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The software heritage of K&R C

Derek Jones from The Shape of Code

The mission statement of the Software Heritage is “… to collect, preserve, and share all software that is publicly available in source code form.”

What are the uses of the preserved source code that is collected? Lots of people visit preserved buildings, but very few people are interested in looking at source code.

One use-case is tracking the evolution of changes in developer usage of various programming language constructs. It is possible to use Github to track the adoption of language features introduced after 2008, when the company was founded, e.g., new language constructs in Java. Over longer time-scales, the Software Heritage, which has source code going back to the 1960s, is the only option.

One question that keeps cropping up when discussing the C Standard, is whether K&R C continues to be used. Technically, K&R C is the language defined by the book that introduced C to the world. Over time, differences between K&R C and the C Standard have fallen away, as compilers cease supporting particular K&R ways of doing things (as an option or otherwise).

These days, saying that code uses K&R C is taken to mean that it contains functions defined using the K&R style (see sentence 1818), e.g.,

writing:

int f(a, b)
int a;
float b;
{
/* declarations and statements */
}

rather than:

int f(int a, float b)
{
/* declarations and statements */
}

As well as the syntactic differences, there are semantic differences between the two styles of function definition, but these are not relevant here.

How much longer should the C Standard continue to support the K&R style of function definition?

The WG14 committee prides itself on not breaking existing code, or at least not lots of it. How much code is out there, being actively maintained, and containing K&R function definitions?

Members of the committee agree that they rarely encounter this K&R usage, and it would be useful to have some idea of the decline in use over time (with the intent of removing support in some future revision of the standard).

One way to estimate the evolution in the use/non-use of K&R style function definitions is to analyse the C source created in each year since the late 1970s.

The question is then: How representative is the Software Heritage C source, compared to all the C source currently being actively maintained?

The Software Heritage preserves publicly available source, plus the non-public, proprietary source forming the totality of the C currently being maintained. Does the public and non-public C source have similar characteristics, or are there application domains which are poorly represented in the publicly available source?

Embedded systems is a very large and broad application domain that is poorly represented in the publicly available C source. Embedded source tends to be heavily tied to the hardware on which it runs, and vendors tend to be paranoid about releasing internal details about their products.

The various embedded systems domains (e.g., 8, 16, 32, 64-bit processor) tend to be a world unto themselves, and I would not be surprised to find out that there are enclaves of K&R usage (perhaps because there is no pressure to change, or because the available tools are ancient).

At the moment, the Software Heritage don’t offer code search functionality. But then, the next opportunity for major changes to the C Standard is probably 5-years away (the deadline for new proposals on the current revision has passed); plenty of time to get to a position where usage data can be obtained 🙂

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Unborking the ISSO comments system and making it more resilient

Timo Geusch from The Lone C++ Coder's Blog

First, I apologise for not noticing that the comments had been broken for a while. This was entirely my fault and not fault of ISSO, which I’m still super happy with as a self-hosted comments system. So in this post I’m going to describe what went wrong, and also how I made the system a little more resilient at the same time. First, what did go wrong? My web server is using FreeBSD as its OS, with a bunch of software installed via FreeBSD’s ports system.
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Streaming to Twitch and PeerTube simultaneously using nginx on Oracle cloud

Andy Balaam from Andy Balaam's Blog

Simulcasting RTMP using NGINX

I want people to be able to watch my Matrix and Rust live coding streams using free software, so I’d like to simulcast to PeerTube as well as Twitch.

This is possible using NGINX and its RTMP module. It does involve building NGINX from source, but I actually found that reasonably easy to do.

Why Oracle cloud?

I would never recommend using Oracle for anything, but they do provide up to two virtual machines in their cloud for free, and the one I am using has been consistently available with very good connectivity, in a London data centre since I set it up several months ago.

So, we are making our lives more difficult by trying to do this on Oracle Linux, which is a derivative of RHEL.

Building NGINX and its RTMP module on Oracle Linux

I ran these commands on my Oracle cloud instance (running Oracle Linux):

sudo yum install git pcre-devel openssl-devel
mkdir nginx
cd nginx
wget http://nginx.org/download/nginx-1.21.4.tar.gz
git clone https://github.com/arut/nginx-rtmp-module.git
cd nginx-1.21.4
./configure --add-module=../nginx-rtmp-module/
make
sudo make install

After all this NGINX was installed to /usr/local/nginx/.

Creating the NGINX config file for RTMP simulcasting

Next I edited the NGINX config file by typing:

sudo nano /usr/local/nginx/conf/nginx.conf

And pasted in this config at the bottom of the file:

rtmp {
    server {
        listen 1935;
        chunk_size 4096;
        application live {
            live on;
            record off;
            push rtmp://live.twitch.tv/app/live_INSERT_TWITCH_STREAM_KEY;
            push rtmp://diode.zone:1935/live/INSERT_PEERTUBE_STREAM_KEY;
        }
    }
}

Notice that you will need to get your Twitch stream key from Twitch -> Creator Dashboard -> Settings -> Stream, then Copy next to the Primary Stream Key.

To get a PeerTube stream ID, you will need to go to your PeerTube page and click Publish, then Go Live, choose your channel and choose Go Live. Note that if you want the streams to record and be available later, you have to create a new stream key each time you start a stream, and change it in nginx.conf.

If you use a different PeerTube server (I use diode.zone) then you’ll need to change the server name in the config file above too.

Make sure your config file is saved with the right URLs in it.

Opening ports

To send RTMP traffic to my server, I needed to open the right port to the Oracle cloud instance. That involved creating an ingress rule, and adding a firewall rule.

Creating an ingress rule

In the web interface, I went to the menu in the top left, clicked Compute, then Instances.

I clicked on my instance’s name, then I clicked on the name of the subnet in the details (on the right).

I clicked on Default security list for…, then Add Ingress Rules.

I made an ingress rule with Source Type=CIDR, Source CIDR=0.0.0.0/0, IP Protocol=TCP, Source Port Range=(blank, meaning all), Destination Port Range=1935

Adding a firewall rule

Then I ssh’d into the machine and ran these commands to create a firewall rule allowing the traffic:

sudo firewall-cmd --zone=public --permanent --add-port=1935/tcp
sudo firewall-cmd --reload

Stop and Start NGINX

After creating the config file and opening the right port, I needed to start NGINX.

Every time I change the config file, I need to restart it.

If it’s already running, I stop it with:

sudo /usr/local/nginx/sbin/nginx -s stop

and then I start it up again with

sudo /usr/local/nginx/sbin/nginx

I can check whether it’s happy by looking at the log files, for example to see any errors:

less /usr/local/nginx/logs/error.log

Starting the stream

Now I go into OBS and go to File -> Settings -> Stream and choose the type as Custom, and the Server as rtmp://1.1.1.1/live. (But instead of 1.1.1.1 I put the public IP address of my instance, which I found by clicking the name of the instance in the Oracle cloud management console.)

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Open source: the goody bag for software infrastructure

Derek Jones from The Shape of Code

For 70 years there has been a continuing discovery of larger new ecosystems for new software to grow into, as well as many small ones. Before Open source became widely available, the software infrastructure (e.g., compilers, editors and libraries of algorithms) for these ecosystems had to be written by the pioneer developers who happened to find themselves in an unoccupied land.

Ecosystems may be hardware platforms (e.g., mainframes, minicomputers, microcomputers and mobile phones), software platforms (e.g., Microsoft Windows, and Android), or application domains (e.g., accounting and astronomy)

There are always a few developers building some infrastructure project out of interest, e.g., writing a compiler for their own or another language, or implementing an editor that suites them. When these projects are released, they have to compete against the established inhabitants of an ecosystem, along with other newly released software clamouring for attention.

New ecosystems have limited established software infrastructure, and may not yet have attracted many developers to work within them. In such ‘virgin’ ecosystems, something new and different faces less competition, giving it a higher probability of thriving and becoming established.

Building from scratch is time-consuming and expensive. Adapting existing software systems speeds things up and reduces costs; adaptation also has the benefit of significantly reducing the startup costs when recruiting developers, i.e., making it possible for experienced people to use the skills acquired while working in other ecosystems. By its general availability, Open source creates competition capable of reducing the likelihood that some newly created infrastructure software will become established in a ‘virgin’ ecosystem.

Open source not only reduces startup costs for those needing infrastructure for a new ecosystem, it also reduces ongoing maintenance costs (by spreading them over multiple ecosystems), and developer costs (by reducing the need to learn something different, which happened to be created by developers who built from scratch).

Some people will complain that Open source is reducing diversity (where diversity is viewed as unconditionally providing benefits). I would claim that reducing diversity in this case is a benefit. Inventing new ways of doing things based on the whims of those doing the invention is a vanity project. I have nothing against people investing their own resources on their own vanity projects, but let’s not pretend that the diversity generated by such projects is likely to provide benefits to others.

By providing the components needed to plug together a functioning infrastructure, Open source reduces the cost of ecosystem ‘invasion’ by software. The resources which might have been invested building infrastructure components can be directed to building higher level functionality.

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A Day At The Races – baron m.

baron m. from thus spake a.k.

Halloo Sir R-----! Pray come join me and partake of a glass of this rather excellent potation!

Might I again tempt you with a wager?

Splendid!

I have in mind a game that always reminds me of my victory upon the turf at Newmarket. Ordinarily I would not participate in a public sporting event such as this since I am at heart a modest man and derive no pleasure in demonstrating my substantial superiority over my fellows.
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New game: Tron – frantic multiplayer retro action

Andy Balaam from Andy Balaam's Blog

My newest game is out now on Smolpxl Games – Tron:

Pixellated lines fight each other to stay alive

Play at smolpxl.gitlab.io/tron.

It’s a frantic multiplayer retro pixellated thingy playable in your browser. Try to stay alive longer than everyone else!

This version allows many players (up to 16 if you can manage it), and is quite pure in its implementation.

There are bots to play against, and you can gather your friends around a keyboard to play together.

Part of the motivation for writing this game was to test my new smolpxl-remote remote-play system, but this is not enabled yet, so watch this space…

I love playing games with other people – preferably at least 3 other people. In theory you could have 8 players around a keyboard playing this – send me a picture if you try!

One feature I worked on in the Smolpxl library for this game: saving configuration to local storage (and asking permission to do so). I ended up with a very ugly hack to do this, so a bit more work is needed before I merge it into the library.

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Running Jest tests in VS Code with custom environment variables

Austin Bingham from Good With Computers

Currently the most popular Jest test runner extension for VS Code is vscode-jest by Orta. For most common setups, this extension works without any configuration needed to VS Code. In my case, though, I needed to enable Jest's support for ECMAScript modules. The Jest documentation lists a few ways to do this, and I decided to use the the method that involves setting an environment variable.

Because I needed to set this environment variable, vscode-jest's default behavior didn't work, and I ended up needing to create a run configuration. This was not particularly complicated, but it was complicated enough that I thought I should capture the knowledge here.

Configuring the Jest command

First you need to configure the Jest command in your settings. To do this you can use the extension's "Setup Extension" command. From the command palette, run "Jest: Setup Extension" (or possibly "Jest: Setup Extension (beta)" if it's still in beta). Choose "Setup Jest Command" in the dropdown this produces.

It will ask if you can run Jest tests from the terminal; choose "yes". When it then asks for the Jest command line, enter "node_modules/.bin/jest". (Of course, if you use something else, enter that!)

This will add an entry like this to your settings.json:

"jest.jestCommandLine": "node_modules/.bin/jest"

Creating the launch configuration

You'll then return to the setup wizard's dropdown list. This time select "Setup Jest Debug Config", and then select "Generate". This will add a run configuration to your launch.json. Now you can select "Exit" from the wizard.

Now that you have the launch configuration, you need to edit it to add the environment variable. Add this to the launch configuration inside launch.json:

"env": {
    "NODE_OPTIONS": "--experimental-vm-modules"
}

You should end up with a configuration that looks something like this:

{
    "configurations": [
        {
            "type": "node",
            "name": "vscode-jest-tests",
            "request": "launch",
            "console": "integratedTerminal",
            "internalConsoleOptions": "neverOpen",
            "disableOptimisticBPs": true,
            "program": "${workspaceFolder}/node_modules/.bin/jest",
            "cwd": "${workspaceFolder}",
            "args": [
                "--runInBand",
                "--watchAll=false"
            ],
            "env": {
                "NODE_OPTIONS": "--experimental-vm-modules"
            }
        }
    ]
}

With this in place, you should be able to run and debug Jest tests from the test tool or directly from the test file.

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Preventing Virgin Media hijacking my DNS

Andy Balaam from Andy Balaam's Blog

Yesterday I learned that Virgin Media is inserting itself into some of my DNS requests. Much as I am not a fan of how powerful Cloudflare are, if they are telling the truth about their DNS, then it’s safe, so I followed their instructions on how to use their DNS and then removed the default DNS and hopefully my Internet will work now.

From the serverfault answer by lauc.exon.nod:

nmcli con mod "Wired connection 1" ipv4.dns "1.1.1.1 1.0.0.1"
nmcli con mod "Wired connection 1" ipv4.ignore-auto-dns yes
nmcli con down "Wired connection 1"
nmcli con up "Wired connection 1"
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A company is not a tree: an alternative map

Allan Kelly from Allan Kelly

It seems that everyone dislikes hierarchy in organizations. Even the people at the top of the hierarchy seem to want to get away from the idea. But… the moment we start talking about organizations everyone starts talking about who’s at the top, the CEO, and who reports to who. Try to draw it out and you end up with some sort of inverted tree.

Part of the problem is that we all want, indeed need, structure. Saying “there is a bunch of people” isn’t enough. We need some way of understanding who is who and where they all fit in. Perhaps we cling to hierarchy because we lack a better model to conceptualise our organizations and who they fit together.

Programmers and business designers aren’t the only ones who want to think of things in a neat tree like hierarchies. I was recently introduced to Christopher Alexander’s essay “A city is not a tree” in which he rails against the same idea. Living in London and I while I could imagine constructing a hierarchy on some criteria I immediately know it would be wrong. It would not capture the true nature of London. Neither Oxford Street or Threadneedle Street are at the top, they would be contenders but in different way. Each part place places multiple roles. There isn’t one centre, there are many centres.

Maps help use make sense of places like London but even here we use different maps with different conventions depending on what we want to do: the Tube map is very different to a visitors map which is different to a map of boroughs, we use different maps for different things. And maps shape our thinking and action – consider the Google map of central London with selective information trying to be useful but also trying to s ell things.

Manager at the centre of the solar system

We need maps of our organizations to understand them but in drawing the map we shape our thinking. If we want to move away from hierarchical thinking we need another way of mapping our organizations.

So let me suggest a different way of thinking about an organization, a way I find useful, a way I briefly mention in my “Reawakening Agile with OKRs” presentation: concentric circles – think of it as our solar system with plants (teams) orbiting the sun (leadership.)

Rather than think of your supreme leader at the top of an organization with everyone else below them – an idea that just shouts “inferior” – think of the supreme leader as the centre of the organization. After all, everyone in the company has a relationship with that person even if relationship with them in the same way that every asteroid in the solar system has a relationship with the sun.

The sun, the leader, exerts a force on everything, everyone, else. Some people are close to the centre and close to the leader – they feel a lot of the leaders force. Others are far away, some are so remote the leader struggles to exert any influence.

And while I say “leader” it might be better to think about the leadership team. Close in there isn’t just one leader, even here leadership is split between a CEO, CFO, and even the board. Nobody has total authority, everyone needs to work with others.

You might also add on the communication paths, some teams communicate with other teams a lot, and some teams hardly at all.

Like the solar system there are alternative centres. Earth has but one Moon, that is influenced by the sun but Earth is a far bigger influence. Jupiter has dozens of moons and exerts a lot more influence on its moons than the sun does. Thats not unlike the way some teams and leaders operate.

These satellites influence each other too – maybe not something astronomers see much but some teams follow similar orbits to others and can influence them. Imagine Mars came close enough to Earth at times to influence the seas the way the moon did – even if they only occurred occasionally it would be meaningful. In a company some teams influence others, one team uses the work of another, or they serve the same customers, or the can disrupt the other.

If we are to navigate our organizations without repeatedly referring to tops and bottoms, ups and down, superiors and inferiors, then we need to start changing the models we use to guide us.

This view might also answer another question I raised a few years ago. In Programmers Rorschach Test I noted that organizational charts look exactly like the structure charts I was taught at University. These were an alternative to flow-charts for structured programming in Pascal like languages.

Think about that: organizational design looks exactly like structured programming: Conway’s Law again.

So what does Object Oriented programming look like? Perhaps the solar system provides an answer: lots of independent objects following their own paths but exerting forces on others.

Add asteroids, comets and dwarf planets to planets and moons and you have plenty of ideas to model with.

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The post A company is not a tree: an alternative map appeared first on Allan Kelly.

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Visual Lint 8.0.6.347 – a Clang download here, a CppCheck download there….

Products, the Universe and Everything from Products, the Universe and Everything

Visual Lint 8.0.6.347 has now been released.

The most notable changes in this build relate to configuration - in particular, the user interface now embeds links to the installers for open source analysis tools, which should make configuring Visual Lint much easier:

Configuration Wizard pageThe user interface now includes download links for selected open source analysis tools

This change was prompted by the fact that the Clang-Tidy installers are quite hard to find on the LLVM Download page, but is also applicable to (for example) CppCheck.

Visual Lint 8.0.6.347 is a recommended maintenance update for Visual Lint 8.0, and includes the following changes:

  • Added direct download links for open source analysis tools such as Clang-Tidy and CppCheck to the Configuration Wizard, Options Dialog and Active Analysis Tool Dialog.

  • When the installation folder of an analysis tool is set in the Configuration Wizard for a particular IDE/project type, the path will now be used as the default for all project types. It can of course still be overridden on a project type by project type (or solution/workspace/project by solution/workspace/project) basis as required.

  • Updated the PC-lint Plus compiler indirect file co-rb-vs2022.lnt to support the public release of Visual Studio 2022 v17.0.0.

  • Updated the Clang-Tidy message database to reflect changes in Clang-Tidy 13.0.0.

  • Corrected the "Status" text in the "Active Analysis Tool" dialog.

Download Visual Lint 8.0.6.347