Hasher.H
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10License
11 This file is part of OpenFOAM.
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25
26InNamespace
27 Foam
28
29Description
30 Miscellaneous hashing functions, mostly from Bob Jenkins.
31
32 The Jenkins hashing function(s) is similar in speed to Paul Hsieh's
33 SuperFast hash, but is public domain, supports incremental hashing
34 and has been reported to have better characteristics.
35 It is also what postgresql seems to be using.
36
37See also
38 http://burtleburtle.net/bob/c/lookup3.c
39 and HasherInt.H for a specialized version
40
41SourceFiles
42 Hasher.C
43
44\*---------------------------------------------------------------------------*/
45
46#ifndef Hasher_H
47#define Hasher_H
48
49#include <cstddef>
50
51// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
52
53namespace Foam
54{
55
56// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
57
58//- Bob Jenkins's 96-bit mixer hashing function (lookup3)
59// \param[in] data - a character stream
60// \param[in] len - the number of bytes
61// \param[in] seed - the previous hash, or an arbitrary value
62unsigned Hasher(const void* data, size_t len, unsigned seed = 0);
63
64// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
65
66} // End namespace Foam
67
68// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
69
70#endif
71
72// ************************************************************************* //
Namespace for OpenFOAM.
unsigned Hasher(const void *data, size_t len, unsigned seed=0)
Bob Jenkins's 96-bit mixer hashing function (lookup3)
Definition: Hasher.C:581