random.c File Reference

#include "random.h"
#include <stdbool.h>
#include <stdint.h>
#include "debug.h"

Include dependency graph for random.c:

Functions
static void	swap_byte (uint8_t *a, uint8_t *b)
void	random_init (unsigned seed)
void	random_bytes (void *buf_, size_t size)
unsigned long	random_ulong (void)

Variables
static uint8_t	s [256]
static uint8_t	s_i
static uint8_t	s_j
static bool	inited

Function Documentation

random_bytes()

void random_bytes	(	void *	buf_,
		size_t	size
	)

                                       {
    uint8_t *buf;
 
    if (!inited)
        random_init (0);
 
    for (buf = buf_; size-- > 0; buf++) {
        uint8_t s_k;
 
        s_i++;
        s_j += s[s_i];
        swap_byte (s + s_i, s + s_j);
 
        s_k = s[s_i] + s[s_j];
        *buf = s[s_k];
    }
}

Here is the call graph for this function:

Here is the caller graph for this function:

random_init()

void random_init

(

unsigned

seed

)

                            {
    uint8_t *seedp = (uint8_t *) &seed;
    int i;
    uint8_t j;
 
    for (i = 0; i < 256; i++) 
        s[i] = i;
    for (i = j = 0; i < 256; i++) {
        j += s[i] + seedp[i % sizeof seed];
        swap_byte (s + i, s + j);
    }
 
    s_i = s_j = 0;
    inited = true;
}

Here is the call graph for this function:

Here is the caller graph for this function:

random_ulong()

unsigned long random_ulong

(

void

)

                    {
    unsigned long ul;
    random_bytes (&ul, sizeof ul);
    return ul;
}

Here is the call graph for this function:

swap_byte()

static void swap_byte ( uint8_t *  a, uint8_t *  b  )

inlinestatic

                                   {
    uint8_t t = *a;
    *a = *b;
    *b = t;
}

Here is the caller graph for this function:

Variable Documentation

inited

bool inited

static

s

uint8_t s[256]

static

s_i

uint8_t s_i

static

s_j

uint8_t s_j

static