AuroraSupport/AuroraRuntime
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[*] Update fallback RNG entropy: reduce expected tick resolution

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This commit is contained in:
Reece Wilson 2023-09-09 13:50:26 +01:00
parent cea3362186
commit cf7be329d6
1 changed files with 8 additions and 2 deletions
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10
Source/RNG/AuRNGEntropy.cpp
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@ -174,7 +174,7 @@ namespace Aurora::RNG
#if 0 #if 0
return clock(); // [...] resolution of 1 posix clock() tick (this is usually 1,000,000 == CLOCKS_PER_SEC per posix, but it can be 1k) return clock(); // [...] resolution of 1 posix clock() tick (this is usually 1,000,000 == CLOCKS_PER_SEC per posix, but it can be 1k)
#else #else
return AuTime::SteadyClockNS() / 1000ull; return AuTime::SteadyClockNS() / 10'000ull;
#endif #endif
} }
@ -197,7 +197,7 @@ namespace Aurora::RNG
do do
{ {
t1 = RngTimeClock(); t1 = RngTimeClock();
while (t1 == RngTimeClock()) // spin within 1 microseconds while (t1 == RngTimeClock()) // spin within 1 microseconds (*)
{ {
a ^= 1; // flip a ^= 1; // flip
} }
@ -207,6 +207,12 @@ namespace Aurora::RNG
{ {
b ^= 1; // flip b ^= 1; // flip
} }
// Update 2023/Sept: Now x10 because we dont have enough timer res on some platforms.
// This is was generally never a CPU limitation or API limitation until Windows XP. Check software or motherboard...
// ...but still, let's continue.
// Deadlocking preprocess init, because for example the motherboard is failing or a VM configuration changed, is pretty dumb.
// (ask me how i know)
} }
while (a == b); // ensure theres enough entropy for a deviation to occur while (a == b); // ensure theres enough entropy for a deviation to occur
acc = (acc << 1) | a; // push the first bit state acc = (acc << 1) | a; // push the first bit state