android/android-emu/android/emulation/VmLock.cpp

// Copyright 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 "android/emulation/VmLock.h"

#include "android/base/memory/LazyInstance.h"

namespace android {

static VmLock* sInstance = nullptr;

VmLock* VmLock::get() {
    // NOT thread-safe, but we don't expect multiple threads to call this
    // concurrently at init time, and the worst that can happen is to leak
    // a single instance.
    if (!sInstance) {
        sInstance = new VmLock();
    }
    return sInstance;
}

VmLock* VmLock::set(VmLock* vmLock) {
    VmLock* result = sInstance;
    sInstance = vmLock;
    return result;
}

}  // namespace android