Hasher.H
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23 
24 InNamespace
25  Foam
26 
27 Description
28  Misc. hashing functions, mostly from Bob Jenkins.
29 
30  The Jenkins hashing function(s) is similar in speed to Paul Hsieh's
31  SuperFast hash, but is public domain, supports incremental hashing
32  and has been reported to have better characteristics.
33  It is also what postgresql seems to be using.
34 
35 SeeAlso
36  http://burtleburtle.net/bob/c/lookup3.c
37  and HasherInt.H for a specialized version
38 
39 SourceFiles
40  Hasher.C
41 
42 \*---------------------------------------------------------------------------*/
43 
44 #ifndef Hasher_H
45 #define Hasher_H
46 
47 #include <cstddef>
48 
49 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
50 
51 namespace Foam
52 {
53 
54 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
55 
56  //- Bob Jenkins's 96-bit mixer hashing function (lookup3)
57  // \param[in] data - a character stream
58  // \param[in] len - the number of bytes
59  // \param[in] seed - the previous hash, or an arbitrary value
60  unsigned Hasher(const void* data, size_t len, unsigned seed = 0);
61 
62 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
63 
64 } // End namespace Foam
65 
66 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
67 
68 #endif
69 
70 // ************************************************************************* //
unsigned Hasher(const void *data, size_t len, unsigned seed=0)
Bob Jenkins&#39;s 96-bit mixer hashing function (lookup3)
Definition: Hasher.C:476
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