conf.h

conf.h is a single-file, public domain (or MIT licensed) library that abstracts the use of Lua config files from C and C++.

A config file for a GUI program:

Config = {
    font = {
        size = 26,
    }
}

Reading the font size:

Conf conf;
Conf_open(&conf, "config.lua");

double val;
Conf_get_num(conf, &val, "Config.font.size");

Conf_close(conf);

conf.h needs Lua 5.1 or LuaJIT (both implement the Lua 5.1 API). Copy conf.h into your project and, in exactly one C/C++ file:

#define INCLUDE_CONF_IMPLEMENTATION
#include "conf.h"

Every other file just does #include "conf.h". The repository's make builds against PUC-Rio Lua 5.1; make LUA=luajit uses LuaJIT.

Both global-table and return-table files work:

-- Global style
Config = { font = { size = 26 } }

-- Return style
return { font = { size = 26 } }

Every Conf_* function returns an int status: CONF_OK (0) on success, non-zero on error. Handle it however fits your style:

assert(Conf_get_num(conf, &val, "Config.font.size") == CONF_OK);

if (Conf_get_num(conf, &val, "Config.font.size") != CONF_OK) {
    // error handling
}

switch (Conf_get_num(conf, &val, "Config.font.size")) {
    case CONF_OK:
    case CONF_INVALID:
    ...
}

Read conf.h for every status code.

• vicel, tffpr and pm read their configuration with it.

• Source code
• conf.h-paper: alternatives, performance and design details.