The AFT (Autonomous FireTruck) is a prototype of an autonomous firetruck that can put out fire without risking people's lives. This project won a finalist prize in the Make with Ada 2019/20 competition.
Guillermo Perez's project won a finalist prize in the Make with Ada 2019/20 competition. This project was originally posted on Hackster.io here. For those interested in participating in the 2020/21 competition, registration is now open and project submissions will be accepted until Jan 31st 2021, register here.
Welcome to the Ada for micro:bit series where we look at simple examples to learn how to program the BBC micro:bit with Ada.
A few years ago we realized that having a package manager for the Ada/SPARK community would be a game changer. Since then, AdaCore has been sponsoring and contributing to the Alire project created by Alejandro Mosteo from the Centro Universitario de la Defensa de Zaragoza. With this blog post I want to introduce Alire and explain why this project is important for the `Ada`/`SPARK` community.
News from the Ada front The next revision of the Ada standard is now almost ready, so it's time for a status update on where GNAT and AdaCore stand on this front!
Blaine Osepchuk's project won a finalist prize in the Make with Ada 2019/20 competition. This project was originally posted on Hackster.io here. For those interested in participating in the 2020/21 competition, registration is now open and project submissions will be accepted until Jan 31st 2021, register here.
Welcome to the Ada for micro:bit series where we look at simple examples to learn how to program the BBC micro:bit with Ada.
Laurent Zhu's and Damien Grisonnet's project was accomplished for the EPITA Ada courses and won a finalist prize in the Make with Ada 2019/20 competition.
Welcome to the Ada for micro:bit series where we look at simple examples to learn how to program the BBC micro:bit with Ada.
Welcome to the Ada for micro:bit series where we look at simple examples to learn how to program the BBC micro:bit with Ada.
Welcome to the Ada for micro:bit series where we look at simple examples to learn how to program the BBC micro:bit with Ada.
Starting today, AdaCore has put in place a Code of Conduct (CoC) to ensure a positive environment for everyone willing and wanting to interact with us. With the development of this blog, our twitter accounts, and our GitHub corporate account, there is more and more communication between AdaCore and a number of communities. In this Code of Conduct we want to explain how we are going to moderate the AdaCore-maintained community spaces with the goal of maintaining a welcoming, friendly environment.
Welcome to the Ada for micro:bit series where we look at simple examples to learn how to program the BBC micro:bit with Ada.
A code obfuscator is a method of sharing coding discussions of real-world examples without giving away proprietary or classified information. This article shows an example of an Ada obfuscator, written in the SPARK language and using the Libadalang library to intelligently hide names and text within the source.
Welcome to the Ada for micro:bit series where we look at simple examples to learn how to program the BBC micro:bit with Ada.
Welcome to the Ada for micro:bit series where we look at simple examples to learn how to program the BBC micro:bit with Ada.
This is the second post of a series about GNATcoverage and source code instrumentation. The previous post introduced how GNATcoverage worked originally and why we extended it to support source instrumentation-based code coverage computation. Let’s now see it in action in the most simple case: a basic program running on the host machine, i.e. the Linux/Windows machine that runs GNATcoverage itself.
This is the first post of a series about GNATcoverage and source code instrumentation.In order to make GNATcoverage viable in more contexts, we planned several years ago to add instrumentation support in GNATcoverage for Ada sources. This feature reached maturation recently and is available in the last Continuous Release, so it is a good time to present it with a blog series!
The FACE™ approach is a government-industry initiative for reducing defense system life cycle costs through portable and reusable software components. It consists of a technical approach — a software standard based on well-defined common interfaces — and a business strategy for encouraging the development and deployment of FACE conformant products.
Hedley Rainnie's project combines 6 different SoCs all programmed in Ada performing as a LoRa network. He also showcases a BLE bridge to a LoRa server. His project came about when him and his wife were musing about how to detect and deter unwanted garden visitors. This ongoing project won a finalist prize in the 2019/20 Make with Ada competition.
SPARK always being under development, new language features make it in every release of the tool, be they previously unsupported Ada features (like access types) or SPARK specific developments. However, new features generally take a while to make it into actual user code. The feature I am going to present here is in my experience an exception, as it was used both internally and by external users before it made it into any actual release. It was designed to enhance the verification of data initialization, whose limitations have been a long standing issue in SPARK.
Shahariar's project ensures safety against electrical fire or shock during an earthquake, flood, gas leakage or fire breakout by disconnecting the mains with a smart circuit breaker. Additionally, this project won a finalist prize in the 2019/20 Make with Ada competition.
Team CryptAda's project collects entropy, manages an entropy pool, implements a homemade PRNG, and generates RSA keys directly on the board with an accent on security. Additionally, this project won a finalist prize in the 2019/20 Make with Ada competition.
John Singleton's The SmartBase makes your existing adjustable bed safer and easier to use by adding voice control and safe (and fun!) LED underbed lighting! Additionally, this project won first place prize in the 2019/20 Make with Ada competition.
Last year, I started evaluating programming languages for a formally-verified operating system. I've been developing software for a while, but only recently began work in high integrity software development and formal methods. There are several operating system projects, like the SeL4 microkernel and the Muen separation kernel, that make use of formal verification. But I was interested in using a formally-verified language to write a general-purpose OS - an environment for abstracting the underlying hardware while acting as an arbiter for running the normal applications we're used to.
We are happy to announce that the GNAT Community 2020 release is now available! Read the post for access to download and to find out about this year's release highlights.
This blog entry describes the transformation of an Ada stack ADT into a completely proven SPARK implementation that relies on static verification instead of run-time enforcement of the abstraction’s semantics. We will prove that there are no reads of unassigned variables, no array indexing errors, no range errors, no numeric overflow errors, no attempts to push onto a full stack, no attempts to pop from an empty stack, that subprogram bodies implement their functional requirements, and so on. As a result, we get a maximally robust implementation of a reusable stack abstraction providing all the facilities required for production use.
One of the most powerful features of Ada 2012* is the ability to specify contracts on your code. Contracts describe conditions that must be satisfied upon entry (preconditions) and upon exit (postconditions) of your subprogram. Preconditions describe the context in which the subprogram must be called, and postconditions describe conditions that will be adhered to by the subprogram’s implementation. If you think about it, contracts are a natural evolution of Ada’s core design principle. To encourage developers to be as explicit as possible with their expressions, putting both the compiler/toolchain and other developers in the best position to help them develop better code.
Not long ago, AdaCore published its LLVM frontend for GNAT. Also quite recently Espressif updated their LLVM backend to LLVM 9 which also happens to be the LLVM version of GNAT. This gave me to the idea to try out if LLVMs promise of providing modular and reusable toolchain technologies is true.
For an upcoming project, I needed a simple way of transferring binary files over an Ethernet connection with minimal (if any at all) user interaction. A protocol that's particularly appropriate for this kind of usage is the Trivial File Transfer Protocol (TFTP).
Over the last few months, I developed a SPARK version of the TweetNaCl cryptographic library. This was made public on GitHub in February 2020, under the 2-clause BSD licence. This blog entry goes into a bit more technical detail on one particular aspect of the project: the challenge of re-writing and verifying "constant time" algorithms using SPARK.
Learn how to use GDB and RR's advanced time traveling features in GNAT Studio.
Having previously shown how to create a Web application in Ada, it's not so difficult to create an Android application in Ada. Perhaps the simplest way is to install Android Studio. Then just create a new project and choose "Empty Activity". Open the layout, delete TextView and put WebView instead.
As a demonstration for the use of Ada and SPARK in very small embedded targets, I created a remote-controlled (RC) car using Lego NXT Mindstorms motors and sensors but without using the Lego computer or Lego software. I used an ARM Cortex System-on-Chip board for the computer, and all the code -- the control program, the device drivers, everything -- is written in Ada. Over time, I’ve upgraded some of the code to be in SPARK. This blog post describes the hardware, the software, the SPARK upgrades, and the repositories that are used and created for this purpose.
Martyn’s recent blog post showed small programs based on Libadalang to find uses of access types in Ada sources. Albeit short, these programs need to take care of all the tedious logistics around processing Ada sources: find the files to work on, create a Libadalang analysis context, use it to read the source files, etc. Besides, they are not very convenient to run:
The GNAT-LLVM project provides an opportunity to port Ada to new platforms, one of which is WebAssembly. We conducted an experiment to evaluate the porting of Ada and the development of bindings to use Web API provided by the browser directly from Ada applications.
Like last year and the year before, AdaCore will participate to the celebration of Open Source software at FOSDEM. It is always a key event for the Ada/SPARK community and we are looking forward to meet Ada enthusiasts. You can check the program of the Ada/SPARK devroom here.
I was quite happy to see AdaFruit release their first Feather format board including a micro-controller with plenty of Ada support, the STM32F4. I bought a board right away and implemented some support code for it.
For nearly four decades the Ada language (in all versions of the standard) has been helping developers meet the most stringent reliability, safety and security requirements in the embedded market. As such, Ada has become an entrenched player in its historic A&D niche, where its technical advantages are recognized and well understood. Ada has also seen usage in other domains (such as medical and transportation) but its penetration has progressed at a somewhat slower pace. In these other markets Ada stands in particular contrast with the C language, which, although suffering from extremely well known and documented flaws, remains a strong and seldom questioned default choice. Or at least, when it’s not the choice, C is still the starting point (a gateway drug?) for alternatives such as C++ or Java, which in the end still lack the software engineering benefits that Ada embodies..
What's changed?In 2019 AdaCore created a UK business unit and embarked on a new and collaborative venture researching and developing advanced UK aerospace systems. This blog introduces the reader to ‘HICLASS’, describes our involvement and explains how participation in this project is aligned with AdaCore’s core values.
I’ve been telling Ada developers for a while now that Libadalang will open up the possibility of more-easily writing Ada source code analysis tools. (You can read more about Libadalang here and here and can also access the project on Github.)
Handling binary data is hard. Errors in parsers routinely lead to critical security vulnerabilities. In this post we show how the RecordFlux toolset eases the creation of formally verified binary parsers in SPARK.
Part of our core expertise at AdaCore is to integrate multiple technologies as smoothly as possible and make it a product. This started at the very beginning of our company by integrating a code generator (GCC) with an Ada front-end (GNAT) which was then followed by integrating a debugger engine (GDB) and led to today's rich GNAT Pro offering.
How I learned to write SPARK-provable code using Conway's Game Of Life
As seen in a previous post, it is possible to use pointers (or access types) in SPARK provided the program abides by a strict memory ownership policy designed to prevent aliasing. We will show in this post how to define pointer-based data-structures in SPARK and how to traverse them without breaking the ownership policy.
Presenting the GNAT LLVM projectAt AdaCore labs, we have been working for some time now on combining the GNAT Ada front-end with a different code generator than GCC.
AdaCore’s fourth annual Make with Ada competition launched this week with over $8K in cash and prizes to be awarded for the most innovative embedded systems projects developed using Ada and/or SPARK.
The Ada Community has gathered recently around a new exciting initiative - an Ada Virtual Conference, to present Ada-related topics in a 100% remote event. The first such conference took place on August, 10th 2019, around the topic of the new features in Ada 202x. Here is what was presented.
The challenge faced by cryptography APIs is to make building functional and secure programs easy for the user. In this blog post I will present you how I created a SPARK binding for Libsodium, using strong typing and preconditions/postconditions to enforce a safe and functional use of basic cryptographic primitives.
The functionality of many security-critical programs is directly related to Input/Output (I/O). This includes command-line utilities such as gzip, which might process untrusted data downloaded from the internet, but also any servers that are directly connected to the internet, such as webservers, DNS servers and so on. In this blog post we show an approach that deals with error handling and reasoning about content, and demonstrate the approach using the cat command line utility.