Deconstructed APK prototyping

apk/hijack/org/chromium/deconstructed/NativeInstaller.java

+package org.chromium.deconstructed;
+
+import android.content.Context;
+import android.content.pm.ApplicationInfo;
+import android.util.Log;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.lang.reflect.InvocationTargetException;
+
+public class NativeInstaller {
+    private static final String TAG = "org.chromium.deconstructed.NativeInstaller";
+    private static final String NATIVE_LIB_DIR_NAME =
+            "code_cache" + File.separator + "lib";
+
+    public static void install(Context context, File nativeDir)
+            throws IOException, NoSuchFieldException {
+        File[] nativeLibs = nativeDir.listFiles();
+        for (File f : nativeLibs) {
+            if (!isValidLib(f)) {
+                return;
+            }
+        }
+        ApplicationInfo appInfo = context.getApplicationInfo();
+        File installDir = new File(appInfo.dataDir, NATIVE_LIB_DIR_NAME);
+        installDir.mkdirs();
+        android.util.Log.e(TAG, installDir.toString());
+        for (File f : nativeLibs) {
+            File e = new File(installDir, f.getName());
+            copyFile(f, e);
+            e.setExecutable(true);
+        }
+
+        injectNativeLibDir(context.getClassLoader(), installDir);
+    }
+
+    private static boolean isValidLib(File f) {
+        // TODO
+        return true;
+    }
+
+    private static void copyFile(File in, File out) throws IOException {
+        InputStream src = null;
+        OutputStream dst = null;
+        try {
+            src = new FileInputStream(in);
+            dst = new FileOutputStream(out);
+            byte[] buf = new byte[1 << 14]; // 16k
+            int len;
+            while ((len = src.read(buf)) > 0) {
+                dst.write(buf, 0, len);
+            }
+        } finally {
+            // TODO: blegh
+            if (src != null) {
+                src.close();
+            }
+            if (dst != null) {
+                dst.close();
+            }
+        }
+
+    }
+
+    private static void injectNativeLibDir(ClassLoader loader, File nativeLibDir) throws NoSuchFieldException {
+        Object dexPathList = Reflect.getField(loader, "pathList");
+        Object[] currentDirs = (Object[]) Reflect.getField(dexPathList, "nativeLibraryDirectories");
+        Object[] newDirs = new Object[] {nativeLibDir};
+        Reflect.setField(dexPathList, "nativeLibraryDirectories", Reflect.concatArrays(currentDirs, newDirs));
+    }
+}