com.nasatrainedmonkeys.roboinstaller.RoboInstaller.java Source code

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Here is the source code for com.nasatrainedmonkeys.roboinstaller.RoboInstaller.java

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/*
50AH-code
=========
    
50 Android Hacks (http://manning.com/sessa/) book source code
    
    
Copyright (c) 2012 Manning
    
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
    
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
    
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
    
    
*/

package com.nasatrainedmonkeys.roboinstaller;

import android.content.Context;
import android.util.Log;
import java.io.*;

public class RoboInstaller {
    Context ctx;

    public RoboInstaller(Context ctx) {
        this.ctx = ctx;
    }

    private static final String TAG = "RoboInstaller";

    public void installScalaLibs() {
        /*
         *  1. Make /system writeable
         *  2. Install files into application directory
         *  3. Change permissions
         *  4. Make links to ScalaLibs to /system/etc/permissions
         *  5. Make /system read-only
         */

        try {
            makeWritable();
            installFiles();
            makeLinks();
        } catch (Exception e) {
            throw new RuntimeException(e);
        } finally {
            makeReadOnly();
        }
    }

    private static void makeWritable() {
        Log.d(TAG, "Make /system writable");
        sudo("mount -oremount,rw /system");
    }

    private static void makeReadOnly() {
        Log.d(TAG, "Make /system read-only");
        sudo("mount -oremount,ro /system");
    }

    private static int[] resources = { R.raw.android_support_v4_dex, R.raw.android_support_v4_dex_desc,
            R.raw.guice_3_0_no_aop_dex, R.raw.guice_3_0_no_aop_dex_desc, R.raw.roboguice_2_0_dex,
            R.raw.roboguice_2_0_dex_desc, R.raw.javax_inject_dex, R.raw.javax_inject_dex_desc };

    private void installFiles() throws IOException {
        for (int resid : resources)
            installFile(resid);
    }

    private void makeLinks() {
        for (int resid : resources) {
            File path = fileForResource(resid);

            if (path.getName().endsWith("_desc.xml")) // descriptor
                sudo("ln -sf %s /system/etc/permissions/%s", path.getAbsolutePath(), path.getName());
        }
    }

    private static Runtime runtime = Runtime.getRuntime();

    private static void sudo(String cmdFormat, Object... args) {
        String cmd = String.format(cmdFormat, args);
        try {
            Process proc = runtime.exec(new String[] { "su", "-c", cmd });
            int res = proc.waitFor();
            if (res != 0)
                throw new RuntimeException(
                        String.format("Execution of cmd '%s' failed with exit code %d", cmd, res));
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    /**
     * Takes the resource with the given name and installs it into the files dir
     * @param resid
     */
    private void installFile(int resid) throws IOException {
        File targetFile = fileForResource(resid);
        Log.i(TAG, "Extracting file to " + targetFile.getAbsolutePath());
        FileOutputStream fos = new FileOutputStream(targetFile);
        InputStream is = ctx.getResources().openRawResource(resid);

        byte[] buffer = new byte[65000];

        while (is.available() > 0) {
            int read = is.read(buffer);
            fos.write(buffer, 0, read);
        }
        is.close();
        fos.close();

        sudo("chmod a+r " + targetFile.getAbsolutePath());
    }

    private File fileForResource(int resid) {
        String namePart = lastPart(ctx.getResources().getResourceName(resid));
        if (namePart.endsWith("_desc"))
            namePart = namePart + ".xml";
        else
            namePart = namePart + ".jar";

        return new File(ctx.getFilesDir(), namePart);
    }

    private String lastPart(String path) {
        return path.substring(path.lastIndexOf("/") + 1);
    }
}