45 lines
870 B
C++
45 lines
870 B
C++
#ifndef MEMGRAPH_MVCC_VERSION_HPP
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#define MEMGRAPH_MVCC_VERSION_HPP
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#include <atomic>
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namespace mvcc
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{
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template <class T>
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class Version
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{
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public:
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Version() : versions(nullptr) {}
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~Version()
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{
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delete versions.load();
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}
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Version(T* value) : versions(value) {}
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// return a pointer to a newer version stored in this record
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T* newer()
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{
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return versions.load();
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}
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// set a newer version of this record
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void newer(T* value)
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{
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versions.store(value);
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}
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private:
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// this is an atomic singly-linked list of all versions. this pointer
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// points to a newer version of this record. the newer version also has
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// this pointer which points to an even more recent version. if no newer
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// version is present, this value points to a nullptr
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std::atomic<T*> newer_version;
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};
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}
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#endif
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