%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 1998-2010. 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(tv_io_lib_format).
-export([fwrite/2,fwrite_g/1,indentation/2]).
%% fwrite(Format, ArgList) -> [Char].
%% Format the arguments in ArgList after string Format. Just generate
%% an error if there is an error in the arguments.
%%
%% To do the printing command correctly we need to calculate the
%% current indentation for everything before it. This may be very
%% expensive, especially when it is not needed, so we first determine
%% if, and for how long, we need to calculate the indentations. We do
%% this by first collecting all the control sequences and
%% corresponding arguments, then counting the print sequences and
%% then building the output. This method has some drawbacks, it does
%% two passes over the format string and creates more temporary data,
%% and it also splits the handling of the control characters into two
%% parts.
fwrite(Format, Args) when is_atom(Format) ->
fwrite(atom_to_list(Format), Args);
fwrite(Format, Args) ->
Cs = collect(Format, Args),
Pc = pcount(Cs),
build(Cs, Pc, 0).
collect([$~|Fmt0], Args0) ->
{C,Fmt1,Args1} = collect_cseq(Fmt0, Args0),
[C|collect(Fmt1, Args1)];
collect([C|Fmt], Args) ->
[C|collect(Fmt, Args)];
collect([], []) -> [].
collect_cseq(Fmt0, Args0) ->
{F,Ad,Fmt1,Args1} = field_width(Fmt0, Args0),
{P,Fmt2,Args2} = precision(Fmt1, Args1),
{Pad,Fmt3,Args3} = pad_char(Fmt2, Args2),
{C,As,Fmt4,Args4} = collect_cc(Fmt3, Args3),
{{C,As,F,Ad,P,Pad},Fmt4,Args4}.
field_width([$-|Fmt0], Args0) ->
{F,Fmt,Args} = field_value(Fmt0, Args0),
field_width(-F, Fmt, Args);
field_width(Fmt0, Args0) ->
{F,Fmt,Args} = field_value(Fmt0, Args0),
field_width(F, Fmt, Args).
field_width(F, Fmt, Args) when F < 0 ->
{-F,left,Fmt,Args};
field_width(F, Fmt, Args) when F >= 0 ->
{F,right,Fmt,Args}.
precision([$.|Fmt], Args) ->
field_value(Fmt, Args);
precision(Fmt, Args) ->
{none,Fmt,Args}.
field_value([$*|Fmt], [A|Args]) when is_integer(A) ->
{A,Fmt,Args};
field_value([C|Fmt], Args) when C >= $0, C =< $9 ->
field_value([C|Fmt], Args, 0);
field_value(Fmt, Args) ->
{none,Fmt,Args}.
field_value([C|Fmt], Args, F) when C >= $0, C =< $9 ->
field_value(Fmt, Args, 10*F + (C - $0));
field_value(Fmt, Args, F) -> %Default case
{F,Fmt,Args}.
pad_char([$.,$*|Fmt], [Pad|Args]) -> {Pad,Fmt,Args};
pad_char([$.,Pad|Fmt], Args) -> {Pad,Fmt,Args};
pad_char(Fmt, Args) -> {$ ,Fmt,Args}.
%% collect_cc([FormatChar], [Argument]) ->
%% {Control,[ControlArg],[FormatChar],[Arg]}.
%% Here we collect the argments for each control character.
%% Be explicit to cause failure early.
collect_cc([$w|Fmt], [A|Args]) -> {$w,[A],Fmt,Args};
collect_cc([$p|Fmt], [A|Args]) -> {$p,[A],Fmt,Args};
collect_cc([$W|Fmt], [A,Depth|Args]) -> {$W,[A,Depth],Fmt,Args};
collect_cc([$P|Fmt], [A,Depth|Args]) -> {$P,[A,Depth],Fmt,Args};
collect_cc([$s|Fmt], [A|Args]) -> {$s,[A],Fmt,Args};
collect_cc([$e|Fmt], [A|Args]) -> {$e,[A],Fmt,Args};
collect_cc([$f|Fmt], [A|Args]) -> {$f,[A],Fmt,Args};
collect_cc([$g|Fmt], [A|Args]) -> {$g,[A],Fmt,Args};
collect_cc([$c|Fmt], [A|Args]) -> {$c,[A],Fmt,Args};
collect_cc([$~|Fmt], Args) -> {$~,[],Fmt,Args};
collect_cc([$n|Fmt], Args) -> {$n,[],Fmt,Args};
collect_cc([$i|Fmt], [A|Args]) -> {$i,[A],Fmt,Args}.
%% pcount([ControlC]) -> Count.
%% Count the number of print requests.
pcount(Cs) -> pcount(Cs, 0).
pcount([{$p,_As,_F,_Ad,_P,_Pad}|Cs], Acc) -> pcount(Cs, Acc+1);
pcount([{$P,_As,_F,_Ad,_P,_Pad}|Cs], Acc) -> pcount(Cs, Acc+1);
pcount([_|Cs], Acc) -> pcount(Cs, Acc);
pcount([], Acc) -> Acc.
%% build([Control], Pc, Indentation) -> [Char].
%% Interpret the control structures. Count the number of print
%% remaining and only calculate indentation when necessary. Must also
%% be smart when calculating indentation for characters in format.
build([{C,As,F,Ad,P,Pad}|Cs], Pc0, I) ->
S = control(C, As, F, Ad, P, Pad, I),
Pc1 = decr_pc(C, Pc0),
if
Pc1 > 0 -> [S|build(Cs, Pc1, indentation(S, I))];
true -> [S|build(Cs, Pc1, I)]
end;
build([$\n|Cs], Pc, _I) -> [$\n|build(Cs, Pc, 0)];
build([$\t|Cs], Pc, I) -> [$\t|build(Cs, Pc, ((I + 8) div 8) * 8)];
build([C|Cs], Pc, I) -> [C|build(Cs, Pc, I+1)];
build([], _, _) -> [].
decr_pc($p, Pc) -> Pc - 1;
decr_pc($P, Pc) -> Pc - 1;
decr_pc(_C, Pc) -> Pc.
%% control(FormatChar, [Argument], FieldWidth, Adjust, Precision, PadChar,
%% Indentation) ->
%% [Char]
%% This is the main dispatch function for the various formatting commands.
%% Field widths and precisions have already been calculated.
control($w, [A], F, Adj, P, Pad, _I) ->
term(tv_io_lib:write(A, -1), F, Adj, P, Pad);
control($p, [A], F, Adj, P, Pad, I) ->
print(A, -1, F, Adj, P, Pad, I);
control($W, [A,Depth], F, Adj, P, Pad, _I) when is_integer(Depth) ->
term(tv_io_lib:write(A, Depth), F, Adj, P, Pad);
control($P, [A,Depth], F, Adj, P, Pad, I) when is_integer(Depth) ->
print(A, Depth, F, Adj, P, Pad, I);
control($s, [A], F, Adj, P, Pad, _I) when is_atom(A) ->
string(atom_to_list(A), F, Adj, P, Pad);
control($s, [L], F, Adj, P, Pad, _I) ->
true = tv_io_lib:deep_char_list(L), %Check if L a character list
string(L, F, Adj, P, Pad);
control($e, [A], F, Adj, P, Pad, _I) when is_float(A) ->
fwrite_e(A, F, Adj, P, Pad);
control($f, [A], F, Adj, P, Pad, _I) when is_float(A) ->
fwrite_f(A, F, Adj, P, Pad);
control($g, [A], F, Adj, P, Pad, _I) when is_float(A) ->
fwrite_g(A, F, Adj, P, Pad);
control($c, [A], F, Adj, P, Pad, _I) when is_integer(A) ->
char(A band 255, F, Adj, P, Pad);
control($~, [], F, Adj, P, Pad, _I) -> char($~, F, Adj, P, Pad);
control($n, [], F, Adj, P, Pad, _I) -> newline(F, Adj, P, Pad);
control($i, [_A], _F, _Adj, _P, _Pad, _I) -> [].
%% indentation([Char], Indentation) -> Indentation.
%% Calculate the indentation of the end of a string given its start
%% indentation. We assume tabs at 8 cols.
indentation([$\n|Cs], _I) -> indentation(Cs, 0);
indentation([$\t|Cs], I) -> indentation(Cs, ((I + 8) div 8) * 8);
indentation([C|Cs], I) when is_integer(C) ->
indentation(Cs, I+1);
indentation([C|Cs], I) ->
indentation(Cs, indentation(C, I));
indentation([], I) -> I.
%% term(TermList, Field, Adjust, Precision, PadChar)
%% Output the characters in a term.
term(T, none, _Adj, none, _Pad) -> T;
term(T, none, Adj, P, Pad) -> term(T, P, Adj, P, Pad);
term(T, F, Adj, none, Pad) -> term(T, F, Adj, erlang:min(flat_length(T), F), Pad);
term(T, F, Adj, P, Pad) when F >= P ->
adjust_error(T, F, Adj, P, Pad).
%% print(Term, Depth, Field, Adjust, Precision, PadChar, Indentation)
%% Print a term.
print(T, D, none, Adj, P, Pad, I) -> print(T, D, 80, Adj, P, Pad, I);
print(T, D, F, Adj, none, Pad, I) -> print(T, D, F, Adj, I+1, Pad, I);
print(T, D, F, right, P, _Pad, _I) ->
tv_io_lib_pretty:pretty_print(T, P, F, D).
%% fwrite_e(Float, Field, Adjust, Precision, PadChar)
fwrite_e(Fl, none, Adj, none, Pad) -> %Default values
fwrite_e(Fl, none, Adj, 6, Pad);
fwrite_e(Fl, none, _Adj, P, _Pad) when P >= 2 ->
float_e(Fl, float_data(Fl), P);
fwrite_e(Fl, F, Adj, none, Pad) ->
fwrite_e(Fl, F, Adj, 6, Pad);
fwrite_e(Fl, F, Adj, P, Pad) when P >= 2 ->
adjust_error(float_e(Fl, float_data(Fl), P), F, Adj, F, Pad).
float_e(Fl, Fd, P) when Fl < 0.0 -> %Negative numbers
[$-|float_e(-Fl, Fd, P)];
float_e(_Fl, {Ds,E}, P) ->
case float_man(Ds, 1, P-1) of
{[$0|Fs],true} -> [[$1|Fs]|float_exp(E)];
{Fs,false} -> [Fs|float_exp(E-1)]
end.
%% float_man([Digit], Icount, Dcount) -> {[Chars],CarryFlag}.
%% Generate the characters in the mantissa from the digits with Icount
%% characters before the '.' and Dcount decimals. Handle carry and let
%% caller decide what to do at top.
float_man(Ds, 0, Dc) ->
{Cs,C} = float_man(Ds, Dc),
{[$.|Cs],C};
float_man([D|Ds], I, Dc) ->
case float_man(Ds, I-1, Dc) of
{Cs,true} when D =:= $9 -> {[$0|Cs],true};
{Cs,true} -> {[D+1|Cs],false};
{Cs,false} -> {[D|Cs],false}
end;
float_man([], I, Dc) -> %Pad with 0's
{string:chars($0, I, [$.|string:chars($0, Dc)]),false}.
float_man([D|_Ds], 0) when D >= $5 -> {[],true};
float_man([_|_], 0) -> {[],false};
float_man([D|Ds], Dc) ->
case float_man(Ds, Dc-1) of
{Cs,true} when D =:= $9 -> {[$0|Cs],true};
{Cs,true} -> {[D+1|Cs],false};
{Cs,false} -> {[D|Cs],false}
end;
float_man([], Dc) -> {string:chars($0, Dc),false}. %Pad with 0's
%% float_exp(Exponent) -> [Char].
%% Generate the exponent of a floating point number. Alwayd include sign.
float_exp(E) when E >= 0 ->
[$e,$+|integer_to_list(E)];
float_exp(E) ->
[$e|integer_to_list(E)].
%% fwrite_f(FloatData, Field, Adjust, Precision, PadChar)
fwrite_f(Fl, none, Adj, none, Pad) -> %Default values
fwrite_f(Fl, none, Adj, 6, Pad);
fwrite_f(Fl, none, _Adj, P, _Pad) when P >= 1 ->
float_f(Fl, float_data(Fl), P);
fwrite_f(Fl, F, Adj, none, Pad) ->
fwrite_f(Fl, F, Adj, 6, Pad);
fwrite_f(Fl, F, Adj, P, Pad) when P >= 1 ->
adjust_error(float_f(Fl, float_data(Fl), P), F, Adj, F, Pad).
float_f(Fl, Fd, P) when Fl < 0.0 ->
[$-|float_f(-Fl, Fd, P)];
float_f(Fl, {Ds,E}, P) when E =< 0 ->
float_f(Fl, {string:chars($0, -E+1, Ds),1}, P); %Prepend enough 0's
float_f(_Fl, {Ds,E}, P) ->
case float_man(Ds, E, P) of
{Fs,true} -> "1" ++ Fs; %Handle carry
{Fs,false} -> Fs
end.
%% float_data([FloatChar]) -> {[Digit],Exponent}
float_data(Fl) ->
float_data(float_to_list(Fl), []).
float_data([$e|E], Ds) ->
{reverse(Ds),list_to_integer(E)+1};
float_data([D|Cs], Ds) when D >= $0, D =< $9 ->
float_data(Cs, [D|Ds]);
float_data([_D|Cs], Ds) ->
float_data(Cs, Ds).
%% fwrite_g(Float, Field, Adjust, Precision, PadChar)
%% Use the f form if Float is > 0.1 and < 10^4, else the e form.
%% Precision always means the # of significant digits.
fwrite_g(Fl) ->
fwrite_g(Fl, none, right, none, $\s).
fwrite_g(Fl, F, Adj, none, Pad) ->
fwrite_g(Fl, F, Adj, 6, Pad);
fwrite_g(Fl, F, Adj, P, Pad) when abs(Fl) < 0.1 ->
fwrite_e(Fl, F, Adj, P, Pad);
fwrite_g(Fl, F, Adj, P, Pad) when abs(Fl) < 1.0 ->
fwrite_f(Fl, F, Adj, P, Pad);
fwrite_g(Fl, F, Adj, P, Pad) when abs(Fl) < 10.0 ->
fwrite_f(Fl, F, Adj, P-1, Pad);
fwrite_g(Fl, F, Adj, P, Pad) when abs(Fl) < 100.0 ->
fwrite_f(Fl, F, Adj, P-2, Pad);
fwrite_g(Fl, F, Adj, P, Pad) when abs(Fl) < 1000.0 ->
fwrite_f(Fl, F, Adj, P-3, Pad);
fwrite_g(Fl, F, Adj, P, Pad) when abs(Fl) < 10000.0 ->
fwrite_f(Fl, F, Adj, P-4, Pad);
fwrite_g(Fl, F, Adj, P, Pad) ->
fwrite_e(Fl, F, Adj, P, Pad).
%% string(String, Field, Adjust, Precision, PadChar)
string(S, none, _Adj, none, _Pad) -> S;
string(S, F, Adj, none, Pad) ->
string(S, F, Adj, erlang:min(flat_length(S), F), Pad);
string(S, none, _Adj, P, Pad) ->
string:left(flatten(S), P, Pad);
string(S, F, Adj, P, Pad) when F >= P ->
adjust(string:left(flatten(S), P, Pad), string:chars(Pad, F - P), Adj).
%% char(Char, Field, Adjust, Precision, PadChar) -> [Char].
char(C, none, _Adj, none, _Pad) -> [C];
char(C, F, _Adj, none, _Pad) -> string:chars(C, F);
char(C, none, _Adj, P, _Pad) -> string:chars(C, P);
char(C, F, Adj, P, Pad) when F >= P ->
adjust(string:chars(C, P), string:chars(Pad, F - P), Adj).
%% newline(Field, Adjust, Precision, PadChar) -> [Char].
newline(none, _Adj, _P, _Pad) -> "\n";
newline(F, right, _P, _Pad) -> string:chars($\n, F).
%% adjust_error([Char], Field, Adjust, Max, PadChar) -> [Char].
%% Adjust the characters within the field if length less than Max padding
%% with PadChar.
adjust_error(Cs, F, Adj, M, Pad) ->
L = flat_length(Cs),
if
L > M ->
adjust(string:chars($*, M), string:chars(Pad, F - M), Adj);
true ->
adjust(Cs, string:chars(Pad, F - L), Adj)
end.
adjust(Data, Pad, left) -> [Data,Pad];
adjust(Data, Pad, right) -> [Pad,Data].
%%
%% Utilities
%%
reverse(List) ->
reverse(List, []).
reverse([H|T], Stack) ->
reverse(T, [H|Stack]);
reverse([], Stack) -> Stack.
%% flatten(List)
%% Flatten a list.
flatten(List) -> flatten(List, []).
flatten([H|T], Cont) when is_list(H) ->
flatten(H, [T|Cont]);
flatten([H|T], Cont) ->
[H|flatten(T, Cont)];
flatten([], [H|Cont]) -> flatten(H, Cont);
flatten([], []) -> [].
%% flat_length(List)
%% Calculate the length of a list of lists.
flat_length(List) -> flat_length(List, 0).
flat_length([H|T], L) when is_list(H) ->
flat_length(H, flat_length(T, L));
flat_length([_|T], L) ->
flat_length(T, L + 1);
flat_length([], L) -> L.
