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#include <plan9.h>
#include <fcall.h>
#include <u9fs.h>
#include <stdlib.h>
#include <sys/time.h>
#include <fcntl.h>
static long
getseed(void)
{
struct timeval tv;
long seed;
int fd, len;
len = 0;
fd = open("/dev/urandom", O_RDONLY);
if(fd > 0){
len = readn(fd, &seed, sizeof(seed));
close(fd);
}
if(len != sizeof(seed)){
gettimeofday(&tv, nil);
seed = tv.tv_sec ^ tv.tv_usec ^ (getpid()<<8);
}
return seed;
}
static int seeded;
void
randombytes(uchar *r, uint nr)
{
int i;
ulong l;
if(!seeded){
seeded=1;
srand48(getseed());
}
for(i=0; i+4<=nr; i+=4,r+=4){
l = (ulong)mrand48();
r[0] = l;
r[1] = l>>8;
r[2] = l>>16;
r[3] = l>>24;
}
if(i<nr){
l = (ulong)mrand48();
switch(nr-i){
case 3:
r[2] = l>>16;
case 2:
r[1] = l>>8;
case 1:
r[0] = l;
}
}
}
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