rocksdb/util/stl_wrappers.h

52 lines
1.5 KiB
C
Raw Normal View History

// Copyright (c) 2013, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.
//
#pragma once
#include "util/murmurhash.h"
#include "util/coding.h"
#include "rocksdb/memtablerep.h"
#include "rocksdb/slice.h"
namespace rocksdb {
namespace stl_wrappers {
class Base {
protected:
const MemTableRep::KeyComparator& compare_;
explicit Base(const MemTableRep::KeyComparator& compare)
: compare_(compare) { }
};
struct Compare : private Base {
explicit Compare(const MemTableRep::KeyComparator& compare)
: Base(compare) { }
inline bool operator()(const char* a, const char* b) const {
return compare_(a, b) < 0;
}
};
struct Hash {
inline size_t operator()(const char* buf) const {
Slice internal_key = GetLengthPrefixedSlice(buf);
Slice value =
GetLengthPrefixedSlice(internal_key.data() + internal_key.size());
unsigned int hval = MurmurHash(internal_key.data(), internal_key.size(),
0);
hval = MurmurHash(value.data(), value.size(), hval);
return hval;
}
};
struct KeyEqual : private Base {
explicit KeyEqual(const MemTableRep::KeyComparator& compare)
: Base(compare) { }
inline bool operator()(const char* a, const char* b) const {
return this->compare_(a, b) == 0;
}
};
}
}