Android 热修复方案Tinker(二) 补丁加载流程

基于Tinker V1.7.5

• Android 热修复方案Tinker(一) Application改造
• Android 热修复方案Tinker(二) 补丁加载流程
• Android 热修复方案Tinker(三) Dex补丁加载
• Android 热修复方案Tinker(四) 资源补丁加载
• Android 热修复方案Tinker(五) SO补丁加载
• Android 热修复方案Tinker(六) Gradle插件实现
• Android 热修复方案Tinker(七) 插桩实现
• 带注释的源码

这篇文章从加载补丁的入口tryLoad处开始分析Tinker补丁加载的流程.根据不同的类别Tinker可以支持dex,SO和资源更新,接下来会详细分析.先贴出补丁加载的主要类图.

从tryLoad入口开始,tryLoad中调用加载补丁流程的方法,并统计出这次Load Patch所消耗的时间.

Intent resultIntent = new Intent();

//统计 load patch 耗时
long begin = SystemClock.elapsedRealtime();
tryLoadPatchFilesInternal(app, tinkerFlag, tinkerLoadVerifyFlag, resultIntent);
long cost = SystemClock.elapsedRealtime() - begin;
IntentUtil.setIntentPatchCostTime(resultIntent, cost);
return resultIntent;

在tryLoadPatchFilesInternal中会先做一系列的环境校验,一切就绪之后才真正将加工过的补丁加载到运行环境中.下面按顺序罗列出环境校验的过程.

1. 检查tinkerFlag是否设置了enable ? continue : 记录ERROR_LOAD_DISABLE到result中,return.

   if (!ShareTinkerInternals.isTinkerEnabled(tinkerFlag)) {
       ShareIntentUtil.setIntentReturnCode(resultIntent, ShareConstants.ERROR_LOAD_DISABLE);
       return;
   }
   

2. 检查补丁工作空间/tinker是否已经存在 ? continue : 记录ERROR_LOAD_PATCH_DIRECTORY_NOT_EXIST到result中,return.

   File patchDirectoryFile = SharePatchFileUtil.getPatchDirectory(app);
   if (patchDirectoryFile == null) {
       Log.w(TAG, "tryLoadPatchFiles:getPatchDirectory == null");
       //treat as not exist
       ShareIntentUtil.setIntentReturnCode(resultIntent, ShareConstants.ERROR_LOAD_PATCH_DIRECTORY_NOT_EXIST);
       return;
   }
   String patchDirectoryPath = patchDirectoryFile.getAbsolutePath();
   
   //检查补丁路径是否存在
   if (!patchDirectoryFile.exists()) {
       Log.w(TAG, "tryLoadPatchFiles:patch dir not exist:" + patchDirectoryPath);
       ShareIntentUtil.setIntentReturnCode(resultIntent, ShareConstants.ERROR_LOAD_PATCH_DIRECTORY_NOT_EXIST);
       return;
   }
   

3. 检查/tinker/patch.info 补丁信息文件是否存在 ? continue : 记录ERROR_LOAD_PATCH_INFO_NOT_EXIST到result中,return.

   //tinker/patch.info
   File patchInfoFile = SharePatchFileUtil.getPatchInfoFile(patchDirectoryPath);
   
   //check patch info file whether exist
   if (!patchInfoFile.exists()) {
       Log.w(TAG, "tryLoadPatchFiles:patch info not exist:" + patchInfoFile.getAbsolutePath());
       ShareIntentUtil.setIntentReturnCode(resultIntent, ShareConstants.ERROR_LOAD_PATCH_INFO_NOT_EXIST);
       return;
   }
   

4. patch.info文件中存储了如下新旧两个版本补丁的MD5.先用lock文件加锁,然后检查patch info能否读出有效的补丁信息 ? continue : 记录ERROR_LOAD_PATCH_INFO_CORRUPTED到result中,return.

   //old = 641e634c5b8f1649c75caf73794acbdf
   //new = 2c150d8560334966952678930ba67fa8
   File patchInfoLockFile = SharePatchFileUtil.getPatchInfoLockFile(patchDirectoryPath);
   
   //通过lockFile加锁, 检查patch info文件中的补丁版本信息
   patchInfo = SharePatchInfo.readAndCheckPropertyWithLock(patchInfoFile, patchInfoLockFile);
   if (patchInfo == null) {
       ShareIntentUtil.setIntentReturnCode(resultIntent, ShareConstants.ERROR_LOAD_PATCH_INFO_CORRUPTED);
       return;
   }
   

5. 检查补丁信息中的数据是否有效? 将信息记录到result中,continue : 记录ERROR_LOAD_PATCH_INFO_CORRUPTED到result中,return.

   String oldVersion = patchInfo.oldVersion;
   String newVersion = patchInfo.newVersion;
   
   if (oldVersion == null || newVersion == null) {
       //it is nice to clean patch
       Log.w(TAG, "tryLoadPatchFiles:onPatchInfoCorrupted");
       ShareIntentUtil.setIntentReturnCode(resultIntent, ShareConstants.ERROR_LOAD_PATCH_INFO_CORRUPTED);
       return;
   }
   
   resultIntent.putExtra(ShareIntentUtil.INTENT_PATCH_OLD_VERSION, oldVersion);
   resultIntent.putExtra(ShareIntentUtil.INTENT_PATCH_NEW_VERSION, newVersion);
   

6. 根据版本变化和是否是主进程的条件决定是否允许加载最新的补丁,并检查该补丁的MD5标识是否不为空 ? continue : 记录ERROR_LOAD_PATCH_INFO_BLANK到result中,return.

   boolean mainProcess = ShareTinkerInternals.isInMainProcess(app);
   boolean versionChanged = !(oldVersion.equals(newVersion));
   
   //如果版本变化,并且当前运行在主进程,则允许加载最新补丁
   String version = oldVersion;
   if (versionChanged && mainProcess) {
       version = newVersion;
   }
   
   //检查当前补丁版本的MD5标识是否为空
   if (ShareTinkerInternals.isNullOrNil(version)) {
       Log.w(TAG, "tryLoadPatchFiles:version is blank, wait main process to restart");
       ShareIntentUtil.setIntentReturnCode(resultIntent, ShareConstants.ERROR_LOAD_PATCH_INFO_BLANK);
       return;
   }
   

7. 检查当前版本补丁路径是否存在 ? continue : 记录ERROR_LOAD_PATCH_VERSION_DIRECTORY_NOT_EXIST到result中,return.

   //patch-641e634c
   String patchName = SharePatchFileUtil.getPatchVersionDirectory(version);
   
   //tinker/patch.info/patch-641e634c
   String patchVersionDirectory = patchDirectoryPath + "/" + patchName;
   File patchVersionDirectoryFile = new File(patchVersionDirectory);
   
   //检查当前版本补丁路径是否存在
   if (!patchVersionDirectoryFile.exists()) {
       Log.w(TAG, "tryLoadPatchFiles:onPatchVersionDirectoryNotFound");
       //we may delete patch info file
       ShareIntentUtil.setIntentReturnCode(resultIntent, ShareConstants.ERROR_LOAD_PATCH_VERSION_DIRECTORY_NOT_EXIST);
       return;
   }
   

8. 检查补丁文件是否存在 ? continue : 记录ERROR_LOAD_PATCH_VERSION_FILE_NOT_EXIST到result中,return.

   //tinker/patch.info/patch-641e634c/patch-641e634c.apk
   File patchVersionFile = new File(patchVersionDirectoryFile.getAbsolutePath(), SharePatchFileUtil.getPatchVersionFile(version));
   
   //检查补丁文件是否存在
   if (!patchVersionFile.exists()) {
       Log.w(TAG, "tryLoadPatchFiles:onPatchVersionFileNotFound");
       //we may delete patch info file
       ShareIntentUtil.setIntentReturnCode(resultIntent, ShareConstants.ERROR_LOAD_PATCH_VERSION_FILE_NOT_EXIST);
       return;
   }
   

9. 检查补丁文件签名和Tinker id是否一致 ？ 将补丁的相关信息存入resultIntent,continue : 记录ERROR_LOAD_PATCH_PACKAGE_CHECK_FAIL和检查结果到result中,return.

   ShareSecurityCheck securityCheck = new ShareSecurityCheck(app);
   
   //检查补丁文件签名和Tinker id是否一致
   int returnCode = ShareTinkerInternals.checkTinkerPackage(app, tinkerFlag, patchVersionFile, securityCheck);
   if (returnCode != ShareConstants.ERROR_PACKAGE_CHECK_OK) {
       Log.w(TAG, "tryLoadPatchFiles:checkTinkerPackage");
       resultIntent.putExtra(ShareIntentUtil.INTENT_PATCH_PACKAGE_PATCH_CHECK, returnCode);
       ShareIntentUtil.setIntentReturnCode(resultIntent, ShareConstants.ERROR_LOAD_PATCH_PACKAGE_CHECK_FAIL);
       return;
   }
   
   resultIntent.putExtra(ShareIntentUtil.INTENT_PATCH_PACKAGE_CONFIG, securityCheck.getPackagePropertiesIfPresent());
   

   这里为了快速校验,就只检验补丁包内部以meta.txt结尾的文件的签名. 其他的文件的合法性则通过校验过的meta.txt文件内部的补丁文件Md5校验.这里只是把meta.txt的内容分别存入到metaContentMap中,以供外部使用.

   while (entries.hasMoreElements()) {
       JarEntry jarEntry = entries.nextElement();
       // no code
       if (jarEntry == null) {
           continue;
       }
   
       final String name = jarEntry.getName();
       if (name.startsWith("META-INF/")) {
           continue;
       }
       //for faster, only check the meta.txt files
       //we will check other files's mad5 written in meta files
       if (!name.endsWith(ShareConstants.META_SUFFIX)) {
           continue;
       }
       metaContentMap.put(name, SharePatchFileUtil.loadDigestes(jarFile, jarEntry));
       Certificate[] certs = jarEntry.getCertificates();
       if (certs == null) {
           return false;
       }
       if (!check(path, certs)) {
           return false;
       }
   }
   

   根据不同的情况,最多有四个文件是以meta.txt结尾的:

   • package_meta.txt 补丁包的基本信息
   • dex_meta.txt 所有dex文件的信息
   • so_meta.txt 所有so文件的信息
   • res_meta.txt 所有资源文件的信息

10. 如果支持dex修复 则继续检查dex补丁文件是否存在 ? continue : log, return.

    final boolean isEnabledForDex = ShareTinkerInternals.isTinkerEnabledForDex(tinkerFlag);
    
    if (isEnabledForDex) {
        //tinker/patch.info/patch-641e634c/dex
        boolean dexCheck = TinkerDexLoader.checkComplete(patchVersionDirectory, securityCheck, resultIntent);
        if (!dexCheck) {
            //file not found, do not load patch
            Log.w(TAG, "tryLoadPatchFiles:dex check fail");
            return;
        }
    }
    

    至于checkComplete都校验了哪些东西？可以继续往里面看.先根据第9步中读取到内存中的dex_meta.txt数据,在parseDexDiffPatchInfo内部将字符串以dex为单位切割出每个dex文件的详细信息.

    String meta = securityCheck.getMetaContentMap().get(DEX_MEAT_FILE);
    //not found dex
    if (meta == null) {
        return true;
    }
    dexList.clear();
    ShareDexDiffPatchInfo.parseDexDiffPatchInfo(meta, dexList);
    
    if (dexList.isEmpty()) {
        return true;
    }
    

    将dex摘要信息有效的item过滤出来,再遍历过滤出来的dex,去/tinker/patch.info/patch-xxx/dex和/tinker/patch.info/patch-xxx/odex下验证物理文件是否存在.

    HashMap dexes = new HashMap<>();
    
    for (ShareDexDiffPatchInfo info : dexList) {
        //for dalvik, ignore art support dex
        if (isJustArtSupportDex(info)) {
            continue;
        }
        if (!ShareDexDiffPatchInfo.checkDexDiffPatchInfo(info)) {
            intentResult.putExtra(ShareIntentUtil.INTENT_PATCH_PACKAGE_PATCH_CHECK, ShareConstants.ERROR_PACKAGE_CHECK_DEX_META_CORRUPTED);
            ShareIntentUtil.setIntentReturnCode(intentResult, ShareConstants.ERROR_LOAD_PATCH_PACKAGE_CHECK_FAIL);
            return false;
        }
        dexes.put(info.realName, info.destMd5InDvm);
    }
    

11. 如果支持so修复 则继续检查so补丁文件是否存在,校验的方式同第10步.

    final boolean isEnabledForNativeLib = ShareTinkerInternals.isTinkerEnabledForNativeLib(tinkerFlag);
    
    if (isEnabledForNativeLib) {
        //tinker/patch.info/patch-641e634c/lib
        boolean libCheck = TinkerSoLoader.checkComplete(patchVersionDirectory, securityCheck, resultIntent);
        if (!libCheck) {
            //file not found, do not load patch
            Log.w(TAG, "tryLoadPatchFiles:native lib check fail");
            return;
        }
    }
    

12. 如果支持资源修复 则继续检查资源补丁文件是否存在,校验的方式同第10步.

    final boolean isEnabledForResource = ShareTinkerInternals.isTinkerEnabledForResource(tinkerFlag);
    Log.w(TAG, "tryLoadPatchFiles:isEnabledForResource:" + isEnabledForResource);
    if (isEnabledForResource) {
        boolean resourceCheck = TinkerResourceLoader.checkComplete(app, patchVersionDirectory, securityCheck, resultIntent);
        if (!resourceCheck) {
            //file not found, do not load patch
            Log.w(TAG, "tryLoadPatchFiles:resource check fail");
            return;
        }
    }
    

13. 符合条件的话就更新版本信息,并将最新的patch info更新入文件.在v1.7.5的版本开始有了isSystemOTA判断,只要用户是ART环境并且做了OTA升级则在加载dex补丁的时候就会先把最近一次的补丁全部DexFile.loadDex一遍重新生成odex.再加载dex补丁.

    //only work for art platform oat
    boolean isSystemOTA = ShareTinkerInternals.isVmArt() && ShareTinkerInternals.isSystemOTA(patchInfo.fingerPrint);
    
    //we should first try rewrite patch info file, if there is a error, we can't load jar
    if (isSystemOTA || (mainProcess && versionChanged)) {
        patchInfo.oldVersion = version;
        //update old version to new
        if (!SharePatchInfo.rewritePatchInfoFileWithLock(patchInfoFile, patchInfo, patchInfoLockFile)) {
            ShareIntentUtil.setIntentReturnCode(resultIntent, ShareConstants.ERROR_LOAD_PATCH_REWRITE_PATCH_INFO_FAIL);
            Log.w(TAG, "tryLoadPatchFiles:onReWritePatchInfoCorrupted");
            return;
        }
    }
    

14. 检查safe mode计数是否超过三次

    if (!checkSafeModeCount(app)) {
        resultIntent.putExtra(ShareIntentUtil.INTENT_PATCH_EXCEPTION, new TinkerRuntimeException("checkSafeModeCount fail"));
        ShareIntentUtil.setIntentReturnCode(resultIntent, ShareConstants.ERROR_LOAD_PATCH_UNCAUGHT_EXCEPTION);
        Log.w(TAG, "tryLoadPatchFiles:checkSafeModeCount fail");
        return;
    }
    

15. 在符合条件的情况下加载dex,res补丁.并记录成功状态.

    //now we can load patch jar
    if (isEnabledForDex) {
        boolean loadTinkerJars = TinkerDexLoader.loadTinkerJars(app, tinkerLoadVerifyFlag, patchVersionDirectory, resultIntent);
        if (!loadTinkerJars) {
            Log.w(TAG, "tryLoadPatchFiles:onPatchLoadDexesFail");
            return;
        }
    }
    
    //now we can load patch resource
    if (isEnabledForResource) {
        boolean loadTinkerResources = TinkerResourceLoader.loadTinkerResources(app, tinkerLoadVerifyFlag, patchVersionDirectory, resultIntent);
        if (!loadTinkerResources) {
            Log.w(TAG, "tryLoadPatchFiles:onPatchLoadResourcesFail");
            return;
        }
    }
    //all is ok!
    ShareIntentUtil.setIntentReturnCode(resultIntent, ShareConstants.ERROR_LOAD_OK);
    

接下来详细分析dex,so和资源补丁更新的原理.

---

转载请注明出处:http://blog.csdn.net/l2show/article/details/53240023