| % 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(hqueue). |
| |
| |
| -on_load(init/0). |
| |
| |
| -export([ |
| new/0, |
| new/1, |
| |
| extract_max/1, |
| insert/3, |
| |
| from_list/1, |
| from_list/2, |
| to_list/1, |
| |
| heap_size/1, |
| info/1, |
| is_empty/1, |
| max_elems/1, |
| size/1, |
| |
| resize_heap/2, |
| scale_by/2, |
| set_max_elems/2 |
| ]). |
| |
| |
| -define(NOT_LOADED, not_loaded(?LINE)). |
| |
| |
| -type hqueue() :: term(). |
| -type hqueue_priority() :: float(). %% this should be non_neg_float() |
| -type hqueue_val() :: term(). |
| -type hqueue_elem() :: {hqueue_priority(), hqueue_val()}. |
| -type hqueue_option() :: {max_elems, pos_integer()} |
| | {heap_size, pos_integer()}. |
| -type hqueue_stat() :: {max_elems, pos_integer()} |
| | {heap_size, pos_integer()} |
| | {size, non_neg_integer()}. |
| |
| -export_type([hqueue/0]). |
| |
| |
| -spec new() -> {ok, hqueue()}. |
| new() -> |
| new([]). |
| |
| |
| -spec new([hqueue_option()]) -> {ok, hqueue()}. |
| new(_Options) -> |
| ?NOT_LOADED. |
| |
| |
| %% Extraction order is undefined for entries with duplicate priorities |
| -spec extract_max(hqueue()) -> hqueue_elem() | {error, empty}. |
| extract_max(_HQ) -> |
| ?NOT_LOADED. |
| |
| |
| -spec insert(hqueue(), hqueue_priority(), hqueue_val()) -> ok | {error, full}. |
| insert(_HQ, _Priority, _Val) -> |
| ?NOT_LOADED. |
| |
| |
| -spec size(hqueue()) -> integer(). |
| size(_HQ) -> |
| ?NOT_LOADED. |
| |
| |
| -spec max_elems(hqueue()) -> integer(). |
| max_elems(_HQ) -> |
| ?NOT_LOADED. |
| |
| |
| %% Returns old max elems or error if NewMaxElems < size(HQ) |
| -spec set_max_elems(hqueue(), pos_integer()) -> pos_integer() |
| | {error, too_small}. |
| set_max_elems(_HQ, _NewMaxElems) -> |
| ?NOT_LOADED. |
| |
| |
| -spec is_empty(hqueue()) -> boolean(). |
| is_empty(HQ) -> |
| hqueue:size(HQ) =:= 0. |
| |
| |
| -spec to_list(hqueue()) -> [hqueue_elem()]. |
| to_list(_HQ) -> |
| ?NOT_LOADED. |
| |
| |
| -spec from_list([hqueue_elem()]) -> {ok, hqueue()}. |
| from_list(Elems) -> |
| from_list(Elems, []). |
| |
| |
| -spec from_list([hqueue_elem()], [hqueue_option()]) -> {ok, hqueue()}. |
| from_list(Elems, Options) -> |
| {ok, HQ} = ?MODULE:new(Options), |
| lists:foreach(fun({Priority, Val}) -> |
| ?MODULE:insert(HQ, Priority, Val) |
| end, Elems), |
| {ok, HQ}. |
| |
| |
| -spec scale_by(hqueue(), float()) -> ok. |
| scale_by(_HQ, _Factor) -> |
| ?NOT_LOADED. |
| |
| |
| %% Returns old heap size or error if NewHeapSize < size(HQ) |
| -spec resize_heap(hqueue(), pos_integer()) -> pos_integer() |
| | {error, too_small}. |
| resize_heap(_HQ, _NewHeapSize) -> |
| ?NOT_LOADED. |
| |
| |
| -spec heap_size(hqueue()) -> pos_integer(). |
| heap_size(_HQ) -> |
| ?NOT_LOADED. |
| |
| |
| -spec info(hqueue()) -> [hqueue_stat()]. |
| info(HQ) -> |
| [ |
| {heap_size, hqueue:heap_size(HQ)}, |
| {max_elems, hqueue:max_elems(HQ)}, |
| {size, hqueue:size(HQ)} |
| ]. |
| |
| |
| |
| 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, "hqueue"), 0). |
| |
| |
| not_loaded(Line) -> |
| erlang:nif_error({not_loaded, [{module, ?MODULE}, {line, Line}]}). |