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Merge pull request #15240 from ClickHouse/fix-random-seed

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Fix strange code
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tavplubix 2020-09-25 01:26:22 +03:00 committed by GitHub
commit 2566478349
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1 changed files with 3 additions and 2 deletions
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5
src/Common/randomSeed.cpp
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@ -4,6 +4,7 @@
#include <Common/Exception.h> #include <Common/Exception.h>
#include <Common/randomSeed.h> #include <Common/randomSeed.h>
#include <Common/SipHash.h> #include <Common/SipHash.h>
#include <common/getThreadId.h>
#include <common/types.h> #include <common/types.h>
@ -19,7 +20,7 @@ namespace DB
DB::UInt64 randomSeed() DB::UInt64 randomSeed()
{ {
struct timespec times; struct timespec times;
if (clock_gettime(CLOCK_THREAD_CPUTIME_ID, &times)) if (clock_gettime(CLOCK_MONOTONIC, &times))
DB::throwFromErrno("Cannot clock_gettime.", DB::ErrorCodes::CANNOT_CLOCK_GETTIME); DB::throwFromErrno("Cannot clock_gettime.", DB::ErrorCodes::CANNOT_CLOCK_GETTIME);
/// Not cryptographically secure as time, pid and stack address can be predictable. /// Not cryptographically secure as time, pid and stack address can be predictable.
@ -27,7 +28,7 @@ DB::UInt64 randomSeed()
SipHash hash; SipHash hash;
hash.update(times.tv_nsec); hash.update(times.tv_nsec);
hash.update(times.tv_sec); hash.update(times.tv_sec);
hash.update(getpid()); hash.update(getThreadId());
hash.update(&times); hash.update(&times);
return hash.get64(); return hash.get64();
} }