rocksdb/util/slice.cc

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// Copyright (c) 2012 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file. See the AUTHORS file for names of contributors.
#include "rocksdb/slice_transform.h"
#include "rocksdb/slice.h"
namespace rocksdb {
namespace {
class FixedPrefixTransform : public SliceTransform {
private:
size_t prefix_len_;
public:
explicit FixedPrefixTransform(size_t prefix_len) : prefix_len_(prefix_len) { }
virtual const char* Name() const {
return "rocksdb.FixedPrefix";
}
virtual Slice Transform(const Slice& src) const {
assert(InDomain(src));
return Slice(src.data(), prefix_len_);
}
virtual bool InDomain(const Slice& src) const {
return (src.size() >= prefix_len_);
}
virtual bool InRange(const Slice& dst) const {
return (dst.size() == prefix_len_);
}
};
class NoopTransform : public SliceTransform {
public:
explicit NoopTransform() { }
virtual const char* Name() const {
return "rocksdb.Noop";
}
virtual Slice Transform(const Slice& src) const {
return src;
}
virtual bool InDomain(const Slice& src) const {
return true;
}
virtual bool InRange(const Slice& dst) const {
return true;
}
};
}
const SliceTransform* NewFixedPrefixTransform(size_t prefix_len) {
return new FixedPrefixTransform(prefix_len);
}
const SliceTransform* NewNoopTransform() {
return new NoopTransform;
}
} // namespace rocksdb