X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavutil%2Frandom_seed.c;h=d1c9a3f7046d7efada2e11194819e113ab0f6bb7;hb=65d7d46f717c1d5731a172772c0f16a4b272ab32;hp=d1ded7b50960c6ede82b65b291be0c790b979556;hpb=6fb07c7d85c0d0464e5bdaaad55cc2b774468b3d;p=ffmpeg

diff --git a/libavutil/random_seed.c b/libavutil/random_seed.c
index d1ded7b5096..d1c9a3f7046 100644
--- a/libavutil/random_seed.c
+++ b/libavutil/random_seed.c
@@ -64,9 +64,11 @@ static int read_random(uint32_t *dst, const char *file)
 
 static uint32_t get_generic_seed(void)
 {
-    uint8_t tmp[120];
+    uint64_t tmp[120/8];
     struct AVSHA *sha = (void*)tmp;
     clock_t last_t  = 0;
+    clock_t last_td = 0;
+    clock_t init_t = 0;
     static uint64_t i = 0;
     static uint32_t buffer[512] = { 0 };
     unsigned char digest[20];
@@ -86,15 +88,19 @@ static uint32_t get_generic_seed(void)
 
     for (;;) {
         clock_t t = clock();
-
-        if (last_t == t) {
-            buffer[i & 511]++;
+        if (last_t + 2*last_td + (CLOCKS_PER_SEC > 1000) >= t) {
+            last_td = t - last_t;
+            buffer[i & 511] = 1664525*buffer[i & 511] + 1013904223 + (last_td % 3294638521U);
         } else {
-            buffer[++i & 511] += (t - last_t) % 3294638521U;
-            if (last_i && i - last_i > 4 || i - last_i > 64 || TEST && i - last_i > 8)
-                break;
+            last_td = t - last_t;
+            buffer[++i & 511] += last_td % 3294638521U;
+            if ((t - init_t) >= CLOCKS_PER_SEC>>5)
+                if (last_i && i - last_i > 4 || i - last_i > 64 || TEST && i - last_i > 8)
+                    break;
         }
         last_t = t;
+        if (!init_t)
+            init_t = t;
     }
 
     if(TEST) {