FastRandomContext Class Reference

Fast randomness source. More...

#include <random.h>

Collaboration diagram for FastRandomContext:

Public Types
typedef uint64_t	result_type

Public Member Functions
	FastRandomContext (bool fDeterministic=false) noexcept
	FastRandomContext (const uint256 &seed) noexcept
	Initialize with explicit seed (only for testing) More...
	FastRandomContext (const FastRandomContext &)=delete
	FastRandomContext (FastRandomContext &&)=delete
FastRandomContext &	operator= (const FastRandomContext &)=delete
FastRandomContext &	operator= (FastRandomContext &&from) noexcept
	Move a FastRandomContext. More...
uint64_t	rand64 () noexcept
	Generate a random 64-bit integer. More...
uint64_t	randbits (int bits) noexcept
	Generate a random (bits)-bit integer. More...
uint64_t	randrange (uint64_t range) noexcept
	Generate a random integer in the range [0..range). More...
std::vector< unsigned char >	randbytes (size_t len)
	Generate random bytes. More...
uint16_t	rand16 ()
	Generate a random 16-bit integer. More...
uint32_t	rand32 () noexcept
	Generate a random 32-bit integer. More...
uint256	rand256 () noexcept
	generate a random uint256. More...
bool	randbool () noexcept
	Generate a random boolean. More...
uint64_t	operator() () noexcept

Static Public Member Functions
static constexpr uint64_t	min ()
static constexpr uint64_t	max ()

Private Member Functions
void	RandomSeed ()
void	FillByteBuffer ()
void	FillBitBuffer ()

Private Attributes
bool	requires_seed {false}
ChaCha20	rng
unsigned char	bytebuf [64]
int	bytebuf_size {0}
uint64_t	bitbuf {0}
int	bitbuf_size {0}

Detailed Description

Fast randomness source.

This is seeded once with secure random data, but is completely deterministic and does not gather more entropy after that.

This class is not thread-safe.

Definition at line 107 of file random.h.

Member Typedef Documentation

result_type

typedef uint64_t FastRandomContext::result_type

Definition at line 200 of file random.h.

Constructor & Destructor Documentation

FastRandomContext() [1/4]

FastRandomContext::FastRandomContext ( bool  fDeterministic = false )

explicitnoexcept

Definition at line 693 of file random.cpp.

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FastRandomContext() [2/4]

FastRandomContext::FastRandomContext ( const uint256 &  seed )

explicitnoexcept

Initialize with explicit seed (only for testing)

Definition at line 642 of file random.cpp.

FastRandomContext() [3/4]

FastRandomContext::FastRandomContext ( const FastRandomContext &  )

delete

FastRandomContext() [4/4]

FastRandomContext::FastRandomContext ( FastRandomContext &&  )

delete

Member Function Documentation

FillBitBuffer()

void FastRandomContext::FillBitBuffer ( )

inlineprivate

Definition at line 129 of file random.h.

FillByteBuffer()

void FastRandomContext::FillByteBuffer ( )

inlineprivate

Definition at line 120 of file random.h.

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max()

static constexpr uint64_t FastRandomContext::max ( )

inlinestaticconstexpr

Definition at line 202 of file random.h.

min()

static constexpr uint64_t FastRandomContext::min ( )

inlinestaticconstexpr

Definition at line 201 of file random.h.

operator()()

uint64_t FastRandomContext::operator() ( )

inlinenoexcept

Definition at line 203 of file random.h.

operator=() [1/2]

FastRandomContext& FastRandomContext::operator= ( const FastRandomContext &  )

delete

operator=() [2/2]

FastRandomContext & FastRandomContext::operator= ( FastRandomContext &&  from )

noexcept

Move a FastRandomContext.

If the original one is used again, it will be reseeded.

Definition at line 702 of file random.cpp.

rand16()

uint16_t FastRandomContext::rand16 ( )

inline

Generate a random 16-bit integer.

Definition at line 188 of file random.h.

rand256()

uint256 FastRandomContext::rand256 ( )

noexcept

generate a random uint256.

Definition at line 621 of file random.cpp.

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rand32()

uint32_t FastRandomContext::rand32 ( )

inlinenoexcept

Generate a random 32-bit integer.

Definition at line 191 of file random.h.

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rand64()

uint64_t FastRandomContext::rand64 ( )

inlinenoexcept

Generate a random 64-bit integer.

Definition at line 150 of file random.h.

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randbits()

uint64_t FastRandomContext::randbits ( int  bits )

inlinenoexcept

Generate a random (bits)-bit integer.

Definition at line 159 of file random.h.

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randbool()

bool FastRandomContext::randbool ( )

inlinenoexcept

Generate a random boolean.

Definition at line 197 of file random.h.

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randbytes()

std::vector< unsigned char > FastRandomContext::randbytes

(

size_t

len

)

Generate random bytes.

Definition at line 632 of file random.cpp.

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RandomSeed()

void FastRandomContext::RandomSeed ( )

private

Definition at line 614 of file random.cpp.

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randrange()

uint64_t FastRandomContext::randrange ( uint64_t  range )

inlinenoexcept

Generate a random integer in the range [0..range).

Definition at line 174 of file random.h.

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Member Data Documentation

bitbuf

uint64_t FastRandomContext::bitbuf {0}

private

Definition at line 115 of file random.h.

bitbuf_size

int FastRandomContext::bitbuf_size {0}

private

Definition at line 116 of file random.h.

bytebuf

unsigned char FastRandomContext::bytebuf[64]

private

Definition at line 112 of file random.h.

bytebuf_size

int FastRandomContext::bytebuf_size {0}

private

Definition at line 113 of file random.h.

requires_seed

bool FastRandomContext::requires_seed {false}

private

Definition at line 109 of file random.h.

rng

ChaCha20 FastRandomContext::rng

private

Definition at line 110 of file random.h.

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The documentation for this class was generated from the following files:

• src/random.h
• src/random.cpp