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Diffstat (limited to '')
-rw-r--r-- | src/include/blobhash.h | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/src/include/blobhash.h b/src/include/blobhash.h new file mode 100644 index 00000000..597884e4 --- /dev/null +++ b/src/include/blobhash.h @@ -0,0 +1,47 @@ +// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*- +/* + * Ceph - scalable distributed file system + * + * Copyright (C) 2004-2006 Sage Weil <sage@newdream.net> + * + * This is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License version 2.1, as published by the Free Software + * Foundation. See file COPYING. + * + */ + +#ifndef CEPH_BLOBHASH_H +#define CEPH_BLOBHASH_H + +#include "hash.h" + +/* +- this is to make some of the STL types work with 64 bit values, string hash keys, etc. +- added when i was using an old STL.. maybe try taking these out and see if things + compile now? +*/ + +class blobhash { +public: + uint32_t operator()(const char *p, unsigned len) { + static rjhash<uint32_t> H; + uint32_t acc = 0; + while (len >= sizeof(acc)) { + acc ^= *(uint32_t*)p; + p += sizeof(uint32_t); + len -= sizeof(uint32_t); + } + int sh = 0; + while (len) { + acc ^= (uint32_t)*p << sh; + sh += 8; + len--; + p++; + } + return H(acc); + } +}; + + +#endif |