cryb-to/lib/hash/cryb_fnv.3

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.Dd May 15, 2022
.Dt CRYB_FNV 3
.Os
.Sh NAME
.Nm cryb_fnv0_32_hash ,
.Nm cryb_fnv0_64_hash ,
.Nm cryb_fnv1_32_hash ,
.Nm cryb_fnv1_64_hash ,
.Nm cryb_fnv1a_32_hash ,
.Nm cryb_fnv1a_64_hash
.Nd non-cryptographic hash functions
.Sh LIBRARY
.Lb libcryb-hash
.Sh SYNOPSIS
.In stddef.h
.In stdint.h
.In cryb/hash.h
.Ft uint32_t
.Fn cryb_fnv0_32_hash "const void *data" "size_t len"
.Ft uint64_t
.Fn cryb_fnv0_64_hash "const void *data" "size_t len"
.Ft uint32_t
.Fn cryb_fnv1_32_hash "const void *data" "size_t len"
.Ft uint64_t
.Fn cryb_fnv1_64_hash "const void *data" "size_t len"
.Ft uint32_t
.Fn cryb_fnv1a_32_hash "const void *data" "size_t len"
.Ft uint64_t
.Fn cryb_fnv1a_64_hash "const void *data" "size_t len"
.Sh DESCRIPTION
The
.Fn cryb_fnv0_32_hash ,
.Fn cryb_fnv1_32_hash ,
and
.Fn cryb_fnv1a_32_hash ,
functions return a 32-bit hash of the
.Va len
first bytes of the object pointed to by
.Va data
using the Fowler-Noll-Vo (FNV) 0, 1, and 1a algorithms respectively.
.Pp
The
.Fn cryb_fnv0_64_hash ,
.Fn cryb_fnv1_64_hash ,
and
.Fn cryb_fnv1a_64_hash ,
functions return a 64-bit hash of the
.Va len
first bytes of the object pointed to by
.Va data
using the FNV 0, 1, and 1a algorithms respectively.
.Sh IMPLEMENTATION NOTES
The
.In cryb/hash.h
header provides macros which allows these functions to be referred to
without their
.Dq Li cryb_
prefix.
.Sh SEE ALSO
.Xr cryb_hash 3
.Sh STANDARDS
.Rs
.%A Fowler, Glenn
.%A Noll, Landon Curt
.%A Vo, Kiem-Phong
.%A Eastlake, Donald
.%A Hansen, Tony
.%T The FNV Non-Cryptographic Hash Algorithm
.%D May 29, 2019
.%O draft-eastlake-fnv-17
.%U https://datatracker.ietf.org/doc/html/draft-eastlake-fnv-17
.Re
.Sh AUTHORS
The
.Fn cryb_pearson_hash
and
.Fn cryb_pearson_hash_str
functions and this manual page were written by
.An Dag-Erling Sm\(/orgrav Aq Mt des@des.no .