src/test/java/com/android/apkzlib/zfile/ApkAlignmentTest.java

/*
 * Copyright (C) 2017 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.
 */

package com.android.apkzlib.zfile;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertTrue;

import com.android.apkzlib.zip.CompressionMethod;
import com.android.apkzlib.zip.StoredEntry;
import com.android.apkzlib.zip.ZFile;
import com.android.apkzlib.zip.ZFileOptions;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.nio.file.Files;
import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.TemporaryFolder;

public class ApkAlignmentTest {
    @Rule public TemporaryFolder mTemporaryFolder = new TemporaryFolder();

    @Test
    public void soFilesUncompressedAndAligned() throws Exception {
        File apk = new File(mTemporaryFolder.getRoot(), "a.apk");

        File soFile = new File(mTemporaryFolder.getRoot(), "doesnt_work.so");
        Files.write(soFile.toPath(), new byte[500]);

        ApkZFileCreatorFactory cf = new ApkZFileCreatorFactory(new ZFileOptions());
        ApkCreatorFactory.CreationData creationData =
                new ApkCreatorFactory.CreationData(
                        apk,
                        null,
                        null,
                        false,
                        false,
                        null,
                        null,
                        20,
                        NativeLibrariesPackagingMode.UNCOMPRESSED_AND_ALIGNED,
                        path -> false);

        ApkCreator creator = cf.make(creationData);

        creator.writeFile(soFile, "/doesnt_work.so");
        creator.close();

        try (ZFile zf = new ZFile(apk)) {
            StoredEntry soEntry = zf.get("/doesnt_work.so");
            assertNotNull(soEntry);
            assertEquals(
                    CompressionMethod.STORE,
                    soEntry.getCentralDirectoryHeader().getCompressionInfoWithWait().getMethod());
            long offset =
                    soEntry.getCentralDirectoryHeader().getOffset() + soEntry.getLocalHeaderSize();
            assertTrue(offset % 4096 == 0);
        }
    }

    @Test
    public void soFilesMergedFromZipsCanBeUncompressedAndAligned() throws Exception {

        // Create a zip file with a compressed, unaligned so file.
        File zipToMerge = new File(mTemporaryFolder.getRoot(), "a.zip");
        try (ZFile zf = new ZFile(zipToMerge)) {
            zf.add("/zero.so", new ByteArrayInputStream(new byte[500]));
        }

        try (ZFile zf = new ZFile(zipToMerge)) {
            StoredEntry zeroSo = zf.get("/zero.so");
            assertNotNull(zeroSo);
            assertEquals(
                    CompressionMethod.DEFLATE,
                    zeroSo.getCentralDirectoryHeader().getCompressionInfoWithWait().getMethod());
            long offset =
                    zeroSo.getCentralDirectoryHeader().getOffset() + zeroSo.getLocalHeaderSize();
            assertFalse(offset % 4096 == 0);
        }

        // Create an APK and merge the zip file.
        File apk = new File(mTemporaryFolder.getRoot(), "b.apk");
        ApkZFileCreatorFactory cf = new ApkZFileCreatorFactory(new ZFileOptions());
        ApkCreatorFactory.CreationData creationData =
                new ApkCreatorFactory.CreationData(
                        apk,
                        null,
                        null,
                        false,
                        false,
                        null,
                        null,
                        20,
                        NativeLibrariesPackagingMode.UNCOMPRESSED_AND_ALIGNED,
                        path -> false);

        try (ApkCreator creator = cf.make(creationData)) {
            creator.writeZip(zipToMerge, null, null);
        }

        // Make sure the file is uncompressed and aligned.
        try (ZFile zf = new ZFile(apk)) {
            StoredEntry soEntry = zf.get("/zero.so");
            assertNotNull(soEntry);
            assertEquals(
                    CompressionMethod.STORE,
                    soEntry.getCentralDirectoryHeader().getCompressionInfoWithWait().getMethod());
            long offset =
                    soEntry.getCentralDirectoryHeader().getOffset() + soEntry.getLocalHeaderSize();
            assertTrue(offset % 4096 == 0);

            byte[] data = soEntry.read();
            assertEquals(500, data.length);
            for (int i = 0; i < data.length; i++) {
                assertEquals(0, data[i]);
            }
        }
    }

    @Test
    public void soFilesUncompressedAndNotAligned() throws Exception {
        File apk = new File(mTemporaryFolder.getRoot(), "a.apk");

        File soFile = new File(mTemporaryFolder.getRoot(), "doesnt_work.so");
        Files.write(soFile.toPath(), new byte[500]);

        ApkZFileCreatorFactory cf = new ApkZFileCreatorFactory(new ZFileOptions());
        ApkCreatorFactory.CreationData creationData =
                new ApkCreatorFactory.CreationData(
                        apk,
                        null,
                        null,
                        false,
                        false,
                        null,
                        null,
                        20,
                        NativeLibrariesPackagingMode.COMPRESSED,
                        path -> false);

        ApkCreator creator = cf.make(creationData);

        creator.writeFile(soFile, "/doesnt_work.so");
        creator.close();

        try (ZFile zf = new ZFile(apk)) {
            StoredEntry soEntry = zf.get("/doesnt_work.so");
            assertNotNull(soEntry);
            assertEquals(
                    CompressionMethod.DEFLATE,
                    soEntry.getCentralDirectoryHeader().getCompressionInfoWithWait().getMethod());
            long offset =
                    soEntry.getCentralDirectoryHeader().getOffset() + soEntry.getLocalHeaderSize();
            assertTrue(offset % 4096 != 0);
        }
    }

    @Test
    public void soFilesMergedFromZipsCanBeUncompressedAndNotAligned() throws Exception {

        // Create a zip file with a compressed, unaligned so file.
        File zipToMerge = new File(mTemporaryFolder.getRoot(), "a.zip");
        try (ZFile zf = new ZFile(zipToMerge)) {
            zf.add("/zero.so", new ByteArrayInputStream(new byte[500]));
        }

        try (ZFile zf = new ZFile(zipToMerge)) {
            StoredEntry zeroSo = zf.get("/zero.so");
            assertNotNull(zeroSo);
            assertEquals(
                    CompressionMethod.DEFLATE,
                    zeroSo.getCentralDirectoryHeader().getCompressionInfoWithWait().getMethod());
            long offset =
                    zeroSo.getCentralDirectoryHeader().getOffset() + zeroSo.getLocalHeaderSize();
            assertFalse(offset % 4096 == 0);
        }

        // Create an APK and merge the zip file.
        File apk = new File(mTemporaryFolder.getRoot(), "b.apk");
        ApkZFileCreatorFactory cf = new ApkZFileCreatorFactory(new ZFileOptions());
        ApkCreatorFactory.CreationData creationData =
                new ApkCreatorFactory.CreationData(
                        apk,
                        null,
                        null,
                        false,
                        false,
                        null,
                        null,
                        20,
                        NativeLibrariesPackagingMode.COMPRESSED,
                        path -> false);

        try (ApkCreator creator = cf.make(creationData)) {
            creator.writeZip(zipToMerge, null, null);
        }

        // Make sure the file is uncompressed and aligned.
        try (ZFile zf = new ZFile(apk)) {
            StoredEntry soEntry = zf.get("/zero.so");
            assertNotNull(soEntry);
            assertEquals(
                    CompressionMethod.DEFLATE,
                    soEntry.getCentralDirectoryHeader().getCompressionInfoWithWait().getMethod());
            long offset =
                    soEntry.getCentralDirectoryHeader().getOffset() + soEntry.getLocalHeaderSize();
            assertTrue(offset % 4096 != 0);

            byte[] data = soEntry.read();
            assertEquals(500, data.length);
            for (int i = 0; i < data.length; i++) {
                assertEquals(0, data[i]);
            }
        }
    }
}