reference_cache_common.h

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/* Copyright (c) 2020, 2024, Oracle and/or its affiliates.
 
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#ifndef REFERENCE_CACHE_COMMON_H
#define REFERENCE_CACHE_COMMON_H
 
#include <atomic>
#include <set>
#include <string>
 
namespace reference_caching {
 
extern PSI_memory_key KEY_mem_reference_cache;
#define PSI_category "refcache"
 
struct Service_name_entry {
  explicit Service_name_entry(const char *name, unsigned int count)
      : name_{name}, count_{count} {}
  Service_name_entry(const Service_name_entry &src)
      : Service_name_entry(src.name_.c_str(), src.count_.load()) {}
  Service_name_entry &operator=(const Service_name_entry &rhs) {
    name_ = rhs.name_;
    count_ = rhs.count_.load();
    return *this;
  }
  std::string name_;
  mutable std::atomic<unsigned int> count_{0};
};
 
struct Compare_service_name_entry {
  bool operator()(const Service_name_entry &lhs,
                  const Service_name_entry &rhs) const {
    return lhs.name_ < rhs.name_;
  }
};
 
template <class Key = Service_name_entry,
          class Less = Compare_service_name_entry>
class service_names_set
    : public std::set<Key, Less, Component_malloc_allocator<Key>> {
 public:
  service_names_set()
      : std::set<Key, Less, Component_malloc_allocator<Key>>(
            Component_malloc_allocator<>(KEY_mem_reference_cache)) {}
};
 
}  // namespace reference_caching
 
#endif /* REFERENCE_CACHE_COMMON_H */