src/mem/shared_memory_server.hh

/*
 * Copyright 2022 Google, Inc.
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 * modification, are permitted provided that the following conditions are
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 * neither the name of the copyright holders nor the names of its
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 * this software without specific prior written permission.
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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#ifndef __MEM_SHARED_MEMORY_SERVER_HH__
#define __MEM_SHARED_MEMORY_SERVER_HH__

#include <memory>
#include <string>

#include "base/pollevent.hh"
#include "params/SharedMemoryServer.hh"
#include "sim/sim_object.hh"
#include "sim/system.hh"

namespace gem5
{
namespace memory
{

class SharedMemoryServer : public SimObject
{
  public:
    enum class RequestType : int
    {
        kGetPhysRange = 0,
    };

    explicit SharedMemoryServer(const SharedMemoryServerParams& params);
    ~SharedMemoryServer();

  private:
    class BaseShmPollEvent : public PollEvent
    {
      public:
        BaseShmPollEvent(int fd, SharedMemoryServer* shm_server);

        const std::string& name() const;

      protected:
        bool tryReadAll(void* buffer, size_t size);

        SharedMemoryServer* shmServer;
        std::string eventName;
    };

    class ListenSocketEvent : public BaseShmPollEvent
    {
      public:
        using BaseShmPollEvent::BaseShmPollEvent;
        void process(int revent) override;
    };

    class ClientSocketEvent : public BaseShmPollEvent
    {
      public:
        using BaseShmPollEvent::BaseShmPollEvent;
        void process(int revent) override;
    };

    std::string unixSocketPath;
    System* system;

    int serverFd;
    std::unique_ptr<ListenSocketEvent> listenSocketEvent;
    std::unique_ptr<ClientSocketEvent> clientSocketEvent;
};

} // namespace memory
} // namespace gem5

#endif  // __MEM_SHARED_MEMORY_SERVER_HH__