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Reindent server/core/random_jkiss.c

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This commit is contained in:
Johan Wikman
2015-11-30 16:04:18 +02:00
parent 72dd159f98
commit 233f50f3e6
2 changed files with 66 additions and 27 deletions
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65
server/core/random_jkiss.c
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@ -18,15 +18,15 @@
/**
* @file random_jkiss.c - Random number generator for the MariaDB Corporation MaxScale
*
*
* See http://www0.cs.ucl.ac.uk/staff/d.jones/GoodPracticeRNG.pdf for discussion of random
* number generators (RNGs).
*
* @verbatim
* Revision History
*
* Date Who Description
* 26/08/15 Martin Brampton Initial implementation
* Date Who Description
* 26/08/15 Martin Brampton Initial implementation
*
* @endverbatim
*/
@ -53,18 +53,18 @@ static unsigned int random_jkiss_devrand(void);
static void random_init_jkiss(void);
/***
*
*
* Return a pseudo-random number that satisfies major tests for random sequences
*
*
* @return uint Random number
*
*
*/
unsigned int
unsigned int
random_jkiss(void)
{
unsigned long long t;
unsigned int result;
spinlock_acquire(&random_jkiss_spinlock);
if (!init)
{
@ -88,18 +88,23 @@ random_jkiss(void)
/* Own code adapted from http://www0.cs.ucl.ac.uk/staff/d.jones/GoodPracticeRNG.pdf */
/***
*
*
* Obtain a seed random number from /dev/urandom if available.
*
*
* @return uint Random number
*
*
*/
static unsigned int
static unsigned int
random_jkiss_devrand(void)
{
int fn;
unsigned int r;
if ((fn = open("/dev/urandom", O_RDONLY)) == -1) return 0;
if ((fn = open("/dev/urandom", O_RDONLY)) == -1)
{
return 0;
}
if (read(fn, &r, sizeof(r)) != sizeof(r))
{
r = 0;
@ -109,23 +114,41 @@ random_jkiss_devrand(void)
}
/***
*
*
* Initialise the generator using /dev/urandom if available, and warm up
* with 1000 iterations
*
*
*/
static void
random_init_jkiss(void)
{
int newrand, i;
spinlock_acquire(&random_jkiss_spinlock);
if ((newrand = random_jkiss_devrand()) != 0) x = newrand;
if ((newrand = random_jkiss_devrand()) != 0) y = newrand;
if ((newrand = random_jkiss_devrand()) != 0) z = newrand;
if ((newrand = random_jkiss_devrand()) != 0)
if ((newrand = random_jkiss_devrand()) != 0)
{
x = newrand;
}
if ((newrand = random_jkiss_devrand()) != 0)
{
y = newrand;
}
if ((newrand = random_jkiss_devrand()) != 0)
{
z = newrand;
}
if ((newrand = random_jkiss_devrand()) != 0)
{
c = newrand % 698769068 + 1; /* Should be less than 698769069 */
}
spinlock_release(&random_jkiss_spinlock);
/* "Warm up" our random number generator */
for (i = 0; i < 100; i++) random_jkiss();
for (i = 0; i < 100; i++)
{
random_jkiss();
}
}