[libgit2.git] / src / util / rand.h

/*
 * Copyright (C) the libgit2 contributors. All rights reserved.
 *
 * This file is part of libgit2, distributed under the GNU GPL v2 with
 * a Linking Exception. For full terms see the included COPYING file.
 */
#ifndef INCLUDE_rand_h__
#define INCLUDE_rand_h__

#include "git2_util.h"

/**
 * Initialize the random number generation subsystem.  This will
 * seed the random number generator with the system's entropy pool,
 * if available, and will fall back to the current time and
 * system information if not.
 */
int git_rand_global_init(void);

/**
 * Seed the pseudo-random number generator.  This is not needed to be
 * called; the PRNG is seeded by `git_rand_global_init`, but it may
 * be useful for testing.  When the same seed is specified, the same
 * sequence of random numbers from `git_rand_next` is emitted.
 *
 * @param seed the seed to use
 */
void git_rand_seed(uint64_t seed);

/**
 * Get the next pseudo-random number in the sequence.
 *
 * @return a 64-bit pseudo-random number
 */
uint64_t git_rand_next(void);

#endif
Commit	Line	Data
e579e0f7 MB	1	/*
	2	* Copyright (C) the libgit2 contributors. All rights reserved.
	3	*
	4	* This file is part of libgit2, distributed under the GNU GPL v2 with
	5	* a Linking Exception. For full terms see the included COPYING file.
	6	*/
	7	#ifndef INCLUDE_rand_h__
	8	#define INCLUDE_rand_h__
	9
ad5611d8	10	#include "git2_util.h"
e579e0f7 MB	11
	12	/**
	13	* Initialize the random number generation subsystem. This will
	14	* seed the random number generator with the system's entropy pool,
	15	* if available, and will fall back to the current time and
	16	* system information if not.
	17	*/
	18	int git_rand_global_init(void);
	19
	20	/**
	21	* Seed the pseudo-random number generator. This is not needed to be
	22	* called; the PRNG is seeded by `git_rand_global_init`, but it may
	23	* be useful for testing. When the same seed is specified, the same
	24	* sequence of random numbers from `git_rand_next` is emitted.
	25	*
	26	* @param seed the seed to use
	27	*/
	28	void git_rand_seed(uint64_t seed);
	29
	30	/**
	31	* Get the next pseudo-random number in the sequence.
	32	*
	33	* @return a 64-bit pseudo-random number
	34	*/
	35	uint64_t git_rand_next(void);
	36
	37	#endif