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  • Committer: Package Import Robot
  • Author(s): Reinhard Tartler
  • Date: 2012-01-12 22:23:28 UTC
  • mfrom: (0.4.7 sid)
  • mto: This revision was merged to the branch mainline in revision 76.
  • Revision ID: package-import@ubuntu.com-20120112222328-8jqdyodym3p84ygu
Tags: 2:1.0~rc4.dfsg1+svn34540-1
* New upstream snapshot
* upload to unstable

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ffmpeg/libavutil/random_seed.c
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#include <unistd.h>
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#include <fcntl.h>
 
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#include <math.h>
 
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#include <time.h>
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#include "timer.h"
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#include "time.h"
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#include "random_seed.h"
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#include "avutil.h"
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static int read_random(uint32_t *dst, const char *file)
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{
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static uint32_t get_generic_seed(void)
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{
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    clock_t last_t=0;
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    int bits=0;
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    uint64_t random=0;
 
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    clock_t last_t  = 0;
 
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    int bits        = 0;
 
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    uint64_t random = 0;
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    unsigned i;
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    float s=0.000000000001;
 
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    float s = 0.000000000001;
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    for(i=0;bits<64;i++){
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        clock_t t= clock();
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        if(last_t && fabs(t-last_t)>s || t==(clock_t)-1){
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            if(i<10000 && s<(1<<24)){
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                s+=s;
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                i=t=0;
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            }else{
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                random= 2*random + (i&1);
 
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    for (i = 0; bits < 64; i++) {
 
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        clock_t t = clock();
 
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        if (last_t && fabs(t - last_t) > s || t == (clock_t) -1) {
 
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            if (i < 10000 && s < (1 << 24)) {
 
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                s += s;
 
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                i = t = 0;
 
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            } else {
 
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                random = 2 * random + (i & 1);
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                bits++;
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            }
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        }
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        last_t= t;
 
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        last_t = t;
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    }
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#ifdef AV_READ_TIME
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    random ^= AV_READ_TIME();
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    random ^= clock();
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#endif
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    random += random>>32;
 
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    random += random >> 32;
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    return random;
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}