%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1996-2017. 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_lib_pretty).
%%% Pretty printing Erlang terms
%%%
%%% In this module "print" means the formatted printing while "write"
%%% means just writing out onto one line.
-export([print/1,print/2,print/3,print/4,print/5,print/6]).
%%%
%%% Exported functions
%%%
%% print(Term) -> [Chars]
%% print(Term, Column, LineLength, Depth) -> [Chars]
%% Depth = -1 gives unlimited print depth. Use io_lib:write for atomic terms.
-spec print(term()) -> io_lib:chars().
print(Term) ->
print(Term, 1, 80, -1).
%% print(Term, RecDefFun) -> [Chars]
%% print(Term, Depth, RecDefFun) -> [Chars]
%% RecDefFun = fun(Tag, NoFields) -> [FieldTag] | no
%% Used by the shell for printing records and for Unicode.
-type rec_print_fun() :: fun((Tag :: atom(), NFields :: non_neg_integer()) ->
no | [FieldName :: atom()]).
-type column() :: integer().
-type line_length() :: pos_integer().
-type depth() :: integer().
-type max_chars() :: integer().
-type chars() :: io_lib:chars().
-type option() :: {column, column()}
| {line_length, line_length()}
| {depth, depth()}
| {max_chars, max_chars()}
| {record_print_fun, rec_print_fun()}
| {strings, boolean()}
| {encoding, latin1 | utf8 | unicode}.
-type options() :: [option()].
-spec print(term(), rec_print_fun()) -> chars();
(term(), options()) -> chars().
print(Term, Options) when is_list(Options) ->
Col = get_option(column, Options, 1),
Ll = get_option(line_length, Options, 80),
D = get_option(depth, Options, -1),
M = get_option(max_chars, Options, -1),
RecDefFun = get_option(record_print_fun, Options, no_fun),
Encoding = get_option(encoding, Options, epp:default_encoding()),
Strings = get_option(strings, Options, true),
print(Term, Col, Ll, D, M, RecDefFun, Encoding, Strings);
print(Term, RecDefFun) ->
print(Term, -1, RecDefFun).
-spec print(term(), depth(), rec_print_fun()) -> chars().
print(Term, Depth, RecDefFun) ->
print(Term, 1, 80, Depth, RecDefFun).
-spec print(term(), column(), line_length(), depth()) -> chars().
print(Term, Col, Ll, D) ->
print(Term, Col, Ll, D, _M=-1, no_fun, latin1, true).
-spec print(term(), column(), line_length(), depth(), rec_print_fun()) ->
chars().
print(Term, Col, Ll, D, RecDefFun) ->
print(Term, Col, Ll, D, _M=-1, RecDefFun).
-spec print(term(), column(), line_length(), depth(), max_chars(),
rec_print_fun()) -> chars().
print(Term, Col, Ll, D, M, RecDefFun) ->
print(Term, Col, Ll, D, M, RecDefFun, latin1, true).
print(_, _, _, 0, _M, _RF, _Enc, _Str) -> "...";
print(Term, Col, Ll, D, M, RecDefFun, Enc, Str) when Col =< 0 ->
print(Term, 1, Ll, D, M, RecDefFun, Enc, Str);
print(Term, Col, Ll, D, M0, RecDefFun, Enc, Str) when is_tuple(Term);
is_list(Term);
is_map(Term);
is_bitstring(Term) ->
If = {_S, Len} = print_length(Term, D, RecDefFun, Enc, Str),
M = max_cs(M0, Len),
if
Len < Ll - Col, Len =< M ->
write(If);
true ->
TInd = while_fail([-1, 4],
fun(I) -> cind(If, Col, Ll, M, I, 0, 0) end,
1),
pp(If, Col, Ll, M, TInd, indent(Col), 0, 0)
end;
print(Term, _Col, _Ll, _D, _M, _RF, _Enc, _Str) ->
io_lib:write(Term).
%%%
%%% Local functions
%%%
max_cs(M, Len) when M < 0 ->
Len;
max_cs(M, _Len) ->
M.
-define(ATM(T), is_list(element(1, T))).
-define(ATM_PAIR(Pair),
?ATM(element(2, element(1, Pair))) % Key
andalso
?ATM(element(3, element(1, Pair)))). % Value
-define(ATM_FLD(Field), ?ATM(element(4, element(1, Field)))).
pp({_S, Len} = If, Col, Ll, M, _TInd, _Ind, LD, W)
when Len < Ll - Col - LD, Len + W + LD =< M ->
write(If);
pp({{list,L}, _Len}, Col, Ll, M, TInd, Ind, LD, W) ->
[$[, pp_list(L, Col + 1, Ll, M, TInd, indent(1, Ind), LD, $|, W + 1), $]];
pp({{tuple,true,L}, _Len}, Col, Ll, M, TInd, Ind, LD, W) ->
[${, pp_tag_tuple(L, Col, Ll, M, TInd, Ind, LD, W + 1), $}];
pp({{tuple,false,L}, _Len}, Col, Ll, M, TInd, Ind, LD, W) ->
[${, pp_list(L, Col + 1, Ll, M, TInd, indent(1, Ind), LD, $,, W + 1), $}];
pp({{map,Pairs},_Len}, Col, Ll, M, TInd, Ind, LD, W) ->
[$#, ${, pp_map(Pairs, Col + 2, Ll, M, TInd, indent(2, Ind), LD, W + 1),
$}];
pp({{record,[{Name,NLen} | L]}, _Len}, Col, Ll, M, TInd, Ind, LD, W) ->
[Name, ${, pp_record(L, NLen, Col, Ll, M, TInd, Ind, LD, W + NLen+1), $}];
pp({{bin,S}, _Len}, Col, Ll, M, _TInd, Ind, LD, W) ->
pp_binary(S, Col + 2, Ll, M, indent(2, Ind), LD, W);
pp({S, _Len}, _Col, _Ll, _M, _TInd, _Ind, _LD, _W) ->
S.
%% Print a tagged tuple by indenting the rest of the elements
%% differently to the tag. Tuple has size >= 2.
pp_tag_tuple([{Tag,Tlen} | L], Col, Ll, M, TInd, Ind, LD, W) ->
TagInd = Tlen + 2,
Tcol = Col + TagInd,
S = $,,
if
TInd > 0, TagInd > TInd ->
Col1 = Col + TInd,
Indent = indent(TInd, Ind),
[Tag|pp_tail(L, Col1, Tcol, Ll, M, TInd, Indent, LD, S, W+Tlen)];
true ->
Indent = indent(TagInd, Ind),
[Tag, S | pp_list(L, Tcol, Ll, M, TInd, Indent, LD, S, W+Tlen+1)]
end.
pp_map([], _Col, _Ll, _M, _TInd, _Ind, _LD, _W) ->
"";
pp_map({dots, _}, _Col, _Ll, _M, _TInd, _Ind, _LD, _W) ->
"...";
pp_map([P | Ps], Col, Ll, M, TInd, Ind, LD, W) ->
{PS, PW} = pp_pair(P, Col, Ll, M, TInd, Ind, last_depth(Ps, LD), W),
[PS | pp_pairs_tail(Ps, Col, Col + PW, Ll, M, TInd, Ind, LD, PW)].
pp_pairs_tail([], _Col0, _Col, _Ll, _M, _TInd, _Ind, _LD, _W) ->
"";
pp_pairs_tail({dots, _}, _Col0, _Col, _M, _Ll, _TInd, _Ind, _LD, _W) ->
",...";
pp_pairs_tail([{_, Len}=P | Ps], Col0, Col, Ll, M, TInd, Ind, LD, W) ->
LD1 = last_depth(Ps, LD),
ELen = 1 + Len,
if
LD1 =:= 0, ELen + 1 < Ll - Col, W + ELen + 1 =< M, ?ATM_PAIR(P);
LD1 > 0, ELen < Ll - Col - LD1, W + ELen + LD1 =< M, ?ATM_PAIR(P) ->
[$,, write_pair(P) |
pp_pairs_tail(Ps, Col0, Col+ELen, Ll, M, TInd, Ind, LD, W+ELen)];
true ->
{PS, PW} = pp_pair(P, Col0, Ll, M, TInd, Ind, LD1, 0),
[$,, $\n, Ind, PS |
pp_pairs_tail(Ps, Col0, Col0 + PW, Ll, M, TInd, Ind, LD, PW)]
end.
pp_pair({_, Len}=Pair, Col, Ll, M, _TInd, _Ind, LD, W)
when Len < Ll - Col - LD, Len + W + LD =< M ->
{write_pair(Pair), if
?ATM_PAIR(Pair) ->
Len;
true ->
Ll % force nl
end};
pp_pair({{map_pair, K, V}, _Len}, Col0, Ll, M, TInd, Ind0, LD, W) ->
I = map_value_indent(TInd),
Ind = indent(I, Ind0),
{[pp(K, Col0, Ll, M, TInd, Ind0, LD, W), " =>\n",
Ind | pp(V, Col0 + I, Ll, M, TInd, Ind, LD, 0)], Ll}. % force nl
pp_record([], _Nlen, _Col, _Ll, _M, _TInd, _Ind, _LD, _W) ->
"";
pp_record({dots, _}, _Nlen, _Col, _Ll, _M, _TInd, _Ind, _LD, _W) ->
"...";
pp_record([F | Fs], Nlen, Col0, Ll, M, TInd, Ind0, LD, W0) ->
Nind = Nlen + 1,
{Col, Ind, S, W} = rec_indent(Nind, TInd, Col0, Ind0, W0),
{FS, FW} = pp_field(F, Col, Ll, M, TInd, Ind, last_depth(Fs, LD), W),
[S, FS | pp_fields_tail(Fs, Col, Col + FW, Ll, M, TInd, Ind, LD, W + FW)].
pp_fields_tail([], _Col0, _Col, _Ll, _M, _TInd, _Ind, _LD, _W) ->
"";
pp_fields_tail({dots, _}, _Col0, _Col, _M, _Ll, _TInd, _Ind, _LD, _W) ->
",...";
pp_fields_tail([{_, Len}=F | Fs], Col0, Col, Ll, M, TInd, Ind, LD, W) ->
LD1 = last_depth(Fs, LD),
ELen = 1 + Len,
if
LD1 =:= 0, ELen + 1 < Ll - Col, W + ELen + 1 =< M, ?ATM_FLD(F);
LD1 > 0, ELen < Ll - Col - LD1, W + ELen + LD1 =< M, ?ATM_FLD(F) ->
[$,, write_field(F) |
pp_fields_tail(Fs, Col0, Col+ELen, Ll, M, TInd, Ind, LD, W+ELen)];
true ->
{FS, FW} = pp_field(F, Col0, Ll, M, TInd, Ind, LD1, 0),
[$,, $\n, Ind, FS |
pp_fields_tail(Fs, Col0, Col0 + FW, Ll, M, TInd, Ind, LD, FW)]
end.
pp_field({_, Len}=Fl, Col, Ll, M, _TInd, _Ind, LD, W)
when Len < Ll - Col - LD, Len + W + LD =< M ->
{write_field(Fl), if
?ATM_FLD(Fl) ->
Len;
true ->
Ll % force nl
end};
pp_field({{field, Name, NameL, F}, _Len}, Col0, Ll, M, TInd, Ind0, LD, W0) ->
{Col, Ind, S, W} = rec_indent(NameL, TInd, Col0, Ind0, W0 + NameL),
Sep = case S of
[$\n | _] -> " =";
_ -> " = "
end,
{[Name, Sep, S | pp(F, Col, Ll, M, TInd, Ind, LD, W)], Ll}. % force nl
rec_indent(RInd, TInd, Col0, Ind0, W0) ->
Nl = (TInd > 0) and (RInd > TInd),
DCol = case Nl of
true -> TInd;
false -> RInd
end,
Col = Col0 + DCol,
Ind = indent(DCol, Ind0),
S = case Nl of
true -> [$\n | Ind];
false -> ""
end,
W = case Nl of
true -> 0;
false -> W0
end,
{Col, Ind, S, W}.
pp_list({dots, _}, _Col0, _Ll, _M, _TInd, _Ind, _LD, _S, _W) ->
"...";
pp_list([E | Es], Col0, Ll, M, TInd, Ind, LD, S, W) ->
{ES, WE} = pp_element(E, Col0, Ll, M, TInd, Ind, last_depth(Es, LD), W),
[ES | pp_tail(Es, Col0, Col0 + WE, Ll, M, TInd, Ind, LD, S, W + WE)].
pp_tail([], _Col0, _Col, _Ll, _M, _TInd, _Ind, _LD, _S, _W) ->
"";
pp_tail([{_, Len}=E | Es], Col0, Col, Ll, M, TInd, Ind, LD, S, W) ->
LD1 = last_depth(Es, LD),
ELen = 1 + Len,
if
LD1 =:= 0, ELen + 1 < Ll - Col, W + ELen + 1 =< M, ?ATM(E);
LD1 > 0, ELen < Ll - Col - LD1, W + ELen + LD1 =< M, ?ATM(E) ->
[$,, write(E) |
pp_tail(Es, Col0, Col + ELen, Ll, M, TInd, Ind, LD, S, W+ELen)];
true ->
{ES, WE} = pp_element(E, Col0, Ll, M, TInd, Ind, LD1, 0),
[$,, $\n, Ind, ES |
pp_tail(Es, Col0, Col0 + WE, Ll, M, TInd, Ind, LD, S, WE)]
end;
pp_tail({dots, _}, _Col0, _Col, _Ll, _M, _TInd, _Ind, _LD, S, _W) ->
[S | "..."];
pp_tail({_, Len}=E, _Col0, Col, Ll, M, _TInd, _Ind, LD, S, W)
when Len + 1 < Ll - Col - (LD + 1),
Len + 1 + W + (LD + 1) =< M,
?ATM(E) ->
[S | write(E)];
pp_tail(E, Col0, _Col, Ll, M, TInd, Ind, LD, S, _W) ->
[S, $\n, Ind | pp(E, Col0, Ll, M, TInd, Ind, LD + 1, 0)].
pp_element({_, Len}=E, Col, Ll, M, _TInd, _Ind, LD, W)
when Len < Ll - Col - LD, Len + W + LD =< M, ?ATM(E) ->
{write(E), Len};
pp_element(E, Col, Ll, M, TInd, Ind, LD, W) ->
{pp(E, Col, Ll, M, TInd, Ind, LD, W), Ll}. % force nl
%% Reuse the list created by io_lib:write_binary()...
pp_binary([LT,LT,S,GT,GT], Col, Ll, M, Ind, LD, W) ->
N = erlang:max(8, erlang:min(Ll - Col, M - 4 - W) - LD),
[LT,LT,pp_binary(S, N, N, Ind),GT,GT].
pp_binary([BS, $, | S], N, N0, Ind) ->
Len = length(BS) + 1,
case N - Len of
N1 when N1 < 0 ->
[$\n, Ind, BS, $, | pp_binary(S, N0 - Len, N0, Ind)];
N1 ->
[BS, $, | pp_binary(S, N1, N0, Ind)]
end;
pp_binary([BS1, $:, BS2]=S, N, _N0, Ind)
when length(BS1) + length(BS2) + 1 > N ->
[$\n, Ind, S];
pp_binary(S, N, _N0, Ind) ->
case iolist_size(S) > N of
true ->
[$\n, Ind, S];
false ->
S
end.
write({{tuple, _IsTagged, L}, _}) ->
[${, write_list(L, $,), $}];
write({{list, L}, _}) ->
[$[, write_list(L, $|), $]];
write({{map, Pairs}, _}) ->
[$#,${, write_list(Pairs, $,), $}];
write({{map_pair, _K, _V}, _}=Pair) ->
write_pair(Pair);
write({{record, [{Name,_} | L]}, _}) ->
[Name, ${, write_fields(L), $}];
write({{bin, S}, _}) ->
S;
write({S, _}) ->
S.
write_pair({{map_pair, K, V}, _}) ->
[write(K), " => ", write(V)].
write_fields([]) ->
"";
write_fields({dots, _}) ->
"...";
write_fields([F | Fs]) ->
[write_field(F) | write_fields_tail(Fs)].
write_fields_tail([]) ->
"";
write_fields_tail({dots, _}) ->
",...";
write_fields_tail([F | Fs]) ->
[$,, write_field(F) | write_fields_tail(Fs)].
write_field({{field, Name, _NameL, F}, _}) ->
[Name, " = " | write(F)].
write_list({dots, _}, _S) ->
"...";
write_list([E | Es], S) ->
[write(E) | write_tail(Es, S)].
write_tail([], _S) ->
[];
write_tail([E | Es], S) ->
[$,, write(E) | write_tail(Es, S)];
write_tail({dots, _}, S) ->
[S | "..."];
write_tail(E, S) ->
[S | write(E)].
%% The depth (D) is used for extracting and counting the characters to
%% print. The structure is kept so that the returned intermediate
%% format can be formatted. The separators (list, tuple, record, map) are
%% counted but need to be added later.
%% D =/= 0
print_length([], _D, _RF, _Enc, _Str) ->
{"[]", 2};
print_length({}, _D, _RF, _Enc, _Str) ->
{"{}", 2};
print_length(#{}=M, _D, _RF, _Enc, _Str) when map_size(M) =:= 0 ->
{"#{}", 3};
print_length(List, D, RF, Enc, Str) when is_list(List) ->
case Str andalso printable_list(List, D, Enc) of
true ->
S = write_string(List, Enc),
{S, length(S)};
%% Truncated lists could break some existing code.
% {true, Prefix} ->
% S = write_string(Prefix, Enc),
% {[S | "..."], 3 + length(S)};
false ->
print_length_list(List, D, RF, Enc, Str)
end;
print_length(Fun, _D, _RF, _Enc, _Str) when is_function(Fun) ->
S = io_lib:write(Fun),
{S, iolist_size(S)};
print_length(R, D, RF, Enc, Str) when is_atom(element(1, R)),
is_function(RF) ->
case RF(element(1, R), tuple_size(R) - 1) of
no ->
print_length_tuple(R, D, RF, Enc, Str);
RDefs ->
print_length_record(R, D, RF, RDefs, Enc, Str)
end;
print_length(Tuple, D, RF, Enc, Str) when is_tuple(Tuple) ->
print_length_tuple(Tuple, D, RF, Enc, Str);
print_length(Map, D, RF, Enc, Str) when is_map(Map) ->
print_length_map(Map, D, RF, Enc, Str);
print_length(<<>>, _D, _RF, _Enc, _Str) ->
{"<<>>", 4};
print_length(<<_/bitstring>>, 1, _RF, _Enc, _Str) ->
{"<<...>>", 7};
print_length(<<_/bitstring>>=Bin, D, _RF, Enc, Str) ->
case bit_size(Bin) rem 8 of
0 ->
D1 = D - 1,
case Str andalso printable_bin(Bin, D1, Enc) of
{true, List} when is_list(List) ->
S = io_lib:write_string(List, $"), %"
{[$<,$<,S,$>,$>], 4 + length(S)};
{false, List} when is_list(List) ->
S = io_lib:write_string(List, $"), %"
{[$<,$<,S,"/utf8>>"], 9 + length(S)};
{true, true, Prefix} ->
S = io_lib:write_string(Prefix, $"), %"
{[$<,$<, S | "...>>"], 7 + length(S)};
{false, true, Prefix} ->
S = io_lib:write_string(Prefix, $"), %"
{[$<,$<, S | "/utf8...>>"], 12 + length(S)};
false ->
S = io_lib:write(Bin, D),
{{bin,S}, iolist_size(S)}
end;
_ ->
S = io_lib:write(Bin, D),
{{bin,S}, iolist_size(S)}
end;
print_length(Term, _D, _RF, _Enc, _Str) ->
S = io_lib:write(Term),
{S, lists:flatlength(S)}.
print_length_map(_Map, 1, _RF, _Enc, _Str) ->
{"#{...}", 6};
print_length_map(Map, D, RF, Enc, Str) when is_map(Map) ->
Pairs = print_length_map_pairs(maps_to_list(Map, D), D, RF, Enc, Str),
{{map, Pairs}, list_length(Pairs, 3)}.
maps_to_list(Map, D) when D < 0; map_size(Map) =< D ->
maps:to_list(Map);
maps_to_list(Map, D) ->
F = fun(_K, _V, {N, L}) when N =:= D ->
throw(L);
(K, V, {N, L}) ->
{N+1, [{K, V} | L]}
end,
lists:reverse(catch maps:fold(F, {0, []}, Map)).
print_length_map_pairs([], _D, _RF, _Enc, _Str) ->
[];
print_length_map_pairs(_Pairs, 1, _RF, _Enc, _Str) ->
{dots, 3};
print_length_map_pairs([{K, V} | Pairs], D, RF, Enc, Str) ->
[print_length_map_pair(K, V, D - 1, RF, Enc, Str) |
print_length_map_pairs(Pairs, D - 1, RF, Enc, Str)].
print_length_map_pair(K, V, D, RF, Enc, Str) ->
{KS, KL} = print_length(K, D, RF, Enc, Str),
{VS, VL} = print_length(V, D, RF, Enc, Str),
KL1 = KL + 4,
{{map_pair, {KS, KL1}, {VS, VL}}, KL1 + VL}.
print_length_tuple(_Tuple, 1, _RF, _Enc, _Str) ->
{"{...}", 5};
print_length_tuple(Tuple, D, RF, Enc, Str) ->
L = print_length_list1(tuple_to_list(Tuple), D, RF, Enc, Str),
IsTagged = is_atom(element(1, Tuple)) and (tuple_size(Tuple) > 1),
{{tuple,IsTagged,L}, list_length(L, 2)}.
print_length_record(_Tuple, 1, _RF, _RDefs, _Enc, _Str) ->
{"{...}", 5};
print_length_record(Tuple, D, RF, RDefs, Enc, Str) ->
Name = [$# | io_lib:write_atom(element(1, Tuple))],
NameL = length(Name),
Elements = tl(tuple_to_list(Tuple)),
L = print_length_fields(RDefs, D - 1, Elements, RF, Enc, Str),
{{record, [{Name,NameL} | L]}, list_length(L, NameL + 2)}.
print_length_fields([], _D, [], _RF, _Enc, _Str) ->
[];
print_length_fields(_, 1, _, _RF, _Enc, _Str) ->
{dots, 3};
print_length_fields([Def | Defs], D, [E | Es], RF, Enc, Str) ->
[print_length_field(Def, D - 1, E, RF, Enc, Str) |
print_length_fields(Defs, D - 1, Es, RF, Enc, Str)].
print_length_field(Def, D, E, RF, Enc, Str) ->
Name = io_lib:write_atom(Def),
{S, L} = print_length(E, D, RF, Enc, Str),
NameL = length(Name) + 3,
{{field, Name, NameL, {S, L}}, NameL + L}.
print_length_list(List, D, RF, Enc, Str) ->
L = print_length_list1(List, D, RF, Enc, Str),
{{list, L}, list_length(L, 2)}.
print_length_list1([], _D, _RF, _Enc, _Str) ->
[];
print_length_list1(_, 1, _RF, _Enc, _Str) ->
{dots, 3};
print_length_list1([E | Es], D, RF, Enc, Str) ->
[print_length(E, D - 1, RF, Enc, Str) |
print_length_list1(Es, D - 1, RF, Enc, Str)];
print_length_list1(E, D, RF, Enc, Str) ->
print_length(E, D - 1, RF, Enc, Str).
list_length([], Acc) ->
Acc;
list_length([{_, Len} | Es], Acc) ->
list_length_tail(Es, Acc + Len);
list_length({_, Len}, Acc) ->
Acc + Len.
list_length_tail([], Acc) ->
Acc;
list_length_tail([{_,Len} | Es], Acc) ->
list_length_tail(Es, Acc + 1 + Len);
list_length_tail({_, Len}, Acc) ->
Acc + 1 + Len.
%% ?CHARS printable characters has depth 1.
-define(CHARS, 4).
printable_list(_L, 1, _Enc) ->
false;
printable_list(L, _D, latin1) ->
io_lib:printable_latin1_list(L);
printable_list(L, _D, _Uni) ->
io_lib:printable_list(L).
printable_bin(Bin, D, Enc) when D >= 0, ?CHARS * D =< byte_size(Bin) ->
printable_bin(Bin, erlang:min(?CHARS * D, byte_size(Bin)), D, Enc);
printable_bin(Bin, D, Enc) ->
printable_bin(Bin, byte_size(Bin), D, Enc).
printable_bin(Bin, Len, D, latin1) ->
N = erlang:min(20, Len),
L = binary_to_list(Bin, 1, N),
case printable_latin1_list(L, N) of
all when N =:= byte_size(Bin) ->
{true, L};
all when N =:= Len -> % N < byte_size(Bin)
{true, true, L};
all ->
case printable_bin1(Bin, 1 + N, Len - N) of
0 when byte_size(Bin) =:= Len ->
{true, binary_to_list(Bin)};
NC when D > 0, Len - NC >= D ->
{true, true, binary_to_list(Bin, 1, Len - NC)};
NC when is_integer(NC) ->
false
end;
NC when is_integer(NC), D > 0, N - NC >= D ->
{true, true, binary_to_list(Bin, 1, N - NC)};
NC when is_integer(NC) ->
false
end;
printable_bin(Bin, Len, D, _Uni) ->
case valid_utf8(Bin,Len) of
true ->
case printable_unicode(Bin, Len, [], io:printable_range()) of
{_, <<>>, L} ->
{byte_size(Bin) =:= length(L), L};
{NC, Bin1, L} when D > 0, Len - NC >= D ->
{byte_size(Bin)-byte_size(Bin1) =:= length(L), true, L};
{_NC, _Bin, _L} ->
false
end;
false ->
printable_bin(Bin, Len, D, latin1)
end.
printable_bin1(_Bin, _Start, 0) ->
0;
printable_bin1(Bin, Start, Len) ->
N = erlang:min(10000, Len),
L = binary_to_list(Bin, Start, Start + N - 1),
case printable_latin1_list(L, N) of
all ->
printable_bin1(Bin, Start + N, Len - N);
NC when is_integer(NC) ->
Len - (N - NC)
end.
%% -> all | integer() >=0. Adopted from io_lib.erl.
% printable_latin1_list([_ | _], 0) -> 0;
printable_latin1_list([C | Cs], N) when C >= $\s, C =< $~ ->
printable_latin1_list(Cs, N - 1);
printable_latin1_list([C | Cs], N) when C >= $\240, C =< $\377 ->
printable_latin1_list(Cs, N - 1);
printable_latin1_list([$\n | Cs], N) -> printable_latin1_list(Cs, N - 1);
printable_latin1_list([$\r | Cs], N) -> printable_latin1_list(Cs, N - 1);
printable_latin1_list([$\t | Cs], N) -> printable_latin1_list(Cs, N - 1);
printable_latin1_list([$\v | Cs], N) -> printable_latin1_list(Cs, N - 1);
printable_latin1_list([$\b | Cs], N) -> printable_latin1_list(Cs, N - 1);
printable_latin1_list([$\f | Cs], N) -> printable_latin1_list(Cs, N - 1);
printable_latin1_list([$\e | Cs], N) -> printable_latin1_list(Cs, N - 1);
printable_latin1_list([], _) -> all;
printable_latin1_list(_, N) -> N.
valid_utf8(<<>>,_) ->
true;
valid_utf8(_,0) ->
true;
valid_utf8(<<_/utf8, R/binary>>,N) ->
valid_utf8(R,N-1);
valid_utf8(_,_) ->
false.
printable_unicode(<<C/utf8, R/binary>>=Bin, I, L, Range) when I > 0 ->
case printable_char(C,Range) of
true ->
printable_unicode(R, I - 1, [C | L],Range);
false ->
{I, Bin, lists:reverse(L)}
end;
printable_unicode(Bin, I, L,_) ->
{I, Bin, lists:reverse(L)}.
printable_char($\n,_) -> true;
printable_char($\r,_) -> true;
printable_char($\t,_) -> true;
printable_char($\v,_) -> true;
printable_char($\b,_) -> true;
printable_char($\f,_) -> true;
printable_char($\e,_) -> true;
printable_char(C,latin1) ->
C >= $\s andalso C =< $~ orelse
C >= 16#A0 andalso C =< 16#FF;
printable_char(C,unicode) ->
C >= $\s andalso C =< $~ orelse
C >= 16#A0 andalso C < 16#D800 orelse
C > 16#DFFF andalso C < 16#FFFE orelse
C > 16#FFFF andalso C =< 16#10FFFF.
write_string(S, latin1) ->
io_lib:write_latin1_string(S, $"); %"
write_string(S, _Uni) ->
io_lib:write_string(S, $"). %"
%% Throw 'no_good' if the indentation exceeds half the line length
%% unless there is room for M characters on the line.
cind({_S, Len}, Col, Ll, M, Ind, LD, W) when Len < Ll - Col - LD,
Len + W + LD =< M ->
Ind;
cind({{list,L}, _Len}, Col, Ll, M, Ind, LD, W) ->
cind_list(L, Col + 1, Ll, M, Ind, LD, W + 1);
cind({{tuple,true,L}, _Len}, Col, Ll, M, Ind, LD, W) ->
cind_tag_tuple(L, Col, Ll, M, Ind, LD, W + 1);
cind({{tuple,false,L}, _Len}, Col, Ll, M, Ind, LD, W) ->
cind_list(L, Col + 1, Ll, M, Ind, LD, W + 1);
cind({{map,Pairs},_Len}, Col, Ll, M, Ind, LD, W) ->
cind_map(Pairs, Col + 2, Ll, M, Ind, LD, W + 2);
cind({{record,[{_Name,NLen} | L]}, _Len}, Col, Ll, M, Ind, LD, W) ->
cind_record(L, NLen, Col, Ll, M, Ind, LD, W + NLen + 1);
cind({{bin,_S}, _Len}, _Col, _Ll, _M, Ind, _LD, _W) ->
Ind;
cind({_S, _Len}, _Col, _Ll, _M, Ind, _LD, _W) ->
Ind.
cind_tag_tuple([{_Tag,Tlen} | L], Col, Ll, M, Ind, LD, W) ->
TagInd = Tlen + 2,
Tcol = Col + TagInd,
if
Ind > 0, TagInd > Ind ->
Col1 = Col + Ind,
if
M + Col1 =< Ll; Col1 =< Ll div 2 ->
cind_tail(L, Col1, Tcol, Ll, M, Ind, LD, W + Tlen);
true ->
throw(no_good)
end;
M + Tcol < Ll; Tcol < Ll div 2 ->
cind_list(L, Tcol, Ll, M, Ind, LD, W + Tlen + 1);
true ->
throw(no_good)
end.
cind_map([P | Ps], Col, Ll, M, Ind, LD, W) ->
PW = cind_pair(P, Col, Ll, M, Ind, last_depth(Ps, LD), W),
cind_pairs_tail(Ps, Col, Col + PW, Ll, M, Ind, LD, W + PW);
cind_map(_, _Col, _Ll, _M, Ind, _LD, _W) ->
Ind.
cind_pairs_tail([{_, Len}=P | Ps], Col0, Col, Ll, M, Ind, LD, W) ->
LD1 = last_depth(Ps, LD),
ELen = 1 + Len,
if
LD1 =:= 0, ELen + 1 < Ll - Col, W + ELen + 1 =< M, ?ATM_PAIR(P);
LD1 > 0, ELen < Ll - Col - LD1, W + ELen + LD1 =< M, ?ATM_PAIR(P) ->
cind_pairs_tail(Ps, Col0, Col + ELen, Ll, M, Ind, LD, W + ELen);
true ->
PW = cind_pair(P, Col0, Ll, M, Ind, LD1, 0),
cind_pairs_tail(Ps, Col0, Col0 + PW, Ll, M, Ind, LD, PW)
end;
cind_pairs_tail(_, _Col0, _Col, _Ll, _M, Ind, _LD, _W) ->
Ind.
cind_pair({{map_pair, _Key, _Value}, Len}=Pair, Col, Ll, M, _Ind, LD, W)
when Len < Ll - Col - LD, Len + W + LD =< M ->
if
?ATM_PAIR(Pair) ->
Len;
true ->
Ll
end;
cind_pair({{map_pair, K, V}, _Len}, Col0, Ll, M, Ind, LD, W0) ->
cind(K, Col0, Ll, M, Ind, LD, W0),
I = map_value_indent(Ind),
cind(V, Col0 + I, Ll, M, Ind, LD, 0),
Ll.
map_value_indent(TInd) ->
case TInd > 0 of
true ->
TInd;
false ->
4
end.
cind_record([F | Fs], Nlen, Col0, Ll, M, Ind, LD, W0) ->
Nind = Nlen + 1,
{Col, W} = cind_rec(Nind, Col0, Ll, M, Ind, W0),
FW = cind_field(F, Col, Ll, M, Ind, last_depth(Fs, LD), W),
cind_fields_tail(Fs, Col, Col + FW, Ll, M, Ind, LD, W + FW);
cind_record(_, _Nlen, _Col, _Ll, _M, Ind, _LD, _W) ->
Ind.
cind_fields_tail([{_, Len}=F | Fs], Col0, Col, Ll, M, Ind, LD, W) ->
LD1 = last_depth(Fs, LD),
ELen = 1 + Len,
if
LD1 =:= 0, ELen + 1 < Ll - Col, W + ELen + 1 =< M, ?ATM_FLD(F);
LD1 > 0, ELen < Ll - Col - LD1, W + ELen + LD1 =< M, ?ATM_FLD(F) ->
cind_fields_tail(Fs, Col0, Col + ELen, Ll, M, Ind, LD, W + ELen);
true ->
FW = cind_field(F, Col0, Ll, M, Ind, LD1, 0),
cind_fields_tail(Fs, Col0, Col + FW, Ll, M, Ind, LD, FW)
end;
cind_fields_tail(_, _Col0, _Col, _Ll, _M, Ind, _LD, _W) ->
Ind.
cind_field({{field, _N, _NL, _F}, Len}=Fl, Col, Ll, M, _Ind, LD, W)
when Len < Ll - Col - LD, Len + W + LD =< M ->
if
?ATM_FLD(Fl) ->
Len;
true ->
Ll
end;
cind_field({{field, _Name, NameL, F}, _Len}, Col0, Ll, M, Ind, LD, W0) ->
{Col, W} = cind_rec(NameL, Col0, Ll, M, Ind, W0 + NameL),
cind(F, Col, Ll, M, Ind, LD, W),
Ll.
cind_rec(RInd, Col0, Ll, M, Ind, W0) ->
Nl = (Ind > 0) and (RInd > Ind),
DCol = case Nl of
true -> Ind;
false -> RInd
end,
Col = Col0 + DCol,
if
M + Col =< Ll; Col =< Ll div 2 ->
W = case Nl of
true -> 0;
false -> W0
end,
{Col, W};
true ->
throw(no_good)
end.
cind_list({dots, _}, _Col0, _Ll, _M, Ind, _LD, _W) ->
Ind;
cind_list([E | Es], Col0, Ll, M, Ind, LD, W) ->
WE = cind_element(E, Col0, Ll, M, Ind, last_depth(Es, LD), W),
cind_tail(Es, Col0, Col0 + WE, Ll, M, Ind, LD, W + WE).
cind_tail([], _Col0, _Col, _Ll, _M, Ind, _LD, _W) ->
Ind;
cind_tail([{_, Len}=E | Es], Col0, Col, Ll, M, Ind, LD, W) ->
LD1 = last_depth(Es, LD),
ELen = 1 + Len,
if
LD1 =:= 0, ELen + 1 < Ll - Col, W + ELen + 1 =< M, ?ATM(E);
LD1 > 0, ELen < Ll - Col - LD1, W + ELen + LD1 =< M, ?ATM(E) ->
cind_tail(Es, Col0, Col + ELen, Ll, M, Ind, LD, W + ELen);
true ->
WE = cind_element(E, Col0, Ll, M, Ind, LD1, 0),
cind_tail(Es, Col0, Col0 + WE, Ll, M, Ind, LD, WE)
end;
cind_tail({dots, _}, _Col0, _Col, _Ll, _M, Ind, _LD, _W) ->
Ind;
cind_tail({_, Len}=E, _Col0, Col, Ll, M, Ind, LD, W)
when Len + 1 < Ll - Col - (LD + 1),
Len + 1 + W + (LD + 1) =< M,
?ATM(E) ->
Ind;
cind_tail(E, _Col0, Col, Ll, M, Ind, LD, _W) ->
cind(E, Col, Ll, M, Ind, LD + 1, 0).
cind_element({_, Len}=E, Col, Ll, M, _Ind, LD, W)
when Len < Ll - Col - LD, Len + W + LD =< M, ?ATM(E) ->
Len;
cind_element(E, Col, Ll, M, Ind, LD, W) ->
cind(E, Col, Ll, M, Ind, LD, W),
Ll.
last_depth([_ | _], _LD) ->
0;
last_depth(_, LD) ->
LD + 1.
while_fail([], _F, V) ->
V;
while_fail([A | As], F, V) ->
try F(A) catch _ -> while_fail(As, F, V) end.
indent(N) when is_integer(N), N > 0 ->
chars($\s, N-1).
indent(1, Ind) -> % Optimization of common case
[$\s | Ind];
indent(4, Ind) -> % Optimization of common case
S2 = [$\s, $\s],
[S2, S2 | Ind];
indent(N, Ind) when is_integer(N), N > 0 ->
[chars($\s, N) | Ind].
%% A deep version of string:chars/2
chars(_C, 0) ->
[];
chars(C, 2) ->
[C, C];
chars(C, 3) ->
[C, C, C];
chars(C, N) when (N band 1) =:= 0 ->
S = chars(C, N bsr 1),
[S | S];
chars(C, N) ->
S = chars(C, N bsr 1),
[C, S | S].
get_option(Key, TupleList, Default) ->
case lists:keyfind(Key, 1, TupleList) of
false -> Default;
{Key, Value} -> Value;
_ -> Default
end.
