mirror of https://gitee.com/bigwinds/arangodb
68 lines
2.2 KiB
C++
68 lines
2.2 KiB
C++
////////////////////////////////////////////////////////////////////////////////
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/// DISCLAIMER
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///
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/// Copyright 2014-2016 ArangoDB GmbH, Cologne, Germany
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/// Copyright 2004-2014 triAGENS GmbH, Cologne, Germany
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///
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/// Licensed under the Apache License, Version 2.0 (the "License");
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/// you may not use this file except in compliance with the License.
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/// You may obtain a copy of the License at
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///
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/// http://www.apache.org/licenses/LICENSE-2.0
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///
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/// Unless required by applicable law or agreed to in writing, software
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/// distributed under the License is distributed on an "AS IS" BASIS,
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/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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/// See the License for the specific language governing permissions and
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/// limitations under the License.
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///
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/// Copyright holder is ArangoDB GmbH, Cologne, Germany
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///
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/// @author Jan Steemann
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////////////////////////////////////////////////////////////////////////////////
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#ifndef ARANGOD_READ_CACHE_REVISION_READER_H
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#define ARANGOD_READ_CACHE_REVISION_READER_H 1
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#include "Basics/Common.h"
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#include "ReadCache/RevisionTypes.h"
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#include <velocypack/Slice.h>
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namespace arangodb {
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class GlobalRevisionCacheChunk;
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// guard that ensures a revision can be read from the global revision cache
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// the dtor will automatically free any acquired resources
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class RevisionReader {
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public:
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RevisionReader();
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RevisionReader(GlobalRevisionCacheChunk* chunk, RevisionOffset offset, RevisionVersion version);
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~RevisionReader();
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RevisionReader(RevisionReader const&) = delete;
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RevisionReader& operator=(RevisionReader const&) = delete;
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RevisionReader(RevisionReader&&) noexcept;
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RevisionReader& operator=(RevisionReader&&) noexcept;
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arangodb::velocypack::Slice revision() const;
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uint64_t collectionId() const;
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GlobalRevisionCacheChunk* chunk() const { return _chunk; }
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RevisionOffset offset() const { return _offset; }
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RevisionVersion version() const { return _version; }
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void stealReference() { _ownsReference = false; }
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private:
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GlobalRevisionCacheChunk* _chunk;
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RevisionOffset _offset;
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RevisionVersion _version;
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bool _ownsReference;
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bool _ownsReader;
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};
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}
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#endif
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