Recent CodeSOD

Code Snippet Of the Day (CodeSOD) features interesting and usually incorrect code snippets taken from actual production code in a commercial and/or open source software projects.

Feb 2021

A Bit of Power

by in CodeSOD on

Powers of two are second nature to a lot of programmers. They're nearly inescapable.

Equally inescapable are programmers finding new ways to do simple things wrong. Take Sander's co-worker, who needed to figure out, given a number of bits, what's the largest possible value you could store in that number of bits. You or I might reach for our language's pow function, but boy, in C++, that might mean you need to add an include file, and that sounds hard, so let's do this instead:

A Lack of Progress

by in CodeSOD on

Progress bars and throbbers are, in theory, tools that let your user know that a process is working. It's important to provide feedback when your program needs to do some long-running task.

Hegel inherited a rather old application, written in early versions of VB.Net. When you kicked off a long running process, it would update the status bar with a little animation, cycling from ".", to "..", to "...".


by in CodeSOD on

Molly's company has a home-grown database framework. It's not just doing big piles of string concatenation, and has a bunch of internal checks to make sure things happen safely, but it still involves a lot of hardcoded SQL strings.

Recently, Molly was reviewing a pull request, and found a Java block which looked like this:

Spacious Backup

by in CodeSOD on

Today's anonymous submitter works on a project which uses Apache Derby to provide database services. Derby is a tiny database you can embed into your Java application, like SQLite. Even though it's part of the application, that doesn't mean it doesn't need to be backed up from time to time.

Our submitter was handed the code because the backup feature was "peculiar", and failed for reasons no one had figured out yet. It didn't take too long to figure out that the failures were triggered by not having enough space on the device for a backup. But they definitely had a enoughFreeSpaceForBackup check, so what was going wrong?

Shorely a Bad Choice

by in CodeSOD on

"This was developed by the offshore team," is usually spoken as a warning. There are a lot of reasons why the code-quality from offshore teams has such a bad reputation. You can list off a bunch of reasons why this is true, but it all boils down to variations on the Princpal-Agent Problem: the people writing the code (the agents) don't have their goals aligned with your company (the principal).

Magnus M recently inherited some C# code which came from the offshore team, and it got principal-agented all over.


by in CodeSOD on

In modern times, there's almost no reason to use Assembly, outside of highly specific and limited cases. For example, I recently worked on a project that uses a PRU, and while you can program that in C, I wanted to be able to count instructions so that I could get extremely precise timings to control LEDs.

In modern times, there's also no reason to use Delphi, but Andre found this code a few years ago, and has been puzzling over it ever since.

Self Improvement in Stages

by in CodeSOD on

Jake has a co-worker named "Eddie". Eddie is the kind of person who is always hoping to change and get better. They're gonna start eating healthier… after the holidays. They're gonna start doing test driven development… on the next project. They'll stop just copying and pasting code… someday.

At least, that's what we can get from this blob of code.

Stocking Up

by in CodeSOD on

Sometimes, you find some code that almost works, that almost makes sense. In a way, that's worse than just plain bad code. René was recently going through some legacy JavaScript code for their warehouse management system.

Like any such warehousing system, there's a problem you have to solve: sometimes, the number of units you need to pick to complete the order is larger than the stock you have available. At that point, you need to make a decision: do you hold the order until stock comes in, do you partially fill it and then follow up with a second shipment, or do you perhaps just cancel the order?

Don't Do This

by in CodeSOD on

Let's say you were writing a type checker in TypeScript. At some point, you would find that you need to iterate across various lists of things, like for example, the list of arguments to a function.

Now, JavaScript (and thus TypeScript) gives you plenty of options for building the right loop for your specific problem. Or, if you look at the code our anonymous submitter sent, you could just choose the wrongest one.

Null and Terminated

by in CodeSOD on

There's plenty of room for debate about what specific poor choices in history lead to the most bugs today. Was it the billion dollar mistake of allowing null pointers? Is it the absolute mess that is C memory management? Or is it C-style strings and all the attendant functions and buffer-overruns they entail?

A developer at Jay's company had been porting some C++ code to a new platform. That developer left, and the wheel-of-you-own-this-now spun and landed on Jay. The code was messy, but mostly functional. Jay was able to get it building, running, and then added a new feature. It was during testing that Jay noticed that some fields in the UI weren't being populated.