status.hpp

#ifndef FENIX_MPIXX_STATUS_HPP
#define FENIX_MPIXX_STATUS_HPP
 
#include <mpi.h>
#include <tuple>
 
namespace fenix::mpixx {
class Status {
 public:
  int return_value = MPI_SUCCESS;
  MPI_Status status;
 
  Status() = default;
  Status(int r) : return_value(r) {}
  auto operator=(int r) {
    return_value = r;
    return *this;
  }
 
  operator bool() const { return return_value == MPI_SUCCESS; }
 
  operator int() const { return return_value; }
  bool operator==(int r) const { return return_value == r; }
 
  operator MPI_Status() const { return status; }
  operator MPI_Status*() { return &status; }
 
  // to support structured unbinding
  template <size_t I>
  auto&& get() && {
    if constexpr (I == 0) return std::move(return_value);
    if constexpr (I == 1) return std::move(status);
  }
};
} // namespace fenix::mpixx
 
// Supporting structured unbinding for Status
namespace std {
template <>
struct tuple_size<fenix::mpixx::Status> : std::integral_constant<size_t, 2> {};
 
template <>
struct tuple_element<0, fenix::mpixx::Status> {
  using type = int;
};
template <>
struct tuple_element<1, fenix::mpixx::Status> {
  using type = MPI_Status;
};
} // namespace std
 
#endif // FENIX_MPIXX_STATUS_HPP