forked from boostorg/unordered
6f45d36d97
Remove deprecated headers, move hash_fwd.hpp into hash subdirectory. And several minor internal changes. Mostly minor internal details. Merged revisions 51262-51263,51407-51409,51504-51505,51644-51646,51667 via svnmerge from https://svn.boost.org/svn/boost/trunk ........ r51262 | danieljames | 2009-02-15 19:32:04 +0000 (Sun, 15 Feb 2009) | 1 line Use the new 'boost:' links for the hash, unordered and quickbook documentation. ........ r51263 | danieljames | 2009-02-15 19:32:19 +0000 (Sun, 15 Feb 2009) | 2 lines Don't copy images for the standalone hash and unordered documentation, was only really required before the libraries were integrated into boost. ........ r51407 | danieljames | 2009-02-22 23:49:51 +0000 (Sun, 22 Feb 2009) | 1 line Fix the hash dirname. ........ r51408 | danieljames | 2009-02-22 23:50:04 +0000 (Sun, 22 Feb 2009) | 1 line Make copy_buckets and move_buckets member functions - so that calling them is a bit simpler. ........ r51409 | danieljames | 2009-02-22 23:50:20 +0000 (Sun, 22 Feb 2009) | 1 line Move some of the data structure classes out of hash table data. ........ r51504 | danieljames | 2009-03-01 14:15:09 +0000 (Sun, 01 Mar 2009) | 1 line Add missing return for operator=. ........ r51505 | danieljames | 2009-03-01 14:15:39 +0000 (Sun, 01 Mar 2009) | 3 lines Make the sort stable. Doesn't really matter, but it might as well be. ........ r51644 | danieljames | 2009-03-08 09:44:51 +0000 (Sun, 08 Mar 2009) | 1 line Detab. ........ r51645 | danieljames | 2009-03-08 09:45:11 +0000 (Sun, 08 Mar 2009) | 4 lines Move hash_fwd into the hash subdirectory. I should have done this in the last release. But now all of the hash implementation is in the hash subdirectory. ........ r51646 | danieljames | 2009-03-08 09:45:30 +0000 (Sun, 08 Mar 2009) | 3 lines Remove deprecated headers. Fixes #2412. ........ r51667 | danieljames | 2009-03-09 20:56:23 +0000 (Mon, 09 Mar 2009) | 1 line Update copyright dates in hash and unordered. ........ [SVN r51729]
67 lines
2.0 KiB
C++
67 lines
2.0 KiB
C++
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// Copyright 2008-2009 Daniel James.
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// Distributed under the Boost Software License, Version 1.0. (See accompanying
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// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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// This code is also released into the public domain.
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// Algorithm from: http://www.isthe.com/chongo/tech/comp/fnv/
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#include <string>
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namespace hash
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{
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template <std::size_t FnvPrime, std::size_t OffsetBasis>
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struct basic_fnv_1
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{
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std::size_t operator()(std::string const& text) const
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{
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std::size_t hash = OffsetBasis;
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for(std::string::const_iterator it = text.begin(), end = text.end();
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it != end; ++it)
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{
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hash *= FnvPrime;
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hash ^= *it;
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}
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return hash;
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}
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};
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template <std::size_t FnvPrime, std::size_t OffsetBasis>
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struct basic_fnv_1a
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{
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std::size_t operator()(std::string const& text) const
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{
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std::size_t hash = OffsetBasis;
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for(std::string::const_iterator it = text.begin(), end = text.end();
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it != end; ++it)
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{
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hash ^= *it;
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hash *= FnvPrime;
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}
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return hash;
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}
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};
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// For 32 bit machines:
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const std::size_t fnv_prime = 16777619u;
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const std::size_t fnv_offset_basis = 2166136261u;
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// For 64 bit machines:
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// const std::size_t fnv_prime = 1099511628211u;
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// const std::size_t fnv_offset_basis = 14695981039346656037u;
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// For 128 bit machines:
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// const std::size_t fnv_prime = 309485009821345068724781401u;
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// const std::size_t fnv_offset_basis = 275519064689413815358837431229664493455u;
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// For 256 bit machines:
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// const std::size_t fnv_prime = 374144419156711147060143317175368453031918731002211u;
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// const std::size_t fnv_offset_basis = 100029257958052580907070968620625704837092796014241193945225284501741471925557u;
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typedef basic_fnv_1<fnv_prime, fnv_offset_basis> fnv_1;
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typedef basic_fnv_1a<fnv_prime, fnv_offset_basis> fnv_1a;
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}
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