/*******************************************************************************
 *     ___                  _   ____  ____
 *    / _ \ _   _  ___  ___| |_|  _ \| __ )
 *   | | | | | | |/ _ \/ __| __| | | |  _ \
 *   | |_| | |_| |  __/\__ \ |_| |_| | |_) |
 *    \__\_\\__,_|\___||___/\__|____/|____/
 *
 *  Copyright (c) 2014-2019 Appsicle
 *  Copyright (c) 2019-2023 QuestDB
 *
 *  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.
 *
 ******************************************************************************/

package io.questdb.mp;

import java.util.concurrent.atomic.AtomicBoolean;

// Simple, non-reentrant and unfair lock implementation.
// Don't try to use it for complex cases!
public class SimpleSpinLock {
    final AtomicBoolean lock = new AtomicBoolean(false);

    public void lock() {
        while (true) {
            //noinspection StatementWithEmptyBody
            while (lock.get()) {
                // do nothing
            }
            if (!lock.getAndSet(true)) {
                return;
            }
        }
    }

    public void unlock() {
        lock.set(false);
    }
}
