继上一篇系统 Lanucher App开发，遇到的最坑的点记录，如果不知道怎么将apk变成系统apk，请看《系统Lanucher app开发》
当我开心的以为我的程序成了系统app再也无忧的时候，果然又出现了一个bug，.so的库找不到了，于是我去/data/data/底下的app安装目录里寻找，果然唯独少了so文件，这是什么情况?
苦思冥想开始分析原因:
当我们app push到system/app目录下成为系统级app时，app默认加载so库的路径变成了system/lib，而system/lib却是只读的，导致so库无法正常解压
知道了原因，于是就开始解决方案:
1.将所有的so库提取出来放到system/lib目录下
于是开始实验
同样用上面的mount命令获取system的读写权限，再将so库依次push进system/lib 重启手机，发现程序运行成功了，可是发现了这样做的缺点，不便于调试，因为我们项目有很多自己的.so库，所以就需要嵌入式只要给我们so
库，我们就得替换一个新的进去，如果这样放在system/lib的目录，每次都得push最新的进去，确实麻烦，我们的嵌入式大神也规劝我不要这么干，这样会污染系统本身自带的so库，后续可能会有一些不必要的麻烦
于是又开始寻找新方案解决
2.在程序最开始运行如下Java代码
思路就是复制apk中的.so库到/data/data/app的安装目录中，再通过反射更改app加载so库的路径，将nativeLibraryDir这个属性获取并修改成我们解压so库的目标路径，所有加载so库的方法都放在这个类执行之后开始，这个时候重新打包运行，发现在/data/data/apk的安装目录里，之前没有的
so库出现了，程序也正常运行
最后总结一下优缺点:优点是便于调试，不用更改一个so库就得push一下，可以动态加载
缺点是 路子有点野，属于奇淫巧技之类，可能会留下坑
public class StatSoFiles {
private static final String TAG = StatSoFiles.class.getSimpleName();
private static final String APK_REINSTALL = "apk_reinstall";
private Context mContext;
private List<String> mApkSoFiles = new ArrayList<>();
private String APK_PATH;
private final boolean mIs64Bit = false;
private final String mApkLibPath;
public StatSoFiles(Context context) {
mContext = context;
APK_PATH = mContext.getApplicationInfo().sourceDir;
// mIs64Bit = MiscUtils.is64Bit();
//初始化要释放so文件的路径
mApkLibPath = "lib/armeabi-v7a";
}
//释放so文件
public boolean verifyAndReleaseLibSo() {
initSoFileName();
for (int i = 0; i < mApkSoFiles.size(); i++) {
String soFile = mApkSoFiles.get(i);
boolean inAppLib = isInAppLib(soFile);
// if (inAppLib) {
// } else {
//将so文件写到应用的包路径下
writeSoToDir(soFile);
// }
}
boolean testLoadLibrary = testLoadLibrary();
return testLoadLibrary;
}
public boolean testLoadLibrary() {
//检测so文件释放能成功加载
try {
System.loadLibrary("cvc");
return true;
} catch (Throwable e) {
return false;
}
}
private void initSoFileName() {
//从apk中获得所有so文件名
InputStream in = null;
ZipInputStream zin = null;
try {
in = new BufferedInputStream(new FileInputStream(APK_PATH));
zin = new ZipInputStream(in);
ZipEntry ze;
while ((ze = zin.getNextEntry()) != null) {
String soName = ze.getName();
if (soName != null && soName.startsWith(mApkLibPath)) {
mApkSoFiles.add(soName.replace(mApkLibPath, ""));
}
}
} catch (Exception e) {
} finally {
if (zin != null) {
try {
zin.close();
} catch (Exception e) {
}
}
if (in != null) {
try {
in.close();
} catch (Exception e) {
}
}
}
}
private void writeSoToDir(String soName) {
if (TextUtils.isEmpty(APK_PATH)) {
return;
}
ZipFile zf = null;
BufferedOutputStream bof = null;
BufferedInputStream fb = null;
try {
zf = new ZipFile(APK_PATH);
ZipEntry ze = zf.getEntry(mApkLibPath + soName);
fb = new BufferedInputStream(zf.getInputStream(ze));
File libs = mContext.getDir("libs", Context.MODE_PRIVATE);
if (!libs.exists()) {
libs.mkdirs();
}
File file = new File(libs, soName);
bof = new BufferedOutputStream(new FileOutputStream(file));
byte[] buff = new byte[4096];
int len = 0;
while ((len = fb.read(buff)) != -1) {
bof.write(buff, 0, len);
}
} catch (IOException e) {
} finally {
closeStream(zf, bof, fb);
}
}
private void closeStream(ZipFile zf, BufferedOutputStream bof, BufferedInputStream fb) {
try {
if (bof != null) {
bof.close();
}
} catch (IOException e) {
}
try {
if (fb != null) {
fb.close();
}
} catch (IOException e) {
}
try {
if (zf != null) {
zf.close();
}
} catch (IOException e) {
}
}
private boolean isInAppLib(String soName) {
File dir = mContext.getDir("libs", Context.MODE_PRIVATE);
String appLibPath = dir.getAbsolutePath() + "/" + soName;
File appLibSoFile = new File(appLibPath);
if (appLibSoFile.exists()) {
long soSize = appLibSoFile.length();
ZipFile zf = null;
try {
zf = new ZipFile(APK_PATH);
ZipEntry ze = zf.getEntry(mApkLibPath + soName);
long size = ze.getSize();
if (size == soSize) {
return true;
} else {
appLibSoFile.delete();
return false;
}
} catch (IOException e) {
} finally {
if (zf != null) {
try {
zf.close();
} catch (IOException e) {
}
}
}
}
return false;
}
//修改加载so的路径
public void initNativeDirectory(Context context) {
if (hasDexClassLoader()) { // 4.0以上系统
try {
// SLog.d(TAG, "AboveEqualApiLevel14");
createNewNativeDirAboveEqualApiLevel14(context);
} catch (Exception e) {
try {
//6.0系统
createNewNativeDirAboveEqualApiLevel21(context);
} catch (Exception e1) {
e1.printStackTrace();
}
}
} else {
try {
createNewNativeDirBelowApiLevel14(context); // 4.0以下系统
} catch (Exception e) {
}
}
}
private void createNewNativeDirAboveEqualApiLevel21(Context context)
throws IllegalAccessException, NoSuchFieldException, ClassNotFoundException {
if (Build.VERSION.SDK_INT > Build.VERSION_CODES.LOLLIPOP) {
PathClassLoader pathClassLoader = (PathClassLoader) context.getClassLoader();
Object pathList = getPathList(pathClassLoader);
Class<?> elementClass = Class.forName("dalvik.system.DexPathList$Element");
Constructor<?> element = null;
try {
element = elementClass.getConstructor(File.class, boolean.class, File.class, DexFile.class);
} catch (NoSuchMethodException e) {
}
Object systemNativeLibraryDirectories = pathList.getClass()
.getDeclaredField("systemNativeLibraryDirectories");
Object nativeLibraryDirectories = pathList.getClass().getDeclaredField("nativeLibraryDirectories");
Object nativeLibraryPathElements = pathList.getClass().getDeclaredField("nativeLibraryPathElements");
((Field) systemNativeLibraryDirectories).setAccessible(true);
((Field) nativeLibraryDirectories).setAccessible(true);
((Field) nativeLibraryPathElements).setAccessible(true);
// 获取 DEXPATHList中的属性值
List<File> systemFiles = (List<File>) ((Field) systemNativeLibraryDirectories).get(pathList);
List<File> nativeFiles = (List<File>) ((Field) nativeLibraryDirectories).get(pathList);
Object[] elementFiles = (Object[]) ((Field) nativeLibraryPathElements).get(pathList);
Object newElementFiles = Array.newInstance(elementClass, elementFiles.length + 1);
systemFiles.add(context.getDir("libs", Context.MODE_PRIVATE));
nativeFiles.add(context.getDir("libs", Context.MODE_PRIVATE));
((Field) systemNativeLibraryDirectories).set(pathList, systemFiles);
((Field) nativeLibraryDirectories).set(pathList, nativeFiles);
if (element != null) {
try {
Object newInstance = element.newInstance(
new File(context.getDir("libs", Context.MODE_PRIVATE).getAbsolutePath()), true, null, null);
Array.set(newElementFiles, 0, newInstance);
for (int i = 1; i < elementFiles.length + 1; i++) {
Array.set(newElementFiles, i, elementFiles[i - 1]);
}
((Field) nativeLibraryPathElements).set(pathList, newElementFiles);
} catch (InstantiationException | InvocationTargetException e) {
}
}
}
}
private void createNewNativeDirBelowApiLevel14(Context context)
throws NoSuchFieldException, IllegalAccessException {
PathClassLoader pathClassLoader = (PathClassLoader) context.getClassLoader();
Field mLibPaths = pathClassLoader.getClass().getDeclaredField("mLibPaths");
mLibPaths.setAccessible(true);
String[] libs = (String[]) (mLibPaths).get(pathClassLoader);
Object newPaths = Array.newInstance(String.class, libs.length + 1);
// 添加自定义.so路径
Array.set(newPaths, 0, context.getDir("libs", Context.MODE_PRIVATE).getAbsolutePath());
// 将系统自己的追加上
for (int i = 1; i < libs.length + 1; i++) {
Array.set(newPaths, i, libs[i - 1]);
}
mLibPaths.set(pathClassLoader, newPaths);
}
private void createNewNativeDirAboveEqualApiLevel14(Context context) throws Exception {
PathClassLoader pathClassLoader = (PathClassLoader) context.getClassLoader();
Object pathList = getPathList(pathClassLoader);
// 获取当前类的属性
Object nativeLibraryDirectories = pathList.getClass().getDeclaredField("nativeLibraryDirectories");
((Field) nativeLibraryDirectories).setAccessible(true);
// 获取 DEXPATHList中的属性值
File[] files = (File[]) ((Field) nativeLibraryDirectories).get(pathList);
Object newfiles = Array.newInstance(File.class, files.length + 1);
// 添加自定义.so路径
Array.set(newfiles, 0, context.getDir("libs", Context.MODE_PRIVATE));
// 将系统自己的追加上
for (int i = 1; i < files.length + 1; i++) {
Array.set(newfiles, i, files[i - 1]);
}
((Field) nativeLibraryDirectories).set(pathList, newfiles);
}
private Object getPathList(Object obj) throws ClassNotFoundException, NoSuchFieldException, IllegalAccessException {
return getField(obj, Class.forName("dalvik.system.BaseDexClassLoader"), "pathList");
}
private Object getField(Object obj, Class cls, String str) throws NoSuchFieldException, IllegalAccessException {
Field declaredField = cls.getDeclaredField(str);
declaredField.setAccessible(true);
return declaredField.get(obj);
}
private boolean hasDexClassLoader() {
try {
Class.forName("dalvik.system.BaseDexClassLoader");
return true;
} catch (ClassNotFoundException var1) {
return false;
}
}
}
