You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
48 lines
1.2 KiB
48 lines
1.2 KiB
/*
|
|
* Copyright 2019 The Android Open Source Project
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
#include <array>
|
|
|
|
/* Helper class generating N unique ids, from 0 to N-1 */
|
|
template <std::size_t N>
|
|
class IdGenerator {
|
|
public:
|
|
static int ALL_USED;
|
|
|
|
IdGenerator() : in_use_{} {}
|
|
|
|
/* Returns next free id, or ALL_USED if no ids left */
|
|
int GetNext() {
|
|
for (std::size_t i = 0; i < N; i++) {
|
|
if (!in_use_[i]) {
|
|
in_use_[i] = true;
|
|
return i;
|
|
}
|
|
}
|
|
return ALL_USED;
|
|
}
|
|
|
|
/* Release given ID */
|
|
void Release(int id) { in_use_[id] = false; }
|
|
|
|
private:
|
|
std::array<bool, N> in_use_;
|
|
};
|
|
|
|
template <std::size_t N>
|
|
int IdGenerator<N>::ALL_USED = -1; |