rngxx/include/rngxx.h

// C api for rngxx
#ifndef _RNGXX_H
#define _RNGXX_H

#ifndef _RNGXX_IMPL
#define _RNGXX_COMMON_MINIMAL
#endif
#include "rngxx/internal/common.h"
#ifndef _RNGXX_IMPL
#undef _RNGXX_COMMON_MINIMAL
#endif

#ifdef __cplusplus
#ifndef _RNGXX_IMPL_ONLY_TYPES
#warning "C++ compilers might not like this header file. Please use the C++ interface for C++ TUs"
#endif
extern "C" {
#endif

// -- C API types -- (C++ compat)
typedef struct Random rng_t;

enum rng_kind {
	RNG_KIND_CRAND,
};

enum rng_next_flag {
	RNG_TYQ_SIGNED   = 0, // Binary with `unsigned`.
	RNG_TYQ_UNSIGNED = 1 << 0,

	RNG_TYQ_CHAOS    = 1 << 1,
}; // 2 bits

typedef int rng_bool_t;

enum rng_next_type {
	RNG_TY_BLOB = 0,

	RNG_TY_BOOL, // Expects type `rng_bool_t`.

	RNG_TY_INT8,
	RNG_TY_INT16,
	RNG_TY_INT32,
	RNG_TY_INT64,

	RNG_TY_F32,
	RNG_TY_F64,
}; // 4 bits

struct rng_next_opt {
	union {
		// Bounded types
		struct {
			const void* restrict pmin;
			const void* restrict pmax;
		} range;
		// Blob types
		size_t len;
	} bound;

	struct {
		enum rng_next_type type : 4;
		enum rng_next_flag mod  : 2;
		uint8_t _unused		: 2;
	} ty; // 8 bits	
};

typedef __typeof( ((struct rng_next_opt*)NULL)->ty ) rng_next_tyq; // Qualified type

// -- // --
#ifndef _RNGXX_IMPL_ONLY_TYPES

// -- C API functions -- (C++ NO compat)
int rng_raw(rng_t* engine, void* restrict output, struct rng_next_opt opt);
void rng_next_bin(rng_t* engine, unsigned char* restrict output, size_t n);

void* rng_next_ty(rng_t* engine, void* restrict output, enum rng_next_type ty, enum rng_next_flag flags);
void* rng_next_tyb(rng_t* engine, void* restrict output, enum rng_next_type ty, enum rng_next_flag flags, const void* pmin, const void* pmax);

rng_t* rng_new(enum rng_kind kind, const u64 seed[static restrict 1]);
void rng_free(rng_t* rng);

// -- // --
#endif
#ifdef __cplusplus
}
#endif

#endif /* _RNGXX_H */