#include <unistd.h>
#include <fcntl.h>
#include "timer.h"
+#include "time.h"
#include "random_seed.h"
#include "avutil.h"
if (fd == -1)
return -1;
- err = read(fd, dst, sizeof(*dst));
+ err = read(fd, dst, sizeof(*dst));
close(fd);
return err;
}
+static uint32_t get_generic_seed(void)
+{
+ clock_t last_t=0;
+ int bits=0;
+ uint64_t random=0;
+ unsigned i;
+ float s=0.000000000001;
+
+ for(i=0;bits<64;i++){
+ clock_t t= clock();
+ if(last_t && fabs(t-last_t)>s || t==(clock_t)-1){
+ if(i<10000 && s<(1<<24)){
+ s+=s;
+ i=t=0;
+ }else{
+ random= 2*random + (i&1);
+ bits++;
+ }
+ }
+ last_t= t;
+ }
+#ifdef AV_READ_TIME
+ random ^= AV_READ_TIME();
+#else
+ random ^= clock();
+#endif
+
+ random += random>>32;
+
+ return random;
+}
+
uint32_t av_get_random_seed(void)
{
uint32_t seed;
- int err;
- err = read_random(&seed, "/dev/urandom");
- if (err != sizeof(seed))
- err = read_random(&seed, "/dev/random");
- if (err == sizeof(seed))
+ if (read_random(&seed, "/dev/urandom") == sizeof(seed))
return seed;
-
-#ifdef AV_READ_TIME
- seed = AV_READ_TIME();
-#endif
- // XXX what to do ?
- return seed;
+ if (read_random(&seed, "/dev/random") == sizeof(seed))
+ return seed;
+ return get_generic_seed();
}
#if LIBAVUTIL_VERSION_MAJOR < 51