ccan VS pottery

Hilarious!

But I remember the first time I saw such a program which never freed anything: jitterbug, the simple bug tracker which ran as a CGI script.

It indeed allows a very simple style!

Meanwhile, use ccan/tal (https://github.com/rustyrussell/ccan/blob/master/ccan/tal/_i...) and be happy :)

There's CCAN, maintained by kernel hacker Rusty Russell: http://ccodearchive.net/

Please note that the above link has been claimed by squatters and isn’t the right link for CCAN anymore! The maintainer suggests [1] just using the GitHub repo [2] instead.

[1] https://lists.ozlabs.org/pipermail/ccan/2022-September/00141...

[2] https://github.com/rustyrussell/ccan/

This is a great learning exercise but not very useful because using void* creates practical problems that the compiler cant help you with. IMHO, for a nice vector in C look at https://github.com/rustyrussell/ccan/blob/master/ccan/darray/darray.h

For more advanced intrusive lists in C, I've found that ccan's tlist2 (https://github.com/rustyrussell/ccan/blob/master/ccan/tlist2...) provides a decent model here.

Compared to the linux kernel's intrusive lists, it also tracks the offset of the list_node within the structure contained by the list, which eliminates another class of problems. It does still have the "using the iterator after the for loop is over" issue discussed in this article, but it also already tracks the types as Linus proposed doing in the article to resolve the issue.

ccan library https://github.com/rustyrussell/ccan I think it is used also in the linux kernel(?)

ccan (analagous to cpan, but for C rather than Perl.)

You could use a discriminated union in your list node. You could use a void pointer in your list node, allocate space as needed and memcpy the date into this space, or don't allocate and store pointers to the original data. You could use an intrusive list, like this.

The fallacy in the article is that anyone should code these functions. There's plenty of public domain libraries that do this correctly.

https://github.com/rustyrussell/ccan/blob/master/ccan/endian...

Pottery - The page for open hash map reads "Documentation still needs to be written. In the meantime check out the examples."

"Using macros" is a broad description that covers multiple paradigms. There are libraries that use macros in combination with typed pointers and functions that take void* parameters to provide some degree of API genericity and type safety at the same time (e.g. stb_ds and, as you mentioned, my own CC). There are libraries that use macros (or #include directives) to manually instantiate templates (e.g. STC, M*LIB, and Pottery). And then there are libraries that are implemented entirely or almost entirely as macros (e.g. uthash).

The prototype of CC used this mechanism to provide a generic API for types instantiated via templates (so basically like other container libraries, but with an extendible-_Generic-based API laid over the top of the generated types). This approach has some significant advantages over the approach CC now uses, but I got a bit obsessed with eliminating the need to manually instantiate templates.

I think it's common for C programmers to roll their own. I did the same [0].

I went pretty deep into composable C templates to build mine so it's more powerful than most. The containers can handle non-bitwise-movable types with full C++-style lifecycle functions and such, and the sort algorithms can handle dynamic and non-contiguous arrays (they are powerful enough to implement qsort() [1], which is more than I can say for any other C sort templates I've seen.) My reasoning for the complexity at the time was that any powerful container library is going to be reasonably complex in implementation (as anyone who's looked at STL source code knows), so it just needs to be encapsulated behind a good interface.

I'm not so sure that's true anymore. These sorts of simpler libraries like the one linked here definitely seem to be more popular among C programmers. I think if people are using C, it's not just the C++ language complexity they want to get away from, but also the implementation complexity of libraries and such. There's a balance to be had for sure, and I think the balance varies from person to person, which is why no library has emerged as the de facto standard for containers in C.

[0]: https://github.com/ludocode/pottery

Yes! The include style of templates in C is way better than the old way of huge macros to instantiate code. The template code can look mostly like idiomatic C, it interacts way better with a debugger, it gives better compiler errors... everything about it is better and it's finally starting to become more popular.

I've open sourced my own C template library here:

https://github.com/ludocode/pottery

Not only does it use the #include style of templates, but it actually makes the templates composable. It takes this idea pretty far, for example having a lifecycle template that lets you define operations on your type like move, copy, destroy, etc. This way the containers can fully manage the lifecycles of your types even if they're not bitwise movable.

There's also this other more popular C template library, one that tries to more directly port C++ templates to C but with a lot less features:

https://github.com/glouw/ctl/

This article doesn't really make it clear but the merge sort discussion is specifically about glibc's implementation of qsort(). glibc's qsort() and Wine's qsort() are the only ones I know of that use merge sort to implement qsort(). Most implementations use quick sort.

I recently did my own benchmarking on various qsort()s since I was trying to implement a faster one. The various BSDs and macOS qsort() are all faster than glibc at sorting integers and they don't allocate memory:

https://github.com/ludocode/pottery/tree/master/examples/pot...

Of course sorting is much faster if you can inline the comparator so a templated sort algorithm is always going to be faster than a function that takes a function pointer. But this does not require C++; it can be done in plain C. The templated intro_sort from Pottery (linked above) is competitive with std::sort, as are the excellent swensort/sort templates:

https://github.com/swenson/sort