Internet-Draft FNV October 2024
Fowler, et al. Expires 13 April 2025 [Page]
Workgroup:
Internet Engineering Task Force
Internet-Draft:
draft-eastlake-fnv-29
Published:
Intended Status:
Informational
Expires:
Authors:
G. Fowler
Google
L. Noll
Cisco Systems
K. Vo
Google
D. Eastlake
Independent
T. Hansen
AT&T

The FNV Non-Cryptographic Hash Algorithm

Abstract

FNV (Fowler/Noll/Vo) is a fast, non-cryptographic hash algorithm with good dispersion that is referenced in a number of standards documents and widely used. The purpose of this document is to make information on FNV and open source code performing all specified sizes of FNV conveniently available to the Internet community.

Status of This Memo

This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79.

Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet-Drafts is at https://datatracker.ietf.org/drafts/current/.

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This Internet-Draft will expire on 13 April 2025.

▲

Table of Contents

1. Introduction

FNV hashes are designed to be fast while maintaining a low collision rate. Their exceptional dispersion makes them particularly well-suited for hashing nearly identical strings, including URLs, hostnames, filenames, text, and IP addresses. Their speed allows one to quickly hash lots of data while maintaining a reasonably low collision rate.

FNV hashes are generally not suitable for cryptographic use. That is to say, they are generally not applicable for use when faced with an active adversary in a security scheme where the modest effort required to compute FNV hashes (see Appendix A) and their other noncryptographic characteristics (see Section 7.1) would make the scheme ineffective against the threat model being considered.

FNV hash algorithms and source code have been released into the public domain. The authors took deliberate steps to disclose the algorithm in a public forum soon after it's invention. More than a year passed after this public disclosure and the authors deliberately took no steps to patent the FNV algorithm. Therefore, it is safe to say that the FNV authors have no patent claims on the FNV algorithm.

1.1. FNV Hash Uses

The FNV hash is widely used. For example it is referenced in the [RFC7357], [RFC7873], and [IEEE8021Qbp] standards documents. It is also used in DNS servers, the X (formerly Twitter) service, database indexing hashes, major web search / indexing engines, netnews history file Message-ID lookup functions, anti-spam filters, a spellchecker programmed in Ada 95, flatassembler's open source x86 assembler - user-defined symbol hashtree, non-cryptographic file fingerprints, computing Unique IDs in DASM (DTN (Delay Tolerant Networking) Applications for Symbian Mobile-phones), Microsoft's hash_map implementation for VC++ 2005, the realpath cache in PHP 5.x (php-5.2.3/TSRM/tsrm_virtual_cwd.c), and many other uses.

A study has recommended FNV in connection with the IPv6 Flow Label field [IPv6flow]. Additionally, there was a proposal to use FNV for BFD sequence number generation [BFDseq].

If you use an FNV function in an application, you are kindly requested to send an EMail about it to: [email protected]

1.2. FNV Hash Origin

The FNV hash algorithm originated from an idea submitted as reviewer comments to the [IEEE] POSIX P1003.2 committee in 1991 by Glenn Fowler and Phong Vo. Subsequently, during a ballot round, Landon Curt Noll proposed an enhancement to their algorithm. Some people tried this hash and found that it worked rather well. In an EMail message to Landon, they named it the "Fowler/Noll/Vo" or FNV hash. [FNV]

2. FNV Basics

This document focuses on the FNV-1a function whose pseudo-code is as follows:

  hash = offset_basis
  for each octet_of_data to be hashed
      hash = hash xor octet_of_data
      hash = hash * FNV_Prime
  return hash

In the pseudo-code above, hash is a power-of-two number of bits (32, 64, 128, 256, 512, or 1024) and offset_basis and FNV_Prime depend on the size of hash.

The FNV-1 algorithm is the same, including the values of offset_basis and FNV_Prime, except that the order of the two lines with the "xor" and multiply operations are reversed. Operational experience indicates better hash dispersion for small amounts of data with FNV-1a. FNV-0 is the same as FNV-1 but with offset_basis set to zero. FNV-1a is suggested for general use.

2.1. FNV Primes

The theory behind FNV_Prime's is beyond the scope of this document but the basic property to look for is how an FNV_Prime would impact dispersion. Now, consider any n-bit FNV hash where n >= 32 and is also a power of 2, in particular n = 2**s. For each such n-bit FNV hash, an FNV_Prime p is defined as:

Experimentally, FNV_Primes matching the above constraints tend to have better dispersion properties. They improve the polynomial feedback characteristic when an FNV_Prime multiplies an intermediate hash value. As such, the hash values produced are more scattered throughout the n-bit hash space.

The case where s < 5 is not considered due to the resulting low hash quality. Such small hashes can, if desired, be derived from a 32 bit FNV hash by XOR folding (see Section 3). The case where s > 10 is not considered because of the doubtful utility of such large FNV hashes and because the criteria for such large FNV_Primes is more complex, due to the sparsity of such large primes, and would needlessly clutter the criteria given above.

Per the above constraints, an FNV_Prime should have only 6 or 7 one-bits in it: one relatively high order one bit, the 2**9 bit, and 4 or 5 one bits in the low order byte. Therefore, some compilers may seek to improve the performance of a multiplication with an FNV_Prime by replacing the multiplication with shifts and adds. However, note that the performance of this substitution is highly hardware-dependent and should be done with care. The selection of FNV_Primes prioritizes the quality of the resulting hash function, not compiler optimization considerations.

2.2. FNV offset_basis

The offset_basis values for the n-bit FNV-1a algorithms are computed by applying the n-bit FNV-0 algorithm to the 32 octets representing the following character string in ASCII [RFC0020]:

chongo <Landon Curt Noll> /\../\

The \'s in the above string are not C-style escape characters. In C-string notation, these 32 octets are:

"chongo <Landon Curt Noll> /\\../\\"

That string was used because the person testing FNV with non-zero offset_basis values was looking at an email message from Landon and was copying his standard email signature line; however, they couldn't see very well and copied it incorrectly. In fact, he uses

chongo (Landon Curt Noll) /\oo/\

but, since it doesn't matter, no effort has been made to correct this.

In the general case, almost any offset_basis will serve so long as it is non-zero. The choice of a non-standard offset_basis may be beneficial in defending against some attacks that try to induce hash collisions as discussed in Section 7.2.

2.3. FNV Endianism

For persistent storage or interoperability between different hardware platforms, an FNV hash shall be represented in the little endian format. That is, the FNV hash will be stored in an array hash[N] with N bytes such that its integer value can be retrieved as follows:

  unsigned char   hash[N];
  for ( i = N-1, value = 0; i >= 0; --i )
      value = ( value << 8 ) + hash[i];

Of course, when FNV hashes are used in a single process or a group of processes sharing memory on processors with compatible endian-ness, the natural endian-ness of those processors can be used, as long as it is used consistently, regardless of its type, little, big, or some other exotic form.

The code provided in Section 6 has FNV hash functions that return a little endian byte vector for all lengths. Because they are more efficient, the code also provides for return of FNV hashes as 32-bit integers or, where supported, 64-bit integers, for those sizes of FNV hash. Such integers are compatible with the same size byte vectors on little endian computers but use of the functions returning integers on big endian or other non-little-endian machines will be byte-reversed or otherwise incompatible with the byte vector return values.

3. Other Hash Sizes and XOR Folding

Many hash uses require a hash that is not one of the FNV sizes for which constants are provided in Section 5. If a larger hash size is needed, please contact the authors of this document.

For scenarios where a fixed-size binary field of k bits is desired with k < 1024 but not among the provided constants in Section 5, the recommended approach involves using the smallest FNV hash of size S where S > k and employing xor folding, as shown below. The final bit masking operation is logically unnecessary if the size of the variable k-bit-hash is exactly k bits.

  temp = FNV_S ( data-to-be-hashed )
  k-bit-hash = ( temp xor temp>>k ) bitwise-and ( 2**k - 1 )

Hash functions are a trade-off between speed and strength. For example, a somewhat stronger hash may be obtained for exact FNV sizes by calculating an FNV twice as long as the desired output ( S = 2*k ) and performing such data folding using a k equal to the size of the desired output. However, if a much stronger hash, for example one suitable for cryptographic applications, is wanted, algorithms designed for that purpose, such as those in [RFC6234], should be used.

If it is desired to obtain a hash result that is a value between 0 and max, where max+1 is a not a power of two, simply choose an FNV hash size S such that 2**S > max. Then calculate the following:

FNV_S mod ( max+1 )

The resulting remainder will be in the range desired but will suffer from a bias against large values with the bias being larger if 2**S is only a little bigger than max. If this bias is acceptable, no further processing is needed. If this bias is unacceptable, it can be avoided by retrying for certain high values of hash, as follows, before applying the mod operation above:

  X = ( int( ( 2**S - 1 ) / ( max+1 ) ) ) * ( max+1 )
  while ( hash >= X )
      hash = ( hash * FNV_Prime ) + offset_basis

4. Hashing Multiple Values Together

It is common for there to be a few different component values, say three strings X, Y, and Z, where a hash over all of them is desired. The simplest thing to do is to concatenate them in a fixed order and compute the hash of that concatenation, as in

hash ( X | Y | Z )

where the vertical bar character ("|") represents string concatenation. If the components being combined are of variable length, some information is lost by simple concatenation. For example, X = "12" and Y = "345" would not be distinguished from X = "123" and Y = "45". To preserve that information, each component should be preceded by an encoding of its length or some similar technique used.

Note that, for FNV, the same hash results if X, Y, and Z are actually concatenated and the FNV hash applied to the resulting string or if FNV is calculated on an initial substring and the result used as the offset_basis when calculating the FNV hash of the remainder of the string. This can be done several times. Assuming FNVoffset_basis ( v, w ) is FNV of w using v as the offset_basis, then in the example above, fnvx = FNV ( X ) could be calculated and then fnvxy = FNVoffset_basis ( fnvx, Y ), and finally fnvxyz = FNVoffset_basis ( fnvxy, Z). The resulting fnvxyz would be the same as FNV ( X | Y | Z ).

Cases are also common where such a hash needs to be repeatedly calculated where the component values vary but some vary more frequently than others. For example, assume some sort of computer network traffic flow ID, such as the IPv6 flow ID [RFC6437], is to be calculated for network packets based on the source and destination IPv6 address and the Traffic Class [RFC8200]. If the Flow ID is calculated in the originating host, the source IPv6 address would likely always be the same or perhaps assume one of a very small number of values. By placing this quasi-constant IPv6 source address first in the string being FNV hashed, FNV ( IPv6source ) could be calculated and used as the offset_basis for calculating FNV of the IPv6 destination address and Traffic Class for each packet. As a result, the per packet hash would be over 17 bytes rather than over 33 bytes saving computational resources. The source code in this document includes functions facilitating the use of a non-standard offset_basis.

5. FNV Constants

The FNV Primes are as follows:

Table 1
Size FNV Prime = Expression
= Decimal
= Hexadecimal
32-bit FNV_Prime = 2**24 + 2**8 + 0x93
= 16,​777,​619
= 0x01000193
64-bit FNV_Prime = 2**40 + 2**8 + 0xB3
= 1,​099,​511,​628,​211
= 0x00000100 000001B3
128-bit FNV_Prime = 2**88 + 2**8 + 0x3B
= 309,​485,​009,​821,​345,​068,​724,​781,​371
= 0x00000000 01000000 00000000 0000013B
256-bit FNV_Prime = 2**168 + 2**8 + 0x63
= 374,​144,​419,​156,​711,​147,​060,​143,​317,​175,​368,​453,​031,​918,​731,​002,​211
= 0x0000000000000000 0000010000000000 0000000000000000 0000000000000163
512-bit FNV_Prime = 2**344 + 2**8 + 0x57
= 35,​835,​915,​874,​844,​867,​368,​919,​076,​489,​095,​108,​449,​946,​327,​955,​754,​392,​558,​399,​825,​615,​420,​669,​938,​882,​575,​126,​094,​039,​892,​345,​713,​852,​759
= 0x0000000000000000 0000000000000000 0000000001000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000157
1024-bit FNV_Prime = 2**680 + 2**8 + 0x8D
= 5,​016,​456,​510,​113,​118,​655,​434,​598,​811,​035,​278,​955,​030,​765,​345,​404,​790,​744,​303,​017,​523,​831,​112,​055,​108,​147,​451,​509,​157,​692,​220,​295,​382,​716,​162,​651,​878,​526,​895,​249,​385,​292,​291,​816,​524,​375,​083,​746,​691,​371,​804,​094,​271,​873,​160,​484,​737,​966,​720,​260,​389,​217,​684,​476,​157,​468,​082,​573
= 0x0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000010000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 000000000000018D

The FNV offset_basis values are as follows:

Table 2
Size offset_basis
= Decimal
= Hexadecimal
32-bit offset_basis
= 2,​166,​136,​261
= 0x811C9DC5
64-bit offset_basis
= 14,​695,​981,​039,​346,​656,​037
= 0xCBF29CE4 84222325
128-bit offset_basis
= 144,​066,​263,​297,​769,​815,​596,​495,​629,​667,​062,​367,​629
= 0x6C62272E 07BB0142 62B82175 6295C58D
256-bit offset_basis
= 100,​029,​257,​958,​052,​580,​907,​070,​968,​620,​625,​704,​837,​092,​796,​014,​241,​193,​945,​225,​284,​501,​741,​471,​925,​557
= 0xDD268DBCAAC55036 2D98C384C4E576CC C8B1536847B6BBB3 1023B4C8CAEE0535
512-bit offset_basis
= 9,​659,​303,​129,​496,​669,​498,​009,​435,​400,​716,​310,​466,​090,​418,​745,​672,​637,​896,​108,​374,​329,​434,​462,​657,​994,​582,​932,​197,​716,​438,​449,​813,​051,​892,​206,​539,​805,​784,​495,​328,​239,​340,​083,​876,​191,​928,​701,​583,​869,​517,​785
= 0xB86DB0B1171F4416 DCA1E50F309990AC AC87D059C9000000 0000000000000D21 E948F68A34C192F6 2EA79BC942DBE7CE 182036415F56E34B AC982AAC4AFE9FD9
1024-bit offset_basis
= 14,​197,​795,​064,​947,​621,​068,​722,​070,​641,​403,​218,​320,​880,​622,​795,​441,​933,​960,​878,​474,​914,​617,​582,​723,​252,​296,​732,​303,​717,​722,​150,​864,​096,​521,​202,​355,​549,​365,​628,​174,​669,​108,​571,​814,​760,​471,​015,​076,​148,​029,​755,​969,​804,​077,​320,​157,​692,​458,​563,​003,​215,​304,​957,​150,​157,​403,​644,​460,​363,​550,​505,​412,​711,​285,​966,​361,​610,​267,​868,​082,​893,​823,​963,​790,​439,​336,​411,​086,​884,​584,​107,​735,​010,​676,​915
= 0x0000000000000000 005F7A76758ECC4D 32E56D5A591028B7 4B29FC4223FDADA1 6C3BF34EDA3674DA 9A21D90000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 0000000000000000 000000000004C6D7 EB6E73802734510A 555F256CC005AE55 6BDE8CC9C6A93B21 AFF4B16C71EE90B3

6. The Source Code

The following sub-sections provide reference C source code and a test driver with command line interface for FNV-1a. Alternative source code for 32- and 64-bit FNV-1 and FNV-1a including in x86 assembler, is currently available at [FNV].

Section 6.2 provides the C header and code source files for the FNV functions. Section 6.3 provides the test driver. Section 6.4 provide a simple makefile to build the test driver or a library file with all FNV sizes.

6.1. Source Code Details

6.1.1. FNV Functions Available

The functions provided are listed below. The "xxx" in the function names is "32", "64", "128", "256", "512", or "1024" depending on the length of the FNV. All of the FNV hash functions have as their return value an integer whose meaning is specified in FNVErrorCodes.h.

Functions providing a byte vector hash are available for all lengths. For FNV-32, versions are available that provide a 32-bit integer and are identified by replacing "xxx" with "32INT". For example, FNV32string provides a 4-byte vector but FNV32INTstring provides a 32-bit integer. For FNV-64, if compiled with 64-bit integers enabled (i.e., FNV_64bitIntegers defined, see FNVconfig.h), versions are available that provide a 64-bit integer and are identified by replacing "xxx" with "64INT"`. Versions providing an integer hash will not be compatible between systems of different endian-ness (see Section 2.3).

If you want to copy the source code from this document, note that it is indented by three spaces in the ".txt" version. It may be simplest to copy from the ".html" version of this document.

FNVxxxstring, FNVxxxblock, FNVxxxfile:
FNVxxxINTstring, FNVxxxINTblock, FNVxxxINTfile:
These are simple functions for directly returning the FNV hash of a zero terminated byte string not including that zero byte, the FNV hash of a counted block of bytes, and the FNV of a file, respectively. Note that for applications of FNV-32 and FNV-64 where 64-bit integers are supported and an integer data type output is acceptable, the code is sufficiently simple that, to maximize performance, use of open coding or macros may be more appropriate than calling a subroutine.
FNVxxxinit, FNVxxxinitBasis:
FNVxxxINTinitBasis:
These functions and the next two sets of functions below provide facilities for incrementally calculating FNV hashes. They all assume a data structure of type FNVxxxcontext that holds the current state of the hash. FNVxxxinit initializes that context to the standard offset_basis. FNVxxxinitBasis takes an offset_basis value as a parameter and may be useful for hashing concatenations, as described in Section 4, as well as for simply using a non-standard offset_basis.
FNVxxxblockin, FNVxxxstringin:
These functions hash a sequence of bytes into an FNVxxxcontext that was originally initialized by FNVxxxinit or FNVxxxinitBasis. FNVxxxblockin hashes in a counted block of bytes. FNVxxxstringin hashes in a zero terminated byte string not incuding the final zero byte.
FNVxxxresult:
FNVxxxINTresult:
This function extracts the final FNV hash result from an FNVxxxcontext.

6.1.2. Source Files and 64-bit Support

Code optimized for 64-bit integer support, that is, support of 64-bit integer addition and 32x32-bit multiplication producing a 64-bit product, is provided based on whether or not the FNV_64bitIntegers symbol is defined. By default, this is set in FNVconfig.h based on the compilation target; however, this can be overridden by editing that file or by defining certain symbols in, for example, a command line invoking compilation.

For support of a single FNV size, say "xxx", in an application, the application itself needs to include the FNVxxx.h (which will, in turn, include the FNVconfig.h and FNVErrorCodes.h) files. To build the particular FNVxxx code itself, compile the FNVxxx.c file with FNVconfig.h, fnv-private.h, FNVErrorCodes.h, and FNVxxx.h available. Since the test program in Section 6.3 uses all sizes of FNV, all the .c and .h files are needed to compile it.

6.1.3. Command Line Interface

The test program provided in Section 6.3 has a command line interface. By default, with no command line arguments, it runs tests of all FNV lengths. Command line options are as follows:

FNVhash [-a] [-t nnn] [-u nnn] [-v] [-f filename] [token ...]

The option letters have the following meaning:

-a
Run tests for all lengths.
-v
Complement the Verbose flag which is initially off. When the flag is on, the program prints more information during tests, etc.
-t nnn
Run tests for length nnn which must be one of 32, 63, 128, 256, 512, or 1024.
-u nnn
Use hash size nnn which must be one of 32, 63, 128, 256, 512, or 1024. This is useful to set the hash size for use by the -f option or in hashing tokens on the command line after the options.
-f filename
Hash the contents of the file with name filename. The hash size must have been set by a prior -t or -u option in the command line.
token
Tokens appearing on the command line after the options are hashed with the current hash size which must have been set by a prior -t or -u option in the command line.

For example,

FNVhash -t 128 -h -v -t 64 -v -u 256 -f foobar.txt RabOof 1234

runs tests for FNV128, then prints a command line help message, then turns on Verbose, then runs the tests for FNV64, then turns off Verbose, then sets the hash size to 256, then hashes the contents of file foobar.txt, then hashes the token "RabOof", and finally hashes the token "1234".

6.2. FNV-1a C Code

This section provides the direct FNV-1a function for each of the lengths for which it is specified in this document.

The following code is a private header file used by all the FNV functions further below and which states the terms for use and redistribution of all of this code.

<CODE BEGINS> file "fnv-private.h"

//********************** fnv-private.h ************************//
//**************** See RFC NNNN for details *******************//
/* Copyright (c) 2016, 2023, 2024 IETF Trust and the persons
 * identified as authors of the code.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * *  Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * *  Redistributions in binary form must reproduce the above
 *    copyright notice, this list of conditions and the following
 *    disclaimer in the documentation and/or other materials provided
 *    with the distribution.
 *
 * *  Neither the name of Internet Society, IETF or IETF Trust, nor
 *    the names of specific contributors, may be used to endorse or
 *    promote products derived from this software without specific
 *    prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
 * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef _FNV_PRIVATE_H_
#define _FNV_PRIVATE_H_

/*
 *      Six FNV-1a hashes are defined with these sizes:
 *              FNV32          32 bits, 4 bytes
 *              FNV64          64 bits, 8 bytes
 *              FNV128         128 bits, 16 bytes
 *              FNV256         256 bits, 32 bytes
 *              FNV512         512 bits, 64 bytes
 *              FNV1024        1024 bits, 128 bytes
 */

/* Private stuff used by this implementation of the FNV
 * (Fowler, Noll, Vo) non-cryptographic hash function FNV-1a.
 * External callers don't need to know any of this.  */

enum {  /* State value bases for context->Computed */
    FNVinited = 22,
    FNVcomputed = 76,
    FNVemptied = 220,
    FNVclobber = 122 /* known bad value for testing */
};

/* Deltas to assure distinct state values for different lengths */
enum {
   FNV32state = 1,
   FNV64state = 3,
   FNV128state = 5,
   FNV256state = 7,
   FNV512state = 11,
   FNV1024state = 13
};

#endif /* _FNV_PRIVATE_H_ */

<CODE ENDS>

The following code is a simple header file to define the return value error codes for the FNV routines.

<CODE BEGINS> file "FNVErrorCodes.h"

//*********************** FNVErrorCodes.h *************************//
//***************** See RFC NNNN for details. *********************//
/*
 * Copyright (c) 2016, 2023, 2024 IETF Trust and the persons
 * identified as authors of the code.  All rights reserved.
 * See fnv-private.h for terms of use and redistribution.
 */

#ifndef _FNV_ErrCodes_
#define _FNV_ErrCodes_
//******************************************************************
//  All FNV functions provided return as integer as follows:
//       0 -> success
//      >0 -> error as listed below
//
enum {    /* success and errors */
    fnvSuccess = 0,
    fnvNull,          /* Null pointer parameter */
    fnvStateError,    /* called Input after Result or before Init */
    fnvBadParam       /* passed a bad parameter */
};
#endif /* _FNV_ErrCodes_ */

<CODE ENDS>

The following is a configuration header to set whether 64-bit integers are supported.

<CODE BEGINS> file "FNVconfig.h"


//************************ FNVconfig.h **************************//
//**************** See RFC NNNN for details. ********************//
/* Copyright (c) 2016, 2024 IETF Trust and the persons
 * identified as authors of the code.  All rights reserved.
 *
 * See fnv-private.h for terms of use and redistribution.
 */

#ifndef _FNVconfig_H_
#define _FNVconfig_H_

/*  Description:
 *      This file provides configuration ifdefs for the
 *      FNV-1a non-cryptographic hash algorithms. */

/*      FNV_64bitIntegers - Define this if your system supports
 *          64-bit arithmetic including 32-bit x 32-bit
 *          multiplication producing a 64-bit product. If
 *          undefined, it will be assumed that 32-bit arithmetic
 *          is supported including 16-bit x 16-bit multiplication
 *          producing a 32-bit result.
 */

#include <stdint.h>

/* Check if 64-bit integers are supported in the target */

#if defined(__SIZEOF_LONG_LONG__) && __SIZEOF_LONG_LONG__ >= 8
    #define FNV_64bitIntegers
#elif defined(UINT64_MAX)
    #define FNV_64bitIntegers
#else
    #undef FNV_64bitIntegers
#endif

/*      The following allows overriding the
 *      above configuration setting.
 */

#ifdef FNV_TEST_PROGRAM
# ifdef TEST_FNV_64bitIntegers
#  ifndef FNV_64bitIntegers
#   define FNV_64bitIntegers
#  endif
# else
#  undef FNV_64bitIntegers
# endif
# ifndef FNV_64bitIntegers /* causes an error if uint64_t is used */
#  undef uint64_t
#  define uint64_t no_64_bit_integers
# endif
#endif

#endif /* _FNVconfig_H_ */

<CODE ENDS>

6.2.1. FNV32 Code

The header and C source for 32-bit FNV-1a providing a 32-bit integer or 4-byte vector hash.

<CODE BEGINS> file "FNV32.h"


//*************************** FNV32.h ****************************//
//****************** See RFC NNNN for details ********************//
/* Copyright (c) 2016, 2024 IETF Trust and the persons
 * identified as authors of the code.  All rights reserved.
 * See fnv-private.h for terms of use and redistribution.
 */

#ifndef _FNV32_H_
#define _FNV32_H_

/*
 *  Description:
 *      This file provides headers for the 32-bit version of
 *      the FNV-1a non-cryptographic hash algorithm.
 */

#include "FNVconfig.h"
#include "FNVErrorCodes.h"

#include <stdint.h>
#define FNV32size (32/8)
#define FNV32basis 0x811C9DC5

/* If you do not have the ISO standard stdint.h header file, then
 * you must typedef the following types:
 *
 *    type              meaning
 *  uint32_t         unsigned 32-bit integer
 *  uint8_t          unsigned 8-bit integer (i.e., unsigned char)
 */

/*
 *  This structure holds context information for an FNV32 hash
 */
typedef struct FNV32context_s {
    int Computed;  /* state */
    uint32_t Hash;
} FNV32context;

/*
 * Function Prototypes:
 *
 *    FNV32string: hash a zero-terminated string not including
 *                 the terminating zero
 *    FNV32block: hash a specified length byte vector
 *    FNV32file: hash the contents of a file
 *
 *    FNV32init:  initializes an FNV32 context
 *    FNV32initBasis: initializes an FNV32 context with a
 *                    provided 4-byte vector basis
 *    FNV32blockin:  hash in a specified length byte vector
 *    FNV32stringin: hash in a zero-terminated string not
 *                   including the terminating zero
 *    FNV32result: returns the hash value
 *
 * Hash is returned as a 4-byte vector by the functions above,
 *    and the following return a 32-bit unsigned integer:
 *
 *    FNV32INTstring: hash a zero-terminated string not including
 *                 the terminating zero
 *    FNV32INTblock: hash a specified length byte vector
 *    FNV32INTfile: hash the contents of a file
 *
 *    FNV32INTinitBasis: initializes an FNV32 context with a
 *                     provided 32-bit integer basis
 *    FNV32INTresult: returns the hash value
 */

#ifdef __cplusplus
extern "C" {
#endif

/* FNV32 */
extern int FNV32INTstring ( const char *in,
                            uint32_t * const out );
extern int FNV32string ( const char *in,
                         uint8_t out[FNV32size] );
extern int FNV32INTblock ( const void *vin,
                           long int length,
                           uint32_t * const out );
extern int FNV32block ( const void *vin,
                        long int length,
                        uint8_t out[FNV32size] );
extern int FNV32INTfile ( const char *fname,
                          uint32_t * const out );
extern int FNV32file ( const char *fname,
                       uint8_t out[FNV32size] );
extern int FNV32init ( FNV32context * const );
extern int FNV32INTinitBasis ( FNV32context * const,
                            uint32_t basis );
extern int FNV32initBasis ( FNV32context * const,
                            const uint8_t basis[FNV32size] );
extern int FNV32blockin ( FNV32context * const,
                          const void *vin,
                          long int length );
extern int FNV32stringin ( FNV32context * const,
                           const char *in );
extern int FNV32INTresult ( FNV32context * const,
                            uint32_t * const out );
extern int FNV32result ( FNV32context * const,
                         uint8_t out[FNV32size] );

#ifdef __cplusplus
}
#endif

#endif /* _FNV32_H_ */

<CODE ENDS>
<CODE BEGINS> file "FNV32.c"


//************************** FNV32.c **************************//
//**************** See RFC NNNN for details. ******************//
/* Copyright (c) 2016, 2024 IETF Trust and the persons
 * identified as authors of the code.  All rights reserved.
 * See fnv-private.h for terms of use and redistribution.
 */

/* This code implements the FNV (Fowler, Noll, Vo) non-cryptographic
 * hash function FNV-1a for 32-bit hashes.
 */

#include <stdio.h>

#include "fnv-private.h"
#include "FNV32.h"

/* 32-bit FNV_prime = 2^24 + 2^8 + 0x93 */
#define FNV32prime 0x01000193

/* FNV32 hash a zero-terminated string not including the zero
*****************************************************************/
int FNV32INTstring ( const char *in, uint32_t * const out ) {
    uint32_t    temp;
    uint8_t     ch;

    if ( !in || !out )
        return fnvNull; /* Null input pointer */
    temp = FNV32basis;
    while ( (ch = *in++) )
        temp = FNV32prime * ( temp ^ ch );
    *out = temp;
    return fnvSuccess;
}   /* end FNV32INTstring */

/* FNV32 hash a zero-terminated string not including the zero
*****************************************************************/
int FNV32string ( const char *in, uint8_t out[FNV32size] ) {
    uint32_t    temp;
    uint8_t     ch;
    int         i;

    if ( !in || !out )
        return fnvNull; /* Null input pointer */
    temp = FNV32basis;
    while ( (ch = *in++) )
        temp = FNV32prime * ( temp ^ ch );
    for ( i=0; i<FNV32size; ++i )
        out[i] = ((uint8_t *)&temp)[i];
    return fnvSuccess;
}   /* end FNV32string */

/* FNV32 hash a counted block
 ****************************************************************/
int FNV32INTblock ( const void *vin,
                 long int length,
                 uint32_t * const out ) {
    const uint8_t *in = (const uint8_t*)vin;
    uint32_t    temp;

    if ( !in || !out )
        return fnvNull; /* Null input pointer */
    if ( length < 0 )
        return fnvBadParam;
    for ( temp = FNV32basis; length > 0; length-- )
        temp = FNV32prime * ( temp ^ *in++ );
    *out = temp;
    return fnvSuccess;
}   /* end FNV32INTblock */

/* FNV32 hash a counted block
 ****************************************************************/
int FNV32block ( const void *vin,
                 long int length,
                 uint8_t out[FNV32size] ) {
    const uint8_t *in = (const uint8_t*)vin;
    uint32_t    temp;
    int         i;

    if ( !in || !out )
        return fnvNull; /* Null input pointer */
    if ( length < 0 )
        return fnvBadParam;
    for ( temp = FNV32basis; length > 0; length-- )
        temp = FNV32prime * ( temp ^ *in++ );
    for ( i=0; i<FNV32size; ++i )
        out[i] = ((uint8_t *)&temp)[i];
    return fnvSuccess;
}   /* end FNV32block */


//**************************************************************
//       Set of init, input, and output functions below
//       to incrementally compute FNV32
//**************************************************************

/* initialize context
 ***************************************************************/
int FNV32init ( FNV32context * const ctx ) {
    return FNV32INTinitBasis ( ctx, FNV32basis );
}   /* end FNV32init */

/* initialize context with a provided 32-bit integer basis
 ***************************************************************/
int FNV32INTinitBasis ( FNV32context * const ctx, uint32_t basis ) {
    if ( !ctx )
        return fnvNull;
    ctx->Hash = basis;
    ctx->Computed = FNVinited+FNV32state;
    return fnvSuccess;
}   /* end FNV32INTinitBasis */

/* initialize context with a provided 4-byte vector basis
 ***************************************************************/
int FNV32initBasis ( FNV32context * const ctx,
                    const uint8_t basis[FNV32size] ) {
    int     i;

    if ( !ctx )
        return fnvNull;
    for ( i=0; i<FNV32size; ++i )
        ((uint8_t *)&ctx->Hash)[i] = basis[i];
    ctx->Computed = FNVinited+FNV32state;
    return fnvSuccess;
}   /* end FNV32initBasis */

/* hash in a counted block
 ***************************************************************/
int FNV32blockin ( FNV32context * const ctx,
                   const void *vin,
                   long int length ) {
    const uint8_t *in = (const uint8_t*)vin;
    uint32_t    temp;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV32state:
            ctx->Computed = FNVcomputed+FNV32state;
            break;
        case FNVcomputed+FNV32state:
            break;
        default:
            return fnvStateError;
        }
    if ( length < 0 )
        return fnvBadParam;
    for ( temp = ctx->Hash; length > 0; length-- )
        temp = FNV32prime * ( temp ^ *in++ );
    ctx->Hash = temp;
    return fnvSuccess;
}   /* end FNV32blockin */

/* hash in a zero-terminated string not including the zero
 ***************************************************************/
int FNV32stringin ( FNV32context * const ctx, const char *in ) {
    uint32_t    temp;
    uint8_t     ch;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV32state:
            ctx->Computed = FNVcomputed+FNV32state;
            break;
        case FNVcomputed+FNV32state:
            break;
        default:
            return fnvStateError;
        }
    temp = ctx->Hash;
    while ( (ch = (uint8_t)*in++) )
        temp = FNV32prime * ( temp ^ ch );
    ctx->Hash = temp;
    return fnvSuccess;
}   /* end FNV32stringin */

/* return hash as an integer
 ***************************************************************/
int FNV32INTresult ( FNV32context * const ctx,
                     uint32_t * const out ) {
    if ( !ctx || !out )
        return fnvNull;
    if ( ctx->Computed != FNVcomputed+FNV32state )
        return fnvStateError;
    ctx->Computed = FNVemptied+FNV32state;
    *out = ctx->Hash;
    ctx->Hash = 0;
    return fnvSuccess;
}   /* end FNV32INTresult */

/* return hash as a 4-byte vector
 ***************************************************************/
int FNV32result ( FNV32context * const ctx,
                  uint8_t out[FNV32size] ) {
    int     i;

    if ( !ctx || !out )
        return fnvNull;
    if ( ctx->Computed != FNVcomputed+FNV32state )
        return fnvStateError;
    ctx->Computed = FNVemptied+FNV32state;
    for ( i=0; i<FNV32size; ++i )
        out[i] = ((uint8_t *)&ctx->Hash)[i];
    ctx->Hash = 0;
    return fnvSuccess;
}   /* end FNV32result */

/* hash the contents of a file, return 32-bit integer
 ******************************************************************/
int FNV32INTfile ( const char *fname,
                         uint32_t * const out ) {
    FILE *fp;
    long int i;
    char buf[1024];
    FNV32context e32Context;
    int error;

    if ( !fname || !out )
        return fnvNull;

    if ( ( fp = fopen ( fname, "rb") ) == NULL )
        return fnvBadParam;

    if ( (error = FNV32init (&e32Context)) ) {
        fclose(fp);
        return error;
    }

    if ( (error = FNV32blockin ( &e32Context, "", 0)) ) {
        fclose(fp);
        return error;
    }

    while ( ( i = fread ( buf, 1, sizeof(buf), fp ) ) > 0 ) {
        if ( (error = FNV32blockin ( &e32Context, buf, i)) ) {
            fclose(fp);
            return error;
        }
    }

    error = ferror(fp);
    fclose(fp);
    if (error) {
        return fnvBadParam;
    }

    return FNV32INTresult ( &e32Context, out );
}   /* end FNV32INTfile */

/* hash the contents of a file, return 4 byte vector
 ******************************************************************/
int FNV32file ( const char *fname, uint8_t out[FNV32size] ) {
    uint32_t outINT;
    int i, err;

    if ( !out )
        return fnvNull;
    if ( (err = FNV32INTfile ( fname, &outINT )) )
        return err;
    for ( i=0; i<FNV32size; ++i )
        out[i] = ((uint8_t *)&outINT)[i];
    return fnvSuccess;
}   /* end FNV32file */

<CODE ENDS>

6.2.2. FNV64 Code

The header and C source for 64-bit FNV-1a. Provides an 8-byte vector or, optionally, if 64-bit integers are supported, a 64-bit integer hash.

<CODE BEGINS> file "FNV64.h"


//*************************** FNV64.h ****************************//
//***************** See RFC NNNN for details. ********************//
/* Copyright (c) 2016, 2024 IETF Trust and the persons
 * identified as authors of the code.  All rights reserved.
 * See fnv-private.h for terms of use and redistribution.
 */

#ifndef _FNV64_H_
#define _FNV64_H_

/*
 *  Description:
 *      This file provides headers for the 64-bit version of
 *      the FNV-1a non-cryptographic hash algorithm.
 */

#include "FNVconfig.h"
#include "FNVErrorCodes.h"

#include <stdint.h>
#define FNV64size (64/8)
#ifdef FNV_64bitIntegers
#define FNV64basis 0xCBF29CE484222325
#endif

/* If you do not have the ISO standard stdint.h header file, then
 * you must typedef the following types:
 *
 *    type             meaning
 *  uint64_t        unsigned 64-bit integer (ifdef FNV_64bitIntegers)
 *  uint32_t        unsigned 32-bit integer
 *  uint16_t        unsigned 16-bit integer
 *  uint8_t         unsigned 8-bit integer (i.e., unsigned char)
 */

/*
 *  This structure holds context information for an FNV64 hash
 */
#ifdef FNV_64bitIntegers
    /* version if 64-bit integers supported */
typedef struct FNV64context_s {
        int Computed;  /* state */
        uint64_t Hash;
} FNV64context;

#else
    /* version if 64-bit integers NOT supported */
typedef struct FNV64context_s {
        int Computed;  /* state */
        uint16_t Hash[FNV64size/2];
} FNV64context;

#endif /* FNV_64bitIntegers */

/*
 *  Function Prototypes:
 *
 *    FNV64string: hash a zero-terminated string not including
 *                 the terminating zero
 *    FNV64block: hash a specified length byte vector
 *    FNV64file: hash the contents of a file
 *
 *    FNV64init: initializes an FNV64 context
 *    FNV64initBasis: initializes an FNV64 context with a
 *                    provided 8-byte vector basis
 *    FNV64blockin: hash in a specified length byte vector
 *    FNV64stringin: hash in a zero-terminated string not
 *                   including the terminating zero
 *    FNV64result: returns the hash value
 *
 * Hash is returned as an 8-byte vector by the functions above.
 *    If 64-bit integers are supported, the following return
 *    a 64-bit integer.
 *
 *    FNV64INTstring: hash a zero-terminated string not including
 *                 the terminating zero
 *    FNV64INTblock: hash a specified length byte vector
 *    FNV64INTfile: hash the contents of a file
 *
 *    FNV64INTinitBasis: initializes an FNV32 context with a
 *                     provided 64-bit integer basis
 *    FNV64INTresult: returns the hash value
 */

#ifdef __cplusplus
extern "C" {
#endif

/* FNV64 */
extern int FNV64init ( FNV64context * const );
extern int FNV64blockin ( FNV64context * const,
                          const void * vin,
                          long int length );
extern int FNV64stringin ( FNV64context * const,
                           const char * in );

#ifdef FNV_64bitIntegers
  extern int FNV64INTstring ( const char *in,
                           uint64_t * const out );
  extern int FNV64INTblock ( const void *vin,
                          long int length,
                          uint64_t * const out );
  extern int FNV64INTfile ( const char * fname,
                         uint64_t * const out );
  extern int FNV64INTinitBasis ( FNV64context * const,
                            uint64_t basis );
  extern int FNV64INTresult ( FNV64context * const,
                           uint64_t * const out );
#endif /* FNV_64bitIntegers */

  extern int FNV64string ( const char *in,
                           uint8_t out[FNV64size] );
  extern int FNV64block ( const void *vin,
                          long int length,
                          uint8_t out[FNV64size] );
  extern int FNV64file ( const char * fname,
                         uint8_t out[FNV64size] );
  extern int FNV64initBasis ( FNV64context * const,
                            const uint8_t basis[FNV64size] );
  extern int FNV64result ( FNV64context * const,
                           uint8_t out[FNV64size] );

#ifdef __cplusplus
}
#endif

#endif /* _FNV64_H_ */

<CODE ENDS>
<CODE BEGINS> file "FNV64.c"


//*************************** FNV64.c ****************************//
//****************** See RFC NNNN for details ********************//
/* Copyright (c) 2016, 2024 IETF Trust and the persons
 * identified as authors of the code.  All rights reserved.
 * See fnv-private.h for terms of use and redistribution.
 */

/* This file implements the FNV (Fowler, Noll, Vo) non-cryptographic
 * hash function FNV-1a for 64-bit hashes.
 */

#include <stdio.h>

#include "FNVconfig.h"
#include "fnv-private.h"
#include "FNV64.h"


//*****************************************************************
// START VERSION FOR WHEN YOU HAVE 64-BIT ARITHMETIC
//*****************************************************************
#ifdef FNV_64bitIntegers

/* 64-bit FNV_prime = 2^40 + 2^8 + 0xb3 */
#define FNV64prime 0x00000100000001B3

/* FNV64 hash a zero-terminated string not including the zero
 * to a 64-bit integer  (64-bit)
 ******************************************************************/
int FNV64INTstring ( const char *in, uint64_t * const out ) {
    uint64_t    temp;
    uint8_t     ch;

    if ( !in || !out )
        return fnvNull; /* Null input pointer */
    temp = FNV64basis;
    while ( (ch = *in++) )
        temp = FNV64prime * ( temp ^ ch );
    *out = temp;
    return fnvSuccess;
}   /* end FNV64INTstring */

/* FNV64 hash a zero-terminated string to a 64-bit integer
 * to a byte vector  (64-bit)
 ******************************************************************/
int FNV64string ( const char *in, uint8_t out[FNV64size] ) {
    uint64_t    temp;
    uint8_t     ch;
    int         i;

    if ( !in || !out )
        return fnvNull; /* Null input pointer */
    temp = FNV64basis;
    while ( (ch = *in++) )
        temp = FNV64prime * ( temp ^ ch );
    for ( i=0; i<FNV64size; ++i )
        out[i] = ((uint8_t *)&temp)[i];
    return fnvSuccess;
}   /* end FNV64string */

/* FNV64 hash a counted block to a 64-bit integer  (64-bit)
 ******************************************************************/
int FNV64INTblock ( const void *vin,
                 long int length,
                 uint64_t * const out ) {
    const uint8_t *in = (const uint8_t*)vin;
    uint64_t    temp;

    if ( !in || !out )
        return fnvNull; /* Null input/out pointer */
    if ( length < 0 )
        return fnvBadParam;
    for ( temp = FNV64basis; length > 0; length-- )
        temp = FNV64prime * ( temp ^ *in++ );
    *out = temp;
    return fnvSuccess;
}   /* end FNV64INTblock */

/* FNV64 hash a counted block to a byte vector  (64-bit)
 ******************************************************************/
int FNV64block ( const void *vin,
                 long int length,
                 uint8_t out[FNV64size] ) {
    const uint8_t *in = (const uint8_t*)vin;
    uint64_t    temp;
    int         i;

    if ( !in || !out )
        return fnvNull; /* Null input/out pointer */
    if ( length < 0 )
        return fnvBadParam;
    for ( temp = FNV64basis; length > 0; length-- )
        temp = FNV64prime * ( temp ^ *in++ );
    for ( i=0; i<FNV64size; ++i )
        out[i] = ((uint8_t *)&temp)[i];
    return fnvSuccess;
}   /* end FNV64block */


//*****************************************************************
// Set of init, input, and output functions below
// to incrementally compute FNV64
//*****************************************************************

/* initialize context  (64-bit)
 ******************************************************************/
int FNV64init( FNV64context * const ctx ) {
    return FNV64INTinitBasis ( ctx, FNV64basis );
}       /* end FNV64init */

/* initialize context with a provided 64-bit integer basis  (64-bit)
 ******************************************************************/
int FNV64INTinitBasis( FNV64context * const ctx, uint64_t basis ) {
    if ( !ctx )
        return fnvNull;
    ctx->Hash = basis;
    ctx->Computed = FNVinited+FNV64state;
    return fnvSuccess;
}       /* end FNV64INTinitBasis */

/* initialize context with a provided 8-byte vector basis  (64-bit)
 ******************************************************************/
int FNV64initBasis( FNV64context * const ctx,
                    const uint8_t basis[FNV64size] ) {
    int     i;

    if ( !ctx )
        return fnvNull;
    for ( i=0; i<FNV64size; ++i )
        ((uint8_t *)&ctx->Hash)[i] = basis[i];
    ctx->Computed = FNVinited+FNV64state;
    return fnvSuccess;
}       /* end FNV64initBasis */

/* hash in a counted block  (64-bit)
 ******************************************************************/
int FNV64blockin( FNV64context * const ctx,
                   const void *vin,
                   long int length ) {
    const uint8_t *in = (const uint8_t*)vin;
    uint64_t    temp;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV64state:
            ctx->Computed = FNVcomputed+FNV64state;
            break;
        case FNVcomputed+FNV64state:
            break;
        default:
            return fnvStateError;
        }
    if ( length < 0 )
        return fnvBadParam;
    for ( temp = ctx->Hash; length > 0; length-- )
        temp = FNV64prime * ( temp ^ *in++ );
    ctx->Hash = temp;
    return fnvSuccess;
}   /* end FNV64blockin */

/* hash in a zero-terminated string not including the zero (64-bit)
 ******************************************************************/
int FNV64stringin ( FNV64context * const ctx, const char *in ) {
    uint64_t        temp;
    uint8_t         ch;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV64state:
            ctx->Computed = FNVcomputed+FNV64state;
            break;
        case FNVcomputed+FNV64state:
            break;
        default:
             return fnvStateError;
         }
    temp = ctx->Hash;
    while ( (ch = (uint8_t)*in++) )
        temp = FNV64prime * ( temp ^ ch );
    ctx->Hash = temp;
    return fnvSuccess;
}   /* end FNV64stringin */

/* return hash as 64-bit int (64-bit)
 ******************************************************************/
int FNV64INTresult ( FNV64context * const ctx,
                     uint64_t * const out ) {
    if ( !ctx || !out )
        return fnvNull;
    if ( ctx->Computed != FNVcomputed+FNV64state )
        return fnvStateError;
    ctx->Computed = FNVemptied+FNV64state;
    *out = ctx->Hash;
    ctx->Hash = 0;
    return fnvSuccess;
}   /* end FNV64INTresult */

/* return hash as 8-byte vector (64-bit)
 ******************************************************************/
int FNV64result ( FNV64context * const ctx,
                 uint8_t out[FNV64size] ) {
    int     i;

    if ( !ctx || !out )
        return fnvNull;
    if ( ctx->Computed != FNVcomputed+FNV64state )
        return fnvStateError;
    ctx->Computed = FNVemptied+FNV64state;
    for ( i=0; i<FNV64size; ++i )
        out[i] = ((uint8_t *)&ctx->Hash)[i];
    ctx->Hash = 0;
    return fnvSuccess;
}   /* end FNV64result */

/* hash the contents of a file, return 64-bit integer
 ******************************************************************/
int FNV64INTfile ( const char *fname,
                         uint64_t * const out ) {
    FILE *fp;
    long int i;
    char buf[1024];
    FNV64context e64Context;
    int error;

    if ( !fname || !out )
        return fnvNull;
    if ( ( fp = fopen ( fname, "rb") ) == NULL )
        return fnvBadParam;
    if ( (error = FNV64init (&e64Context)) ) {
        fclose(fp);
        return error;
    }
    if ( (error = FNV64blockin ( &e64Context, "", 0)) ) {
        fclose(fp);
        return error;
    }
    while ( ( i = fread ( buf, 1, sizeof(buf), fp ) ) > 0 )
        if ( (error = FNV64blockin ( &e64Context, buf, i)) ) {
            fclose(fp);
            return error;
        }
    error = ferror(fp);
    fclose(fp);
    if (error)
        return fnvBadParam;
    return FNV64INTresult ( &e64Context, out );
}   /* end FNV64INTfile */

/* hash the contents of a file, return 64-bit integer
 ******************************************************************/
int FNV64file ( const char *fname,
               uint8_t out[FNV64size] ) {
    uint64_t outINT;
    int i, err;

    if ( !out )
        return fnvNull;
    if ( (err = FNV64INTfile ( fname, &outINT)) )
        return err;
    for ( i=0; i<FNV64size; ++i )
        out[i] = ((uint8_t *)&outINT)[i];
    return fnvSuccess;
}   /* emd FNV64file */

//***************************************************************
// END VERSION FOR WHEN YOU HAVE 64-BIT ARITHMETIC
//***************************************************************
#else    /*  FNV_64bitIntegers */
//***************************************************************
// START VERSION FOR WHEN YOU ONLY HAVE 32-BIT ARITHMETIC
//***************************************************************

/* 64-bit FNV_prime = 2^40 + 2^8 + 0xb3 */
/* #define FNV64prime 0x00000100000001B3 */
#define FNV64primeX 0x01B3
#define FNV64shift 8

/* #define FNV64basis 0xCBF29CE484222325 */
#define FNV64basis0 0xCBF2
#define FNV64basis1 0x9CE4
#define FNV64basis2 0x8422
#define FNV64basis3 0x2325

/* FNV64 hash a zero-terminated string not including the zero
 ******************************************************************/
int FNV64string ( const char *in, uint8_t out[FNV64size] ) {
    FNV64context     ctx;
    int              err;

    if ( !in || !out )
        return fnvNull; /* Null input pointer */
    if ( ( err = FNV64init (&ctx) ) != fnvSuccess )
        return err;
    if ( ( err = FNV64stringin (&ctx, in) ) != fnvSuccess )
        return err;
    return FNV64result (&ctx, out);
}   /* end FNV64string */

/* FNV64 hash a counted block
 ******************************************************************/
int FNV64block ( const void *vin,
                 long int length,
                 uint8_t out[FNV64size] ) {
    FNV64context     ctx;
    int              err;

    if ( ( err = FNV64init (&ctx) ) != fnvSuccess )
        return err;
    if ( ( err = FNV64blockin (&ctx, vin, length) ) != fnvSuccess )
        return err;
    return FNV64result (&ctx, out);
}   /* end FNV64block */

//*****************************************************************
//        Set of init, input, and output functions below
//        to incrementally compute FNV64
//*****************************************************************

/* initialize context  (32-bit)
 ******************************************************************/
int FNV64init ( FNV64context * const ctx ) {
    if ( !ctx )
        return fnvNull;
    ctx->Hash[0] = FNV64basis0;
    ctx->Hash[1] = FNV64basis1;
    ctx->Hash[2] = FNV64basis2;
    ctx->Hash[3] = FNV64basis3;
    ctx->Computed = FNVinited+FNV64state;
    return fnvSuccess;
}   /* end FNV64init */

/* initialize context  (32-bit)
 ******************************************************************/
int FNV64initBasis ( FNV64context * const ctx,
                     const uint8_t basis[FNV64size] ) {
    if ( !ctx )
        return fnvNull;
    ctx->Hash[0] = basis[0] + ( basis[1]<<8 );
    ctx->Hash[1] = basis[2] + ( basis[3]<<8 );
    ctx->Hash[2] = basis[4] + ( basis[5]<<8 );
    ctx->Hash[3] = basis[6] + ( basis[7]<<8 );
    ctx->Computed = FNVinited+FNV64state;
    return fnvSuccess;
}   /* end FNV64initBasis */

/* hash in a counted block  (32-bit)
 ******************************************************************/
int FNV64blockin ( FNV64context * const ctx,
                   const void *vin,
                   long int length ) {
    const uint8_t *in = (const uint8_t*)vin;
    uint32_t   temp[FNV64size/2];
    uint32_t   temp2[2];
    int        i;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV64state:
            ctx->Computed = FNVcomputed+FNV64state;
            break;
        case FNVcomputed+FNV64state:
            break;
        default:
            return fnvStateError;
        }
    if ( length < 0 )
        return fnvBadParam;
    for ( i=0; i<FNV64size/2; ++i )
         temp[i] = ctx->Hash[i];
    for ( ; length > 0; length-- ) {
        /* temp = FNV64prime * ( temp ^ *in++ ); */
        temp[3] ^= *in++;
        temp2[1] = temp[3] << FNV64shift;
        temp2[0] = temp[2] << FNV64shift;
        temp[3] *= FNV64primeX;
        temp[2] *= FNV64primeX;
        temp[1] *= FNV64primeX;
        temp[0] *= FNV64primeX;
        temp[1] += temp2[1];
        temp[0] += temp2[0];
        temp[2] += temp[3] >> 16;
        temp[1] += temp[2] >> 16;
        temp[0] += temp[1] >> 16;
        temp[3] &= 0xFFFF;
        temp[2] &= 0xFFFF;
        temp[1] &= 0xFFFF;
        }
    for ( i=0; i<FNV64size/2; ++i )
        ctx->Hash[i] = temp[i];
    return fnvSuccess;
}   /* end FNV64blockin */

/* hash in a zero-terminated string not including the zero  (32-bit)
 ******************************************************************/
int FNV64stringin ( FNV64context * const ctx, const char *in ) {
    uint32_t   temp[FNV64size/2];
    uint32_t   temp2[2];
    int        i;
    uint8_t    ch;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV64state:
            ctx->Computed = FNVcomputed+FNV64state;
            break;
        case FNVcomputed+FNV64state:
            break;
        default:
             return fnvStateError;
         }
    for ( i=0; i<FNV64size/2; ++i )
         temp[i] = ctx->Hash[i];
    while ( ( ch = (uint8_t)*in++ ) ) {
        /* temp = FNV64prime * ( temp ^ ch ); */
        temp[3] ^= ch;
        temp2[1] = temp[3] << FNV64shift;
        temp2[0] = temp[2] << FNV64shift;
        temp[3] *= FNV64primeX;
        temp[2] *= FNV64primeX;
        temp[1] *= FNV64primeX;
        temp[0] *= FNV64primeX;
        temp[1] += temp2[1];
        temp[0] += temp2[0];
        temp[2] += temp[3] >> 16;
        temp[1] += temp[2] >> 16;
        temp[0] += temp[1] >> 16;
        temp[3] &= 0xFFFF;
        temp[2] &= 0xFFFF;
        temp[1] &= 0xFFFF;
        }
    for ( i=0; i<FNV64size/2; ++i )
        ctx->Hash[i] = temp[i];
    return fnvSuccess;
}   /* end FNV64stringin */

/* return hash  (32-bit)
 ******************************************************************/
int FNV64result ( FNV64context * const ctx,
                  uint8_t out[FNV64size] ) {
    int    i;

    if ( !ctx || !out )
        return fnvNull;
    if ( ctx->Computed != FNVcomputed+FNV64state )
        return fnvStateError;
    for ( i=0; i<FNV64size/2; ++i ) {
        out[2*i] = ctx->Hash[i] >> 8;
        out[2*i+1] = ctx->Hash[i];
        ctx -> Hash[i] = 0;
        }
    ctx->Computed = FNVemptied+FNV64state;
    return fnvSuccess;
}   /* end FNV64result */

/* hash the contents of a file  (32-bit)
 ******************************************************************/
int FNV64file ( const char *fname,
                      uint8_t out[FNV64size] ) {
    FILE    *fp;
    long int i;
    char buf[1024];
    FNV64context e64Context;
    int error;

    if ( !fname || !out )
        return fnvNull;
    if ( ( fp = fopen ( fname, "rb") ) == NULL )
        return fnvBadParam;
    if ( (error = FNV64init (&e64Context)) ) {
        fclose(fp);
        return error;
    }
    if ( (error = FNV64blockin ( &e64Context, "", 0)) ) {
        fclose(fp);
        return error;
    }
    while ( ( i = fread ( buf, 1, sizeof(buf), fp ) ) > 0 )
        if ( (error = FNV64blockin ( &e64Context, buf, i)) ) {
            fclose(fp);
            return error;
        }
    error = ferror(fp);
    fclose(fp);
    if (error)
        return fnvBadParam;
    return FNV64result ( &e64Context, out );
}   /* end FNV64file */

#endif    /*  FNV_64bitIntegers */
//*****************************************************************
// END VERSION FOR WHEN YOU ONLY HAVE 32-BIT ARITHMETIC
//*****************************************************************

<CODE ENDS>

6.2.3. FNV128 Code

The header and C source for 128-bit FNV-1a providing a byte vector hash.

<CODE BEGINS> file "FNV128.h"


//************************** FNV128.h ************************//
//*************** See RFC NNNN for details. ******************//
/* Copyright (c) 2016, 2024 IETF Trust and the persons
 * identified as authors of the code.  All rights reserved.
 * See fnv-private.h for terms of use and redistribution.
 */

#ifndef _FNV128_H_
#define _FNV128_H_

/*
 *  Description:
 *      This file provides headers for the 128-bit version of
 *      the FNV-1a non-cryptographic hash algorithm.
 */

#include "FNVconfig.h"
#include "FNVErrorCodes.h"

#include <stdint.h>
#define FNV128size (128/8)

/* If you do not have the ISO standard stdint.h header file, then
 * you must typedef the following types:
 *
 *    type              meaning
 *  uint64_t    unsigned 64-bit integer (ifdef FNV_64bitIntegers)
 *  uint32_t    unsigned 32-bit integer
 *  uint16_t    unsigned 16-bit integer
 *  uint8_t     unsigned 8-bit integer (i.e., unsigned char)
 */

/*
 *  This structure holds context information for an FNV128 hash
 */
#ifdef FNV_64bitIntegers
    /* version if 64-bit integers supported */
typedef struct FNV128context_s {
        int Computed;  /* state */
        uint32_t Hash[FNV128size/4];
} FNV128context;

#else
    /* version if 64-bit integers NOT supported */

typedef struct FNV128context_s {
        int Computed;  /* state */
        uint16_t Hash[FNV128size/2];
} FNV128context;

#endif /* FNV_64bitIntegers */

/*
 *  Function Prototypes:
 *
 *    FNV128string: hash a zero-terminated string not including
 *                  the terminating zero
 *    FNV128block: hash a specified length byte vector
 *    FNV128file: hash the contents of a file
 *
 *    FNV128init: initializes an FNV128 context
 *    FNV128initBasis: initializes an FNV128 context with a
 *                     provided 16-byte vector basis
 *    FNV128blockin: hash in a specified length byte vector
 *    FNV128stringin: hash in a zero-terminated string not
 *                    including the terminating zero
 *    FNV128result: returns the hash value
 *
 *    Hash is returned as an array of 8-bit unsigned integers
 */

#ifdef __cplusplus
extern "C" {
#endif

/* FNV128 */
extern int FNV128string ( const char *in,
                          uint8_t out[FNV128size] );
extern int FNV128block ( const void *vin,
                         long int length,
                         uint8_t out[FNV128size] );
extern int FNV128file ( const char *fname,
                        uint8_t out[FNV128size] );
extern int FNV128init ( FNV128context * const );
extern int FNV128initBasis ( FNV128context * const,
                             const uint8_t basis[FNV128size] );
extern int FNV128blockin ( FNV128context * const,
                           const void *vin,
                           long int length );
extern int FNV128stringin ( FNV128context * const,
                            const char *in );
extern int FNV128result ( FNV128context * const,
                          uint8_t out[FNV128size] );

#ifdef __cplusplus
}
#endif

#endif /* _FNV128_H_ */

<CODE ENDS>
<CODE BEGINS> file "FNV128.c"


//**************************** FNV128.c **************************//
//******************* See RFC NNNN for details *******************//
/* Copyright (c) 2016, 2024 IETF Trust and the persons
 * identified as authors of the code.  All rights reserved.
 * See fnv-private.h for terms of use and redistribution.
 */

/* This file implements the FNV (Fowler, Noll, Vo) non-cryptographic
 * hash function FNV-1a for 128-bit hashes.
 */

#include <stdio.h>

#include "FNVconfig.h"
#include "fnv-private.h"
#include "FNV128.h"

//*****************************************************************
// COMMON CODE FOR 64- AND 32-BIT INTEGER MODES
//*****************************************************************

/* FNV128 hash a zero-terminated string not including the zero
 ******************************************************************/
int FNV128string ( const char *in, uint8_t out[FNV128size] ) {
    FNV128context    ctx;
    int              err;

    if ( (err = FNV128init ( &ctx )) != fnvSuccess )
        return err;
    if ( (err = FNV128stringin ( &ctx, in )) != fnvSuccess )
        return err;
    return FNV128result (&ctx, out);
}   /* end FNV128string */

/* FNV128 hash a counted block  (64/32-bit)
 ******************************************************************/
int FNV128block ( const void *vin,
                  long int length,
                  uint8_t out[FNV128size] ) {
    FNV128context    ctx;
    int              err;

    if ( (err = FNV128init ( &ctx )) != fnvSuccess )
        return err;
    if ( (err = FNV128blockin ( &ctx, vin, length )) != fnvSuccess )
        return err;
    return FNV128result ( &ctx, out );
}   /* end FNV128block */

/* hash the contents of a file
 ******************************************************************/
int FNV128file ( const char *fname,
                       uint8_t out[FNV128size] ) {
    FILE *fp;
    long int i;
    char buf[1024];
    FNV128context e128Context;
    int error;

    if ( !fname || !out )
        return fnvNull;
    if ( ( fp = fopen ( fname, "rb") ) == NULL )
        return fnvBadParam;
    if ( (error = FNV128init (&e128Context)) ) {
        fclose(fp);
        return error;
    }
    if ( (error = FNV128blockin ( &e128Context, "", 0)) ) {
        fclose(fp);
        return error;
    }
    while ( ( i = fread ( buf, 1, sizeof(buf), fp ) ) > 0 )
        if ( (error = FNV128blockin ( &e128Context, buf, i)) ) {
            fclose(fp);
            return error;
        }
    error = ferror(fp);
    fclose(fp);
    if (error)
        return fnvBadParam;
    return FNV128result ( &e128Context, out );
}   /* end FNV128file */

//*****************************************************************
//        START VERSION FOR WHEN YOU HAVE 64-BIT ARITHMETIC
//*****************************************************************
#ifdef FNV_64bitIntegers

/* 128-bit FNV_prime = 2^88 + 2^8 + 0x3b */
/* 0x00000000 01000000 00000000 0000013B */
#define FNV128primeX 0x013B
#define FNV128shift 24

/* 0x6C62272E 07BB0142 62B82175 6295C58D */
#define FNV128basis0 0x6C62272E
#define FNV128basis1 0x07BB0142
#define FNV128basis2 0x62B82175
#define FNV128basis3 0x6295C58D

//*****************************************************************
//         Set of init, input, and output functions below
//         to incrementally compute FNV128
//*****************************************************************/

/* initialize context  (64-bit)
 ******************************************************************/
int FNV128init ( FNV128context * const ctx ) {
    if ( !ctx )
        return fnvNull;
    ctx->Hash[0] = FNV128basis0;
    ctx->Hash[1] = FNV128basis1;
    ctx->Hash[2] = FNV128basis2;
    ctx->Hash[3] = FNV128basis3;
    ctx->Computed = FNVinited+FNV128state;
    return fnvSuccess;
}   /* end FNV128init */

/* initialize context with a provided 16-byte vector basis  (64-bit)
 ******************************************************************/
int FNV128initBasis ( FNV128context * const ctx,
                      const uint8_t basis[FNV128size] ) {
    int       i;
    const uint8_t   *ui8p;

    if ( !ctx )
        return fnvNull;
    ui8p = basis + ( FNV128size/4 - 1 );
    for ( i=0; i < FNV128size/4; ++i ) {
            uint32_t  temp = (*ui8p--)<<8;
            temp = (temp + *ui8p--)<<8;
            temp = (temp + *ui8p--)<<8;
        ctx->Hash[i] = temp +  *ui8p;
        }
    ctx->Computed = FNVinited+FNV128state;
    return fnvSuccess;
}   /* end FNV128initBasis */

/* hash in a counted block  (64-bit)
 ******************************************************************/
int FNV128blockin ( FNV128context * const ctx,
                    const void *vin,
                    long int length ) {
    const uint8_t *in = (const uint8_t*)vin;
    uint64_t    temp[FNV128size/4];
    uint64_t    temp2[2];
    int         i;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV128state:
            ctx->Computed = FNVcomputed+FNV128state;
            break;
        case FNVcomputed+FNV128state:
            break;
        default:
            return fnvStateError;
        }
    if ( length < 0 )
        return fnvBadParam;
    for ( i=0; i<FNV128size/4; ++i )
         temp[i] = ctx->Hash[i];
    for ( ; length > 0; length-- ) {
        /* temp = FNV128prime * ( temp ^ *in++ ); */
        temp[FNV128size/4-1] ^= *in++;
        temp2[1] = temp[3] << FNV128shift;
        temp2[0] = temp[2] << FNV128shift;
        for ( i=0; i < FNV128size/4; ++i )
            temp[i] *= FNV128primeX;
        temp[1] += temp2[1];
        temp[0] += temp2[0];
        temp[2] += temp[3] >> 32;
        temp[1] += temp[2] >> 32;
        temp[0] += temp[1] >> 32;
        temp[3] &= 0xFFFFFFFF;
        temp[2] &= 0xFFFFFFFF;
        temp[1] &= 0xFFFFFFFF;
        }
    for ( i=0; i<FNV128size/4; ++i )
        ctx->Hash[i] = (uint32_t)temp[i];
    return fnvSuccess;
}   /* end FNV128blockin */

/* hash in a zero-terminated string not including the zero  (64-bit)
 ******************************************************************/
int FNV128stringin ( FNV128context * const ctx, const char *in ) {
    uint64_t   temp[FNV128size/4];
    uint64_t   temp2[2];
    int        i;
    uint8_t    ch;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV128state:
            ctx->Computed = FNVcomputed+FNV128state;
            break;
        case FNVcomputed+FNV128state:
            break;
        default:
             return fnvStateError;
         }
    for ( i=0; i<FNV128size/4; ++i )
         temp[i] = ctx->Hash[i];
    while ( ( ch = (uint8_t)*in++ ) ) {
        /* temp = FNV128prime * ( temp ^ ch ); */
        temp[3] ^= ch;
        temp2[1] = temp[3] << FNV128shift;
        temp2[0] = temp[2] << FNV128shift;
        for ( i=0; i < FNV128size/4; ++i )
            temp[i] *= FNV128primeX;
        temp[1] += temp2[1];
        temp[0] += temp2[0];
        temp[2] += temp[3] >> 32;
        temp[1] += temp[2] >> 32;
        temp[0] += temp[1] >> 32;
        temp[3] &= 0xFFFFFFFF;
        temp[2] &= 0xFFFFFFFF;
        temp[1] &= 0xFFFFFFFF;
        }
    for ( i=0; i<FNV128size/4; ++i )
        ctx->Hash[i] = (uint32_t)temp[i];
    return fnvSuccess;
}   /* end FNV128stringin */

/* return hash as 16-byte vector   (64-bit)
 ******************************************************************/
int FNV128result ( FNV128context * const ctx,
                   uint8_t out[FNV128size] ) {
    int     i;

    if ( !ctx || !out )
        return fnvNull;
    if ( ctx->Computed != FNVcomputed+FNV128state )
        return fnvStateError;
    for ( i=0; i<FNV128size/4; ++i ) {
        out[4*i] = ctx->Hash[i] >> 24;
        out[4*i+1] = ctx->Hash[i] >> 16;
        out[4*i+2] = ctx->Hash[i] >> 8;
        out[4*i+3] = ctx->Hash[i];
        ctx -> Hash[i] = 0;
        }
    ctx->Computed = FNVemptied+FNV128state;
    return fnvSuccess;
}   /* end FNV128result */

//****************************************************************
// END VERSION FOR WHEN YOU HAVE 64-BIT ARITHMETIC
//****************************************************************
#else    /*  FNV_64bitIntegers */
//****************************************************************
// START VERSION FOR WHEN YOU ONLY HAVE 32-BIT ARITHMETIC
//****************************************************************

/* 128-bit FNV_prime = 2^88 + 2^8 + 0x3b */
/* 0x00000000 01000000 00000000 0000013B */
#define FNV128primeX 0x013B
#define FNV128shift 8

/* 0x6C62272E 07BB0142 62B82175 6295C58D */
uint16_t FNV128basis[FNV128size/2] =
         { 0x6C62, 0x272E, 0x07BB, 0x0142,
           0x62B8, 0x2175, 0x6295, 0xC58D };

//*****************************************************************
//         Set of init, input, and output functions below
//         to incrementally compute FNV128
//*****************************************************************

/* initialize context  (32-bit)
 ******************************************************************/
int FNV128init ( FNV128context * const ctx ) {
    int     i;

    if ( !ctx )
        return fnvNull;
    for ( i=0; i<FNV128size/2; ++i )
        ctx->Hash[i] = FNV128basis[i];
    ctx->Computed = FNVinited+FNV128state;
    return fnvSuccess;
}   /* end FNV128init */

/* initialize context with a provided 16-byte vector basis  (32-bit)
 ******************************************************************/
int FNV128initBasis ( FNV128context * const ctx,
                      const uint8_t basis[FNV128size] ) {
    int      i;
    const uint8_t  *ui8p;

    if ( !ctx )
        return fnvNull;
    ui8p = basis + (FNV128size/2 - 1);
    for ( i=0; i < FNV128size/2; ++i ) {
        uint32_t temp = *ui8p--;
        ctx->Hash[i] = ( temp<<8 ) +  (*ui8p--);
        }
    ctx->Computed = FNVinited+FNV128state;
    return fnvSuccess;
}   /* end FNV128initBasis */

/* hash in a counted block  (32-bit)
 *****************************************************************/
int FNV128blockin ( FNV128context * const ctx,
                    const void *vin,
                    long int length ) {
    const uint8_t *in = (const uint8_t*)vin;
    uint32_t   temp[FNV128size/2];
    uint32_t   temp2[3];
    int        i;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV128state:
            ctx->Computed = FNVcomputed+FNV128state;
            break;
        case FNVcomputed+FNV128state:
            break;
        default:
            return fnvStateError;
        }
    if ( length < 0 )
        return fnvBadParam;
    for ( i=0; i < FNV128size/2; ++i )
         temp[i] = ctx->Hash[i];
    for ( ; length > 0; length-- ) {
        /* temp = FNV128prime * ( temp ^ *in++ ); */
        temp[FNV128size/2-1] ^= *in++;
        temp2[2] = temp[7] << FNV128shift;
        temp2[1] = temp[6] << FNV128shift;
        temp2[0] = temp[5] << FNV128shift;
        for ( i=0; i < (FNV128size/2); ++i )
            temp[i] *= FNV128primeX;
        temp[2] += temp2[2];
        temp[1] += temp2[1];
        temp[0] += temp2[0];
        for ( i=FNV128size/2-1; i>0; --i ) {
            temp[i-1] += temp[i] >> 16;
            temp[i] &= 0xFFFF;
            }
        }
    for ( i=0; i < FNV128size/2; ++i )
        ctx->Hash[i] = temp[i];
    return fnvSuccess;
}   /* end FNV128blockin */

/* hash in a zero-terminated string not including the zero  (32-bit)
 ******************************************************************/
int FNV128stringin ( FNV128context * const ctx, const char *in ) {
    uint32_t   temp[FNV128size/2];
    uint32_t   temp2[3];
    int        i;
    uint8_t    ch;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV128state:
            ctx->Computed = FNVcomputed+FNV128state;
            break;
        case FNVcomputed+FNV128state:
            break;
        default:
             return fnvStateError;
         }
    for ( i=0; i < FNV128size/2; ++i )
         temp[i] = ctx->Hash[i];
    while ( ( ch = (uint8_t)*in++ ) ) {
        /* temp = FNV128prime * ( temp ^ *in++ ); */
        temp[FNV128size/2-1] ^= ch;
        temp2[2] = temp[7] << FNV128shift;
        temp2[1] = temp[6] << FNV128shift;
        temp2[0] = temp[5] << FNV128shift;
        for ( i=0; i<(FNV128size/2); ++i )
            temp[i] *= FNV128primeX;
        temp[2] += temp2[2];
        temp[1] += temp2[1];
        temp[0] += temp2[0];
        for ( i=FNV128size/2-1; i>0; --i ) {
            temp[i-1] += temp[i] >> 16;
            temp[i] &= 0xFFFF;
            }
         }
    for ( i=0; i < FNV128size/2; ++i )
        ctx->Hash[i] = temp[i];
    return fnvSuccess;
}   /* end FNV128stringin */

/* return hash  (32-bit)
 ******************************************************************/
int FNV128result ( FNV128context * const ctx,
                   uint8_t out[FNV128size] ) {
    int    i;

    if ( !ctx || !out )
        return fnvNull;
    if ( ctx->Computed != FNVcomputed+FNV128state )
        return fnvStateError;
    for ( i=0; i<FNV128size/2; ++i ) {
        out[2*i] = ctx->Hash[i] >> 8;
        out[2*i+1] = ctx->Hash[i];
        ctx -> Hash[i] = 0;
        }
    ctx->Computed = FNVemptied+FNV128state;
    return fnvSuccess;
}   /* end FNV128result */

#endif    /*  FNV_64bitIntegers */
//******************************************************************
//        END VERSION FOR WHEN YOU ONLY HAVE 32-BIT ARITHMETIC
//******************************************************************

<CODE ENDS>

6.2.4. FNV256 Code

The header and C source for 256-bit FNV-1a providing a byte vector hash.

<CODE BEGINS> file "FNV256.h"


//************************* FNV256.h ***********************//
//************** See RFC NNNN for details. *****************//
/* Copyright (c) 2016, 2024 IETF Trust and the persons
 * identified as authors of the code.  All rights reserved.
 * See fnv-private.h for terms of use and redistribution.
 */

#ifndef _FNV256_H_
#define _FNV256_H_

/*
 *  Description:
 *      This file provides headers for the 256-bit version of
 *      the FNV-1a non-cryptographic hash algorithm.
 */

#include "FNVconfig.h"
#include "FNVErrorCodes.h"

#include <stdint.h>
#define FNV256size (256/8)

/* If you do not have the ISO standard stdint.h header file, then
 * you must typedef the following types:
 *
 *    type              meaning
 *  uint64_t    unsigned 64-bit integer (ifdef FNV_64bitIntegers)
 *  uint32_t    unsigned 32-bit integer
 *  uint16_t    unsigned 16-bit integer
 *  uint8_t     unsigned 8-bit integer (i.e., unsigned char)
 */

/*
 *  This structure holds context information for an FNV256 hash
 */
#ifdef FNV_64bitIntegers
    /* version if 64-bit integers supported */
typedef struct FNV256context_s {
        int Computed;  /* state */
        uint32_t Hash[FNV256size/4];
} FNV256context;

#else
    /* version if 64-bit integers NOT supported */

typedef struct FNV256context_s {
        int Computed;  /* state */
        uint16_t Hash[FNV256size/2];
} FNV256context;

#endif /* FNV_64bitIntegers */

/*
 *  Function Prototypes:
 *
 *    FNV256string: hash a zero-terminated string not including
 *                  the terminating zero
 *    FNV256block: hash a specified length byte vector
 *    FNV256file: hash the contents of a file
 *
 *    FNV256init: initializes an FNV256 context
 *    FNV256initBasis:  initializes an FNV256 context with a
 *                     provided 32-byte vector basis
 *    FNV256blockin: hash in a specified length byte vector
 *    FNV256stringin: hash in a zero-terminated string not
 *                    including the terminating zero
 *    FNV256result: returns the hash value
 *
 *    Hash is returned as an array of 8-bit unsigned integers
 */

#ifdef __cplusplus
extern "C" {
#endif

/* FNV256 */
extern int FNV256string ( const char *in,
                          uint8_t out[FNV256size] );
extern int FNV256block ( const void *vin,
                         long int length,
                         uint8_t out[FNV256size] );
extern int FNV256file ( const char *fname,
                        uint8_t out[FNV256size] );
extern int FNV256init ( FNV256context * const );
extern int FNV256initBasis ( FNV256context * const,
                             const uint8_t basis[FNV256size] );
extern int FNV256blockin ( FNV256context * const,
                           const void *vin,
                           long int length );
extern int FNV256stringin ( FNV256context * const,
                            const char *in );
extern int FNV256result ( FNV256context * const,
                          uint8_t out[FNV256size] );

#ifdef __cplusplus
}
#endif

#endif /* _FNV256_H_ */

<CODE ENDS>
<CODE BEGINS> file "FNV256.c"


//**************************** FNV256.c **************************//
//******************* See RFC NNNN for details *******************//
/* Copyright (c) 2016, 2024 IETF Trust and the persons
 * identified as authors of the code.  All rights reserved.
 * See fnv-private.h for terms of use and redistribution.
 */

/* This file implements the FNV (Fowler, Noll, Vo) non-cryptographic
 * hash function FNV-1a for 256-bit hashes.
 */

#include <stdio.h>

#include "fnv-private.h"
#include "FNV256.h"

//*****************************************************************
//  COMMON CODE FOR 64- AND 32-BIT INTEGER MODES
//*****************************************************************

/* FNV256 hash a zero-terminated string not including the zero
 ******************************************************************/
int FNV256string ( const char *in, uint8_t out[FNV256size] ) {
    FNV256context    ctx;
    int              err;

    if ( (err = FNV256init ( &ctx )) != fnvSuccess )
        return err;
    if ( (err = FNV256stringin ( &ctx, in )) != fnvSuccess )
        return err;
    return FNV256result ( &ctx, out );
}   /* end FNV256string */

/* FNV256 hash a counted block  (64/32-bit)
 ******************************************************************/
int FNV256block ( const void *vin,
                  long int length,
                  uint8_t out[FNV256size] ) {
    FNV256context    ctx;
    int              err;

    if ( (err = FNV256init ( &ctx )) != fnvSuccess )
        return err;
    if ( (err = FNV256blockin ( &ctx, vin, length)) != fnvSuccess )
        return err;
    return FNV256result ( &ctx, out );
}   /* end FNV256block */

/* hash the contents of a file
 ******************************************************************/
int FNV256file ( const char *fname,
                        uint8_t out[FNV256size] ) {
    FILE *fp;
    long int i;
    char buf[1024];
    FNV256context e256Context;
    int error;

    if ( !fname || !out )
        return fnvNull;
    if ( ( fp = fopen ( fname, "rb") ) == NULL )
        return fnvBadParam;
    if ( (error=FNV256init (&e256Context)) ) {
        fclose(fp);
        return error;
    }
    if ( (error = FNV256blockin ( &e256Context, "", 0)) ) {
        fclose(fp);
        return error;
    }
    while ( ( i = fread ( buf, 1, sizeof(buf), fp ) ) > 0 )
        if ( (error = FNV256blockin ( &e256Context, buf, i)) ) {
            fclose(fp);
            return error;
        }
    error = ferror(fp);
    fclose(fp);
    if (error)
        return fnvBadParam;
    return FNV256result ( &e256Context, out );
}   /* end FNV256file */

//*****************************************************************
//        START VERSION FOR WHEN YOU HAVE 64-BIT ARITHMETIC
//*****************************************************************
#ifdef FNV_64bitIntegers

/* 256-bit FNV_prime = 2^168 + 2^8 + 0x63 */
/* 0x0000000000000000 0000010000000000
     0000000000000000 0000000000000163 */
#define FNV256primeX 0x0163
#define FNV256shift 8

uint32_t FNV256basis[FNV256size/4] = {
         0xDD268DBC, 0xAAC55036, 0x2D98C384, 0xC4E576CC,
         0xC8B15368, 0x47B6BBB3, 0x1023B4C8, 0xCAEE0535 };

//*****************************************************************
//         Set of init, input, and output functions below
//         to incrementally compute FNV256
//*****************************************************************

/* initialize context  (64-bit)
 ******************************************************************/
int FNV256init ( FNV256context * const ctx ) {
    int      i;

    if ( !ctx )
        return fnvNull;
    for ( i=0; i<FNV256size/4; ++i )
        ctx->Hash[i] = FNV256basis[i];
    ctx->Computed = FNVinited+FNV256state;
    return fnvSuccess;
}   /* end FNV256init */

/* initialize context with a provided 32-byte vector basis  (64-bit)
 ******************************************************************/
int FNV256initBasis ( FNV256context * const ctx,
                      const uint8_t basis[FNV256size] ) {
    int      i;
    const uint8_t  *ui8p;

    if ( !ctx )
        return fnvNull;
    ui8p = basis + (FNV256size/4 - 1);
    for ( i=0; i < FNV256size/4; ++i ) {
        uint32_t  temp = (*ui8p--)<<8;
        temp = (temp + *ui8p--)<<8;
        temp = (temp + *ui8p--)<<8;
        ctx->Hash[i] = temp +  *ui8p;
        }
    ctx->Computed = FNVinited+FNV256state;
    return fnvSuccess;
}   /* end FNV256initBasis */

/* hash in a counted block  (64-bit)
 ******************************************************************/
int FNV256blockin ( FNV256context * const ctx,
                    const void *vin,
                    long int length ) {
    const uint8_t *in = (const uint8_t*)vin;
    uint64_t    temp[FNV256size/4];
    uint64_t    temp2[3];
    int         i;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV256state:
            ctx->Computed = FNVcomputed+FNV256state;
            break;
        case FNVcomputed+FNV256state:
            break;
        default:
            return fnvStateError;
        }
    if ( length < 0 )
        return fnvBadParam;
    for ( i=0; i<FNV256size/4; ++i )
         temp[i] = ctx->Hash[i];
    for ( ; length > 0; length-- ) {
        /* temp = FNV256prime * ( temp ^ *in++ ); */
        temp[FNV256size/4-1] ^= *in++;
        temp2[2] = temp[7] << FNV256shift;
        temp2[1] = temp[6] << FNV256shift;
        temp2[0] = temp[5] << FNV256shift;
        for ( i=0; i < FNV256size/4; ++i )
            temp[i] *= FNV256primeX;
        temp[2] += temp2[2];
        temp[1] += temp2[1];
        temp[0] += temp2[0];
        for ( i=FNV256size/4-1; i>0; --i ) {
            temp[i-1] += temp[i] >> 32;
            temp[i] &= 0xFFFFFFFF;
            }
       }
    for ( i=0; i<FNV256size/4; ++i )
        ctx->Hash[i] = (uint32_t)temp[i];
    return fnvSuccess;
}   /* end FNV256blockin */

/* hash in a zero-terminated string not including the zero  (64-bit)
 ******************************************************************/
int FNV256stringin ( FNV256context * const ctx, const char *in ) {
    uint64_t   temp[FNV256size/4];
    uint64_t   temp2[3];
    int        i;
    uint8_t    ch;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV256state:
            ctx->Computed = FNVcomputed+FNV256state;
            break;
        case FNVcomputed+FNV256state:
            break;
        default:
             return fnvStateError;
         }
    for ( i=0; i<FNV256size/4; ++i )
         temp[i] = ctx->Hash[i];
    while ( (ch = (uint8_t)*in++) ) {
        /* temp = FNV256prime * ( temp ^ ch ); */
        temp[FNV256size/4-1] ^= ch;
        temp2[2] = temp[7] << FNV256shift;
        temp2[1] = temp[6] << FNV256shift;
        temp2[0] = temp[5] << FNV256shift;
        for ( i=0; i<FNV256size/4; ++i )
            temp[i] *= FNV256primeX;
        temp[2] += temp2[2];
        temp[1] += temp2[1];
        temp[0] += temp2[0];
        for ( i=FNV256size/4-1; i>0; --i ) {
            temp[i-1] += temp[i] >> 32;
            temp[i] &= 0xFFFFFFFF;
            }
       }
    for ( i=0; i<FNV256size/4; ++i )
        ctx->Hash[i] = (uint32_t)temp[i];
    return fnvSuccess;
}   /* end FNV256stringin */

/* return hash as 8-byte vector  (64-bit)
 ******************************************************************/
int FNV256result ( FNV256context * const ctx,
                   uint8_t out[FNV256size] ) {
    int     i;

    if ( !ctx || !out )
        return fnvNull;
    if ( ctx->Computed != FNVcomputed+FNV256state )
        return fnvStateError;
    for ( i=0; i<FNV256size/4; ++i ) {
        out[4*i] = ctx->Hash[i] >> 24;
        out[4*i+1] = ctx->Hash[i] >> 16;
        out[4*i+2] = ctx->Hash[i] >> 8;
        out[4*i+3] = ctx->Hash[i];
        ctx -> Hash[i] = 0;
        }
    ctx->Computed = FNVemptied+FNV256state;
    return fnvSuccess;
}   /* end FNV256result */

//****************************************************************
//       END VERSION FOR WHEN YOU HAVE 64-BIT ARITHMETIC
//****************************************************************
#else    /*  FNV_64bitIntegers */
//****************************************************************
//       START VERSION FOR WHEN YOU ONLY HAVE 32-BIT ARITHMETIC
//****************************************************************

/* version for when you only have 32-bit arithmetic
 *****************************************************************/

/* 256-bit FNV_prime = 2^168 + 2^8 + 0x63 */
/* 0x00000000 00000000 00000100 00000000
     00000000 00000000 00000000 00000163 */
#define FNV256primeX 0x0163
#define FNV256shift 8

/* 0xDD268DBCAAC55036 2D98C384C4E576CC
     C8B1536847B6BBB3 1023B4C8CAEE0535 */
uint16_t FNV256basis[FNV256size/2] = {
         0xDD26, 0x8DBC, 0xAAC5, 0x5036,
         0x2D98, 0xC384, 0xC4E5, 0x76CC,
         0xC8B1, 0x5368, 0x47B6, 0xBBB3,
         0x1023, 0xB4C8, 0xCAEE, 0x0535 };

//****************************************************************
//       Set of init, input, and output functions below
//       to incrementally compute FNV256
//****************************************************************

/* initialize context  (32-bit)
 *****************************************************************/
int FNV256init ( FNV256context * const ctx ) {
    int     i;

    if ( !ctx )
        return fnvNull;
    for ( i=0; i<FNV256size/2; ++i )
        ctx->Hash[i] = FNV256basis[i];
    ctx->Computed = FNVinited+FNV256state;
    return fnvSuccess;
}   /* end FNV256init */

/* initialize context with a provided 32-byte vector basis  (32-bit)
 *****************************************************************/
int FNV256initBasis ( FNV256context * const ctx,
                      const uint8_t basis[FNV256size] ) {
    int      i;
    const uint8_t  *ui8p;

    if ( !ctx )
        return fnvNull;
    ui8p = basis + FNV256size/2 -1;
    for ( i=0; i < FNV256size/2; ++i ) {
        uint32_t temp = *ui8p--;
        ctx->Hash[i] = ( temp<<8 ) +  (*ui8p--);
        }
    ctx->Computed = FNVinited+FNV256state;
    return fnvSuccess;
}   /* end FNV256initBasis */

/* hash in a counted block  (32-bit)
 *****************************************************************/
int FNV256blockin ( FNV256context * const ctx,
                    const void *vin,
                    long int length ) {
    const uint8_t *in = (const uint8_t*)vin;
    uint32_t   temp[FNV256size/2];
    uint32_t   temp2[6];
    int        i;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV256state:
            ctx->Computed = FNVcomputed+FNV256state;
            break;
        case FNVcomputed+FNV256state:
            break;
        default:
            return fnvStateError;
        }
    if ( length < 0 )
        return fnvBadParam;
    for ( i=0; i<FNV256size/2; ++i )
        temp[i] = ctx->Hash[i];
    for ( ; length > 0; length-- ) {
        /* temp = FNV256prime * ( temp ^ *in++ ); */
        temp[FNV256size/2-1] ^= *in++;
        for ( i=0; i<6; ++i )
            temp2[5-i] = temp[FNV256size/2-1-i] << FNV256shift;
        for ( i=0; i<FNV256size/2; ++i )
            temp[i] *= FNV256primeX;
        for ( i=0; i<6; ++i )
            temp[i] += temp2[i];
        for ( i=FNV256size/2-1; i>0; --i ) {
            temp[i-1] += temp[i] >> 16;
            temp[i] &= 0xFFFF;
            }
        }
    for ( i=0; i<FNV256size/2; ++i )
        ctx->Hash[i] = temp[i];
    return fnvSuccess;
}   /* end FNV256blockin */

/* hash in a zero-terminated string not including the zero  (32-bit)
 *****************************************************************/
int FNV256stringin ( FNV256context * const ctx, const char *in ) {
    uint32_t   temp[FNV256size/2];
    uint32_t   temp2[6];
    int        i;
    uint8_t    ch;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV256state:
            ctx->Computed = FNVcomputed+FNV256state;
            break;
        case FNVcomputed+FNV256state:
            break;
        default:
             return fnvStateError;
         }
    for ( i=0; i<FNV256size/2; ++i )
         temp[i] = ctx->Hash[i];
    while ( ( ch = (uint8_t)*in++ ) ) {
        /* temp = FNV256prime * ( temp ^ *in++ ); */
        temp[FNV256size/2-1] ^= ch;
        for ( i=0; i<6; ++i )
            temp2[5-i] = temp[FNV256size/2-1-i] << FNV256shift;
        for ( i=0; i<FNV256size/2; ++i )
            temp[i] *= FNV256primeX;
        for ( i=0; i<6; ++i )
            temp[i] += temp2[i];
        for ( i=FNV256size/2-1; i>0; --i ) {
            temp[i-1] += temp[i] >> 16;
            temp[i] &= 0xFFFF;
            }
         }
    for ( i=0; i<FNV256size/2; ++i )
        ctx->Hash[i] = temp[i];
    return fnvSuccess;
}   /* end FNV256stringin */

/* return hash  (32-bit)
 *****************************************************************/
int FNV256result ( FNV256context * const ctx,
                   uint8_t out[FNV256size] ) {
    int    i;

    if ( !ctx || !out )
        return fnvNull;
    if ( ctx->Computed != FNVcomputed+FNV256state )
        return fnvStateError;
    for ( i=0; i<FNV256size/2; ++i ) {
        out[2*i] = ctx->Hash[i] >> 8;
        out[2*i+1] = ctx->Hash[i];
        ctx->Hash[i] = 0;
        }
    ctx->Computed = FNVemptied+FNV256state;
    return fnvSuccess;
}   /* end FNV256result */

#endif    /*  FNV_64bitIntegers */
//****************************************************************
//        END VERSION FOR WHEN YOU ONLY HAVE 32-BIT ARITHMETIC
//****************************************************************

<CODE ENDS>

6.2.5. FNV512 Code

The header and C source for 512-bit FNV-1a providing a byte vector hash.

<CODE BEGINS> file "FNV512.h"


//************************* FNV512.h ***********************//
//************** See RFC NNNN for details. *****************//
/* Copyright (c) 2016, 2024 IETF Trust and the persons
 * identified as authors of the code.  All rights reserved.
 * See fnv-private.h for terms of use and redistribution.
 */

#ifndef _FNV512_H_
#define _FNV512_H_

/*
 *  Description:
 *      This file provides headers for the 512-bit version of
 *      the FNV-1a non-cryptographic hash algorithm.
 */

#include "FNVconfig.h"
#include "FNVErrorCodes.h"

#include <stdint.h>
#define FNV512size (512/8)

/* If you do not have the ISO standard stdint.h header file, then
 * you must typedef the following types:
 *
 *    type              meaning
 *  uint64_t    unsigned 64-bit integer (ifdef FNV_64bitIntegers)
 *  uint32_t    unsigned 32-bit integer
 *  uint16_t    unsigned 16-bit integer
 *  uint8_t     unsigned 8-bit integer (i.e., unsigned char)
 */

/*
 *  This structure holds context information for an FNV512 hash
 */
#ifdef FNV_64bitIntegers
    /* version if 64-bit integers supported */
typedef struct FNV512context_s {
        int Computed;  /* state */
        uint32_t Hash[FNV512size/4];
} FNV512context;

#else
    /* version if 64-bit integers NOT supported */

typedef struct FNV512context_s {
        int Computed;  /* state */
        uint16_t Hash[FNV512size/2];
} FNV512context;

#endif /* FNV_64bitIntegers */

/*
 *  Function Prototypes:
 *
 *    FNV512string: hash a zero-terminated string not including
 *                  the terminating zero
 *    FNV512block: hash a specified length byte vector
 *    FNV512file: hash the contents of a file
 *
 *    FNV512init: initializes an FNV512 context
 *    FNV512initBasis: initializes an FNV512 context with a
 *                     provided 64-byte vector basis
 *    FNV512blockin: hash in a specified length byte vector
 *    FNV512stringin: hash in a zero-terminated string not
 *                    including the terminating zero
 *    FNV512result: returns the hash value
 *
 *    Hash is returned as an array of 8-bit unsigned integers
 */

#ifdef __cplusplus
extern "C" {
#endif

/* FNV512 */
extern int FNV512string ( const char *in,
                          uint8_t out[FNV512size] );
extern int FNV512block ( const void *vin,
                         long int length,
                         uint8_t out[FNV512size] );
extern int FNV512file ( const char *fname,
                        uint8_t out[FNV512size] );
extern int FNV512init ( FNV512context * const );
extern int FNV512initBasis ( FNV512context * const,
                             const uint8_t basis[FNV512size] );
extern int FNV512blockin ( FNV512context * const,
                           const void *vin,
                           long int length );
extern int FNV512stringin ( FNV512context * const,
                            const char *in );
extern int FNV512result ( FNV512context * const,
                          uint8_t out[FNV512size] );

#ifdef __cplusplus
}
#endif

#endif /* _FNV512_H_ */

<CODE ENDS>
<CODE BEGINS> file "FNV512.c"


//**************************** FNV512.c **************************//
//******************* See RFC NNNN for details *******************//
/* Copyright (c) 2016, 2024 IETF Trust and the persons
 * identified as authors of the code.  All rights reserved.
 * See fnv-private.h for terms of use and redistribution.
 */

/* This file implements the FNV (Fowler, Noll, Vo) non-cryptographic
 * hash function FNV-1a for 512-bit hashes.
 */

#include <stdio.h>

#include "fnv-private.h"
#include "FNV512.h"

//*****************************************************************
//  COMMON CODE FOR 64- AND 32-BIT INTEGER MODES
//*****************************************************************

/* FNV512 hash a zero-terminated string not including the zero
 ******************************************************************/
int FNV512string ( const char *in, uint8_t out[FNV512size] ) {
    FNV512context    ctx;
    int              err;

    if ( (err = FNV512init ( &ctx )) != fnvSuccess )
        return err;
    if ( (err = FNV512stringin ( &ctx, in )) != fnvSuccess )
        return err;
    return FNV512result ( &ctx, out );
}   /* end FNV512string */

/* FNV512 hash a counted block  (64/32-bit)
 ******************************************************************/
int FNV512block ( const void *vin,
                  long int length,
                  uint8_t out[FNV512size] ) {
    FNV512context    ctx;
    int              err;

    if ( (err = FNV512init ( &ctx )) != fnvSuccess )
        return err;
    if ( (err = FNV512blockin ( &ctx, vin, length)) != fnvSuccess )
        return err;
    return FNV512result ( &ctx, out );
}   /* end FNV512block */

/* hash the contents of a file
 ******************************************************************/
int FNV512file ( const char *fname,
                       uint8_t out[FNV512size] ) {
    FILE *fp;
    long int i;
    char buf[1024];
    FNV512context e512Context;
    int error;

    if ( !fname || !out )
        return fnvNull;
    if ( ( fp = fopen ( fname, "rb") ) == NULL )
        return fnvBadParam;
    if ( (error = FNV512init (&e512Context)) ) {
        fclose(fp);
        return error;
    }
    if ( (error = FNV512blockin ( &e512Context, "", 0)) ) {
        fclose(fp);
        return error;
    }
    while ( ( i = fread ( buf, 1, sizeof(buf), fp ) ) > 0 )
        if ( (error=FNV512blockin ( &e512Context, buf, i)) ) {
            fclose(fp);
            return error;
        }
    error = ferror(fp);
    fclose(fp);
    if (error)
        return fnvBadParam;
    return FNV512result ( &e512Context, out );
}   /* end FNV512file */

//*****************************************************************
//        START VERSION FOR WHEN YOU HAVE 64-BIT ARITHMETIC
//*****************************************************************
#ifdef FNV_64bitIntegers

/*
  512-bit FNV_prime = 2^344 + 2^8 + 0x57 =
   0x0000000000000000 0000000000000000
     0000000001000000 0000000000000000
     0000000000000000 0000000000000000
     0000000000000000 0000000000000157 */
#define FNV512primeX 0x0157
#define FNV512shift 24

/* 0xB86DB0B1171F4416 DCA1E50F309990AC
     AC87D059C9000000 0000000000000D21
     E948F68A34C192F6 2EA79BC942DBE7CE
     182036415F56E34B AC982AAC4AFE9FD9 */

uint32_t FNV512basis[FNV512size/4] = {
     0xB86DB0B1, 0x171F4416, 0xDCA1E50F, 0x309990AC,
     0xAC87D059, 0xC9000000, 0x00000000, 0x00000D21,
     0xE948F68A, 0x34C192F6, 0x2EA79BC9, 0x42DBE7CE,
     0x18203641, 0x5F56E34B, 0xAC982AAC, 0x4AFE9FD9 };


//*****************************************************************
//         Set of init, input, and output functions below
//         to incrementally compute FNV512
//*****************************************************************

/* initialize context  (64-bit)
 ******************************************************************/
int FNV512init ( FNV512context * const ctx ) {
    int i;

    if ( !ctx )
        return fnvNull;
    for ( i=0; i<FNV512size/4; ++i )
        ctx->Hash[i] = FNV512basis[i];
    ctx->Computed = FNVinited+FNV512state;
    return fnvSuccess;
}   /* end FNV512init */

/* initialize context with a provided 64-byte vector basis  (64-bit)
 ******************************************************************/
int FNV512initBasis ( FNV512context * const ctx,
                      const uint8_t basis[FNV512size] ) {
    int      i;
    const uint8_t  *ui8p;

    if ( !ctx )
        return fnvNull;
    ui8p = basis + (FNV512size/4 - 1);
    for ( i=0; i < FNV512size/4; ++i ) {
        uint32_t  temp = (*ui8p--)<<8;
        temp = (temp + *ui8p--)<<8;
        temp = (temp + *ui8p--)<<8;
        ctx->Hash[i] = temp +  *ui8p;
        }
    ctx->Computed = FNVinited+FNV512state;
    return fnvSuccess;
}   /* end FNV512initBasis */

/* hash in a counted block  (64-bit)
 ******************************************************************/
int FNV512blockin ( FNV512context * const ctx,
                    const void *vin,
                    long int length ) {
    const uint8_t *in = (const uint8_t*)vin;
    uint64_t    temp[FNV512size/4];
    uint64_t    temp2[6];
    int         i;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV512state:
            ctx->Computed = FNVcomputed+FNV512state;
            break;
        case FNVcomputed+FNV512state:
            break;
        default:
            return fnvStateError;
        }
    if ( length < 0 )
        return fnvBadParam;
    for ( i=0; i<FNV512size/4; ++i )
         temp[i] = ctx->Hash[i];  // copy into temp
    for ( ; length > 0; length-- ) {
        /* temp = FNV512prime * ( temp ^ *in++ ); */
        temp[FNV512size/4-1] ^= *in++;
        for ( i=0; i<6; ++i )
            temp2[5-i] = temp[FNV512size/4-1-i] << FNV512shift;
        for ( i=0; i<FNV512size/4; ++i )
            temp[i] *= FNV512primeX;
        for ( i=0; i<6; ++i )
            temp[i] += temp2[i];
        for ( i=FNV512size/4-1; i>0; --i ) {
            temp[i-1] += temp[i] >> 32; // propagate carries
            temp[i] &= 0xFFFFFFFF;
            }
       }   /* end for length */
    for ( i=0; i<FNV512size/4; ++i )
        ctx->Hash[i] = (uint32_t)temp[i];  // store back into hash
    return fnvSuccess;
}   /* end FNV512blockin */

/* hash in a zero-terminated string not including the zero  (64-bit)
 ******************************************************************/
int FNV512stringin ( FNV512context * const ctx, const char *in ) {
    uint64_t   temp[FNV512size/4];
    uint64_t   temp2[6];
    int        i;
    uint8_t    ch;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV512state:
            ctx->Computed = FNVcomputed+FNV512state;
            break;
        case FNVcomputed+FNV512state:
            break;
        default:
             return fnvStateError;
         }
    for ( i=0; i<FNV512size/4; ++i )
         temp[i] = ctx->Hash[i];  // copy into temp
    while ( (ch = (uint8_t)*in++) ) {
        /* temp = FNV512prime * ( temp ^ ch ); */
        temp[FNV512size/4-1] ^= ch;
        for ( i=0; i<6; ++i )
            temp2[5-i] = temp[FNV512size/4-1-i] << FNV512shift;
        for ( i=0; i<FNV512size/4; ++i )
            temp[i] *= FNV512primeX;
        for ( i=0; i<6; ++i )
            temp[i] += temp2[i];
        for ( i=FNV512size/4-1; i>0; --i ) {
            temp[i-1] += temp[i] >> 32; // propagate carries
            temp[i] &= 0xFFFFFFFF;
            }
       }
    for ( i=0; i<FNV512size/4; ++i )
        ctx->Hash[i] = (uint32_t)temp[i];  // store back into hash
    return fnvSuccess;
}   /* end FNV512stringin */

/* return hash  (64-bit)
 ******************************************************************/
int FNV512result ( FNV512context * const ctx,
                   uint8_t out[FNV512size] ) {
    int i;

    if ( !ctx || !out )
        return fnvNull;
    if ( ctx->Computed != FNVcomputed+FNV512state )
        return fnvStateError;
    for ( i=0; i<FNV512size/4; ++i ) {
        out[4*i] = ctx->Hash[i] >> 24;
        out[4*i+1] = ctx->Hash[i] >> 16;
        out[4*i+2] = ctx->Hash[i] >> 8;
        out[4*i+3] = ctx->Hash[i];
        ctx -> Hash[i] = 0;
        }
    ctx->Computed = FNVemptied+FNV512state;
    return fnvSuccess;
}   /* end FNV512result */

//*****************************************************************
//        END VERSION FOR WHEN YOU HAVE 64-BIT ARITHMETIC
//*****************************************************************
#else    /*  FNV_64bitIntegers */
//*****************************************************************
//      START VERSION FOR WHEN YOU ONLY HAVE 32-BIT ARITHMETIC
//*****************************************************************

/*
  512-bit FNV_prime = 2^344 + 2^8 + 0x57 =
   0x00000000 00000000 00000000 00000000
     00000000 01000000 00000000 00000000
     00000000 00000000 00000000 00000000
     00000000 00000000 00000000 00000157 */
#define FNV512primeX 0x0157
#define FNV512shift 8

/* 0xB86DB0B1 171F4416 DCA1E50F 309990AC
     AC87D059 C9000000 00000000 00000D21
     E948F68A 34C192F6 2EA79BC9 42DBE7CE
     18203641 5F56E34B AC982AAC 4AFE9FD9 */

uint16_t FNV512basis[FNV512size/2] = {
     0xB86D, 0xB0B1, 0x171F, 0x4416, 0xDCA1, 0xE50F, 0x3099, 0x90AC,
     0xAC87, 0xD059, 0xC900, 0x0000, 0x0000, 0x0000, 0x0000, 0x0D21,
     0xE948, 0xF68A, 0x34C1, 0x92F6, 0x2EA7, 0x9BC9, 0x42DB, 0xE7CE,
     0x1820, 0x3641, 0x5F56, 0xE34B, 0xAC98, 0x2AAC, 0x4AFE, 0x9FD9
     };


//*****************************************************************
//         Set of init, input, and output functions below
//         to incrementally compute FNV512
//*****************************************************************

/* initialize context  (32-bit)
 ******************************************************************/
int FNV512init ( FNV512context * const ctx ) {
    int     i;

    if ( !ctx )
        return fnvNull;
    for ( i=0; i<FNV512size/2; ++i )
        ctx->Hash[i] = FNV512basis[i];
    ctx->Computed = FNVinited+FNV512state;
    return fnvSuccess;
}   /* end FNV512init */

/* initialize context with a provided 64-byte vector basis  (32-bit)
 ******************************************************************/
int FNV512initBasis ( FNV512context * const ctx,
                      const uint8_t basis[FNV512size] ) {
    int      i;
    const uint8_t  *ui8p;

    if ( !ctx )
        return fnvNull;
    ui8p = basis + ( FNV512size/2 - 1 );
    for ( i=0; i < FNV512size/2; ++i ) {
        uint32_t temp = *ui8p--;
        ctx->Hash[i] = ( temp<<8 ) + (*ui8p--);
        }
    ctx->Computed = FNVinited+FNV512state;
    return fnvSuccess;
}   /* end FNV512initBasis */

/* hash in a counted block  (32-bit)
 ******************************************************************/
int FNV512blockin ( FNV512context * const ctx,
                    const void *vin,
                    long int length ) {
    const uint8_t *in = (const uint8_t*)vin;
    uint32_t   temp[FNV512size/2];
    uint32_t   temp2[11];
    int        i;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV512state:
            ctx->Computed = FNVcomputed+FNV512state;
            break;
        case FNVcomputed+FNV512state:
            break;
        default:
            return fnvStateError;
        }
    if ( length < 0 )
        return fnvBadParam;
    for ( i=0; i<FNV512size/2; ++i )
        temp[i] = ctx->Hash[i];  // copy into temp
    for ( ; length > 0; length-- ) {
        /* temp = FNV512prime * ( temp ^ *in++ ); */
        temp[FNV512size/2-1] ^= *in++;
        for ( i=0; i<11; ++i )
            temp2[10-i] = temp[FNV512size/2-1-i] << FNV512shift;
        for ( i=0; i<FNV512size/2; ++i )
            temp[i] *= FNV512primeX;
        for ( i=0; i<11; ++i )
            temp[i] += temp2[i];
        for ( i=FNV512size/2-1; i>0; --i ) {
            temp[i-1] += temp[i] >> 16; // propagate carries
            temp[i] &= 0xFFFF;
            }
        }   /* end for length */
    for ( i=0; i<FNV512size/2; ++i )
        ctx->Hash[i] = (uint16_t)temp[i];  // store back into hash
    return fnvSuccess;
}   /* end FNV512blockin */

/* hash in a zero-terminated string not including the zero  (32-bit)
 ******************************************************************/
int FNV512stringin ( FNV512context * const ctx, const char *in ) {
    uint32_t   temp[FNV512size/2];
    uint32_t   temp2[11];
    int        i;
    uint8_t    ch;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV512state:
            ctx->Computed = FNVcomputed+FNV512state;
            break;
        case FNVcomputed+FNV512state:
            break;
        default:
             return fnvStateError;
         }
    for ( i=0; i<FNV512size/2; ++i )
         temp[i] = ctx->Hash[i];  // copy into temp
    while ( (ch = (uint8_t)*in++) ) {
        /* temp = FNV512prime * ( temp ^ *in++ ); */
        temp[FNV512size/2-1] ^= ch;
        for ( i=0; i<11; ++i )
            temp2[10-i] = temp[FNV512size/2-1-i] << FNV512shift;
        for ( i=0; i<FNV512size/2; ++i )
            temp[i] *= FNV512primeX;
        for ( i=0; i<11; ++i )
            temp[i] += temp2[i];
        for ( i=FNV512size/2-1; i>0; --i ) {
            temp[i-1] += temp[i] >> 16; // propagate carries
            temp[i] &= 0xFFFF;
            }
         }
    for ( i=0; i<FNV512size/2; ++i )
        ctx->Hash[i] = temp[i];  // store back into hash
    return fnvSuccess;
}   /* end FNV512stringin */

/* return hash  (32-bit)
 ******************************************************************/
int FNV512result ( FNV512context * const ctx,
                   uint8_t out[FNV512size] ) {
    int    i;

    if ( !ctx || !out )
        return fnvNull;
    if ( ctx->Computed != FNVcomputed+FNV512state )
        return fnvStateError;
    for ( i=0; i<FNV512size/2; ++i ) {
        out[2*i] = ctx->Hash[i] >> 8;
        out[2*i+1] = ctx->Hash[i];
        ctx->Hash[i] = 0;
        }
    ctx->Computed = FNVemptied+FNV512state;
    return fnvSuccess;
}   /* end FNV512result */

#endif    /*  FNV_64bitIntegers */
//*****************************************************************
//        END VERSION FOR WHEN YOU ONLY HAVE 32-BIT ARITHMETIC
//*****************************************************************

<CODE ENDS>

6.2.6. FNV1024 Code

The header and C source for 1024-bit FNV-1a providing a byte vector hash.

<CODE BEGINS> file "FNV1024.h"


//*********************** FNV1024.h ***********************//
//************* See RFC NNNN for details. *****************//
/* Copyright (c) 2016, 2024 IETF Trust and the persons
 * identified as authors of the code.  All rights reserved.
 * See fnv-private.h for terms of use and redistribution.
 */

#ifndef _FNV1024_H_
#define _FNV1024_H_

/*
 *  Description:
 *      This file provides headers for the 1024-bit version of
 *      the FNV-1a non-cryptographic hash algorithm.
 */

#include "FNVconfig.h"
#include "FNVErrorCodes.h"

#include <stdint.h>
#define FNV1024size (1024/8)

/* If you do not have the ISO standard stdint.h header file, then
 * you must typedef the following types:
 *
 *    type              meaning
 *  uint64_t    unsigned 64-bit integer (ifdef FNV_64bitIntegers)
 *  uint32_t    unsigned 32-bit integer
 *  uint16_t    unsigned 16-bit integer
 *  uint8_t     unsigned 8-bit integer (i.e., unsigned char)
 */

/*
 *  This structure holds context information for an FNV1024 hash
 */
#ifdef FNV_64bitIntegers
    /* version if 64-bit integers supported */
typedef struct FNV1024context_s {
        int Computed;  /* state */
        uint32_t Hash[FNV1024size/4];
} FNV1024context;

#else
    /* version if 64-bit integers NOT supported */

typedef struct FNV1024context_s {
        int Computed;  /* state */
        uint16_t Hash[FNV1024size/2];
} FNV1024context;

#endif /* FNV_64bitIntegers */

/*
 *  Function Prototypes:
 *
 *    FNV1024string: hash a zero-terminated string not including
 *                   the terminating zero
 *    FNV1024block: hash a specified length byte vector
 *    FNV1024file: hash the contents of a file
 *
 *    FNV1024init: initializes an FNV1024 context
 *    FNV1024initBasis: initializes an FNV1024 context with a
 *                      provided 128-byte vector basis
 *    FNV1024blockin: hash in a specified length byte vector
 *    FNV1024stringin: hash in a zero-terminated string not
 *                     including the terminating zero
 *    FNV1024result: returns the hash value
 *
 *    Hash is returned as an array of 8-bit unsigned integers
 */

#ifdef __cplusplus
extern "C" {
#endif

/* FNV1024 */
extern int FNV1024string ( const char *in,
                           uint8_t out[FNV1024size] );
extern int FNV1024block ( const void *vin,
                          long int length,
                          uint8_t out[FNV1024size] );
extern int FNV1024file ( const char *fname,
                         uint8_t out[FNV1024size] );
extern int FNV1024init ( FNV1024context * const );
extern int FNV1024initBasis ( FNV1024context * const,
                              const uint8_t basis[FNV1024size] );
extern int FNV1024blockin ( FNV1024context * const,
                            const void *vin,
                            long int length );
extern int FNV1024stringin ( FNV1024context * const,
                            const char *in );
extern int FNV1024result ( FNV1024context * const,
                           uint8_t out[FNV1024size] );

#ifdef __cplusplus
}
#endif

#endif /* _FNV1024_H_ */

<CODE ENDS>
<CODE BEGINS> file "FNV1024.c"


//************************** FNV1024.c **************************//
//****************** See RFC NNNN for details *******************//
/* Copyright (c) 2016, 2024 IETF Trust and the persons
 * identified as authors of the code.  All rights reserved.
 * See fnv-private.h for terms of use and redistribution.
 */

/* This file implements the FNV (Fowler, Noll, Vo) non-cryptographic
 * hash function FNV-1a for 1024-bit hashes.
 */

#include <stdio.h>

#include "fnv-private.h"
#include "FNV1024.h"

//*****************************************************************
//  COMMON CODE FOR 64- AND 32-BIT INTEGER MODES
//*****************************************************************

/* FNV1024 hash a zero-terminated string not including the zero
 ******************************************************************/
int FNV1024string ( const char *in, uint8_t out[FNV1024size] ) {
    FNV1024context    ctx;
    int              err;

    if ( (err = FNV1024init ( &ctx )) != fnvSuccess)
        return err;
    if ( (err = FNV1024stringin ( &ctx, in )) != fnvSuccess)
        return err;
    return FNV1024result ( &ctx, out );
}   /* end FNV1024string */

/* FNV1024 hash a counted block  (64/32-bit)
 ******************************************************************/
int FNV1024block ( const void *vin,
                  long int length,
                  uint8_t out[FNV1024size] ) {
    FNV1024context   ctx;
    int              err;

    if ( (err = FNV1024init ( &ctx )) != fnvSuccess)
        return err;
    if ( (err = FNV1024blockin ( &ctx, vin, length)) != fnvSuccess)
        return err;
    return FNV1024result ( &ctx, out );
}   /* end FNV1024block */


/* hash the contents of a file
 ******************************************************************/
int FNV1024file ( const char *fname,
                        uint8_t out[FNV1024size] ) {
    FILE *fp;
    long int i;
    char buf[1024];
    FNV1024context e1024Context;
    int error;

    if ( !fname || !out )
        return fnvNull;
    if ( ( fp = fopen ( fname, "rb") ) == NULL )
        return fnvBadParam;
    if ( (error = FNV1024init (&e1024Context)) ) {
        fclose(fp);
        return error;
    }
    if ( (error = FNV1024blockin ( &e1024Context, "", 0)) ) {
        fclose(fp);
        return error;
    }
    while ( ( i = fread ( buf, 1, sizeof(buf), fp ) ) > 0 )
        if ( (error = FNV1024blockin ( &e1024Context, buf, i)) ) {
            fclose(fp);
            return error;
        }
    error = ferror(fp);
    fclose(fp);
    if (error)
        return fnvBadParam;
    return FNV1024result ( &e1024Context, out );
}   /* end FNV1024file */

//****************************************************************//
// START VERSION FOR WHEN YOU HAVE 64-BIT ARITHMETIC
//****************************************************************//
#ifdef FNV_64bitIntegers

/*
 1024-bit FNV_prime = 2^680 + 2^8 + 0x8d =
   0x0000000000000000 0000000000000000
     0000000000000000 0000000000000000
     0000000000000000 0000010000000000
     0000000000000000 0000000000000000
     0000000000000000 0000000000000000
     0000000000000000 0000000000000000
     0000000000000000 0000000000000000
     0000000000000000 000000000000018D */
#define FNV1024primeX 0x018D
#define FNV1024shift 8

/* 0x0000000000000000 005F7A76758ECC4D
     32E56D5A591028B7 4B29FC4223FDADA1
     6C3BF34EDA3674DA 9A21D90000000000
     0000000000000000 0000000000000000
     0000000000000000 0000000000000000
     0000000000000000 000000000004C6D7
     EB6E73802734510A 555F256CC005AE55
     6BDE8CC9C6A93B21 AFF4B16C71EE90B3 */

uint32_t FNV1024basis[FNV1024size/4] = {
  0x00000000, 0x00000000, 0x005F7A76, 0x758ECC4D,
  0x32E56D5A, 0x591028B7, 0x4B29FC42, 0x23FDADA1,
  0x6C3BF34E, 0xDA3674DA, 0x9A21D900, 0x00000000,
  0x00000000, 0x00000000, 0x00000000, 0x00000000,
  0x00000000, 0x00000000, 0x00000000, 0x00000000,
  0x00000000, 0x00000000, 0x00000000, 0x0004C6D7,
  0xEB6E7380, 0x2734510A, 0x555F256C, 0xC005AE55,
  0x6BDE8CC9, 0xC6A93B21, 0xAFF4B16C, 0x71EE90B3
 };


//***************************************************************//
//         Set of init, input, and output functions below
//         to incrementally compute FNV1024
//**************************************************************//

/* initialize context  (64-bit)
 ******************************************************************/
int FNV1024init ( FNV1024context * const ctx ) {
    int i;

    if ( !ctx )
        return fnvNull;
    for ( i=0; i<FNV1024size/4; ++i )
        ctx->Hash[i] = FNV1024basis[i];
    ctx->Computed = FNVinited+FNV1024state;
    return fnvSuccess;
}   /* end FNV1024init */

/* initialize context with a provided 128-byte vector basis  (64-bit)
 ******************************************************************/
int FNV1024initBasis ( FNV1024context * const ctx,
                       const uint8_t basis[FNV1024size] ) {
    int            i;
    const uint8_t  *ui8p;

    if ( !ctx )
        return fnvNull;
    ui8p = basis + (FNV1024size/4 - 1);
    for ( i=0; i < FNV1024size/4; ++i ) {
            uint32_t temp = (*ui8p--)<<8;
            temp = (temp + *ui8p--)<<8;
            temp = (temp + *ui8p--)<<8;
            ctx->Hash[i] = temp +  *ui8p;
        }
    ctx->Computed = FNVinited+FNV1024state;
    return fnvSuccess;
}   /* end FNV1024initBasis */

/* hash in a counted block  (64-bit)
 ******************************************************************/
int FNV1024blockin ( FNV1024context * const ctx,
                    const void *vin,
                    long int length ) {
    const uint8_t *in = (const uint8_t*)vin;
    uint64_t    temp[FNV1024size/4];
    uint64_t    temp2[11];
    int         i;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV1024state:
            ctx->Computed = FNVcomputed+FNV1024state;
            break;
        case FNVcomputed+FNV1024state:
            break;
        default:
            return fnvStateError;
        }
    if ( length < 0 )
        return fnvBadParam;
    for ( i=0; i<FNV1024size/4; ++i )
         temp[i] = ctx->Hash[i];  // copy into temp
    for ( ; length > 0; length-- ) {
        /* temp = FNV1024prime * ( temp ^ *in++ ); */
        temp[FNV1024size/4-1] ^= *in++;
        for ( i=0; i<11; ++i )
            temp2[10-i] = temp[FNV1024size/4-1-i] << FNV1024shift;
        for ( i=0; i<FNV1024size/4; ++i )
            temp[i] *= FNV1024primeX;
        for ( i=0; i<11; ++i )
            temp[i] += temp2[i];
        for ( i=FNV1024size/4-1; i>0; --i ) {
            temp[i-1] += temp[i] >> 32;  // propagate carries
            temp[i] &= 0xFFFFFFFF;
            }
       }   /* end for length */
    for ( i=0; i<FNV1024size/4; ++i )
        ctx->Hash[i] = (uint32_t)temp[i];  // store back into hash
    return fnvSuccess;
}   /* end FNV1024blockin */

/* hash in a zero-terminated string not including the zero  (64-bit)
 ******************************************************************/
int FNV1024stringin ( FNV1024context * const ctx, const char *in ) {
    uint64_t   temp[FNV1024size/4];
    uint64_t   temp2[11];
    int        i;
    uint8_t    ch;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV1024state:
            ctx->Computed = FNVcomputed+FNV1024state;
            break;
        case FNVcomputed+FNV1024state:
            break;
        default:
             return fnvStateError;
         }
    for ( i=0; i<FNV1024size/4; ++i )
         temp[i] = ctx->Hash[i];  // copy into temp
    while ( (ch = (uint8_t)*in++) ) {
        /* temp = FNV1024prime * ( temp ^ ch ); */
        temp[FNV1024size/4-1] ^= ch;
        for ( i=0; i<11; ++i )
            temp2[10-i] = temp[FNV1024size/4-1-i] << FNV1024shift;
        for ( i=0; i<FNV1024size/4; ++i )
            temp[i] *= FNV1024primeX;
        for ( i=0; i<11; ++i )
                temp[i] += temp2[i];
        for ( i=FNV1024size/4-1; i>0; --i ) {
            temp[i-1] += temp[i] >> 32;
            temp[i] &= 0xFFFFFFFF;
            }
       }
    for ( i=0; i<FNV1024size/4; ++i )
        ctx->Hash[i] = (uint32_t)temp[i];  // store back into hash
    return fnvSuccess;
}   /* end FNV1024stringin */

/* return hash  (64-bit)
 ******************************************************************/
int FNV1024result ( FNV1024context * const ctx,
                    uint8_t out[FNV1024size] ) {
    int i;

    if ( !ctx || !out )
        return fnvNull;
    if ( ctx->Computed != FNVcomputed+FNV1024state )
        return fnvStateError;
    for ( i=0; i<FNV1024size/4; ++i ) {
        out[4*i] = ctx->Hash[i] >> 24;
        out[4*i+1] = ctx->Hash[i] >> 16;
        out[4*i+2] = ctx->Hash[i] >> 8;
        out[4*i+3] = ctx->Hash[i];
        ctx -> Hash[i] = 0;
        }
    ctx->Computed = FNVemptied+FNV1024state;
    return fnvSuccess;
}   /* end FNV1024result */

//****************************************************************//
//        END VERSION FOR WHEN YOU HAVE 64-BIT ARITHMETIC
//***************************************************************//
#else    /*  FNV_64bitIntegers */
//***************************************************************//
//      START VERSION FOR WHEN YOU ONLY HAVE 32-BIT ARITHMETIC
//***************************************************************//

/* version for when you only have 32-bit arithmetic
 ******************************************************************/

/*
 1024-bit FNV_prime = 2^680 + 2^8 + 0x8d =
   0x00000000 00000000 00000000 00000000
     00000000 00000000 00000000 00000000
     00000000 00000000 00000100 00000000
     00000000 00000000 00000000 00000000
     00000000 00000000 00000000 00000000
     00000000 00000000 00000000 00000000
     00000000 00000000 00000000 00000000
     00000000 00000000 00000000 0000018D */
#define FNV1024primeX 0x018D
#define FNV1024shift 8

/* 0x00000000 00000000 005F7A767 58ECC4D
     32E56D5A 591028B7 4B29FC42 23FDADA1
     6C3BF34E DA3674DA 9A21D900 00000000
     00000000 00000000 00000000 00000000
     00000000 00000000 00000000 00000000
     00000000 00000000 00000000 0004C6D7
     EB6E7380 2734510A 555F256C C005AE55
     6BDE8CC9 C6A93B21 AFF4B16C 71EE90B3 */

uint16_t FNV1024basis[FNV1024size/2] = {
  0x0000, 0x0000, 0x0000, 0x0000, 0x005F, 0x7A76, 0x758E, 0xCC4D,
  0x32E5, 0x6D5A, 0x5910, 0x28B7, 0x4B29, 0xFC42, 0x23FD, 0xADA1,
  0x6C3B, 0xF34E, 0xDA36, 0x74DA, 0x9A21, 0xD900, 0x0000, 0x0000,
  0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
  0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,
  0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0004, 0xC6D7,
  0xEB6E, 0x7380, 0x2734, 0x510A, 0x555F, 0x256C, 0xC005, 0xAE55,
  0x6BDE, 0x8CC9, 0xC6A9, 0x3B21, 0xAFF4, 0xB16C, 0x71EE, 0x90B3
};


//*****************************************************************
//         Set of init, input, and output functions below
//         to incrementally compute FNV1024
//*****************************************************************

/* initialize context  (32-bit)
 ******************************************************************/
int FNV1024init ( FNV1024context * const ctx ) {
    int     i;

    if ( !ctx )
        return fnvNull;
    for ( i=0; i<FNV1024size/2; ++i )
        ctx->Hash[i] = FNV1024basis[i];
    ctx->Computed = FNVinited+FNV1024state;
    return fnvSuccess;
}   /* end FNV1024init */

/* initialize context with a provided 128-byte vector basis  (32-bit)
 ******************************************************************/
int FNV1024initBasis ( FNV1024context * const ctx,
                       const uint8_t basis[FNV1024size] ) {
    int      i;
    const uint8_t  *ui8p;

    if ( !ctx )
        return fnvNull;
    ui8p = basis + ( FNV1024size/2 - 1 );
    for ( i=0; i < FNV1024size/2; ++i ) {
        uint32_t temp = *ui8p--;
        ctx->Hash[i] = ( temp<<8 ) + (*ui8p--);
        }
    ctx->Computed = FNVinited+FNV1024state;
    return fnvSuccess;
}   /* end FNV1024initBasis */

/* hash in a counted block  (32-bit)
 ******************************************************************/
int FNV1024blockin ( FNV1024context * const ctx,
                    const void *vin,
                    long int length ) {
    const uint8_t *in = (const uint8_t*)vin;
    uint32_t   temp[FNV1024size/2];
    uint32_t   temp2[22];
    int        i;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV1024state:
            ctx->Computed = FNVcomputed+FNV1024state;
            break;
        case FNVcomputed+FNV1024state:
            break;
        default:
            return fnvStateError;
        }
    if ( length < 0 )
        return fnvBadParam;
    for ( i=0; i<FNV1024size/2; ++i )
        temp[i] = ctx->Hash[i];  // copy into temp
    for ( ; length > 0; length-- ) {
        /* temp = FNV1024prime * ( temp ^ *in++ ); */
        temp[FNV1024size/2-1] ^= *in++;
        for ( i=0; i<22; ++i )
            temp2[21-i] = temp[FNV1024size/2-1-i] << FNV1024shift;
        for ( i=0; i<FNV1024size/2; ++i )
            temp[i] *= FNV1024primeX;
        for ( i=0; i<22; ++i )
            temp[i] += temp2[i];
        for ( i=FNV1024size/2-1; i>0; --i ) {
            temp[i-1] += temp[i] >> 16; // propagate carries
            temp[i] &= 0xFFFF;
            }
        }
    for ( i=0; i<FNV1024size/2; ++i )
        ctx->Hash[i] = temp[i];  // store back into hash
    return fnvSuccess;
}   /* end FNV1024blockin */

/* hash in a zero-terminated string not including the zero  (32-bit)
 ******************************************************************/
int FNV1024stringin ( FNV1024context * const ctx, const char *in ) {
    uint32_t   temp[FNV1024size/2];
    uint32_t   temp2[22];
    int        i;
    uint8_t    ch;

    if ( !ctx || !in )
        return fnvNull;
    switch ( ctx->Computed ) {
        case FNVinited+FNV1024state:
            ctx->Computed = FNVcomputed+FNV1024state;
            break;
        case FNVcomputed+FNV1024state:
            break;
        default:
             return fnvStateError;
         }
    for ( i=0; i<FNV1024size/2; ++i )
         temp[i] = ctx->Hash[i];  // copy into temp
    while ( (ch = (uint8_t)*in++) ) {
        /* temp = FNV1024prime * ( temp ^ *in++ ); */
        temp[FNV1024size/2-1] ^= ch;
        for ( i=0; i<22; ++i )
            temp2[21-i] = temp[FNV1024size/2-1-i] << FNV1024shift;
        for ( i=0; i<FNV1024size/2; ++i )
            temp[i] *= FNV1024primeX;
        for ( i=0; i<22; ++i )
             temp[i] += temp2[i];
        for ( i=FNV1024size/2-1; i>0; --i ) {
            temp[i-1] += temp[i] >> 16; // propagate carries
            temp[i] &= 0xFFFF;
            }
         }
    for ( i=0; i<FNV1024size/2; ++i )
        ctx->Hash[i] = temp[i];  // store back into hash
    return fnvSuccess;
}   /* end FNV1024stringin */

/* return hash  (32-bit)
 ******************************************************************/
int FNV1024result ( FNV1024context * const ctx,
                    uint8_t out[FNV1024size] ) {
    int    i;

    if ( !ctx || !out )
        return fnvNull;
    if ( ctx->Computed != FNVcomputed+FNV1024state )
        return fnvStateError;
    for ( i=0; i<FNV1024size/2; ++i ) {
        out[2*i] = ctx->Hash[i] >> 8;
        out[2*i+1] = ctx->Hash[i];
        ctx->Hash[i] = 0;
        }
    ctx->Computed = FNVemptied+FNV1024state;
    return fnvSuccess;
}   /* end FNV1024result */

#endif    /*  FNV_64bitIntegers */
//****************************************************************//
//        END VERSION FOR WHEN YOU ONLY HAVE 32-BIT ARITHMETIC
//****************************************************************//

<CODE ENDS>

6.3. FNV Test Code

Below is source code for a test driver with a command line interface documented in Section 6.1.3. By default, with no command line arugments, it runs tests of all FNV lengths.

<CODE BEGINS> file "main.c"


//************************* Main.c **************************//
//*************** See RFC NNNN for details. *****************//
/* Copyright (c) 2016, 2024 IETF Trust and the persons
 * identified as authors of the code.  All rights reserved.
 * See fnv-private.h for terms of use and redistribution.
 */

#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <unistd.h>
#include <errno.h>

/* To do a thorough test you need to run with
 * FNV_64bitIntegers defined and with it undefined
 */
#include "FNVconfig.h"

#include "fnv-private.h"
#include "FNV32.h"
#include "FNV64.h"
#include "FNV128.h"
#include "FNV256.h"
#include "FNV512.h"
#include "FNV1024.h"

/* global variables */
char    *funcName = "funcName not set?";
char    *errteststring = "foo";
int     Terr = -1; /* Total errors */
int     verbose = 0; /* verbose flag */
enum { FNV32selected = 0, FNV64selected, FNV128selected,
       FNV256selected, FNV512selected, FNV1024selected,
       FNVnone = -1 } selected = FNVnone;
#define NTestBytes 3
uint8_t errtestbytes[NTestBytes] = { (uint8_t)1,
    (uint8_t)2, (uint8_t)3 };
char    *teststring[] = {
        "",
        "a",
        "foobar",
        "Hello!\x01\xFF\xED"
};
#define NTstrings (sizeof(teststring)/sizeof(char *))

FNV32context    e32Context;
uint32_t        eUint32 = 42;
#ifdef FNV_64bitIntegers
uint64_t        eUint64 = 42;
#endif
FNV64context    e64Context;
FNV128context   e128Context;
FNV256context   e256Context;
FNV512context   e512Context;
FNV1024context  e1024Context;
uint8_t hash[FNV1024size];  /* largest size needed */
char             tempFileNameTemplate[] = "tmp.XXXXXXXXXX";
const char      *tempFileName = 0;


//****************************************************************
// local prototypes in alphabetic order
//****************************************************************
void CommonTest ( void );
void ErrTestReport ( void );
int find_selected(const char *optarg);
void HexPrint ( int count, const uint8_t *ptr );
void TestAll ( void );
void Test32 ( void );
void Test64 ( void );
void Test128 ( void );
void Test256 ( void );
void Test512 ( void );
void Test1024 ( void );
void TestNValue ( const char *subfunc,  // test calculated value
                  const char *string,
                  int N,  // size
                  const uint8_t *was,
                  const uint8_t should[N] );
int TestR ( const char *,
            int expect,
            int actual ); // test return code
void usage( const char *argv0 ); // print help message
void ValueTestReport ( void );      // print test results

#ifndef FNV_64bitIntegers
# undef uint64
# define uint64_t no_64_bit_integers
#endif /* FNV_64bitIntegers */

struct {    // indexed into by the enum variable "selected"
    int length;
    void (*Testfunc)( void );
    int (*Stringfunc)( const char *, uint8_t *);
    int (*Blockfunc)( const void *, long int, uint8_t *);
    int (*Filefunc)( const char *, uint8_t *);
} funcmap[] = {  // valid sizes
    { 32, Test32, FNV32string, FNV32block, FNV32file },
    { 64, Test64, FNV64string, FNV64block, FNV64file },
    { 128, Test128, FNV128string, FNV128block, FNV128file },
    { 256, Test256, FNV256string, FNV256block, FNV256file },
    { 512, Test512, FNV512string, FNV512block, FNV512file },
    { 1024, Test1024, FNV1024string, FNV1024block, FNV1024file },
    { 0, Test32, FNV32string, FNV32block }  // fence post
};


//****************************************************************
//  main
//****************************************************************
int main( int argc, const char **argv ) {
    int     i,
    option;  // command line option letter
    uint16_t    endianness = 5*256 + 11;

    mkstemp(tempFileNameTemplate);
    tempFileName = tempFileNameTemplate;

    if ( ((uint8_t *)&endianness)[0] != 11 )
        printf ("Coded for Little Endian but computer seems\n"
                " to be Big Endian! Multi-byte integer results\n"
                " may be incorrect!\n");
    if ( argc == 1 ) {  // if no arguments
        TestAll();
        if ( tempFileName )
            unlink(tempFileName);
        exit(0);
    }

// process command line options
// *****************************************************************
    while ((option = getopt(argc, (char *const *)argv, ":af:ht:u:v"))
           != -1) {
        if ( verbose )
            printf ( "Got option %c\n", option );
        switch ( option ) {
            case 'a':  // run all tests
                TestAll();
                break;
            case 'f':   // followed by name of file to hash
                if ( selected == FNVnone ) {
                    printf ( "No hash size selected.\n" );
                    break;
                }
                printf ( "FNV-%i Hash of contents of file '%s':\n",
                         funcmap[selected].length, optarg );
                switch ( selected ) {
                  case FNV32selected:
                      if (FNV32INTfile( optarg, &eUint32 )
                              == fnvSuccess)
                          HexPrint ( FNV32size,
                                     (uint8_t *)&eUint32 );
                      else
                          printf( "Hashing file '%s' fails: %s.\n",
                                   optarg, strerror(errno) );
                      break;
                  case FNV64selected:
#ifdef FNV_64bitIntegers
                      if (FNV64INTfile( optarg, &eUint64 )
                              == fnvSuccess)
                          HexPrint ( FNV64size,
                                     (uint8_t *)&eUint64 );
#else
                      if ( FNV64file(optarg, hash) == fnvSuccess)
                          HexPrint ( FNV64size, hash );
#endif
                      else
                          printf( "Hashing file '%s' fails: %s.\n",
                                   optarg, strerror(errno) );
                      break;
                  case FNV128selected:
                      if ( FNV128file( optarg, hash ) == fnvSuccess)
                          HexPrint ( FNV128size, hash );
                      else
                          printf( "Hashing file '%s' fails: %s.\n",
                                   optarg, strerror(errno) );
                      break;
                  case FNV256selected:
                      if ( FNV256file( optarg, hash ) == fnvSuccess)
                          HexPrint ( FNV256size, hash );
                      else
                          printf( "Hashing file '%s' fails: %s.\n",
                                   optarg, strerror(errno) );
                      break;
                  case FNV512selected:
                      if ( FNV512file( optarg, hash ) == fnvSuccess)
                          HexPrint ( FNV512size, hash );
                      else
                          printf( "Hashing file '%s' fails: %s.\n",
                                   optarg, strerror(errno) );
                      break;
                  case FNV1024selected:
                      if ( FNV1024file( optarg, hash ) == fnvSuccess)
                          HexPrint ( FNV1024size, hash );
                      else
                          printf( "Hashing file '%s' fails: %s.\n",
                                  optarg, strerror(errno) );
                    break;
                  default:
                    return 1;  // internal error
                }  // end switch funcmap[selected].length
                printf ( "\n" );
                break;
            case 'h':   // help
                usage( argv[0] );
                break;
            case 't':   // follow by size of FNV to test, 0->all
                selected = find_selected(optarg);
                if (selected == FNVnone)
                    printf ( "Bad argument to option -t\n"
                             "Valid sizes are 32, 64, 128,"
                             " 256, 512, and 1024\n");
                else
                    funcmap[selected].Testfunc();   // invoke test
                break;
            case 'u':   // follow by size of FNV to use
                selected = find_selected(optarg);
                if ( selected == FNVnone )
                    printf ( "Bad argument to option -u\n"
                             "Valid sizes are 32, 64, 128,"
                             "256, 512, and 1024\n" );
                break;
            case 'v':   // toggle Verbose flag
                if ( (verbose ^= 1) ) {
                    printf ( "Verbose on.\n" );
#ifdef FNV_64bitIntegers
                    printf ("Has 64-bit Integers. ");
#else
                    printf ("Does not have 64-bit integers. ");
#endif
                    // also tests the TestR function
                    funcName = "Testing TestR";
                    TestR ( "should fail", 1, 2 );
                    TestR ( "should not have failed", 3, 3 );
                }
                else
                    printf ( "Verbose off.\n" );
                break;
            case '?':   //
                printf ( "Unknown option %c\n", optopt );
                usage( argv[0] );
                return 1;
        }  /* end switch */
    }  /* end while */
    if ( ( option == -1 ) && verbose )
        printf ( "No more options.\n" );

// Through all the options, now, if a size is set, encrypt any
//   other tokens on the command line
//******************************************************
    for ( i = optind; i < argc; ++i ) {
        int     rc; // return code

        if ( selected == FNVnone ) {
            printf ( "No hash size selected.\n" );
            break;  // out of for
        }
        rc = funcmap[selected].Stringfunc(argv[i], hash);
        if ( rc )
            printf ( "FNV-%i of '%s' returns error %i\n",
                    funcmap[selected].length,
                    argv[i], rc );
        else {
            printf ( "FNV-%i of '%s' is ",
                    funcmap[selected].length, argv[i] );
            HexPrint ( funcmap[selected].length/8, hash );
            printf ( "\n" );
        }
    }
    if ( tempFileName )
        unlink(tempFileName);
    return 0;
}     /* end main */

/* Write to a temp file
 ******************************************************************/
const char *WriteTemp( const char *str, long int iLen ) {
    FILE *fp = fopen( tempFileName, "w" );
    if (!fp) {
        printf( "Cannot open tempfile: %s: %s\n",
                tempFileName, strerror(errno) );
        return 0;
    }
    long int ret = fwrite( str, 1, iLen, fp );
    fclose(fp);
    if ( ret != iLen ) {
        printf( "Cannot open tempfile: %s: %s\n",
                tempFileName, strerror(errno) );
        return 0;
    }
    return tempFileName;
}

//****************************************************************
//  Test status return code
//****************************************************************
int TestR ( const char *name, int expect, int actual ) {
    if ( expect != actual ) {
        printf ( "%s %s returned %i instead of %i.\n",
                 funcName, name, actual, expect );
        ++Terr;  /* increment  error count */
        }
    return actual;
}    /* end TestR */

//****************************************************************
//  General byte vector return value test
//****************************************************************
void TestNValue ( const char *subfunc,
                  const char *string,
                  int N,
                  const uint8_t was[N],
                  const uint8_t should[N] ) {
    if ( memcmp ( was, should, N) != 0 ) {
        ++Terr;
        printf ( "%s %s of '%s'",
                funcName, subfunc, string );
        printf ( " computed " );
        HexPrint ( N, was );
        printf ( ", expected " );
        HexPrint ( N, should );
        printf ( ".\n" );
    }
    else if ( verbose ) {
        printf ( "%s %s of '%s' computed ",
                funcName, subfunc, string );
        HexPrint ( N, was );
        printf ( " as expected.\n" );
    }
}   /* end TestNValue */

//****************************************************************
//  Report on status/value returns
//****************************************************************
void ErrTestReport ( void ) {
    if ( Terr )
        printf ( "%s test of error checks failed %i times.\n",
                funcName, Terr );
    else if ( verbose )
        printf ( "%s test of error checks passed.\n",
                funcName );
}  /* end ErrTestReport */

void ValueTestReport ( void ) {
    if ( Terr )
        printf ( "%s test of return values failed %i times.\n",
                funcName, Terr );
    else
        printf ( "%s test of return values passed.\n", funcName );
}  /* end ValueTestReport */

//****************************************************************
//  Verify the size of hash as a command line option argument
//    and return the index in funcmap[], -1 if not found.
//****************************************************************
int find_selected(const char *optarg) {
    int argval, count;

    count = sscanf ( optarg, "%i", &argval );
    if ( count > 0 ) {
      int i;
        for ( i = 0; funcmap[i].length; ++i ) {
            if ( funcmap[i].length == argval ) {
                return i;
            }  /* end if */
        }  /* end for */
    }
    return FNVnone;
}   /* end find_selected */

//****************************************************************
//  Print some bytes as hexadecimal
//****************************************************************
void HexPrint( int count, const uint8_t *ptr ) {
    int   i;

    for ( i = 0; i < count; ++i )
        printf ( "%02X", ptr[i] );
}   /* end HexPrint */

//****************************************************************
//  Test all sizes
//****************************************************************
void TestAll ( void ) {
    Test32();
    Test64();
    Test128();
    Test256();
    Test512();
    Test1024();
}   /* end TestAll */

//****************************************************************
//  Common error check tests
//****************************************************************
void CommonTest ( void ) {

    TestR ( "string1b", fnvNull,
        funcmap[selected].Stringfunc ( (char *)0, hash ) );
    TestR ( "string2b", fnvNull,
        funcmap[selected].Stringfunc ( errteststring,
                                      (uint8_t *)0 ) );
    TestR ( "block1b", fnvNull,
        funcmap[selected].Blockfunc ( (uint8_t *)0, 1, hash ) );
    TestR ( "block2b", fnvBadParam,
        funcmap[selected].Blockfunc ( errtestbytes, -1, hash ) );
    TestR ( "block3b", fnvNull,
        funcmap[selected].Blockfunc ( errtestbytes, 1,
                                     (uint8_t *)0 ) );
    TestR ( "file1", fnvNull,
        funcmap[selected].Filefunc ( (char *)0, hash ));
    TestR ( "file2", fnvNull,
        funcmap[selected].Filefunc ( "foo.txt", (uint8_t *)0 ));
}   /* end CommonTest */

//****************************************************************
//  Print command line help
//****************************************************************
void usage( const char *argv0 ) {
    printf (
        "%s [-a] [-t nnn] [-u nnn] [-v] [-f filename] [token ...]\n"
        "  -a = run all tests\n"
        "  -f filename = hash file contents\n"
        "  -h = help, print this message\n"
        "  -t nnn = Test hash size nnn\n"
        "  -u nnn = Use hash size nnn\n"
        "  -v = toggle Verbose flag\n"
        "  Each token is hashed.\n", argv0 );
}   /* end usage */

//****************************************************************
//  FNV32 Test
//****************************************************************
void Test32 ( void ) {
    int         i, err;
    long int    iLen;
    uint32_t    FNV32basisT = FNV32basis;
    uint32_t    FNV32svalues[NTstrings] = {
        0x811c9dc5, 0xe40c292c, 0xbf9cf968, 0xfd9d3881 };
    uint32_t    FNV32bvalues[NTstrings] = {
        0x050c5d1f, 0x2b24d044, 0x0c1c9eb8, 0xbf7ff313 };

    funcName = "FNV-32";
    selected = FNV32selected;
/* test error checks */
    Terr = 0;
    TestR ( "init1", fnvSuccess, FNV32init (&e32Context) );
    CommonTest();
    TestR ( "string1i", fnvNull,
            FNV32INTstring ( (char *)0, &eUint32 ) );
    TestR ( "string2i", fnvNull,
            FNV32INTstring ( errteststring, (uint32_t *)0 ) );
    TestR ( "block1i", fnvNull,
            FNV32INTblock ( (uint8_t *)0, 1, &eUint32 ) );
    TestR ( "block2i", fnvBadParam,
            FNV32INTblock ( errtestbytes, -1, &eUint32 ) );
    TestR ( "block3i", fnvNull,
            FNV32INTblock ( errtestbytes, 1, (uint32_t *)0 ) );
    TestR ( "init2", fnvNull,
            FNV32init ( (FNV32context *)0 ) );
    TestR ( "initBasis1i", fnvNull,
            FNV32INTinitBasis ( (FNV32context *)0, eUint32 ) );
    TestR ( "initBasis1b", fnvNull,
            FNV32initBasis ( (FNV32context *)0, hash ) );
    TestR ( "blockin1", fnvNull,
            FNV32blockin ( (FNV32context *)0,
                           errtestbytes, NTestBytes ) );
    TestR ( "blockin2", fnvNull,
            FNV32blockin ( &e32Context, (uint8_t *)0,
                           NTestBytes ) );
    TestR ( "blockin3", fnvBadParam,
            FNV32blockin ( &e32Context, errtestbytes, -1 ) );
    e32Context.Computed = FNVclobber+FNV32state;
    TestR ( "blockin4", fnvStateError,
            FNV32blockin ( &e32Context, errtestbytes,
                           NTestBytes ) );
    TestR ( "stringin1", fnvNull,
            FNV32stringin ( (FNV32context *)0, errteststring ) );
    TestR ( "stringin2", fnvNull,
            FNV32stringin ( &e32Context, (char *)0 ) );
    TestR ( "stringin3", fnvStateError,
            FNV32stringin ( &e32Context, errteststring ) );
    TestR ( "result1i", fnvNull,
            FNV32INTresult ( (FNV32context *)0, &eUint32 ) );
    TestR ( "result2i", fnvNull,
            FNV32INTresult ( &e32Context, (uint32_t *)0  ) );
    TestR ( "result3i", fnvStateError,
            FNV32INTresult ( &e32Context, &eUint32  ) );
    TestR ( "result1b", fnvNull,
            FNV32result ( (FNV32context *)0, hash ) );
    TestR ( "result2b", fnvNull,
            FNV32result ( &e32Context, (uint8_t *)0  ) );
    TestR ( "result3b", fnvStateError,
            FNV32result ( &e32Context, hash  ) );
    TestR ( "file1i", fnvNull,
            FNV32INTfile ( (char *)0, &eUint32 ));
    TestR ( "file2i", fnvNull,
            FNV32INTfile ( "foo.txt", (uint32_t *)0 ));
    ErrTestReport ();
/* test actual results int */
    Terr = 0;
    for ( i = 0; i < NTstrings; ++i ) {
        err = TestR ( "stringai", fnvSuccess,
                      FNV32INTstring ( teststring[i], &eUint32 ) );
        if ( err == fnvSuccess )
            TestNValue ( "stringbi", teststring[i], FNV32size,
                         (uint8_t *)&eUint32,
                         (uint8_t *)&FNV32svalues[i] );
        err = TestR ( "blockai", fnvSuccess,
                      FNV32INTblock ( (uint8_t *)teststring[i],
                           (unsigned long)(strlen(teststring[i])+1),
                           &eUint32 ) );
        if ( err == fnvSuccess )
            TestNValue ( "blockbi", teststring[i], FNV32size,
                         (uint8_t *)&eUint32,
                         (uint8_t *)&FNV32bvalues[i] );
/* test actual results byte */
        err = TestR ( "stringab", fnvSuccess,
                      FNV32string ( teststring[i], hash ) );
        if ( err == fnvSuccess )
            TestNValue ( "stringbb", teststring[i], FNV32size,
                         hash, (uint8_t *)&FNV32svalues[i] );
        err = TestR ( "blockab", fnvSuccess,
                      FNV32block ( (uint8_t *)teststring[i],
                           (unsigned long)(strlen(teststring[i])+1),
                           hash ) );
        if ( err == fnvSuccess )
            TestNValue ( "blockbb", teststring[i], FNV32size,
                         hash, (uint8_t *)&FNV32bvalues[i] );
/* now try testing the incremental stuff int */
        err = TestR ( "inita", fnvSuccess,
                      FNV32init (&e32Context) );
        if ( err ) break;
        iLen = strlen ( teststring[i] );
        err = TestR ( "blockinai", fnvSuccess,
                      FNV32blockin ( &e32Context,
                                     (uint8_t *)teststring[i],
                                     iLen/2 ) );
        if ( err ) break;
        err = TestR ( "stringinai", fnvSuccess,
                      FNV32stringin ( &e32Context,
                                    teststring[i] + iLen/2 ) );
        if ( err ) break;
        err = TestR ( "resultai", fnvSuccess,
                      FNV32INTresult ( &e32Context, &eUint32 ) );
        if ( err ) break;
        TestNValue ( "incrementalai", teststring[i], FNV32size,
                     (uint8_t *)&eUint32,
                     (uint8_t *)&FNV32svalues[i] );
/* now try testing the incremental stuff byte */
        err = TestR ( "initabb", fnvSuccess,
                      FNV32initBasis (&e32Context,
                                      (uint8_t *)&FNV32basisT) );
        if ( err ) break;
        iLen = strlen ( teststring[i] );
        err = TestR ( "blockinab", fnvSuccess,
                      FNV32blockin ( &e32Context,
                                     (uint8_t *)teststring[i],
                                     iLen/2 ) );
        if ( err ) break;
        err = TestR ( "stringinab", fnvSuccess,
                      FNV32stringin ( &e32Context,
                                    teststring[i] + iLen/2 ) );
        if ( err ) break;
        err = TestR ( "resultab", fnvSuccess,
                      FNV32result ( &e32Context, hash ) );
        if ( err ) break;
        TestNValue ( "incrementalab", teststring[i], FNV32size,
                     hash, (uint8_t *)&FNV32svalues[i] );

/* now try testing file int */
        err = TestR ( "fileafi", fnvSuccess,
                      FNV32INTfile (
                                    WriteTemp(teststring[i], iLen),
                                    &eUint32 )
                      );
        if ( err ) break;
        TestNValue ( "filebfi", teststring[i], FNV32size,
                         (uint8_t *)&eUint32,
                         (uint8_t *)&FNV32svalues[i] );

/* now try testing file hash */
        err = TestR ( "fileafh", fnvSuccess,
                      FNV32file (
                                 WriteTemp(teststring[i], iLen),
                                 hash )
                      );
        if ( err ) break;
        TestNValue ( "filebfh", teststring[i], FNV32size,
                     hash,
                     (uint8_t *)&FNV32svalues[i] );

    }   // end for i
    ValueTestReport ();
}    /* end Test32 */

#ifdef FNV_64bitIntegers
//****************************************************************
//  Code for testing FNV64 using 64-bit integers
//****************************************************************
void Test64 ( void ) { /* with 64-bit integers */
    int        i, err;
    long int   iLen;
    uint64_t   FNV64basisT = FNV64basis;
    uint64_t   FNV64svalues[NTstrings] = {
        0xcbf29ce484222325, 0xaf63dc4c8601ec8c, 0x85944171f73967e8,
        0xbd51ea7094ee6fa1 };
    uint64_t   FNV64bvalues[NTstrings] = {
        0xaf63bd4c8601b7df, 0x089be207b544f1e4, 0x34531ca7168b8f38,
        0xa0a0fe4d1127ae93 };

    funcName = "FNV-64";
    selected = FNV64selected;
/* test error checks */
    Terr = 0;
    TestR ( "init1", fnvSuccess, FNV64init (&e64Context) );
    CommonTest();
    TestR ( "string1i", fnvNull,
           FNV64INTstring ( (char *)0, &eUint64 ) );
    TestR ( "string2i", fnvNull,
           FNV64INTstring ( errteststring, (uint64_t *)0 ) );
    TestR ( "block1i", fnvNull,
           FNV64INTblock ( (uint8_t *)0, 1, &eUint64 ) );
    TestR ( "block2i", fnvBadParam,
           FNV64INTblock ( errtestbytes, -1, &eUint64 ) );
    TestR ( "block3i", fnvNull,
           FNV64INTblock ( errtestbytes, 1, (uint64_t *)0 ) );
    TestR ( "init2", fnvNull,
           FNV64init ( (FNV64context *)0 ) );
    TestR ( "initBasis1i", fnvNull,
           FNV64INTinitBasis ( (FNV64context *)0, eUint64 ) );
    TestR ( "initBasis1b", fnvNull,
           FNV64initBasis ( (FNV64context *)0, hash ) );
    TestR ( "blockin1", fnvNull,
           FNV64blockin ( (FNV64context *)0,
                         errtestbytes, NTestBytes ) );
    TestR ( "blockin2", fnvNull,
           FNV64blockin ( &e64Context, (uint8_t *)0,
                         NTestBytes ) );
    TestR ( "blockin3", fnvBadParam,
           FNV64blockin ( &e64Context, errtestbytes, -1 ) );
    e64Context.Computed = FNVclobber+FNV64state;
    TestR ( "blockin4", fnvStateError,
           FNV64blockin ( &e64Context, errtestbytes,
                         NTestBytes ) );
    TestR ( "stringin1", fnvNull,
           FNV64stringin ( (FNV64context *)0, errteststring ) );
    TestR ( "stringin2", fnvNull,
           FNV64stringin ( &e64Context, (char *)0 ) );
    TestR ( "stringin3", fnvStateError,
           FNV64stringin ( &e64Context, errteststring ) );
    TestR ( "result1i", fnvNull,
           FNV64INTresult ( (FNV64context *)0, &eUint64 ) );
    TestR ( "result2i", fnvNull,
           FNV64INTresult ( &e64Context, (uint64_t *)0  ) );
    TestR ( "result3i", fnvStateError,
           FNV64INTresult ( &e64Context, &eUint64  ) );
    TestR ( "result1b", fnvNull,
           FNV64INTresult ( (FNV64context *)0, &eUint64 ) );
    TestR ( "result2b", fnvNull,
           FNV64INTresult ( &e64Context, (uint64_t *)0  ) );
    TestR ( "result3b", fnvStateError,
           FNV64INTresult ( &e64Context, &eUint64  ) );
    TestR ( "file1i", fnvNull,
            FNV64INTfile ( (char *)0, &eUint64 ));
    TestR ( "file2i", fnvNull,
            FNV64INTfile ( "foo.txt", (uint64_t *)0 ));
    ErrTestReport ();
/* test actual results int */
    Terr = 0;
    for ( i = 0; i < NTstrings; ++i ) {
        err = TestR ( "stringai", fnvSuccess,
                     FNV64INTstring ( teststring[i], &eUint64 ) );
        if ( err == fnvSuccess )
            TestNValue ( "stringbi", teststring[i], FNV64size,
                        (uint8_t *)&eUint64,
                        (uint8_t *)&FNV64svalues[i] );
        err = TestR ( "blockai", fnvSuccess,
                     FNV64INTblock ( (uint8_t *)teststring[i],
                          (unsigned long)(strlen(teststring[i])+1),
                                    &eUint64 ) );
        if ( err == fnvSuccess )
            TestNValue ( "blockbi", teststring[i], FNV64size,
                        (uint8_t *)&eUint64,
                        (uint8_t *)&FNV64bvalues[i] );
/* test actual results byte */
        err = TestR ( "stringab", fnvSuccess,
                     FNV64string ( teststring[i], hash ) );
        if ( err == fnvSuccess )
            TestNValue ( "stringbb", teststring[i], FNV64size,
                        hash, (uint8_t *)&FNV64svalues[i] );
        err = TestR ( "blockab", fnvSuccess,
                     FNV64block ( (uint8_t *)teststring[i],
                          (unsigned long)(strlen(teststring[i])+1),
                                 hash ) );
        if ( err == fnvSuccess )
            TestNValue ( "blockb", teststring[i], FNV64size,
                        hash, (uint8_t *)&FNV64bvalues[i] );
/* now try testing the incremental stuff int */
        err = TestR ( "initai", fnvSuccess,
                     FNV64init (&e64Context) );
        if ( err ) break;
        iLen = strlen ( teststring[i] );
        err = TestR ( "blockinai", fnvSuccess,
                     FNV64blockin ( &e64Context,
                                   (uint8_t *)teststring[i],
                                   iLen/2 ) );
        if ( err ) break;
        err = TestR ( "stringinai", fnvSuccess,
                     FNV64stringin ( &e64Context,
                                    teststring[i] + iLen/2 ) );
        if ( err ) break;
        err = TestR ( "resultai", fnvSuccess,
                     FNV64INTresult ( &e64Context, &eUint64 ) );
        if ( err ) break;
        TestNValue ( "incrementalai", teststring[i], FNV64size,
                    (uint8_t *)&eUint64,
                    (uint8_t *)&FNV64svalues[i] );
/* now try testing the incremental stuff byte */
        err = TestR ( "initab", fnvSuccess,
                     FNV64initBasis (&e64Context,
                                     (uint8_t *)&FNV64basisT) );
        if ( err ) break;
        iLen = strlen ( teststring[i] );
        err = TestR ( "blockinab", fnvSuccess,
                     FNV64blockin ( &e64Context,
                                   (uint8_t *)teststring[i],
                                   iLen/2 ) );
        if ( err ) break;
        err = TestR ( "stringinab", fnvSuccess,
                     FNV64stringin ( &e64Context,
                                    teststring[i] + iLen/2 ) );
        if ( err ) break;
        err = TestR ( "resultab", fnvSuccess,
                     FNV64result ( &e64Context, hash ) );
        if ( err ) break;
        TestNValue ( "incrementala", teststring[i], FNV64size,
                    hash, (uint8_t *)&FNV64svalues[i] );

/* now try testing file int */
        err = TestR ( "fileafi", fnvSuccess,
                      FNV64INTfile (
                                    WriteTemp(teststring[i], iLen),
                                    &eUint64 )
                      );
        if ( err ) break;
        TestNValue ( "filebfi", teststring[i], FNV64size,
                         (uint8_t *)&eUint64,
                         (uint8_t *)&FNV64svalues[i] );

/* now try testing file hash */
        err = TestR ( "fileafh", fnvSuccess,
                      FNV64file (
                                 WriteTemp(teststring[i], iLen),
                                 hash )
                      );
        if ( err ) break;
        TestNValue ( "filebfh", teststring[i], FNV64size,
                     hash,
                     (uint8_t *)&FNV64svalues[i] );

    }
    ValueTestReport ();
}   /* end Test64 */

#else

//****************************************************************
//  Code for testing FNV64 without 64-bit integers
//****************************************************************
void Test64 ( void ) { /* without 64-bit integers */
    int    i, err;
    long int   iLen;
    uint8_t   FNV64svalues[NTstrings][FNV64size] = {
        { 0xcb, 0xf2, 0x9c, 0xe4, 0x84, 0x22, 0x23, 0x25 },
        { 0xaf, 0x63, 0xdc, 0x4c, 0x86, 0x01, 0xec, 0x8c },
        { 0x85, 0x94, 0x41, 0x71, 0xf7, 0x39, 0x67, 0xe8 },
        { 0xbd, 0x51, 0xea, 0x70, 0x94, 0xee, 0x6f, 0xa1 } };
    uint8_t   FNV64bvalues[NTstrings][FNV64size] = {
        { 0xaf, 0x63, 0xbd, 0x4c, 0x86, 0x01, 0xb7, 0xdf },
        { 0x08, 0x9b, 0xe2, 0x07, 0xb5, 0x44, 0xf1, 0xe4 },
        { 0x34, 0x53, 0x1c, 0xa7, 0x16, 0x8b, 0x8f, 0x38 },
        { 0xa0, 0xa0, 0xfe, 0x4d, 0x11, 0x27, 0xae, 0x93 } };

    funcName = "FNV-64";
    selected = FNV64selected;
/* test error checks */
    Terr = 0;
    TestR ( "init1", fnvSuccess, FNV64init (&e64Context) );
    CommonTest();
    TestR ( "init2", fnvNull,
            FNV64init ( (FNV64context *)0 ) );
    TestR ( "initBasis1", fnvNull,
            FNV64initBasis ( (FNV64context *)0, hash ) );
    TestR ( "blockin1", fnvNull,
            FNV64blockin ( (FNV64context *)0,
                           errtestbytes, NTestBytes ) );
    TestR ( "blockin2", fnvNull,
            FNV64blockin ( &e64Context, (uint8_t *)0,
                           NTestBytes ) );
    TestR ( "blockin3", fnvBadParam,
            FNV64blockin ( &e64Context, errtestbytes, -1 ) );
    e64Context.Computed = FNVclobber+FNV64state;
    TestR ( "blockin4", fnvStateError,
            FNV64blockin ( &e64Context, errtestbytes,
                           NTestBytes ) );
    TestR ( "stringin1", fnvNull,
            FNV64stringin ( (FNV64context *)0, errteststring ) );
    TestR ( "stringin2", fnvNull,
            FNV64stringin ( &e64Context, (char *)0 ) );
    TestR ( "stringin3", fnvStateError,
            FNV64stringin ( &e64Context, errteststring ) );
    TestR ( "result1", fnvNull,
            FNV64result ( (FNV64context *)0, hash ) );
    TestR ( "result2", fnvNull,
            FNV64result ( &e64Context, (uint8_t *)0  ) );
    TestR ( "result3", fnvStateError,
            FNV64result ( &e64Context, hash ) );
    ErrTestReport ();
/* test actual results */
    Terr = 0;
    for ( i = 0; i < NTstrings; ++i ) {
        err = TestR ( "stringa", fnvSuccess,
                      FNV64string ( teststring[i], hash ) );
        if ( err == fnvSuccess )
            TestNValue ( "stringb", teststring[i], FNV64size,
                         hash, FNV64svalues[i] );
        err = TestR ( "blocka", fnvSuccess,
                      FNV64block ( (uint8_t *)teststring[i],
                          (unsigned long)(strlen(teststring[i])+1),
                          hash ) );
        if ( err == fnvSuccess )
            TestNValue ( "blockb", teststring[i], FNV64size,
                         hash,
                         FNV64bvalues[i] );
/* now try testing the incremental stuff */
        err = TestR ( "inita", fnvSuccess,
                      FNV64init ( &e64Context ) );
        if ( err ) break;
        iLen = strlen ( teststring[i] );
        err = TestR ( "blockina", fnvSuccess,
                      FNV64blockin ( &e64Context,
                                     (uint8_t *)teststring[i],
                                     iLen/2 ) );
        if ( err ) break;
        err = TestR ( "stringina", fnvSuccess,
                      FNV64stringin ( &e64Context,
                                      teststring[i] + iLen/2 ) );
        if ( err ) break;
        err = TestR ( "resulta", fnvSuccess,
                      FNV64result ( &e64Context, hash ) );
        if ( err ) break;
        TestNValue ( "incrementala", teststring[i], FNV64size,
                     hash, (uint8_t *)&FNV64svalues[i] );

/* now try testing file hash */
        err = TestR ( "fileafh", fnvSuccess,
                      FNV64file (
                                 WriteTemp(teststring[i], iLen),
                                 hash )
                      );
        if ( err ) break;
        TestNValue ( "filebfh", teststring[i], FNV64size,
                     hash,
                     (uint8_t *)&FNV64svalues[i] );

    }
    ValueTestReport ();
}   /* end Test64 */
#endif /* FNV_64bitIntegers */

//****************************************************************
//  Code for testing FNV128
//****************************************************************
void Test128 ( void ) {
    int        i, err;
    long int   iLen;
    uint8_t   FNV128svalues[NTstrings][FNV128size] = {
        { 0x6c, 0x62, 0x27, 0x2e, 0x07, 0xbb, 0x01, 0x42,
          0x62, 0xb8, 0x21, 0x75, 0x62, 0x95, 0xc5, 0x8d },
        { 0xd2, 0x28, 0xcb, 0x69, 0x6f, 0x1a, 0x8c, 0xaf,
          0x78, 0x91, 0x2b, 0x70, 0x4e, 0x4a, 0x89, 0x64 },
        { 0x34, 0x3e, 0x16, 0x62, 0x79, 0x3c, 0x64, 0xbf,
          0x6f, 0x0d, 0x35, 0x97, 0xba, 0x44, 0x6f, 0x18 },
        { 0x74, 0x20, 0x2c, 0x60, 0x0b, 0x05, 0x1c, 0x16,
          0x5b, 0x1a, 0xca, 0xfe, 0xd1, 0x0d, 0x14, 0x19 } };
    uint8_t   FNV128bvalues[NTstrings][FNV128size] = {
        { 0xd2, 0x28, 0xcb, 0x69, 0x10, 0x1a, 0x8c, 0xaf,
          0x78, 0x91, 0x2b, 0x70, 0x4e, 0x4a, 0x14, 0x7f },
        { 0x08, 0x80, 0x95, 0x45, 0x19, 0xab, 0x1b, 0xe9,
          0x5a, 0xa0, 0x73, 0x30, 0x55, 0xb7, 0x0e, 0x0c },
        { 0xe0, 0x1f, 0xcf, 0x9a, 0x45, 0x4f, 0xf7, 0x8d,
          0xa5, 0x40, 0xf1, 0xb2, 0x32, 0x34, 0xb2, 0x88 },
        { 0xe2, 0x67, 0xa7, 0x41, 0xa8, 0x49, 0x8f, 0x82,
          0x19, 0xf7, 0xc7, 0x8b, 0x3b, 0x17, 0xba, 0xc3 } };

    funcName = "FNV-128";
    selected = FNV128selected;
/* test error checks */
    Terr = 0;
    TestR ( "init1", fnvSuccess, FNV128init (&e128Context) );
    CommonTest();
    TestR ( "init2", fnvNull,
            FNV128init ( (FNV128context *)0 ) );
    TestR ( "initBasis1", fnvNull,
            FNV128initBasis ( (FNV128context *)0, hash ) );
    TestR ( "blockin1", fnvNull,
            FNV128blockin ( (FNV128context *)0,
                           errtestbytes, NTestBytes ) );
    TestR ( "blockin2", fnvNull,
            FNV128blockin ( &e128Context, (uint8_t *)0,
                           NTestBytes ) );
    TestR ( "blockin3", fnvBadParam,
            FNV128blockin ( &e128Context, errtestbytes, -1 ) );
    e128Context.Computed = FNVclobber+FNV128state;
    TestR ( "blockin4", fnvStateError,
            FNV128blockin ( &e128Context, errtestbytes,
                           NTestBytes ) );
    TestR ( "stringin1", fnvNull,
            FNV128stringin ( (FNV128context *)0, errteststring ) );
    TestR ( "stringin2", fnvNull,
            FNV128stringin ( &e128Context, (char *)0 ) );
    TestR ( "stringin3", fnvStateError,
            FNV128stringin ( &e128Context, errteststring ) );
    TestR ( "result1", fnvNull,
            FNV128result ( (FNV128context *)0, hash ) );
    TestR ( "result2", fnvNull,
            FNV128result ( &e128Context, (uint8_t *)0  ) );
    TestR ( "result3", fnvStateError,
            FNV128result ( &e128Context, hash  ) );
    ErrTestReport ();
/* test actual results */
    Terr = 0;
    for ( i = 0; i < NTstrings; ++i ) {
        err = TestR ( "stringa", fnvSuccess,
                      FNV128string ( teststring[i], hash ) );
        if ( err == fnvSuccess )
            TestNValue ( "stringb", teststring[i], FNV128size,
                             hash,
                     FNV128svalues[i] );
        err = TestR ( "blocka", fnvSuccess,
                      FNV128block ( (uint8_t *)teststring[i],
                          (unsigned long)(strlen(teststring[i])+1),
                          hash ) );
        if ( err == fnvSuccess )
            TestNValue ( "blockb", teststring[i], FNV128size,
                         hash,
                         FNV128bvalues[i] );
/* now try testing the incremental stuff */
        err = TestR ( "inita", fnvSuccess,
                      FNV128init ( &e128Context ) );
        if ( err ) break;
        iLen = strlen ( teststring[i] );
        err = TestR ( "blockina", fnvSuccess,
                      FNV128blockin ( &e128Context,
                      (uint8_t *)teststring[i],
                      iLen/2 ) );
        if ( err ) break;
        err = TestR ( "stringina", fnvSuccess,
                      FNV128stringin ( &e128Context,
                      teststring[i] + iLen/2 ) );
        if ( err ) break;
        err = TestR ( "resulta", fnvSuccess,
                      FNV128result ( &e128Context, hash ) );
        if ( err ) break;
        TestNValue ( "incrementala", teststring[i], FNV128size,
                     hash,
                     (uint8_t *)&FNV128svalues[i] );

/* now try testing file hash */
        err = TestR ( "fileafh", fnvSuccess,
                      FNV128file (
                                 WriteTemp(teststring[i], iLen),
                                 hash )
                      );
        if ( err ) break;
        TestNValue ( "filebfh", teststring[i], FNV128size,
                     hash,
                     (uint8_t *)&FNV128svalues[i] );

     }
    ValueTestReport ();
}    /* end Test128 */

//****************************************************************
//  Code for testing FNV256
//****************************************************************
void Test256 ( void ) {
    int        i, err;
    long int   iLen;
    uint8_t   FNV256svalues[NTstrings][FNV256size] = {
        { 0xdd, 0x26, 0x8d, 0xbc, 0xaa, 0xc5, 0x50, 0x36,
          0x2d, 0x98, 0xc3, 0x84, 0xc4, 0xe5, 0x76, 0xcc,
          0xc8, 0xb1, 0x53, 0x68, 0x47, 0xb6, 0xbb, 0xb3,
          0x10, 0x23, 0xb4, 0xc8, 0xca, 0xee, 0x05, 0x35 },
        { 0x63, 0x32, 0x3f, 0xb0, 0xf3, 0x53, 0x03, 0xec,
          0x28, 0xdc, 0x75, 0x1d, 0x0a, 0x33, 0xbd, 0xfa,
          0x4d, 0xe6, 0xa9, 0x9b, 0x72, 0x66, 0x49, 0x4f,
          0x61, 0x83, 0xb2, 0x71, 0x68, 0x11, 0x63, 0x7c },
        { 0xb0, 0x55, 0xea, 0x2f, 0x30, 0x6c, 0xad, 0xad,
          0x4f, 0x0f, 0x81, 0xc0, 0x2d, 0x38, 0x89, 0xdc,
          0x32, 0x45, 0x3d, 0xad, 0x5a, 0xe3, 0x5b, 0x75,
          0x3b, 0xa1, 0xa9, 0x10, 0x84, 0xaf, 0x34, 0x28 },
        { 0x0c, 0x5a, 0x44, 0x40, 0x2c, 0x65, 0x38, 0xcf,
          0x98, 0xef, 0x20, 0xc4, 0x03, 0xa8, 0x0f, 0x65,
          0x9b, 0x80, 0xc9, 0xa5, 0xb0, 0x1a, 0x6a, 0x87,
          0x34, 0x2e, 0x26, 0x72, 0x64, 0x45, 0x67, 0xb1 } };
    uint8_t   FNV256bvalues[NTstrings][FNV256size] = {
        { 0x63, 0x32, 0x3f, 0xb0, 0xf3, 0x53, 0x03, 0xec,
          0x28, 0xdc, 0x56, 0x1d, 0x0a, 0x33, 0xbd, 0xfa,
          0x4d, 0xe6, 0xa9, 0x9b, 0x72, 0x66, 0x49, 0x4f,
          0x61, 0x83, 0xb2, 0x71, 0x68, 0x11, 0x38, 0x7f },
        { 0xf4, 0xf7, 0xa1, 0xc2, 0xef, 0xd0, 0xe1, 0xe4,
          0xbb, 0x19, 0xe3, 0x45, 0x25, 0xc0, 0x72, 0x1a,
          0x06, 0xdd, 0x32, 0x8f, 0xa3, 0xd7, 0xa9, 0x14,
          0x39, 0xa0, 0x73, 0x43, 0x50, 0x1c, 0xf4, 0xf4 },
        { 0x6a, 0x7f, 0x34, 0xab, 0xc8, 0x5d, 0xe7, 0xd9,
          0x51, 0xb5, 0x15, 0x7e, 0xb5, 0x67, 0x2c, 0x59,
          0xb6, 0x04, 0x87, 0x65, 0x09, 0x47, 0xd3, 0x91,
          0xb1, 0x2d, 0x71, 0xe7, 0xfe, 0xf5, 0x53, 0x78 },
        { 0x3b, 0x97, 0x2c, 0x31, 0xbe, 0x84, 0x3a, 0x45,
          0x59, 0x02, 0x20, 0xd1, 0x12, 0x0d, 0x59, 0xe6,
          0xa3, 0x97, 0xa0, 0xc3, 0x34, 0xa1, 0xb9, 0x7d,
          0x5b, 0xff, 0x50, 0xa1, 0x0c, 0x3e, 0xca, 0x73 } };

    funcName = "FNV-256";
    selected = FNV256selected;
/* test error checks */
    Terr = 0;
    TestR ( "init1", fnvSuccess, FNV256init (&e256Context) );
    CommonTest();
    TestR ( "init2", fnvNull,
            FNV256init ( (FNV256context *)0 ) );
    TestR ( "initBasis1", fnvNull,
            FNV256initBasis ( (FNV256context *)0, hash ) );
    TestR ( "blockin1", fnvNull,
            FNV256blockin ( (FNV256context *)0,
                           errtestbytes, NTestBytes ) );
    TestR ( "blockin2", fnvNull,
            FNV256blockin ( &e256Context, (uint8_t *)0,
                           NTestBytes ) );
    TestR ( "blockin3", fnvBadParam,
            FNV256blockin ( &e256Context, errtestbytes, -1 ) );
    e256Context.Computed = FNVclobber+FNV256state;
    TestR ( "blockin4", fnvStateError,
            FNV256blockin ( &e256Context, errtestbytes,
                            NTestBytes ) );
    TestR ( "stringin1", fnvNull,
            FNV256stringin ( (FNV256context *)0, errteststring ) );
    TestR ( "stringin2", fnvNull,
            FNV256stringin ( &e256Context, (char *)0 ) );
    TestR ( "stringin3", fnvStateError,
            FNV256stringin ( &e256Context, errteststring ) );
    TestR ( "result1", fnvNull,
            FNV256result ( (FNV256context *)0, hash ) );
    TestR ( "result2", fnvNull,
            FNV256result ( &e256Context, (uint8_t *)0  ) );
    TestR ( "result3", fnvStateError,
            FNV256result ( &e256Context, hash  ) );
    ErrTestReport ();
/* test actual results */
    Terr = 0;
    for ( i = 0; i < NTstrings; ++i ) {
        err = TestR ( "stringa", fnvSuccess,
                      FNV256string ( teststring[i], hash ) );
        if ( err == fnvSuccess )
            TestNValue ( "stringb", teststring[i], FNV256size,
                             hash,
                     FNV256svalues[i] );
        err = TestR ( "blocka", fnvSuccess,
                      FNV256block ( (uint8_t *)teststring[i],
                          (unsigned long)(strlen(teststring[i])+1),
                          hash ) );
        if ( err == fnvSuccess )
            TestNValue ( "blockb", teststring[i], FNV256size,
                     hash,
                     FNV256bvalues[i] );
/* now try testing the incremental stuff */
        err = TestR ( "inita", fnvSuccess,
                      FNV256init ( &e256Context ) );
        if ( err ) break;
        iLen = strlen ( teststring[i] );
        err = TestR ( "blockina", fnvSuccess,
                      FNV256blockin ( &e256Context,
                      (uint8_t *)teststring[i],
                      iLen/2 ) );
        if ( err ) break;
        err = TestR ( "stringina", fnvSuccess,
                      FNV256stringin ( &e256Context,
                      teststring[i] + iLen/2 ) );
        if ( err ) break;
        err = TestR ( "resulta", fnvSuccess,
                      FNV256result ( &e256Context, hash ) );
        if ( err == fnvSuccess )
            TestNValue ( "incrementala", teststring[i], FNV256size,
                     hash,
                     (uint8_t *)&FNV256svalues[i] );

/* now try testing file hash */
        err = TestR ( "fileafh", fnvSuccess,
                      FNV256file (
                                 WriteTemp(teststring[i], iLen),
                                 hash )
                      );
        if ( err ) break;
        TestNValue ( "filebfh", teststring[i], FNV256size,
                     hash,
                     (uint8_t *)&FNV256svalues[i] );

    }
    ValueTestReport ();
}    /* end Test256 */

//****************************************************************
//  Code for testing FNV512
//****************************************************************
void Test512 ( void ) {
    int        i, err;
    long int   iLen;
    uint8_t   FNV512svalues[NTstrings][FNV512size] = {
        { 0xb8, 0x6d, 0xb0, 0xb1, 0x17, 0x1f, 0x44, 0x16,
          0xdc, 0xa1, 0xe5, 0x0f, 0x30, 0x99, 0x90, 0xac,
          0xac, 0x87, 0xd0, 0x59, 0xc9, 0x00, 0x00, 0x00,
          0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x0d, 0x21,
          0xe9, 0x48, 0xf6, 0x8a, 0x34, 0xc1, 0x92, 0xf6,
          0x2e, 0xa7, 0x9b, 0xc9, 0x42, 0xdb, 0xe7, 0xce,
          0x18, 0x20, 0x36, 0x41, 0x5f, 0x56, 0xe3, 0x4b,
          0xac, 0x98, 0x2a, 0xac, 0x4a, 0xfe, 0x9f, 0xd9 },
        { 0xe4, 0x3a, 0x99, 0x2d, 0xc8, 0xfc, 0x5a, 0xd7,
          0xde, 0x49, 0x3e, 0x3d, 0x69, 0x6d, 0x6f, 0x85,
          0xd6, 0x43, 0x26, 0xec, 0x07, 0x00, 0x00, 0x00,
          0x00, 0x00, 0x00, 0x00, 0x00, 0x11, 0x98, 0x6f,
          0x90, 0xc2, 0x53, 0x2c, 0xaf, 0x5b, 0xe7, 0xd8,
          0x82, 0x91, 0xba, 0xa8, 0x94, 0xa3, 0x95, 0x22,
          0x53, 0x28, 0xb1, 0x96, 0xbd, 0x6a, 0x8a, 0x64,
          0x3f, 0xe1, 0x2c, 0xd8, 0x7b, 0x27, 0xff, 0x88 },
        { 0xb0, 0xec, 0x73, 0x8d, 0x9c, 0x6f, 0xd9, 0x69,
          0xd0, 0x5f, 0x0b, 0x35, 0xf6, 0xc0, 0xed, 0x53,
          0xad, 0xca, 0xcc, 0xcd, 0x8e, 0x00, 0x00, 0x00,
          0x4b, 0xf9, 0x9f, 0x58, 0xee, 0x41, 0x96, 0xaf,
          0xb9, 0x70, 0x0e, 0x20, 0x11, 0x08, 0x30, 0xfe,
          0xa5, 0x39, 0x6b, 0x76, 0x28, 0x0e, 0x47, 0xfd,
          0x02, 0x2b, 0x6e, 0x81, 0x33, 0x1c, 0xa1, 0xa9,
          0xce, 0xd7, 0x29, 0xc3, 0x64, 0xbe, 0x77, 0x88 },
        { 0x4f, 0xdf, 0x00, 0xec, 0xb9, 0xbc, 0x04, 0xdd,
          0x19, 0x38, 0x61, 0x8f, 0xe5, 0xc4, 0xfb, 0xb8,
          0x80, 0xa8, 0x2b, 0x15, 0xf5, 0xb6, 0xbd, 0x72,
          0x1e, 0xc2, 0xea, 0xfe, 0x03, 0xc4, 0x62, 0x48,
          0xf7, 0xa6, 0xc2, 0x47, 0x89, 0x92, 0x80, 0xd6,
          0xd2, 0xf4, 0x2f, 0xf6, 0xb4, 0x7b, 0xf2, 0x20,
          0x79, 0xdf, 0xd4, 0xbf, 0xe8, 0x7b, 0xf0, 0xbb,
          0x4e, 0x71, 0xea, 0xcb, 0x1e, 0x28, 0x77, 0x35 } };
    uint8_t   FNV512bvalues[NTstrings][FNV512size] = {
        { 0xe4, 0x3a, 0x99, 0x2d, 0xc8, 0xfc, 0x5a, 0xd7,
          0xde, 0x49, 0x3e, 0x3d, 0x69, 0x6d, 0x6f, 0x85,
          0xd6, 0x43, 0x26, 0xec, 0x28, 0x00, 0x00, 0x00,
          0x00, 0x00, 0x00, 0x00, 0x00, 0x11, 0x98, 0x6f,
          0x90, 0xc2, 0x53, 0x2c, 0xaf, 0x5b, 0xe7, 0xd8,
          0x82, 0x91, 0xba, 0xa8, 0x94, 0xa3, 0x95, 0x22,
          0x53, 0x28, 0xb1, 0x96, 0xbd, 0x6a, 0x8a, 0x64,
          0x3f, 0xe1, 0x2c, 0xd8, 0x7b, 0x28, 0x2b, 0xbf },
        { 0x73, 0x17, 0xdf, 0xed, 0x6c, 0x70, 0xdf, 0xec,
          0x6a, 0xdf, 0xce, 0xd2, 0xa5, 0xe0, 0x4d, 0x7e,
          0xec, 0x74, 0x4e, 0x3c, 0xe9, 0x00, 0x00, 0x00,
          0x00, 0x00, 0x00, 0x00, 0x17, 0x93, 0x3d, 0x7a,
          0xf4, 0x5d, 0x70, 0xde, 0xf4, 0x23, 0xa3, 0x16,
          0xf1, 0x41, 0x17, 0xdf, 0x27, 0x2c, 0xd0, 0xfd,
          0x6b, 0x85, 0xf0, 0xf7, 0xc9, 0xbf, 0x6c, 0x51,
          0x96, 0xb3, 0x16, 0x0d, 0x02, 0x97, 0x5f, 0x38 },
        { 0x82, 0xf6, 0xe1, 0x04, 0x96, 0xde, 0x78, 0x34,
          0xb0, 0x8b, 0x21, 0xef, 0x46, 0x4c, 0xd2, 0x47,
          0x9e, 0x1d, 0x25, 0xe0, 0xca, 0x00, 0x00, 0x65,
          0xcb, 0x74, 0x80, 0x27, 0x39, 0xe0, 0xe5, 0x71,
          0x75, 0x22, 0xec, 0xf6, 0xd1, 0xf9, 0xa5, 0x2f,
          0x5f, 0xee, 0xfb, 0x4f, 0xab, 0x22, 0x73, 0xfd,
          0xe8, 0x31, 0x0f, 0x1b, 0x7b, 0x5c, 0x9a, 0x84,
          0x22, 0x48, 0xf4, 0xcb, 0xfb, 0x32, 0x27, 0x38 },
        { 0xfa, 0x7e, 0xb9, 0x1e, 0xfb, 0x64, 0x64, 0x11,
          0x8a, 0x73, 0x33, 0xbd, 0x96, 0x3b, 0xb6, 0x1f,
          0x2c, 0x6f, 0xe2, 0xe3, 0x6c, 0xd7, 0xd3, 0xe7,
          0x37, 0x28, 0xda, 0x57, 0x0c, 0x1f, 0xaf, 0xc3,
          0xd0, 0x6e, 0x4d, 0xd9, 0x53, 0x4a, 0x9f, 0xd4,
          0xa5, 0x2c, 0x43, 0x8b, 0xd2, 0x11, 0x69, 0x83,
          0x4a, 0xe6, 0x0d, 0x20, 0x7e, 0x0f, 0x8a, 0xf6,
          0x1a, 0xa1, 0x96, 0x25, 0x68, 0x37, 0xb8, 0x03 } };

    funcName = "FNV-512";
    selected = FNV512selected;
/* test error checks */
    Terr = 0;
    TestR ( "init1", fnvSuccess, FNV512init (&e512Context) );
    CommonTest();
    TestR ( "init2", fnvNull,
            FNV512init ( (FNV512context *)0 ) );
    TestR ( "initBasis1", fnvNull,
            FNV512initBasis ( (FNV512context *)0, hash ) );
    TestR ( "blockin1", fnvNull,
            FNV512blockin ( (FNV512context *)0,
                           errtestbytes, NTestBytes ) );
    TestR ( "blockin2", fnvNull,
            FNV512blockin ( &e512Context, (uint8_t *)0,
                           NTestBytes ) );
    TestR ( "blockin3", fnvBadParam,
            FNV512blockin ( &e512Context, errtestbytes, -1 ) );
    e512Context.Computed = FNVclobber+FNV512state;
    TestR ( "blockin4", fnvStateError,
            FNV512blockin ( &e512Context, errtestbytes,
                           NTestBytes ) );
    TestR ( "stringin1", fnvNull,
            FNV512stringin ( (FNV512context *)0, errteststring ) );
    TestR ( "stringin2", fnvNull,
            FNV512stringin ( &e512Context, (char *)0 ) );
    TestR ( "stringin3", fnvStateError,
            FNV512stringin ( &e512Context, errteststring ) );
    TestR ( "result1", fnvNull,
            FNV512result ( (FNV512context *)0, hash ) );
    TestR ( "result2", fnvNull,
            FNV512result ( &e512Context, (uint8_t *)0  ) );
    TestR ( "result3", fnvStateError,
            FNV512result ( &e512Context, hash  ) );
    ErrTestReport ();
/* test actual results */
    Terr = 0;
    for ( i = 0; i < NTstrings; ++i ) {
        err = TestR ( "stringa", fnvSuccess,
                      FNV512string ( teststring[i], hash ) );
        if ( err == fnvSuccess )
            TestNValue ( "stringb", teststring[i], FNV512size,
                             hash,
                     FNV512svalues[i] );
        err = TestR ( "blocka", fnvSuccess,
                      FNV512block ( (uint8_t *)teststring[i],
                      (unsigned long)(strlen(teststring[i])+1),
                      hash ) );
        if ( err == fnvSuccess )
            TestNValue ( "blockb", teststring[i], FNV512size,
                     hash,
                     FNV512bvalues[i] );
/* now try testing the incremental stuff */
        err = TestR ( "inita", fnvSuccess,
                      FNV512init ( &e512Context ) );
        if ( err ) break;
        iLen = strlen ( teststring[i] );
        err = TestR ( "blockina", fnvSuccess,
                      FNV512blockin ( &e512Context,
                      (uint8_t *)teststring[i],
                      iLen/2 ) );
        if ( err ) break;
        err = TestR ( "stringina", fnvSuccess,
                      FNV512stringin ( &e512Context,
                      teststring[i] + iLen/2 ) );
        if ( err ) break;
        err = TestR ( "resulta", fnvSuccess,
                      FNV512result ( &e512Context, hash ) );
        if ( err == fnvSuccess )
            TestNValue ( "incrementala", teststring[i], FNV512size,
                     hash,
                     (uint8_t *)&FNV512svalues[i] );

/* now try testing file hash */
        err = TestR ( "fileafh", fnvSuccess,
                      FNV512file (
                                 WriteTemp(teststring[i], iLen),
                                 hash )
                      );
        if ( err ) break;
        TestNValue ( "filebfh", teststring[i], FNV512size,
                     hash,
                     (uint8_t *)&FNV512svalues[i] );

    }
    ValueTestReport ();
}    /* end Test512 */

//****************************************************************
//  Code for testing FNV1024
//****************************************************************
void Test1024 ( void ) {
    int        i, err;
    long int   iLen;
    uint8_t   FNV1024svalues[NTstrings][FNV1024size] = {
      { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x5f, 0x7a, 0x76, 0x75, 0x8e, 0xcc, 0x4d,
        0x32, 0xe5, 0x6d, 0x5a, 0x59, 0x10, 0x28, 0xb7,
        0x4b, 0x29, 0xfc, 0x42, 0x23, 0xfd, 0xad, 0xa1,
        0x6c, 0x3b, 0xf3, 0x4e, 0xda, 0x36, 0x74, 0xda,
        0x9a, 0x21, 0xd9, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x04, 0xc6, 0xd7,
        0xeb, 0x6e, 0x73, 0x80, 0x27, 0x34, 0x51, 0x0a,
        0x55, 0x5f, 0x25, 0x6c, 0xc0, 0x05, 0xae, 0x55,
        0x6b, 0xde, 0x8c, 0xc9, 0xc6, 0xa9, 0x3b, 0x21,
        0xaf, 0xf4, 0xb1, 0x6c, 0x71, 0xee, 0x90, 0xb3 },
      { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x98, 0xd7, 0xc1, 0x9f, 0xbc, 0xe6, 0x53, 0xdf,
        0x22, 0x1b, 0x9f, 0x71, 0x7d, 0x34, 0x90, 0xff,
        0x95, 0xca, 0x87, 0xfd, 0xae, 0xf3, 0x0d, 0x1b,
        0x82, 0x33, 0x72, 0xf8, 0x5b, 0x24, 0xa3, 0x72,
        0xf5, 0x0e, 0x57, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x07, 0x68, 0x5c, 0xd8,
        0x1a, 0x49, 0x1d, 0xbc, 0xcc, 0x21, 0xad, 0x06,
        0x64, 0x8d, 0x09, 0xa5, 0xc8, 0xcf, 0x5a, 0x78,
        0x48, 0x20, 0x54, 0xe9, 0x14, 0x70, 0xb3, 0x3d,
        0xde, 0x77, 0x25, 0x2c, 0xae, 0xf6, 0x95, 0xaa },
      { 0x00, 0x00, 0x06, 0x31, 0x17, 0x5f, 0xa7, 0xae,
        0x64, 0x3a, 0xd0, 0x87, 0x23, 0xd3, 0x12, 0xc9,
        0xfd, 0x02, 0x4a, 0xdb, 0x91, 0xf7, 0x7f, 0x6b,
        0x19, 0x58, 0x71, 0x97, 0xa2, 0x2b, 0xcd, 0xf2,
        0x37, 0x27, 0x16, 0x6c, 0x45, 0x72, 0xd0, 0xb9,
        0x85, 0xd5, 0xae, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x42,
        0x70, 0xd1, 0x1e, 0xf4, 0x18, 0xef, 0x08, 0xb8,
        0xa4, 0x9e, 0x1e, 0x82, 0x5e, 0x54, 0x7e, 0xb3,
        0x99, 0x37, 0xf8, 0x19, 0x22, 0x2f, 0x3b, 0x7f,
        0xc9, 0x2a, 0x0e, 0x47, 0x07, 0x90, 0x08, 0x88,
        0x84, 0x7a, 0x55, 0x4b, 0xac, 0xec, 0x98, 0xb0 },
      { 0xf6, 0xf7, 0x47, 0xaf, 0x25, 0xa9, 0xde, 0x26,
        0xe8, 0xa4, 0x93, 0x43, 0x1e, 0x31, 0xb4, 0xa1,
        0xed, 0x2a, 0x92, 0x30, 0x4a, 0xf6, 0xca, 0x97,
        0x6b, 0xc1, 0xd9, 0x6f, 0xfc, 0xad, 0x35, 0x24,
        0x4e, 0x8d, 0x38, 0x5d, 0x55, 0xf4, 0x2f, 0xdc,
        0xc8, 0xf2, 0x99, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0xf7, 0xca, 0x87, 0xce,
        0x43, 0x22, 0x7b, 0x98, 0xc1, 0x44, 0x60, 0x7e,
        0x67, 0xcc, 0x50, 0xaf, 0x99, 0xbc, 0xc5, 0xd1,
        0x51, 0x4b, 0xb0, 0xd9, 0x23, 0xee, 0xde, 0xdd,
        0x69, 0xe8, 0xe7, 0x47, 0x02, 0x05, 0x08, 0x3a,
        0x0c, 0x02, 0x27, 0xd0, 0xcc, 0x69, 0xde, 0x23 } };
    uint8_t   FNV1024bvalues[NTstrings][FNV1024size] = {
      { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x98, 0xd7, 0xc1, 0x9f, 0xbc, 0xe6, 0x53, 0xdf,
        0x22, 0x1b, 0x9f, 0x71, 0x7d, 0x34, 0x90, 0xff,
        0x95, 0xca, 0x87, 0xfd, 0xae, 0xf3, 0x0d, 0x1b,
        0x82, 0x33, 0x72, 0xf8, 0x5b, 0x24, 0xa3, 0x72,
        0xf5, 0x0e, 0x38, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x07, 0x68, 0x5c, 0xd8,
        0x1a, 0x49, 0x1d, 0xbc, 0xcc, 0x21, 0xad, 0x06,
        0x64, 0x8d, 0x09, 0xa5, 0xc8, 0xcf, 0x5a, 0x78,
        0x48, 0x20, 0x54, 0xe9, 0x14, 0x70, 0xb3, 0x3d,
        0xde, 0x77, 0x25, 0x2c, 0xae, 0xf6, 0x65, 0x97 },
      { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xf4,
        0x6e, 0xf4, 0x1c, 0xd2, 0x3a, 0x4d, 0xcd, 0xd4,
        0x06, 0x83, 0x49, 0x63, 0xb7, 0x8e, 0x82, 0x24,
        0x1a, 0x6f, 0x5c, 0xb0, 0x6f, 0x40, 0x3c, 0xbd,
        0x5a, 0x7c, 0x89, 0x03, 0xce, 0xf6, 0xa5, 0xf4,
        0xfd, 0xd2, 0x95, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x0b, 0x7c, 0xd7, 0xfb, 0x20,
        0xc3, 0x63, 0x1d, 0xc8, 0x90, 0x39, 0x52, 0xe9,
        0xee, 0xb7, 0xf6, 0x18, 0x69, 0x8f, 0x4c, 0x87,
        0xda, 0x23, 0xad, 0x74, 0xb2, 0xc5, 0xf6, 0xf1,
        0xfe, 0xc4, 0xa6, 0x4b, 0x54, 0x66, 0x18, 0xa2 },
      { 0x00, 0x09, 0xdc, 0x92, 0x10, 0x75, 0xfd, 0x8a,
        0x5e, 0x3e, 0x1a, 0x37, 0x2c, 0x72, 0xa5, 0x9b,
        0xb1, 0x0c, 0xca, 0x1a, 0x94, 0xc8, 0xb2, 0x38,
        0x7d, 0x63, 0xa7, 0xef, 0xa7, 0xfc, 0xa7, 0xa7,
        0x17, 0xa6, 0x4e, 0x6c, 0x2d, 0x62, 0xfb, 0x61,
        0x78, 0xf7, 0x86, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x67, 0x08,
        0xf4, 0x4d, 0x00, 0x8a, 0xaa, 0xb0, 0x86, 0x57,
        0x49, 0x35, 0x50, 0x2c, 0x49, 0x08, 0x7c, 0x84,
        0x9b, 0xcb, 0xbe, 0xfa, 0x03, 0x3f, 0x45, 0x2a,
        0xf6, 0x38, 0x24, 0x26, 0xba, 0x5d, 0x3b, 0xb5,
        0x71, 0xb6, 0x46, 0x5b, 0x2a, 0xe8, 0xc8, 0xf0 },
      { 0xc8, 0x01, 0xf8, 0xe0, 0x8a, 0xe9, 0x1b, 0x18,
        0x0b, 0x98, 0xdd, 0x7d, 0x9f, 0x65, 0xce, 0xb6,
        0x87, 0xca, 0x86, 0x35, 0x8c, 0x69, 0x05, 0xf6,
        0x0a, 0x7d, 0x10, 0x14, 0xc1, 0x82, 0xb0, 0x4f,
        0xd6, 0x08, 0xa2, 0xca, 0x4d, 0xd6, 0x0a, 0x30,
        0x0a, 0x15, 0x68, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x01, 0x80, 0x45, 0x14, 0x9a, 0xde,
        0x1c, 0x79, 0xab, 0xe3, 0xb7, 0x09, 0xa4, 0x06,
        0xf7, 0xd9, 0x20, 0x51, 0x69, 0xbe, 0xc5, 0x9b,
        0x12, 0x61, 0x40, 0xbc, 0xb9, 0x6f, 0x9d, 0x5d,
        0x3e, 0x2e, 0xa9, 0x1e, 0x21, 0xcd, 0xc2, 0x04,
        0x9f, 0x57, 0xbe, 0xcd, 0x00, 0x2d, 0x7c, 0x47 } };

    funcName = "FNV-1024";
    selected = FNV1024selected;
    /* test error checks */
    Terr = 0;
    TestR ( "init1", fnvSuccess, FNV1024init (&e1024Context) );
    CommonTest();
    TestR ( "init2", fnvNull,
            FNV1024init ( (FNV1024context *)0 ) );
    TestR ( "initBasis1", fnvNull,
            FNV1024initBasis ( (FNV1024context *)0, hash ) );
    TestR ( "blockin1", fnvNull,
            FNV1024blockin ( (FNV1024context *)0,
                           errtestbytes, NTestBytes ) );
    TestR ( "blockin2", fnvNull,
            FNV1024blockin ( &e1024Context, (uint8_t *)0,
                           NTestBytes ) );
    TestR ( "blockin3", fnvBadParam,
            FNV1024blockin ( &e1024Context, errtestbytes, -1 ) );
    e1024Context.Computed = FNVclobber+FNV1024state;
    TestR ( "blockin4", fnvStateError,
            FNV1024blockin ( &e1024Context, errtestbytes,
                           NTestBytes ) );
    TestR ( "stringin1", fnvNull,
            FNV1024stringin ( (FNV1024context *)0, errteststring ) );
    TestR ( "stringin2", fnvNull,
            FNV1024stringin ( &e1024Context, (char *)0 ) );
    TestR ( "stringin3", fnvStateError,
            FNV1024stringin ( &e1024Context, errteststring ) );
    TestR ( "result1", fnvNull,
            FNV1024result ( (FNV1024context *)0, hash ) );
    TestR ( "result2", fnvNull,
            FNV1024result ( &e1024Context, (uint8_t *)0  ) );
    TestR ( "result3", fnvStateError,
            FNV1024result ( &e1024Context, hash  ) );
    ErrTestReport ();
/* test actual results */
    Terr = 0;
    for ( i = 0; i < NTstrings; ++i ) {
        err = TestR ( "stringa", fnvSuccess,
                      FNV1024string ( teststring[i], hash ) );
        if ( err == fnvSuccess )
            TestNValue ( "stringb", teststring[i], FNV1024size,
                             hash,
                     FNV1024svalues[i] );
        err = TestR ( "blocka", fnvSuccess,
                      FNV1024block ( (uint8_t *)teststring[i],
                          (unsigned long)(strlen(teststring[i])+1),
                          hash ) );
        if ( err == fnvSuccess )
            TestNValue ( "blockb", teststring[i], FNV1024size,
                     hash,
                     FNV1024bvalues[i] );
/* now try testing the incremental stuff */
        err = TestR ( "inita", fnvSuccess,
                      FNV1024init ( &e1024Context ) );
        if ( err ) break;
        iLen = strlen ( teststring[i] );
        err = TestR ( "blockina", fnvSuccess,
                      FNV1024blockin ( &e1024Context,
                      (uint8_t *)teststring[i],
                      iLen/2 ) );
        if ( err ) break;
        err = TestR ( "stringina", fnvSuccess,
                      FNV1024stringin ( &e1024Context,
                      teststring[i] + iLen/2 ) );
        if ( err ) break;
        err = TestR ( "resulta", fnvSuccess,
                      FNV1024result ( &e1024Context, hash ) );
        if ( err == fnvSuccess )
            TestNValue ( "incrementala", teststring[i], FNV1024size,
                     hash,
                     (uint8_t *)&FNV1024svalues[i] );

/* now try testing file hash */
        err = TestR ( "fileafh", fnvSuccess,
                      FNV1024file (
                                 WriteTemp(teststring[i], iLen),
                                 hash )
                      );
        if ( err ) break;
        TestNValue ( "filebfh", teststring[i], FNV1024size,
                     hash,
                     (uint8_t *)&FNV1024svalues[i] );

    }
    ValueTestReport ();
}    /* end Test1024 */

<CODE ENDS>

6.4. Makefile

Below is a simple makefile to produce and run the test program or to provide a library with all the FNV functions supplied in it.

WARNING: When actually using the following as a makefile, the five character sequence "<TAB>" must be changed to a tab (0x09) character!

<CODE BEGINS> file "makefile"

# Makefile for fnv
# If you extract this file from RFC NNNN, the five character sequence
#     <TAB> below must be replace with a tab (0x09) character.

explanation:
<TAB>@echo Choose one of the following make targets:
<TAB>@echo make FNVhash -- test program
<TAB>@echo make libfnv.a -- library you can use
<TAB>@echo make clean -- removes all of the built targets

SRC=FNV1024.c FNV128.c FNV256.c FNV32.c FNV512.c FNV64.c
HDR=FNV32.h FNV64.h FNV128.h FNV256.h FNV512.h FNV1024.h \
<TAB>FNVErrorCodes.h FNVconfig.h fnv-private.h
OBJ=$(SRC:.c=.o)
CFLAGS=-Wall
AR=ar
ARFLAGS= rcs

FNVhash: libfnv.a main.c
<TAB>$(CC) $(CFLAGS) -o FNVhash main.c libfnv.a

libfnv.a: $(SRC) $(HDR)
<TAB>rm -f libfnv.a *.o
<TAB>$(CC) $(CFLAGS) -c $(SRC)
<TAB>$(AR) $(ARFLAGS) libfnv.a $(OBJ)

clean:
<TAB>rm -rf libfnv.a FNVhash *.o

<CODE ENDS>

7. Security Considerations

This document is intended to provide convenient open source-access by the Internet community to the FNV non-cryptographic hash. No assertion of suitability for cryptographic applications is made for the FNV hash algorithms.

7.1. Why is FNV Non-Cryptographic?

A full discussion of cryptographic hash requirements and strength is beyond the scope of this document. However, here are three characteristics of FNV that would generally be considered to make it non-cryptographic:

  1. Sticky State - A cryptographic hash should not have a state in which it can stick for a plausible input pattern. But, in the very unlikely event that the FNV hash variable becomes zero and the input is a sequence of zeros, the hash variable will remain at zero until there is a non-zero input byte and the final hash value will be unaffected by the length of that sequence of zero input bytes. Of course, for the common case of fixed length input, this would usually not be significant because the number of non-zero bytes would vary inversely with the number of zero bytes and for some types of input, runs of zeros do not occur. Furthermore, the use of a different offset_basis or the inclusion of even a little unpredictable input may be sufficient to stop an adversary from inducing a zero hash variable.
  2. Diffusion - Every output bit of a cryptographic hash should be an equally complex function of every input bit. But it is easy to see that the least significant bit of a direct FNV hash is the XOR of the least significant bits of every input byte and does not depend on any other input bits. While more complex, the second through seventh least significant bits of an FNV hash have a similar weakness; only the top bit of the bottom byte of output, and higher order bits, depend on all input bits. If these properties are considered a problem, they can be easily fixed by XOR folding (see Section 3).
  3. Work Factor - Depending on intended use, it is frequently desirable that a hash function should be computationally expensive for general purpose and graphics processors since these may be profusely available through elastic cloud services or botnets. This is to slow down testing of possible inputs if the output is known. But FNV is designed to be inexpensive on a general-purpose processor. (See Appendix A.)

Nevertheless, none of the above have proven to be a problem in actual practice for the many non-cryptographic applications of FNV.

7.2. Inducing Collisions

While use of a cryptographic hash should be considered when active adversaries are a factor, the following attack can be made much more difficult with very minor changes in the use of FNV:

If FNV is being used in a known way for hash tables in a network server or the like, for example some part of a web server, an adversary could send requests calculated to cause hash table collisions and induce substantial processing delays. As mentioned in Section 2.2, use of an offset_basis not known by the adversary will substantially reduce or eliminate this problem.

8. IANA Considerations

This document requires no IANA Actions.

9. Normative References

[RFC0020]
Cerf, V., "ASCII format for network interchange", STD 80, RFC 20, DOI 10.17487/RFC0020, , <https://www.rfc-editor.org/info/rfc20>.

10. Informative References

[BFDseq]
Jethanandani, M., Agarwal, S., Mishra, A., Saxena, A., and A. DeKok, "Secure BFD Sequence Numbers", , <draft-ietf-bfd-secure-sequence-numbers-09.txt>.
[FNV]
Fowler-Noll-Vo, "FNV website", <http://www.isthe.com/chongo/tech/comp/fnv/index.html>.
[IEEE]
Institute for Electrical and Electronics Engineers, "IEEE website", <http:www.ieee.org>.
[IEEE8021Qbp]
"Media Access Control (MAC) Bridges and Virtual Bridged Local Area Networks - Equal Cost Multiple Path (ECMP)", IEEE Std 802.1Qbp-2014, .
[IPv6flow]
Anderson, L., Brownlee, N., and B. Carpenter, "Comparing Hash Function Algorithms for the IPv6 Flow Label", University of Auckland Department of Computer Science Technical Report 2012-002, ISSN 1173-3500, , <https://researchspace.auckland.ac.nz/bitstream/handle/2292/13240/flowhashRep.pdf>.
[RFC3174]
Eastlake 3rd, D. and P. Jones, "US Secure Hash Algorithm 1 (SHA1)", RFC 3174, DOI 10.17487/RFC3174, , <https://www.rfc-editor.org/info/rfc3174>.
[RFC6194]
Polk, T., Chen, L., Turner, S., and P. Hoffman, "Security Considerations for the SHA-0 and SHA-1 Message-Digest Algorithms", RFC 6194, DOI 10.17487/RFC6194, , <https://www.rfc-editor.org/info/rfc6194>.
[RFC6234]
Eastlake 3rd, D. and T. Hansen, "US Secure Hash Algorithms (SHA and SHA-based HMAC and HKDF)", RFC 6234, DOI 10.17487/RFC6234, , <https://www.rfc-editor.org/info/rfc6234>.
[RFC6437]
Amante, S., Carpenter, B., Jiang, S., and J. Rajahalme, "IPv6 Flow Label Specification", RFC 6437, DOI 10.17487/RFC6437, , <https://www.rfc-editor.org/info/rfc6437>.
[RFC7357]
Zhai, H., Hu, F., Perlman, R., Eastlake 3rd, D., and O. Stokes, "Transparent Interconnection of Lots of Links (TRILL): End Station Address Distribution Information (ESADI) Protocol", RFC 7357, DOI 10.17487/RFC7357, , <https://www.rfc-editor.org/info/rfc7357>.
[RFC7873]
Eastlake 3rd, D. and M. Andrews, "Domain Name System (DNS) Cookies", RFC 7873, DOI 10.17487/RFC7873, , <https://www.rfc-editor.org/info/rfc7873>.
[RFC8200]
Deering, S. and R. Hinden, "Internet Protocol, Version 6 (IPv6) Specification", STD 86, RFC 8200, DOI 10.17487/RFC8200, , <https://www.rfc-editor.org/info/rfc8200>.

Appendix A. Work Comparison with SHA-1

This section provides a simplistic rough comparison of the level of effort required per input byte to compute FNV-1a and SHA-1 [RFC3174].

Ignoring transfer of control and conditional tests and equating all logical and arithmetic operations, FNV requires 2 operations per byte, an XOR and a multiply.

SHA-1 is a relatively weak cryptographic hash producing a 160-bit hash. It has been partially broken [RFC6194]. It is actually designed to accept a bit vector input although almost all computer uses apply it to an integer number of bytes. It processes blocks of 512 bits (64 bytes) and we estimate the effort involved in SHA-1 processing a full block. Ignoring SHA-1 initial set up, transfer of control, and conditional tests, but counting all logical and arithmetic operations, including counting indexing as an addition, SHA-1 requires 1,744 operations per 64 bytes block or 27.25 operations per byte. So, by this rough measure, it is a little over 13 times the effort of FNV for large amounts of data. However, FNV is commonly used for small inputs. Using the above comparison method, for inputs of N bytes, where N is <= 55 so SHA-1 will take one block (SHA-1 includes padding and an 8-byte length at the end of the data in the last block), the ratio of the effort for SHA-1 to the effort for FNV will be 872/N. For example, with a 4-byte input such as an IPv4 address, SHA-1 will take 218 times as much effort as FNV, and wih a 6-byte input such as a MAC address, SHA-1 will take a little over 145 times as much effort as FNV.

Stronger cryptographic functions than SHA-1 generally have an even higher work factor.

Appendix B. Previous IETF FNV Code

FNV-1a was referenced in draft-ietf-tls-cached-info-08.txt that has since expired. Below is the Java code for FNV64 from that TLS draft included with the kind permission of the author:

<CODE BEGINS>
 /*
 * Java code sample, implementing 64 bit FNV-1a
 * By Stefan Santesson
 */

import java.math.BigInteger;

public class FNV {

   static public BigInteger getFNV1aToByte(byte[] inp) {

       BigInteger m = new BigInteger("2").pow(64);
       BigInteger fnvPrime = new BigInteger("1099511628211");
       BigInteger fnvOffsetBasis =
               new BigInteger("14695981039346656037");

       BigInteger digest = fnvOffsetBasis;

       for (byte b : inp) {
           digest = digest.xor(BigInteger.valueOf((int) b & 255));
           digest = digest.multiply(fnvPrime).mod(m);
       }
       return digest;

   }
}

<CODE ENDS>

Appendix C. Change History

RFC Editor Note: Please delete this appendix on publication.

C.1. From -00 to -01

  1. Add Security Considerations section on why FNV is non-cryptographic.
  2. Add Appendix A on a work factor comparison with SHA-1.
  3. Add Appendix B concerning previous IETF draft referenced to FNV.
  4. Minor editorial changes.

C.2. From -01 to -02

  1. Correct FNV_Prime determination criteria and add note as to why s < 5 and s > 10 are not considered.
  2. Add acknowledgements list.
  3. Add a couple of references.
  4. Minor editorial changes.

C.3. From -02 to -05

  1. Minor addition to Section 6, point 3.
  2. Add Twitter as a use example and IPv6 flow hash study reference.
  3. Minor editorial changes.

C.4. From -05 to -08

  1. Add code subsections.
  2. Update Author info.
  3. Minor edits.

C.5. From -08 to -09

  1. Change reference for ASCII to [RFC0020].
  2. Add more details on history of the string used to compute offset_basis.
  3. Re-write "Work Factor" part of Section 6 to be more precise.
  4. Minor editorial changes.

C.6. From -09 to -10

  1. Inclusion of initial partial version of code and some documentation about the code, Section 6.
  2. Insertion of new Section 4 on hashing values.

C.7. From -10 to -12

Changes based on code improvements primarily from Tony Hansen who has been added as an author. Changes based on comments from Mukund Sivaraman and Roman Donchenko.

C.8. From -12 to -13

Fixed bug in pseudocode in Section 2.3.

Change code to eliminate the BigEndian flag and so there are separate byte vector output routines for FNV32 and FNV64, equivalent to the other routines, and integer output routines for cases where Endianness consistency is not required.

C.9. From -13 to -17

  1. Update an author address
  2. Update an author affiliation.

C.10. From -17 to -19

  1. Add reference to draft-ietf-bfd-secure-sequence-numbers.
  2. Add references to the following, each of which uses FNV: RFC 7357, RFC 7873, and IEEE Std. 802.1Qbp-2014
  3. Update author information
  4. Minor editorial changes.

C.11. From -19 to -20

Convert to XML v3. Fix code for longer FNV hashes.

C.12. From -20 to -21

Update Twitter to X. Minor Editorial changes.

C.13. From -21 to -22

Update Landon's email. Minor Editorial changes. Update to substantially improved code.

C.14. From -22 to -23

  1. Author info update.
  2. Make byte vector returning versions of functions available for all sizes.
  3. Remove big endian code due to difficulty in finding someone to test it. This only affects multi-byte integer returns and correct results can always be obtained by using the byte vector return versions of functions.

C.15. From -23 to -25

  1. Correct some errors in comments in the code, fix some omissions and add testing for the file hashing code, and other code polishing
  2. Minor editorial changes.

C.16. From -25 to -28

  1. Add autodetect in FNVconfig.h of target support for 64-bit integers.
  2. Add discussion of what source files are needed for particular uses.
  3. Fix code so it compiles properly if all .c files are concatenated as well as when they are compiled separately.
  4. Add makefile section.
  5. Fix some problems with &gt; and >.
  6. Minor editorial improvements.

C.17. From -28 to -29

Responding to IETF Last Call Comments: minor re-organization of Introduction and addition to the Introduction of a some non-applicability considerations. Minor editorial improvements.

Acknowledgements

The contributions of the following, listed is alphabetic order, are gratefully acknowledged:

Roman Donchenko, Frank Ellermann, Tony Finch, Eliot Lear, Bob Moskowitz, Gayle Noble, Stefan Santesson, Mukund Sivaraman, Paul Hoffman, and Paul Wouters.

Authors' Addresses

Glenn S. Fowler
Google
Landon Curt Noll
Cisco Systems
170 West Tasman Drive
San Jose, California 95134
United States of America
Phone: +1-408-424-1102
URI: http://www.isthe.com/chongo/index.html
Kiem-Phong Vo
Google
Donald E. Eastlake 3rd
Independent
2386 Panoramic Circle
Apopka, Florida 32703
United States of America
Phone: +1-508-333-2270
Tony Hansen
AT&T
200 Laurel Avenue South
Middletown, New Jersey 07748
United States of America