Open source *

Hello everyone!

Today I'm going to tell about how is test task to job interview became the library Image Comparison. It's an open-source library, which is hosting on GitHub.



Before I start, let me introduce myself. My name is Roman. I'm a husband and father. I'm a software engineer in Epam Systems with 4 years of experience in IT.

The main idea of this topic is to tell, that creating an open-source product it's not wasting time, no! It's an amazing experience, which is going from all the open-source community. It's a time when you're a developer, project manager, product manager in one head.

While this library is growing I have been working with people from more than 10(!!) countries, such as the USA, Germany, Chine, India, Russia, Ukraine, etc.

Let's move on from the start of this story…

Codes are the blocks of instructions that convey your intention to the computer. It is coding that helps you get the best out of the machines. Thus every, program or software is a creation of codes and the way they are structured and written defines the specialty of that software.

Anyone who programs microcontrollers probably knows about FreeRTOS, or at least heard of this operating system. Amazon developers decided to enhance the abilities of this operating system to work with AWS Internet of Things services. This is how Amazon FreeRTOS appeared. We, developers of the PVS-Studio static code analyzer, were asked by mail and in comments to check these projects. Well, now get what you asked for. Keep reading to find out what came out of it.

I've been talking about it for months, but in case you haven't heard, there's a new Windows Terminal in town. You can download it and start using it now from the Windows Store. It's free and open source.

At the time of this writing, Windows Terminal is around version 0.5. It's not officially released as a 1.0 so things are changing all the time.

Here's your todo - Have you installed the Windows Terminal before? Have you customize your profile.json file? If so, I want you to DELETE your profiles.json!

While Stockholm was holding the 118th Nobel Week, I was sitting in our office, where we develop the PVS-Studio static analyzer, working on an analysis review of the ROOT project, a big-data processing framework used in scientific research. This code wouldn't win a prize, of course, but the authors can definitely count on a detailed review of the most interesting defects plus a free license to thoroughly check the project on their own.

Introduction

ROOT is a modular scientific software toolkit. It provides all the functionalities needed to deal with big data processing, statistical analysis, visualisation and storage. It is mainly written in C++. ROOT was born at CERN, at the heart of the research on high-energy physics. Every day, thousands of physicists use ROOT applications to analyze their data or to perform simulations.

Telegram Open Network (TON) is a platform by the same team that developed the Telegram messenger. In addition to the blockchain, TON provides a large set of services. The developers recently made the platform's code, which is written in C++, publicly available and uploaded it to GitHub. We decided to check the project before its official release.

Celestia is a three-dimensional space simulator. Simulation of the space allows exploring our universe in three dimensions. Celestia is available on Windows, Linux and macOS. The project is very small and PVS-Studio detected few defects in it. Despite this fact, we'd like to pay attention to it, as it's a popular educational project and it will be rather useful to somehow improve it. By the way, this program is used in popular films, series and programs for showing space. This fact, in turns, raises requirements to the code quality.

The adventures with the Mozilla Thunderbird mail client began with automatic update to version 68.0. More text in pop-up notifications and default dark theme are the notable features of this version. Occasionally I found an error that I immediately craved to detect with static analysis. This became the reason to go for another check of the project source code using PVS-Studio. It so happened that by the time of the analysis, the bug had already been fixed. However, since we've paid some attention to the project, there's no reason not to write about other found defects.

Introduction

The dark theme of the new Thunderbird version looks pretty. I like dark themes. I've already switched to them in messengers, Windows, macOS. Soon iPhone will be updated to iOS 13 with a dark theme. For this reason I even had to change my iPhone 5S for a newer model. In practice, it turned out that a dark theme requires more effort for developers to pick up the colors of the interface. Not everyone can handle it the first time.

Deep Learning applications have changed a lot of things. Some which give hope for a brighter future, and some which raise suspicions. However, for developers, the growth of deep learning applications has made them more perplexed about choosing the best among so many deep learning frameworks out there.

TensorFlow is one of the deep learning frameworks that comes in mind. It is arguably the most popular deep learning framework out there. Nothing justifies the statement better than the fact that Tensorflow is used by the likes of Uber, Nvidia, Gmail among other big corporations for developing state-of-the-art deep learning applications.

But right now, I am on a quest to find whether it indeed is the best deep learning framework. Or perhaps find what makes it the best out of all other frameworks it competes against.

MIDI player

• Use MIDI parser to read notes from MIDI file
• Use WebAudioFont to play musical instruments in a browser
• See result

Apache Dubbo is one of the most popular Java projects on GitHub. It's not surprising. It was created 8 years ago and is widely applied as a high-performance RPC environment. Of course, most of the bugs in its code have long been fixed and the quality of the code is maintained at a high level. However, there is no reason to opt out of checking such an interesting project using the PVS-Studio static code analyzer. Let's see how it turned out.

Travis CI is a distributed web service for building and testing software that uses GitHub as a source code hosting service. In addition to the above scripts, you can add your own, thanks to the extensive configuration options. In this article we will set up Travis CI for working with PVS-Studio by the example of PPSSPP code.

Surely you've heard the expression «bug hunting» many times. I dare to assume, you won't mind earning one or two hundred (or even thousand) dollars by finding a potential vulnerability in someone's program. In this article, I'll tell you about a trick that will help analyzing open source projects in order to find such vulnerabilities.

CMake is a cross-platform system for automating project builds. This system is much older than the PVS-Studio static code analyzer, but no one has tried to apply the analyzer on its code and review the errors. As it turned out, there are a lot of them. The CMake audience is huge. New projects start on it and old ones are ported. I shudder to think of how many developers could have had any given error.

For the past ten years, the open-source movement has been one of the key drivers of the IT industry's development, and its crucial component. The role of open-source projects is becoming more and more prominent not only in terms of quantity but also in terms of quality, which changes the very concept of how they are positioned on the IT market in general. Our courageous PVS-Studio team is not sitting idly and is taking an active part in strengthening the presence of open-source software by finding hidden bugs in the enormous depths of codebases and offering free license options to the authors of such projects. This article is just another piece of that activity! Today we are going to talk about Apache Hive. I've got the report — and there are things worth looking at.

.NET Core libraries is one of the most popular C# projects on GitHub. It's hardly a surprise, since it's widely known and used. Owing to this, an attempt to reveal the dark corners of the source code is becoming more captivating. So this is what we'll try to do with the help of the PVS-Studio static analyzer. What do you think – will we eventually find something interesting?

This is a short story about how PVS-Studio helped us find an error in the source code of the library used in PVS-Studio. And it was not a theoretical error but an actual one — the error appeared in practice when using the library in the analyzer.

Nowadays there is no need to implement the physics of objects from scratch for game development because there are a lot of libraries for this purpose. Bullet was actively used in many AAA games, virtual reality projects, various simulations and machine learning. And it is still used, being, for example, one of the Red Dead Redemption and Red Dead Redemption 2 engines. So why not check the Bullet with PVS-Studio to see what errors static analysis can detect in such a large-scale physics simulation project.

Our attention was recently attracted by the Electronic Arts repository on GitHub. It's tiny, and of the twenty-three projects available there, only a few C++ libraries seemed interesting: EASTL, EAStdC, EABase, EAThread, EATest, EAMain, and EAAssert. The projects themselves are tiny too (about 10 files each), so bugs were found only in the «largest» project of 20 files :D But we did find them, and they do look interesting! As I was writing this post, we were also having a lively discussion of EA games and the company's policy :D

Numerous typos and Copy-Paste code became the main topic of the additional article about checking the Haiku code by the PVS-Studio analyzer. Yet this article mostly tells about errors related to thoughtlessness and failed refactoring, rather than to typos. The errors found demonstrate how strong the human factor is in software development.