Adds ability to skip asset files

- fixes #1605
 - prevents rebuild

brut.apktool/apktool-cli/src/main/java/brut/apktool/Main.java

@@ -124,6 +124,9 @@ public class Main {
         if (cli.hasOption("r") || cli.hasOption("no-res")) {
             decoder.setDecodeResources(ApkDecoder.DECODE_RESOURCES_NONE);
         }
+        if (cli.hasOption("no-assets")) {
+            decoder.setDecodeAssets(ApkDecoder.DECODE_ASSETS_NONE);
+        }
         if (cli.hasOption("k") || cli.hasOption("keep-broken-res")) {
             decoder.setKeepBrokenResources(true);
         }
@@ -283,6 +286,11 @@ public class Main {
                 .desc("Do not decode resources.")
                 .build();
 
+        Option noAssetOption = Option.builder()
+                .longOpt("no-assets")
+                .desc("Do not decode assets.")
+                .build();
+
         Option debugDecOption = Option.builder("d")
                 .longOpt("debug")
                 .desc("REMOVED (DOES NOT WORK): Decode in debug mode.")
@@ -396,6 +404,7 @@ public class Main {
             DecodeOptions.addOption(keepResOption);
             DecodeOptions.addOption(analysisOption);
             DecodeOptions.addOption(apiLevelOption);
+            DecodeOptions.addOption(noAssetOption);
 
             BuildOptions.addOption(debugBuiOption);
             BuildOptions.addOption(aaptOption);
@@ -444,6 +453,7 @@ public class Main {
         allOptions.addOption(analysisOption);
         allOptions.addOption(debugDecOption);
         allOptions.addOption(noDbgOption);
+        allOptions.addOption(noAssetOption);
         allOptions.addOption(keepResOption);
         allOptions.addOption(debugBuiOption);
         allOptions.addOption(aaptOption);

brut.apktool/apktool-lib/src/main/java/brut/androlib/Androlib.java

@@ -137,14 +137,17 @@ public class Androlib {
         mAndRes.decodeManifestWithResources(resTable, apkFile, outDir);
     }
 
-    public void decodeRawFiles(ExtFile apkFile, File outDir)
+    public void decodeRawFiles(ExtFile apkFile, File outDir, short decodeAssetMode)
             throws AndrolibException {
         LOGGER.info("Copying assets and libs...");
         try {
             Directory in = apkFile.getDirectory();
+
+            if (decodeAssetMode == ApkDecoder.DECODE_ASSETS_FULL) {
                 if (in.containsDir("assets")) {
                     in.copyToDir(outDir, "assets");
                 }
+            }
             if (in.containsDir("lib")) {
                 in.copyToDir(outDir, "lib");
             }

brut.apktool/apktool-lib/src/main/java/brut/androlib/ApkDecoder.java

@@ -161,7 +161,7 @@ public class ApkDecoder {
                 }
             }
 
-            mAndrolib.decodeRawFiles(mApkFile, outDir);
+            mAndrolib.decodeRawFiles(mApkFile, outDir, mDecodeAssets);
             mAndrolib.decodeUnknownFiles(mApkFile, outDir, mResTable);
             mUncompressedFiles = new ArrayList<String>();
             mAndrolib.recordUncompressedFiles(mApkFile, mUncompressedFiles);
@@ -190,6 +190,13 @@ public class ApkDecoder {
         mDecodeResources = mode;
     }
 
+    public void setDecodeAssets(short mode) throws AndrolibException {
+        if (mode != DECODE_ASSETS_NONE && mode != DECODE_ASSETS_FULL) {
+            throw new AndrolibException("Invalid decode asset mode");
+        }
+        mDecodeAssets = mode;
+    }
+
     public void setAnalysisMode(boolean mode, boolean pass) throws AndrolibException{
         mAnalysisMode = mode;
 
@@ -299,6 +306,9 @@ public class ApkDecoder {
     public final static short DECODE_RESOURCES_NONE = 0x0100;
     public final static short DECODE_RESOURCES_FULL = 0x0101;
 
+    public final static short DECODE_ASSETS_NONE = 0x0000;
+    public final static short DECODE_ASSETS_FULL = 0x0001;
+
     private File getOutDir() throws AndrolibException {
         if (mOutDir == null) {
             throw new AndrolibException("Out dir not set");
@@ -407,6 +417,7 @@ public class ApkDecoder {
     private ResTable mResTable;
     private short mDecodeSources = DECODE_SOURCES_SMALI;
     private short mDecodeResources = DECODE_RESOURCES_FULL;
+    private short mDecodeAssets = DECODE_ASSETS_FULL;
     private boolean mForceDelete = false;
     private boolean mKeepBrokenResources = false;
     private boolean mBakDeb = true;

brut.apktool/apktool-lib/src/test/java/brut/androlib/SkipAssetTest.java

@@ -0,0 +1,90 @@
+/**
+ *  Copyright (C) 2017 Ryszard Wiśniewski <brut.alll@gmail.com>
+ *  Copyright (C) 2017 Connor Tumbleson <connor.tumbleson@gmail.com>
+ *
+ *  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 brut.androlib;
+
+import brut.directory.ExtFile;
+import brut.common.BrutException;
+import brut.util.OS;
+import java.io.File;
+import java.io.IOException;
+
+import org.junit.*;
+import static org.junit.Assert.*;
+
+public class SkipAssetTest {
+
+    @BeforeClass
+    public static void beforeClass() throws Exception {
+        TestUtils.cleanFrameworkFile();
+        sTmpDir = new ExtFile(OS.createTempDirectory());
+        TestUtils.copyResourceDir(SkipAssetTest.class, "brut/apktool/issue1605/", sTmpDir);
+    }
+
+    @AfterClass
+    public static void afterClass() throws BrutException {
+        OS.rmdir(sTmpDir);
+    }
+
+    @Test
+    public void checkIfEnablingSkipAssetWorks() throws BrutException, IOException {
+        String apk = "issue1605.apk";
+
+        // decode issue1605.apk
+        ApkDecoder apkDecoder = new ApkDecoder(new File(sTmpDir + File.separator + apk));
+        sTestOrigDir = new ExtFile(sTmpDir + File.separator + apk + ".out");
+
+        apkDecoder.setOutDir(sTestOrigDir);
+        apkDecoder.setDecodeAssets(ApkDecoder.DECODE_ASSETS_NONE);
+        apkDecoder.setForceDelete(true);
+        apkDecoder.decode();
+
+        checkFileDoesNotExist("assets" + File.separator + "kotlin.kotlin_builtins");
+        checkFileDoesNotExist("assets" + File.separator + "ranges" + File.separator + "ranges.kotlin_builtins");
+    }
+
+    @Test
+    public void checkControl() throws BrutException, IOException {
+        String apk = "issue1605.apk";
+
+        // decode issue1605.apk
+        ApkDecoder apkDecoder = new ApkDecoder(new File(sTmpDir + File.separator + apk));
+        sTestOrigDir = new ExtFile(sTmpDir + File.separator + apk + ".out");
+
+        apkDecoder.setOutDir(sTestOrigDir);
+        apkDecoder.setDecodeAssets(ApkDecoder.DECODE_ASSETS_FULL);
+        apkDecoder.setForceDelete(true);
+        apkDecoder.decode();
+
+        checkFileDoesExist("assets" + File.separator + "kotlin.kotlin_builtins");
+        checkFileDoesExist("assets" + File.separator + "ranges" + File.separator + "ranges.kotlin_builtins");
+    }
+
+    private void checkFileDoesNotExist(String path) throws BrutException {
+        File f =  new File(sTestOrigDir, path);
+
+        assertFalse(f.isFile());
+    }
+
+    private void checkFileDoesExist(String path) throws BrutException {
+        File f =  new File(sTestOrigDir, path);
+
+        assertTrue(f.isFile());
+    }
+
+    private static ExtFile sTmpDir;
+    private static ExtFile sTestOrigDir;
+}