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%%% Copyright 2009 Andrew Thompson <andrew@hijacked.us>. All rights reserved.
%%%
%%% Redistribution and use in source and binary forms, with or without
%%% modification, are permitted provided that the following conditions are met:
%%%
%%% 1. Redistributions of source code must retain the above copyright notice,
%%% this list of conditions and the following disclaimer.
%%% 2. Redistributions in binary form must reproduce the above copyright
%%% notice, this list of conditions and the following disclaimer in the
%%% documentation and/or other materials provided with the distribution.
%%%
%%% THIS SOFTWARE IS PROVIDED BY THE FREEBSD PROJECT ``AS IS'' AND ANY EXPRESS OR
%%% IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
%%% MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
%%% EVENT SHALL THE FREEBSD PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
%%% INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
%%% (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
%%% LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
%%% ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
%%% (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
%%% SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
%% @doc Some functions for working with binary strings.
-module(binstr).
-export([
strchr/2,
strrchr/2,
strpos/2,
strrpos/2,
substr/2,
substr/3,
split/3,
split/2,
chomp/1,
strip/1,
strip/2,
strip/3,
to_lower/1,
to_upper/1,
all/2,
reverse/1,
reverse_str_to_bin/1,
join/2
]).
-spec strchr(Bin :: binary(), C :: char()) -> non_neg_integer().
strchr(Bin, C) when is_binary(Bin) ->
case binary:match(Bin, <<C>>) of
{Index, _Length} ->
Index + 1;
nomatch ->
0
end.
-spec strrchr(Bin :: binary(), C :: char()) -> non_neg_integer().
strrchr(Bin, C) ->
strrchr(Bin, C, byte_size(Bin)).
strrchr(Bin, C, I) ->
case Bin of
<<_X:I/binary, C, _Rest/binary>> ->
I+1;
_ when I =< 1 ->
0;
_ ->
strrchr(Bin, C, I-1)
end.
-spec strpos(Bin :: binary(), C :: binary() | list()) -> non_neg_integer().
strpos(Bin, C) when is_binary(Bin), is_list(C) ->
strpos(Bin, list_to_binary(C));
strpos(Bin, C) when is_binary(Bin) ->
case binary:match(Bin, C) of
{Index, _Length} ->
Index+1;
nomatch ->
0
end.
-spec strrpos(Bin :: binary(), C :: binary() | list()) -> non_neg_integer().
strrpos(Bin, C) ->
strrpos(Bin, C, byte_size(Bin), byte_size(C)).
strrpos(Bin, C, I, S) ->
case Bin of
<<_X:I/binary, C:S/binary, _Rest/binary>> ->
I+1;
_ when I =< 1 ->
0;
_ ->
strrpos(Bin, C, I-1, S)
end.
-spec substr(Bin :: binary(), Start :: pos_integer() | neg_integer()) -> binary().
substr(<<>>, _) ->
<<>>;
substr(Bin, Start) when Start > 0 ->
{_, B2} = split_binary(Bin, Start-1),
B2;
substr(Bin, Start) when Start < 0 ->
Size = byte_size(Bin),
{_, B2} = split_binary(Bin, Size+Start),
B2.
-spec substr(Bin :: binary(), Start :: pos_integer() | neg_integer(), Length :: pos_integer()) -> binary().
substr(<<>>, _, _) ->
<<>>;
substr(Bin, Start, Length) when Start > 0 ->
{_, B2} = split_binary(Bin, Start-1),
{B3, _} = split_binary(B2, Length),
B3;
substr(Bin, Start, Length) when Start < 0 ->
Size = byte_size(Bin),
{_, B2} = split_binary(Bin, Size+Start),
{B3, _} = split_binary(B2, Length),
B3.
-spec split(Bin :: binary(), Separator :: binary(), SplitCount :: pos_integer()) -> [binary()].
split(Bin, Separator, SplitCount) ->
split_(Bin, Separator, SplitCount, []).
split_(<<>>, _Separator, _SplitCount, Acc) ->
lists:reverse(Acc);
split_(Bin, <<>>, 1, Acc) ->
lists:reverse([Bin | Acc]);
split_(Bin, _Separator, 1, Acc) ->
lists:reverse([Bin | Acc]);
split_(Bin, <<>>, SplitCount, Acc) ->
split_(substr(Bin, 2), <<>>, SplitCount - 1, [substr(Bin, 1, 1) | Acc]);
split_(Bin, Separator, SplitCount, Acc) ->
case strpos(Bin, Separator) of
0 ->
lists:reverse([Bin | Acc]);
Index ->
Head = substr(Bin, 1, Index - 1),
Tailpresplit = substr(Bin, Index + byte_size(Separator)),
split_(Tailpresplit, Separator, SplitCount - 1, [Head | Acc])
end.
-spec split(Bin :: binary(), Separator :: binary()) -> [binary()].
split(Bin, Separator) ->
case binary:split(Bin, Separator, [global]) of
Result ->
case lists:last(Result) of
<<>> ->
lists:sublist(Result, length(Result) - 1);
_ ->
Result
end
end.
-spec chomp(Bin :: binary()) -> binary().
chomp(Bin) ->
L = byte_size(Bin),
case [binary:at(Bin, L-2), binary:at(Bin, L-1)] of
"\r\n" ->
binary:part(Bin, 0, L-2);
[_, X] when X == $\r; X == $\n ->
binary:part(Bin, 0, L-1);
_ ->
Bin
end.
-spec strip(Bin :: binary()) -> binary().
strip(Bin) ->
strip(Bin, both, $\s).
-spec strip(Bin :: binary(), Dir :: 'left' | 'right' | 'both') -> binary().
strip(Bin, Dir) ->
strip(Bin, Dir, $\s).
-spec strip(Bin :: binary(), Dir :: 'left' | 'right' | 'both', C :: non_neg_integer()) -> binary().
strip(<<>>, _, _) ->
<<>>;
strip(Bin, both, C) ->
strip(strip(Bin, left, C), right, C);
strip(<<C, _Rest/binary>> = Bin, left, C) ->
strip(substr(Bin, 2), left, C);
strip(Bin, left, _C) ->
Bin;
strip(Bin, right, C) ->
L = byte_size(Bin),
case binary:at(Bin, L-1) of
C ->
strip(binary:part(Bin, 0, L-1), right, C);
_ ->
Bin
end.
-spec to_lower(Bin :: binary()) -> binary().
to_lower(Bin) ->
to_lower(Bin, <<>>).
to_lower(<<>>, Acc) ->
Acc;
to_lower(<<H, T/binary>>, Acc) when H >= $A, H =< $Z ->
H2 = H + 32,
to_lower(T, <<Acc/binary, H2>>);
to_lower(<<H, T/binary>>, Acc) ->
to_lower(T, <<Acc/binary, H>>).
-spec to_upper(Bin :: binary()) -> binary().
to_upper(Bin) ->
to_upper(Bin, <<>>).
to_upper(<<>>, Acc) ->
Acc;
to_upper(<<H, T/binary>>, Acc) when H >= $a, H =< $z ->
H2 = H - 32,
to_upper(T, <<Acc/binary, H2>>);
to_upper(<<H, T/binary>>, Acc) ->
to_upper(T, <<Acc/binary, H>>).
-spec all(Fun :: function(), Binary :: binary()) -> boolean().
all(_Fun, <<>>) ->
true;
all(Fun, Binary) ->
Res = << <<X/integer>> || <<X>> <= Binary, Fun(X) >>,
Binary == Res.
%all(Fun, <<H, Tail/binary>>) ->
% Fun(H) =:= true andalso all(Fun, Tail).
%% this is a cool hack to very quickly reverse a binary
-spec reverse(Bin :: binary()) -> binary().
reverse(Bin) ->
Size = byte_size(Bin)*8,
<<T:Size/integer-little>> = Bin,
<<T:Size/integer-big>>.
%% reverse a string into a binary - can be faster than lists:reverse on large
%% lists, even if you run binary_to_string on the result. For smaller strings
%% it's probably slower (but still not that bad).
-spec reverse_str_to_bin(String :: string()) -> binary().
reverse_str_to_bin(String) ->
reverse(list_to_binary(String)).
-spec join(Binaries :: [binary()|list()], Glue :: binary() | list()) -> binary().
join(Binaries, Glue) ->
join(Binaries, Glue, []).
join([H], _Glue, Acc) ->
list_to_binary(lists:reverse([H | Acc]));
join([H|T], Glue, Acc) ->
join(T, Glue, [Glue, H | Acc]);
join([], _Glue, _Acc) ->
<<"">>.