ffmpeg | branch: master | Michael Niedermayer <michael@niedermayer.cc> | Thu Dec 29 00:34:57 2016 +0100| [7525517593dff427021c893a1b21333510b7803b] | committer: Michael Niedermayer libavutil/random_seed: Ensure that get_generic_seed() spends at least 1/32 sec gathering entropy This may fix the failures on windows Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=7525517593dff42702...
libavutil/random_seed.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/libavutil/random_seed.c b/libavutil/random_seed.c index 0c58c8f..d1c9a3f 100644 --- a/libavutil/random_seed.c +++ b/libavutil/random_seed.c @@ -68,6 +68,7 @@ static uint32_t get_generic_seed(void) 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]; @@ -93,10 +94,13 @@ static uint32_t get_generic_seed(void) } else { last_td = t - last_t; buffer[++i & 511] += last_td % 3294638521U; - if (last_i && i - last_i > 4 || i - last_i > 64 || TEST && i - last_i > 8) - break; + 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) {