by AdaCore Admin –
Introducing the Make With Ada competition!
If you’ve been looking for a way to start your next embedded project in Ada or SPARK. Then, look no further than the Make with Ada competition!
If you’ve been looking for a way to start your next embedded project in Ada or SPARK. Then, look no further than the Make with Ada competition!
I recently started working on an Ada binding for the excellent libuv C library. This library provides a convenient API to perform asynchronous I/O under an event loop, which is a popular way to develop server stacks. A central part of this API is its enumeration type for error codes: most functions use it. Hence, one of the first things I had to do was to bind the enumeration type for error codes. Believe it or not: this is harder than it first seems!
I started this project more than a year ago. It was supposed to be the first Make with Ada project but it became the most challenging from both, the hardware and software side.
AdaCore provides several tools with certification and qualification capabilities, for the rail and avionics industry. Quentin Ochem’s presentation on “Certification and Qualification” at the 2015 AdaCore Tech Days in Boston, Massachusetts provided more information about these two standards, namely DO-178C and EN:50128:2011.
As seen in the previous blog article, AdaCore relies heavily on virtualisation to perform the testing of its GNAT Pro products for VxWorks.
We are pleased to announce that on April 27th our partner, Vector, will host a webinar to showcase their latest VectorCAST/Ada release!
AdaCore continues to build reliable and secure software for embedded software development tools. Last month, we attended Embedded World 2016, one of the largest conferences of its kind in Europe, to present our embedded solutions and our expertise for safety, and mission critical applications in a variety of domains.
Dr Carl Brandon of Vermont Technical College and his team of students used SPARK and Ada to successfully launch a satellite into space in 2013 and it has continued to orbit the Earth ever since! At our AdaCore Tech Days in Boston last year Dr Brandon explained further.
Just a few weeks ago, one of our partners reported a strange behavior of the well-known function Ada.Text_IO.Get_Line, which reads a line of text from an input file. When the last line of the file was of a specific length like 499 or 500 or 1000, and not terminated with a newline character, then Get_Line raised an exception End_Error instead of returning the expected string. That was puzzling for a central piece of code known to have worked for the past 10 years! But fair enough, there was indeed a bug in the interaction between subprograms in this code, in boundary cases having to do with the size of an intermediate buffer. My colleague Ed Schonberg who fixed the code of Get_Line had nonetheless the intuition that this particular event, finding such a bug in an otherwise trusted legacy piece of code, deserved a more in depth investigation to ensure no other bugs were hiding. So he challenged the SPARK team at AdaCore in checking the correctness of the patched version. He did well, as in the process we uncovered 3 more bugs.
A few months ago, my colleague Rebecca installed a candy dispenser in our kitchen here at AdaCore. I don’t remember how exactly, but I was challenged to make it more… fun.
Embedded products are not stand alone, this allows them to have safety, mission critical and real-time requirements that they wouldn’t necessarily have otherwise. The embedded product line provides analyzable, verifiable, and certifiable software for both static and dynamic analysis tools.
Embedded World will see the latest release of QGen, the qualifiable and customisable code generator for Simulink® and Stateflow® models!
We are pleased to announce our latest release of SPARK Pro! A product that has been jointly developed alongside our partner Altran and following the global AdaCore Tech Days, you can now see the SPARK 2014 talk, Formal Verification Made Easy by AdaCore’s Hristian Kirtchev, on YouTube.
We are pleased to announce that we will be a major sponsor and exhibitor at ERTS, Toulouse and will be exhibiting at Embedded World, Nuremberg in the coming months!
A step by step tutorial to adapt the ARM runtime to new MCUs/boards.
The three of us attended the Ada Lovelace Symposium in Oxford (UK). The two days were one fantastic discovery after another about the life, achievements and legacy of Ada Lovelace, the programming pioneer who lent her name to the Ada language.
Frederick Pothon of ACG Solutions has recently published a document entitled - Dissimilar tools: Use cases and impact on tool qualification level on the open-DO blog.
This short post describes an idiom that can be used to help maintain complex hierarchies of tagged types, when methods need to call the parent types methods.
When the Pebble Time kickstarter went through the roof, I looked at the specification and noticed the watch was running on an STM32F4, an ARM cortex-M4 CPU which is supported by GNAT. So I backed the campaign, first to be part of the cool kids and also to try some Ada hacking on the device.
Through the adoption of GitHub we have taken our first step on the way to having a more collaborative and dynamic interaction with, both our users and open source technologies.
We are continuing to develop tools for use within projects that require reliable and secure embedded software for ARM. Our engineering team have been busy creating demos running on ARM technology, such as Tetris in SPARK on ARM Cortex M4.
The Ada 2012 standard introduced user-defined references. The main idea behind this is simplifying the access to elements in a container. But you can use them to control the life-circle of your persistent objects. Let's see how it could work.
We are excited to be sponsoring and exhibiting at the 2nd annual High Integrity Software conference, taking place on 5th November 2015 at The Royal Marriott Hotel in Bristol.
This post describes the design of a new containers library. It highlights some of the limitations of the standard Ada containers, and proposes a new approach using generic packages as formal parameters to make these new containers highly configurable at compile time.
If you're somewhat interested in formal methods applied to software, but you never had the chance to really look at it, now is the time! Prof. John McCormick from University of Northern Iowa and Prof. Peter Chapin from Vermont Technical College have written a truly essential book for getting up to speed with formal verification using SPARK. I really love this book, and here are the aspects I love most:
I started out as an electronic musician, so one of my original motivations when I learnt programming was so that I could eventually *program* the sounds I wanted rather than just use already existing software to do it.
AdaCore has a long history of providing tools and support to develop mission critical applications for Space. Check out this video we made and showed at the conference to see which ones!
July 20, 1969, 8:18 p.m. UTC, while a bunch of guys were about to turn blue on Earth, commander Neil A. Armstrong confirms the landing of his Lunar Module (LM), code name Eagle, on the moon. Will you be able to manually land Eagle on the Sea of Tranquillity?
It is with great sadness that I have to announce the death of Robert Dewar...
A few weeks ago I discovered the wonderful world of solenoid engines. The idea is simple: take a piston engine and replace explosion with electromagnetic field. In this article I will experiment a solenoid engine using a hacked hard drive and a software controller on a STM32F4 .
The Crazyflie is a very small quadcopter sold as an open source development platform: both electronic schematics and source code are directly available on their GitHub and its architecture is very flexible. Even if the Crazyflie flies out of the box, it has not been developed with safety in mind: in case of crash, its size, its weight and its plastic propellers won’t hurt anyone! But what if the propellers were made of carbon fiber, and shaped like razor blades to increase the drone’s performance? In theses circumstances, a bug in the flight control system could lead to dramatic events. In this post, I present the work I did to rewrite the stabilization system of the Crazyflie in SPARK 2014, and to prove that it is free of runtime errors. SPARK also helped me to discover little bugs in the original firmware, one of which directly related with overflows. Besides the Crazyflie, this work could be an inspiration for others to do the same work on larger and more safety-critical drones.
Reference countingReference counting is a way to automatically reclaim unused memory. An element is automatically deallocated as soon as there are no more references to it in the program.
This post shows how to implement a special storage pool that allocates an extra header every time it allocates some memory. This can be used to store type specific information, outside of the type itself.
Forget about the black box - we want you to see what's in the AdaCore box! Our machine room, the life blood of the company, is centered in the office space in a glass box and is pure eye candy for geeks and cable aficionados. The machine room is 204 sq ft (19 sq meters), contains 73 machines (running the gamut from VxWorks, Linux, Windows, Android and more) 1.5 miles of cables and a state of the art fire suppression mechanism! Oh and the modern air intake system gives it a green energy seal of approval. In the unlikely event of a fire; the smoke detectors allow 30 seconds before dispersing an agent called FM200 which will suppress the fire but not damage the equipment. The economizer takes advantage of winters' freeze and draws cool air from the outside to cool the machine room and the heated air is then spilled to common office areas thus reducing heating costs. We're proud to show-off the hardware side of our software!
Project-P Open Workshop
One of the main challenges to get certification in Ada projects is the achievement of 100% code coverage but in most projects an amount of more than 95% structural coverage is hard to achieve. What can you do with the last 5% of code that can't be covered? DO-178C for example, provides a framework for the integration of various techniques in the development process to solve the problem. In this webinar you learn how static analysis and dynamic testing can help complete analysis for pieces of code that are not covered.
Despite her famously sharp analytical mind, it’s unlikely Ada Lovelace could have predicted the durability of her legacy as the world’s first computer programmer and pioneer for women in computing.
Following the terrorist attacks that occurred in Paris earlier this year, the French government is proposing a bill that will, supposedly, improve the control over intelligence services and give legal ground to some of the intelligence-gathering methods these services are already known to use, ie. render legal, the previously illegal, Internet wiretapping. Interestingly, opponents of the this time bill include not only the usual civil liberty activists such as La Quadrature du Net, Amnesty International or La ligue des droits de l’Homme. Professional trade unions, such as Syntec, companies, such as OVH and even official bodies, such as the CNIL and the Défenseur des droits also expressed an unusually vocal opposition to the proposed bill.
I recently joined AdaCore as a Technical Account Manager with an initial focus on the UK and Scandinavian regions, but for the last 12 months I've been busy working on the AdaCore University. The most recent addition to which is a course on Mixed Language Programming with Ada, and it includes lectures on the integration of Ada with C, C++ and Java. The course covers some advanced topics like mixed language object orientation, techniques for using Ada strong typing to combat known issue with C pointers and the pitfalls that are encountered when mixing native Ada code with Java at runtime. This course clearly demonstrates that Ada has strong support for integration with C, C++ and Java and it proves there are no technical barriers to its adoption in modern mixed language software systems.
In a recent article in Communications of the ACM, Carl Landwehr, a renowned scientific expert on security, defends the view that the software engineering community is doing overall a poor job at securing our global information system and that this is mostly avoidable by putting what we know works to work, to the point that most vulnerabilities could be completely avoided by design if we cared enough. Shocking! Or so it should appear.
Embedded News TV caught up with our own Matteo Bordin to talk about QGen. Matteo provides a nice overview of QGen and it's position in the industry as the need for safe and secure software becomes increasingly important.
20 Years of AdaCore: Company as Committed as Ever on Safety-Critical Software Solutions
February saw the annual customer release of a number of important products. This is no mean task when you consider the fact that GNAT Pro is available on over 50 platforms and supports over 150 runtime profiles (ranging from Full Ada Support to the very restricted Zero Footprint Profile suitable for safety-critical development). All in all, from the branching of the preview version to the customer release it takes us nearly 4 months to package everything up! Quality is assured through the internally developed AdaCore Factory.
I've recently written an article (in two parts) over at Electronic Design about applying different methods of verification to the same small piece of code. The code in question is an implementation of binary search, and I applied Testing, Static Analysis (using the AdaCore tool CodePeer) and Formal Verification (using the AdaCore tool SPARK 2014).
I was at Bruxelles on January 31st to present the components of GNAT GPL 2015 : SPARK 2014 and GNAT GPL for ARM bare-board. This is not unrelated to a previous blog entry on Tetris in SPARK on ARM Cortex M4, in particular I presented that Tetris demo (I brought some boards with me and despite the simple package, none were broken!). The slides contain technical details on the ravenscar profile (main principles), how to build a program for the stm32f4-discovery board and how to port the runtime. There are also less technical slides such as why we choose the stm32f4 board and photos of some graphical demos. As that could be useful to anyone interested in Ravenscar or in porting the runtime to other boards or other platforms, we've made the slides available here.
For lovers of verification tools and critical system (we know you're out there!), we are very excited to present ProofInUse!
If you have a passion for Ada, need more information on our technology or would just like to have a chat, there are a couple of upcoming events where we'd love to meet up. What's more, we'll be launching our brand new product QGen at Embedded World!
Tetris is a well-known game from the 80's, which has been ported in many versions to all game platforms since then. There are even versions of Tetris written in Ada. But there was no version of Tetris written in SPARK, so we've repaired that injustice. Also, there was no version of Tetris for the Atmel SAM4S ARM processor, another injustice we've repaired.
I'm proud, if not a bit nervous, to be the one firing the very first post on this brand new blog. Why are we starting a corporate blog at this time? There are many reasons for this. The main one is that there are many things happening at AdaCore and around the GNAT technology and we are seeking better ways to make them widely known while offering interested recipients the possibility to react and interact with us.