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% 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.
-module(exxhash).
-on_load(init/0).
-export([
xxhash128/1
]).
-nifs([
xxhash128_plain_nif/1,
xxhash128_dirty_nif/1
]).
% It takes about 50 usec to hash a 1MB block
-define(DIRTY_THRESHOLD, 1048576).
xxhash128(Bin) when is_binary(Bin) ->
case byte_size(Bin) =< ?DIRTY_THRESHOLD of
true ->
{H, L} = xxhash128_plain_nif(Bin),
<<H:64, L:64>>;
false ->
{H, L} = xxhash128_dirty_nif(Bin),
<<H:64, L:64>>
end.
init() ->
PrivDir =
case code:priv_dir(?MODULE) of
{error, _} ->
EbinDir = filename:dirname(code:which(?MODULE)),
AppPath = filename:dirname(EbinDir),
filename:join(AppPath, "priv");
Path ->
Path
end,
erlang:load_nif(filename:join(PrivDir, "exxhash"), 0).
xxhash128_plain_nif(_) ->
erlang:nif_error(nif_not_loaded).
xxhash128_dirty_nif(_) ->
erlang:nif_error(nif_not_loaded).
|
