| % 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). |