src/util/rand.h

   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
  10 #include "git2_util.h"
  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