naka/include/version.h

#ifndef _VERSION_H
#define _VERSION_H

#include "macros.h"
#include "ints.h"

typedef union {
	uint32_t raw;
	// XXX: Punning through this union is unsafe, it may work (on little endian machines), but it is not intended to be punned. Use `v_rawtoc` and `v_ctoraw` instead.
	struct v_comp {
		u8 revision, bugfix, minor, major;
	} comp;
} version_t;

// Convert a native `u32` representation of a version (the output of `VERSION()` macro) to a `version_t`.
#define v_rawtoc_unsafe(raw) ((version_t){ .raw = (raw) })
_mixin version_t v_rawtoc(uint32_t raw)
{
	register version_t out = {
		.comp = {
			.major = VERSION_MAJ(raw),
			.minor = VERSION_MIN(raw),
			.bugfix = VERSION_BF(raw),
			.revision = VERSION_REV(raw),
		},
	};
	return out;
}

/// Convert a `version_t` to its native `u32` representation.
#define v_ctoraw_unsafe(ver) ((ver).raw)
_mixin uint32_t v_ctoraw(version_t ver)
{
	return VERSION(ver.comp.major,
			ver.comp.minor,
			ver.comp.bugfix,
			ver.comp.revision);
}

#define VERSION_C(ma,mi,bf,re) v_rawtoc(VERSION((ma),(mi),(bf),(re)))

#define VERSION_STRING_MAX AS(3 + 3 + 3 + 3 + 3, usize) // maj + min + bf + rev + (..r)

/// Print a version to a string buffer `out`. Return the number of bytes written.
///
/// Has the same semantics as `snprintf`, however, the compiler assumes `str` to be non-NULL. To get the buffer size required, use `v_ctosn_sz()` instead.
usize v_ctosn(version_t ver, usize max, char str[static pOUT max]);

/// Get the buffer size required for `v_ctosn().`
///
/// Same as calling `v_ctosn(ver, 0, NULL)` but won't warn about non-NULL parameter `str`.
usize v_ctosn_sz(version_t ver);

/// Print a version to  a static string buffer. The string buffer is thread local. The next call to this function on the same thread will overwrite the returned buffer.
const char* v_ctoss(version_t ver);

/// Print a version to a `malloc()`d string buffer. The buffer is unique and owned by the callee. The buffer must be `free()`d.
char* v_ctos(version_t ver);

#endif /* _VERSION_H */