-little,Rest/binary>>, 0, Count, ByteCount, _SavePos, {utf16,little}) ->
cafu(Rest,-1,Count+1,0,ByteCount,{utf16,little});
cafu(<<_/utf16-little,Rest/binary>>, N, Count, _ByteCount, SavePos, {utf16,little}) when N < 0 ->
cafu(Rest,-1,Count+1,0,SavePos,{utf16,little});
cafu(<<_/utf16-little,Rest/binary>> = Whole, N, Count, ByteCount, SavePos, {utf16,little}) ->
Delta = byte_size(Whole) - byte_size(Rest),
cafu(Rest,N-1,Count+1,ByteCount+Delta,SavePos,{utf16,little});
cafu(<<_/utf32-big,Rest/binary>>, 0, Count, ByteCount, _SavePos, {utf32,big}) ->
cafu(Rest,-1,Count+1,0,ByteCount,{utf32,big});
cafu(<<_/utf32-big,Rest/binary>>, N, Count, _ByteCount, SavePos, {utf32,big}) when N < 0 ->
cafu(Rest,-1,Count+1,0,SavePos,{utf32,big});
cafu(<<_/utf32-big,Rest/binary>> = Whole, N, Count, ByteCount, SavePos, {utf32,big}) ->
Delta = byte_size(Whole) - byte_size(Rest),
cafu(Rest,N-1,Count+1,ByteCount+Delta,SavePos,{utf32,big});
cafu(<<_/utf32-little,Rest/binary>>, 0, Count, ByteCount, _SavePos, {utf32,little}) ->
cafu(Rest,-1,Count+1,0,ByteCount,{utf32,little});
cafu(<<_/utf32-little,Rest/binary>>, N, Count, _ByteCount, SavePos, {utf32,little}) when N < 0 ->
cafu(Rest,-1,Count+1,0,SavePos,{utf32,little});
cafu(<<_/utf32-little,Rest/binary>> = Whole, N, Count, ByteCount, SavePos, {utf32,little}) ->
Delta = byte_size(Whole) - byte_size(Rest),
cafu(Rest,N-1,Count+1,ByteCount+Delta,SavePos,{utf32,little});
cafu(_Other,0,Count,ByteCount,_,_) -> % Non Unicode character,
% but found our point, OK this time
{Count,ByteCount};
cafu(Other,_N,Count,0,SavePos,Enc) -> % Not enough, but valid chomped unicode
% at end.
case cbv(Enc,Other) of
false ->
exit(invalid_unicode);
_ ->
{Count,SavePos}
end;
cafu(Other,_N,Count,ByteCount,none,Enc) -> % Return what we'we got this far
% although not complete,
% it's not (yet) in error
case cbv(Enc,Other) of
false ->
exit(invalid_unicode);
_ ->
{Count,ByteCount}
end;
cafu(Other,_N,Count,_ByteCount,SavePos,Enc) -> % As above but we have
% found a position
case cbv(Enc,Other) of
false ->
exit(invalid_unicode);
_ ->
{Count,SavePos}
end.
%%
%% Bluntly stolen from stdlib/unicode.erl (cbv means can be valid?)
%%
cbv(utf8,<<1:1,1:1,0:1,_:5>>) ->
1;
cbv(utf8,<<1:1,1:1,1:1,0:1,_:4,R/binary>>) ->
case R of
<<>> ->
2;
<<1:1,0:1,_:6>> ->
1;
_ ->
false
end;
cbv(utf8,<<1:1,1:1,1:1,1:1,0:1,_:3,R/binary>>) ->
case R of
<<>> ->
3;
<<1:1,0:1,_:6>> ->
2;
<<1:1,0:1,_:6,1:1,0:1,_:6>> ->
1;
_ ->
false
end;
cbv(utf8,_) ->
false;
cbv({utf16,big},<<A:8>>) when A =< 215; A >= 224 ->
1;
cbv({utf16,big},<<54:6,_:2>>) ->
3;
cbv({utf16,big},<<54:6,_:10>>) ->
2;
cbv({utf16,big},<<54:6,_:10,55:6,_:2>>) ->
1;
cbv({utf16,big},_) ->
false;
cbv({utf16,little},<<_:8>>) ->
1; % or 3, we'll see
cbv({utf16,little},<<_:8,54:6,_:2>>) ->
2;
cbv({utf16,little},<<_:8,54:6,_:2,_:8>>) ->
1;
cbv({utf16,little},_) ->
false;
cbv({utf32,big}, <<0:8>>) ->
3;
cbv({utf32,big}, <<0:8,X:8>>) when X =< 16 ->
2;
cbv({utf32,big}, <<0:8,X:8,Y:8>>)
when X =< 16, ((X > 0) or ((Y =< 215) or (Y >= 224))) ->
1;
cbv({utf32,big},_) ->
false;
cbv({utf32,little},<<_:8>>) ->
3;
cbv({utf32,little},<<_:8,_:8>>) ->
2;
cbv({utf32,little},<<X:8,255:8,0:8>>) when X =:= 254; X =:= 255 ->
false;
cbv({utf32,little},<<_:8,Y:8,X:8>>)
when X =< 16, ((X > 0) or ((Y =< 215) or (Y >= 224))) ->
1;
cbv({utf32,little},_) ->
false.
%%%-----------------------------------------------------------------
%%% ?PRIM_FILE helpers
%% Compensates ?PRIM_FILE:position/2 for the number of bytes
%% we have buffered
position(Handle, cur, Buf) ->
position(Handle, {cur, 0}, Buf);
position(Handle, {cur, Offs}, Buf) when is_binary(Buf) ->
?PRIM_FILE:position(Handle, {cur, Offs-byte_size(Buf)});
position(Handle, At, _Buf) ->
?PRIM_FILE:position(Handle, At).
