firmware/src/trylock.c

/*
 * Copyright (C) 2016 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.
 */

#include <trylock.h>
#include <atomic.h>


void trylockInit(struct TryLock *lock)
{
    lock->lock = 0;
}

void trylockRelease(struct TryLock *lock)
{
    lock->lock = 0;
}

bool trylockTryTake(struct TryLock *lock)
{
    return !atomicXchgByte(&lock->lock, 1);
}