aboutsummaryrefslogblamecommitdiffstats
path: root/lib/stdlib/src/unicode.erl
blob: 49529cffd4c48df28d048dfff0a9fd39bf42da38 (plain) (tree)
1
2
3
4
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774

                   
                                                        














                                                                         


                                                            
 
                                                                      
                                                                    
                                                                     



                                                   
                                   

                                                                   

                                                                             



                                                               

                                                               



                                                     
 





































                                                                           




                                                                       













                                            
                                                          















                                                                          





                                                                       









                                                
                                                          















                                                                            
                                                          



                                                                            







                                                                        















                                                                                                       
                                                                      



















                                                                                                     
                                                                      
















                                                                         
                                                          


















































                                                                                                 





                                                     











                                            


                                             






































































































































































































































































































































































































































































                                                                               
%%
%% %CopyrightBegin%
%% 
%% Copyright Ericsson AB 2008-2013. 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(unicode).

-export([characters_to_list/1, characters_to_list_int/2,
	 characters_to_binary/1, characters_to_binary_int/2,
	 characters_to_binary/3,
	 bom_to_encoding/1, encoding_to_bom/1]).

-export_type([chardata/0, charlist/0, encoding/0, external_chardata/0,
              external_charlist/0, latin1_char/0, latin1_chardata/0,
              latin1_charlist/0, latin1_binary/0, unicode_binary/0]).

-type encoding()  :: 'latin1' | 'unicode' | 'utf8'
                   | 'utf16' | {'utf16', endian()}
                   | 'utf32' | {'utf32', endian()}.
-type endian()    :: 'big' | 'little'.
-type unicode_binary() :: binary().
-type charlist() ::
        maybe_improper_list(char() | unicode_binary() | charlist(),
                            unicode_binary() | nil()).
-type chardata() :: charlist() | unicode_binary().
-type external_unicode_binary() :: binary().
-type external_chardata() :: external_charlist() | external_unicode_binary().
-type external_charlist() ::
        maybe_improper_list(char() |
                              external_unicode_binary() |
                              external_charlist(),
                            external_unicode_binary() | nil()).
-type latin1_binary() :: binary().
-type latin1_char() :: byte().
-type latin1_chardata() :: latin1_charlist() | latin1_binary().
-type latin1_charlist() ::
        maybe_improper_list(latin1_char() |
                              latin1_binary() |
                              latin1_charlist(),
                            latin1_binary() | nil()).

%%% BIFs
%%%
%%% characters_to_binary/2 (will trap to characters_to_binary_int/2
%%%                         if InEncoding is not {latin1 | unicode | utf8})
%%% characters_to_list/2   (will trap to characters_to_list_int/2 if
%%%                         InEncoding is not {latin1 | unicode | utf8})

-export([bin_is_7bit/1, characters_to_binary/2, characters_to_list/2]).

-spec bin_is_7bit(Binary) -> boolean() when
      Binary :: binary().

bin_is_7bit(_) ->
    erlang:nif_error(undef).

-spec characters_to_binary(Data, InEncoding) -> Result when
      Data :: latin1_chardata() | chardata() | external_chardata(),
      InEncoding :: encoding(),
      Result :: binary()
              | {error, binary(), RestData}
              | {incomplete, binary(), binary()},
      RestData :: latin1_chardata() | chardata() | external_chardata().

characters_to_binary(_, _) ->
    erlang:nif_error(undef).

-spec characters_to_list(Data,  InEncoding) -> Result when
      Data :: latin1_chardata() | chardata() | external_chardata(),
      InEncoding :: encoding(),
      Result :: list()
              | {error, list(), RestData}
              | {incomplete, list(), binary()},
      RestData :: latin1_chardata() | chardata() | external_chardata().

characters_to_list(_, _) ->
    erlang:nif_error(undef).

%%% End of BIFs

-spec characters_to_list(Data) -> Result when
      Data :: latin1_chardata() | chardata() | external_chardata(),
      Result :: list()
              | {error, list(), RestData}
              | {incomplete, list(), binary()},
      RestData :: latin1_chardata() | chardata() | external_chardata().

characters_to_list(ML) ->
    unicode:characters_to_list(ML,unicode).

characters_to_list_int(ML, Encoding) ->
    try
	do_characters_to_list(ML,Encoding)
    catch
	error:AnyError ->
	    TheError = case AnyError of
			   system_limit ->
			       system_limit;
			   _ ->
			       badarg
		       end,
	    {'EXIT',{new_stacktrace,[{Mod,_,L,_}|Rest]}} =
		(catch erlang:error(new_stacktrace,
				    [ML,Encoding])),
	    erlang:raise(error,TheError,[{Mod,characters_to_list,L}|Rest])
    end.

% XXX: Optimize me!
do_characters_to_list(ML, Encoding) -> 
    case unicode:characters_to_binary(ML,Encoding) of
	Bin when is_binary(Bin) ->
	    unicode:characters_to_list(Bin,utf8); 
	{error,Encoded,Rest} ->
	    {error,unicode:characters_to_list(Encoded,utf8),Rest};
	{incomplete, Encoded2, Rest2} ->
	    {incomplete,unicode:characters_to_list(Encoded2,utf8),Rest2}
    end.


-spec characters_to_binary(Data) -> Result when
      Data :: latin1_chardata() | chardata() | external_chardata(),
      Result :: binary()
              | {error, binary(), RestData}
              | {incomplete, binary(), binary()},
      RestData :: latin1_chardata() | chardata() | external_chardata().

characters_to_binary(ML) ->
    try
	unicode:characters_to_binary(ML,unicode)
    catch
	error:AnyError ->
	    TheError = case AnyError of
			   system_limit ->
			       system_limit;
			   _ ->
			       badarg
		       end,
	    {'EXIT',{new_stacktrace,[{Mod,_,L,_}|Rest]}} =
		(catch erlang:error(new_stacktrace,
				    [ML])),
	    erlang:raise(error,TheError,[{Mod,characters_to_binary,L}|Rest])
    end.
	

characters_to_binary_int(ML,InEncoding) ->
    try
	characters_to_binary_int(ML,InEncoding,unicode)
    catch
	error:AnyError ->
	    TheError = case AnyError of
			   system_limit ->
			       system_limit;
			   _ ->
			       badarg
		       end,
	    {'EXIT',{new_stacktrace,[{Mod,_,L,_}|Rest]}} =
		(catch erlang:error(new_stacktrace,
				    [ML,InEncoding])),
	    erlang:raise(error,TheError,[{Mod,characters_to_binary,L}|Rest])
    end.

-spec characters_to_binary(Data, InEncoding, OutEncoding) -> Result when
      Data :: latin1_chardata() | chardata() | external_chardata(),
      InEncoding :: encoding(),
      OutEncoding :: encoding(),
      Result :: binary()
              | {error, binary(), RestData}
              | {incomplete, binary(), binary()},
      RestData :: latin1_chardata() | chardata() | external_chardata().

characters_to_binary(ML, latin1, latin1) when is_binary(ML) ->
    ML;
characters_to_binary(ML, latin1, Uni) when is_binary(ML) and ((Uni =:= utf8) or   (Uni =:= unicode)) ->
    case unicode:bin_is_7bit(ML) of
	true ->
	    ML;
	false ->
	        try
		    characters_to_binary_int(ML,latin1,utf8)
		catch
		    error:AnyError ->	    
			TheError = case AnyError of
				       system_limit ->
					   system_limit;
				       _ ->
					   badarg
				   end,
			{'EXIT',{new_stacktrace,[{Mod,_,L,_}|Rest]}} =
			    (catch erlang:error(new_stacktrace,
						[ML,latin1,Uni])),
			erlang:raise(error,TheError,
				     [{Mod,characters_to_binary,L}|Rest])
		end
    end;
characters_to_binary(ML,Uni,latin1) when is_binary(ML) and ((Uni =:= utf8) or   (Uni =:= unicode)) ->
    case unicode:bin_is_7bit(ML) of
	true ->
	    ML;
	false ->
	        try
		    characters_to_binary_int(ML,utf8,latin1)
		catch
		    error:AnyError ->
			TheError = case AnyError of
				       system_limit ->
					   system_limit;
				       _ ->
					   badarg
				   end,
			{'EXIT',{new_stacktrace,[{Mod,_,L,_}|Rest]}} =
			    (catch erlang:error(new_stacktrace,
						[ML,Uni,latin1])),
			erlang:raise(error,TheError,
				     [{Mod,characters_to_binary,L}|Rest])
		end
    end;
    
characters_to_binary(ML, InEncoding, OutEncoding) ->
    try
	characters_to_binary_int(ML,InEncoding,OutEncoding)
    catch
	error:AnyError ->
	    TheError = case AnyError of
			   system_limit ->
			       system_limit;
			   _ ->
			       badarg
		       end,
	    {'EXIT',{new_stacktrace,[{Mod,_,L,_}|Rest]}} =
		(catch erlang:error(new_stacktrace,
				    [ML,InEncoding,OutEncoding])),
	    erlang:raise(error,TheError,[{Mod,characters_to_binary,L}|Rest])
    end.

characters_to_binary_int(ML, InEncoding, OutEncoding) when 
    InEncoding =:= latin1, OutEncoding =:= unicode; 
    InEncoding =:= latin1, OutEncoding =:= utf8;
    InEncoding =:= unicode, OutEncoding =:= unicode; 
    InEncoding =:= unicode, OutEncoding =:= utf8; 
    InEncoding =:= utf8, OutEncoding =:= unicode; 
    InEncoding =:= utf8, OutEncoding =:= utf8 -> 
    unicode:characters_to_binary(ML,InEncoding);

characters_to_binary_int(ML, InEncoding, OutEncoding) ->
    {InTrans,Limit} = case OutEncoding of
		  latin1 -> {i_trans_chk(InEncoding),255};
		  _ -> {i_trans(InEncoding),case InEncoding of latin1 -> 255; _ -> 16#10FFFF end}
	      end,
    OutTrans = o_trans(OutEncoding),
    Res = 
	ml_map(ML,
	       fun(Part,Accum) when is_binary(Part) ->
		       case InTrans(Part) of
			   List when is_list(List) ->
			       Tail = OutTrans(List),
			       <<Accum/binary, Tail/binary>>;
			   {error, Translated, Rest} -> 
			       Tail = OutTrans(Translated),
			       {error, <<Accum/binary,Tail/binary>>, Rest};
			   {incomplete, Translated, Rest, Missing}  ->
			       Tail = OutTrans(Translated),
			       {incomplete, <<Accum/binary,Tail/binary>>, Rest,
				Missing}
		       end;
		  (Part, Accum) when is_integer(Part), Part =< Limit ->
		       case OutTrans([Part]) of
			   Binary when is_binary(Binary) ->
			       <<Accum/binary, Binary/binary>>;
			   {error, _, [Part]} ->
			       {error,Accum,[Part]}
		       end;
		  (Part, Accum) ->
		       {error, Accum, [Part]}
	       end,<<>>),
    case Res of
	{incomplete,A,B,_} ->
	    {incomplete,A,B};
	_ ->
	    Res
    end.

-spec bom_to_encoding(Bin) -> {Encoding, Length} when
      Bin :: binary(),
      Encoding ::  'latin1' | 'utf8'
                 | {'utf16', endian()}
                 | {'utf32', endian()},
      Length :: non_neg_integer().

bom_to_encoding(<<239,187,191,_/binary>>) ->
    {utf8,3};
bom_to_encoding(<<0,0,254,255,_/binary>>) ->
    {{utf32,big},4};
bom_to_encoding(<<255,254,0,0,_/binary>>) ->
    {{utf32,little},4};
bom_to_encoding(<<254,255,_/binary>>) ->
    {{utf16,big},2};
bom_to_encoding(<<255,254,_/binary>>) ->
    {{utf16,little},2};
bom_to_encoding(Bin) when is_binary(Bin) ->
    {latin1,0}.

-spec encoding_to_bom(InEncoding) -> Bin when
      Bin :: binary(),
      InEncoding :: encoding().

encoding_to_bom(unicode) ->
    <<239,187,191>>;
encoding_to_bom(utf8) ->
    <<239,187,191>>;
encoding_to_bom(utf16) ->
    <<254,255>>;
encoding_to_bom({utf16,big}) ->
    <<254,255>>;
encoding_to_bom({utf16,little}) ->
    <<255,254>>;
encoding_to_bom(utf32) ->
    <<0,0,254,255>>;
encoding_to_bom({utf32,big}) ->
    <<0,0,254,255>>;
encoding_to_bom({utf32,little}) ->
    <<255,254,0,0>>;
encoding_to_bom(latin1) ->
    <<>>.
	    

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.


ml_map([],_,{{Inc,X},Accum}) ->
    {incomplete, Accum, Inc, X};
ml_map([],_Fun,Accum) ->
    Accum;
ml_map([Part|_] = Whole,_,{{Incomplete, _}, Accum}) when is_integer(Part) ->
    {error, Accum, [Incomplete | Whole]};
ml_map([Part|T],Fun,Accum) when is_integer(Part) ->
    case Fun(Part,Accum) of
	Bin when is_binary(Bin) ->
	    case ml_map(T,Fun,Bin) of
		Bin2 when is_binary(Bin2) ->
		    Bin2;
		{error, Converted, Rest} ->
		    {error, Converted, Rest}; 
		{incomplete, Converted, Rest,X} -> 
		    {incomplete, Converted, Rest,X}
	    end;
	% Can not be incomplete - it's an integer
	{error, Converted, Rest} ->
	    {error, Converted, [Rest|T]}
    end;
ml_map([Part|T],Fun,{{Incomplete,Missing}, Accum}) when is_binary(Part) ->
    % Ok, how much is needed to fill in the incomplete part?
    case byte_size(Part) of
	N when N >= Missing ->
	    <<FillIn:Missing/binary,Trailing/binary>> = Part,
	    NewPart = <<Incomplete/binary,FillIn/binary>>,
	    ml_map([NewPart,Trailing|T], Fun, Accum);
	M ->
	    NewIncomplete = <<Incomplete/binary, Part/binary>>,
	    NewMissing = Missing - M,
	    ml_map(T,Fun,{{NewIncomplete, NewMissing}, Accum})
    end;
ml_map([Part|T],Fun,Accum) when is_binary(Part), byte_size(Part) > 8192 ->
    <<Part1:8192/binary,Part2/binary>> = Part,
    ml_map([Part1,Part2|T],Fun,Accum);
ml_map([Part|T],Fun,Accum) when is_binary(Part) ->
    case Fun(Part,Accum) of
	Bin when is_binary(Bin) ->
	    ml_map(T,Fun,Bin);
	{incomplete, Converted, Rest, Missing} ->
	    ml_map(T,Fun,{{Rest, Missing},Converted});
	{error, Converted, Rest} ->
	    {error, Converted, [Rest|T]}
    end;
ml_map([List|T],Fun,Accum) when is_list(List) ->
    case ml_map(List,Fun,Accum) of
	Bin when is_binary(Bin) ->
	    ml_map(T,Fun,Bin);
	{error, Converted,Rest} ->
	    {error, Converted, [Rest | T]};
	{incomplete, Converted,Rest,N} ->
	    ml_map(T,Fun,{{Rest,N},Converted})
    end;
ml_map(Bin,Fun,{{Incomplete,Missing},Accum}) when is_binary(Bin) ->
    case byte_size(Bin) of
	N when N >= Missing ->
	    ml_map([Incomplete,Bin],Fun,Accum);
	M ->
	    {incomplete, Accum, <<Incomplete/binary, Bin/binary>>, Missing - M}
    end;
ml_map(Part,Fun,Accum) when is_binary(Part), byte_size(Part) > 8192 ->
     <<Part1:8192/binary,Part2/binary>> = Part,
    ml_map([Part1,Part2],Fun,Accum);
ml_map(Bin,Fun,Accum) when is_binary(Bin) ->
    Fun(Bin,Accum).

 



i_trans(latin1) ->
    fun(Bin) -> binary_to_list(Bin) end;
i_trans(unicode) ->
    i_trans(utf8);
i_trans(utf8) ->
    fun do_i_utf8/1;
i_trans(utf16) ->
    fun do_i_utf16_big/1;
i_trans({utf16,big}) ->
    fun do_i_utf16_big/1;
i_trans({utf16,little}) ->
    fun do_i_utf16_little/1;
i_trans(utf32) ->
    fun do_i_utf32_big/1;
i_trans({utf32,big}) ->
    fun do_i_utf32_big/1;
i_trans({utf32,little}) ->
    fun do_i_utf32_little/1.

i_trans_chk(latin1) ->
    fun(Bin) -> binary_to_list(Bin) end;
i_trans_chk(unicode) ->
    i_trans_chk(utf8);
i_trans_chk(utf8) ->
    fun do_i_utf8_chk/1;
i_trans_chk(utf16) ->
    fun do_i_utf16_big_chk/1;
i_trans_chk({utf16,big}) ->
    fun do_i_utf16_big_chk/1;
i_trans_chk({utf16,little}) ->
    fun do_i_utf16_little_chk/1;
i_trans_chk(utf32) ->
    fun do_i_utf32_big_chk/1;
i_trans_chk({utf32,big}) ->
    fun do_i_utf32_big_chk/1;
i_trans_chk({utf32,little}) ->
    fun do_i_utf32_little_chk/1.

o_trans(latin1) ->
    fun(L) -> list_to_binary(L) end;
o_trans(unicode) ->
    o_trans(utf8);
o_trans(utf8) ->
    fun(L) ->
	    do_o_binary(fun(One) ->
				<<One/utf8>>
			end, L)
    end;
    
o_trans(utf16) ->
    fun(L) ->
	    do_o_binary(fun(One) ->
				<<One/utf16>>
			end, L)
    end;
o_trans({utf16,big}) ->
    o_trans(utf16);
o_trans({utf16,little}) ->
    fun(L) ->
	    do_o_binary(fun(One) ->
				<<One/utf16-little>>
			end, L)
    end;
o_trans(utf32) ->
    fun(L) ->
	    do_o_binary(fun(One) ->
				<<One/utf32>>
			end, L)
    end;
o_trans({utf32,big}) ->
    o_trans(utf32);
o_trans({utf32,little}) ->
    fun(L) ->
	    do_o_binary(fun(One) ->
				<<One/utf32-little>>
			end, L)
    end.

do_o_binary(F,L) ->
    case do_o_binary2(F,L) of
	{Tag,List,R} ->
	    {Tag,erlang:iolist_to_binary(List),R};
	List ->
	    erlang:iolist_to_binary(List)
    end.

do_o_binary2(_F,[]) ->
    <<>>;
do_o_binary2(F,[H|T]) ->
    case (catch F(H)) of
	{'EXIT',_} ->
	    {error,<<>>,[H|T]};
	Bin when is_binary(Bin) ->
	    case do_o_binary2(F,T) of
		{error,Bin2,Rest} ->
		    {error,[Bin|Bin2],Rest};
		Bin3 ->
		    [Bin|Bin3]
	    end
    end.
 
%% Specific functions only allowing codepoints in latin1 range
	
do_i_utf8_chk(<<>>) ->
    [];
do_i_utf8_chk(<<U/utf8,R/binary>>) when U =< 255 ->
    case do_i_utf8_chk(R) of
	{error,Trans,Rest} ->
	    {error, [U|Trans], Rest};
	{incomplete,Trans,Rest,N} ->
	    {incomplete, [U|Trans], Rest, N};
	L when is_list(L) ->
	    [U|L]
    end;
do_i_utf8_chk(<<_/utf8,_/binary>> = Bin) ->
    {error, [], Bin};
do_i_utf8_chk(Bin) when is_binary(Bin) ->
    case cbv(utf8,Bin) of
	N when is_integer(N) ->
	    {incomplete, [], Bin,N};
	false ->
	    {error, [], Bin}
    end.
do_i_utf16_big_chk(<<>>) ->
    [];
do_i_utf16_big_chk(<<U/utf16,R/binary>>) when U =< 255 ->
    case do_i_utf16_big_chk(R) of
	{error,Trans,Rest} ->
	    {error, [U|Trans], Rest};
	{incomplete,Trans,Rest,N} ->
	    {incomplete, [U|Trans], Rest, N};
	L when is_list(L) ->
	    [U|L]
    end;
do_i_utf16_big_chk(<<_/utf16,_/binary>> = Bin) ->
    {error, [], Bin};
do_i_utf16_big_chk(Bin) when is_binary(Bin) ->
    case cbv({utf16,big},Bin) of
	N when is_integer(N) ->
	    {incomplete, [], Bin, N};
	false ->
	    {error, [], Bin}
    end.
do_i_utf16_little_chk(<<>>) ->
    [];
do_i_utf16_little_chk(<<U/utf16-little,R/binary>>) when U =< 255 ->
    case do_i_utf16_little_chk(R) of
	{error,Trans,Rest} ->
	    {error, [U|Trans], Rest};
	{incomplete,Trans,Rest,N} ->
	    {incomplete, [U|Trans], Rest, N};
	L when is_list(L) ->
	    [U|L]
    end;
do_i_utf16_little_chk(<<_/utf16-little,_/binary>> = Bin) ->
    {error, [], Bin};
do_i_utf16_little_chk(Bin) when is_binary(Bin) ->
    case cbv({utf16,little},Bin) of
	N when is_integer(N) ->
	    {incomplete, [], Bin, N};
	false ->
	    {error, [], Bin}
    end.


do_i_utf32_big_chk(<<>>) ->
    [];
do_i_utf32_big_chk(<<U/utf32,R/binary>>) when U =< 255 ->
    case do_i_utf32_big_chk(R) of
	{error,Trans,Rest} ->
	    {error, [U|Trans], Rest};
	L when is_list(L) ->
	    [U|L]
    end;
do_i_utf32_big_chk(<<_/utf32,_/binary>> = Bin) ->
    {error, [], Bin};
do_i_utf32_big_chk(Bin) when is_binary(Bin) ->
    case cbv({utf32,big},Bin) of
	N when is_integer(N) ->
	    {incomplete, [], Bin, N};
	false ->
	    {error, [], Bin}
    end.
do_i_utf32_little_chk(<<>>) ->
    [];
do_i_utf32_little_chk(<<U/utf32-little,R/binary>>) when U =< 255 ->
    case do_i_utf32_little_chk(R) of
	{error,Trans,Rest} ->
	    {error, [U|Trans], Rest};
	L when is_list(L) ->
	    [U|L]
    end;
do_i_utf32_little_chk(<<_/utf32-little,_/binary>> = Bin) ->
    {error, [], Bin};
do_i_utf32_little_chk(Bin) when is_binary(Bin) ->
    case cbv({utf32,little},Bin) of
	N when is_integer(N) ->
	    {incomplete, [], Bin, N};
	false ->
	    {error, [], Bin}
    end.


%% General versions

do_i_utf8(<<>>) ->
    [];
do_i_utf8(<<U/utf8,R/binary>>) ->
    case do_i_utf8(R) of
	{error,Trans,Rest} ->
	    {error, [U|Trans], Rest};
	{incomplete,Trans,Rest,N} ->
	    {incomplete, [U|Trans], Rest, N};
	L when is_list(L) ->
	    [U|L]
    end;
do_i_utf8(Bin) when is_binary(Bin) ->
    case cbv(utf8,Bin) of
	N when is_integer(N) ->
	    {incomplete, [], Bin,N};
	false ->
	    {error, [], Bin}
    end.

do_i_utf16_big(<<>>) ->
    [];
do_i_utf16_big(<<U/utf16,R/binary>>) ->
    case do_i_utf16_big(R) of
	{error,Trans,Rest} ->
	    {error, [U|Trans], Rest};
	{incomplete,Trans,Rest,N} ->
	    {incomplete, [U|Trans], Rest, N};
	L when is_list(L) ->
	    [U|L]
    end;
do_i_utf16_big(Bin) when is_binary(Bin) ->
    case cbv({utf16,big},Bin) of
	N when is_integer(N) ->
	    {incomplete, [], Bin, N};
	false ->
	    {error, [], Bin}
    end.
do_i_utf16_little(<<>>) ->
    [];
do_i_utf16_little(<<U/utf16-little,R/binary>>) ->
    case do_i_utf16_little(R) of
	{error,Trans,Rest} ->
	    {error, [U|Trans], Rest};
	{incomplete,Trans,Rest,N} ->
	    {incomplete, [U|Trans], Rest, N};
	L when is_list(L) ->
	    [U|L]
    end;
do_i_utf16_little(Bin) when is_binary(Bin) ->
    case cbv({utf16,little},Bin) of
	N when is_integer(N) ->
	    {incomplete, [], Bin, N};
	false ->
	    {error, [], Bin}
    end.


do_i_utf32_big(<<>>) ->
    [];
do_i_utf32_big(<<U/utf32,R/binary>>) ->
    case do_i_utf32_big(R) of
	{error,Trans,Rest} ->
	    {error, [U|Trans], Rest};
	{incomplete,Trans,Rest,N} ->
	    {incomplete, [U|Trans], Rest, N};
	L when is_list(L) ->
	    [U|L]
    end;
do_i_utf32_big(Bin) when is_binary(Bin) ->
    case cbv({utf32,big},Bin) of
	N when is_integer(N) ->
	    {incomplete, [], Bin, N};
	false ->
	    {error, [], Bin}
    end.
do_i_utf32_little(<<>>) ->
    [];
do_i_utf32_little(<<U/utf32-little,R/binary>>) ->
    case do_i_utf32_little(R) of
	{error,Trans,Rest} ->
	    {error, [U|Trans], Rest};
	{incomplete,Trans,Rest,N} ->
	    {incomplete, [U|Trans], Rest, N};
	L when is_list(L) ->
	    [U|L]
    end;
do_i_utf32_little(Bin) when is_binary(Bin) ->
    case cbv({utf32,little},Bin) of
	N when is_integer(N) ->
	    {incomplete, [], Bin, N};
	false ->
	    {error, [], Bin}
    end.