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wpi::hashing::detail::hash_state Struct Reference

The intermediate state used during hashing. More...

#include <Hashing.h>

Public Member Functions

void mix (const char *s)
 Mix in a 64-byte buffer of data. More...
 
uint64_t finalize (size_t length)
 Compute the final 64-bit hash code value based on the current state and the length of bytes hashed. More...
 

Static Public Member Functions

static hash_state create (const char *s, uint64_t seed)
 Create a new hash_state structure and initialize it based on the seed and the first 64-byte chunk. More...
 
static void mix_32_bytes (const char *s, uint64_t &a, uint64_t &b)
 Mix 32-bytes from the input sequence into the 16-bytes of 'a' and 'b', including whatever is already in 'a' and 'b'. More...
 

Public Attributes

uint64_t h0
 
uint64_t h1
 
uint64_t h2
 
uint64_t h3
 
uint64_t h4
 
uint64_t h5
 
uint64_t h6
 

Detailed Description

The intermediate state used during hashing.

Currently, the algorithm for computing hash codes is based on CityHash and keeps 56 bytes of arbitrary state.

Member Function Documentation

static hash_state wpi::hashing::detail::hash_state::create ( const char *  s,
uint64_t  seed 
)
inlinestatic

Create a new hash_state structure and initialize it based on the seed and the first 64-byte chunk.

This effectively performs the initial mix.

uint64_t wpi::hashing::detail::hash_state::finalize ( size_t  length)
inline

Compute the final 64-bit hash code value based on the current state and the length of bytes hashed.

void wpi::hashing::detail::hash_state::mix ( const char *  s)
inline

Mix in a 64-byte buffer of data.

We mix all 64 bytes even when the chunk length is smaller, but we record the actual length.

static void wpi::hashing::detail::hash_state::mix_32_bytes ( const char *  s,
uint64_t &  a,
uint64_t &  b 
)
inlinestatic

Mix 32-bytes from the input sequence into the 16-bytes of 'a' and 'b', including whatever is already in 'a' and 'b'.


The documentation for this struct was generated from the following file: