-module(binref).
-export([compile_pattern/1,match/2,match/3,matches/2,matches/3,
split/2,split/3,replace/3,replace/4,first/1,last/1,at/2,
part/2,part/3,copy/1,copy/2,encode_unsigned/1,encode_unsigned/2,
decode_unsigned/1,decode_unsigned/2,referenced_byte_size/1]).
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% compile_pattern, a dummy
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
compile_pattern(Pattern) when is_binary(Pattern) ->
{[Pattern]};
compile_pattern(Pattern) ->
try
[ true = is_binary(P) || P <- Pattern ],
{Pattern}
catch
_:_ ->
erlang:error(badarg)
end.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% match and matches
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
match(H,N) ->
match(H,N,[]).
match(Haystack,Needle,Options) when is_binary(Needle) ->
match(Haystack,[Needle],Options);
match(Haystack,{Needles},Options) ->
match(Haystack,Needles,Options);
match(Haystack,Needles,Options) ->
try
true = is_binary(Haystack) and is_list(Needles), % badarg, not function_clause
case get_opts_match(Options,nomatch) of
nomatch ->
mloop(Haystack,Needles);
{A,B} when B > 0 ->
<<_:A/binary,SubStack:B/binary,_/binary>> = Haystack,
mloop(SubStack,Needles,A,B+A);
{A,B} when B < 0 ->
Start = A + B,
Len = -B,
<<_:Start/binary,SubStack:Len/binary,_/binary>> = Haystack,
mloop(SubStack,Needles,Start,Len+Start);
_ ->
nomatch
end
catch
_:_ ->
erlang:error(badarg)
end.
matches(H,N) ->
matches(H,N,[]).
matches(Haystack,Needle,Options) when is_binary(Needle) ->
matches(Haystack,[Needle],Options);
matches(Haystack,{Needles},Options) ->
matches(Haystack,Needles,Options);
matches(Haystack,Needles,Options) ->
try
true = is_binary(Haystack) and is_list(Needles), % badarg, not function_clause
case get_opts_match(Options,nomatch) of
nomatch ->
msloop(Haystack,Needles);
{A,B} when B > 0 ->
<<_:A/binary,SubStack:B/binary,_/binary>> = Haystack,
msloop(SubStack,Needles,A,B+A);
{A,B} when B < 0 ->
Start = A + B,
Len = -B,
<<_:Start/binary,SubStack:Len/binary,_/binary>> = Haystack,
msloop(SubStack,Needles,Start,Len+Start);
_ ->
[]
end
catch
_:_ ->
erlang:error(badarg)
end.
mloop(Haystack,Needles) ->
mloop(Haystack,Needles,0,byte_size(Haystack)).
mloop(_Haystack,_Needles,N,M) when N >= M ->
nomatch;
mloop(Haystack,Needles,N,M) ->
case mloop2(Haystack,Needles,N,nomatch) of
nomatch ->
% Not found
<<_:8,NewStack/binary>> = Haystack,
mloop(NewStack,Needles,N+1,M);
{N,Len} ->
{N,Len}
end.
msloop(Haystack,Needles) ->
msloop(Haystack,Needles,0,byte_size(Haystack)).
msloop(_Haystack,_Needles,N,M) when N >= M ->
[];
msloop(Haystack,Needles,N,M) ->
case mloop2(Haystack,Needles,N,nomatch) of
nomatch ->
% Not found
<<_:8,NewStack/binary>> = Haystack,
msloop(NewStack,Needles,N+1,M);
{N,Len} ->
NewN = N+Len,
if
NewN >= M ->
[{N,Len}];
true ->
<<_:Len/binary,NewStack/binary>> = Haystack,
[{N,Len} | msloop(NewStack,Needles,NewN,M)]
end
end.
mloop2(_Haystack,[],_N,Res) ->
Res;
mloop2(Haystack,[Needle|Tail],N,Candidate) ->
NS = byte_size(Needle),
case Haystack of
<<Needle:NS/binary,_/binary>> ->
NewCandidate = case Candidate of
nomatch ->
{N,NS};
{N,ONS} when ONS < NS ->
{N,NS};
Better ->
Better
end,
mloop2(Haystack,Tail,N,NewCandidate);
_ ->
mloop2(Haystack,Tail,N,Candidate)
end.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% split
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
split(H,N) ->
split(H,N,[]).
split(Haystack,{Needles},Options) ->
split(Haystack, Needles, Options);
split(Haystack,Needles0,Options) ->
try
Needles = if
is_list(Needles0) ->
Needles0;
is_binary(Needles0) ->
[Needles0];
true ->
exit(badtype)
end,
{Part,Global,Trim} = get_opts_split(Options,{nomatch,false,false}),
{Start,End,NewStack} =
case Part of
nomatch ->
{0,byte_size(Haystack),Haystack};
{A,B} when B >= 0 ->
<<_:A/binary,SubStack:B/binary,_/binary>> = Haystack,
{A,A+B,SubStack};
{A,B} when B < 0 ->
S = A + B,
L = -B,
<<_:S/binary,SubStack:L/binary,_/binary>> = Haystack,
{S,S+L,SubStack}
end,
MList = if
Global ->
msloop(NewStack,Needles,Start,End);
true ->
case mloop(NewStack,Needles,Start,End) of
nomatch ->
[];
X ->
[X]
end
end,
do_split(Haystack,MList,0,Trim)
catch
_:_ ->
erlang:error(badarg)
end.
do_split(H,[],N,true) when N >= byte_size(H) ->
[];
do_split(H,[],N,_) ->
[part(H,{N,byte_size(H)-N})];
do_split(H,[{A,B}|T],N,Trim) ->
case part(H,{N,A-N}) of
<<>> ->
Rest = do_split(H,T,A+B,Trim),
case {Trim, Rest} of
{true,[]} ->
[];
_ ->
[<<>> | Rest]
end;
Oth ->
[Oth | do_split(H,T,A+B,Trim)]
end.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% replace
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
replace(H,N,R) ->
replace(H,N,R,[]).
replace(Haystack,{Needles},Replacement,Options) ->
replace(Haystack,Needles,Replacement,Options);
replace(Haystack,Needles0,Replacement,Options) ->
try
Needles = if
is_list(Needles0) ->
Needles0;
is_binary(Needles0) ->
[Needles0];
true ->
exit(badtype)
end,
true = is_binary(Replacement), % Make badarg instead of function clause
{Part,Global,Insert} = get_opts_replace(Options,{nomatch,false,[]}),
{Start,End,NewStack} =
case Part of
nomatch ->
{0,byte_size(Haystack),Haystack};
{A,B} when B >= 0 ->
<<_:A/binary,SubStack:B/binary,_/binary>> = Haystack,
{A,A+B,SubStack};
{A,B} when B < 0 ->
S = A + B,
L = -B,
<<_:S/binary,SubStack:L/binary,_/binary>> = Haystack,
{S,S+L,SubStack}
end,
MList = if
Global ->
msloop(NewStack,Needles,Start,End);
true ->
case mloop(NewStack,Needles,Start,End) of
nomatch ->
[];
X ->
[X]
end
end,
ReplList = case Insert of
[] ->
Replacement;
Y when is_integer(Y) ->
splitat(Replacement,0,[Y]);
Li when is_list(Li) ->
splitat(Replacement,0,lists:sort(Li))
end,
erlang:iolist_to_binary(do_replace(Haystack,MList,ReplList,0))
catch
_:_ ->
erlang:error(badarg)
end.
do_replace(H,[],_,N) ->
[part(H,{N,byte_size(H)-N})];
do_replace(H,[{A,B}|T],Replacement,N) ->
[part(H,{N,A-N}),
if
is_list(Replacement) ->
do_insert(Replacement, part(H,{A,B}));
true ->
Replacement
end
| do_replace(H,T,Replacement,A+B)].
do_insert([X],_) ->
[X];
do_insert([H|T],R) ->
[H,R|do_insert(T,R)].
splitat(H,N,[]) ->
[part(H,{N,byte_size(H)-N})];
splitat(H,N,[I|T]) ->
[part(H,{N,I-N})|splitat(H,I,T)].
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% first, last and at
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
first(Subject) ->
try
<<A:8,_/binary>> = Subject,
A
catch
_:_ ->
erlang:error(badarg)
end.
last(Subject) ->
try
N = byte_size(Subject) - 1,
<<_:N/binary,A:8>> = Subject,
A
catch
_:_ ->
erlang:error(badarg)
end.
at(Subject,X) ->
try
<<_:X/binary,A:8,_/binary>> = Subject,
A
catch
_:_ ->
erlang:error(badarg)
end.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% part
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
part(Subject,Part) ->
try
do_part(Subject,Part)
catch
_:_ ->
erlang:error(badarg)
end.
part(Subject,Pos,Len) ->
part(Subject,{Pos,Len}).
do_part(Bin,{A,B}) when B >= 0 ->
<<_:A/binary,Sub:B/binary,_/binary>> = Bin,
Sub;
do_part(Bin,{A,B}) when B < 0 ->
S = A + B,
L = -B,
<<_:S/binary,Sub:L/binary,_/binary>> = Bin,
Sub.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% copy
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
copy(Subject) ->
copy(Subject,1).
copy(Subject,N) ->
try
true = is_integer(N) and (N > 0) and is_binary(Subject), % Badarg, not function clause
erlang:list_to_binary(lists:duplicate(N,Subject))
catch
_:_ ->
erlang:error(badarg)
end.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% encode_unsigned
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
encode_unsigned(Unsigned) ->
encode_unsigned(Unsigned,big).
encode_unsigned(Unsigned,Endian) ->
try
true = is_integer(Unsigned) and (Unsigned >= 0),
if
Unsigned =:= 0 ->
<<0>>;
true ->
case Endian of
big ->
list_to_binary(do_encode(Unsigned,[]));
little ->
list_to_binary(do_encode_r(Unsigned))
end
end
catch
_:_ ->
erlang:error(badarg)
end.
do_encode(0,L) ->
L;
do_encode(N,L) ->
Byte = N band 255,
NewN = N bsr 8,
do_encode(NewN,[Byte|L]).
do_encode_r(0) ->
[];
do_encode_r(N) ->
Byte = N band 255,
NewN = N bsr 8,
[Byte|do_encode_r(NewN)].
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% decode_unsigned
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
decode_unsigned(Subject) ->
decode_unsigned(Subject,big).
decode_unsigned(Subject,Endian) ->
try
true = is_binary(Subject) and (byte_size(Subject) > 0),
case Endian of
big ->
do_decode(Subject,0);
little ->
do_decode_r(Subject,0)
end
catch
_:_ ->
erlang:error(badarg)
end.
do_decode(<<>>,N) ->
N;
do_decode(<<X:8,Bin/binary>>,N) ->
do_decode(Bin,(N bsl 8) bor X).
do_decode_r(<<>>,N) ->
N;
do_decode_r(Bin,N) ->
Sz = byte_size(Bin) - 1,
<<NewBin:Sz/binary,X>> = Bin,
do_decode_r(NewBin, (N bsl 8) bor X).
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% referenced_byte_size cannot
%% be implemented in pure
%% erlang
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
referenced_byte_size(Bin) when is_binary(Bin) ->
erlang:error(not_implemented);
referenced_byte_size(_) ->
erlang:error(badarg).
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Simple helper functions
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Option "parsing"
get_opts_match([],Part) ->
Part;
get_opts_match([{scope,{A,B}} | T],_Part) ->
get_opts_match(T,{A,B});
get_opts_match(_,_) ->
throw(badopt).
get_opts_split([],{Part,Global,Trim}) ->
{Part,Global,Trim};
get_opts_split([{scope,{A,B}} | T],{_Part,Global,Trim}) ->
get_opts_split(T,{{A,B},Global,Trim});
get_opts_split([global | T],{Part,_Global,Trim}) ->
get_opts_split(T,{Part,true,Trim});
get_opts_split([trim | T],{Part,Global,_Trim}) ->
get_opts_split(T,{Part,Global,true});
get_opts_split(_,_) ->
throw(badopt).
get_opts_replace([],{Part,Global,Insert}) ->
{Part,Global,Insert};
get_opts_replace([{scope,{A,B}} | T],{_Part,Global,Insert}) ->
get_opts_replace(T,{{A,B},Global,Insert});
get_opts_replace([global | T],{Part,_Global,Insert}) ->
get_opts_replace(T,{Part,true,Insert});
get_opts_replace([{insert_replaced,N} | T],{Part,Global,_Insert}) ->
get_opts_replace(T,{Part,Global,N});
get_opts_replace(_,_) ->
throw(badopt).
