ut0guarded.h

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/** @file include/ut0guarded.h
The ut::Guarded template which protects access to another class with mutex. */
 
#ifndef ut0guarded_h
#define ut0guarded_h
 
#ifndef UNIV_LIBRARY
#include "ut0cpu_cache.h"
#include "ut0mutex.h"
#endif
 
namespace ut {
// TBD: should latch_id be specified at runtime?
template <typename Inner, latch_id_t latch_id>
class Guarded {
#ifndef UNIV_LIBRARY
  Cacheline_padded<IB_mutex> mutex{latch_id};
#endif
  Inner inner;
 
 public:
  template <typename F>
  auto latch_and_execute(F &&f, const ut::Location &loc) {
#ifndef UNIV_LIBRARY
    IB_mutex_guard guard{&mutex, loc};
#endif
    return std::forward<F>(f)(inner);
  }
 
  const Inner &peek() const { return inner; }
};
}  // namespace ut
#endif /* ut0guarded_h */