It's been created to simplify development process under C/C++ language and offers commonly used set of features that C developers often re-invent or search libraries for. Apart from helper methods that replace/extend C standard library, this toolkit also consists of modules that are very helpful in specific areas of expertise, such as graph culling algorithms, JSON5 parser, OpenGL-friendly math library as well as OpenGL helper module and many more...

Library is cross-platform and currently works on i386, amd64 and ARM architectures. It has been tested on Windows, UNIX systems, iOS, Emscripten and Android.

Honorable users of this library

  • librg - Pure C99 game networking library for building simple and elegant cross-platform client-server solutions.

Table of Contents

ZPL consists of the following modules:

  • Macro helpers - This module contains many useful macros helpful for debugging as well as development itself.
  • Memory - Consists of pointer arithmetic methods, virtual memory management and custom memory allocators.
  • Threading - This module features common threading and blocking principles. It contains thread merge operation based on stb_sync, as well as CPU affinity management.
  • Sorting - Methods for sorting arrays using either Quick/Merge-sort combo or Radix sort. It also contains simple implementation of binary search, as well as an easy to use API to define your own comparators.
  • String - Offers methods for c-string manipulation, but also a string library based on gb_string, which is c-string friendly.
  • Regex - Port of gb_regex with several bugfixes applied. This is a simple regex library and is fast to perform.
  • Containers - Consists of C++ template-like macros that define containers for any type. All of these containers are C friendly and accessible using de-reference or [] operators. These are: buffer, array, linked-list, ring buffer.
  • Hashing - Several hashing methods used by ZPL internally but possibly useful outside of it. Contains: adler32, crc32/64, fnv32/64/a and murmur32/64
  • Hashtable - An instantiated hashtable implementation which works for any type defined.
  • File - File I/O operations as well as path and folder structure manipulation methods. With threading enabled, it also offers async read/write methods.
  • Print - Re-implementation of printf methods.
  • DLL - Helper methods for loading a dynamic library. It also offers an ability to load a procedure address.
  • Time - Helper methods for retrieving the current time in many forms under different precisions. It also offers a simple to use timer library.
  • Event - Simple event handler which can fire multiple callbacks per registered event.
  • JSON5 parser - Easy to use and very fast JSON5 parser that can easily load 50 megabytes of JSON content under half a second. It also contains simple JSON5 writer and acts as a good library for handling config files.
  • Opts - Opts is a CLI options parser, it can parse flags, switches and arguments from command line and offers an easy way to express input errors as well as the ability to display help screen.
  • Process - Gives you the ability to create a new process, wait for it to end or terminate it. It also exposes standard I/O with configurable options.
  • Thread pool - Can set up a batch of workers which use thread-pool pattern to handle async tasks without the unecessary threading overhead.
  • Co-routines - This module implements co-routines feature for C99.
  • Math - OpenGL gamedev friendly library for math.
  • Platform layer - A port of gb_platform which gains access to window and input management, as well as graphics. (Works only on Windows so far).
  • OpenGL - Offers OpenGL helper methods as well as basic 2D sprite and font rendering.
  • Miscellaneous - Methods that don't belong anywhere but are still very useful in many occasions.

External modules

These are modules that work either as a standalone library or didn't fit into the ZPL library itself:

  • - A Python script which fetches glcorearb.h to generate zpl_glgen.h which acts as an OpenGL extension wrangler.
  • zpl_image.h - Image manipulation methods and simple GIF reading API.

This repository also contains third-party libraries which were either included or modified to be used by some of these ZPL external modules.


Documentation is available in its generated form at

You can see all modules by accessing the Modules link.

Note that the documentation is still work in progress and will be tweaked further.

You can build the documentation using Doxygen 1.8.11 or later. We use modified version of m.css to generate styled documentation. It uses Python3 with dependencies: jinja2, Pygments to generate files. You can use docs.bat to build offline documentation.

m.css is available as submodule, so make sure you clone this repo recursively to obtain it.

Example Usage

In this example, I'll show you how to write a simple JSON5 benchmark tool by using ZPL only.

First, I recommend looking at zpl.h header file, which describes how to use the library. Now you know, that to use zpl.h in your project, you have to define ZPL_IMPLEMENTATION exactly in ONE SOURCE file BEFORE including the zpl.h file itself to successfully embed it.

Afterwards, we need to deal with file loading, this time, we can either search for file module inside of zpl.h (not recommended), or we can navigate to code/zpl/ to see the original form of the ZPL library.

As you can see, each module is contained within its own source file. There's also a Python script called which generates a new zpl.h file, combining all these modules together.

Here we need _file.c, which contains necessary file i/o operations. Write a code to read test.json5 file (you can use zpl_file_read_contents) and try to print its content (either use libc's printf or methods from _print.c) Check test folder for code examples.

Done? Great! Now we need to parse this file, but how? Well guess what, _json.c is exactly what you're looking for! Now you might wonder, you can parse JSON5 files...

But what use is it for a benchmark tool if it doesn't even let you know how long the process took? It is time (pun intended) to visit _time.c file now, capture 2 timestamps, one before, another after the operation and the difference is your time you can display to user. Or just check out code examples in test folder.

What's left? We can read a specific JSON5 file, parse it and display the time it took to do so. Did I say.. specific? How about we let the user customise the options on the command line?

Visit _opts.c and get to know it. As always, test folder can be useful in this case.

Actually, the following snippet comes from the json_benchmark.c test file:

#include <zpl.h>

int main(int argc, char **argv) {
    zpl_opts opts={0};

    zpl_opts_init(&opts, zpl_heap(), argv[0]);

    zpl_opts_add(&opts, "f", "file", "input file name.", ZPL_OPTS_STRING);
    zpl_opts_add(&opts, "s", "strip-comments", "strip comments from JSON file (recommended).", ZPL_OPTS_FLAG);

    zpl_opts_positional_add(&opts, "file");

    b32 ok = zpl_opts_compile(&opts, argc, argv);

    char *filename = NULL;
    b32 strip_comments = false;

    if (ok && zpl_opts_positionals_filled(&opts))
        filename = zpl_opts_string(&opts, "file", NULL);
        strip_comments = zpl_opts_has_arg(&opts, "strip-comments");

        if (filename == NULL)
            goto bad;

        printf("Filename: %s\n", filename);
        return -1;

    zpl_file_contents fc = zpl_file_read_contents(zpl_heap(), true, filename);

    printf("Parsing JSON5 file!\n");

    zpl_json_object root = {0};

    u8 err;
    f64 time = zpl_time_now();
    zpl_json_parse(&root, fc.size, (char *), zpl_heap(), strip_comments, &err);
    f64 delta = zpl_time_now() - time;

        printf("File not found!\n");
        return -2;

    printf("Delta: %fms\nNo. of nodes: %lld\nError code: %d\nFile size: %lldbytes\n", delta*1000, 
            zpl_array_count(root.nodes), err, fc.size);

    return 0;

Have fun!

Frequently Asked Questions

What led you to the creation of this library?

I personally found it rather cumbersome to re-implement commonly used features in C language. I used to use others' libraries to rely on those features. However, I once started extending those libraries by my own modules, breaking the style the original libraries were made. Thanks to FOSS, I've decided to fork @gingerBill's library and adjusted it to my personal style and needs, while also returning bugfixes and some features back. ZPL later became independent and its own thing, adding new features, code structure and QoL changes.

Can I contribute to the project?

Yes, indeed. This project is dual-licensed according to LICENSE, you are free to fork it, contribute to it or even sell it as you see fit.

Why C99?

Why not?

Can I submit suggestions?

Indeed, I'd also gladly discuss those with you on Discord, if possible.