[Android-NDK] Creating shared library and using them in Android Oreo 8 and 8.1

Posted by Pranav Pareek on Apr 4, 2019 in Android, Blog | 430 comments

In this post I’m going to show how to build shared library for android and using them. I’m using Ubuntu 16.04 LTS running inside a VM and Android Studio 3.2.1 running on windows 10.

Step1: Setting up the environment

• Get Android NDK (https://developer.android.com/ndk/downloads). At the time of writing this post I’m using android-ndk-r19c-linux-x86_64.zip
• Unizp the downloaded file and change directory into android-ndk-r19c. In this directory you should see a binary called “ndk-build”. We will use this binary to build the shared library.

JCov Tutorial | Coverage tool installation and simple use case

Posted by Pranav Pareek on Oct 13, 2016 in Uncategorized | 299 comments

This tutorial is intended to help on how to build JCov and demonstrate a simple use case. This tutorial is for Ubuntu.

First Step in to install Java, in my case I have installed Java 8. Below are the command to install.

• sudo add-apt-repository ppa:openjdk-r/ppa
• sudo apt-get update
• sudo apt-get install openjdk-8-jdk
• sudo apt-get install openjdk-8-jre

Next step is to install apache ant and mercurial. Use the below commands to install:

• sudo apt-get install ant
• sudo apt-get install mercurial

Next download asm framework and JT Harness from the below url, these two are required to build JCov

Asm framework: wget http://download.forge.ow2.org/asm/asm-5.0.1-bin.zip

JT Harness: wget https://adopt-openjdk.ci.cloudbees.com/job/jtharness/lastSuccessfulBuild/artifact/jtharness-4.6.tar.gz

Extract asm-5.0.1-bin.zip and jtharness-4.6.tar.gz

In my setup Asm framework and JT Harness were downloaded and extracted at /home/test therefore my path for Asm framework is /home/test/asm-5.0.1/lib/all/asm-all-5.0.1.jar and for JT Harness /home/test/javatest/lib/javatest.jar

Next we need to clone JCov repo, use the below command to clone the repo

• hg clone http://hg.openjdk.java.net/code-tools/jcov

Now we have installed all the dependencies and ready to build JCov. Go to jcov/build directory and use the below commands. Don’t forget to replace your path for Asm framework and JT Harness in the command.

• ant clean
• ant -v -f build.xml -Dasmjar5=/home/test/asm-5.0.1/lib/all/asm-all-5.0.1.jar -Djavatestjar=/home/test/jtharness/lib/javatest.jar

This should build JCov, now lets test JCov with a sample use case, save the below code as Hello.java:

public class Hello {

public static void main(String[] argv) {

System.out.println(“Hello World”);

}

}

•    Compile using java

    javac Hello.java

•    Instrument it

    java -jar /home/test/jcov/JCOV_BUILD/jcov_3.0/jcov.jar Instr Hello.class

    This step should generate template.xml file

•    Run it

    java -classpath .:/home/test/jcov/JCOV_BUILD/jcov_3.0/jcov_file_saver.jar Hello

    Hello can be replace with the test case class. This step should generate result.xml

•    Generate report

    java -jar /home/test/jcov/JCOV_BUILD/jcov_3.0/jcov.jar RepGen -o report result.xml

Report should be created in report folder. Open it using the below command:

    xdg-open report/index.html

In a similar way jar files can also be instrumented, in the instrumentation step just replace Hello.class file with the desired jar. If you want code highlighting available then you may need to pass -src flag during report generation. Below is an example:

java -jar /home/test/jcov/JCOV_BUILD/jcov_3.0/jcov.jar RepGen -src /home/test/workspace/Hello/src/ -o report result.xml

Logstash JSON filter to detect events

Posted by Pranav Pareek on Jan 6, 2016 in Blog | 36 comments

I wanted to filter out JSON encoded data coming from OSSEC client to logstash and then forward the parsed JSON to clients connected over websocket. This filter could be useful for detecting and sending alerts on occurrence of certain events, so I wrote a filter to parse only the JSON encoded data and discard any other data.

PIC32 and ILI9328 TouchScreen User Interface using Microchip Graphic Library

Posted by Pranav Pareek on Feb 12, 2015 in Blog | 0 comments

I developed this user interface (UI) using pic32, microchip GDD tool and microchip graphic library.

I recorded the test in this video

Testing ILI9328 2.8″ TFT (Touch Screen) with PIC32MX795F512L

Posted by Pranav Pareek on Feb 10, 2015 in Blog | 28 comments

performed a simple test to interface ILI9328 2.8″ TFT (Touch Screen) with PIC32MX795F512L, later on I also wrote SPI based touchscreen driver for analog devices ADS7843. The main program checks for the data available pin and if touchscreen data is available it reads through SPI:

Testing Texas Instruments keyfob (CC2540) with custom android app

Posted by Pranav Pareek on Jan 24, 2015 in Blog | 30 comments

I build a test android app to communicate with Bluetooth Low Energy keyfob CC2541 kit from Texas Instruments.

The end project was to design and develop a small size anti-theft/forget device and mobile phone application which can communicate with the device. This device can be placed inside wallet, briefcase, etc  and on link loss the app can alert mobile phone user about lost item. And device should be able to run on a coin cell for duration of 8-12months.

During Schematic and PCB design I also added accelerometer and intervalometer for future application. Unfortunately the project never got off the ground but app and PCB was designed and developed.

inductor, capacitor and resistors used were 0201 size.

intervalometer for taking picture on phone using the device.

MCP3208 A/D converter on Pinguino 18F2550

Posted by Pranav Pareek on Jun 26, 2013 in Blog | 34 comments

If you are working on Pinguino and want to use MPC3208 ADC for reading analog sensors then the following code will be helpful to you. This code is based on arduino example, I have ported it to pinguino 18F2550.