1 /* Copyright 2017-2021 PaGMO development team 2 3 This file is part of the PaGMO library. 4 5 The PaGMO library is free software; you can redistribute it and/or modify 6 it under the terms of either: 7 8 * the GNU Lesser General Public License as published by the Free 9 Software Foundation; either version 3 of the License, or (at your 10 option) any later version. 11 12 or 13 14 * the GNU General Public License as published by the Free Software 15 Foundation; either version 3 of the License, or (at your option) any 16 later version. 17 18 or both in parallel, as here. 19 20 The PaGMO library is distributed in the hope that it will be useful, but 21 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 22 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 23 for more details. 24 25 You should have received copies of the GNU General Public License and the 26 GNU Lesser General Public License along with the PaGMO library. If not, 27 see https://www.gnu.org/licenses/. */ 28 29 #ifndef PAGMO_ISLANDS_FORK_ISLAND_HPP 30 #define PAGMO_ISLANDS_FORK_ISLAND_HPP 31 32 #include <pagmo/config.hpp> 33 34 #if defined(PAGMO_WITH_FORK_ISLAND) 35 36 #include <atomic> 37 #include <string> 38 39 #include <unistd.h> 40 41 #include <pagmo/detail/visibility.hpp> 42 #include <pagmo/island.hpp> 43 #include <pagmo/s11n.hpp> 44 45 namespace pagmo 46 { 47 48 // Fork island: will offload the evolution to a child process created with the fork() system call. 49 class PAGMO_DLL_PUBLIC fork_island 50 { 51 public: 52 // NOTE: we need to implement these because of the m_pid member, 53 // which has a trivial def ctor and which is missing the copy/move ctors. 54 // m_pid is only informational and it is relevant only while the evolution 55 // is undergoing, we will not copy it or serialize it. fork_island()56 fork_island() : m_pid(0) {} fork_island(const fork_island &)57 fork_island(const fork_island &) : fork_island() {} fork_island(fork_island &&)58 fork_island(fork_island &&) : fork_island() {} 59 void run_evolve(island &) const; get_name() const60 std::string get_name() const 61 { 62 return "Fork island"; 63 } 64 std::string get_extra_info() const; 65 // Get the PID of the child. get_child_pid() const66 pid_t get_child_pid() const 67 { 68 return m_pid.load(); 69 } 70 71 private: 72 // Object serialization 73 friend class boost::serialization::access; 74 template <typename Archive> 75 void serialize(Archive &, unsigned); 76 77 mutable std::atomic<pid_t> m_pid; 78 }; 79 80 } // namespace pagmo 81 82 PAGMO_S11N_ISLAND_EXPORT_KEY(pagmo::fork_island) 83 84 #else 85 86 #error The fork_island.hpp header was included, but the fork island is not available on the current platform 87 88 #endif 89 90 #endif 91