Add basic tests for ashmem

    target: {

        android: {

            srcs: [

                "AshmemTest.cpp",

                "MemsetTest.cpp",

                "PropertiesTest.cpp",

                "sched_policy_test.cpp",

/*

 * 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 <sys/mman.h>

#include <cutils/ashmem.h>

#include <gtest/gtest.h>

#include <android-base/unique_fd.h>

using android::base::unique_fd;

void TestCreateRegion(size_t size, unique_fd &fd, int prot) {

    fd = unique_fd(ashmem_create_region(nullptr, size));

    ASSERT_TRUE(fd >= 0);

    ASSERT_TRUE(ashmem_valid(fd));

    ASSERT_EQ(size, static_cast<size_t>(ashmem_get_size_region(fd)));

    ASSERT_EQ(0, ashmem_set_prot_region(fd, prot));

}

void TestMmap(const unique_fd &fd, size_t size, int prot, void **region) {

    *region = mmap(nullptr, size, prot, MAP_SHARED, fd, 0);

    ASSERT_NE(MAP_FAILED, *region);

}

void TestProtDenied(const unique_fd &fd, size_t size, int prot) {

    EXPECT_EQ(MAP_FAILED, mmap(nullptr, size, prot, MAP_SHARED, fd, 0));

}

void FillData(uint8_t* data, size_t dataLen) {

    for (size_t i = 0; i < dataLen; i++) {

        data[i] = i & 0xFF;

    }

}

TEST(AshmemTest, BasicTest) {

    constexpr size_t size = PAGE_SIZE;

    uint8_t data[size];

    FillData(data, size);

    unique_fd fd;

    ASSERT_NO_FATAL_FAILURE(TestCreateRegion(size, fd, PROT_READ | PROT_WRITE));

    void *region1;

    ASSERT_NO_FATAL_FAILURE(TestMmap(fd, size, PROT_READ | PROT_WRITE, &region1));

    memcpy(region1, &data, size);

    ASSERT_EQ(0, memcmp(region1, &data, size));

    EXPECT_EQ(0, munmap(region1, size));

    void *region2;

    ASSERT_NO_FATAL_FAILURE(TestMmap(fd, size, PROT_READ, &region2));

    ASSERT_EQ(0, memcmp(region2, &data, size));

    EXPECT_EQ(0, munmap(region2, size));

}

TEST(AshmemTest, ForkTest) {

    constexpr size_t size = PAGE_SIZE;

    uint8_t data[size];

    FillData(data, size);

    unique_fd fd;

    ASSERT_NO_FATAL_FAILURE(TestCreateRegion(size, fd, PROT_READ | PROT_WRITE));

    void *region1;

    ASSERT_NO_FATAL_FAILURE(TestMmap(fd, size, PROT_READ | PROT_WRITE, &region1));

    memcpy(region1, &data, size);

    ASSERT_EQ(0, memcmp(region1, &data, size));

    EXPECT_EQ(0, munmap(region1, size));

    ASSERT_EXIT({

        void *region2 = mmap(nullptr, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);

        if (region2 == MAP_FAILED) {

            _exit(1);

        }

        if (memcmp(region2, &data, size) != 0) {

            _exit(2);

        }

        memset(region2, 0, size);

        munmap(region2, size);

        _exit(0);

    }, ::testing::ExitedWithCode(0),"");

    memset(&data, 0, size);

    void *region2;

    ASSERT_NO_FATAL_FAILURE(TestMmap(fd, size, PROT_READ | PROT_WRITE, &region2));

    ASSERT_EQ(0, memcmp(region2, &data, size));

    EXPECT_EQ(0, munmap(region2, size));

}

TEST(AshmemTest, ProtTest) {

    unique_fd fd;

    constexpr size_t size = PAGE_SIZE;

    void *region;

    ASSERT_NO_FATAL_FAILURE(TestCreateRegion(size, fd, PROT_READ));

    TestProtDenied(fd, size, PROT_WRITE);

    ASSERT_NO_FATAL_FAILURE(TestMmap(fd, size, PROT_READ, &region));

    EXPECT_EQ(0, munmap(region, size));

    ASSERT_NO_FATAL_FAILURE(TestCreateRegion(size, fd, PROT_WRITE));

    TestProtDenied(fd, size, PROT_READ);

    ASSERT_NO_FATAL_FAILURE(TestMmap(fd, size, PROT_WRITE, &region));

    EXPECT_EQ(0, munmap(region, size));

}

TEST(AshmemTest, ForkProtTest) {

    unique_fd fd;

    constexpr size_t size = PAGE_SIZE;

    int protFlags[] = { PROT_READ, PROT_WRITE };

    for (int i = 0; i < 2; i++) {

        ASSERT_NO_FATAL_FAILURE(TestCreateRegion(size, fd, PROT_READ | PROT_WRITE));

        ASSERT_EXIT({

            if (ashmem_set_prot_region(fd, protFlags[i]) >= 0) {

                _exit(0);

            } else {

                _exit(1);

            }

        }, ::testing::ExitedWithCode(0), "");

        ASSERT_NO_FATAL_FAILURE(TestProtDenied(fd, size, protFlags[1-i]));

    }

}

TEST(AshmemTest, ForkMultiRegionTest) {

    constexpr size_t size = PAGE_SIZE;

    uint8_t data[size];

    FillData(data, size);

    constexpr int nRegions = 16;

    unique_fd fd[nRegions];

    for (int i = 0; i < nRegions; i++) {

        ASSERT_NO_FATAL_FAILURE(TestCreateRegion(size, fd[i], PROT_READ | PROT_WRITE));

        void *region;

        ASSERT_NO_FATAL_FAILURE(TestMmap(fd[i], size, PROT_READ | PROT_WRITE, &region));

        memcpy(region, &data, size);

        ASSERT_EQ(0, memcmp(region, &data, size));

        EXPECT_EQ(0, munmap(region, size));

    }

    ASSERT_EXIT({

        for (int i = 0; i < nRegions; i++) {

            void *region = mmap(nullptr, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd[i], 0);

            if (region == MAP_FAILED) {

                _exit(1);

            }

            if (memcmp(region, &data, size) != 0) {

                munmap(region, size);

                _exit(2);

            }

            memset(region, 0, size);

            munmap(region, size);

        }

        _exit(0);

    }, ::testing::ExitedWithCode(0), "");

    memset(&data, 0, size);

    for (int i = 0; i < nRegions; i++) {

        void *region;

        ASSERT_NO_FATAL_FAILURE(TestMmap(fd[i], size, PROT_READ | PROT_WRITE, &region));

        ASSERT_EQ(0, memcmp(region, &data, size));

        EXPECT_EQ(0, munmap(region, size));

    }

}